{"Bibliographic":{"Title":"Environmental Research Laboratories Programs and Plans","Authors":"","Publication date":"1984","Publisher":""},"Administrative":{"Date created":"08-20-2023","Language":"English","Rights":"CC 0","Size":"0000706385"},"Pages":["ENVIRONMENTAL\n7.5\n8\nRESEARCH\n34/\n3\nLABORATORIES\nPROGRAMS\nAND\nPLANS\n1985\nFY1984\nPROGRAMS\nAND\nFY 1985\nLIBRARY\nPLANS\nMAR 2 0 1985\nN.O.A.A.\nU.S. Dept. of Commerce\nATMOSPHERIC\nAND\nact\nNOAA\nAMOUNT\nusal\nCOMMUNITY\nMENT\nOF\nU.S. Department of Commerce\nNational Oceanic and Atmospheric Administration\nEnvironmental Research Laboratories","ENVIRONMENTAL\nQC\nRESEARCH\n8075\nE58\nLABORATORIES\n1984\nPROGRAMS\n1985\nAND\nPLANS\nFY 1984\nPROGRAMS\nAND\nFY 1985\nPLANS\nDECEMBER 1984\nDEPARTMENT COMMUNITY\nOF\n*\nWITH\nSTATES\nOF\nU.S. Department of Commerce\nNational Oceanic and Atmospheric Administration\nEnvironmental Research Laboratories\nBoulder, Colorado\nVernon E. Derr, Director","NOTICE\nMention of a commercial company or product does not constitute\nan endorsement by NOAA Environmental Research Laboratories.\nUse for publicity or advertising purposes of information from\nthis publication concerning proprietary products or the tests\nof such products is not authorized.\nDocument available in Office of Programs, ERL, Boulder, Colorado.","Environmental Research Laboratories\nDirector\nO/P\nDep. Director\nESG\nCooperative\nCRP\nWRP\nPROFS\nWMP\nInstitutes\nAOML\nPMEL\nGLERL\nGFDL\nNSSL\nWPL\nARL\nAL\nSEL\nThe mission of the Environmental Research Laboratories (ERL) is to conduct an integrated\nprogram of fundamental research, related technology development, and services to im-\nprove understanding and prediction of the geophysical environment comprising the oceans\nand inland waters, the lower and upper atmosphere, the space environment, and the Earth.\nCONTENTS\nIntroduction and Summary of ERL Research\n1\nOffice of the Director\n17\nOD\nEnvironmental Sciences Group\n19\nESG\nClimate Research Program\n19\nCRP\nWeather Research Program\n26\nWRP\nProgram for Regional Observing and Forecasting Services\n31\nPROFS\nWeather Modification Program\n41\nWMP\nAtlantic Oceanographic and Meteorological Laboratory\n47\nAOML\nPacific Marine Environmental Laboratory\n69\nPMEL\nGreat Lakes Environmental Research Laboratory\n93\nGLERL\nGeophysical Fluid Dynamics Laboratory\n111\nGFDL\nNational Severe Storms Laboratory\n121\nNSSL\nWave Propagation Laboratory\n137\nWPL\nAir Resources Laboratory\n151\nARL\nAeronomy Laboratory\n187\nAL\nSpace Environment Laboratory\nSEL\n209\nCooperative Institutes\nCooperative Institute for Marine and Atmospheric Studies\n227\nCIMAS\nCooperative Institute for Mesoscale Meteorological Studies\n233\nCIMMS\nCooperative Institute for Research in the Atmosphere\n233\nCIRA\nCooperative Institute for Research in Environmental Sciences\n34\nCIRES\nJoint Institute for Marine and Atmospheric Research\n242\nJIMAR\nJoint Institute for Study of the Atmosphere and Ocean\n246\nJISAO\nAppendix: Acronyms and Abbreviations\n249\niii","These are highlights of Laboratory accomplishments and\nabbreviated summaries of immediate objectives. More\ncomprehensive and detailed descriptions of activities,\nresults, and plans may be found in the Laboratories' 1\nannual reports (which may be obtained directly from\nthe Laboratories) and in the open literature. Inter-\nested readers are referred to the annual Environmental\nResearch Laboratories Publication Abstracts.","ENVIRONMENTAL\nRESEARCH\nLABORATORIES\nThe Environmental Research Laboratories (ERL) are organized within NOAA's\nResearch and Development arm and have their headquarters in Boulder, Colo.\nThey include major units located throughout the United States:\nAeronomy Laboratory (AL)\nBoulder, Colo.\nAtlantic Oceanographic and Meteorological Laboratory (AOML)\nMiami, FLa.\nAir Resources Laboratory (ARL)\nRockville, Md.\nGeophysical Fluid Dynamics Laboratory (GFDL)\nPrinceton, N.J.\nGreat Lakes Environmental Research Laboratory (GLERL)\nAnn Arbor, Mich.\nNational Severe Storms Laboratory (NSSL)\nNorman, Okla.\nPacific Marine Environmental Laboratory (PMEL)\nSeattle, Wash.\nSpace Environment Laboratory (SEL)\nBoulder, Colo.\nWave Propagation Laboratory (WPL)\nBoulder, Colo.\nEnvironmental Sciences Group (ESG)\nBoulder, Colo.\nIn addition, institutes administered jointly by ERL and universities undertake\nresearch for ERL. ERL also sponsors research through contracts and grants to\nuniversities, State and Federal agencies, and private enterprise.\nERL's research program includes fundamental technology development and\nservices to the public. Samples of outputs are Doppler radar technology (to\nimprove tornado detection and warnings), mathematical models (to predict cli-\nmate variations), ocean current forecasts (to minimize ship operation costs),\nobservations of ocean upwelling (to maximize fish catches), and solar activity\nforecasts (to protect, for example, radio communications).\nUsers of ERL outputs include the atmospheric, marine, and space research\ncommunities, NOAA service components (National Weather Service, National Ocean\nService), Federal, State, and local governments, and the private sector.\nThe ERL program is broad, embracing studies relating to the oceans and\nGreat Lakes, the lower and upper atmosphere, and the solar-terrestrial environ-\nment. Studies and activities focus in seven subject areas:\nWeather observation and prediction\nAir quality research and technology development\nClimate research\nSolar-terrestrial research and services\nMarine observation and prediction\nMarine assessment research and services\nMarine resources research and services\nThe following summary of ERL research is organized in terms of these subject\nareas. Succeeding sections discuss the accomplishments and plans of the\nindividual Laboratories and other units. The Appendix lists acronyms and\nabbreviations used in those sections.\n1","WEATHER OBSERVATION AND PREDICTION\nWeather Observation and Prediction includes programs of AL, AOML, GFDL,\nNSSL, WRP, PROFS, WPL, and the joint institutes. These programs interact di-\nrectly with those of GLERL's Ocean and Lake Services R&D and with Solar Ter-\nrestrial Research and Services programs dealing with the lower and upper\nphysical boundaries of the atmosphere, with Air Quality programs relating to\nthe short term, and with Climate programs relating to the long term. The\nprograms include these elements: research on observational systems, modeling\nand prediction, severe storms, hurricanes, sea-air interaction, cloud and\nprecipitation processes, and mesoscale meteorology, and transfer of tech-\nnology.\nObservational Systems\nA research facility used in several program elements is the Boulder Atmos-\npheric Observatory, which includes a 300-m-high meteorological tower and asso-\nciated remote sensors. The atmospheric research conducted at this facility\nincludes micrometeorological and boundary layer studies, and meso-beta-scale\n(i.e., scales up to 200 km) research. The latter research includes downslope\nwind situations and studies of clouds and precipitation under upslope condi-\ntions.\nThe most versatile and successful observational tools are radar and lidar.\nTechniques being developed using radar remote sensing include optical and\ninfrared scintillation for measurement of wind (path-averaged values), refrac-\ntivity fluctuations, heat and moisture flux, rainfall rate, and drop-size\ndistribution. Doppler radar research on flow and precipitation fields within\nsevere thunderstorms has led to the interagency NEXRAD Program, whose goal is\nto design a new national Doppler radar network during the 1980's. In develop-\nment are optical and infrared lidar techniques for the remote measurement of\nwinds, temperature, humidity, and aerosols; passive microwave techniques for\nthe measurement of temperature and humidity profiles and cloud liquid; and\nactive radar techniques for the measurement of winds, clouds, precipitation,\nturbulence, and refractivity fluctuations. As techniques are developed, they\nare transferred to operational programs.\nA high-power, large antenna VHF Doppler radar technique for measuring\nwinds, turbulence, and gravity waves in clear air is being used at Poker Flat,\nAlaska, to measure these parameters continuously throughout the lowest 100 km\nof the atmosphere. Radar systems at Platteville, Colo., and Stapleton Field,\nDenver, and three other sites in Colorado are used by PROFS for real-time\nwindspeed and wind direction data, and are research prototypes for the\nProfiler system being developed, to replace the radiosonde wind-profiling\ncapability. Microwave radiometer devices for vertical sensing of water vapor\nand liquid water are also part of the PROFS Colorado network and are research\nprototypes for the Profiler system, to replace the radiosonde temperature and\nhumidity profiling capability.\nRemote techniques are being developed to map electrical discharges in\nthree-dimensional space, for correlation with storm dynamics and precipitation\nand with changes in electric fields.\n2","Modeling and Prediction\nModeling and prediction programs in ERL have several goals. In the large\nscale, goals include the following: to develop or improve atmospheric pre-\ndiction models suitable for the 5- to 30-day time frame (for application in\nthe National Weather Service), to identify external forcing mechanisms that\nmodels must include to simulate the evolution of macroscale atmospheric dis-\nturbances over the range of several weeks to 4 months, and to search for a\nphysically based, probabilistic approach for long-range simulation of atmos-\npheric variations. In the mesoscale, goals include understanding of hurricane\ndynamics, including the genesis, development, and decay of tropical depressions\nand the study of small-scale features within hurricane systems; production of\naccurate numerical simulations of mesoscale processes, to understand what role\nsynoptic-scale parameters play in hurricane generation and evolution; under-\nstanding of internal gravity waves including their generation, interaction,\nand breakdown; and development of three-dimensional numerical models.\nSevere Storms\nThe severe-storms research acquires severe-storm data with specially\ndeveloped instruments and analyzes these and conventionally acquired data to\nobtain a more comprehensive understanding of severe storms, to develop models\nof convective storms, to compare models with observations, and ultimately to\nimprove prediction of severe storms.\nThe instrumentation developed in ERL for this research includes a 50-\nstation surface network, an instrumented television tower, two large 10-cm\nDoppler radars, an atmospheric electricity measurement system, two 3-cm\ntransportable Doppler radars to measure three-dimensional velocity fields in\nconvective storms, and pressure sensor arrays to detect and monitor gust fronts\nin the vicinity of airports.\nHurricanes\nThe hurricane research element involves three major activities. (1) The\nhurricane field research program's basic objective is to assemble the descrip-\ntive data needed to support analytical and theoretical studies that are de-\nsigned to provide the best possible understanding of the structure and behavior\nof hurricanes. The ultimate purpose is to improve prediction of hurricanes.\nThe program makes use of air- and ground-based radar, aircraft, and satellite\nobservations. Flights are made for approximately 200 hours per year using the\nuniquely well-equipped NOAA aircraft. Investigations include boundary layer\nprocesses, evolution of convection and associated wind fields, hurricane motion\nand internal dynamics, cloud microphysics, and flow characteristics in and\nnear the eyewall and spiral rainbands. (2) The hurricane modeling activity is\ndeveloping or improving models for hurricane track prediction, mesoscale dynam-\nics, and statistical track forecasting. (3) The hurricane research project\ninvolves a combination of efforts on pre-hurricane disturbances, hurricane\ngenesis and development, hurricane climatology, general tropical meteorology,\nradar precipitation measurement, analysis of Seasat satellite data, and\nhurricane sea-air exchange processes.\n3","Sea-Air Interaction\nThe sea-air interaction element involves the experimental study and\nnumerical modeling of sea-air interactions, especially under extreme weather\nconditions such as hurricanes. The experimental studies use a series of air-\ncraft observations of sea-air (or lake-air) interactions, such as surface wind\nand wave fields under a wide range of meteorological and coastal conditions.\nThese observations are compared with the wave and storm surge predictions by\nmodels in order to validate or improve the models.\nCloud and Precipitation Processes\nResearch on cloud and precipitation processes involves numerical modeling\nof the experiments in convective clouds to predict precipitation and phenomena\nsuch as downbursts that are hazards to aviation. In support of the experi-\nmental programs, optical, infrared, and microwave radar and lidar systems are\nused to measure cloud-echo intensities at three optical and three radio fre-\nquencies as a function of three-dimensional space and time. These echo-\nintensity fields can be measured as a function of both wavelength and polariza-\ntion. The Doppler effect is used at radio and optical frequencies to deter-\nmine velocity fields and fields of turbulent kinetic energy dissipation rates.\nThe multifrequency approach provides information on droplet size, and the dual\npolarization capabilities permit identification of the cloud or precipitation\nparticles as spherical water droplets or nonspherical ice crystals. Microwave\nradiometric techniques are used to measure line integrals of cloud liquid water\nand water vapor.\nCloud Physics Research and Technology Development\nNOAA conducts cloud physics research on hurricanes and related convective\ncloud systems, and the acidity of precipitation. Although the last actual\nseeding of a hurricane was in 1969, annual investigative field programs are\nconducted in which the research aircraft penetrate hurricane circulations to\ngather data on the structural characteristics of hurricanes, including cloud\nmicrophysical data and digital radar data. The observational efforts are com-\nplemented by a strong program that is developing numerical models of hur-\nricanes.\nThe Federal-State Cooperative Program is developing criteria for the\neffective evaluation of operational cloud seeding. The research and develop-\nment needed to establish these criteria are carried out through contracts to\nfive states under a Congressional mandate. NOAA manages the contracts and\ncoordinates the research.\nThe program provides cost-effective research opportunities to develop\ntechnologies that address goals in agriculture, energy, and water resources.\nCurrent activities include studies on midwestern summer rainfall enhancement\nfor corn and soybean production, by Illinois; the importance of western seed-\ning programs to water supplies in downwind acid-rain regions, by Nevada; the\nphysics of hailstorms and the enhancement of rain over the Great Plains, by\nNorth Dakota; and the enhancement of intermountain snowfall for irrigation and\nenergy uses, by Utah.\n4","Mesoscale Processes\nThe mesoscale research includes basic and applied research on mesoscale\nprocesses of the atmosphere, with particular emphasis on large meso-alpha-scale\nconvective complexes. This includes work to improve the understanding of\nexcessive convective rainfall and to develop techniques for forecasting flash-\nflood-producing storms. Other activities are development of mesoscale numer-\nical models, conduct of theoretical and diagnostic studies, analyses of meso-\nscale weather systems, participation in meteorological field experiments, and\nstudies of the microstructure and turbulence of the atmospheric boundary layer\nusing airborne and remote-sensing measurement techniques.\nTechnology Transfer\nERL develops and tests operational sensing systems that are transferred\nto service components of NOAA such as NWS, and to other Federal agencies such\nas the Federal Aviation Administration (FAA). Doppler radar for identification\nand warning of severe thunderstorms and tornadoes has been tested for the Air\nForce and the FAA. These tests indicate that Doppler radar reliably detects\nthe greatest majority of destructive tornadoes tens of minutes before they\nproduce damage. The flash-flood-forecasting research is conducted in close\ncooperation with NWS.\nIn the PROFS program, NWS, NESS, and ERL cooperate to improve local\nweather information service systems for NWS. System design incorporates many\nof the advances mad in the past decade in satellite- and ground-based remote\nsensing, in automated and surface weather stations, in data processing and\ndisplay, in mesoscale analysis and forecasting, and in dissemination of data\nand forecasts.\nAIR QUALITY RESEARCH AND DEVELOPMENT\nThe goal of this program of research in meteorology and air and precipi-\ntation chemistry is to determine sources, transport and dispersion, and fates\nof trace constituents and pollutants to enable government and industry to\nreduce adverse impacts and maintain the chemical health of the atmosphere.\nAir quality has a great effect on human health and ecology, and possible\nshort-term and long-term effects on global weather/climate. NOAA has the re-\nsponsibility to develop measurement techniques for important atmospheric\nconstituents, to measure the spatial and temporal distribution of the constit-\nuents, to measure cross sections for the interactions involving and affecting\nimportant atmospheric constituents, and to perform modeling studies to under-\nstand the physics and chemistry of the atmosphere and the long-term impact of\nhuman-induced changes. NOAA carries out the tasks of ascertaining the sources\nof pollutants in nature and in human activities. It explores the fate of\natmospheric constituents such as aerosols, particulates, and gases, and as-\nsesses the geophysical consequences of energy production. This research pro-\nvides the scientific basis for regulating industrial, agricultural, and other\npolluting but economically necessary activities.\n5","The Aeronomy Laboratory (AL) conducts research on chemical and physical\nprocesses of the Earth's atmosphere to advance the capability of monitoring,\npredicting, and controlling the quality of the atmosphere. The research con-\ncentrates on the stratospheric and tropospheric regions of the atmosphere.\nResearch methods involve both in situ and remote measurement of critical\natmospheric parameters, including chemical and composition and dynamic prop-\nerties, such as wind velocities, turbulence, and wave motions. Theoretical\nprograms in atmospheric photochemical modeling and in atmospheric dynamics and\ntransport support the observation programs. An experimental laboratory\nchemical kinetics program supports the theoretical photochemical modeling\nprogram and also supplies input for the development of new atmospheric moni-\ntoring and measurement technology.\nThe Air Resources Laboratory (ARL) operates baseline stations for meas-\nuring atmospheric constituents important in air quality variation (see also\nClimate Research); conducts field and laboratory investigations into the phy-\nsics and chemistry of formation of natural and anthropogenic particles and\ngases, the dispersion, transformation, and sinks of these particles, and the\nscavenging of particles and gases by clouds; and develops and disseminates air\nquality simulation models for inert and reactive pollutants on all temporal\nand spatial scales.\nThe Wave Propagation Laboratory (WPL) and the Geophysical Fluid Dynamics\nLaboratory (GFDL), respectively, contribute remote-sensing measurement and\natmospheric circulation and chemical modeling capabilities to aid in solution\nof the air quality problems of transport and transformation. Currently the\nfocuses of their air quality programs are Ozone, Acid Rain, Transport and\nDiffusion, and Modeling. There is a close association with the program of\nGeophysical Monitoring for Climatic Change (GMCC; see Climate Research) and\nthe programs of Weather- and Marine Observation and Prediction, and\nSolar-Terrestrial Research and Services.\nOzone\nIn recent years, the chemistry of the stratosphere has been of great\ninterest because of the recognition of human potential for inadvertently\naffecting the ozone layer, with disastrous consequences. First, the pos-\nsibility of an ozone reduction from water and nitrogen oxides released in\nstratospheric flights of supersonic transports was considered. This problem\nbrought worldwide attention to the potential for global air pollution prob-\nlems. More recently, chlorine-containing halocarbons and nitrogen fertilizers\nhave been labeled potential threats to stratospheric ozone. In addition to\nthe effects biological systems, ozone loss may also precipitate climatic\nchanges.\nThe ARL monitoring program calibrates ozone measurement devices used at\nthree ARL sites and other worldwide ozone-monitoring sites. AL is conducting\nmeasurement and studies of transport and chemistry affecting ozone. One radi-\ncal important in ozone chemistry is NO 3 formed when nitrogen dioxide reacts\nwith ozone. Research is improving our understanding of the chemistry of NO\nrequired for interpreting the role of nitrogen oxides in the stratosphere and\ntroposphere.\n6","There is still considerable uncertainty about pathways of pollutants to\nthe stratosphere, where ozone is important to ultraviolet absorption of solar\nradiation. AL has demonstrated that towering cumulus development in the west-\nern Pacific is a source of stratospheric water vapor, and hence a potential\npath for pollutants to enter the stratosphere and interact with the ozone.\nFurther quantitative measurements are in progress.\nAL has also developed laser magnetic resonance and laser-induced fluor-\nescence techniques to measure important reaction rates and cross sections.\nThe fluorescence technique is being used to measure various NO 3 reaction pa-\nrameters and kinetics. In other measurement programs tropospheric profiles if\nnitrogen oxide and nitrogen dioxide have been measured with sensitive chemilum-\ninescent detectors. Current measurements relevant to ozone chemistry include\nballoon-borne measurements of global atmospheric profiles of N 2 NO, NO2, CO,\nH20, O3, and chlorofluoromethanes.\nAcid Rain\nThe principal issues in the Acid Rain program are (1) the gradual acidi-\nfication of surface waters and soils by acid rain and dry deposition, and (2)\nthe transboundary (especially U.S./Canada) transport of acidifying pollutants.\nNOAA is one of the lead agencies in the National Acid Precipitation Assessment\nProgram (NAPAP) and has the principal research responsibilities in three areas:\n(1) Assessing natural sources or causes of acidity and their importance\nrelative to human-activity sources, to facilitate control\nstrategies.\n(2) Defining and assessing atmospheric processes of transport, disper-\nsion, and transformation that link emissions of pollutants with acid\ndeposition.\n(3) Interpreting deposition mechanisms that bring acidic pollutants to\nthe Earth's surface, and assessing the consequent severity and ex-\ntent of the acid deposition phenomenon.\nARL is in the process of setting up a series of monitoring sites to de-\ntermine the quantity and type of acid material that is being deposited in\nNorth America. One of these, operated by AL, is a remote site at the 10,000-ft\nlevel on Niwot Ridge, in Colorado. This location has the valuable feature\nthat, depending on wind condition, it can be used to examine both the \"clean-\nair\" from the west and the relatively polluted air from the Denver metropolitan\narea to the east. The Niwot site is being used to test the current understand-\ning of the photochemistry whereby NO 3 is formed from NO and NO. It has been\nfound that, for given NO2 levels, HNO 3 levels are higher in summer than in\nwinter. Other studies permit estimates of the seasonal dependences of the dry\nremoval rates of HNO3, which appear to be much faster in summer than winter.\nNatural sources of acid rain precursors have been found in the Gulf and\nthe North Pacific Oceans by AOML and PMEL scientists. Research on these nat-\nural sources includes water and atmospheric sampling for volatile sulfur\nspecies to assess exchange rates and source/sink relationships for these\ngases, sulfur metabolism studies at sea using radio-sulfur and natural\nphytoplankton populations, and studies of the influence of ocean-emitted gases\n7","on the acidity of marine-derived precipitation. In addition to this research,\nARL is measuring pre-acidic material transported across coastal boundaries.\nTransport and Diffusion\nThe problem of transport and diffusion is important to a larger class of\nair quality programs. NOAA research in this area includes field programs and\nmodeling. Major field programs in progress or completed are the Cross-\nAppalachian Tracer Experiments (CAPTEX 1982 and 1983), the Atlantic Coastal\nUnique Regional Atmospheric Tracer Experiment (ACURATE), and the Metropolitan\nTracer Experiment (METREX). These are multi-agency experiments and include\nARL, WPL, and NWS from NOAA. The results of these field programs are being\nused to develop and verify models that can determine the effect of surface\nroughness and complex mountainous terrain on the measurement of air trajec-\ntories, and the effects of atmospheric anomalies (i.e., inversions) on trans-\nport and diffusion.\nModeling\nThe main goals of ERL modeling research is to understand the formation,\ntransport, and chemistry of atmospheric trace constituents. Such\nunderstanding requires judicious combinations of theoretical models and\nspecialized observations. The understanding gained will be applied toward\nevaluating the sensitivity of the atmospheric chemical system to human\nactivities. Ongoing chemical modeling work at GFDL includes analyses of\natmospheric nitrous oxide, reactive nitrogen (natural plus anthropogenic), and\ntropospheric ozone. Models are being developed to include a number of trace\nconstituents simultaneously. This capability will be used to run\ninterdependent experiments involving ozone and its precursors, partitioned\ncomponents of total reactive nitrogen, carbon monoxide, and so forth.\nARL is developing transport models to simulate and/or predict local,\nregional, and global transport and diffusion of pollutants injected into the\natmosphere. The models are used to evaluate the environmental effects of\nvarious kinds of energy production (e.g., nuclear fuels or fossil fuels) and\nof volcanic eruptions, and to predict the path of radioactive debris from\nvarious atmospheric nuclear tests. In the acid rain program, a major goal is\nto establish the source-receptor relationships between sulfur emissions and\nacid deposition.\nCLIMATE RESEARCH\nClimate Research includes programs involving eight Laboratories, the\nOffice of Programs, the Office of Aircraft Operations, and four joint insti-\ntutes. The climate programs interact directly with other major programs such\nas Air Quality, Solar-Terrestrial Research and Services, and Ocean and Lake\nServices, and on the short-term time scale, with Weather Observation and\nPrediction. Elements of the climate programs include ocean-atmosphere\nstudies; observation and analysis of solar, atmospheric, and stratospheric\nvariability; and climate modeling.\n8","Ocean-Atmosphere Studies\nThe ocean-atmosphere studies include several projects. One of these, the\nEquatorial Pacific Ocean Climate Studies (EPOCS) program is investigating the\nphysics and dynamics of the coupled ocean-atmosphere system in the equatorial\nPacific as part of the international Tropical Oceans Global Atmosphere (TOGA)\nprogram. Understanding this system is vital to comprehending global fluctua-\ntions of climate on interannual time scales. A broad spectrum of oceanographic\nand atmospheric parameters is being monitored by a variety of sensors to create\nan integrated data base. Satellites are continuously monitoring winds and sea\nsurface temperatures. Research vessels are using XBT's and current profilers\nto determine vertical thermal and dynamic cross sections. Moored arrays at or\nnear the Equator are used to determine the major time scales of variability of\nocean parameters such as current, temperature, and salinity. Drifting buoys\nare used in the Pacific equatorial current system to determine the larger scale\ncurrent patterns as well as other spatially distributed parameters. Other\nprojects are using aircraft to measure vertical fluxes of heat, moisture, and\nmomentum over the tropical Pacific.\nThe Subtropical Atlantic Climate Studies (STACS) is another major program,\nwhich seeks to identify the processes that contribute most to the poleward\ntransport of heat in the North Atlantic Ocean and to develop the technology to\nmonitor these processes operationally. The initial emphasis of STACS has been\non developing techniques to monitor the mass transport and heat content of the\nFlorida Current. Several techniques are being tested to determine the most\nefficient approach for long-term monitoring of the Florida Current. Among\nthese are electromagnetic induction measurements from communications cables,\nuse of coastal tidal stations, Doppler radar observations of surface flow, and\nacoustic measurements.\nIn addition to EPOCS and STACS, a broad range of research is conducted on\nthe temporal and spatial variability of water mass structure, sea level, cur-\nrents, and general circulation of deep ocean and coastal waters. Vertical\nmixing processes in the upper ocean, wind-generated response of middle-latitude\nupper ocean currents and temperature fields, and methods of inferring surface\nwind stress fields from satellite data are specific concerns of projects within\nthe climate program.\nIn a technology development project, the potential of using low-frequency\nsound sources and detectors (acoustic tomography) to measure the structure of\nthe ocean is being investigated.\nClimate Variability\nProjects relating to climate variability include airborne measurement of\nsolar radiation over the equatorial Pacific; construction of a global data set\ndescribing climate variations over the past 150 years; determination of the\nintensity and time scales of variations in the solar ultraviolet radiation as\na function of wavelength in the 110- to 400-nm range; and determination of the\nsignificance of such variations in molecular dissociation atmospheric chemis-\ntry, upper atmosphere heating, and measurements of atmospheric constituents.\nGlobal levels of atmospheric trace constituents that have significant effect\non the Earth's radiation budget, including carbon dioxide, ozone, aerosols,\n9","and water vapor, are monitored and analyzed. Four monitoring stations (Alaska,\nHawaii, Samoa, and South Pole)--one tropical and one high-latitude in each\nhemisphere--provide baseline observations for monitoring global air quality.\nThese stations are supplemented by several specialized monitoring networks\noperated by groups from the United States and other nations. These monitoring\nstations, which perform measurements for research related to climate change,\nare supported by instrument calibration and development in ERL. Analysis and\ninterpretation of the data from the stations emphasize air quality changes,\nwith special emphasis on carbon dioxide, that might affect climate. ERL under-\ntakes additional reimbursable work involving the measurements of solar radia-\ntion, temperature, and other parameters above a forest canopy in order to\nimprove understanding of the biosphere as a component of the climate system.\n(Atmospheric chemistry and stratospheric sampling programs, which also relate\nto climate research, are described in the Air Quality section.)\nClimate Modeling\nThe modeling element is focused on constructing mathematical models of\nthe atmosphere, the oceans, and the coupled fluid system that simulate the\nlarge-scale features of climate variability. Emphasis in atmospheric studies\nis on dynamical interaction between large-scale wave disturbances and the\ngeneral circulation of the atmosphere, identification of the physical and\ndynamical mechanisms that maintain climate and cause its variation, and eval-\nuation of the impacts of human activities on climate. The ocean circulation\nstudies are also central to climate research. They focus on the large-scale\nresponse of the ocean to atmospheric forcing over a range of time scales from\nweeks to decades, ocean observational studies of the density structure and\nfields of various tracers, development of models of the world's oceans, in-\nterpretation of results in terms of a coherent hydrodynamical framework, and\ndevelopment of a capability to predict the large-scale behavior of the world's\noceans in response to changing atmospheric conditions. The aim of ERL's obser-\nvational studies is to identify and evaluate the physical processes by which\natmospheric and oceanic circulations are maintained and to compare observa-\ntional results with diagnostic studies of atmospheric and oceanic models.\nSOLAR TERRESTRIAL RESEARCH AND SERVICES\nThe solar-terrestrial program is accomplished in SEL. The program is\nunique in ERL because it contains both research and service components, and\nbecause the major user of the research program is the service program. The\nsolar-terrestrial program interacts strongly with other government agencies,\nespecially DOD and NASA. The goals of the program are to promote efficient,\nsafe, and economic utilization of extraterrestrial space for civilian and\nmilitary activities, vehicular operations, and communications; to support\neffective operation of essential public services that are subject to disrup-\ntion by magnetic storms or solar events; and to increase understanding of the\nphysical processes in the near-Earth space environment and their relation to\nhuman activities.\nThe program maintains continuous operation of the Space Environment\nServices Center (SESC) at Boulder, Colo., for monitoring and predicting solar\n10","activity and events in the upper atmosphere and their effects on communica-\ntions, electric power systems, and air and marine navigation; and to maintain\ncontinuous acquisition and processing of data from space environment monitors\non the Geostationary Operational Environmental Satellites (GOES) and the polar-\norbiting TIROS-N and NOAA satellites. SESC, jointly operated with the United\nStates Air Force Weather Service, is both the national and international center\nfor operational space and upper atmosphere information. SESC provides fore-\ncasts and warnings of solar disturbances and their effects to government\nagencies, industries, universities, foreign governments, and other foreign and\ndomestic users. These forecasts and warnings help to prevent failure of some\naircraft and marine navigation and communications systems at high latitudes,\nand they help to improve the efficiency of all telecommunications systems, the\neffectiveness of military operations and solar-disturbance-sensitive research\nprograms, and the reliability of electric power networks. Real-time observa-\ntions of the Sun and space environment are the basis for forecasts and warn-\nings.\nResearch is undertaken to understand and model the fundamental physical\nprocesses responsible for the observed energy release, in the form of electro-\nmagnetic radiation and charged particles, from the solar surface during solar\ndisturbances; the propagation and modification of this energy through inter-\nplanetary space to the near-Earth environment; the transfer of this energy\ninto the Earth's magnetic field; and the behavior and subsequent effects of\nthis energy within the magnetosphere, the ionosphere, and the upper atmos-\nphere. These studies use data from satellites, rocket-launched instruments,\nand ground stations. The ultimate goal of this research is to develop numer-\nical models that can be used by SESC to predict, with increasing accuracy, the\ntiming and geographic distribution of the effects of solar disturbances on the\nEarth's environment and on human activities.\nMARINE OBSERVATION AND PREDICTION\nThe ocean and lake observation and prediction program is accomplished at\nAOML, GFDL, GLERL, PMEL, WPL, and joint institutes. The program interacts\nstrongly with the Climate, Air Quality, and other marine program areas. This\nresearch improves the capability for providing services to the marine community\nthrough increased understanding and improved observations of the behavior of\nthe atmospheric boundary layer over the ocean, the wave and current motions\nin surface layers, and the physical properties of the surface and subsurface\nwaters of the ocean. Subjects of study include winds, waves, storm surges,\nocean properties, tsunamis, and ice.\nWinds\nERL conducts research to improve the observation and forecasting of\nhazardous winds that affect homeowners, recreational boaters, and oil and gas\nindustry, fishing, and commercial transportation. Surface winds provide the\ndriving force for the generation of other phenomena such as waves, currents,\nupwelling, and storm surges. Until the wind stress, which provides the major\ndriving force, can be measured directly, it must be computed from the wind\nfield in the boundary layer immediately above the water surface. Since winds\n11","measured at coastal weather stations are often not representative of nearby\nover-the-water winds, increased emphasis is being placed on developing in situ\nand remote-sensing techniques for directly measuring the latter.\nWaves\nResearch on marine waves is conducted to improve forecasts and warnings\nof hazardous coastal wave conditions. Waves are generated by the action of\nthe wind stress on the surface of the water. The highest priority research is\nin the prediction of wave fields for coastal and continental shelf regions.\nThis prediction capability requires knowledge of the characteristics of the\nwave field moving from the deep oceans, and of modification of the deepwater\nwave field as it moves into shallow waters and onto the shore. Improved pre-\ndiction of deepwater waves requires an increased understanding of the processes\naffecting the generation and growth of these waves. Present prediction\ncapability is being significantly improved by the development and application\nof both discrete spectral and parametric models. In addition to improving the\nmodels used for wave predictions and improving the understanding of wave\ndynamics, this research is developing and applying new techniques such as\nground-based radar, airborne imaging radar, airborne laser wave profilometry,\nand satellite observations to observe the sea state or parameters for predic-\nting sea state.\nStorm Surges\nStorm surge research develops models that predict water impacts due to\nstorms on coastal regions. This type of information is needed for both coastal\nplanning and for real-time forecast and warning. The planning activities\ninclude both the establishment of criteria to guide coastal development and\nthe preparation of plans for evacuating coastal communities. Hurricanes and\nother violent wind storms cause surges of water that are often 15-20 ft above\nthe normal water level and are especially dangerous when combined with a high\ntide or high-wave conditions. Present techniques for forecasting the timing,\nextent of coastline affected, and magnitude of the inundation are inadequate\nto ensure the safety of coastal populations. Research to address these\ndeficiencies is considering topographically complex areas like bays and inlets,\nand complicating factors such as inhomogeneities in the wind field, variations\nin water depth offshore, and the effects of waves and currents.\nOcean Properties\nResearch on properties of oceans involves observations of currents, up-\nwelling, and thermal properties. Improved understanding and forecasts of\nocean currents are an important focus of research. Ocean currents play key\nroles in shipping, fishing, pollutant transport, search and rescue operations,\nand climate variability. For example, forecasts of the short-term location\nand movement of the Gulf Stream could increase operational efficiency of ships\nand oil tankers. Increased efficiency in fishing operations and management of\nfisheries stocks is dependent on improved knowledge and forecasting of shelf\ncurrents and upwelling conditions. Knowledge of currents is essential in fore-\ncasting the movement of pollutants such as oil and chemicals released into\n12","marine waters. Knowledge of upwelling conditions is necessary to forecast\ncoastal fog. Research on improving the accuracy of measuring and forecasting\nsea surface parameters is also undertaken in this program element. More\naccurate and higher resolution measurement of sea surface temperature fields\nwould allow more accurate location of boundaries of different water masses and\nupwelling regions, and establishment of air-sea temperature differences, which\naffect the stability of the atmospheric boundary layer over the water and, in\nturn, the surface wind field that generates waves and currents.\nTsunamis\nA goal of ERL tsunami research is improved prediction and monitoring of\nearthquake-induced ocean waves. These waves can travel great distances at\nhigh speeds and can cause extensive damage to coastal communities. Improving\nforecasts and warnings requires the capability to determine in real time the\nexpected tsunami height and runup at various coastal locations. Qualitative\nforecasts based on historical data are now possible but quantitative forecasts\nare not. Key areas of research include tsunami generation, numerical tsunami\nmodeling, and instrument development to monitor micro-tsunamis for analytical\nand numerical models and to detect tsunamis before landfall for operational\nwarnings. Information obtained is being incorporated into an operational warn-\ning system to provide reliable (low false-alarm rate) and accurate warnings.\nIce\nIce research in ERL seeks to improve monitoring and prediction of growth,\nmovement, and breakup of ice in the Bering Sea, along the Alaskan Arctic coast,\nand in the Great Lakes. In the Great Lakes, accurate forecasts of ice thick-\nness and extent in nearshore areas and connecting channels would allow exten-\nsion of the commercial navigation season and improved design of nuclear\nreactor coolant intakes and shore property. Ice formation and growth occur by\nin-place thermal growth or movement of ice from other areas by wind and waves.\nThermodynamic models of ice cover indicate that optical properties of ice are\nextremely critical to accurate forecasts of ice cover. Hence, a knowledge of\nlight transmission, absorption, and reflection characteristics of the various\nice types common to the Great Lakes is essential for modeling, remote sensing,\nand energy budget studies. Regional models for ice forecasts are being\ndeveloped and transferred to the National Weather Service for operational use.\nThese models incorporate ice and wind dynamics and ice thermodynamics as well\nas local coastal geometries and site-specific user requirements.\nMARINE RESOURCES RESEARCH AND SERVICES\nThe marine assessment program includes contributions from AOML, GFDL,\nGLERL, PMEL, and joint institutes. ERL conducts process-oriented research to\nimprove our understanding of natural oceanic and Great Lakes systems and the\necological impacts of human-induced stresses on these systems. ERL's problem-\noriented research leads to improved assessment capabilities. ERL develops and\ntransfers scientific information to support decisions pertinent to marine pol-\nlution, exploitation of living and nonliving marine resources, water\n13","utilization, coastal power generation, and other activities affecting marine\necosystems. Research activities focus on coastal regions, estuaries, and the\nGreat Lakes. Primary topics of concern include dynamics and kinematics of\nwater circulation; transport, transformation, and fate of pollutants, and\neffects of pollutants on marine ecosystems; ecosystem and nutrient dynamics;\nthe effects of physical and biochemical processes on marine productivity;\nwater supplies, lake levels, and flows in the Great Lakes system; and the\ndevelopment and application of marine prediction models, risk analysis tech-\nniques, and advisory services.\nOcean Systems\nResearch on the effects of ocean use consists of field investigations and\nsupportive laboratory research to determine the consequences of ocean dumping\nof dredged material and municipal and industrial wastes. Emphases are on pol-\nlutant effects and the development of techniques to measure pollutants. A\ncomprehensive program of research is conducted to detect changes in the oceans\nand the Great Lakes that are caused by human activities and that my have long-\nterm adverse consequences. The research focuses on the interaction of trace\nmetals, synthetic organics, and hydrocarbons with marine ecosystems. The role\nparticulates as pollutants or as a transport mechanism for harmful compounds\nof\nis emphasized. Studies at AOML are determining which natural or pollutant\norganic materials in seawater complex or bind toxic or essential trace metals,\nand what effect such complexing or binding has on marine productivity. Other\nresearch at this Laboratory is examining the mechanisms by which particulate\nmatter in marine ecosystems functions in the transport and removal of pol-\nlutants. This research investigates the extent to which mineral and biogenic\nparticles scrub large river outflow systems of pollutants and bury them is\ndeltaic sediments, and the extent to which this burial can be reversed by re-\nsuspension events such as storms. Current work focuses on the Mississippi\nRiver outflow.\nResearch conducted by PMEL describes and quantifies the physical and\nchemical processes affecting the transport, transformation, and fate of pol-\nlutants in marine estuaries and coastal systems. Studies focus on pollutant\nlevels and distributions; chemical transformation of pollutants and uptake by\nparticulates; pollutant source/sink distributions; and estuarine and coastal\ncirculation patterns and mixing processes. The primary effort is in the Puget\nSound System. PMEL also conducts research to develop models of mass fluxes of\ntrace metals and toxic organics in coastal and estuarine systems. Research\nstresses the incorporation of information on pollutant loading and on physical\nand chemical processes obtained from field studies into dynamic models of\nwater movements and pollutant distributions and fluxes. PMEL provides in-\nformation on coastal and estuarine processes that affect the ability of marine\nsystems to accommodate contaminants without unacceptable damage. This informa-\ntion synthesizes the results of field studies and models to determine relation-\nships, useful for decision-making purposes, among pollutant types, distribution\nand levels of loading, pollutant transport and dissipative processes, and\necological consequences.\nAt GFDL, research related to the quality of the marine environment has as\nits objective the simulation of oceanic conditions in coastal zones and in\nestuaries, and the modeling of the dispersion of geochemical tracers (e.g.,\ntritium, radon) in the world oceans. Two- and three-dimensional models of\n14","estuaries such as the Hudson-Raritan and Delaware Estuaries are being devel-\noped. The response of coastal zones to transient atmospheric storms, and the\nnature of upwelling processes (which are of great importance to fisheries),\nare being studied by means of a variety of models.\nGreat Lakes Systems\nGLERL conducts research in the Great Lakes on water movement and temper-\nature, particle dynamics, cycling of toxic organics, planktonic succession,\neutrophication and nutrient cycling, and the development of environmental\ninformation services and environmental engineering models and applications.\nThe\nwater movement and temperature research develops improved climatological\ninformation (by means of observations, new instrumentation, and improved anal-\nysis) on the distribution and variability of coastal and offshore currents and\ntemperature, develops and tests improved numerical hydrodynamic models that\ncan simulate and predict lake currents and temperatures, and extends models to\nsimulate and predict the transport and diffusion of pollutants. Research in\nthe Great Lakes also emphasizes the interaction of particulates and pollutants,\nparticularly the pollutant source/sink characteristics of bottom sediments.\nGLERL also develops ecosystem models that simulate the passage of toxic pol-\nlutants through the Great Lakes food chain.\nA major effort at GLERL develops, tests, evaluates, and applies water\nquality and water quantity management models and improved environmental systems\nengineering methods to estimate pollutant and nutrient loading; to estimate\neffects of diversions, consumptive use, human-induced changes in lake water\nlevels, and levels and flows in the connecting channels; and to organize and\ndisseminate environmental information for decision purposes.\nMARINE ASSESSMENT RESEARCH AND SERVICES\nThe marine resources research program is accomplished through projects at\nAOML, GLERL, PMEL, and joint institutes. The program is designed to accelerate\nrational marine industrial development through research into the optimum use,\ndevelopment, and protection of living and mineral marine resources; to\nimprove, through applied research, the technologies needed for efficient use\nof marine resources; and to provide significant information on the social,\neconomic, and legal impacts of present and projected marine development.\nMarine Environmental Research\nMarine environmental research is directed toward managing and protecting\ncoastal resources in the face of increasing multiple-use conflicts. Projects\nand studies focus on understanding the effects of various uses (e.g., waste\ndisposal, industrial and commercial activities, food production, and residen-\ntial and recreation uses) on marine and estuarine ecosystems. This understand-\ning is essential to the wise use and protection of these resources.\n15","Submarine Hydrothermal Venting Systems\nERL has recently increased its research on submarine hydrothermal venting\nsystems at seafloor spreading centers in response to the growing recognition\nof the environmental importance of the hydrothermal fluids. Certainly, factors\nsuch as possible economic importance of mineralized deposits have generated\nmuch of the recent interest in processes at seafloor spreading centers. How-\never, the basic lack of understanding of the average environmental role of the\nhydrothermal fluids is the focus of ERL's research. Consequently, ERL's pro-\ngram is designed to assess the importance of hydrothermal fluids in altering\nthe physical, chemical, biological, and geological characteristics of the\nmarine environment into which the fluids are introduced.\nMarine Advisory Services\nMarine advisory services include informal education of the general public,\ntechnical advice and instruction in marine areas, identification and communica-\ntion of local marine community needs, and dissemination of research findings\nthrough seminars, workshops, publication, and personal contacts. The marine\nadvisors work with communicators to reach the general public through press,\nradio, television, and other media.\n16","OFFICE OF THE DIRECTOR\nVernon E. Derr, Director\nDeputy Director (Vacant)\nBoulder, Colorado\nDirector\nO/P\nDep. Director\nCooperative\nESG\nInstitutes\nCRP WRP PROFS WMP\nAOML\nPMEL\nGLERL\nGFDL\nNSSL\nWPL\nARL\nAL\nSEL\nThe Director, assisted by the Deputy Director, establishes basic poli-\ncies and manages the overall activities of the Environmental Research Labora-\ntories. Within the Office of the Director, the Office of Programs provides\nadvice and services to the Director as well as to the Laboratories and ESG.\nThe Office of Programs provides policy, program, and management advice and\nsupport in areas such as program planning, budgeting, and analysis; program\ncoordination and review; and implementation of management decisions. Budget,\nOD\nADP Planning and Telecommunications, and editing services are part of the\nOffice of Programs.\n17","","ENVIRONMENTAL SCIENCES GROUP\nWilliam H. Hooke\nBoulder, Colorado\nActing Director\nDirector\nO/P\nDep. Director\nESG\nCooperative\nCRP WRP PROFS WMP\nInstitutes\nAOML\nPMEL\nGLERL\nGFDL\nNSSL\nWPL\nARL\nAL\nSEL\nThe Environmental Sciences Group (ESG) plans, conducts and coordinates\nwell-defined, high-priority programs of environmental research and technology\ndevelopment, which frequently require an intensive, concerted, or inter-\nlaboratory approach for success. Research findings and technological advances\nare actively transferred to other NOAA line offices and the national user\ncommunity.\nESG currently includes the Climate Research Program (CRP), the Program\nESG\nfor Regional Observing and Forecasting Services (PROFS), the Weather\nModification Program (WMP) and the Weather Research Program (WRP). Ongoing\nCRP\nresearch and development activities are directed toward understanding climate,\nprecipitation, and convective weather processes; developing and evaluating\nadvanced environmental monitoring, forecasting, and modification technologies;\nand building environmental data bases for use by the scientific community.\nESG works with the cooperative institutes and other outside organizations to\nmeet these responsibilities.\nCLIMATE RESEARCH PROGRAM\nThe Climate Research Program (CRP) has three broad objectives:\nConstruction of a global data set to describe climatic fluctuations\nduring the past 130 years over oceans and continents.\nInterpretive diagnostic studies of those climatic fluctuations on time\nscales ranging from weeks to decades.\nConstruction of computer models of polar ice sheets to ascertain their\ndevelopment and their responses to climatic change.\n19","The research program represents a joint enterprise with the Cooperative\nInstitute for Research in Environmental Sciences (CIRES) of the University of\nColorado. CIRES enables NOAA and university scientists to collaborate on\nproblems of mutual interest, improves NOAA's links with the university\ncommunity, and facilities the participation of visiting scientists.\nAccomplishments FY 1984\nCLIMATE RECORD CONSTRUCTION\nMarine Data Base\nAll but one of 19 products from the Comprehensive Ocean-Atmosphere Data\nSet (COADS) have now been completed for the period 1854-1979, in continued\ncooperation with the National Center for Atmospheric Research (NCAR) and the\nNational Climatic Data Center (NCDC). Roughly 100 million global marine\nreports, observed primarily by \"ships-of-opportunity\", were collected, edited,\nand summarized statistically for each month of the period, using 2° latitude X\n2° longitude boxes. Sets of 2° monthly summaries and individual reports with\noutliers trimmed by a statistical process, refined from the relatively noisy\n\"untrimmed\" summaries and reports completed last year, are now available at\nNCAR.\nThe trimmed 2° monthly summaries give 14 statistics for each of 19\nobserved and derived variables. The observed variables are air and sea\nsurface temperatures, wind, pressure, humidity, and cloudiness. The\nderived\nvariables are sea-air temperature difference, evaporation, wind stress,\nsensible and latent heat fluxes, etc. The statistics include the median,\nmean, number of observations, standard deviation, and centroids of\nobservational location in time and space. Investigators who wish to use data\nin the form of individual reports have access to additional elements such as\nsea state or present weather. Decade-month summaries, inventories, and\ntrimming performance data are among the other products now available for\ndistribution by NCAR or NCDC.\nHighly Reflective Clouds\nThe Highly Reflective Cloud (HRC) data set continued to be updated during\nFY 1984. An atlas of monthly HRC frequencies for the global tropics is\nscheduled for publication in December 1984. A software package that permits\nconvenient extraction of HRC data for user-defined time and space parameters\nhas been developed. HRC data are being calibrated with the GOES Precipitation\nIndex, an independent satellite-based rainfall estimation scheme developed at\nNOAA's Climate Analysis Center.\nNorthern Hemisphere Land Data Base\nThe most extensive collection of long-term station temperature and\nprecipitation data for Northern Hemisphere land areas has been compiled under\na Department of Energy grant. A 5° X 10° latitude-longitude grid from 5°N to\n85°N has been constructed from these data for the period 1851-1983. An atlas\n20","of Northern Hemisphere temperature anomalies by season, year, pentads, and\ndecades is being produced. This work has been done jointly by CRP, the\nUniversity of Massachusetts, and the University of East Anglia (U.K.).\nDIAGNOSTIC STUDIES OF CLIMATIC FLUCTUATIONS\nEl Niño/Southern Oscillation (ENSO) Events\nData from COADS have been used in detailed studies of the evolution of\nENSO events over the past 50 years. The aim has been to delineate the\ndifferences and similarities of the nine separate events on record for the\npurpose of classifying their common features as an aid in future prediction.\nSeasonal differences in the winter and spring weather over the United\nStates and China associated with separate ENSO events are being studied to\nascertain if these are consistently related to the ENSO.\nAnalysis of the 1983 El Niño research flight data was completed and an\narticle was submitted for publication. Evidence was found of a moistening and\ndestabilization of the lower troposphere over the eastern Pacific accompanying\nthe increase of sea surface temperatures. Episodes of intense convection\noccurred relatively soon thereafter, in conjunction with the arrival of\nsurface westerlies.\nStudies of Monsoon Changes\nStudies of the spatial and temporal variability of the structure of the\nIndian monsoon focused on the differences between organized convection over\nthe subcontinent and that over the Indian Ocean. Considerable convective\nactivity is found to occur offshore, a finding that contributes to the\ndevelopment of modeling experiments of the Asian monsoon system.\nCRP\nDIAGNOSTIC STUDIES OF SYNOPTIC ASPECTS OF CLIMATE\nVariability of Convective Activity-Global Tropics\nRegional indices of convective activity in the tropics have been\nanalyzed. The indices, composed of 5-day mean HRC data for 1981-83, show an\neastward progression of the active areas of convection from the Indian Ocean\nto South America with a concomitant decrease in convection over areas to the\nwest. The eastward displacement of convection from western to eastern Pacific\noccurred in discrete jumps associated with synoptic-scale events. Possible\nprecursors to these events are being looked for in changes of the Southern\nHemisphere jet stream and subtropical high pressure belt.\nSimilar indices for the region encompassing South America indicate that\nthe intense drought in northeast Brazil during 1982-83 was a regional\nphenomenon, since the rest of tropical South America had normal or above\nnormal convection.\n21","Influence of Synoptic-Scale Systems on ENSO Development\nAnalysis of daily surface charts revealed the development of equatorial\nwesterly wind/convection episodes (WWCE) during the onset and mature phases of\nEl Niño. THese organized atmospheric circulation systems had spatial scales\non the order of 2000-3000 km and lasted typically for several weeks.\nThe WWCE's are a common feature of the climatology of the western\nequatorial Pacific. During the 1982-83 ENSO, WWCE's propagated eastward\ntoward the South American coast, finally reaching the coast in the spring of\n1983.\nAnalysis of Satellite Sounding Data in Connection with ENSO\nData from the TIROS Operational Vertical Sounder (TOVS) for the Pacific\nregion for 1982-83 have been analyzed in conjunction with other meteorological\nparameters. Preliminary results indicate that TOVS data can be useful in\ndefining fields of atmospheric moisture and stability associated with\nsynoptic-scale systems.\nTropical-Extratropical Teleconnections\nSynoptic-scale aspects of the teleconnection between the tropics and\nmiddle latitudes have been studied in an NSF-funded project. Analysis of\nupper-level winds and satellite imagery has revealed a common sequence of\nsynoptic-scale events linking transient convective outbreaks in the tropical\nPacific, disturbances on the subtropical jet, and cyclones over North America.\nThis synoptic sequence occurred repeatedly during the 1982-83 \"El Niño\" winter\nseason, and may be a factor in the storm climatology of the United States.\nICE SHEET MODELING\nA joint project with the University of Melbourne, Australia, exploring\nthe possibility that enhanced CO2 concentrations would lead to accelerated\nflow (\"surges\") from the polar ice sheets, got under way with DOE funding at\nthe beginning of 1984. As a basis for modeling, the complete physical\ncharacteristics of the Ross Ice Shelf drainage basin have been established on\nthe assumption of steady state (\"zero net mass balance\"). The resulting ice\nflow velocities have been used for a parameterization of basal sliding, which\nwill be tested with measurements now being made on one ice stream in a\nNASA-NSF project. The only existing model for self-induced surging of\nglaciers has been used to determine changes in temperatures and accumulation\nthat could get the ice stream into a surging mode.\nMISCELLANEOUS PROJECTS\nFluxes of Heat, Water Vapor, Momentum, and CO2 Over the Tropical Oceans\nBoundary layer studies of the marine atmosphere in progress for the past\ncouple of years were continued. A new sampling technique has been developed\nand used to investigate the statistics of updraft and downdraft events. The\nanalysis has provided information on event size and number, as well as the\n22","conditional averages of the meteorological variables and flux contributions.\nThe results provide new insights into the processes that transport heat,\nmoisture, and momentum on scales ranging from 10 m to a few kilometers. The\nultimate goal is to develop a parameterization of these transports in the\nsubcloud and cloud layers, based on large-scale data obtained from remote-\nsensing platforms, such as satellites.\nThese results are important for understanding the modifications to air-\nsea transfers due to large SST anomalies associated with ENSO.\nAnalysis of Climatic Variability, Population Increases, and Water\nSupplies in the Western United States\nThe climate of the western United States tends to alternate between wet\nand dry regimes. Over the past 25 years, population in the region and water\nconsumption have doubled. Although great steps have been taken to prepare for\ndrought-induced water shortages through greatly expanded reservoir capacity,\nthe greater demand and projections for yet larger increases have also raised\nthe region's sensitivity to drought. On the other hand, the filling of the\nreservoirs in the western states has increased the danger from flooding due to\nprolonged periods of above-normal precipitation, particularly during spring\nrunoff.\nStudies are under way to delineate the temporal and spatial characteris-\ntics of historical wet and dry periods in the Colorado River and Great Salt\nLake Basins, to aid in the development of strategies to mitigate future\nclimate-related disruptions of water supplies in this region.\nPlans FY 1985\nCLIMATE RECORD CONSTRUCTION\nCRP\nMarine Data Base\nSubject to funding approval, work is planned to update the Comprehensive\nOcean-Atmosphere Data Set (COADS), including quasi-real-tim monitoring of\nclimatic indices; refine some products for ease of use; and explore aspects of\ndata reliability using high-quality or high-density COADS subsets.\nThe first COADS release covers the period from 1854 to 1979. A second\nrelease is planned, which will expand the data set to include the years\n1980-84. Individual reports for 1980-82 will be available after the first\nyear of work. The completed database will include as many logbook or Global\nTelecommunication System (GTS) reports as are available, and will be produced\naccording to standard COADS specifications. In parallel, a purely GTS-based\ndata set will be assembled and analyzed in quasi-real-time, with emphasis on\nproviding a monthly set of climatic indices.\nAlthough they were designed with the goal of achieving relatively compact\nsize together with ease-of-use on a variety of computers, the COADS 2°\nmonthly summary products will need further format refinement before they are\neconomical for routine analysis. The fine space (2° latitude X 2° longitude)\n23","and time (monthly) resolution requires that a special format be perfected.\nThis will be a packed-binary format with special compression of land areas or\nmissing data, designed to present a relatively simple Fortran-user viewpoint\nof the storage details.\nCOADS is the most extensive marine data base now available for studies of\nthe boundary between the ocean and the atmosphere. But problems, limitations,\nand inhomogeneities in the input data have in many cases not been corrected\nand are not yet fully recognized or understood. Examples are the change in\nmeasurement of sea surface temperature from bucket to intake, or diurnal\neffects on air temperature due to insolational heating of the ship's struc-\nture. A last phase of the planned work will study, over a 2-year period, some\nof these problems by using high-quality (ocean station vessel) or high-density\n(heavily traveled ship route) subsets.\nHighly Reflective Clouds\nHighly reflective cloud (HRC) data will continue to be updated for FY\n1985. A comprehensive statistical analysis and evaluation of this data set\nwill appear in the form of a user's guide to the HRC data set, as well as in a\npublished article detailing the quantitative comparison of the HRC and GOES\nPrecipitation Index. Other studies are planned, including an analysis of the\nlong-term variability of tropical convection in both space and time.\nDIAGNOSTIC STUDIES\nENSO Variability\nThe diagnostic work carried out in FY 1984 regarding ENSO classification\nwill continue, and new parameters will be added to the list. Rainfall data\nfrom equatorial Pacific Island stations will be analyzed, as well as the\nchanges in the sea level pressure field in the southwestern and central\nPacific. The spatial and temporal variability of these fields during the ENSO\ncycle will be studied as an aid in ENSO prediction.\nAnalysis of Equatorial Westerly Wind/Convection Episodes (WWCE)\nDuring the 1982-83 ENSO\nAnalysis will continue on the fields of atmospheric moisture and\nstability, organized convection, surface and upper-level winds, and sea\nsurface temperatures at different stages in the evolution of the WWCE's\nassociated with the eastward shift of convection in the equatorial Pacific\nduring the 1982-83 ENSO event. The aim of this research is to establish a\nsynoptic model of the evolution of WWCE's and shed some light on the\nconditions that caused WWCE's to move farther east during the 1982-83 ENSO\nthan in previous ENSO events. The search for possible precursors in the\nSouthern Hemisphere circulation will be continued.\nTropical-Extratropical Teleconnections\nStudies of the linkage between synoptic-scale events in the tropics and\nextratropics will continue and be completed during the second year of the\n24","NSF-funded project. Occurrences of the synoptic sequence during ENSO vs.\nnon-ENSO winters will be compared and contrasted in order to assess the role\nof this atmospheric process in the interannual variability of the climate of\nNorth America. The synoptic interactions associated with the strength of the\ngeneral atmospheric circulation will be examined through diagnostic studies of\nthe fluxes of westerly momentum in connection with tropical convective\noutbreaks and the exchange with the subtropical jet.\nDiagnostic Interpretation of the Ocean Climate Record\nDetailed regional analyses of SST and surface air temperature from COADS,\nas well as of the surface pressure and wind fields will be carried out in\norder to assess the reliability of the data as well as to estimate any\ncorrections to be made. Work will be started to merge the ocean and land\nrecord in order to produce an integrated Northern Hemisphere record.\nAnalysis of Secular Climatic Fluctuations Over the Northern Hemisphere\nThe spatial and temporal variability of climatic change over the oceans\nand continents will be mapped. Emphasis will be placed on determining the\nzonal and meridional differences associated with different climatic regimes.\nENSO Monitoring\nA set of climatic indices of ENSO development, based on statistical\nsummary and analysis of near-real-time data will be produced. The data will\nbe acquired from the Navy and Global Telecommunication System (GTS), by way of\nthe National Meteorological Center, NOAA. Part of the development work for\nthese indices will be to compile a set of verification statistics on each of\nthem separately, and in combination. The aim is to develop a monitoring\nCRP\ncapability as near real-time as possible, in order to alert interested parties\nto the occurrence of anomalous weather conditions in the Pacific and Indian\nOceans that may be precursors to an ENSO episode.\nOther Studies of Climate Variability\nA 3-year proposal to study long-term climatic fluctuations has been\nsubmitted to the U.S. Department of Energy jointly by the University of\nMassachusetts, the University of East Anglia (U.K.) and CRP. Its principal\naim is to study a number of climatological problems related to the carbon\ndioxide question. These include an analysis of areal changes in precipitation\nand precipitation variability, with special attention to the Northern\nHemisphere's grain-growing regions; relationships between precipitation and\ntemperature variations interpreted in terms of atmospheric circulation\nchanges; analysis of high-latitude climatic fluctuations, with a focus on\nsurface and near-surface inversion climatology; and studies of regional\nclimate variations and their relationship to large-scale hemispheric\nfluctuations.\n25","ICE SHEET MODELING\nThe mass-balance descriptions of the Antarctica ice sheet will be\nextended to cover the whole of West Antarctica and some of the major drainage\nbasins of East Antarctica. Improved parameterizations of basal sliding will\nbe developed around models of basal drainage, taking into account new data for\nColumbia and Variegated Glaciers. A new model describing the dynamics and\nthermodynamics of a free-floating ice shelf will be programmed and tested.\nWEATHER RESEARCH PROGRAM\nThe Weather Research Program (WRP) conducts research related to weather\nobservation and prediction to increase the understanding of, and to improve\nprediction of, mesoscale weather systems. The genesis, evolution, and\nstructure of convectively driven systems constitute the primary emphases of\ncurrent WRP research. Attention is focused principally on moist convection\nover the United States; clouds ranging from individual thunderstorms to large\nmesoscale precipitation systems are under investigation. An important\nemphasis is on the transfer of results and potential techniques for predicting\nconvection to the National Weather Service (NWS) and the national user\ncommunity. Another major emphasis is on employing the NOAA research aircraft\nin mesoscale studies. Not only does WRP research contribute to long-range\nprogress in furthering understanding of convective weather systems, but\nstudies are also made that can be expected to have an early impact on\nforecasting of convection.\nThe three groups in WRP, Mesoscale Applications Group (MAG), Mesoscale\nResearch Group (MRG), and Mesoscale Studies Group (MSG), all conduct applied\nand basic research on the following general subjects:\nInteractions between mesoscale processes, and both synoptic-scale\ncirculations and cloud-scale processes as revealed by dynamical and\nthermodynamical analyses.\nThe uses to which new remote-sensor data streams can be put to improve\nunderstanding and prediction of convectively driven weather systems.\nThe spatial and temporal variations in convective and stratiform\nprecipitation during the life cycle of mesoscale convective systems.\nAccomplishments FY 1984\nA 1-month project, called Airborne Investigations of Mesoscale Convective\nSystems (AIMCS) was conducted from 18 June to 18 July 1984 using the NOAA P-3\naircraft based in Denver. This project was designed to investigate large,\nslow-moving nocturnal mesoscale convective systems (MCS's) that develop over\nthe High Plains. Convective systems of varying sizes were investigated and\nprobed during the program. The goals were to collect data to investigate the\ninternal structure of MCS's (particularly in the form of airborne Doppler\nradar), and to evaluate aircraft capabilities and the feasibility of flying\nsuch systems. Through the cooperation of the NWS, additional soundings were\n26","taken on several nights at a number of NWS upper-air stations. In addition,\nthe Regional And Mesoscale Meteorology (RAMM) Branch of NESDIS in Fort Collins\ncollected special satellite data during the AIMCS program. An operational\nsummary of this project is being prepared.\nA five-year climatology of MCS's was completed and included in STORM\n(Storm-scale Operational and Research Meteorology) planning documents. Maps\nand other statistics were completed for 15-day periods for MCC's (Mesoscale\nConvective Complexes), beta- and alpha-scale cloud clusters, and convective\nlines. In addition, the ability to quickly diagnose infrared temperature\ncharacteristics of MCS's was automated using satellite data available from\nPROFS.\nTwo NWS Southern Region forecasters spent 4-month periods at WRP during\nFY 1984. They were here to pursue applied research activities related to\nmesoscale weather forecasting and analysis problems of significance to the\nSouthern Region. These visits, made without their normal shift\nresponsibilities and in coordination with researchers with longer-term goals\nof a similar nature, provided a unique opportunity to accomplish work that\ncould not have been done effectively on station.\nThe climatology of cloud-to-ground lightning in north-central Colorado\nwas developed for the summer of 1983. The study shows substantial agreement\nwith a previous study of radar echo frequency in this region. Diurnal curves\nof lightning frequency were developed at NWS stations and at several mountain\npeaks and cities in this area. This study shows the advantage of lightning\ndata in making large climatological studies with much less difficulty than\nwith radar reflectivities. Furthermore, the data are much less complex to\ninterpret and they identify the thunderstorms of interest to many users.\nResearch with data from the Kennedy Space Center (KSC) has been designed\nto improve forecasting of convection and associated lightning under light flow\nregimes in the summer. One study has been the development of a climatology of\ncloud-to-cloud lightning over the region surrounding KSC for the summer of\nWRP\n1983, including average diurnal curves at selected cities in the area.\nAnother study used case days in the summer of 1983 to show how cloud-to-ground\nlightning relates to divergence and radar reflectivity in the KSC region, and\nhow the information can be used in short-term thunderstorm forecasting at that\nfacility.\nA synoptic climatological study of importance to the Denver area was\nbegun, in conjunction with staff of the Denver NWS forecast office, to examine\nconditions that produce blizzards and heavy snowfalls. In addition to having\ncostly societal impacts along the populous Front Range, these storms are\nusually characterized by pronounced mesoscale variations in snow accumulation\nover eastern Colorado. Snowstorms of significance in the last 10 years are\nbeing examined for recurrent synoptic flows with the eventual intent of\nimproving NWS forecasts of these critical storms. This project developed from\na 3-month tour of duty to the Denver NWS office (as a shift forecaster) by a\nWRP staff member.\nIntegrated water vapor from the Denver profiler for the summers of 1982\nand 1983 are being analyzed for diurnal variations. Vapor was found to\ndecrease from 1800 MST through the nighttime hours to 1000 MST, then increase\nto 1800 MST on more than half the days. Results compared very well with\n27","radiosonde-measured integrated water vapor. This diurnal pattern seems\nconsistent with a mountain-plains daily circulation in the Denver area;\nhowever, several possible causative mechanisms are being considered.\nThe characteristics of dual MCC's that occurred on the night of 19-20 May\n1979, as well as an MCS that traversed the SESAME area on 20 May 1979, were\nstudied extensively with radar, mesonetwork, and upper-air data that have not\nbeen previously available in detail for such systems. The ratio of convective\nto stratiform precipitation, the internal circulations, environmental flows,\nand other features have been the main topics of investigation. Several\nresults of these unique case studies had impacts on the operational strategies\nemployed in the AIMCS program.\nResearch began into the nature of wind-field interpolation techniques\nbased on the mathematical theory of vector point functions. It is increasingly\nclear that treating wind components as independent scalars for interpolation\nprecludes proper diagnosis of the wind field, especially with respect to the\nall-important derivatives (i.e., divergence, vorticity, and deformation).\nMethods for dealing with this problem are being explored with a view toward\ndeveloping practical and accurate algorithms as alternatives to current widely\nused approaches.\nPatterns in the large-scale flow field conducive to MCC development have\nbegun to be examined. As a first look at this massive data set, the 500-mb\nchart taken before the maximum extent of each MCC was examined and classified\nas to type of synoptic pattern. A large majority of the systems occurred with\na quasi-stationary long-wave trough over the western United States and a flat\nridge over the central states; MCC's developed within or just upwind from the\nridge axis with westerly flow.\nA technique using omega (vertical motion) diagnostics based on quasi-\ngeostrophic theory of mass-momentum adjustments has been employed in several\ncase studies. A strong correlation between the adjustment fields and the type\nof convective activity has become apparent. Also, significant departures from\nLFM (Limited Fine-Mesh) 700-mb vertical motion forecasts have been found.\nExperimental real-time computations of the Q-vector field during AIMCS were\nconsidered to be a useful supplement to other methods for analyzing areas of\npotential MCC development.\nA new version of the Fritsch-Chappell parameterization code provided by\nscientists at Pennsylvania State University was incorporated into the two-\ndimensional WRP hydrostatic model, and simulations of idealized mesoscale\nconvective systems were carried out. The 10-15 hour simulations successfully\nproduces warming in the upper troposphere and associated large mesoscale\ncirculation driven by the parameterized convective heating. However, the\nmodel failed to develop a convectively driven mesohigh near the surface.\nFurther analysis has led to the conclusion that adequate simulation of the\nconvectively driven mesohigh will require six to eight computational levels in\nthe bottom 2 km of the hydrostatic model.\nThe treatment of the top boundary condition in fine-mesh mesoscale models\nis also under investigation. Preliminary indications point to the need for a\nboundary condition other than the one traditionally used in which the vertical\nmotion vanishes at the top of the model, if model simulations are not to be\ncontaminated by spurious downward reflection of gravity waves.\n28","WRP staff taught at all five flash flood courses at the NWS Training\nCenter in Kansas City during FY 1984, and also developed a series of teaching\naids in response to student comments.\nThe preferred synoptic conditions under which dry microbursts occur have\nbeen identified using JAWS (Joint Airport Weather Studies) data from Denver in\n1982, as well as from situations that resulted in recent aircraft accidents in\nthe western states. Conditions that provide a favorable microburst environment\nconsist of significant moisture (dew point depression of 6°C or less) near 500\nmb. This moist layer fuels high-bases convection, which in conjunction with a\nnearly dry-adiabatic lapse rate from 700 to 500 mb, can produce localized,\nvery strong downdrafts hazardous to aircraft takeoffs and landings. During\nthe convective season, maps at 1200 GMT sometimes show large portions of the\nWest to be covered by potentially favorable conditions for dry microbursts on\nthat day.\nRainfall was estimated from satellite data for August 1979 over the\ncentral third of the United States in order to compare satellite-derived\nprecipitation values with daily area-averaged rainfall from gauges in that\nregion. On the average the unadjusted versions of the satellite techniques\noverestimated the rain when compared with the gauges, and the environmentally\nadjusted satellite rainfalls exceeded the gauge rainfalls by a factor of 2.0,\nbut after adjustment the satellite rainfalls were 20% smaller than the gauge\nrainfalls; correlations for these rainfalls ranged from 0.6 to 0.7. On an\nhourly basis, the unadjusted satellite data overestimated by a factor of 2.2,\nthe adjusted satellite rainfalls being 10% smaller than the gauge values.\nCorrelation coefficients dropped to the range 0.5-0.6.\nSituations in which significant severe weather outbreaks occurred within\nlarge-scale settings that were not typical of outbreak days were examined in\ntwo case studies by WRP in FY 1984, and a third early morning case study was\nstarted. These events represent a challenge to the longer term thunderstorm\nforecast system since they are not controlled by the evolution and movement of\nintense baroclinic weather systems.\nWRP\nA case study was begun of the Denver hailstorm of 13 June 1984, which\ncaused the most devastating weather-related loss in the city's history in\nterms of insurance costs. Both standard and special data are being studied to\ndocument some of the features of this storm.\nAs the STORM-Central project's plans developed through FY 1984, WRP staff\nmade major contributions on the NOAA level in meetings, documents, and\ninteractions with agencies in project design, scientific goals, and research\nleading to the field program scheduled in the late 1980's.\nPlans FY 1985\nA project called 0-K PRE-STORM (Oklahoma-Kansas Preliminary Regional\nExperiment for STORM-Central) is planned to take place during May and June\n1985. In cooperation with scientists from NSSL, the Hurricane Research\nDivision of AOML, NCAR, and university groups, WRP will investigate MCS's from\na base of operations in Oklahoma City. Both NOAA P-3 aircraft will be\ninvolved in the program, as well as special surface and upper-air networks,\n29","additional ground-based Doppler radars, lightning detectors, and possibly\nprofilers. Goals of the program are to investigate the evolution and\nstructure of MCS's, and to test observational and operational strategies for\nthe STORM-Central program's field phase.\nAnalyses of data collected during the AIMCS program in 1984 will proceed\nwith a view toward improving forecasts and operations strategy in the 1985 O-K\nPRE-STORM program, and toward better understanding of the evolution and\nstructure of MCS's that were observed during the program. Studies will use\ndata from the P-3 platform, particularly from the Doppler radar, as well as\nupper-air soundings, ground-based conventional data, and special satellite\ninformation.\nThe climatology of 1983 MCC's will be completed and submitted for formal\njournal publication, and data for the 1984 summary will be compiled. During\nFY 1985, the automated analysis of infrared temperatures will be tested to\ncomplete this documentation more rapidly and objectively than in the past.\nThis climatological data base will be used in a variety of research activities\nat WRP and elsewhere, especially in a detailed evaluation of several\nexploratory forecast efforts in an attempt to learn ways to improve NOAA field\nservices.\nCloud-to-ground lightning data gathered over north-central Colorado will\nbe stratified for the summer months to define the synoptic-scale conditions\nunder which large numbers of flashes occur, compared with low-lightning days.\nIn addition, the diurnal changes in the distribution of flashes over\nmountains and plains accompanying specific large-scale conditions will be\nanalyzed for possible application to thunderstorm and lightning forecasting in\nmountainous areas.\nClimatologies of lightning similar to the Colorado climatology will be\ndeveloped for the Kennedy Space Center area in summer months for comparing\nchanges in land-sea diurnal changes as a function of synoptic controls. The\nrelations between radar echoes and lightning will be explored in order to\nidentify better the types of reflectivity patterns producing cloud-to-ground\nflashes.\nThe snowstorm study for Colorado will continue to define the large-scale\nconditions under which heavy snowfall occurs at Denver, with a view toward\nreal-time testing of the procedures during the winter at the Denver NWS.\nFurther work, based on the results of the real-time testing, will define the\npattern recognition techniques for applications during the winters of 1985/86;\nin addition, the study will be expanded to include heavy snow events that were\nconfined to other population centers along the Front Range.\nThe strong diurnal cycle found in the Denver profiler water vapor data\nwill be studied by considering the relations of winds and large-scale\nmeteorological regimes to daily variations. Profiler wind data from northeast\nColorado will also be examined for evidence of migratory short waves that may\nhave been associated with the MCS's flown during AIMCS.\nAnalysis of the SESAME case study day of 20 May 1979 will be completed\nduring FY 1985 in order to document as completely as possible the structure,\ndynamics, and interactions of a slow-moving nocturnal MCS.\n30","Wind-field interpolation techniques and prognostic/diagnostic routines of\ndirect utility in operational weather forecasting will be examined from a\nvariety of perspectives, using such tools as desk-top microcomputers. The\nresults are expected to affect both operational meteorology and research\nactivities during FY 1985 through publications, talks, and demonstrations to\nNWS staff, and use in forecaster training courses and workshops.\nParameters used in forecasting convective weather systems, especially LFM\ngrid-point data, will be studied using AIMCS 1984 forecasts and experimental\nforecasts made during two summers in coordination with other, operational NOAA\nagencies. Additional work will concentrate on LFM performance in past cases\nto establish relationships between predicted variables and occurrence of\nMCS's.\nA major reformulation of the Fritsch-Chappell parameterization scheme\ndesigned to remove all physical inconsistencies will be completed and tested\nin the WRP two-dimensional model. Collaboration with scientists at NMC will\nbe undertaken to begin testing the scheme on real data cases using an\noperational model. Work will continue on other aspects of the interaction of\nconvection with its mesoscale and larger scale environment.\nInteractions with NWS will continue in FY 1985 through such activities as\nformal forecaster training courses on flash floods and mesoscale forecasting\ngiven by WRP staff at the NWS Training Center, workshops and seminars at NWS\nfacilities, exchange of staff for extended periods, cooperative applied\nresearch activities, and participation in the planning process for\nExperimental Forecast Centers as part of STORM-Central.\nSynoptic environments of the dry microburst in western states will be\nevaluated for 1982 and 1984 in Colorado on both daily and monthly scales. In\naddition, studies will focus on the synoptic settings in which wet microbursts\noccurred in the JAWS area and have caused aircraft crashes in recent years in\nareas with high moisture.\nSatellite-derived rain estimates will be made with the ERL technique for\nPROFS\nselected AIMCS cases with the objective of determining whether the\ntransformation of the system from convective to stratiform rainfall can be\nrecognized by the satellite.\nThe Denver hailstorm study will examine the data for 13 June 1984, when\nunique photographs and PROFS mesonetwork information and other, nonstandard\ninformation can be used to specify some of the conditions that produced a\nconvective event with such devastating results.\nPROGRAM FOR REGIONAL OBSERVING AND\nFORECASTING SERVICES\nThe mission of the Program for Regional Observing and Forecasting\nServices (PROFS) is to improve operational weather services by testing and\ntransferring advances in research and technology. PROFS, using the results of\nERL basic research, develops operationally feasible forecast techniques that\nincorporate available observations, computer processing, and human\ninteraction. PROFS integrates capabilities into specific systems, then tests\nand evaluates those systems in forecasting exercises. The evaluation results,\n31","both quantitative and qualitative, are translated into recommendations for the\ndirection of research and operational activities.\nPROFS works closely with the weather research community--for example,\nother ERL groups and the National Center for Atmospheric Research (NCAR) --\nsoliciting their ideas on forecasting workstations and consulting them on\nplans for test exercises. PROFS also works with the three major operational\nservices: the National Weather Service (NWS), the Federal Aviation\nAdministration (FAA), and the U.S. Air Force's Air Weather Service (AWS).\nTwo NWS employees are members of PROFS' senior staff, and a third will\njoin in FY 1985 to coordinate work on NWS's Advanced Weather Interactive\nProcessing System for the 1990's (AWIPS-90) to be done by PROFS. For the FAA,\nPROFS has installed an advanced workstation at the Denver Air Route Traffic\nControl Center (ARTCC). For NEXRAD (Next Generation Weather Radar), a joint\nprogram of NWS, FAA, and the Air Force, PROFS has coded and tested algorithms\nthat will become part of the new national radar system.\nPROFS has worked with groups from abroad as well. For example, Saudi\nArabia is seeking advice on a national meteorological system, the Australian\nMeteorological Bureau and PROFS have exchanged consultants, and a group from the\nSwedish Meteorological and Hydrological Institute will visit in early FY 1985.\nBecause of PROFS' innovative nature, visitors from Federal agencies,\nuniversities, private industry, and foreign countries continually tour the\nPROFS facilities for information and demonstrations The Visitor Coordinator\nplans about 100 visits each month.\nEXPLORATORY DEVELOPMENT FACILITY\nThe Facility Branch is responsible for the design, development, upgrade,\noperation, and maintenance of the PROFS Exploratory Development Facility\n(EDF). The EDF consists of the computers, data ingest interfaces,\ncommunication links, and display devices that allow the testing and evaluation\nof advanced weather information systems. It has been undergoing continual\nupgrades and changes since the beginning of PROFS. The system acquires and\nstores a large variety of meteorological data, analyzes and processes the data\ninto products, and displays the products to forecasters using an interactive\nworkstation.\nAccomplishments FY 1984\nIn 1984, several new data interfaces were developed and others signifi-\ncantly upgraded. A SATCOM III (RCA Satellite Communications) satellite\nreceiver was installed, a PDP-11/24 computer hardware interface was assembled,\nand the necessary software was written to acquire Limited-area Fine Mesh (LFM)\nmodel data from the National Meteorological Center (NMC). The Profiler ingest\nsoftware was expanded to handle three additional sites (Lay Creek, Cahone, and\nFleming, Colo.) in addition to Platteville and Denver. A substantially\nexpanded Surface Aviation Observations (SAO) data set covering the entire\nUnited States was acquired through the AFOS (Automation of Field Operations\nand Services) connection in place of the earlier FAA 604 line. The reliability\n32","of the two conventional radar interfaces was enhanced significantly by estab-\nlishment of a dial-in capability for the PDP-11/23 computers at the remote\nradar sites. Also, the ability to down-line load the radar interface\noperating software from Boulder, in case of power failures, was developed.\nCareful monitoring of the mesonet data revealed several sensor problems that\nwere subsequently corrected, thus measurably improving the data quality.\nThe overall efficiency of the PROFS computer network was substantially\nenhanced by interconnecting the processors with Ethernet, a 10-Mbps (10 million\nbits per second) local-area network. Ethernet increased the speed of data\ntransfers among the computers by an order of magnitude and allowed more\nefficient sharing of terminal, printer, and mass-storage resources.\nAdditional enhancements were obtained by upgrading all PDP computers to\nVersion 4.1 of the RSX operating system and updating all nodes of the computer\ncommunications network to DECnet Phase IV.\nIn November 1983, in conjunction with the Interactive Meteorological\nProcessing Conference held at NASA Goddard Space Flight Center in Greenbelt,\nMd., a fully functional PROFS workstation was assembled and demonstrated with\narchived data. Conference visitors expressed great interest in the rich variety\nof available data displays and the ease of operating the workstation.\nIn support of the Ocean Service Center (OSC) project of the National Ocean\nService, a study was made to explore the applicability of PROFS techniques for\nOSC. The final report included a top-level system analysis and recommended\nsystem architecture for implementation.\nA real-time workstation, connected to the PROFS EDF through a 56-kbps\n(56,000 bits per second) telephone link, was developed and deployed at the FAA\nARTCC in Longmont, Colo., in June 1984. NWS forecasters at the ARTCC have\nfound the workstation most valuable in advising the FAA controllers about\nweather conditions in the Colorado Front Range. In several documented cases,\nthe PROFS data allowed controllers to make important re-routing decisions more\naccurately and faster, thus improving overall air safety.\nPROFS\nThroughout the year, the Facility Branch continued to supply real-time\nmesonet, Profiler, and/or Limon radar data to the NWS Denver Forecast Office,\nU.S. Department of Energy's Rocky Flats operations, Colorado State University\nin Fort Collins, Solar Energy Research Institute in Golden, and the ERL Wave\nPropagation and Aeronomy Laboratories. In addition, approximately 75 requests\nfor archived data were serviced.\nPlans FY 1985\nUpgrade the EDF computer network with the high-speed (70 Mbps) VAXcluster\ninterconnect to allow rapid transfer of large blocks of data among\nprocessors and more efficient use of mass storage devices.\nReconfigure the facility to support the real-time 1985 exercise and\nseveral projects: Central Weather Processor (CWP), Ocean Service Center,\nAWIPS-90, PROVAS (Profiler-VAS), and others.\n33","in cases where either the desired information requires an interaction with the\nuser or where the resulting display product is one that is seldom used.\nDuring PROFS' real-time exercise in the summer of 1983, forecasters were\nforced to be content with only the scheduled products. Early in FY 1984 the\nfirst application programs were installed. The Applications team worked with\nthe original authors of the programs, adding workstation-specific code, to\nproduce some dozen programs for use during the 1984 cool-season exercise. The\nfunction of these programs ranges from simple information about where a\nthunderstorm is occurring in geographical terms to complex combinations of\nimages from different sensors, e.g., radar reflectivity combined with visible\nsatellite data.\nThese programs and others have been refined and thoroughly tested, and\nhave been included in the workstation that PROFS has installed at the ARTCC in\nLongmont, Colo. Members of the Applications team are responsible for\nmaintaining and enhancing the programs in support of the operational use of\nthat workstation.\nThe VAS Applications team, in cooperation with NESDIS (National\nEnvironmental Satellite, Data, and Information Service) and the NOAA Operational\nVAS Assessment (NOVA), has upgraded the PROFS satellite data processing\ncapabilities. Of specific interest are the addition of eal-time VISSR\n(Visible and Infrared Spin Scan Radiometer) Atmospheric Sounder (VAS) data to\nthe state-of-the-art workstation and the utility of the data as a mesoscale\nobservation and forecasting tool. VAS data are available from the newer\ngeosynchronous satellites (since GOES-4), which offer infrared data for 12\ndifferent spectral bands capable of a variety of uses. The VAS Applications\nteam put together a new data base for archiving VAS multi-spectral imagery\n(MSI) and dwell sounding data, and wrote the first VAS MSI product software\nfor the workstation. When the data base is complete, PROFS will routinely\nproduce VAS upper-level water vapor imagery, VAS \"split window\" low-level\nwater vapor imagery, and a stability image (a numerical combination of the two\nformer images). In addition, the team has developed a data base to store\nprocessed VAS sounding retrievals to be used for workstation products and the\nmesoscale analysis package in the coming year.\nThe FAA is developing a Central Weather Processor (CWP), an electronic\nprocessor workstation and disseminator, for use by its meteorologists in the\nCenter Weather Service Units (CWSU) at all ARTCC's PROFS' role in CWP\ndevelopment is to identify and transfer the most suitable techniques for\ninteractively describing, processing, and displaying meteorological data and\nanalyses. The results of these analyses, tailored to air traffic control needs,\nwill be graphics and text descriptions of icing, clear air turbulence,\nthunderstorms, low ceilings and visibilities, cloud tops, precipitation, and\nwinds aloft. The PROFS CWP team has prepared a 3-year plan for meteorological\napplications development and demonstration. The plan and its resulting\nmeteorological products rely heavily on the PROFS Mesoscale Analysis and\nPrediction System (MAPS) as the framework for data analysis. Already clear air\nturbulence and icing applications are under development.\nThe Analysis and Prediction team is currently in the midst of a long-term\neffort to develop MAPS. The goal is a robust, portable, multipurpose software\nsystem for objective analysis of mesoscale weather systems and for interactive\n34","Upgrade and expand the EDF data acquisition capabilities: establish an\ninterface to the new NMC Domestic Data Service; switch over the lightning\ndata acquisition to the new Lightning Location and Protection, Inc.,\nnetwork; and upgrade the Profiler data ingest subsystem.\nContinue the distribution of real-time and archived data to research\nand operational users.\nEXPLORATORY DEVELOPMENT GROUP\nDuring FY 1984, Advanced Data Systems merged with the Exploratory\nDevelopment Group (EDG), which now comprises two branches: Science and\nTechnology. The former produces software for the meteorological workstation,\ndeveloping products and applications that forecasters can use to assess the\ncurrent state and near-term future of the atmosphere, with emphasis on the\nlocal area. The latter selects promising technologies such as Doppler radar\nand satellites, and tailors them for use in a weather forecasting workstation.\nAccomplishments FY 1984\nSCIENCE BRANCH\nThe Meteorological Products team is responsible for the scheduler-generated\ndata displays, or products, used in the PROFS workstation. These include most\nradar and satellite imagery, as well as graphic displays such as plots of\nmesonet and SAO data. Since this team was formed in October 1983, it has\ndeveloped the following:\nAn algorithm to draw range/elevation circles, given antenna elevation, as\nbackground to radar PPI's (plan position indicators).\nAn effective display for the NOAA/WPL thermodynamic Profiler. In a\nPROFS\nsingle graphic, this product includes a 4-h time series of temperature\nprofile change, potential temperature time/height \"surfaces,\" and\nprecipitable-water time series.\nAn improved display of Profiler wind, time/height cross sections.\nIndependent algorithms for isentropic cross section analysis.\nThe Meteorological Products team also planned and ran PROFS' first\ncool-season forecast experiment, from February to April. The objective was to\nlearn how the PROFS system would work in forecasts of long-duration winter\nstorms rather than short-lived convective events.\nThe Meteorology Applications team develops interactive and on-demand\nprograms for the PROFS advanced forecaster workstation. Most displays of\nweather data, whether they be images, data plots, or vector graphics, are\nproduced on a scheduled basis, and are thus available for nearly instant recall\nby forecasters at the workstation. Applications, on the other hand, are used\n35","manipulation of observation, analysis, and prediction products. Ultimately,\nMAPS will support many users with diverse needs, both inside and outside PROFS.\nThe team is developing MAPS by iteratively refining prototype systems\nrather than by completely pre-specifying all software modules. At least three\nrealizations of the system are currently planned. In FY 1984 the team has\nworked principally on the system realization that will support the 1985\nreal-time exercise. Beyond 1985 the system will incorporate a quasi-\ngeostrophic prediction model, a surface analysis, and possibly a change of\nvertical coordinate from pressure to potential temperature.\nTECHNOLOGY BRANCH\nThe Radar team completed a major upgrade to radar data ingest capabili-\nties, adding full-resolution Doppler data, production of images, and NEXRAD\nalgorithm products in real time to the PROFS workstation. Six NEXRAD\nalgorithms are now in real-time operation. The communication bandwidth\nbetween the NCAR CP-2 radar and the PROFS EDF has been increased through the\nuse of a microwave radio link with typical bit error rates less than 1 in\n1012\nThe NEXRAD team continued work with the NEXRAD Joint System Program Office\nby coding and assessing algorithms and by providing test data sets. Eight\nalgorithms were coded and run on real Doppler data to ascertain whether\nFORTRAN code could be written directly from the NEXRAD algorithm descriptions.\nAdditional assessments of these eight algorithms included resolution\nsensitivity and parameter sensitivity studies. Other accomplishments were the\ncoding and testing of three more algorithms, development of a synthetic data\nset, delivery of a set of documented Doppler data from the NCAR CP-2 radar,\nand acquisition of additional CP-2 Doppler data from interesting severe\nconvective storms.\nPROFS upgraded its GOES groundstation hardware and software to enhance\nthe system's capabilities, streamline the design for reliability and easier\nmaintenance, and produce system documentation. Several hardware changes were\nmade to the frame synchronizer and sectorizer. A Mode AAA operational VAS\ncapability was added in anticipation of NESDIS's switch to this new trans-\nmission mode in mid-1986. Bit-error-rate detection was added to improve\nquality control. The sectorizer was modified to perform exact sectorizing.\nSoftware changes were required to accommodate the changes in hardware and to\nprovide new Mode AA research VAS data formats. One major effort was a new\ndevice driver for the frame synchronizer and sectorizer. To centralize\nsatellite ingest and to achieve more distributed processing from a larger\nsystem point of view, more ingest and preprocessing tasks are now performed on\nthe satellite subsystem.\nPROVAS (PROfiler-VAS) is the system being developed jointly by PROFS and\nWPL, which takes data from the Profiler and the VAS and produces an estimate\nof the vertical profiles of atmospheric temperature and water vapor. These\nprofiles from the combined data have less error than those produced by each\nsystem separately. During FY 1984 the PROVAS system was initiated, designed,\nand built to professional documentation and design standards for use during\nyearly PROFS exercises.\n36","The video disk is one component of an advanced training method that\ncombines computer-based instruction (CBI) and the PROFS data sets. That\nmethod is the centerpiece of a proposed national program that will continually\ntrain meteorologists from universities, research facilities, and NWS forecast\ncenters in advanced forecast techniques and meteorological understanding.\nDevelopment of the first instructional video disk began in January 1984 when\nthe Interactive Meteorological Educational and Training System (IMETS) project\nwas formed. The project's first task was to analyze and catalog data from the\nreal-time exercise in summer 1983. Selected cases from the data will be put\nonto a video disk for use in CBI courses at a proposed training center for\nmeteorologists. A forecast workstation was installed at PROFS, and a CBI\ndemonstration package was developed that uses a prototype video disk and a\nmicrocomputer. In addition to specific technical accomplishments, the project\nhas submitted a proposal to the National Science Foundation for funds to\nestablish a national training center at St. Louis University. The center will\nserve research staff and students from the university, and operational\nforecasters from NWS and AWS.\nPlans FY 1985\nSCIENCE BRANCH\nIn August 1984, real-time ingest of gridded LFM data was added to the PROFS\nfacility. The Meteorological Products team can now begin work suggested by\nother NOAA researchers, i.e., recontouring the LFM model output to reveal\nfiner structure in the numerical data than can be seen in the output from NMC\ngraphic products. Forecasters will be able to interactively select the\ncontour interval for any of several analyzed and forecast field variables.\nThe team will also write a report summarizing the product usage patterns of\nforecasters during the 1983 summer forecast experiment. Every product display\ncommand entered during the experiment was logged for later analysis; the team\nwill determine which information forecasters find most useful when issuing\nwarnings and routine forecasts.\nPROFS\nDuring FY 1985, the Applications team will concentrate on two activities,\nboth in support of the real-time exercise planned for the summer of 1985.\nFirst, write new applications programs. There is a substantial list of\ndesired programs from past experience, and many requests from forecasters\nare expected in the months to come. Forecaster training sessions are\nscheduled to go on during the winter, and many suggestions will probably\nbe offered by the trainees.\nSecond, upgrade existing programs. Since a new version of the\nworkstation software will be forthcoming, some changes will be required\nsimply to maintain the programs in working order. In addition, a more\ncoherent structure to the applications as a whole is needed to simplify\nthe task of the forecaster. Logically associated programs should be\npresented to the forecaster as such, thus allowing essential information\nto be accessed more rapidly.\nThe plans for VAS application development at PROFS are as follows:\n37","To establish a data base capable of performing the I/O (input/output)\nrequirements to support routine VAS product generation. This encompasses\na new VAS file format and the new software for the I/O function.\nTo develop three initial VAS image products for use at the workstation:\n(1) Low-level water vapor image derived from two VAS bands, highlighting\nthe areas of water vapor in the surface-to-700-mbar layer.\n(2) Upper-level water vapor image from a single VAS band, showing the water\nvapor distribution in the 700-mbar-to-tropopause layer.\n(3) A composite of 1 and 2 to determine the areas of instability.\nThe CWP team will develop and demonstrate preliminary meteorological\napplications for clear air turbulence, icing, winds, thunderstorms,\nprecipitation, low ceilings and visibilities, and cloud tops. These\napplications, using both automated algorithms and meteorologist interactions,\nwill be demonstrated to CWSU field meteorologists. Results of the demonstra-\ntions will be fed back into the applications work to improve performance and\nusefulness.\nTECHNOLOGY BRANCH\nThe Radar team will streamline the real-time design to improve\nperformance and ready the subsystem for the 1985 experiment. Major new work\nincludes the workstation radar interface and possibly a high-speed image\ngenerator. This new radar subsystem will allow PROFS to address the NEXRAD\nAWIPS-90 interface questions.\nWork with NEXRAD will include continued assessment of the algorithm\ndescriptions, further parameter and resolution sensitivity studies, coding of\nadditional algorithms, preparation of a data set containing both real and\nsynthetic Doppler data, and displaced real-time product assessment.\nThe PROVAS system has been designed to allow the testing of various\ncombinations of algorithms. Its flexibility will allow testing of recently\nproposed techniques, for example, inferring the vertical location of temperature\ngradient changes by means of the radar return power. Such vertical locations\ncan then be used as a boundary condition on the retrieved temperature profile.\nThe IMETS project will concentrate on three activities in FY 1985:\nSecure funds to open and operate a video disk teaching center at St.\nLouis University and begin construction of the center by September 1985.\nDevelop another PROFS video disk.\nDevelop teaching material to complement the video disks.\n38","SYSTEM ANALYSIS AND DESIGN\nThe System Analysis and Design Branch (SA&D) is responsible for\nspecifying the system software and hardware architecture that best suits a\nparticular project's needs. 'In most instances only some of PROFS' computer\nresources are available to any particular project, and resources may be shared\nwith other activities. To establish resource requirements, SA&D typically\nperforms functional analyses of project requirements, measures computer\nresource requirements of similar software, and performs, where feasible,\nsystem load simulations to evaluate resource utilization.\nSA&D also performs software development relative to system control\nfunctions, such as the workstation executive, user interface, and the product\nscheduler. Before a system realization (configuration) becomes functional, SA&D\nintegrates software and performs a system shakedown to detect software errors,\nperforms load leveling, and verifies system response.\nAccomplishments FY 1984\nSince the PROFS real-time exercise in late FY 1983, SA&D has helped develop\nand integrate five system realizations:\nMERIT (Minimum Energy Routes using Interactive Techniques)- A NASA\nproject to provide an interactive system for defining the minimum energy\nconsumption route for aircraft.\nCool-season exercise--An internal project to apply PROFS system\ncapabilities to analyzing and forecasting winter weather.\nRADRES (Radar Resolution Study) - An internal project to evaluate\nperformance of forecasters using different spatial resolution radar data.\nARTCC--An implementation of a PROFS workstation in an FAA operational\nPROFS\nenvironment for purposes of evaluation.\n'84 Weather Watch--A system realization similar to the ARTCC configuration\nthat allows real-time monitoring of the weather at PROFS.\nSA&D had prime responsibility for the U.S. Air Force's Automated Weather\nDistribution System Driver project and the FAA-sponsored Aviation Route Forecast\nproject. In both cases the objective of the initial phase was to develop\nfunctional requirements, specify external interfaces, and perform a detailed\nfunctional analysis using the dataflow technique. The resulting documents were\naccompanied by detailed task breakdowns, schedules, and personnel resource\nrequirements. The documents were suitable for specifying subsequent system\ndevelopment.\nPlans FY 1985\nPlanned activities are significant enhancements of generic workstation\ncapabilities such as dual display screens and improved user interface,\n39","integration of several new data sources, and the addition of considerably more\nproducts such as the NEXRAD algorithms, PROVAS, and mesoscale analysis and pre-\ndiction outputs. The workstation will be modified to incorporate additional\nAFOS functions, such as text preparation, dissemination, external requests for\ndata, and alerting, and to provide greater flexibility in procedure\ndevelopment. The 1985 system will have most of the functionality of the\nsystem to be installed at the Denver Weather Service Forecast Office in 1986.\nUnder way is a study of data base management systems to characterize the\nPROFS data base and its utilization, to evaluate commercially available\ncandidate data bases, and to recommend a path of action to handle present and\nanticipated data base management needs.\nAnother activity under way is development of a plan for a civilian\nmeteorological processing system for Saudi Arabia. This activity is being\nperformed through and in cooperation with the Office of the Federal\nCoordinator. The present plan is to develop a model facility for the system\nto be installed in Saudi Arabia.\nTEST AND EVALUATION\nTest and Evaluation (T&E) designs and implements nowcasting and\nforecasting experiments; evaluates forecast results and nowcasting\nimprovements by use of objective, quantitative analysis techniques; and\nprepares articles and reports for NOAA management and the open literature.\nAccomplishments FY 1984\nThe major activities of the Test and Evaluation staff were analyzing and\nreporting results of the PROFS 1983 forecasting exercise. Improved accuracy\nin severe weather warning scores was obtained during the exercise. A detailed\nevaluation of precipitation probability forecasts has shown forecaster skill\nrelative to conditional climatology for convective storm situations and has\nsuggested yet further improvement in skill is likely in the future. A summary\nof conditional and sample climatological probabilities of precipitation during\nthe Colorado convective season (May through August) has been prepared as a\nuseful aid to weather forecasters.\nLate in FY 1983, NWS and PROFS conducted a joint analysis of a digital\nradar hail detection algorithm system known as RADAP (Radar Data Processor).\nSignificant improvement in warning scores was demonstrated by use of the\nalgorithm alone; yet further improvements were obtained by experienced\nforecasters using the algorithm output as guidance.\nT&E designed and conducted a test to study the effects of spatial\nresolution of Doppler radar data on severe weather warning operations in April\n1984. The results of this test suggest that the AWIPS-90 system should include\nsufficient bandwidth and central processing capacity to ingest and process\nDoppler radar data obtained from NEXRAD's planned radar data acquisition\nsystem.\n40","It was frequently demonstrated during the 1983 forecast exercise that\ntemperature and humidity profiles obtained from passive radiometry smooth out\nvertical structure (inversions, dry layers) to the extent that the profiles\nare inadequate for short-term analysis and forecasting of severe weather. The\nT&E staff, in a joint effort with WPL, has undertaken a broad program to\ninvestigate possible methods to improve the accuracy and height resolution of\nthe\nradiometry sensor system. Detailed analyses of 5,000 rawinsonde ascents\nfrom the NASA Atmospheric Variability Experiment to characterize the\nvariability of mid-tropospheric inversions are well under way. A field\nexperiment has been designed to obtain detailed and frequent rawinsonde, wind\nprofiler, and radiometer data during frontal passage and subsidence inversion\nconditions.\nThe pilot forecast exercise conducted by the Exploratory Development Group\nproduced mesoscale forecasts of winds, temperature, ceiling, visibility, and\nprecipitation during the winter season of early 1984. Quantitative evaluation\nof those forecasts has been completed by the T&E staff. The results of these\nanalyses will be forthcoming in early FY 1985.\nPlans FY 1985\nParticipate in the design and preparation of the PROFS 1985 forecast\nexercise, planned for mid-May to mid-August 1985.\nComplete the joint PROFS WPL project to evaluate the radiometer system\nfor use in short-term mesoscale analyses and forecasts.\nModify the RADAP algorithms as necessary, on the basis of Colorado 1983\nsevere weather data, for testing and evaluation during the 1985 forecast\nexercise.\nWEATHER MODIFICATION PROGRAM\nWMP\nThe Weather Modification Program (WMP) oversees the Federal-State\nCooperative Research Program in Weather Modification, which began in 1979. At\nthat time the U.S. Congress appropriated funds for a Federal-State cooperative\nevaluation of two ongoing programs, a North Dakota summertime program and a\nUtah wintertime program. Such Federal-State cooperative programs were one of\nmany recommendations to the Secretary of Commerce in 1978 by an independent\nWeather Modification Advisory Board appointed in response to the passage of\nPublic Law 94-490, which required that the Secretary of Commerce develop a\nplan at the Federal level whereby weather modification research activities\ncould be coordinated.\nThe responsibility for the performance of this Federal-State cooperative\nprogram was assigned to NOAA. NOAA in turn contracted with Colorado State\nUniversity in 1979 to develop a design for the conduct of the first two pro-\ngrams approved (i.e., the North Dakota and Utah programs). Various committees\nprovided recommendations for the conduct of field research programs in North\nDakota in 1980, 1981, and 1982 and in Utah in 1980-81 and 1982-83. In FY\n1983, Nevada was added to the program. In FY 1984, Illinois was added.\n41","Each state has different interests in weather modification. Scientific-\nally, North Dakota is concerned about the evolution of rain and hail in\nconvective clouds of the northern Great Plains; Utah's interests are in the\nscientific assessment of winter snow enhancement efforts in the mountains;\nNevada's research interests are the downwind effects of seeding for winter\nsnow in California; the research interests of Illinois are in summer rain\nprocesses as they pertain to stabilization of corn and soybean production.\nAll four programs, which are in different climatic regimes, are of broad\nregional and national interest and represent sizable State investments. In\nthe four efforts there is close cooperation among scientists and administra-\ntors of the programs and with the NOAA Program Manager.\nAccomplishments FY 1984\nCOOPERATIVE RESEARCH-ILLINOIS\nThe Illinois State Water Survey obtained NOAA funding and formally\nentered the Federal-State Cooperative Research Program in April 1984. Work in\nearlier years, in part through other NOAA support, established the\nPrecipitation Augmentation for Crops Experiment (PACE) Current sponsorship\nof the Illinois program will continue to support the PACE program in part.\nThe long-term goal of PACE is to determine whether agriculturally useful\nincreases in summer convective rainfall can be produced in the Midwest.\nToward this end, broad, basic scientific background studies were initiated in\nFY 1984, and staff and equipment appropriate for these tasks were increased.\nRadar echoes from an extensive, existing data base are being characterized in\nterms of patterns in rain cell development and evolution. Meteorological\nsatellite expertise was brought into the organization to initiate a range of\nconvective cloud studies. Soil moisture instrumentation was acquired and\ninstalled in several benchmark soils to study rain infiltration and soil\nsurface sealing. Also launched was a study of the agricultural economic\nimpact of wet-summer vs. dry-summer precipitation.\nCOOPERATIVE RESEARCH-NEVADA\nThis program is oriented to study the microphysical and dynamical aspects\nof the problem of \"area of effect\" in a region of the Central Sierra Nevada\nwhere operational and semi-operational seeding programs are being conducted in\nCalifornia and there is a potential for downwind effects of these programs to\nbecome manifest in Nevada.\nThe work is and will continue to be focused on three tasks: (1) trans-\nport, dispersion, and capture of seeding agents; (2) stable isotopes and ice\ncrystal growth in relation to liquid water locations in mesoscale systems; and\n(3) the distributions of liquid water and ice in Sierra Nevada winter storms.\nSome remarkable new concepts in wet-weather tracer technology are begin-\nning to emerge from this part of the Federal-State Cooperative Program in\nWeather Modification Research. The oxygen isotope ratio in snow (180/160),\nwhich is established when water substance freezes in a cloud, is providing a\nmeans to estimate where in a cloud and by what growth processes (vapor\ndeposition or accretion) snow crystals gather their mass. Silver sampling in\nsnow is demonstrating the confinement of ground-released particles (AgI) and\n42","is showing what portions of cloud volumes are reached by particle plumes in\nclouds over complex terrain. The use of two compositions of particles with\nsimilar size and mass distributions, one active and one inactive as an ice\nnucleant, is being developed to distinguish between cloud nucleation and\nscavenging processes. The implications with respect to effective delivery of\ncloud seeding material (or, e.g., to the dispersion of powerplant effluents)\ninto cloud systems is profound. All of these technologies have broad\napplication in basic cloud studies, weather modification, and air quality.\nCOOPERATIVE RESEARCH-NORTHDAKOTA\nThe current North Dakota ice-nucleant generators and flares were tested\nfor productivity at Colorado State University. A surprising result was the\nhigh variability among flares in the same cloud chamber, which raises\nquestions about controlling the cloud-treatment amounts.\nIn July, a preliminary study of sulphur hexafluoride (SF6) as an in-cloud\nplume transport and diffusion tracer was successfully conducted. The pio-\nneering results indicated that the circulation in a growing convective cloud\nwas very confined; continuous cloud base seeding generated plumes of only rela-\ntively small diameters (e.g., 100 to 500 meters) at a few thousand feet above\nthe seeding altitude. In the SF6 plumes there also was evidence of liquid-\nwater-to-ice conversion by AgI in some of the cloud penetrations.\nThe 2-D and 1-D modeling of North Dakota convective cells is continuing.\nGraupel appears to be the dominant growth form of precipitation in these model\nresults. Also, an investigation of the time between first and maximum echo\nheights was conducted for treated and nontreated cells. Treated cells, on the\naverage, may have shorter growth times than the nontreated. Analysis is\ncontinuing.\nCOOPERATIVE RESEARCH-UTAH\nA field program directed at defining the supercooled liquid water in Utah\nwinter storms and the trajectories of cloud hydrometeors and potential seeding\nWMP\nmaterial trajectories was conducted during January and early February 1983.\nThe program was terminated early because of excessive precipitation over all\nof Utah. Nevertheless, a very valuable data set was collected. One key\nanalysis to date has demonstrated the utility of the use of multiple remote\nsensors to study and monitor winter orographic clouds. The use of a dual-\nchannel radiometer to continuously monitor cloud water vapor and liquid, a\npolarized lidar to indicate the base height of liquid cloud layers and the\npresence and height of ice particles through the cloud volume, and a K-band\nradar (e.g., 1.79 cm) to indicate cloud top and to follow the transition from\nwater phase to ice phase in the cloud volume, provide in combination a power-\nful tool to monitor and measure the availability, transition, and budget of\ncloud water. From data collected with these sensors, microphysical patterns\nin cloud evolution are being defined that will allow for better prediction of\nliquid water (particularly for cloud modification and aircraft icing), in rela-\ntion to the structure of cold fronts. Additional studies of cloud transport\nover mountains are revealing the effects of meteorological trapping of cloud-\nseeding materials. The work is equally applicable to the trapping of emis-\nsions from powerplants and other sources in mountainous terrain.\n43","Plans FY 1985\nCOOPERATIVE RESEARCH-ILLINOIS\nFY 1985 will be the first full year of Illinois participation in the\nprogram. Analyses of radar echo evolution, based on the data acquired, will\nbe completed. Satellite cloud studies will be integrated with the radar\nstudies to identify cloud/echo types most likely to be suitable for increased\nprecipitation efficiency, and thus for further cloud physics studies by remote\nsensing and aircraft. The Illinois State Water Survey will acquire, on a\nshared basis with other states in the program, a GOES (satellite) receiving\nsystem. The Survey will modify its HOT (Hydrometeorological Operational Tool)\n10-cm radar to include a Doppler capability, which, with its existing CHILL\n(CHicago and ILLinois) 10-cm radar, will provide a dual-Doppler capability.\nPast Water Survey tracer work in convective clouds will be reviewed, as will\nthe physics of all previous weather modification efforts in Illinois. Soil\nmoisture measurements and economic models will be used to assess major impacts\nof real or hypothetical precipitation variations on agriculture production\ncapacity and water quality.\nCOOPERATIVE RESEARCH-NEVADA\nWork on several fronts, in accord with the three central tasks mentioned\nwith the FY-1984 accomplishments, will continue in conjunction with a field\nprogram during the winter and spring of 1985: (1) development of tracer\ntechnologies and studies of the spatial and temporal dispersion of seeding\naerosols; (2) studies of the temperature range over which the water has frozen\nto form the ice crystals and snowflakes reaching the surface in the project\narea; (3) development of new exotic chemical and isotope techniques for\nseeding assessment; (4) determination of the precipitation, supercooled liquid\nwater, and ice across the Sierra Nevada crest, using a surface network that\nincludes radars and a microwave radiometer; and (5) determination of the\nchemical makeup of the snow falling downwind of the Sierra Nevada crest.\nCOOPERATIVE RESEARCH-NORTH DAKOTA\nThe following items are the principal activities for FY 1985:\nAnalyses of the pioneering 1984 preliminary studies of simultaneous cloud\nphysics, and tracer data to determine plume and treatment characteristics\nover time and space.\nThe initiation of a comparative exploratory field experiment on\nin-cloud diffusion and treatment signatures for a relatively fast and\nslow reacting AgI compound.\nA Doppler radar investigation of in-cloud circulations for treated and\nnontreated cases.\nContinued 2-D modeling of the presumed North Dakota precipitation\nprocess.\n44","A laboratory development of an AgI-AgCl-salt mixture suitable for use as\na fast-acting ice nucleant in airborne flares.\nCOOPERATIVE RESEARCH-UTAH\nA winter-spring 1985 field research program will be conducted in the\nTushar Mountains. Key remote sensors will be utilized; these do indeed\nprovide a foothold on the future for positive monitoring, prediction, and\nmodification of supercooled liquid water, water-to-ice - transitions, and the\ndevelopment of precipitation. Meteorological trapping of seeding materials\nwill continue to be studied, since effective delivery is a crucial issue. New\ndata from 1985 will be integrated with the valuable 1983 data set for in-depth\nanalysis of both.\nWMP\n45","","Hugo F. Bezdek\nATLANTICOCEANOGRAPHICAND\nDirector\nMETEOROLOGICALL LABORATORY\nMiami, Florida\nDirector\nO/P\nDep. Director\nCooperative\nESG\nCRP WRP PROFS WMP\nInstitutes\nAOML\nPMEL\nGLERL\nGFDL\nNSSL\nWPL\nARL\nAL\nSEL\nThe Atlantic Oceanographic and Meteorological Laboratory (AOML) is\norganized to pursue basic and applied research programs in oceanography and\ntropical meteorology. Oceanographic investigations center on fluxes of\nenergy, momentum, and materials through the air-sea interface; the transport\nand composition (thermal and chemical) of water in the ocean volume; and\nhydrothermal processes of mineralization at seafloor-spreading centers.\nMeteorological research is carried out to improve the description, under-\nstanding, and prediction of hurricanes. The research program is enlarged by\nthe Cooperative Institute for Marine and Atmospheric Studies (CIMAS), a joint\nenterprise with the Rosenstiel School of Marine and Atmospheric Science of the\nUniversity of Miami. CIMAS enables NOAA and university scientists to colla-\nborate on problems of mutual interest, and facilitates the participation of\nvisiting scientists.\nAOML\nAOML's current research program concerns processes relating to climate,\nweather observation and prediction, marine assessment, marine observation and\nprediction, marine resources, and air quality.\nCLIMATE RESEARCH\nClimate research at AOML continues to focus on aspects of ocean heat\ntransport and storage in relation to interannual and longer-term variations of\natmospheric weather and climate. Increasingly, AOML activities in these areas\nmust be seen as part of the NOAA contribution to national and international\nprograms for climate research. The scope of problems being addressed more and\nmore requires extensive cooperation and coordination between groups, especially\nfor oceanographic field programs. Tradition and convenient access to\nsea-going research facilities result in a research program with emphasis on\ncollection and analysis of oceanographic data. There is, however, increasing\n47","use of numerical models for making interpretations and predictions based on\nthe observations. The AOML program in climate research is conveniently\ndescribed within the two categories of tropical ocean climate studies and\nsubtropical Atlantic climate studies.\nAccomplishments FY 1984\nTROPICAL OCEAN CLIMATE STUDIES\nTropical ocean climate studies at AOML consist of participation in the\ncontinuing NOAA EPOCS (Equatorial Pacific Ocean Climate Studies) program,\nanalysis and interpretation of tropical ocean data collected during the First\nGARP Global Experiment (FGGE) of 1979, and beginning work in connection with\nthe international program TOGA (Tropical Ocean Global Atmosphere), which has\nobjectives on the global scale very similar to those of EPOCS on the scale of\nthe tropical Pacific. The common focus of this work is to describe, under-\nstand, and predict the large-scale air-sea interaction processes associated\nwith the major mode of interannual large-scale climate variation - the El\nNiño/Southern Oscillation phenomenon.\nDuring 1984, intensive effort was committed to compilation and processing\nof extensive data sets collected for description and analyses of the historic\nEl Niño event of 1982-83. The data sets available include the following:\nCTD (conductivity-temperature-depth) and current measurements from 13\ncruises along 85°W from 1981 through 1983. A draft manuscript on\ndescriptive aspects of these sections has been completed. An early\nconclusion is that it appears possible to describe the thermocline\nvariations in the eastern tropical Pacific during El Niño in terms of a\nsmall number of normal modes.\nMore than 3,000 temperature profiles taken by XBT (expendable bathyther-\nmograph) from ships of several countries and the NOAA research\naircraft. Analyses of these data show isotherm patterns suggestive of\nKelvin and Rossby waves.\nApproximately 7,000 buoy days of data from satellite-tracked drifting\nbuoys that, in companion with about 18,000 buoy days of data collected\nprior to the event, reveal that major changes in the surface currents are\nin fact associated with El Niño. The earlier data were used also to\ncomplete a major investigation showing that prominent long waves, of 20-\n30 day period, intermittently observed in satellite SST (sea surface\ntemperature) data, are due to shear instability of the zonal currents,\nand appear to have a strong influence on the equatorial ocean heat\nbudget.\nAn international workshop was convened at AOML to review observations of\nthe El Niño shortly after its passing, and a draft atlas summarizing observa-\ntions from many observers and institutions was completed. AOML has also made\nspecial effort to foster cooperative data collection and research activities\nwith colleagues in Latin America. During FY 1984, two scientists from Ecuador\nwere guests of the laboratory and CIMAS.\n48","Using data obtained during the 1979 FGGE (First GARP Global Experiment),\nanalyses and interpretation were continued to document the processes that are\nmost important in the heat budget of the surface layers of the equatorial\nIndian and Atlantic Oceans.\nAn investigation was also initiated into the reality of and possible\nmechanisms for an apparent negative correlation between E1 Niño in the Pacific\nand hurricane frequency in the Atlantic region.\nIn connection with all of these activities, scientists of AOML partici-\npated in numerous scientific meetings, seminars, and workshops convened to\nreview and share progress on understanding of larger scale tropical air-sea\ninteraction and for formulation of plans for the international TOGA program.\nSUBTROPICAL ATLANTIC CLIMATE STUDIES\nThe North Atlantic Ocean is believed to be particularly important for the\nlarge-scale meridional heat transport processes required by the prevailing\nclimate of the earth. Knowledge of the ocean heat transport and its\nmechanisms are required for understanding changes of weather and climate on\ndecadal time scales, and probably for modeling larger scale long-term ocean\ncirculation processes of all kinds. During the past two years, work has\nconcentrated on observational studies of the Florida Current, which have the\nobjective of developing economical means of monitoring both the mass and the\nheat transport of this limb of the North Atlantic subtropical gyre over\nextended time periods. A 2-year time series of directly measured flow was\nused to evaluate and calibrate potential monitoring methods for the current.\nBoth induced electrical potential difference and sea level differences were\nshown to offer excellent potential as monitoring techniques, the former with\nprobably somewhat greater accuracy, and the latter with greater reliability.\nBoth are economically and logistically attractive monitoring technologies, and\nwork was initiated for transferring the monitoring operation to NOS (National\nOcean Service). .\nMore detailed investigations of the variation of the current, using EOF\n(empirical orthogonal function) analyses, revealed a definite winter/summer\nAOML\npattern in the EOF intensities, and showed the strongest EOF to be associated\nwith a change in the flow on the western side of the current.\nThe priority goals of the Florida Current having been met, observational\nresources were shifted to new focus with a research cruise to investigate the\nimportance of flows along the topographic rise east of the Bahamas.\nPlans FY 1985\nTROPICAL OCEAN CLIMATE STUDIES\nThe main emphasis in these studies during FY 1985 will continue to be on\ndocumenting and analyzing the El Niño event of 1982-83. The El Niño oceano-\ngraphic atlas summarizing NOAA and other observations will be published.\nAnalyses will be made and reports written on variations of hydrographic struc-\n49","ture observed in the eastern tropical Pacific during the event. Analysis of\nnormal surface currents as determined by satellite-tracked drifting buoys will\nbe completed as a basis for quantifying the circulation anomalies experienced\nduring E1 Niño. Hypotheses concerning the effects of circulation anomalies on\nSST during the onset of El Niño will then be tested.\nData collected during FGGE will be used to compute the relative impor-\ntance of various physical processes in the mixed layer for the Indian Ocean,\nto produce an atlas of the marine meteorological and heat budget fields in the\nIndian Ocean, and to estimate the temporal and spatial scales of variability\nin the equatorial Atlantic and Indian Ocean sea surface temperature and\nsurface wind fields.\nA major acceleration of climate-related research into the tropical oceans\nwill occur with implementation of the TOGA program in FY 1985. Present plans\nare for a major U.S. thrust in the tropical Pacific, where AOML has been\nactive with EPOCS in recent years. Among the priority activities to which\nAOML will contribute in this region are a \"Real Time Component,\" and a \"Rapid\nResponse Experiment.\" For the Real Time Component, special effort will be\nmade to compile and interpret observations of atmospheric and oceanic varia-\ntions on time scales of a few days to a very few weeks in order to make\nprojections of climate anomalies both to guide research and to provide a basis\nfor advisories to the socio-economic sector. One of the principal scientific\nuses of the projection will be to trigger the Rapid Response Experiment in\nwhich observational resources will be focused on obtaining more detailed\ninformation on the development of El Niño in the ocean. AOML scientists will\ncontribute to planning and implementation of both of these activities.\nCooperative relationships with institutions in Latin America will be used for\ndeployment of satellite-tracked drifting buoys and collection of temperature\ndata from regional vessels to provide data input to the Real Time Component,\nand contribute to the Rapid Response Experiment. Drifting buoys are well\nsuited to these uses as their data are routinely reported in real time.\nTemperature data also will be telemetered via satellite as soon as the\nformatting and transmitting equipment can be purchased and installed on the\nobserving vessels. It is planned that Latin American scientists will continue\nto be given opportunity to visit AOML for training and cooperation in analysis\nof the data collected in the cooperative observing programs.\nAOML will participate in two different approaches to use of models for\nintegration and interpretation of data from the Real Time Component. The GFDL\nocean model will be set up on a computer at the National Meteorological Center\n(NMC) and used for simulation studies of the 1982-83 event, and to compute the\nocean response to surface winds for comparison with data compiled in the real-\ntime component. A scientist from AOML will participate in and guide these\nnumerical modeling experiments at NMC. The GFDL model is large and produces\nvery detailed output. Analysis of the model results is itself a major task.\nAt AOML, work will begin on development of a four-dimensional data\nassimilation procedure capable of assimilating observations of oceanographic-\natmospheric fields into simpler numerical models of the relevant systems,\nwhatever the distribution of those observations in space and time.\n50","SUBTROPICAL ATLANTIC CLIMATE STUDIES\nAnalysis of the direct measurements of the Florida Current will be com-\npleted to provide as complete a kinematic and dynamic description as possible\nof the temporal and spatial variations of this major current. New observa-\ntions will be made in the Caribbean Sea and the Windward Passage to determine\nin more detail the sources of the Florida Current transport and variability.\nData analysis on sea level and pressure gauge data will continue with a view\ntoward optimizing the use of sea level data and of extending the sea level\nobserving network throughout the Antilles and the Caribbean Sea. This network\nis expected to be accomplished in the context of the sea level program of the\nIntergovernmental Oceanographic Commission.\nWork will continue on application of EOF and other kinds of statistical\nanalysis and modeling procedures to all the data from the Florida Straits, to\nidentify the active modes of variation as quantitatively as possible. Optimal\ninterpolation methods will be used to evaluate each of a number of candidate\nobserving systems.\nIt is envisaged that climate-related studies of AOML in the subtropical\nNorth Atlantic will gradually evolve into a major NOAA commitment to a larger\nnational or international program such as the TOPEX ([Ocean] Topography\nExperiment) program or the World Ocean Circulation Experiment (WOCE),\ncurrently in discussion and preliminary planning for the next decade.\nWEATHER OBSERVATION AND PREDICTION\nAOML is NOAA's primary focus for research in tropical meteorology and\nhurricanes. Research teams concentrate on field programs, numerical hurricane\nmodeling, and theoretical studies of hurricanes. The laboratory's hurricane\nfield program makes use of NOAA research aircraft to acquire unique data sets.\nAOML interacts with the National Hurricane Center (NHC) and NMC of the\nNational Weather Service (NWS) in problems of hurricane prediction, with the\nNational Center for Atmospheric Research (NCAR) on scientific investigations\nAOML\nof the inner cores of hurricanes, and with GFDL in the area of hurricane\nmodeling.\nAccomplishments FY 1984\nOBSERVATIONAL STUDIES OF HURRICANES\nMicrophysics\nThe results of a study on drop size distributions in tropical convection\nin hurricanes indicate some departure from the Marshall-Palmer fit to the drop\nsize distributions. A gamma distribution functional fit was found to give the\nbest fit to the observed data set. A simple parameterization of rain was\nformulated on the basis of this fit.\n51","The gamma fit to drop size distributions and a recently reported new fit\nthe Gunn and Kinzer drop terminal velocity data were used to derive a\nto\nrelationship between the Doppler mean velocity and the radar reflectivity\nfactor. This relationship is required in the most common method of separating\nthe terminal fall speed motion from the air motion in Doppler radar data.\nA study on the distribution of ice in the convection of Hurricanes Ella\n(1978), Allen (1980), and Irene (1981) showed that above the 0°C isotherm\nlevel, only updrafts > 5 m s-1 contained liquid precipitation. Downdrafts\ncontained very high (> 150 1-1) concentrations of ice particles. These\ndowndrafts were always adjacent to updrafts > 5 m s-1 Graupel was the\npredominant particle type in the convective regions, and irregular particles\nsimilar in appearance to aggregates predominated elsewhere.\nAn analysis correlating particle type and concentration with radar dis-\nplays for Hurricanes Allen (1980) and Irene (1981) was completed. This study\ndocumented that the regions of high (>30 dBZ) radar reflectivity above the 0°C\nisotherm were positively correlated with both strong updrafts and the\noccurrence of liquid precipitation. Strong negative radial gradients of radar\nreflectivity at the outer edge of the eyewall were often associated with down-\ndrafts and high concentrations of ice particles.\nConvective and Mesoscale\nThe analyses of the airborne Doppler radar data from Hurricane Debby\n(1982) were completed, and the results clearly indicate that the NOAA airborne\npulse-Doppler radar is a very good tool for determining mesoscale wind fields\nover large regions in a hurricane environment.\nFollowing the success of the Debby analysis, a similar analysis of the\nairborne Doppler data for Hurricane Alicia (1983) was started. From Alicia,\nwe have some of the first examples of vertical incidence Doppler radar data\nfrom aircraft. These data give a direct measurement of the vertical air\nmotion (plus the particle fall speed) at different altitudes above and below\nthe aircraft along the flight track. A technique was developed for removing\nthe particle fall speeds from the vertical incidence data. The vertical\nvelocity cross sections constructed using this technique show details of the\nvertical air motion in and around the eyewall. For the first time, mesoscale\nupdraft motion (0.5-1.0 on average) was actually measured above the\nbright band in the nonconvective region adjacent to the eyewall.\nA major accomplishment was the production of a color movie of the digital\nradar data recorded during the landfalls of Hurricanes David and Frederic.\nThe movie has been shown at numerous conferences and meetings during the year\nand is an excellent vehicle for showing the time evolution of the more impor-\ntant precipitation features of these storms. A similar movie for the landfall\nof Hurricane Alicia is in production.\nSynoptic-Scale\nOmega dropwindsonde (ODW) data gathered during Hurricane Debby (1982)\nwere analyzed. The impact of the data on the operational objective analyses\n52","and the dynamical hurricane track models was evaluated as part of a coopera-\ntive effort with NHC and NMC. The dynamical Movable Fine Mesh (MFM) hurricane\ntrack model can be initialized with either the operational Hough analysis or\nan optimum interpolation analysis. The shortest wave resolved by the analyses\nhas an east-west wavelength of about 1500-2000 km. Both analyses were unable\nto resolve the hurricane vortex or a cutoff low located about 500 km to the\nnorth of Debby's center. Each of these circulations had a horizontal scale of\nabout 500 km. The cutoff low was clearly defined by the ODW data, and it had\na significant influence on Debby's track. The resolution of the objective\nanalyses that initialize the MFM must be improved if circulation features with\nscales of 500 km are to be resolved. MFM track forecasts were found to be\nvery sensitive to small variations in the initial analyses.\nFinal processing of the ODW data for Hurricane Olivia (1982) was com-\npleted, and the data were distributed to scientists at several laboratories\nand universities.\nA study aimed at gaining a better understanding of the effect of aircraft\nturns on the accuracy of ODW winds was completed. Data collected by the\nOffice of Aircraft Operations (OAO) during test flights in 1982 and 1983, when\none of the P-3's made several turns near a stationary ODW on the ground, were\nanalyzed for this purpose. The capabilities of three wind-finding algorithms\nwere evaluated, and the advantages of each algorithm were determined.\nAir-Sea Interactions\nSoftware was developed for viewing Doppler radar radial velocities in the\nhurricane boundary layer in a range-height mode and for properly detecting and\nremoving surface contamination of the data. Boundary-layer wind structure in\na developing principal rainband in Hurricane Debby (1982) was investigated\nusing airborne Doppler radar data as well as aircraft measurements of wind and\nthe thermodynamic variables at several levels. Preliminary results indicate\nthat the airborne Doppler radar is an effective tool for study of the hurri-\ncane boundary layer. Detailed vertical profiles of the horizontal wind are\npossible from the 200-m level upward with a resolution of 150-200 m. Even\nAOML\nmore detailed profiles may be obtained through adjustments to flight legs.\nA data base of more than 100 land and ocean observation platforms was\ndeveloped for Hurricane Alicia, which struck the Texas Gulf coast in August\n1983. These data have been composited with respect to the storm center for\nthree analysis periods: (1) over the open Gulf of Mexico, (2) at landfall, and\n(3) several hours after landfall. During landfall, the outer rainbands on the\neast side of the storm continued to develop in a preferred area of mesoscale\nlow-level confluence and spiral northwestward, contributing to heavy rainfall\nand damage in the Galveston Bay coastal region.\nA preliminary, color version of the sea-state catalog (in loose-leaf\nform) was begun. The catalog consists of color Hasselblad photos taken during\nreconnaissance overflights of Hurricanes Alicia and Dean during 1983. Surface\nwind speeds from 12 to 33 m s-1 are represented. The purpose of this project\nis to improve the accuracy of sea-level wind speed estimates based on visual\nobservations of sea state taken by U.S. Air Force weather reconnaissance\nobservers.\n53","Detailed slide sets of vertical sea-state photos (mostly black and white)\nwere prepared and presented to the 54th Weather Reconnaissance Squadron at\nAnderson Air Force Base, Guam, and the 53rd and 920th Weather Reconnaissance\nSquadrons at Keesler Air Force Base, Miss., for their use in training\nprograms. Workshops on sea-state wind estimation were given at each location.\nIn addition, an overview of the efforts to improve sea-state surface wind\nestimation as well as the potential of remote microwave sensing of surface\nwinds was presented at the Pacific Command Tropical Cyclone Conference in\nTokyo.\nHURRICANE TRACK PREDICTION\nThis program is conducted jointly with the National Hurricane Center. A\nfinal version of the scan analysis for deep-layer mean (DLM) winds to be used\nto initialize the SANBAR (Sander's Barotropic) model was completed and\ntested. Forecasts were run using this analysis package, combined with the old\nprognostic model, using archived data for the 1979 to 1982 hurricane seasons.\nThis new package demonstrated an improvement over the former operational\npackage at the 12- to 72-h forecast intervals (error reduced by 22 km at 72 h)\nfor the 4-year sample. The reduction in average forecast errors was shown to\nbe significant (at the 95% level) from 24 to 48 h.\nWith a fine-grid version of SANBAR, forecasts were made for Debby (1982)\nusing the ODW data available on 15 and 16 September. On 16 September, the ODW\ndata had a much greater effect than on 15 September, both in the analysis and\nin the forecast. The scan analysis was able to assimilate the extra data\naccurately, resulting in the reduction of the 24- to 72-h forecast errors.\nThe DLM scan analysis is now on the AFOS (Automation of Field Operations\nand Services) and FAX circuits. In addition, at the requests of forecasters\nat the San Francisco and Hawaii Weather Service Forecast Offices, the scan\nanalysis has also been implemented for the eastern Pacific to generate upper\nlayer (200-600 mb), lower layer (600-1000 mb), and deep-layer (100-1000 mb)\nmean and shear (upper layer minus lower layer) maps for the AFOS and FAX\ncircuits.\nTesting was done using DLM wind data derived from the VISSR (Visible\nInfrared Spin Scan Radiometer) Atmospheric Sounder (VAS) in cooperation with\nthe National Environmental Satellite, Data, and Information Service/Develop-\nment Laboratory in Madison, Wis. The VAS-derived winds were used for eight of\nthe Hurricane Debby (1982) cases and for nine cases (Hurricanes Alicia, Barry,\nand Chantal) from the 1983 season. The small number of cases available for\nthe 1982 and 1983 hurricane seasons prohibits conclusive results.\nRecent research with statistical hurricane track prediction models has\nproduced results dealing with the orientation of grid systems in statistical\ntropical cyclone track prediction models, and with sampling errors in statis-\ntical models of tropical cyclone motion. The orientation method developed is\nbeing applied to a revised operational forecast model at NHC. Preliminary\ntests indicate that the new method has a strong potential for significantly\nreducing forecast errors, particularly by substantially reducing the slow\nspeed bias characteristic of previous models.\n54","HURRICANE VORTEX DYNAMICS\nStudies involving the performance of our prototype nonhydrostatic\nhurricane model were conducted and have shown a vortex-scale evolution of the\nmodel when the model is integrated with a conventional Kessler-type micro-\nphysical parameterization and a bulk ice-phase microphysics parameteriza-\ntion. They have also shown mesoscale features in the ice model that were\nforced by melting of ice particles. These studies have established the\nimportant role of ice-phase processes in the model simulation and have\nindicated the potentially important role of cloud microphysical processes in\nthe mesoscale structure of tropical cloud systems.\nTwo new sets of experiments were performed to confirm and elucidate the\nrole of ice-phase microphysics in the structure and evolution of this axisym-\nmetric model. In the first set, two key factors in the ice-phase physics,\nproduction rate of precipitating ice and bulk fallspeed of the various types\nof ice particles, were isolated by judicious simplification of the original\nice-phase parameterization. Results show that melting ice always creates a\ncharacteristic downdraft signature below the zero-degree isotherm, and that\nthe strength and horizontal extent of the downdrafts depends on the terminal\nfallspeed of the ice particles. In the second set of experiments, the\ntransient growth of parameterized ice particles in the earliest stages of\ncloud formation is being examined for a different parameterization of\nsuspended ice crystal nucleation.\nObservations from Hurricanes David of 1979 and Gert of 1981 have led to\nformulation of a conceptual model of the asymmetric structure of hurricanes.\nIn this model, a stationary band of convection, termed the Stationary Band\nComplex (SBC), extends outward toward the east side of the vortex. The SBC\nlies in a part of the vortex where the Rossby number (defined in terms of the\nlocal azimuthal mean wind and the distance from the storm center) is of order\nunity. It coincides with a convergent asymptote in the streamline analysis\nand marks the innermost limit to which relative environmental flow can\npenetrate the highly rotational core of the vortex. An axisymmetric convec-\ntive ring can develop from the SBC as it becomes more circular and wraps\naround the core of an intensifying hurricane. The cyclic intensity changes\nassociated with these latter features are, however, confined largely to the\nAOML\nvortex core where the Rossby number can be of order 102 Thus, an intense\nhurricane may be characterized as an axisymmetric, cyclicly varying core\nembedded within an asymmetric, largely steady-state envelope that resembles\na\nweaker hurricane or a tropical storm.\nOn 17 and 18 August 1983, 30 h of continuous aircraft and radar observa-\ntions were collected in Hurricane Alicia. Analysis of these data is largely\ncomplete and shows contraction of the original evewall, formation of an outer\nconvective ring, and track variations associated with moving reflectivity\nfeatures in the eyewall.\nHURRICANE MODELING\nThis modeling work is based on a long-range plan to understand and\npredict the motion of a hurricane. Although there are several operational\nmodels for hurricane prediction, it is recognized that basic studies of\n55","various physical and dynamical factors affecting the motion, as well as\nchanges in intensity, are needed to make substantial improvements in the\naccuracy of prediction. The major question is to understand interactions\namong various scales of atmospheric motions and between different dynamic\nregimes. Progress in such understanding requires further tests with numerical\nmodels. To facilitate individual studies, which may range from the cloud\nscales of hurricane internal dynamics to the synoptic scales of tropical\ncirculations, and also to ensure an efficient synthesis of these studies, a\ngeneral-purpose base model is under development, using an accurate and\nflexible numerical method for grid-nesting. The method, tentatively called\nQSTING (Quasi-Spectral Time Integration on Nested Grids), can also be applied\nto other meteorological models that require high resolution in limited\ndomains.\nOf the mathematical-numerical problems in grid nesting, one is the Gibbs\nphenomenon, which may manifest itself as small, but far-reaching, oscillations\nof a field variable, when a sharp peak that is well resolved in a high-\nresolution domain is projected on outer domains of lower resolution. This is\na serious problem with a hurricane model, where sharp wind maxima and a\npressure minimum are expected to occur in the inner mesh of the highest\nresolution. We have found that a filter on fine-mesh fields, at the time of\nprojection to the coarse-mesh domain, can adequately attenuate false oscilla-\ntions, without damping the explicitly time-carried fields of the fine-mesh\ndomain. Note that terms \"fine\" and \"coarse\" are used in a relative sense. In\nour multiple-nested model, a mesh is fine and coarse in relation to its super-\nmesh and submesh, respectively. By moving inner domains as a hurricane moves,\nthe Gibbs phenomenon arising from the intense hurricane core can be thus\ncontrolled.\nEven with the moving-mesh model, however, signals of various scales still\ncross the interfaces of nested domains, because of local advection and wave\npropagation. The limits imposed by the change of resolution cannot be\novercome by choice of a numerical method. Those small-scale signals that\ncould not be resolved or would be severely distorted in the coarse mesh must\nbe dissipated within the fine mesh, before they reach the interface. The\npractical limit of transmissible short waves further depends on the computa-\ntional dispersion property of particular numerics employed by a model. The\nQSTING method allows four times more usable information to be carried than the\nfinite difference method would for the same resolution. Even then, short\nwaves below the limit must be removed before they reach the interface. To\nachieve the desired effect, we have introduced spatially variable filters with\nfiltering power increasing outward to the interface. Since theoretical means\nto help the design of such filters are limited, we have had to depend on\nempirical tests with a one-dimensional model, and our present solution to this\nproblem is not as definitive as we wish it to be. It is believed, however,\nthat we have reached the point that further studies should be made in the\ncontext of physically more realistic spectral mix, which is not available in\nthe one-dimensional test model.\nThe question of the physical validity of using a nested-grid model for\nhurricane prediction studies is not trivial, when we consider the role of\ncumulus convection in the hurricane and the need for incorporating mesoscale\ndynamics. There are many studies in the meteorological literature where\nnested grids or variable resolution models have been used. In most of them,\n56","however, the outer region of coarser resolution is merely a buffering space of\ninner activities. With the present model of superior numerics, there is a\ngreater possibility of simulating truly two-way interactions between the\nhurricane inner core and its synoptic environment, provided that the major\nportion of predictable information is carried in the scales that are\ncomparable with, or greater than, locally defined radii of Rossby deforma-\ntion. The deformation radii vary from a few tens of kilometers in the\nhurricane core to a thousand in the tropical synoptic environment, and the\nresolution of a model may vary in proportion. A convincing test of this\nsimple speculation requires a three-dimensional nested-grid model. The\npresent version being two-dimensional, there is still much work to be done.\nOBSERVATIONAL STUDIES OF THE SOUTH FLORIDA SEA BREEZE\nThe field phase of the sea-breeze experiment was designed to provide a\ndescription of the mixed layer, cloud layer, and evolution of the sea-breeze\ncirculation from shortly after sunrise until midafternoon when deep convection\nis normally prevalent. The role of the sea breeze in organizing the develop-\nment of deep convection is being examined. Airborne Doppler radar data were\ncollected on two days. These data are being used to specify the kinematic\nstructure of mesoscale precipitation lines that were initiated by the sea-\nbreeze circulation.\nThe analyses of the flight-level data have concentrated on comparing and\ncontrasting the structure of the sea-breeze circulation on one day in 1980\nand on a second day in 1981. The evolution of deep convection in the 1980\ncase was strongly influenced by a layer of very dry air between 850 and 700\nmb. Deep convection occurred near the flight track, but the rainfall did not\nbegin until very late in the day. On the other hand, the 1981 case was\ncharacterized by profiles of temperature and moisture that were near the\ntypical climatological values. Interpretation of the data is aimed at\nunderstanding the role of the sea-breeze circulation in the timing of deep\nconvection.\nPreliminary analyses of airborne Doppler radar data from two of the sea-\nbreeze flights have been completed. On one of the two days, high-quality data\nAOML\nwere recorded of a mesoscale precipitation line that was initiated by the sea-\nbreeze circulation. Westward propagation of the line and its vertical struc-\nture may have contributed to the rainfall production. The representativeness\nof this case is being examined through study of FACE (Florida Area Cumulus\nExperiment) radar data.\nPlans FY 1985\nOBSERVATIONAL STUDIES OF HURRICANES\nMicrophysics\nThe analysis of microphysical data in conjunction with radar data from a\nhurricane water budget experiment will dominate FY-1985 activities if the\nexperiment is completed this hurricane season as planned. Detailed analyses\n57","of the water contents and fluxes and transports will be completed for all\nflight segments and coordinated with Doppler radar and conventional radar data\nanalyses.\nDocumentation of the two-dimensional image processing will treat the\nartifact rejection and the ice/water discrimination in detail, and a complete\nprogram listing will be included.\nThe ice data sample that has been reduced and surveyed will be analyzed\nin relation to dynamical features of the storm. An attempt will be made to\ncomposite the data with respect to updrafts in the eyewall. The data will be\ninterpreted according to where the source regions of the ice occur, and the\nnucleation and/or multiplication processes necessary to produce the observed\nice particle distributions.\nConvective and Mesoscale\nThe analyses of the convective and mesoscale features of Hurricanes\nDavid, Frederic, and Alicia will be completed. During the landfall of\nHurricane Alicia, radar data were recorded at several elevation angles\napproximately three times each hour. Software will be written to display\nthese data in constant-altitude plan position indicator format. The three-\ndimensional structure of the convective-scale and mesoscale features in\nHurricane Alicia will be examined with both land-based and airborne radars.\nIf nature supplies a suitable storm during the 1984 hurricane season, a\nhurricane eyewall experiment will be carried out. Analysis of the resulting\ndata will begin in 1985.\nSynoptic-Scale\nCooperative studies with NHC and NMC will continue to examine the effect\nof the ODW data on the operational analyses and hurricane track models. ODW\ndata collected during the 1984 hurricane field program will be processed and\ndistributed to other institutions. The data will be used in diagnostic and\nprognostic studies of hurricanes and in the evaluation of remote soundings\nfrom VAS.\nAir-Sea Interactions\nThe Doppler radar study of Hurricane Debby's boundary layer will be\ncompleted.\nThe landfall study of Hurricane Alicia will be continued with analyses of\nthe gust and damage fields and their relationship to the precipitation struc-\nture. The surface temperature dew point, and sea surface temperature fields\nwill be investigated for evidence of adiabatic cooling, dry air intrusion, and\nupwelling.\nIt is planned to acquire additional color sea-state photographs for use\nin developing color-related descriptors of sea-state corresponding to Beaufort\ncategories 3 through 19. In addition, high-altitude photos will be acquired\nas part of other experiments and added to the sea-state catalog.\n58","During the Air-Sea Interaction Experiment planned for the 1984 hurricane\nseason, photos will be compared with stepped-frequency microwave radiometer\nmeasurements as well as with surface winds measured by air-deployed drifting\nbuoys. This study will also use highly reliable inertial navigation system\nflight-level wind measurements made near cloud base, and models of the\nplanetary boundary layer (PBL), to reduce flight-level winds to the surface.\nAirborne Doppler radar measurements in the PBL will also be used for\nestimating surface winds.\nHURRICANE TRACK PREDICTION\nWith the revised operational barotropic model, forecasts using ODW and\nVAS-derived wind data available from the 1984 hurricane season will be veri-\nfied. The results for the 1984 season, combined with the results from the\n1982 and 1983 seasons, will be used to suggest and/or make appropriate modifi-\ncations to the model for best use of the additional data sources.\nResearch to develop an objective analysis scheme for the large-scale\nenvironment of hurricanes, which incorporates ODW and other available data\nsuch as rawinsondes, NOAA P-3 data, and Air Force reconnaissance data, has\nstarted. Gridded temperatures, moisture, and wind fields for Hurricane Debby\n(1982) will be produced at 50-mb intervals using a spline analysis package\n(SAP) coupled with a vertical filtering scheme. Horizontal filtering with the\nSAP will make it possible to remove the larger scale components of the data\nfields and examine the smaller scale components that will be subjected to\nstatistical optimum interpolation. Development of this optimum interpolation\nscheme will be based on simple statistical assumptions and dynamical con-\nstraints. The goal is to retain information on the vortex scale and synoptic\nscales while filtering out information on the gravity wave and convective\nscales.\nHURRICANE VORTEX DYNAMICS\nAnalysis of the ice nucleation experiments with the prototype nonhydro-\nstatic hurricane model will be completed. Some time will be devoted to\nAOML\nmodification and simplification of the original ice-phase microphysics that\nwill make it more economical and realistic.\nThe details of a set of numerical experiments, including initial and\nboundary conditions, have been formulated to investigate the interaction\nbetween an isolated vortex and its environment, and its effect on hurricane\nasymmetry and motion. A quasi-spectral multinested-grid numerical model will\nbe used in a barotropic, primitive equation (one-layer, shallow-water) form on\na beta plane. The influence of divergence and advective nonlinearities will\nbe evaluated in a parameter range, relevant to hurricanes, that has not\npreviously been investigated. Near the vortex center, the local Rossby radius\nof deformation will be of the same order as the vortex scale, and the Rossby\nnumber will be very much greater than 1.\nThe analysis of the Hurricane Alicia data will be completed. These data\nappear to confirm earlier work on convective rings and the SBC. They also\nprovide insight into the origin of convective rings.\n59","HURRICANE MODELING\nProcedures for moving the nested grids will be tested. The model will be\nused in a theoretical study of vortex motion on a beta plane. Studies of the\nhurricane boundary layer will be carried out.\nOBSERVATIONAL STUDIES OF THE SOUTH FLORIDA SEA BREEZE\nThe airborne Doppler radar observations of the development of deep con-\nvection in the sea-breeze convergence zone will be completed and published.\nThe analyses of the 1980 and 1981 aircraft data will be completed and\ndocumented.\nTROPICAL WIND ANALYSIS\nNew research directed at objective analysis of ATOLL (Analysis of the\nTropical Ocean Lower Layer) and 200-mb winds to extract information on the\nAtlantic tropical circulation is under way. The ATOLL analysis is an invalu-\nable, virtually untapped data source. Objective analysis techniques will be\napplied to these data for the development of both a climatology and a history\nof quasi-steady and propagating disturbances for 1975 through 1983. During\n1985, it is planned to complete the transfer of grids to AOML's mainframe\ncomputer system; the evaluation of raw data coverage; and the 10-day and\nmonthly means for individual years and composites (9-year averages). This\nclimatology will be issued as a technical report in collaboration with NHC.\nMARINE ASSESSMENT\nA major goal of the AOML research program in marine assessment is to\ndevelop an understanding of ocean processes, their variations, and the effect\nof these variations on ocean resources, especially living marine resources.\nPresent research projects include (1) Transformation and Assimilation of\nPollutants [by Natural Processes] (TAP) and (2) Pollutant-Particle Relation-\nships In the Marine Environment (P-PRIME), in which natural processes are\nstudied to develop information essential to addressing specific environmental\nproblems.\nAccomplishments FY 1984\nTAP\nIn FY 1984 AOML continued the development of interactive biological-\nchemical models of metal speciation as it relates to effects on ocean\nplanktonic populations that serve as food sources to larval fish.\nIn cooperation with the SEFC (Southeast Fisheries Center), AOML conducted\na cruise to the New York Bight aboard the NOAA Ship Researcher in January\n1984. The purpose was to apply AOML-SEFC toxic metal/organic matter/plankton\ninteraction models to highly anthropogenically impacted waters and to test\n60","hypotheses regarding kinetics of formation of organic ligands in temperate,\nrather than tropical or subtropical, waters. Cruise results include the\nfollowing:\nThe New York Bight, although it appears to have a substantial\nchelation capacity for trace metals, appears to have an unusually small\noverall buffering capacity for acids.\nSewage sludge, regardless of age and pretreatment, does not appear to be\nnecessarily deleterious to either plankton or bacterial populations. In\nfact, under some conditions, e.g., nitrogen limitation, the addition of\nsludge may be beneficial to the productivity of the planktonic community.\nPresent, commonly used, analytical methods for \"Total Metal\nConcentrations\" may be inherently artifactual in that they appear to be\ndependent upon the quality of dissolved organic material in the seawater\nsample analyzed. Methods tested included Anodic Stripping Voltammetry\nand Co-precipitation Atomic Absorption Spectrophotometry.\nOrganic compounds (triglycerides) formed in cold waters are not\ninherently different than those formed in subtropical and tropical\nwaters, and their autoxidation and condensation result in fulvic and\nhumic materials with significant chelation capacity for metals. In fact,\nwaters in the New York Bight Apex, near Montauk Point, Long Island, and\noff Georges Bank all had an excess of chelation capacity; i.e., dissolved\nmetals were 100% complexed.\nAlthough complete, the complexing of metals in New York Bight waters is\nfragile in that almost any perturbation of the system releases free\nmetal. These perturbations include collection and storage of samples and\naddition of triglycerides in the form of fish liver oil. Both of these\nprocedures resulted in the release of free metals in samples collected.\nP-PRIME\nIn FY 1984 AOML continued to contribute to understanding of the fate of\nriver-borne pollutants at river/ocean interfaces. The basic hypothesis tested\nAOML\nwas that river deltas act as irreversible sinks for some pollutants that are\nscrubbed from the river outflow by biogenic and inorganic particles. Efforts\nwere focused on the outflow of the Mississippi River, which represents the\ndrainage from 41% of the contiguous United States. Specific results from the\nFY-1984 program include the following.\nDetermination of the combined particulate and dissolved river burden for\nlead clearly indicates a reduction of approximately 40% from levels in\nthe mid-1970' S. This is an apparent result of legislated reduction of\nlead in gasoline (gasoline additives account for 10%-12% of lead consumed\nin the United States and are the major source of pollutant lead) that was\neffected in the mid-1970's.\nA model was developed using distribution coefficients (K to define\nthe partitioning of pollutants, e.g., lead and cadmium, between river-\ndissolved and particulate fractions. This model allows definition of the\ndissolved load at a river outfall for a given total pollutant burden.\n61","KD's developed for the Mississippi River have been demonstrated to be\ngeneric, and are transferable to other river systems, e.g., the Brazos.\nIt was demonstrated, by analysis of interstitial water, that rapid\nparticulate removal and burial of lead in sediments results in\nirreversible removal of it from the overlying water column. This is not\nthe case with cadmium and manganese since diagenetic processes in the\nsediment remobilize these metals and allow diffusion back into the\noverlying water.\nSuspended particulate matter (SPM) flux from rivers varies on an hourly\nand daily basis as well as on a seasonal one. This is controlled to a\nlarge degree by tidal forces, which also control whether the major escape\nof SPM is by surface flow or near-bottom flow.\nSPM not removed near the river mouth is removed from the water column by\nbiopackaging, i.e., ingestion by marine organisms and formation of fecal\npellets.\nPlans FY 1985\nTAP\nIn FY 1985, AOML activities conducted in the TAP program will be\ndependent upon NOS/OAD (National Ocean Service/Ocean Assessment Division)\ndecisions regarding proposals submitted to them. Present plans are centered\non three basic activities:\nConducting a second research cruise to the New York Bight area to study\nthe speciation of metals and effects of sewage sludge input on this\nspeciation when warm, stratified conditions exist and biological produc-\ntion is at or near maximum.\nContinue analysis of data and samples collected in the TAP program with\nthe goals of (1) conducting a statistical analysis of biological samples\nrelative to metal speciation, and (2) understanding the kinetics and\nbinding constants of natural metal-organic complexes and their relation-\nship to environmental variables such as temperature, light, and salinity.\nDeveloping biochemical methods for determining secondary productivity and\nthe effects of environmental changes in this productivity.\nP-PRIME\nNo further activity is planned in the P-PRIME program, owing to with-\ndrawal of NOS/OAD funding.\nMARINE OBSERVATION AND PREDICTION\nAOML research in marine observation and prediction is described within\nthree areas: (1) acoustical measurements of ocean currents, bottom topography\n62","for charting and navigation, particulate distribution and transport processes;\n(2) development of new techniques to observe atmosphere, ocean, and surface\nparameters and application of remote-sensing techniques to study the physical\nprocesses of importance to maritime interests of the United States; and (3)\nresearch into improvement of current vectors and sea-state maps using two\nCODAR (Coastal Ocean Dynamics Applications Radar) units deployed in the\nMiami/Fort Lauderdale, Fla., area as a fully developed operational system in\ncollaboration with the U.S. Coast Guard, the National Hurricane Center (NHC),\nand WPL.\nAccomplishments FY 1984\nACOUSTICAL MEASUREMENTS\nData from the Chesapeake Bay experiment were analyzed; successful trans-\nverse Doppler measurements of the vertical component of the flow field\nassociated with short-period internal waves were made. A theoretical\nexplanation of anomalous experimental measurements of the acoustic backscatter\nfrom sets of different diameter particulates was derived using the concept of\ntotal acoustic cross section.\nA cooperative program was established with elements of NOS to carry out\nthe research that is required to understand the complex interaction of sound,\nincluding its transmission and reflection, with the diverse types of bottoms\nencountered in U.S. coastal and near-coastal waters. Ultimately, improved\nnavigational charts and improved bottom topography and bottom-type maps will\nresult.\nTECHNIQUES DEVELOPMENT\nRecent emphasis has been on the effects of wave refraction by ocean\ncurrents and the growth of waves in complicated geometries. The fundamental\nlimiting factor to existing wave prediction models is the process of wave\nAOML\ngrowth for a strongly curving windfield such as a hurricane or severe winter\ncyclone. Such storms, moreover, annually claim many lives. Radar-derived\ndirectional wave spectra have been obtained, which reveal some new insight\ninto this process and suggest that most numerical models do not properly\npredict the direction and hence the height of waves for extreme conditions.\nThis implies that other types of ocean models that attempt to predict the\nmomentum transferred to the ocean by the atmosphere (storm surge models, for\nexample) may be significantly in error for storms that are outside the class\nof calibration storms.\nCODAR OPERATIONAL DEMONSTRATION\nDuring FY 1984, AOML has been working with the Coast Guard, NHC, and WPL\nfor the purpose of developing an operational demonstration of a two-unit CODAR\nobserving system in the Miami/Ft. Lauderdale area. The system would provide,\non a regional scale, in near real-time, observations of ocean surface currents\nand sea state. If shown to be operationally feasible, the system would be\n63","turned over to a planned NOS Ocean Service Center beginning in FY 1986.\nProgress during FY 1984 consisted primarily of planning and coordination\nactivities between the various groups that would be involved. The necessary\nequipment and personnel were all identified, and the site selection process\nwas initiated.\nPlans FY 1985\nACOUSTICAL MEASUREMENTS\nDeploy and operate a coherent transverse Doppler current measurement\nsystem at the Port of Miami in conjunction with the deployment of an\nAmetek-Straza Doppler current profiler by NOS personnel and with the Port\nof Miami circulation survey to be conducted by a contractor.\nUpgrade data analysis equipment and continue processing of data from\nprevious year experiments.\nContinue analysis of Chesapeake Bay experiment acoustical data.\nContinue development of estuarine and oceanic particulate and pollutant\ntransport models.\nConduct laboratory experiments on the acoustic cross section of naturally\noccurring sand grains as well as field experiments using high-frequency\nacoustics to measure sediment in the benthic boundary layer in\ncooperation with Canadian and University of Miami investigators.\nExplore the possibility of cooperation with NASA to utilize zero-g\nenvironment for scattering experiments to avoid problem of particle\nsettling in gravitational field.\nDevelop a model or models of echo formation from various bottom types.\nImplement these models on the AOML computer system.\nDesign an experimental program to provide data for model development and\nfor model validation.\nTECHNIQUES DEVELOPMENT\nHurricane imagery will be processed to yield two-dimensional wave spectra\nfor comparison with model hindcasts. Ice imagery will be processed to yield\nice concentrations and compared with in-situ results to determine tvpe sensi-\ntivity. Laser profilometer data will be processed to yield spectra of the\nroughness elements corresponding to the imagery.\nCODAR OPERATIONAL DEMONSTRATION\nAll WPL CODAR equipment will be transferred to AOML by the start of FY\n1985. Sufficient equipment exists to establish two shore stations and a data\n64","dissemination station at NHC. Additional equipment purchases are necessary\nfor the telecommunication links between stations and NHC, and for routine\nmaintenance. AOML will establish shore stations at the Navy site in Fort\nLauderdale, and at the Coast Guard site on Fisher Island. Data processed into\ncurrent vector maps will be disseminated by NHC, and development of sea-state\nmaps will begin at AOML.\nMARINE RESOURCES\nAOML conducts research in marine resources in two specific areas. One\nprogram studies the effects of venting of fluids within hydrothermal areas\nalong seafloor-spreading centers on the ocean environment. This research is\npart of the NOAA/VENTS program. The second consists of research as to envi-\nronmental controls on the year-class-strength of commercial U.S. fisheries.\nThis project is a lead-in effort to the developing NOAA Fisheries Oceanography\nCooperative Investigations (FOCI) initiative.\nAccomplishments FY 1984\nVENTS\nIn FY 1984, AOML spent considerable effort in a NOAA-wide task of\ndeveloping the NOAA/VENTS program. This included the development of relevant\nand testable hypotheses, devising means of testing them, and the definition\nand allocation of resources. This was done through AOML participation on the\nVENTS Council. As part of this effort, AOML defined a research program on\nslow-spreading hydrothermal centers designed to determine the quality and\nquantity of hydrothermal venting and its effect on ocean systems. A major,\nmultidisciplinary cruise was conducted to a representative section of a slow-\nspreading ridge (the Mid-Atlantic Ridge between 11°N and 26°N). By use of\ngeophysical models developed during a cruise, in FY 1982, four sites of\nhydrothermal venting were confirmed by use of chemical indicators in the water\ncolumn, near-bottom temperature measurements, hydrothermal constituents in\nAOML\nsediments, and hydrothermal minerals on the seafloor.\nIn addition, previous work conducted in the TAG (Trans-Atlantic Geo-\ntraverse) hydrothermal area at 26°N was synthesized and published, including\nclear evidence that episodic \"black smoker\" type hydrothermal venting has been\noccurring in this area at a frequency of approximately every 10,000 years for\nthe past million years.\nFISHERIES-OCEANOGRAPHY RESEARCH\nAOML is conducting research with a goal of understanding environmental\ncontrols on the year-class-strength of commercial fisheries so that such\ncontrol can be predicted, thus allowing (1) better management of these\nfisheries and (2) better investment planning for their exploitation. Present\nefforts are directed to understanding how offshore (shelf) fronts control the\nfeeding success of larval fish and thus, their survival and postlarval\nrecruitment in estuaries where juvenile stages develop. The hypothesis being\n65","tested is that a major control on the feeding success of larval menhaden and\nshrimp is the position, timing, and quality of offshore oceanic fronts such as\nthose at the Mississippi River outflow to the Gulf of Mexico and at the Gulf\nStream boundary with southeast U.S. shelf waters. In FY 1984, AOML research,\nconducted cooperatively with the Southeast Fisheries Center, documented a\nrelationship between growth of Gulf menhaden, spot, and croaker larvae and the\ndistribution of their food along hydrographic fronts at the Mississippi\noutflow. In addition, a biochemical tool (nucleic acid analysis) was\nperfected for determining the potential protein growth rate of larval fish,\nallowing us to establish the suitability of specific ocean fronts as feeding\nenvironments for larval fish.\nPlans FY 1985\nVENTS\nWork will continue on determining the quality and quantity of hydro-\nthermal venting along slow-spreading centers and the effect of venting on the\nocean environment. In FY 1985 a second cruise will be conducted along the\n11°N to 26°N section of the Mid-Atlantic Ridge to complete analysis of\nhydrothermal activity at the four sites positively identified during the\nFY-1984 cruise. In addition, a cruise will also be conducted to the Gorda\nRidge off the west coast of the United States. The ridge is another represen-\ntative slow-spreading ridge completely within the U.S. Exclusive Economic\nZone. This cruise will be dedicated to developing geophysical criteria for\nlocating hydrothermal activity on that ridge as well as for searching for\ngeochemical signatures resulting from such activity.\nFISHERIES-OCEANOGRAPHY RESEARCH\nIn FY 1985, AOML will continue to work cooperatively with SEFC to deter-\nmine the environmental controls at oceanic fronts on feeding success and\nsurvival of larval fish. The FY -1985 effort will be focused on fronts created\nat the Mississippi outflow to the Gulf of Mexico and their effect on the\nfeeding success of brown shrimp and Gulf menhaden larvae. A cooperative AOML-\nSEFC cruise will be conducted to the outflow area aboard the NOAA Ship\nResearcher in May-June 1985.\nAIR QUALITY\nAOML conducts research on air quality in two specific areas: (1) mature\noceanic sources of acid rain precursors, and (2) radiatively important trace\nsubstances in the atmosphere. The latter is a lead-in effort to the\ndeveloping NOAA/RITS (Radioactively Important Trace Species) program.\n66","Accomplishments FY 1984\nACID RAIN\nIn FY 1984, AOML continued research on oceanic sources of compounds that\nare injected into the troposphere and react to form chemical species that\nproduce acid rain. AOML's work was conducted on the premise that the produc-\ntion of these compounds is controlled by biological processes in the photic\nzone. The existence of a significant concentration of 1-alkenes in the upper\nocean was documented, and it was further demonstrated that the transfer of\nthese compounds across the air-sea interface, and subsequent oxidation, could\naccount for the formic acid anomaly existent in the troposphere. This process\nis a significant contributor to the acidity of rain in remote regions. A\njoint ship-aircraft sampling program was completed in the equatorial Pacific\nalong 150°W between 10°N and 10°S to study both biological and photochemical\nprocesses as they relate to the distribution of atmospheric gases. During\nthis cruise a distinct vertical distribution in the turnover rates of sulfur-\ncontaining amino acids in the water column was documented. In addition, the\nexistence of a diel cycle in these turnover rates was confirmed. These\nfindings are important to understanding the biological processes that release\nsulfur-containing acid rain precursors, such as dimethyl sulfide and dimethyl\nsulfone, to the troposphere. In addition, AOML identified a maximum in the\nconcentration of ammonia in precipitation in the equatorial Pacific Ocean.\nRITS\nAOML research in oceanic sources of radiatively important trace sub-\nstances in the atmosphere is conducted as a lead-in effort to the developing\nNOAA/RITS program. Research in FY 1984 was conducted as a piggy back opera-\ntion to AOML Acid Rain research. Part of this effort was an investigation of\nthe existence of volatile components in the upper ocean and lower troposphere\nthat are infrared absorbers (or which, when transferred to the lower\ntroposphere from the ocean, could react to form such absorbers). A large\nsuite of volatile samples was collected during the AOML joint shipaircraft\nequatorial Pacific study along 150°W, and analysis is proceeding. As part\nof this cruise effort, AOML also confirmed the existence of an ozone minimum\nAOML\nin the equatorial Pacific in May-June 1984.\nPlans FY 1985\nACID RAIN\nAOML will continue to conduct research on oceanic sources of compounds\ncontrolling the acidity of rain. A significant part of the FY-1985 effort\nwill consist of analysis of samples on hand from the 1984 effort and synthesis\nof the results of research conducted to date. AOML will also conduct a cruise\nto the trade wind region of the Atlantic to study the interaction of conti-\nnentally derived tropospheric species with trace gases produced in the upper\nocean of the subtropical North Atlantic Ocean.\n67","RITS\nDuring FY 1985, AOML will continue to conduct lead-in research to the\nNOAA/RITS program. A major emphasis will be placed on analyzing volatile\nsamples collected in the upper ocean during the FY-1984 cruise and correlating\ntheir chemistry with that of tropospheric samples collected during the same\noperation. Similar studies will be conducted during the AOML Acid Rain\nresearch cruise to the subtropical North Atlantic in FY 1985.\n68","PACIFIC MARINE ENVIRONMENTAL LABORATORY\nEddie Bernard\nSeattle, Washington\nDirector\nDirector\nO/P\nDep. Director\nCooperative\nESG\nCRP WRP PROFS WMP\nInstitutes\nAOML\nPMEL\nGLERL\nGFDL\nNSSL\nWPL\nARL\nAL\nSEL\nThe Pacific Marine Environmental Laboratory (PMEL) is a mission-oriented\ngovernment laboratory that conducts interdisciplinary scientific investigations\nin oceanography, marine meteorology, and related subjects. The current PMEL\nprograms focus on climate, marine environmental assessment, marine observation\nand prediction, and marine resources. Studies are conducted to better under-\nstand the complex physical and geochemical processes that determine the extent\nof human impact on the marine environment; to define the forcing functions and\nthe processes driving ocean circulation and the global climate system; and to\nimprove environmental forecasting capabilities and other supporting services\nfor marine commerce and fisheries. Products of PMEL's research are environ-\nmental information and predictive models that are disseminated by means of\nscientific papers, technical reports, and presentations at scientific and\npublic gatherings.\nPMEL\nTwo cooperative institutes, the Joint Institute for Study of Atmosphere\nand Ocean (JISAO) and the Joint Institute for Marine and Atmospheric Research\n(JIMAR), established between NOAA and the University of Washington and Hawaii,\nrespectively, provide a bridge between the academic community and PMEL scien-\ntists working in climate dynamics, environmental chemistry, tsunamis, and\nestuarine processes.\nCLIMATE RESEARCH\nDuring recent years there has been an increasing awareness of the impact\nof short- and long-term climatic changes on resource systems, particularly\nfood and energy, and conversely, a concern about the impact of technology and\npopulation growth on world climate. When the National Climate Program Act was\n69","passed in 1978, NOAA became the lead agency for U.S. research in climate\ndynamics. PMEL scientists have been heavily involved in the formulation and\nimplementation of the NOAA Ocean Climate Program.\nTo predict climatic change, it is necessary to understand the processes\nof heat, moisture, and momentum exchange between the ocean and atmosphere, as\nwell as the large-scale transport of heat by the atmosphere and ocean. The\nocean climate research program investigates the problem in studies of both\nlocal (small-scale) and basin wide (large-scale) ocean dynamics and the coupled\nocean-atmosphere circulation. Laboratory participation in multi-institutional\nfield experiments has established the groundwork for present efforts in two\nnational climate programs: Equatorial Pacific Ocean Climate Studies (EPOCS)\nand Tropical Oceans and Global Atmosphere (TOGA) These studies are testing\nthe hypotheses that ocean surface temperature anomalies in equatorial regions\nhave a pronounced effect on atmospheric circulation in both temperate and\nequatorial latitudes. A major research goal is to determine the relative\nimportance of the physical mechanisms that generate anomalies in sea surface\ntemperature distributions in the equatorial ocean.\nHeat transport by major western boundary currents, the Gulf Stream and\nKuroshio in the Northern Hemisphere, are also postulated to have an important\nimpact on world climate. During 1984 a PMEL study focused on the Florida\nCurrent as part of the Subtropical Atlantic Climate Studies (STACS).\nPMEL is also conducting two unique marine-chemistry research activities\nfor NOAA under the National Climate Program. These activities relate to the\nocean's behavior as a sink for atmospheric carbon dioxide, which has been\nsteadily increasing over the past century. One project measures the flux of\nhuman-made fluorocarbons into the ocean in order to trace gaseous diffusion\nacross the ocean-atmosphere boundary. The other project is examining the\nrole of biologically produced, particulate calcium carbonate as an absorber of\ncarbon dioxide at high latitudes. Together these studies will help determine\nthe potential of the oceans for absorbing carbon dioxide.\nAccomplishments FY 1984\nEQUATORIAL DYNAMICS\nEl Nino/Southern Oscillation (ENSO)\nDuring certain years, large interannual changes occur in the heat content\nof the upper layer of the tropical Pacific. Associated with these oceanic\nchanges (anomalies of 2° to 5°C in sea-surface temperature are observed) are\nperturbations in the atmospheric circulation which appear to initiate the\nocean changes. After the near-surface heat content of the ocean is modified,\nfurther atmospheric perturbations are generated by process of air interaction\nwith the ocean. The phenomenon of mutual interaction of the tropical ocean\nwith the global atmosphere on interannual time scales has been termed the E1\nNiño/Southern Oscillation (ENSO) problem, and is the main focus of the NOAA-\nsponsored EPOCS program.\n70","Research at PMEL on the ENSO problem is coordinated through the EPOCS\nprogram. During the past year our field program continued deep sea current\nmoorings; measurements of wind, current, and temperature at the Equator in the\neastern Pacific; north-south transequatorial sections to measure velocity,\ntemperature, salinity, and dissolved oxygen across the major components of the\ncurrent system in the eastern Pacific; and time series of sea level at the\nGalapagos Islands. Ship-of-opportunity subsurface and surface temperature\ndata were also analyzed.\nEquatorial Dynamics During 1982-83 ENSO Event\nThe 1982-83 ENSO episode presented an excellent opportunity to study\nseveral aspects of the heating and cooling cycle of the upper equatorial\nocean. Shipboard and moored temperature and current meter measurements have\nbeen used to describe and document the eastward movement of heat in the upper\nwater column to a depth of 200 m. The onset of the 1982-83 El Niño was\nobserved in June 1982 for locations west of the dateline, in July for\nlocations in the central Pacific such as 160°W, in August at our mooring sites\n(0°, 95°W, and 0°, 109°30'W), and in September at the coast of Peru. From\nmid-August 1982 to mid-December, the heat content rose steadily in the eastern\nPacific. Maximum values occurred 1-2 weeks earlier at 109°30'W than at 95°W.\nDuring September and October, the heat content increased very rapidly. At\n95°W the time rate of change of heat from mid-August to mid-December was 5-10\ntimes larger than could be accounted for by surface heat flux, assuming the\nnet surface heating during 1982-83 was not much different than during the\n1972-73 El Niño. Between mid-December 1982 and 1 March 1983, there was a\nrapid drop in heat content with the onset of subsurface cooling and, conse-\nquently, the reestablishment of the thermocline at its former depth. This was\nassociated with the deceleration of the eastward currents and the onset of\nwestward flow at depths where the equatorial undercurrent normally occurs.\nAlthough a decrease in the heat content at 109°30'W continued after 1 March\n1983, the upper ocean heat content at 95°W increased again, reaching a second-\nary maximum around 1 June. This maximum was associated with a sea level rise\nat the Galapagos Islands.\nSome of the large-scale heat and salinity changes that occurred during\nthe 1982-83 El Niño may be attributed to local air-sea interaction (e.g.,\nPMEL\nlowering of surface salinity by precipitation) and others may be attributed to\na combination of local air-s interaction and advection. A program of\nsampling of surface salinity and subsurface temperature (by XBT's) has been\ncarried out from merchant ships of opportunity. Low salinities observed near\nthe Equator along a trackline between 20°N, 158°W, and 20°S, 180°W, were\nprimarily the result of the greatly increased rainfall in the central Pacific,\nrelated to eastward movement of the warm water and associated atmospheric\nconvection. Effects of lower salinities on the mass field accounts for about\none-third of the total dynamic height change observed at island stations.\nAdditional merchant ship sampling was done along lines that cross the\nEquator at 160°E and 100°W. These measurements showed that a drastic shift in\nthe mass field occurred, resulting in the appearance of a westward pressure\ngradient between the western and central Pacific from mid-1982 to the beginning\nof 1983. For a 5-month period the dynamic height of the sea surface was\n71","either higher in the east than in the west or roughly equal. These time\nchanges of the mass field represent a change in the forces that drive the\ncurrents at the Equator.\nSince 1979 PMEL has maintained an array of bottom-moored pressure gauges\nat the Galapagos Islands to study low-frequency equatorial waves. These\ngauges, combined with others in the equatorial wave guide, have provided a\ncontinuous record of the onset and demise of the large (~0.5 sea level\nperturbations associated with the 1982-83 ENSO event. The timing of this\nonset was demonstrated by gauges on Galapagos (0°3'S, 91°28'W) and Jarvis\n(0°23'S, 160°W) Islands, which showed the latter leading by 28 days. The\n28-day travel time corresponds to an eastward phase speed of 3.2 m s-1 , which\nis near that expected for a first vertical mode equatorial Kelvin wave. Cross\ncorrelation of these two sea level records showed significant correlation\npeaks corresponding to the 28-day delay and a 56-day delay. This latter peak\nwas identified as a second vertical mode Kelvin wave. This identification was\nsupported by demonstrating that a combination of first- and second-mode waves\nin phase at Jarvis would, through modal dispersion, lead to the slower sea\nlevel rise time observed at Galapagos. A final significant, positive cross\ncorrelation peak between Jarvis and Galapagos was observed, Galapagos leading\nJarvis by about 80 days (corresponding to a westward phase speed of 1 m s-1).\nThis peak was tentatively ascribed to a first vertical, first meridional mode\nequatorial Rossby wave. Both the second-mode Kelvin wave and the Rossby wave\nplay prominent roles in theories of equatorial ocean dynamics. PMEL's measure-\nments are the first evidence for these signals in the observational data.\nDynamical studies of the near-equatorial circulation suggest that small-\nscale turbulent mixing should play an important role in the momentum balance.\nAnalysis of horizontal-velocity shear and density data collected using the\nPMEL profiler TOPS (Total Ocean Profiling System) along 110°W from 10°N to 7°S\nwere used to study the variability of fine-scale Richardson Number (Ri)\nstatistics in the depth interval 150-900 m. In this regime, shear and strain\nare dominated by the fine-scale rather than the mean fields. Results showed\nthat the extraequatorial band (4°-10°N) exhibited shear and strain spectra as\nwell as Ri statistics that were consistent with middle-latitude internal-wave\nmodel predictions. However, near the Equator an enhancement of shear and\nstrain variance is found along with an accompanying increase in the occurrence\nof Ri less than one-fourth, suggesting large regions of active mixing.\nMiddle-latitude internal wave models cannot explain this enhancement; the\ninclusion of equatorial trapped waves or other processes is required.\nSatellite imagery has shown that during part of the year the sea surface\ntemperature (SST) front between colder water at the Equator and warmer water\nto the north is wavelike in structure. These fluctuations in the position of\nthe temperature front have wavelengths of approximately 1,000 km and propagate\nwestward at about 40 km/day. Surface temperatures in vertical sections of\ntemperature drawn from the XBT data are in quantitative agreement with satel-\nlite SST's along the Equator. These XBT sections show a phase shift to the\nwest. If this pattern extended far enough off the Equator, it would indicate\na geostrophically induced equatorward flux of heat. This result agrees with\nheat flux calculations from drifting buoys. These calculations have shown\nthat eddies, which are located in the trough of the waves and translate\nwestward with the wave phase, effect an equatorward transport of heat that\namounts to about two-thirds the poleward heat transport of the divergent Ekman\ntransport.\n72","Statistical Analysis of Historical Data\nGlobal marine data sets recently have been compiled from ships' deck\nlogs. These data sets have been examined for evidence of long-term, large-\nscale climate changes as reflected in fields such as sea surface temperature\nand sea level pressure. However, there is considerable uncertainty about the\nreliability of results based on these historical data sets, since the ship-of-\nopportunity observations contain both random and systematic errors and since\nthe observations are generally sparse in time and space. Rigorous statistical\ntechniques have been developed for analyzing data sets back to the level of\nindividual ship observations. Appropriate autoregressive models were deter-\nmined for the daily, monthly, and annual time scales. These models are used\nto generate artificial, but realistic, time series of daily values of SST and\nsea level pressure. These artificial time series correctly reproduce the\nstatistical properties of the actual data. By use of Monte Carlo techniques,\ntime series can be randomly sampled and probability distributions constructed\nof the sampling errors as a function of location and averaging period. These\ndistributions can then be used to place confidence limits on climatic signals.\nEl Niño Effects Off the Pacific Northwest Coast\nA compilation of sea levels showed that El Niño events of 1941, 1958, and\n1982 had large coastal effects off Washington and British Columbia. Signifi-\ncant positive temperature anomalies were observed to extend more than 200 km\noffshore and to depths of about 500 m. The effects at middle latitudes\n(47°-48°N) appear to have been generally similar for the 1941, 1957-58, and\n1982-83 El Niños. The sea-surface temperature anomalies were larger in 1958\nthan in 1983; however, the 1958 event seemed to decay more quickly. The\noffshore extent of the anomalies was about the same in all three events.\nUnusually warm water extended out to about 127°W, more than 200 km and about\nhalf the extent off California. The temperature sections strongly suggested\nnorthward flow along the continental slope in February 1958, near the peak of\nthe El Niño, implying a southern source of water. The vertical distributions\n(to ~500 m) show that a relatively large volume of water was involved.\nSTACS\nPMEL\nCross Stream Voltage Measurements of Florida Current Transport\nMeasurement of the voltage difference across the Florida Current from\nJupiter Inlet, Fla., to Settlement Point, Grand Bahama Island, utilizing sub-\nmarine telephone cables has been established as a useful method for accurately\nand continuously recording the fluctuations in transport. The cable voltages\nare converted to transport units by multiplying with a linear calibration\nfactor found by comparing the cable voltage data with transport values from\nvelocity-profiling data. The rms difference between cable and profiling data\nwas small (less than 3% of the mean).\nThe Florida cable consists of an insulated copper wire surrounded by\nsteel armor. One problem encountered is that sudden voltage changes have been\nobserved since 1983 that are due to random switching of the cable-to-seawater\nground contact during normal operation of the cable (from mainly copper to\nmainly armor). An analysis technique has been developed that effectively\n73","removes these sudden jumps by least-squares fitting a Heaviside function to\nlocally detrended series. Results indicate that the cable can be used, pro-\nvided the seawater contact at Settlement Point is the Ag-AgCl electrode in the\nseawater basement of the cable block house. Eliminating all the offsets would\nrequire repairing or replacing the cable.\nTelephone Submarine Cables\nTelephone submarine cables cover many parts of the ocean and are partic-\nularly well suited to observe western boundary currents. Telephone cables,\nhowever, contain repeaters that are used to amplify the voice signal and are\npowered by a shore-based constant current source. The return path for d.c.\npower current is through seawater via the ground points near the current source\nand at the far end of the cable. The d.c current flowing through the repeater\ncauses a constant voltage drop across each repeater. Measurements of the\nvoltage difference between the ground points of telephone cables contain three\nparts: (1) the voltage difference caused by ocean currents; (2) the voltage\ncaused by geomagnetic variations; (3) the voltage caused by the sum of the\nvoltage drops across all repeaters. The time-dependent part will be due to\nrepeater noise caused by variations in the d.c. current source, temperature\neffects on the repeaters, and aging of the repeaters. Preliminary analysis\nhas shown that for transatlantic submarine cables the net transport will vanish\nand the cable voltages can be used to measure ambient water temperature. For\ntypical voltage measurements a cable could sense mean sea floor temperature\nfluctuations as small as 0.0001°C. A time history of such fluctuations would\nbe useful for ocean climatic studies.\nCARBON DIOXIDE RESEARCH\nSince about 1850, human activities, including the burning of fossil fuels\nand deforestation, have resulted in an increased amount of CO2 in the atmos-\nphere, from somewhere around 270 ppm to a little more than 340 ppm. This\nphenomenon is thought to affect the Earth's radiation balance and thereby\nincrease the Earth's temperature. Major repositories for fossil-fuel-derived\nCO2 are terrestrial vegetation, the atmosphere, and the oceans; each of the\nlast two contains close to 50% of the excess according to recent estimates.\nThe buildup rate of atmospheric CO2 depends on the oceanic uptake rate of\ncarbon dioxide, which is controlled by diffusive and convective mixing pro-\ncesses, by sinking and decomposition of biogenic particulates, and by air-sea\nexchange rates.\nBecause the oceans can act both as a source and as a sink for atmospheric\ncarbon dioxide (particularly in upwelling and downwelling areas) PMEL scien-\ntists conducted an interdisciplinary study of the dynamics of the carbon di-\noxide system in the surface and intermediate waters of the central South\nPacific during FY 1984. The purpose of these investigations was to study the\ndynamics of the CO2 system and gas exchange along meridional transects that\ninclude major upwelling and downwelling regions of the South Pacific.\nDuring February through May, two meridional sections were made of total\ncarbon dioxide, pCO2, alkalinity, freons, suspended matter, calcium, salinity,\ntemperature, oxygen, and nutrients in the central South Pacific. In addition,\n74","atmospheric and surface ocean carbon dioxide measurements were made in coopera-\ntion with scientists from GMCC. The preliminary data indicated a significant\nmeridional gradient of seawater pCO2 concentrations along the 150°W transect.\nMaximum supersaturation occurred near the Equator and just north of the sub-\ntropical convergence. The equatorial pCO2 concentrations were similar to\nvalues obtained during the pre-El Niño 1979-80 FGGE expeditions, although\nbroad regions of anomalously warm surface water and high pCO2 concentrations\nwere still encountered in south equatorial latitudes. These results provide\nadditional evidence that the equatorial zone near 150°W has, for the most\npart, returned to pre-El Niño conditions and upwelling-induced supersatura-\ntions are prevalent from about 6°N to 4°S. The atmospheric data also show\npCO2 enrichments in the region between 15°N and 12°S, suggesting that the\nsupersaturated water is releasing significant amounts of CO2 to the atmosphere.\nThe results of the freon measurements clearly demonstrate their\nusefulness as a conservative tracer of upwelling processes in the equatorial\nregion. At 10°N, low-freon water (<0.2 pmoles 1-1) rises to within 200 m of\nthe surface. This feature coincides roughly with the 26.5 sigma-t surface.\nThis vertical displacement is the result of divergence along the north\nequatorial current. Near the Equator, a doming of the freon contours occurs\nas a result of the Ekman divergence. A subsurface freon maximum occurs south\nof 2°S, between 50 and 150 m. This freon maximum is associated with a\nsalinity maximum developed by the subsurface geostrophic flow toward the\nEquator. Farther to the south the freon isolines slope downward, coinciding\nwith the deepening thermocline. These results indicate that the general\npatterns of the freon distributions closely follow water mass movements in the\nequatorial zone and, therefore, are an excellent tracer of the dynamic\nprocesses occurring along the Equator.\nPlans FY 1985\nHAZARDOUS WAVES\nThe field program launched in 1983 to study the processes affecting heat\ncontent of the upper layer of the ocean along the Equator between 140°W\nand 110°W will be continued. This program will involve deep-sea moorings\nPMEL\nwith subsurface current meters and thermistors, measurement of surface\nwinds and air temperature, and profiling measurements of temperature,\nsalinity, and velocity (TOPS and Ametek-Straza Doppler-shift acoustic\ncurrent profiler). This EPOCS program is coordinated with the Tropic\nHeat Program sponsored by the National Science Foundation.\nThe 6-year records of currents and temperature at 100°W (continuing this\nyear) and of sea level at the Galapagos (to be terminated this year) will\nbe analyzed for evidence of zonally propagating signals along the Equator\nas part of EPOCS.\nThe predictability of El Niño events will be studied, using statistical\nprocedures applied to updated historical sets. Dynamical models\npredicting E1 Niño events will be verified, using recently devised\ndata/model intercomparison theory.\n75","Additional satellite imagery will be processed and compared with ship,\ndrifting buoy, and mooring data to investigate equatorial long wave\ndynamics. The effect of the presence or absence of long waves on the\nlateral fluxes of heat and momentum near the Equator will be examined.\nIn addition, special effort will be made to process the satellite data to\ncompute SST's in the equatorial Pacific from April to November 1982 in\norder to describe accurately the onset of the El Niño.\nThe merchant-ship-of-opportunity data set will be analyzed further to\ndetermine the vertical and horizontal structure of the major changes in\nthe thermal and dynamic height field during the 1982-83 event.\nComparisons between ocean numerical models and the thermal data will be\ncarried out to provide model verification.\nAn ocean numerical modeling effort will be undertaken in support of the\nEPOCS and TOGA programs. FY 1985 will see the acquisition of computer\nequipment, installation of a variety of numerical ocean models, and the\nbeginning of a large-scale upper ocean and lower atmosphere data analysis\neffort.\nSTACS\nThe collecting and analyzing of cable voltage from Florida Straits will\ncontinue. An effort will begin to turn operations over to NOS. Active\nsubmarine telephone cables will be tested for voltage and temperature\nmeasurements, and electromagnetic modeling of the Florida Current will be\npursued. Time domain analysis for electromagnetic response functions will be\nused to remove geomagnetic noise.\nCARBON DIOXIDE RESEARCH\nInitiate an oceanic CO2 monitoring program in the North Pacific.\nComplete development of the pCO2 sampling system.\nMARINE ENVIRONMENTAL ASSESSMENT\nMarine environmental assessment at PMEL emphasizes understanding the\ncomplex physical and geochemical processess that ultimately determine the\nhealth of the marine system and its ability to assimilate pollutants. In-\ncluded in this area are studies of suspended-sediment transport and geo-\nchemistry, distributions of hydrocarbons and synthetic organics, coastal and\nestuarine circulation, theoretical modeling of pollutant transport processes,\nand a program in marine sources of acid rain. Although the geographic focus\nof these studies has been Pacific Northwest and Alaskan coastal and estuarine\nwaters, the scientific knowledge acquired and methodologies developed are\napplicable to other marine systems. Two major activities at PMEL are studies\nof the long-range fate of chronic pollutants in marine waters and oceanic\nprecursors to acid rain.\n76","Accomplishments FY 1984\nLONG-RANGE-EFFECTS RESEARCH\nIn response to the Marine Protection, Research and Sanctuaries Act of\n1982 and the National Ocean Pollution Research and Development and Monitoring\nPlanning Act of 1978, PMEL has addressed environmental concerns associated\nwith transport and marine disposal of municipal waste water and the reaction\nof marine systems to continuous influx of pollutants. Under the NOAA Long-\nRange-Effects Research Program, PMEL is examining the role of suspended par-\nticulates in transporting pollutants or in removing them from the marine\nsystem. In support of these studies researchers are investigating the mechan-\nisms by which heavy metals and organic pollutants adhere to particulates. As\nthese processes become better understood, we will be able to assess the\nlong-term effect of chronic, low-level input of pollutants into the marine\nsystem.\nStudies in the Puget Sound-Strait of Juan de Fuca system, under way for\nseveral years, are leading to a better understanding of Puget Sound's ability\nto accommodate pollutant inputs. Many pollutants adhere to and move with\nparticles, and ultimately are buried in the sound or transported out of the\nsound along with particles. The emphasis of much PMEL research, therefore,\nhas been particle transport and fate.\nPollutant Transport in the Water Column\nPollutants are derived from both natural and human sources, including\nriverine, atmospheric, municipal and industrial sewage discharge, and dredging\noperations. Mass balance calculations for many indicate that human sources\nexceed the natural sources and buildup in sediments occurs over decadal or\nlonger time scales. The assimilative capacity of an estuary is a function of\nthe individual pollutant's physiological effects on the indigenous marine\nlife, residence time in the estuary, biological availability and uptake, and\nthe physical and chemical transformations occurring in the water column and in\nthe sediments. During FY 1984, PMEL scientists have made significant advances\nin understanding of the physical and chemical processes controlling the\ndistribution and fates of toxic trace metals and hydrocarbons in the Puget\nPMEL\nSound Estuary.\nStudies of the transport of water and particles in the main basin of\nPuget Sound are important because they allow us to evaluate this estuary as\na\ntrap for dissolved pollutants as well as particle-borne pollutants and to\npredict the distribution of particulate deposition. Our present conceptual\nmodel of Puget Sound, based on extensive observations of water properties and\ncurrents, suggests that circulation plays a dominant role in the accumulation\nof pollutants. These observations indicate that about two-thirds of the sea- -\nward-flowing surface water does not continue out of the sound but rather is\nmixed downward into the deep water at the Admiralty Inlet entrance sill. Such\nmixing is typical of fjord-like estuaries with sills, often found in the North-\nwest and Alaska. This downward mixing and retention of surface water contrasts\nsharply with the circulation typical of coastal-plain estuaries (e.g., Chesa-\npeake Bay) where deep incoming water is mixed upward into the surface layer as\nthe surface layer leaves the estuary. Direct measurements of water transport\n77","over Admiralty Inlet and within the main basin provide one method of quantify-\ning this retention process. Current meter observations and model estimates\nindicate that wintertime transport landward across Admiralty Inlet is only\none-half to two-thirds of the landward transport within the main basin, thus\nsupporting the refluxing concept.\nA firm mathematical foundation for the concept and consequences of re-\nfluxing has been developed. Refluxing between the seaward-flowing surface\nlayer and the landward-flowing deep layer of a reach leads to the build-up of\npollutants, which would not occur in the classic \"conveyor-belt\" view of fjord\ncirculation. A mathematical model applied to Puget Sound reveals that\nconservative pollutants are broadcast throughout the system, reaching signif-\nicant levels landward as well as seaward of their site of introduction. This\nmodel provides a tool to study the effects of present and proposed pollutant\ninputs on a basin-wide scale.\nCross-channel variability of axial currents at a location in the southern\npart of the main basin of Puget Sound was studied using 21 current meters\non\nsix moorings across East Passage in March-April 1983. Mass transport calcula-\ntions show a net up-estuary flux of 22,000 m 3 s-1 through East Passage. Flow\nin this part of Puget Sound is geographically controlled, and the net flow is\nclockwise around Vashon Island. At subtidal time scales, three circulation\nmodes were evident during the 31-day period of observation: (1) an out-estuary\nwind-driven flow in the near surface (upper 10 m), (2) a near-bottom layer\n(150-200 m) dominated by density currents that propagate up-estuary after\ngeneration at the entrance sill to Puget Sound, and (3) an intermediate layer\n(25-75 m) modulated at fortnightly intervals by nonlinear mixed tides.\nIn the main basin of Puget Sound, primary production and the\nconcentration of phytoplankton pigments in euphotic zone suspended matter vary\nsharply on weekly scales. These variations create a natural tracer for\nfollowing the transport of particulate matter out of the surface waters.\nWeekly concentration of pigments in the sediment trap material quantitatively\nfollowed the pigment concentration in the euphotic zone suspended matter.\nSuch a coupling indicates a rapid vertical transfer of surface-originating\nparticles by organic aggregates. The concentration of carbon in the flux,\nhowever, varied on a broad seasonal scale after smoothing of short-term\nvariations in production. The relative stability of the carbon flux arises\nfrom at least two sources: (1) a balance between terrestrial sources of carbon\nduring the high-runoff winter season and in-situ primary production in spring\nand summer, and (2) cycling of carbon through the zooplankton population.\nThe carbon delivered to the basin floor as measured by settling particles\ncaptured in the sediment traps can account for only about one-third of the\ncarbon utilized by benthic oxygen uptake and sediment burial. Additional\ntransport pathways are important. Field and theoretical investigations into\nthis process suggest that the annual mass of particles delivered to the deep\nwater by refluxing is comparable with that delivered by settling.\nThe relative trapping efficiency of the various metals by the sediments\nis largely dependent upon scavenging of trace metals by particulate materials\nsuspended in the water column and their subsequent deposition. From a 2-year\nstudy of trace metal fluxes in the main basin of the sound, PMEL scientists\nhave shown that scavenging by hydrous oxide and organic phases causes rapid\n78","uptake and sedimentation of several trace metals. For example, our mass bal-\nance calculations indicate that of the total amount of lead and copper entering\nPuget Sound, more than 90% is retained in the underlying sediments. Hence,\nthe scavenging processes by particulates provide a most efficient mechanism\nfor retaining toxic metals within the estuary.\nA new way of estimating the settling velocity spectrum of wastewater\neffluent has been developed. Previously available methods are inaccurate\nbecause the settling column experiments must be run at particle concentrations\nat which particle coagulation is known to occur. In this new method, particles\nat very low initial concentrations settle to their isopycnic levels in a\nlinear-density stratified column. Particle size distributions are determined\nby Coulter Counter from drawn samples. By using this method, the wet density\nand size distribution of particles in a sample from a wastewater treatment\nplant were measured in the 1.0-1.4 g cm 3 density and 1.0-64-um size\nranges.\nSupplementary measurements of size and density beyond these ranges provided\nsufficient coverage to construct a composite settling velocity distribution.\nThe method is believed to provide results free of flocculation effects because\nthe measurements may be made on samples at low initial concentrations\n(<10 mg 1-1).\nBottom Boundary Layer Processes and Pollutant Accumulation\nThe bottom boundary layer, the region of the water column from the sedi-\nment surface to several tens of meters above, plays an important role in the\nvertical distributions and the horizontal transport of particles. Processes\nwithin the boundary layer help determine the areal extent and patterns of\ncontaminants in the water and sediment column and the extent and duration of\nexposure of biota to contaminants.\nParticulate-borne pollutants in estuaries are often resuspended from the\nbottom and transported by tidal and other currents. Predicting how far such\npollutants are transported and where they are deposited permanently requires\na\ndetailed understanding of the processes at work in the bottom boundary layer.\nA high-resolution model for the unstratified bottom boundary layer is\nbeing developed at PMEL to predict profiles of currents, bottom stress, and\nPMEL\nturbulent diffusivity needed in studies of sediment resuspension and transport.\nThe model has been calibrated with observed tidal currents in Puget Sound and\nby comparison with analytical theory.\nA comprehensive review was completed on the tides and tidal currents in\nthe Puget Sound region which brings together in one publication knowledge from\na host of scattered and largely unpublished sources as well as new observations\ntaken by scientists at PMEL. The study shows that the general distributions\nof the tides and tidal currents are known but that the tidal dynamics and the\nsmaller-scale tidal features need to be studied further before the tidal\nregime is understood in detail. This work provides essential information for\nthe calibration of tide models for Puget Sound.\nThe first estimates for an in-situ erosion rate of fine-grained sediment\nin a marine environment have been made using an advection-diffusion model\ndeveloped at PMEL that was tuned to observations of time-dependent currents\nand sediment concentration made near the bottom of Puget Sound. Using a power\n79","law form for the erosion rate as a function of bottom stress, the erosion rate\nwas found to depend on the fourth power of the bottom stress. The power law\nalso fits results from laboratory studies. The rapid increase in resuspension\nwith increasing bottom stress indicates that the stress must be modeled accur-\nately to give realistic predictions of sediment transport. A number of bound-\nary layer models have been developed at PMEL to study and predict the behavior\nof suspended sediment, bottom stress, and turbulence in the presence of tidal\nand other time-dependent currents. An active field program is being carried\nout in connection with the modeling effort. This boundary layer research will\nprovide bulk formulas for use in regional models of sediment transport.\nThe high-resolution boundary layer model has been adapted to shallow\nflume conditions and extended to include suspended sediment. Predictions of\nsediment transport for different flow conditions match observations and give\nadditional evidence for the power law form of the erosion rate. One result of\nthis work is that there does not appear to be a critical stress for fine-\ngrained sediment below which the sediment is not resuspended. Even when the\ncurrents are small, some resuspension and transport are occurring.\nThe major particulate hydrocarbon transport processes appear to be rapid\nvertical transport through the water column and resuspension and lateral\ntransport in the bottom nepheloid layer. The hydrocarbons are ultimately\ntrapped in the fine-grained bottom sediments of the main basin. The sediments\nrecord the changing inputs during the past century. Hydrocarbon\nconcentrations from sediment cores increase since the 1900's, reflecting the\nindustrialization and urbanization of the area.\nRecent analysis of 210-Pb and 137-Cs profiles from cores taken to greater\ndepths in the main basin, with a coring device that minimizes core distortion,\nshows that the bottom material is accumulating at rates from 0.49 g cm-2 yr-\nto 1.12 g cm-2 yr-1. These rates indicate that the surface layer, which is\nsubject to bioturbation, can be as thick as 35 cm, suggesting that at some\nlocations the bulk of pollutants dating as far back as the early 1960's is\nstill being actively mixed in the surface layer and is still accessible to the\nbiota. Though these sedimentation rates are less than one-third those of the\nlonger term rates for sedimentation in Puget Sound based on geophysical data,\nthey are reasonable in light of current knowledge of volumes of recent sediment\ninput from riverine and shoreline sources.\nThe overall goal of the bottom boundary layer work is to quantify the\npatterns and redistribution processes for contaminants. In the past year, an\nintegration of previous work was continued with the development of a horizontal\ntransport and deposition-pattern model. The early results show that channel\nwidth variations will be reflected in along-channel sediment deposition rates\nand suggest that the input of sediment to the main basin of Puget Sound from\nthe side slopes is large.\nACID RAIN RESEARCH\nThe ocean is a major source of sulfur to the atmosphere. Plankton in the\nocean's photic zone produce dimethylsulfide, a reduced organic sulfur\ncompound, which diffuses from the surface waters into the atmosphere. In\nrecent years there has been increasing interest in quantifying this sulfur\nsource. This interest has developed from concern over acid rain and the\n80","influence of marine and terrestrial sources of organic sulfur on the chemistry\nof precipitation. These data are necessary to assess the significance of\nanthropogenic sulfur emmissions. With prevailing westerly winds, the west\ncoast of the United States is particularly susceptible to oceanic sulfur\nsources. There are many areas in the Pacific Northwest that are ecologically\nsensitive and have a very low buffering capacity for acidic precipitation.\nPMEL has conducted several cruises in the north Pacific Ocean to measure\nthe concentrations of dimethylsulfide. These concentrations are used to\ncalculate the oceanic input of sulfur to the atmosphere. The flux is\ncalculated using the stagnant film boundary layer model. Adopting a mean\nsurface concentration along the west coast of the United States of 50 ng S 1-1\nand a piston velocity of 2.6 m day-1, the mean flux of sulfur to the\natmosphere is 36 kg km- yr-1. If we assume an area along the coast extending\nout 1000 km to be the area affecting the coastal states, the net flux of\nsulfur to the continent is 0.065 Tg yr-1. This is approximately 20% of the\ncombined total anthropogenic emissions from California, Oregon, and\nWashington, and is equivalent to the input from Mount St. Helens during the\neruptive period of March 1980 to September 1982.\nPlans FY 1985\nLONG-RANGE-EFFECTS RESEARCH\nQuantify source and sink terms for hydrocarbons in Puget Sound.\nInvestigate hydrocarbon associations with suspended and settling\nparticulates.\nCalculate the time scales associated with the flushing of a conservative\nsubstance from a refluxing fjord system.\nCompare predicted concentrations from the Puget Sound Reflux Model with\nindependently measured tracer concentrations.\nAssess annual variations in flow and transport from the existing data\nPMEL\nbase and measure cross-channel variations at the site of the longest time\nseries in the northern part of the basin.\nExtend the boundary layer models to include the interactions of time-\ndependent currents, turbulence, suspended sediment, and trace metals in\nthe bottom boundary layer.\nDevelop simple transport models of suspended sediment to predict erosion\nand deposition patterns for selected sections of Puget Sound.\nDevelop models for density intrusions and their effects on sediment and\npollutant transport.\nQuantify recycling processes for trace metals from sediments.\nStudy trace metal uptake by and release from marine plankton.\n81","Use recently acquired data to look at small-scale variability in\nsedimentation rates and relate these to the hydraulic and erosional\nregimes.\nACID RAIN RESEARCH\nConduct additional cruises off the west coast of the United States to\nassess the seasonal variability of dimethylsulfide concentrations.\nCarry out laboratory studies to measure the solubility and diffusivity of\ndimethylsulfide in seawater.\nMARINE OBSERVATION AND PREDICTION\nMarine observation and prediction research is directed toward understand-\ning and improving the prediction of phenomena related to marine warning and\nforecasting services. Research subjects include sea-ice processes, hazardous\nwinds, hazardous waves, fisheries oceanography, and tsunami propagation and\nrun-up. PMEL scientists work closely with colleagues from operational service\ncomponents of NOAA, such as the Northwest Ocean Service Center and the Navy/\nNOAA Joint Ice Center. Studies of sea-ice processes are also applicable to\nNOAA's climate research. These studies of coastal meteorology, physical ocean-\nography, and sea-ice processes are carried out through a combination of field\nmeasurements, remote-sensing techniques, and numerical modeling.\nAccomplishments FY 1984\nRESEARCH\nMIZEX-West Experiment\nOver the past year, scientists from PMEL have completed analysis of data\nfrom several past experiments in the Bering Sea ice pack. Research results\nhave been used to implement the NOAA sea-ice forecasting model at the National\nMeteorological Center (NMC) and to plan future studies.\nMajor results are from the Marginal Ice Zone Experiment (MIZEX), which\ntook place in the southern Bering Sea in February 1983. The experiment was a\nmultidisciplinary, multi-institutional program that addressed a broad spectrum\nof physical processes related to the marginal ice zone. As part of this ex-\nperiment, PMEL placed an array of eight ARGOS-tracked transponders on the ice\nat 60.6°N, 170°W, on 10 February. The transponders were tracked westward and\nthen southward around St. Matthew Island until 28 February when the last\ntransponder broke out of the ice and ceased transmitting. These stations\nmeasured mean winds and temperatures every half hour at a height of 3 m, and\nmean ocean currents and temperature at a depth of 2 m under the ice. The\ntransponder tracks show that the array maintained its original shape over the\nentire period of 10-22 February in spite of a near collision with St. Matthew\nIsland, supporting the idea that ice-ice interaction was negligible. The wind\n82","factor, the ratio of ice speed to wind speed, and drift angle of the floe to\nthe right of the wind showed no discernible variation as a result of the\ntransponders' proximity to the island.\nThe two dominant forces that control ice motion in this region are the\nwind drag and the water drag. Surface winds and temperatures during MIZEX\nagreed well with synoptic scale weather patterns. Current directions were\nwell correlated with the wind directions and nearly colinear. The air and\nwater drag on the ice were computed by integrating momentum balance equation\nand substituting wind speeds, current velocities, and ice drift velocities\nmeasured on individual floes. For the southern Bering Sea, drag coefficients\nwere found to be .0030 for air referenced to a wind speed at 10 m, and .020\nfor water drag at -1.1 m. A similar air drag value was calculated from turbu-\nlence measurements made by the NOAA P-3 aircraft, suggesting that aircraft\noffer an excellent method of obtaining air drag coefficients for regional ice\ndrift models. During MIZEX it was also confirmed that wind acceleration at\nthe ice edge is a result of reduced friction because of fewer floes and baro-\nclinic forcing, as predicted by modeling studies.\nModeling of Sea Ice Drift\nA critical issue for modeling ice drift in the Bering Sea is to\nunderstand the influence of bathymetry on the wind drift of ice since most of\nthe ice-covered Bering Sea is less than 70 m deep. The free-drift equations\nfor ice motion, which assume momentum balance between air and water stress and\nthe Coriolis parameter, have been solved during this past year for ice floes\nin a shallow sea of neutral density stratification, typical of many high-\nlatitude continental shelves. Steady solutions for ice drift and current\nvelocity have been obtained as functions of wind stress, ice thickness, and\nwater depth. The ocean is modeled by second-order closure using the high-\nresolution boundary layer model developed at PMEL, which allows continuous\nsolutions from 5-m depth to deep water.\nThe solutions show that there is little dependence on water depth for\ndepths greater than 30 m, because turbulent mixing is a decreasing function of\nwater depth and offsets other influences of finite depth. However, for water\ndepths less than 30 m, ice velocities can change rapidly with wind speed and\nPMEL\nwater depth; and the presence of turbulence from tidal shear is very important\nfor coupling wind-driven ice drift to the bottom. For the deep-water limit,\nthe second-order closure solution confirms analytic solutions, used in the\nNOAA ice-forecasting model, that indicate an increase of 20% in the ratio of\nice speed to wind speed as the wind speed increases from 10 to 20 cm s-1.\nIce Extent Forecasting Model\nA model to forecast sea ice extent for the Bering Sea, developed at PMEL,\nwas operationally tested at NMC during the 1983-84 ice season. The model\nbalances ice advection and thermodynamic processes to determine a new ice edge\nlocation from forecasts of winds and air temperatures derived from the NMC\nspectral atmospheric forecast model. The experimental forecasts began in\nmid-December and were available in digital format to analysts at NMC and the\nJoint Ice Center (JIC) On 31 January the first experimental graphic product\nwas sent on the facsimile circuit to the NWS Alaska Region for evaluation by\n83","the Ocean Service Unit. Forecasts subsequently were sent to Alaska on\nTuesday, Thursday, and Saturday until 28 June when the Bering Sea became ice\nfree. A joint numerical evaluation project is being carried out by scientists\nfrom PMEL and NMC. Preliminary results indicate that the movement of ice in\nthe southern and central Bering Sea is predicted to within 15% when forecast\nwinds match the observed winds. Also, the forecast model was found useful at\nsix days, apparently because the ice is an integrator of atmospheric and\noceanic processes and because the spectral atmospheric model appears to\nperform well in winter at 60°N latitude.\nThe ice model does not contain enough physics to be applicable to the\nextreme northern Bering and Chukchi Seas, so that extension of the forecast\nmodel northward depends on tackling some difficult scientific problems. The\nprincipal missing physics is the effect of barotropic and baroclinic currents\nand the influence of islands and headlands on the drift of the ice.\nIce Edge Physical Oceanography\nCurrents on the central Bering Sea shelf between the 50-m and 100-m iso-\nbaths are weak and variable during the ice-free months. The resultant north-\nwestward flow has mean current speeds of less than 5 cm s-1, and frequent flow\nreversals occur. An intensive suite of current, temperature, and salinity\ndata was obtained in winter 1982-83 during MIZEX-West. These data show that\nover the February-April 1983 period, which coincided with greatest southward\nice extent, the otherwise sluggish flow was strongly augmented by a northwest-\nward baroclinic current that underlies the ice edge. Within this current the\nobserved mean speeds exceeded 10 cm S , and no reversals to eastward flow\nwere observed. The baroclinic current appeared to be' filamentous, having\nhigher speed cores separated by regions of lower speed. The current was about\n100 km wide and parallel to the ice edge.\nThe baroclinic ice edge current is due to the combined influence of\nlocalized ice melting along the ice edge and regional temperature and salinity\ndifferences between the Bering shelf water and the warmer, more saline water\nto the south. Its location appears to be related both to that of the ice edge\nand to local bathymetric features. Its associated ocean frontal structure\nmust interact strongly with the ice edge location both through advection by\nthe northwestward currents and through frontal heat transfer processes. The\nnorthwestward transport of water, considerably greater than during ice-free\nperiods, would be expected to affect regional biological processes as well.\nPredicting Currents in the Bering Strait\nBering Strait provides the only avenue of exchange between the Pacific\nand Arctic Oceans. This exchange is critical to the regional mass and heat\nbudgets, and thereby to the regional ice cover. The exchange also substan-\ntially influences the density structure of the Arctic Ocean and the input of\nnutrients to the Arctic Ocean. Finally, recent work suggests that the ice\ndrift itself is primarily determined by a balance between currents and winds.\nSuperimposed on the strong mean northward flow through the strait are\nlarge fluctuations at synoptic time scales, apparently forced meteorologi-\ncally. These fluctuations include reversal of the flow through the strait,\ndriving both water and ice southward into the Bering Sea.\n84","Two-thirds of the variance of the flow through the strait is predicted by\nthe local geostrophic wind. The physical basis for this high predictability\nis the convergence of the wind-driven flow occasioned by the various restric-\ntive passages and coastlines, first and foremost being Bering Strait itself.\nThis convergence sets up a barotropic pressure field in the ocean, which\nmodifies the flow. The observed currents, oceanic pressure gradients, and\ngeostrophic winds are all compatible with this simple conceptual model.\nTides in the Bering Sea\nRecent observations by PMEL and others of bottom pressure and currents on\nthe Northeastern Bering Sea Shelf have been analyzed for tides and tidal cur-\nrents to document the oceanographic conditions and calibrate numerical models\nfor the Navarin Basin, an economically important region west of St. Matthew\nIsland. The analysis showed that the diurnal tides dominate the outer shelf.\nThe diurnal amplitudes decrease exponentially inshore from the shelfbreak at a\nrate consistent with subinertial Sverdrup waves. The phase lags of the\ndiurnal tides vary little over the shelf. The semidiurnal amplitudes vary\nconsiderably. The semidiurnal phase lags are earliest at the shelfbreak and\nincrease toward the north and east. The semidiurnal tides on the outer shelf\nappear to be under the influence of an amphidromic system located off Cape\nNavarin.\nThe tides become progressively smaller and more semidiurnal toward Bering\nStrait. There are some seasonal variations in the observed tides with\nslightly large diurnal amplitudes on the outer shelf and smaller semidiurnal\namplitudes in the strait in late winter. A comparison with numerical models\nshows that the models reproduce the general features of the observed tides and\ntidal currents on the Northeastern Bering Sea Shelf.\nHAZARDOUS WINDS\nDuring February and March 1983, a study of mesoscale marine winds was\ncarried out over the coastal waters of the northwestern Gulf of Alaska. A\nclosed low-pressure region was centered over the south Alaska Peninsula, and\nits associated occluded front curved eastward, then southeastward from the\nPMEL\nnortheastern tip of Kodiak Island. Perhaps the most striking feature of the\nmesoscale pressure field is the perturbation pattern over Shelikof Strait.\nSurface pressures were as much as 0.5 mb higher on the west side of the strait\nthan on the east side. The undisturbed geostrophically balanced winds in the\nvicinity of the entrance to Shelikof Strait were about 8 m s-1 in strength\nwith a strong easterly component. This flow behavior maintained itself to\nabout a third of the way down the strait where it quickly backed to north-\neasterly, following the channel axis, and accelerated to 15 m s-1. Gap winds\npersisted through this part of the strait but decelerated as they approached\nthe southern terminus. At the exit the flow abruptly changed to a more geo-\nstrophically balanced wind field. Farther south, as the aircraft approached\nthe storm center, the winds became southerly and light.\nThe complicated wind regimes in straits, which develop in response to\ndifferent large-scale pressure fields, have also been theoretically investi-\ngated by scale analysis of the equations of motion. Adjustment of the mass\nand motion fields in straits that are 10's of kilometers wide, such as\n85","Shelikof Strait and the Strait of Juan de Fuca, is governed by four non-\ndimensional numbers: along- and cross-strait Rossby numbers, a drag co-\nefficient, and a stratification parameter that relates the internal Rossby\nradius of deformation to the width of the strait. The wind field will be in\napproximate geostrophic balance with an imposed cross-channel pressure\ngradient. An along-channel pressure gradient is primarily balanced by\nageostrophic acceleration of the wind field down the axis of the strait, the\ngap wind. Vertical motion and the accompanying horizontal divergence in the\nnear surface wind field can be large even for moderately stable stratifica-\ntion. As a consequence, there may be particularly abrupt transitions of the\nsurface wind field at the exits of straits, where there is a rapid change of\nthe scaling parameters to match coastal conditions.\nThe scale analysis also applies to open coasts; the Rossby radius of\ndeformation replaces the width of the strait as the offshore length scale.\nFor the mountainous coasts of Alaska, Canada, and Norway, a typical Rossby\nradius is about 80 km; within this distance an alongshore pressure gradient\nwill be principally balanced by the ageostrophic terms in the momentum equa-\ntion, and gap wind type accelerations should occur near shore. Since the\ncoastal Rossby radius is smaller than the grid size of present numerical\nweather prediction models, geostrophic adjustment is not correctly modeled for\nland-falling storms along mountainous coasts.\nHAZARDOUS WAVES\nThis project conducts research in ocean wave dynamics, especially coastal\nwave phenomena that create hazards to life and property. Previous research by\nPMEL led to the development of an improved algorithm for forecasting sea state\non the Columbia River Bar. Two extensions of this work were completed in the\nlast year. First, the algorithm was adapted to the entrance at Grays Harbor,\nWash. Second, both procedures were automated by designing and implementing an\ninteractive computer program incorporating the Bar forecast model in coopera-\ntion with the Northwest Ocean Service Center. As a consequence, the procedure\nis more systematic and consistent, and the preparation time for an operational\nforecast has been significantly reduced. The algorithm has provided a 25%\nimprovement in wave-forecasting accuracy.\nFurther analysis of the remote-sensing data acquired at the Columbia\nRiver entrance during previous experiments has shown several instances in\nwhich focusing of wave energy by wave-current refraction is important for wave\namplification and the existing (one-dimensional) forecast algorithm under-\npredicts wave height on the Bar. For a given wave period, the amount of\nrefraction depends primarily on details of the surface current distribution,\nsuch as the degree of lateral shear, and also on the incidence angle of waves\nrelative to the main current axis. The relative importance of these two\nfactors of the Columbia River is unknown, and a numerical study is planned to\nexplore the sensitivity of wave height amplification to each.\nFISHERIES-OCEANOGRAPHY RESEARCH\nFisheries-oceanography planning activities and program development con-\ntinued in anticipation of future initiative funding. A plan was developed for\nthe Fisheries Oceanography Experiment (FOX), a multidisciplinary study to be\n86","conducted in Shelikof Strait, Alaska, in winter-spring 1984-85. This investi-\ngation will improve understanding of environmental factors that influence\npollock behavior and abundance. Comprehensive sampling of the biota is\nplanned to be carried out from March to June 1985, and currents, water\nproperties, and winds will be measured before and during this phase.\nCooperative studies and planning workshops were coordinated with IRIS\n(International Research Investigations of the Subarctic), a regional council\nthat involves U.S. and Canadian fisheries researchers in the northeast\nPacific. Time series of oceanic observations (both physical and biological)\nare being documented for use by researchers.\nTo improve understanding of the large-scale circulation patterns in the\nFOX region, an analysis of current observations of 10 months duration at two\nsites in the Alaskan Stream off Kodiak Island was completed. This study\nrevealed that the flow in the Alaskan Stream is relatively steady in compari-\nson with other western boundary currents, the transfer of eddy momentum is\nquite small and is toward smaller scales, and a cross-shelf transfer of heat\nby eddy processes does occur. Sea level and other time series data have been\nused to describe the westward extension of the coastal Kenai Current. It\nretains its flow characteristics in these waters, and its subsequent transport\nthrough Unimak Pass also affects circulation and conditions in the shallow\neastern Bering Sea.\nTSUNAMIS\nThe U.S Office of Foreign Disaster Assistance of the Agency for Inter-\nnational Development has commissioned NOAA through PMEL to conduct a 3-year\nproject known as THRUST (Tsunami Hazard Reduction Using System Technology).\nThe goal of the project is to demonstrate that a satellite-based regional\nwarning system can be assembled and integrated into an established disaster\nwarning and relief network of a developing nation.\nIn June of 1983 the contract was awarded. The project began in September\n1983 when the project team conducted a site visit to Chile. After the THRUST\nconcept was discussed with the Chilean Navy Hydrographic Institute, the final\nresearch and demonstration plan was established. Since that time, the know-\nledge and skills of three NOAA components, two subcontractors, an AID advisor,\nPMEL\na program director, and a project coordinator have been used to complete the\nfirst year's work.\nThe system being developed uses existing seismic instrumentation\nconnected to satellite communication to establish a warning system. This\nsystem will enable Chile to obtain rapid data acquisition and analysis, and\nquick information dissemination.\nIn addition, bottom pressure recorders have been deployed in the equato-\nrial Pacific to record the characteristics of passing tsunamis in the open\nocean. These deployments are for 6-month intervals. Several small tsunamis\nhave been recorded, as well as signals from distant storm events.\n87","Plans FY 1985\nSEAICE RESEARCH\nConduct APEX (Arctic Polynya Experiment). This experiment in the\nnorthern Bering Sea will study regional currents and sea ice drift to\nprovide the scientific basis for extending the sea ice forecasting model\nto the northern Bering and Chukchi Seas.\nHAZARDOUS WINDS\nPlans will be developed for major west coast experiment \"Ocean Storms\",\nto occur in fall 1986.\nHAZARDOUS WAVES\nThe Columbia River Bar algorithm will be updated, and an improved\nsuperstructure icing algorithm will be developed.\nFISHERIES-OCEANOGRAPHY RESEARCH\nConduct FOX (Fisheries Oceanography Experiment). This experiment will\nmeasure seasonal and storm-driven currents near the southern end of\nShelikof Strait, Alaska, a rich pollock spawning ground. An intensive\nstudy period in March 1985 with the NOAA ship Discoverer and a NOAA P-3\nresearch aircraft will concentrate on ocean divergence and advection\ncaused by local wind effects. FOX will also support improved\nmeteorological forecasting for southern Alaska.\nTSUNAMIS\nAn expanded tsunami effort will combine modeling activity with the\ncontinuation of THRUST.\nMARINE RESOURCES\nHydrothermal venting, which occurs along sea floor spreading centers,\nrepresents a basic input of heat and materials into the oceans. The effect of\nhydrothermal venting on the marine environment is the focus of PMEL's marine\nresources program, \"VENTS\". Research efforts have been specifically designed\nto define and quantify the chemical, geological, and physical oceanographic\nprocesses evolving from the venting of hydrothermal fluids. Current studies\nof hydrothermal venting have focused on the Gorda and Juan de Fuca ridges.\nAccomplishments FY 1984\nThe Marine Resources Research Division at PMEL was created in January\n1984 to conduct research into seafloor spreading processes such as the venting\n88","of high temperature fluids from geologically active areas of mid-ocean ridges.\nThe principal activities of this new division were establishment of the VENTS\nprogram, reprogramming of the efforts of the former Marine Geology and Geo-\nphysics Group of the National Ocean Service, and relocation of activities from\nRockville and Seattle to the Mark 0. Hatfield Marine Science Center in Newport,\nOregon. The VENTS program is designed to assess the consequences of high-\ntemperature hydrothermal venting. From a geochemical perspective, these hydro-\nthermal venting systems have significant impact (at least on local to regional\nscales) on the oceanic thermal and mass budgets. The venting systems are a\nmajor source for mineralization of sea floor sediments and a primary source\nfor the formation of a variety of metallic sulfides. Further, the close assoc-\niation between active venting and characteristic vent-communities provides an\nimportant element in NOAA's ongoing research in marine living resources. In\nFY 1984 one objective was to define research that will provide a more integra-\nted examination of the overall importance of the venting systems.\nFour separate VENTS experiments were conducted during FY 1984, which were\npartially a legacy from the several pre-VENTS research efforts. In March and\nApril, the NOAA ship Surveyor conducted seafloor investigations, including\ncollection of bathymetry from the Hec, Heckle, and Vance Seamount Chains.\nContouring at 10-m intervals was completed aboard the ship during the cruise.\nMeasurements were taken to fill gaps in data from the Gorda Ridge between the\nBlanco Fracture Zone and the Escanaba Trough, to compare and contrast the\ntectonics of the Gorda and the Explorer Ridges (two ridges close to the\ncontinent), and to examine the effects of the nearby continent on ridge\nstructure.\nIn May and June, the Discoverer was utilized for the \"PENTAFLUX\"\nexperiment on the southern Juan de Fuca Ridge, which focused on geochemical\nsampling and characterizing of vent-associated plumes and nearby sediments.\nSediments on the Juan de Fuca Ridge and along its flanks to distances in\nexcess of 100 km normal to the ridge axis displayed a pronounced hydrothermal\nsignature. Elevated abundances of iron and manganese in the sediments and\nmethane and suspended particulate matter in the water column proved to be\nexcellent indicators of hydrothermal activity. Shipboard techniques have been\ndeveloped for pseudo-real-time detection of these parameters, resulting in the\nability to define the intensity and distribution of the hydrothermal plume.\nSLEUTH (System for Locating Eruptive Underwater Turbidity and Hydro-\nPMEL\ngraphy), which was designed and deployed by PMEL during FY 1984, has proved to\nbe a unique continuous sensor for the detection of hydrothermal plumes.\nUltra-sensitive and precise detectors for light scattering, temperature, and\nconductivity on the SLEUTH mainframe were towed through the lower several\nhundred meters of the water column to define the plume distribution over the\nridgecrest. SLEUTH-detected regions of enhanced hydrothermal activity were\nthen surveyed with discrete sampling devices to provide a more complete geo-\nchemical description of the hydrothermal plume at its origin. Some of the\nmost hydrothermally enriched samples yet collected from a surface vessel\nresulted from these operations.\nHydrothermal fluids and particulates were also collected from several\nregions of the Juan de Fuca Ridge using the research submersible Alvin. These\nsamples were several hundred thousand times more enriched than those obtained\nfrom surface, ship-based operations. Specially designed titanium samplers\ncapable of withstanding temperature and pressure differentials of 380°C and\n89","600 atmospheres were deployed directly within hydrothermal vent orifices less\nthan 10 cm in diameter, through which hot gas and metal-charged fluids were\nrapidly discharged. Concentrations of the various hydrothermal fluid\ncomponents will be estimated from the these samples and employed for modeling\nof plume processes. Some exploratory water samples were taken at Blanco\nTrough, the Surveyor and Cascadia Depressions, and over a topographic high\nalong Rift B on the southern Juan de Fuca Ridge. Box cores were collected at\nall but the last site.\nA mooring with sediment traps and current meters was also deployed, to be\nrecovered by the USGS Alvin in October 1984 during a USGS cruise. This will\nextend observations obtained during PENTAFLUX.\nOperational dives by Alvin for VENTS were conducted during July and\nAugust. The July dives were an investigation of proposed active venting sites\nin the Escanaba Trough, on the Gorda Ridge, in the \"pull-apart\" basins of the\nBlanco Fracture Zone, at the southern Juan de Fuca Ridge (where the PENTAFLUX\nwork had been done earlier), along the axial portion of the central and\nnorthern Juan de Fuca Ridge, and on the Endeavor Ridge sector. This was the\nfirst series of Alvin dives along the Northeastern Pacific Ridge System and\nwas considered to be exploratory. Dives were located along the whole ridge\nsystem at sites that prior information indicated had the highest probability\nof active hydrothermal venting for representative sectors of the ridge crest.\nThe data collected support the general model that indicates lack of active\nhydrothermal venting along the southern Gorda Ridge, and progressively increas-\ning activity northward along the Juan de Fuca Ridge. Relatively important\nevidence of venting (smokers and living vent communities) was found at the\nAxial Seamount and on Endeavor Ridge. Successful attempts were made to sample\nmineralized sediment, vent organisms, or other deposits associated with the\nactive vents. Water samples were collected at the venting sites for chemical\nanalyses of both the water and the suspended particulates.\nThe August series of Alvin dives was along the convergent plate boundary\nat the subduction zone along the base of the 0regon-Washington continental\nslope. VENTS-supported investigation of interstitial and extruded water\nsamples provided insight into an unexpectedly abundant benthic community that\nwas discovered during the dive series. The community bears strong initial\nsimilarities to the hydrothermal vent communities (tube worms and large clams)\nfound along the spreading centers, although high-temperature water is not\npresent. On the basis of shipboard examination, methane was identified as a\npossible basic component of a localized chemosynthetic primary production.\nA 1-day workshop on \"Long Range Research Objectives at the Gorda and Juan\nde\nFuca Ridge Environments\" was held at the Hatfield Marine Science Center in\nJune. This was jointly sponsored by the VENTS Program and Oregon State\nUniversity marine biologists.\nA major requirement for the activity planned at Newport is the\nacquisition of VAX-based data processing capability to be used to process and\nanalyze \"SEABEAM\" and similar data for research use. The administrative\nrequirements and the necessary clearances and approvals went relatively\nquickly, and delivery of initial hardware was made in late August.\n90","Plans FY 1985\nContinue to develop ADP processing system for SEABEAM data. First\nprototype research charts are planned for completion by March 1985.\nConduct research cruise to Gorda Ridge to search for active, high-\ntemperature hydrothermal venting systems.\nConduct research cruise to Axial Seamount, Endeavor Ridge, and southern\nJuan de Fuca Ridge to sample and characterize vent fluids and near-field\ngeochemical processes at known active vent sites.\nConduct a workshop to report on the status of recent VENTS research to be\nheld at Newport in March 1985.\nPMEL\n91","","GREATLAKES ENVIRONMENTAL\nEugene J. Aubert\nRESEARCHLABORATORY\nDirector\nArbor, Michigan\nDirector\nO/P\nDep. Director\nESG\nCooperative\nCRP WRP PROFS WMP\nInstitutes\nAOML\nPMEL\nGLERL\nGFDL\nNSSL\nWPL\nARL\nAL\nSEL\nThe Great Lakes Environmental Research Laboratory (GLERL) conducts\nintegrated, interdisciplinary environmental research in support of resource\nmanagement and environmental services in coastal and estuarine waters, with\nspecial emphasis on the Great Lakes. It performs field, analytical, and\nlaboratory investigations to improve understanding and prediction of coastal\nand estuarine processes and interdependencies with the atmosphere, land, and\nsediments; places special emphasis on a systems approach in problem-oriented\nresearch to develop environmental service tools; and provides assistance to\nresource managers and others in obtaining and applying the information and\nservices developed. The environmental information is provided to government\nand private organizations to facilitate planning and decision making in water\nresource management. The GLERL program includes both basic and applied stud-\nies and combines experimental, theoretical, and empirical approaches.\nResearch is carried out through five groups: Synthetic Organics and\nGLERL\nParticle Dynamics, Ecosystem and Nutrient Dynamics, Lake Hydrology, Physical\nLimnology and Meteorology, and Environmental Systems Studies. Disciplines and\nactivities include aquatic chemistry and biology, applied mathematics,\nmeteorology, geology, hydrology, physical oceanography, ecology, computer\nsystems applications, instrument design and development, and experimental\ndesign and analysis.\nGLERL's multidisciplinary program reflects needs for improved under-\nstanding, prediction, and specific information about the Great Lakes.\nBiogeochemical studies of the cycling and dynamics of nutrients and toxic\ncontaminants are needed to improve understanding and prediction of processes\noccurring in the Great Lakes ecosystem and to provide more precise scientific\ninformation relevant to the management of wastes, water supplies, and\nfisheries. Models to simulate and predict the transport and fate of con-\ntaminants as a function of human input to the lakes are needed to support\nmanagement decisions on wastewater and regulation policies. More precise\n93","scientific information on lake water levels, connecting channel flows, and ice\ndistribution is useful to those concerned with erosion control, transpor-\ntation, recreation, and power generation. Studies of the lakes' physics\nimprove understanding and prediction of the circulation, the thermal struc-\nture, and the transport and dispersion of chemical and biological variables in\nthe ecosystem; numerical forecast tools result in products applicable to\npollution transport and dispersion. Research on physical phenomena like sur-\nface waves, seiches, and surges provides improved understanding and numerical\nprediction methods that are applicable to shipping activities, recreation,\nshoreline flooding, and erosion.\nOCEAN AND GREAT LAKES RESEARCH AND ASSESSMENT\nOcean and Great Lakes Research and Assessment activities at GLERL are\ndirected toward (1) improving understanding and prediction of natural marine\necosystems, physical phenomena, and the impact of human-induced stresses on\nthe ecosystem, and (2) developing a sound scientific basis for management\ndecisions pertinent to marine resources, marine pollution, and environmentally\nsensitive marine activities. Activities in support of this program include\ninvestigation of the short- and long-term effects of human, agricultural, and\nindustrial wastes on aquatic life and water quality, particularly in the\nnearshore zone (the area of maximum use and conflict) measurement, analysis,\nand prediction of physical phenomena such as currents, lake levels, river\nflows, and sea-air-sediment interactions; and participation as representatives\nof NOAA and the Department of Commerce in regional, national, and inter-\nnational organizations addressing problems of the Great Lakes.\nAccomplishments FY 1984\nSeasonal composition and abundances of epibenthos were examined to deter-\nmine how much microcrustacean biomass occurs in the sediments relative to\noverlying waters in nearshore Lake Michigan. These forms peaked at different\ntimes in the sediments (spring and early summer) than in pelagic waters (late\nsummer or not at all).\nThe survival and viability of the meroplanktonic diatom Melosira\ngranulata is being investigated in cooperation with University of Michigan\nscientists. This diatom remains viable for periods of at least 100 years\nwhile buried in the sediments and is capable of photosynthesis immediately\nupon exposure to light.\nThe effects of nutrient patchiness on the composition of natural\nassemblages of algae were examined in laboratory experiments. Patchy supply\nresulted in dominance of a single blue-green algal species, whereas homo-\ngeneous supply resulted in co-dominance among the blue-greens, flagellated\ngreens, and a diatom. These results demonstrate that the mechanism of\nnutrient supply can affect algal composition in the Great Lakes.\nCorrelation of benthic invertebrate abundance with measurements of\nnutrient release from intact sediment cores indicated that Pontoporeia hoyi\nmay suppress silica release from sediments by burying the silica-rich sur-\n94","ficial floc layer. This information is needed to understand and model the\ndynamics of nutrient release from Great Lakes sediments.\nAmmonium excretion rates by several life stages (nauplii to adult) of the\nmarine copepod Eucalanus pileatus were measured in two controlled food\nenvironments to assess the importance of life stage and food abundance on\nnutrient regeneration by zooplankton. When food was abundant, animals of all\nstages released ammonium at similar rates per unit ash-free dry weight, but at\nlow food levels, late-stage juveniles and adult females released ammonium\nsignificantly more slowly than did the nauplii or early stage juveniles.\nA temperature-diffusion model was calibrated for a 20-year data set from\nLake Washington, and estimates of vertical turbulent diffusion coefficients\nwere completed. These diffusivities were used to model a nearly conservative\nsubstance--total alkalinity.\nDocumentation of the results of the major (e.g., current meter moorings)\nyear-long (1979-80) Lake Erie experiment was completed. Analyses of\nthermistor chain profile data define the seasonal development and decay of\nstratification in the central basin and its response to storm wind events.\nCurrents measured in the lower half of the central basin water column were\nmostly return flows (beneath the surface wind drift) driven by the surface\npressure gradient. A complex system of Lake Erie circulation gyres was often\nobserved; it was close to that predicted by models, although there was a ten-\ndency for one of the central basin gyres to become dominant and envelop the\nwhole basin in either uniform clockwise or uniform counterclockwise flow.\nThe\ncurrents were somewhat more barotropic than predicted by full Ekman layer\ncurrent models. Tide-like currents, driven by the longitudinal seiches of\nLake Erie, occur in the island passages between the western and central Lake\nErie basins.\nGLERL and the Canada National Water Research Institute are working\ntogether to synthesize knowledge and recent Lake Erie research accomplishments\nin a series of articles. A key topic is a synopsis of the Lake Erie current\nmeter studies described above. Analyses of the current meter measurements\ndone with a new objective analysis method are also discussed and compared with\nthe results of a time-dependent numerical circulation model. The objective\nanalysis method uses the observed currents as constraints on an energy and\nvorticity minimization scheme and low-pass filtered current meter data to\nGLERL\narrive at a two-dimensional stream function field. The numerical model uses\nthe rigid lid approximation and demonstrates the sensitivity of the\ncirculation pattern in the flat central basin of Lake Erie to the curl of the\nimposed wind stress (e.g., a difference of 3 m S s-1 in the eastward component\nof the wind speed over a north-south distance of 100 km is sufficient to\ngenerate a one-gyre circulation pattern in the central basin).\nA study recently completed describes currents and water temperatures\nmeasured in the four main passages between Green Bay and Lake Michigan and at\nseveral sites within the bay during summer and fall 1977. Monthly resultant\ncurrents indicate counterclockwise circulation in the bay during dominant\nsouthwesterly wind, while there is a rapid reversal of this pattern during\nepisodes of northeasterly wind. Oppositely directed two-layer flow through\nthe mouth is a common feature during the stratified season. Cold hypolimetic\nlake water entering through the mouth and extending far into the bay remains\nstratified and promotes flushing.\n95","A two-dimensional, vertically integrated circulation model has been used\nto study the importance of Ekman layer physics to the sedimentation patterns\nof southern Lake Michigan. One experiment used a circularly symmetric\nidealization of Lake Michigan's southern basin, a \"typical\" Great Lakes storm\nsystem (represented by one day with strong west wind and four days with no\nwind), and a sediment source assumed uniform over the surface of the idealized\nlake. The results of a comparison of sediment deposition and erosion for\nmodels with and without Ekman physics confirm the theory that deposition tends\nto occur preferentially in cyclonic gyres. The next step will involve a\n6-month simulation using real Lake Michigan bathymetry and wind forcing and a\ncomparison of results with observed sediment patterns.\nStudies have been conducted with current drifters in Lake Michigan to\ndetermine whether they can be used confidently as indicators of particle tra-\njectories. A cluster of three drifters was deployed in a patch of rhodamine B\ndye. Dye concentration was determined by fluorometry and the center of mass\ncalculated from continuous sampling profiles. Separation of the centroid of\nthe drifters and the dye center of mass was compared with wind data and used\nto calculate the slippage velocity.\nRecent work in synthetic organics and particle dynamics has concentrated\non making laboratory measurements of Kp (the equilibrium partition\ncoefficient) for a series of radiolabeled organic compounds ranging over four\norders of magnitude in solubility onto the settling particulate matter\ncollected monthly in offshore Lake Michigan sediment traps. Initial results\nindicate there is less than an order-of-magnitude change in Kp on the settling\nmaterial over a single season.\nIn addition, a substantial fraction of the operationally defined\n\"dissolved\" contaminant was found to be weakly bound to natural dissolved\norganic matter by extensive laboratory work on the three-phase system\n(particulate-bound-dissolved) Bioavailability of organic xenobiotics from\nwater is reduced when dissolved organic carbon (DOC) is present; DOC can be\nmeasured by short-term static uptake experiments.\nApproximately 100 sediment traps were deployed and retrieved throughout\nLake Michigan over the past year. From these measurements, the rates of\nsettling of particulate matter and, after chemical analysis, the fluxes of\nvarious contaminants can be estimated. Sample analysis for several con-\ntaminants is currently under way. Initial analyses of the data have two major\nresults: First, it appears that traps deployed offshore above or immediately\nbelow the thermocline during stratification are useful in estimating the new\nload (predominantly atmospheric) of material entering the lakes, and second,\nresuspension during the unstratified period (November-June) is very great and\nprovides a mechanism for intimate coupling between the water column and recent\nsediments.\nThe regional radionuclide source function has been put together and\nentered on the VAX 11/780 computer system for use in calibrating long-term\ncontaminant response models. In addition, the contaminant model for Lake\nMichigan was developed into a coupled lakes model for the Great Lakes system.\nIn another effort, residence times for DDT, PCB, and the polycyclic aro-\nmatic hydrocarbon (PAH) anthracene were estimated for the surface microlayer.\n96","The analyses focused on estimating the response times of the surface micro-\nlayer to departures from equilibrium conditions. Equilibrium conditions were\ndetermined from literature-based values of model parameters, which included\nsettling, photolysis, eddy transport, partitioning, and volatilization.\nResults indicated that little additional effort is needed on microlayer\nresearch.\nWork on thermal forecasting models is also progressing. To date, three\ndifferent types of one-dimensional thermal forecasting models have been\nprogrammed and soon will be tested against data from Lakes Erie and Michigan.\nThe three types used are (1) inertial deepening, (2) turbulent erosion, and\n(3) eddy diffusion. Each model is unique and has attractive features, but\nsuffers from one or more limitations adjustable coefficients). The\nmost accurate model will be selected by rigorously comparing model simulations\nwith observations.\nMost contaminants of concern adhere to particles and rapidly settle out\ninto the sediments. An important process for remobilizing contaminants from\nsediments involves direct uptake by benthic invertebrates and transfer up the\nfood web to higher trophic levels. Studies focus on measuring the uptake of\ncontaminants by benthos and developing models of this process and the trophic\ntransfer process. Our field results indicate that the common benthic amphi-\npod P. hoyi and oligochaete worms have significantly higher concentrations of\nPAH than do the surrounding sediments. Two models have been developed. The\nfirst is a nonsteady-state model for the time-dependent uptake, depuration,\nand metabolic decomposition of PAH by P. hoyi. The necessary temperature-\ndependent coefficients are being refined by laboratory studies. A second\nmodel, being developed under contract, uses the concept of bioenergetics to\npropagate caloric energy (and contaminants) up the food web. Results from\nmodel calibration runs for alewife, a mid-trophic-level planktivore, indicate\nthat a substantial fraction of the fish's PCB body burden is derived from\nfeeding on benthos.\nWork currently being pursued will determine the relative bioavailability\nof material attached to the sorbed phase and the dissociation of sorbed xeno-\nbiotics. The seasonal toxicokinetics of PAH to P. hoyi are currently being\nrepeated with measurements of sorption to DOC, lipid content of the animals,\nand organism size to attempt to define some of the variables that appear to\ncause the apparent seasonal variation in the toxicokinetics. In addition to\nthese studies, there are under contract two projects on the development of\nGLERL\ntechniques to measure chronic effects of PCB's and PAH on benthic inver-\ntebrates. The first of these involves the analysis of the distribution of\nfree amino acids in the organism and changes when the organisms are exposed to\nchemical stresses. The second procedure is designed to measure changes in the\nrate of activity (sediment mixing for the oligochaetes being tested) when the\norganisms are exposed to chemical stress.\nThe field portion of our Hi-Sed program has been completed with the\ncollection of cores from the regions of high, recent, sediment accumulation in\nLake Superior. We now have carefully collected sets of cores from all five\nGreat Lakes. Results have supported previous reports of a near-surface layer\nof mixed sediments. A major advance is the development of a nonsteady-state\nmodel and an associated computer program to simulate the effects of zoobenthos\nfeeding and mixing on sediment tracer and contaminant profiles.\n97","A qualitative study of the temporal impacts of St. Clair River dredging\non the flows in the St. Clair, Detroit, and Niagara Rivers and on the levels\nof Lakes Michigan-Huron, St. Clair, and Erie has been completed. Maximum\nimpacts occurred near the end of the dredging project for the St. Clair and\nDetroit Rivers and Lake St. Clair and lag by about a year impacts on Lake Erie\nand the Niagara River.\nA series of software packages, from data acquisition through model appli-\ncation, has been developed for ultimate use in generating deterministic runoff\noutlooks in near-real time. Development of the near-real-time data acquisi-\ntion system is continuing. Procedures have been initiated for including\nsubstantial amounts of Canadian meteorological data on the National Weather\nService (NWS) weather wire and for the rapid receipt of data from second-order\nstations.\nEquivalent channel sections based on measured hydrography have been used\nto revise the upper Detroit River unsteady flow model. The model is currently\nbeing modified to include the various islands and channels. A new dynamic\ncalibration procedure has been developed; it will significantly improve the\nmodel results over those obtained from the static calibration procedure that\nhas been used by all agencies in the past.\nThe Great Lakes hydrologic data base recently published provides Great\nLakes researchers and managers with a readily available comprehensive source\nof data.\nThe Large Basin Runoff Model, data reduction packages, and several large\ndata bases were transferred to the U.S. Army Corps of Engineers; a corps\nemployee was trained in use of the model.\nA recently developed automated computer forecast package for Lake\nSuperior uses near-real-time meteorological data to produce operational out-\nlooks of basin runoff for improving lake level regulation. The package is\ncomposed of (1) data acquisition and reduction by a computer system that moni-\ntors interagency data links and updates provisional meteorological station\nnetworks, (2) the automatic computation of weighted subbasin meteorological\ndata files from the provisional station data, and (3) the semiautomatic\ndistributed-parameter application of GLERL's Large Basin Runoff Model with\nsuitable graphical interpretations.\nThe study of the St. Clair and Detroit Rivers winter flow regimes con-\ntinued with successful completion of the field season for continuous current\nmeasurements in the St. Clair River at Port Huron. The season was marked by\nsevere cold spells during December and January, causing frazil ice and a\nrecord ice jam in April.\nData analysis and evaluation from the 1983 Lake Michigan Ecosystem\nExperiment was completed for water column nutrients, sediment trap chemistry,\ncommunity level phytoplankton growth, and zooplankton grazing. This data set\nis unique because all the processes known to contribute to growth and loss of\nphytoplankton were measured simultaneously from the same water mass.\nData from the Lake Michigan Ecosystem Experiment suggest that the quality\nof water in the lake has improved a great deal over the last year.\nTransparency of the water column has increased dramatically. The hypothesized\n98","reason for this change is an increase in large cladocerans and a reduction in\nalgae due to increased predation on, and rapid decline of, the alewife popula-\ntion. The decrease in the alewife population was caused by stocking of salmo-\nnids and other game fish in Lake Michigan.\nThe abundance and importance of small (<1 um diameter) cyanobacteria in\nLake Superior were demonstrated. Bacteria-sized phytoplankton accounted for\nabout one-half of the total primary production and exhibited growth rates of\ntwo to four divisions per day. Microzooplankton, such as protozoa, appear to\nbe consuming this production, These very small organisms constitute an impor-\ntant, but previously unrecognized, part of the Lake Superior food chain.\nExperimental data on the relative importance of phosphate and silicate\nlimitation reveal that diatoms outcompete blue-green and green algae because\nthey have transport constants for phosphate uptake that operate more effec-\ntively on low substrate concentrations. This could account for diatom suprem-\nacy during all periods except when silica limits diatom growth.\nPhosphate uptake kinetics and computer simulations suggest that mixed\nmicrobial assemblages have half-saturation constants from one-half to\none-third lower than those shown previously in laboratory cultures.\nPhosphorus stress apparently induces microorganisms to produce high-affinity\nuptake systems, thus allowing relatively rapid growth rates at low ambient\nphosphate concentrations This helps explain the controversial paradox of\nhigh phytoplankton growth rates when phosphate concentrations are very low in\nlake and ocean waters.\nThe relation between zooplankton feeding rate and food concentration for\nlaboratory cultures of algae and for lake seston was determined in order to\ntest an effective food concentration model. Results concurred with the model\nand demonstrated that feeding rates determined with algal cultures cannot be\napplied directly to lake seston.\nFrame-by-frame analysis of 140 films of copepod feeding showed that the\ncopepod Diaptomus sicilis is not an optimal forager (i.e. does not\nnecessarily select the most abundant available food), and supported the\naccuracy of the effective food concentration model. This information is\nneeded for an understanding of how zooplankton obtain food and affect the com-\nposition of phytoplankton seston in the Great Lakes.\nGLERL\nFilm analysis also showed that both the current-field produced and the\nfeeding behavior of D. sicilis differ from those of marine copepods. These\nresults explain why D. sicilis can specialize on small particles for food and\nalso why, for it, there is an invariant relation between particle selection\nand particle size. Based in part on these results, a model is being developed\nto describe the feeding rate of this copepod in mixtures of different par-\nticles such as those found in lake water.\nCalcite particles at the same concentration and size found during calcite\nwhiting in Lake Michigan were found to depress zooplankton grazing\nsignificantly. This depression was greater than that observed for clay\nparticles of the same concentration. Whitings in fecal pellets accelerate the\ndownward flux of the pellets up to tenfold.\n99","Nutrient transformation studies on silty Lake Michigan sediments indicate\nthat nitrogen released by macroinvertebrates as ammonium is rapidly converted\nto nitrate (nitrification) and then converted to nitrogen gas (denitrifica-\ntion) by microbes. These processes must be quantified to determine the impor-\ntance of sediment mineralization as a nutrient supply mechanism in the Great\nLakes.\nMicrocosm experiments indicate that invertebrate-mixing activities\nenhance phosphorus release from sediments, but that mixing beyond a threshold\nlevel has no effect on the rate of phosphorus release, (i.e., phosphorus\nrelease is not related to animal density). These studies are part of an\neffort to quantify the importance of aerobic sediments as a source of\nphosphorus in Lake Michigan.\nMicrocosm experiments demonstrated that invertebrates can enhance release\nof phosphorus from intact sediment cores. This source of phosphorus may\nexplain why disproportionately high levels of primary production have been\nobserved for nearshore regions.\nA new study was initiated to examine the role of P. hoyi in sediment\npelletization in Lake Michigan. This phenomenon may affect nutrient and con-\ntaminant cycling in lake sediments.\nUnder a grant, phosphorus regeneration rates of the predatory copepod\nCyclops bicuspidatus thomasi were examined as functions of temperature and\nprey. Temperature, prey density, and hunger level significantly and predict-\nably altered phosphorus release rates.\nMicrobial transformation rates of labile organic materials dissolved in\nlake waters were examined by measuring concentration decreases of low levels\nof amino acids added to Lake Michigan water. Amino acid turnover was slow\n(<1 nmole L - 1 during summer in offshore Lake Michigan.\nFirst-order estimates of bacterial growth in the Lake Michigan Ecosystem\nExperiment also indicate that turnover of organic carbon by bacteria is slower\nthan previously expected. These results indicate that bacteria may play a\nless important role in nutrient and energy cycling in the nutrient-poor lakes\nthan in nutrient-rich systems.\nPlans FY 1985\nSediment trap samples from Lakes Michigan, Superior, and Huron will be\nanalyzed for mass, contaminant organic, and nutrient concentrations. Fluxes\nwill be calculated.\nConcentrations of PAH will be measured seasonally in the major Lake\nMichigan benthic organism P. hoyi and compared with model predictions based on\nmeasured uptake and depuration rates.\nEquilibrium partition coefficients (concentration in solid phase/concen-\ntration in dissolved phase) will be measured for a wide range of organics on\nparticles collected in sediment traps. This will permit estimation of the\n100","impact of seasonal changes in particle composition on the phase distribution\nof contaminant organics.\nUptake from sediments and water depuration rates of contaminant organics\nby three major Great Lakes invertebrates will be measured using radiolabeled\ncompounds.\nA nonsteady-state sediment mixing model will be tested and calibrated\nwith sediment radionuclide data. The model simulates the effect of biotur-\nbation and resuspension on sediment cores over time.\nRadionuclide, contaminant organic, and trace metal analyses of cores from\nthe regions of highest sediment accumulation in each of the five Great Lakes\nwill be completed. The nonsteady-state sediment mixing model will be used\nto\ninterpret the profiles and the historical response of the lakes to contaminant\nloads.\nThe Lake Washington ecosystem model will be expanded to include total\nphosphorus and oxygen budgets. Analysis of long-term nutrient trends will\nalso begin. Model outputs will then be compared with field data to test the\nmodels.\nThe dynamics and importance of subsurface phytoplankton populations in\nLake Michigan will be determined. These populations are the dominant primary\nproducers during summer stratification.\nLake Superior will be studied to detect microbial food webs, as well as\nto determine the importance of picoplankton. These small organisms appear to\naccount for about one-half of the primary production in the lake.\nData collected from the 1983 and 1984 field phases of the Lake Michigan\nEcosystem Experiment will be analyzed and summarized. A single field\nexperiment will be carried out in 1985.\nMeasurements of bacterial growth rates and phytoplankton organic excre-\ntion rates in Lake Michigan during the 1984 field season will be analyzed and\nprepared for publication. In 1985 these measurements will be repeated with\nspecial emphasis on specific organic compounds excreted by phytoplankton and\nused by bacteria.\nGLERL\nExperimental data on the kinetics of phosphate and silicon uptake by\nphytoplankton will be evaluated to determine how silicon limitation affects\nphosphate uptake by diatoms and how diatoms and blue-green algae compete for\nphosphate in Lake Michigan.\nExperimental data on species-specific growth rates, phytoplankton\nstanding crops, and the kinetics of inorganic and organic phosphate will be\nanalyzed to test the hypothesis that microscale nutrient plumes from zoo-\nplankton provide a quantitatively significant phosphate source for algae.\nExperimental data on the kinetics of phosphate uptake by microorganisms\nwill be assessed to determine what primary forms of dissolved phosphorus are\npreferred by phytoplankton and bacteria and how these two types of organisms\ncompete and coexist in planktonic environments.\n101","A laboratory will be built for making high-speed motion pictures of\nzooplankton feeding and other interactions between zooplankton and phyto-\nplankton. This laboratory will allow us to continue the observations of\nzooplankton-phytoplankton interactions that we started on the high-speed\nmicrocinematography equipment at the Skidaway Institute of Oceanography.\nThe feeding response of zooplankton in mixtures of different species of\nalgae will be determined SO that a general model can be developed.\nThe significance of feeding history in relation to the feeding of\nzooplankton when they encounter new mixtures of algae (for example, during\nvertical migration into a new patch of algae) will be explored.\nA seasonal study on the amounts of lipids in various species of Lake\nMichigan macroinvertebrates will be completed. The results will yield sea-\nsonal caloric information on these organisms and provide insight relevant to\nthe biotic cycling of toxic organic compounds.\nThe caloric content of benthic macroinvertebrates in southern Lake\nMichigan will be estimated from ash-free dry-weight, lipid, and benthic\nabundance data. These data will be combined with reported turnover time\ndata for P. hoyi to estimate the energy flow through this dominant macro-\ninvertebrate in the lake.\nParticle-size selection and gut throughput rates of P. hoyi will be\nexamined to define the role of this amphipod in particle dynamics and pollu-\ntant transfer.\nThe distribution and feeding behavior of P. hoyi will be examined in\ndepositional areas of Lake Superior. This organism is a major source of food\nfor fish in the upper lakes.\nMicrocosm studies to quantify phosphorus release from Lake Michigan sedi-\nments will be conducted.\nAnalysis of invertebrate distributions will be completed to assess long-\nterm trends in Lake Michigan benthic fauna.\nA time-dependent solution (as opposed to a steady-state solution)\nalgorithm for predicting Great Lakes phosphorus dynamics will be coupled with\nan optimization algorithm for the purpose of identifying, on a yearly basis,\nleast-cost phosphorus management strategies that will produce desired\nphosphorus concentrations. Recommendations may change annually because of\nchanging costs of treatments and the natural variability associated with\nannual phosphorus inputs, ice cover days, and lake hydrodynamics.\nCurrent velocities in the benthic boundary layer of Lake Michigan will be\nmeasured to determine the climatology of high-current-speed events causing\nbottom sediment resuspension.\nThe GLERL Great Lakes Basin Supply Forecast package and near-real-time\nhydrometeorological data acquisition and reduction system will be finalized\nfor Lake Superior and further developed for Lakes Erie and Champlain.\n102","The experimental study of the St. Clair and Detroit Rivers winter flow\nregimes will be expanded. Remotely monitored electromagnetic current meters\nwill be used to make simultaneous point-flow measurements in both rivers.\nThese point measurements in the St. Clair River will be supplemented with con-\ntinuous vertical profile current measurements taken with an acoustical Doppler\ncurrent profiler.\nThe slippage between satellite-tracked drifter buoys and dye patches will\nbe observed during varying wind conditions to develop correction factors for\ncomparing drifter tracks with the results of spill model predictions.\nSatellite-tracked drifters will be used in a study of the Niagara River\nplume.\nModels of rotational wave motions in Lake Michigan will be compared with\nwave properties measured with current meters. Steady, seasonally varying\ncurrents observed in the lake will be used to describe prevailing lake-scale\ncirculations.\nData on the distribution of sediment in the southern basin of Lake\nMichigan will be used to test a numerical model of sediment transport,\nresuspension, and deposition. Early results of this study show that the\neffect of the Ekman boundary layer transport of sediment is important. When\nthis effect is included and when realistic wind patterns are used, the model\ncan reproduce the observed sediment patterns.\nThe Upper Great Lakes Connecting Channels Study is a new program (see the\nInternational and Interagency Activities section of this report) that will\naddress problems of synthetic organic pollutants and nutrient overenrichment.\nCurrent plans for GLERL activities involve the following:\nCalibrating models of conservative contaminant behavior from existing\ndata.\nExamining nutrient regeneration from sediments.\nField and laboratory studies to assess the status of contaminant problems\nin Lake St. Clair.\nDevelopment of a hierarchy of models for determining the fate, transport,\nand effects of selected nutrients.\nGLERL\nDevelopment of mass balance budgets for selected nutrients and chemicals.\nActivities planned in conjunction with NOAA's Manned Undersea Research\nand Technology Program in the Great Lakes include the following:\nMeasurement of in situ erosion rates and documentation of erosion and/or\ndeposition in time scales of weeks to months.\nCollecting core samples to determine the extent and cause of microscale\npatchiness in benthic distributions.\nDeterminations of the efficiency of the Ponar grab sampler.\n103","OCEAN AND GREAT LAKES SERVICES RESEARCH\nOcean and Great Lakes Services Research activities have focused on better\nunderstanding leading to improved prediction of phenomena involved with marine\nwarning and forecasting services. GLERL research includes field and analytic\ninvestigations of waves, flooding, water level oscillations, storm surges,\noverwater winds, and lake ice formation, growth, transport, and decay.\nResearchers in these areas work closely with colleagues at such agencies as\nNWS to assure that GLERL products meet the needs of operational forecasters.\nFollow-up on forecast accuracy and fine tuning of forecast procedures, in\ncollaboration with operational forecasters, are often included. GLERL scien-\ntists participate as representatives of NOAA and the Department of Commerce in\nregional, national, and international organizations addressing Great Lakes\nservices research problems.\nAccomplishments FY 1984\nA wind-generated wave prediction model has been developed theoretically\nand tested numerically against a 2-month data set from a GLERL tower and a\nNOAA Data Buoy Center (NDBC) NOMAD buoy in Lake Erie with remarkable agreement\nbetween observed and computed wave height (0.2-m rms error, 0.93 correlation\ncoefficient). Validation and comparison with NWS operational forecast proce-\ndures is under way. Interactive wave prediction software, implemented on the\nGLERL VAX computer, has been made available to five Great Lakes Weather\nService Forecast Offices to facilitate model validation as a local marine\nweather forecast tool. The response so far has been very favorable. A\nfurther test of the wave prediction system for a storm-generated synoptic wave\nfield in Lake Michigan observed by the NOAA aircraft/laser profilimeter also\nyielded remarkable agreement between model and observations for the total\nlake.\nAn analysis of 1981 NDBC data examines the various universal correlations\nof wave parameters that serve as the basis linking theoretical predictions to\nactual measurements. It was found that there are really no universal rela-\ntions per se among the parameters. Therefore, a model using one of the\navailable universal relations, as many numerical prediction models do, can be\nquite accurate at times and erroneous at other times. In practical applica-\ntions, the only correlation that shows consistency is that of nondimensional\nfrequency versus nondimensional energy.\nWe have used the 1981 Lake Erie coastal boundary layer experimental data\nto examine the probability distributions for both deep and shallow water\nwaves. Results show that both the Rayleigh distribution for wave heights and\nthe Longuet-Higgins distribution for wave period overpredicted the highest\nwaves in a record, and underpredicted the intermediate waves. By applying a\ntwo-parameter Weibull distribution to both height and period data and using\nparameters determined from the data, the accuracy of the fit was improved\nsignificantly.\nThe representation of shallow water wave spectra is another basic tool\nfor linking theoretical analysis with measurements. Earlier works simply\nmodified the deep-water saturation range exponent with an equivalent shallow-\n104","water exponent in the spectrum equation. A theoretical model developed by\nthe National Aeronautics and Space Administration (NASA) was examined; the\nagreement between the NASA model simulation and measurements is fair but not\noverwhelmingly good. However, when the GLERL generalized spectrum represen-\ntation is applied, the agreement between model results and measurement is\nexcellent. Thus, the GLERL model can be applied to both deep and shallow\nwater waves. Hence the spectral representation is independent of water depth.\nThe new spill model, PATHFINDER, has been made operational on the GLERL\nVAX 11/780 computer system. The initial design of GLERL's ice dynamics\nsimulation model is complete, and the model has been programmed on the VAX\ncomputer and the code tested for internal consistency.\nFour satellite-tracked buoys were deployed in ice in the central and\neastern basins of Lake Erie this past January. Flights were made every 2\nweeks to observe ice conditions and make ice measurements in the vicinity of\neach buoy. The tracks revealed continuous ice movement, often at surprisingly\nhigh speeds. Interpretation of ice movement will be aided by the ice recon-\nnaissance maps obtained from Canadian ice observers.\nThe record ice jam in the St. Clair River during April 1984 was observed\nand documented by aerial and ground reconnaissance. The field season of the\nSt. Clair River current meter program during winter 1983-84 was successful,\ndespite the record ice jam. The experimental measurement indicates that com-\nputed St. Clair River flows during ice conditions may be no better than those\nfor the Detroit River, contrary to previous assumptions.\nThe GLERL hydrologic response model was used to predict the impacts of\nthe record St. Clair River ice jam on lake levels and flows. The analysis and\nresults received nationwide attention.\nAn official NOAA atlas of Great Lakes ice, published by GLERL, will be\nthe standard reference on Great Lakes ice cover for some years to come. It\ndocuments important advances in our understanding of the Great Lakes ice cycle.\nAn analysis of the regional ice cover of Lake Erie relative to percentage\nice cover exceedance for discrete ice cover concentrations and discrete\nregions of Lake Erie was completed in 1983. The analysis was used by the\nNational Research Council in its study of the Lake Erie ice boom for the\nGLERL\nInternational Joint Commission.\nGLERL provided more than 4,200 research products in both Ocean and Great\nLakes Research and Assessment and Ocean and Great Lakes Services Research\nactivities in response to almost 2,000 documented requests. This was in addi-\ntion to regular mailings to those interested in receiving lists of publica-\ntions (every 6 months) and any of the five types of GLERL publications.\nPlans FY 1985\nThe GLERL wave prediction model will be modified for arbitrary water\ndepth, thereby making it applicable to nearshore coastal area wave predic-\ntions.\n105","A project synthesizing wind, wave, and temperature data recorded from\nNDBC NOMAD buoys will continue; it will be used for developing climatological\ninformation on Great Lakes waves.\nThe interactive version and the centralized computer version of the GLERL\nwave forecast model made available to NWS will be further tested for opera-\ntional use.\nWave characteristic measurements from a satellite-reporting wave buoy\nwill be compared with those from the NDBC NOMAD buoy in Lake Erie. These\nobservations will be used for further validation of the wave forecasting\nmodel.\nA complete review and possible extensive restructuring of the ice program\nwill be undertaken because of recent personnel changes. It is anticipated\nthat this activity will cover the period January 1985 to September 1985.\nAerial spectral reflectances will continue to be measured with a program-\nmable band radiometer. Most measurements will be spectral reflectances of\nvarious individual and composite ice types under clear skies.\nDigital imagery gathered by the NOAA-7/8 satellites will be geometrically\ncorrected and used for analysis of lakewide shortwave radiation reflectance\nfrom the ice cover. Identification of ice types in the imagery will be based\non large-area ice reflectance measurements.\nGround-based measurements of shortwave spectral reflectance of snow and\nfreshwater ice types will continue with modified instrumentation.\nA new field measurement program will be designed to assess the importance\nand extent of under-ice phytoplankton and zooplankton activity. The program\nwill involve the GLERL Lake Hydrology and Ecosystem and Nutrient Dynamics\nGroups.\nDevelopment of GLERL forecast models of thermal structure will continue.\nThese models simulate temperature decline and initial ice formation for Lake\nSuperior.\nFACILITIES\nTwo major types of compounds are analyzed by GLERL's chemistry labora-\ntories: trace synthetic organic materials and nutrients. The synthetic\norganics, primarily PAH, are extracted from various ecological matrices,\ncleaned, and analyzed on glass capillary gas chromatographs. These chromato-\ngraphs are currently being interfaced with GLERL's VAX 11/780 to upgrade data\nanalysis capability.\nThe uptake and release rates of selected PAH by benthic organisms are\nbeing followed through use of carbon-14- and tritium-labeled-compound metabo-\nlism. Compounds are extracted, cleaned, and counted by liquid scintillation.\nNumerous water samples from Lake Michigan were analyzed for various forms of\nphosphorus and silica and other water quality indicators as part of the Lake\n106","Michigan Ecosystem Experiment. The purpose was to define processes contri-\nbuting to phytoplankton dynamics, bacterial growth, and ecosystem carbon flow\nin Lake Michigan.\nThe biology laboratories' equipment and instrumentation include a multi-\nchannel Coulter Counter used to measure particle-size selection and zoo-\nplankton grazing on natural lake algae and seston. An array of instruments,\nincluding a liquid scintillation spectrometer, is used to investigate nutrient\nuptake, growth rates, competition for nutrients by algae, and cycling rates of\nselected algal nutrients. Facilities also include a full complement of\nsampling gear and instrumentation, growth chambers, stereo and inverted micro-\nscopes, and cultured populations of phytoplankton and zooplankton species for\nmodel studies. A mobile trailer has been fitted for lakeside investigations\nof the physiology and feeding rates of planktonic and benthic organisms.\nThe process of zooplankton feeding and other zooplankton/algal interac-\ntions occupies a central role in models of eutrophication and toxic organic\ncycling. Progress in developing mechanistic models has been hindered by the\ninability to observe the feeding process directly because of the small size\nof\nboth the zooplankton and algae and the high frequency (50 Hz) of zooplankton\nappendage movement. High-speed microcinematography was used to make the first\nobservations on these processes for a freshwater copepod. This was done at\nthe Skidaway Institute of Oceanography. We are now in the process of\nduplicating the microcinematography apparatus at Skidaway to study the feeding\nmechanisms of Great Lakes zooplankton in detail. A special feature of our\nlaboratory will be accurate temperature control.\nThe ice laboratory makes it possible to extend the winter measurement\nseason and to expand opportunities for measurements of ice characteristics\nThe facility consists of a work room and an ice storage room. The work\nroom, held at -7.0°C, can be used to conduct experiments on natural ice\nharvested in previous field seasons, as well as to calibrate instrumentation\nfor the ice research program in an environment similar to that encountered\nin the field.\nNatural and artifically produced radionuclides introduced into the Great\nLakes serve as excellent model contaminant and process indicators.\nThe particle dynamics laboratory can be used to detect and measure very low\nlevels of many such radioactive substances present in water, sediment, and\nbiota. The laboratory was established as part of the cooperative program with\nGLERL\nthe University of Michigan's Great Lakes and Marine Waters Center.\nThe GLERL computer facility supports data acquisition, data reduction,\ngraphics, and modeling applications for scientists and technicians in the\nresearch groups. A VAX 11/780 superminicomputer supports general purpose\napplications (e.g., graphics, data reduction and analysis, modeling, word pro-\ncessing), and a Hewlett Packard 9603 minicomputer supports data acquisition\ntasks. Within a year, a link to the National Bureau of Standards-ERL\nScientific Computing Facility in Gaithersburg, Md., will probably be\nestablished. The NBS facility will offer a very powerful computing capability\nthat will support GLERL modeling applications.\nThe R/V Shenehon is the primary platform used in support of open lake\nfield investigations. The vessel is 65.6 ft long, with a 6.5-ft mean draft, a\n107","600-nmi cruising range, and a 10-kn cruising speed. A hydraulic articulated\ncrane is used for deployment and retrieval of heavy instrument moorings.\nWinches handle hydrographic wire and multiconductor cable for sample casts and\nin situ measurements of water variables. An on board laboratory facilitates\nonsite physical, chemical, and biological experiments. A loran-C navigation\nsystem provides the capability and precision for the boat to return to an\nexact site in the lakes for equipment retrieval.\nThe marine instrumentation laboratory staff selects, calibrates, repairs,\nand, when necessary, adapts or designs instruments to collect data in the\nlakes and their environs. Engineers and technicians in this unit work closely\nwith GLERL researchers to ensure that instruments are compatible with the pur-\npose of the experiment.\nThe GLERL library staff supports laboratory activities by maintaining a\ntailored research collection and offering special retrieval services when the\ncollection cannot meet the documentation or information needs of the\nresearchers. The library collection consists of materials in the areas of\nclimatology, hydrology, hydraulics, ice, limnology, mathematical modeling,\nmeteorology, oceanography, sedimentation, and wave motion, with emphasis on\nthe Great Lakes Basin.\nINTERNATIONAL AND INTERAGENCY ACTIVITIES\nGLERL staff were active on several International Joint Commission boards\nand committees including the Levels and Flows Advisory Board; Technical\nInformation Network Board; Health of Aquatic Communities Work Group; Task\nForce for Lake Michigan Surveillance; Task Force for In-Place Sedimentary\nContaminants; the St. Marys, St. Clair, and Detroit Rivers and Lake St. Clair\nTask Force of the Surveillance Work Group; the Aquatic Ecosystem Objective\nCommittee Work Group; the Modeling Task Force of the Science Advisory Board;\nand the Lake Erie Task Force of the Surveillance Work Group.\nA GLERL staff member serves on the Natural Resources Management Committee\n(Subcommittee on Land and Air, Subcommittee on Water) of the Great Lakes\nCommission.\nGLERL staff participated in the activities of the International\nAssociation of Sediment Water Science, the International Coordinating\nCommittee on Great Lakes Hydraulic and Hydrologic Data, the Regional Response\nTeam for Spills of Oil and Hazardous Substances, Joint United States-Canadian\nIce Information Working Group, the International Association for Great Lakes\nResearch (President, Secretary), Science Education Administration of the U.S.\nDepartment of Agriculture, NOAA-U.S. Geological Survey Coordinating Committee\nfor Hydrologic Research, International Association for Hydrologic Research,\nthe Interagency Great Lakes Hydromet Steering Committee, and the National\nResearch Council Panel on Niagara River Ice Boom Investigations.\nThe Laboratory has recently become involved in an international (United\nStates-Canada) and interagency (United States: Environmental Protection\nAgency, NOAA, Corps of Engineers, Fish and Wildlife Service, Michigan\nDepartment of Natural Resources; Canada: Department of the Environment,\n108","Environmental Protection Service; Department of Energy, National Water\nResearch Institute; Inland Water Directorate; Department of Fisheries and\nOcean; Ontario Ministry of the Environment) multiyear study on water quality\nand marine pollution problems in the upper Great Lakes connecting channels\n(St. Clair River, Lake St. Clair, Detroit River, St. Marys River). The pri-\nmary marine pollution issues to be addressed are synthetic organic pollutants\nand nutrient overenrichment. A GLERL staff member is a member of a management\ncommittee developing a detailed study plan for the research and monitoring\nprogram.\nActivities involving participation with other NOAA units included the\nMarine Environmental Quality Task Force, Quality Assurance Working Group,\nManned Undersea Research and Technology Program--National Marine Fisheries\nService, New Bedford Harbor PCB Contamination Assessment Team, Marine\nEnvironmental Quality Review, and the Estuarine Review. GLERL staff par-\nticipated in several Sea Grant activities including the University of\nWisconsin Site and Subprogram (Microcontaminants) Reviews, and the Ohio State\nUniversity Site Review. In a joint program with the Ohio State Sea Grant,\nGLERL is developing a recreational planning guide for Lake Erie. GLERL has\nalso worked extensively with NWS and the Atmospheric Environment Service of\nCanada on an operational, interactive wave model.\nGLERL scientists were also active in providing information to several\nlocal agencies, such as the Kalamazoo River Preservation Agency and the\nTechnical Advisory Committee of the Huron River Watershed Council.\nGLERL\n109","","GEOPHYSICAL FLUID DYNAMICS LABORATORY\nJerry D. Mahlman\nActing Director\nPrinceton, New Jersey\nDirector\nO/P\nDep. Director\nCooperative\nESG\nWRP PROFS WMP\nInstitutes\nCRP\nGFDL\nNSSL\nWPL\nAOML\nPMEL\nGLERL\nARL\nSEL\nAL\nThe Geophysical Fluid Dynamics Laboratory (GFDL) is engaged in comprehen-\nsive long-lead-time research fundamental to NOAA's mission. The goal is to\nexpand the scientific understanding of the physical processes that govern the\nbehavior of the atmosphere and the oceans as complex fluid systems. These\nfluids can then be modeled mathematically and their phenomenology studied by\ncomputer simulation methods. In particular, GFDL research concerns the\nfollowing:\nPredictability of weather, large and small scale.\nStructure, variability, predictability, stability, and sensitivity of\nclimate, global and regional.\nStructure, variability, and dynamics of the ocean over its many space and\ntime scales.\nGFDL\nInteraction of the atmosphere and oceans; how the atmosphere and oceans\ninfluence and are influenced by various trace constituents.\nEarth's atmospheric general circulation within the context of the family\nof planetary atmospheric types.\nThe scientific work of the Laboratory encompasses a variety of\ndisciplines: meteorology, oceanography, hydrology, classical physics, fluid\ndynamics, chemistry, applied mathematics, and numerical analysis. Research is\nfacilitated by the Geophysical Fluid Dynamics Program, which is conducted\ncollaboratively with Princeton University. Regular Princeton faculty, visit-\ning scientists, and graduate students participate in theoretical studies, both\nanalytical and numerical, and in observational experiments, in the laboratory\nand in the field. The program is supported, in part, by NOAA funds. Visiting\nscientists may also be involved in GFDL research through institutional or\ninternational agreements, or through temporary Civil Service appointments.\n111","WEATHER SERVICE\nDuring the past two decades synoptic-scale weather forecasts have im-\nproved considerably because of the development of numerical models that in-\nclude more of the physical processes of the atmosphere, that have high spatial\nresolution, and that parameterize turbulent processes more accurately. Suc-\ncessful forecasts for periods up to a few days are now possible, and the lim-\nits of atmospheric predictability have been extended to several weeks; how-\never, quantitative precipitation forecasts remain elusive. For smaller spatial\nscales, there has been considerable progress in determining the mechanisms\nthat generate severe storms, in explaining how mesoscale phenomena interact\nwith the large-scale flow, and in simulating the genesis, growth, and decay of\nhurricanes.\nThis success in the extension of atmospheric predictability encourages us\nto pose more challenging questions. Can the weather be predicted on time\nscales of months? Are mesoscale weather systems and regional scale precipita-\ntion patterns predictable, and if so, is the accuracy dependent on the predic-\ntion of the ambient synoptic flow? Research to develop mathematical models\nfor improved weather prediction will also contribute to the understanding of\nsuch fundamental meteorological phenomena as fronts, hurricanes, severe storms,\nand tropospheric blocking.\nAccomplishments FY 1984\nMonthly forecast experiments, carried out for eight January cases with a\ngeneral circulation model (GCM) incorporating GFDL \"E-physics\", show that\nmonthly forecasts appear feasible, though the current skill is marginal. The\nskill scores for 1000-mb geopotential height are higher than those for 500-mb\nheight for all cases.\nThe GCM's with refined subgrid-scale parameterizations exhibit improved\noverall performance of monthly forecasts. The refined physics increases the\ncapability of simulating blocking ridges and improves the prediction of geo-\ngraphical locations of planetary-scale waves. It is also revealed that the\nroot-mean-square geopotential height errors have distinct geographical distri-\nbutions with respect to the models, and that these errors consist mostly of\nthe climatic drift of the respective models. This suggests that further ad-\nvances in monthly forecasting skill can be expected.\nA theory of the baroclinic instability of a zonally varying flow has been\ndeveloped. This theory has implications for the relation of the positions of\nstorm tracks to the large-scale planetary wave pattern, and for the role of\ntransient eddies in the maintenance of large-scale anomalies.\nThe continuous data insertion method in the four-dimensional data as-\nsimilation has been improved by applying a linear normal mode initialization\nto the injected data and using a wider range of data collection for deter-\nmining insertion data. There is an indication that such analysis improvements\ncan yield improved long-range forecasts.\n112","The effects of a long mountain range on a landfalling hurricane were\ninvestigated. The mountain affects the distributions of the low-level wind\nand the precipitation intensity to a significant degree. The decay rate of\nthe storm is increased as compared with a case excluding the mountain effects.\nThe enhanced decay was associated with reduction of the convergence of latent\nand kinetic energy during the storm's passage across the mountain range. The\nmean easterly flow, which carried a vortex, was notably modified by the moun-\ntains to influence the movement of a storm. This result adds another\ncapability in the requirements for significant improvements in hurricane fore-\ncasting skill.\nA study on the evolution of a real hurricane was initiated with the pre-\nparation of a numerical model and real initial data. Hurricane David, 1979,\nwas chosen for the first experimental case, and initial fields were retrieved\nfrom the FGGE level III-B data set produced at GFDL. This is the first effort\nat GFDL to explore forecasting skill for real hurricanes.\nSimulations of an isolated shower cloud of 1 hour duration have been\ncarried out with periodic and open lateral boundary conditions, with similar\nresults. Using a continental sounding for moisture and temperature, a strong\nsingle cell develops which gives maximum precipitation of approximately 1.0 cm\nin rainfall lasting for one-half hour. The simulations indicate a significant\nmodel net vertical momentum flux which is downgradient in all instances. This\nsuggests that GCM parameterizations of moist convection should include the\neffect of vertical momentum transfer.\nTwo independent numerical simulations of the evolution of realistic cold\nfronts indicate that latent heat released by moist convection substantially\nmodifies the larger scale frontal circulation.\nSimulations with the GFDL high-resolution mesoscale model have been car-\nried out to assess the impact of initial and boundary data inaccuracies on the\nsimulation of Meso-Convective Systems (MCS's) and their environments. It was\nfound that in most MCS's, the environmental convergence of a pre-existing\nfront was responsible for the growth of the storm vorticity, whereas latent\nheat release was required to produce explosive storm growth.\nA meso-beta scale simulation of an MCS over Oklahoma and Texas has pro-\nduced a realistic simulation of precipitation and cloud patterns during the\nperiod 10-11 April 1979. It was found that insertion of observed wind and\ntemperature data in the initial and boundary conditions had a major impact in\nGFDL\nthe simulation.\nA 48-h simulation using a limited-area model nested in a global spectral\nmodel seems to have captured the explosive behavior of the Presidents's Day\nsnowstorm (19-29 February 1979). The model data are now being analyzed to\ndetermine the mechanisms that led to the explosive storm growth.\nPlans FY 1985\nThe effect of sea surface temperature anomalies on monthly forecasts will\nbe investigated.\n113","Nonlinear eddy fluxes of heat and momentum associated with local baro-\nclinic instability will be derived. Local instability of realistic flows will\nbe analyzed.\nThe newly designed hurricane model will be used to investigate the devel-\nopment processes of Hurricane David.\nInvestigations of the role of latent heat in frontogenesis will continue.\nDetailed analysis of simulations of SESAME-I mesoscale convective systems\nwill be carried out.\nInvestigations on the numerical simulation of deep continental convection\nwill continue.\nCLIMATE\nThe purpose of climate-related research at GFDL is twofold: to describe,\nexplain, and simulate climate variability on time scales from seasons to mil-\nlenia; and to evaluate the climatic impact of human activities such as the\nrelease of CO2 and other gases in the atmosphere. The phenomena that are\nstudied include large-scale wave disturbances, with period of a few weeks, and\ntheir role in the general circulation of the atmosphere; the seasonal cycle,\nwhich must be defined before departures from it (interannual variability) can\nbe understood; interannual variability associated with phenomena such as the\nEl Niño/Southern Oscillation; very-long-term variability associated with the\nice ages; and the meteorologies of various planets, the study of which en-\nhances our perspective on terrestrial meteorology and climate. To achieve\nthese goals, both observational and theoretical studies are necessary: Avail-\nable observations are analyzed to determine the physical processes by which\nthe circulations of the oceans and atmospheres are maintained; and mathemati-\ncal models are constructed to study and simulate the ocean, the atmosphere,\nthe coupled ocean-atmosphere-cryosphere system, and various planetary atmos-\npheres.\nAccomplishments FY 1984\nA higher resolution (3° latitude) version of the GFDL \"SKYHI\" general\ncirculation model has been integrated for more than 18 months. The improved\nhorizontal resolution has led to a number of improvements in the simulated\ncirculation. Specific improvements include tropospheric zonal winds and jet\nstream; planetary wave amplitudes and propagation to the stratosphere; onset\nof sudden stratospheric warmings; and a reduction in the model tendency to\nyield excessively cold stratospheric winter polar regions. These improvements\nallow a more detailed look into the model dynamics as well as into model sen-\nsitivity to climatic perturbations.\nWork is under way on the effect of smaller scale gravity waves on plane-\ntary waves in the stratosphere and mesosphere. Early results from this work\nindicate that such interactions produce an important mechanism for mechanical\n114","planetary wave energy. This discovery has important implica-\ndissipation\nof\ntions for our understanding of dynamics and transport in the middle atmos-\nphere.\nAn attempt has been made to simulate the climate of the last glacial\nmaximum by use of a general circulation model of the atmosphere coupled with a\nmixed-layer model of the ocean. Given the distributions of continental ice\nsheets, surface albedo, and the reduced CO2 concentration of the ice age, the\nmodel generates sea surface temperatures that compare favorably with the sea\nsurface temperature at the last glacial maximum as reconstructed by geolo-\ngists. When the same model is used for the study of the anticipated climate\nchange due to a doubling of CO2, it yields an increase of global mean surface\nair temperature of 2.2°C.\nIt has been pointed out that the concentration of atmospheric carbon\ndioxide during the late Cretaceous epoch was several times higher than the\nmodern concentration. To evaluate the climatic consequences of large changes\nin atmospheric CO2, numerical experiments were conducted for a wide variety of\nCO2 concentrations (150 to 2400 ppm by volume) using a coupled ocean-atmos-\nphere GCM with idealized geography. According to the results from these\nexperiments, the high-CO2 world is characterized by high surface-air temper-\nature with small meridional gradients, high deep-sea temperature, an\nintense hydrologic cycle, and large poleward moisture transport. These\nresults suggest significant progress toward explaining the large differences\nbetween Cretaceous and contemporary climates. Moreover, they add credibility\nto current concerns on the possible climate impact of increasing CO2.\nNumerical experiments are nearing completion that test the sensitivity of\nan idealized nine-level GCM to large decreases in the solar constant. The\nqualitative dependence of sensitivity to solar constant changes has some simi-\nlarity to previously published results with a two-level model, which differed\nsignificantly from the results predicted by the commonly used simple energy\nbalance models.\nWork is continuing on the comparison of stationary eddies produced by\nGCM's and eddies predicted by a linear model based on the primitive equations.\nIt has been demonstrated that a useful first approximation to the stationary\neddy field in the extratropical upper troposphere can be obtained with such a\nlinear model. This suggests that significant improvements in the theoretical\nunderstanding of stationary eddies in the atmosphere may be forthcoming.\nGFDL\nAn analysis of the structure of stationary Rossby waves in vertical shear\nhas been completed. It explains why the response to stationary forcing in the\ntroposphere is equivalent barotropic far from the source and why there tends\nto be a maximum in geopotential amplitude near the tropopause.\nCalculations with an idealized two-layer quasi-geostrophic model show\nthat the eddy heat and potential vorticity fluxes increase much less rapidly\nas the meridional extent of the unstable region increases than is predicted\neither by weakly nonlinear theory or by the popular \"baroclinic adjustment\"\nhypothesis.\nSpectral analysis of results from GCM calculations indicates that sta-\ntionary ultralong waves gain kinetic energy but lose available potential ener-\ngy through the nonlinear interaction with transient waves. This loss is much\n115","larger than the gain and is compensated by a zonal-to-eddy conversion of avail-\nable potential energy.\nCalculations of infrared radiative cooling rates using line-by-line\nmethods have begun. These will be used as international standards against\nwhich the results of the parameterized algorithms employed in GCM's can be\ncompared. This is part of the WMO-sponsored International Comparison of Radi-\nation in Climate and Circulation Models.\nTwo extensive tape libraries with global atmospheric and oceanographic\nanalyses were prepared for distribution to the scientific community by the\nNational Climatic Data Center and the National Oceanographic Data Center,\nrespectively.\nAn extensive compilation of monthly general circulation statistics based\non the FGGE level III-B analyses produced at GFDL and a comparison with the\nanalyses by the European Center for Medium-Range Weather Forecasting for the\nSpecial Observing Periods were documented.\nA 15-year GCM run with changing sea surface temperatures prescribed\naccording to observations in the Pacific between 30°S and 30°N gave an\nexcellent simulation of El Nino/Southern Oscillation phenomena in the\natmosphere, especially in the tropics. This result lends optimism that pro-\nperly coupled atmosphere-ocean models will be able to simulate these pheno-\nmena. The observed anisotropy in transient disturbances with various time\nscales was found to be an important factor in determining the nature of the\nlocal exchange of kinetic energy between eddies and the time-mean flow.\nIn order to balance the poleward flow of atmospheric angular momentum, it\nwas concluded from observational calculations that the return flow of angular\nmomentum from middle to low latitudes does not occur in the oceans. Thus, by\ninference it must occur in the solid earth.\nObservational evidence was found for a meridional divergence or source of\nwater vapor over land as well as both oceans in the subtropics of the Northern\nand Southern Hemispheres. This \"land source\" of water is supplied by eastwest\nconvergence from the oceans.\nThe birth of Jupiter's Great Red Spot (GRS) has been simulated by a model\nthat describes the weak solitary barotropic instabilities that act at the\nlarge planetary scales. The longevity of the GRS has been simulated by a\nlarge vortex that appears to last indefinitely.\nPlans FY 1985\nThe basic 15-year (1958-1973) and FGGE (1979) data sets will be used to\nevaluate regional balances of angular momentum, energy, and water vapor.\nThe FGGE analyses generated at GFDL will be used in a study of the diur-\nnal cycle of the atmosphere.\nModel simulations of meteorological phenomena accompanying the El Niño/\nSouthern Oscillation will be compared with observation.\n116","A global model of the coupled ocean-atmosphere system with high computa-\ntional efficiency will be constructed for the study of climate sensitivity.\nThe performance of this model will be tested extensively.\nEfforts to identify and isolate the causes of systematic biases in cur-\nrent spectral and finite difference general circulation models will be under\nway, with continued emphasis on improvements in model physical processes.\nThe study of the transient and equilibrium response of climate to an\nincrease of atmospheric carbon dioxide will be continued by use of a coupled\nocean-atmosphere model with limited computational domain and idealized geo-\ngraphy.\nThe influence of cloud radiation feedback processes upon the sensitivity\nof climate will be investigated by use of a global atmospheric GCM coupled\nwith a mixed-layer ocean model. With a similar coupled model, additional\nnumerical experiments will be conducted and analyzed to identify the physical\nfactors responsible for the cold climate of an ice age.\nAnalyses of the albedo-feedback experiments with an idealized GCM will\ncontinue. Attention will be focused on the factors that determine how far\nequatorward the snowcover boundary must be before the model experiences a\nrapid increase in sensitivity.\nStudies with linear primitive equation models on a sphere will continue.\nThe extent to which the linear model can simulate the seasonal cycle in plane-\ntary wave structure will be examined. An attempt will be made to simulate the\nextratropical anomalies in extended GCM integrations with observed Pacific sea\nsurface temperatures (SST's) The same GCM integration will be used to test\nthe ability of a simple linear viscous model of the low-level tropical flow to\nsimulate the anomalous flow due to SST anomalies in the Pacific.\nSimple linear and nonlinear models of the tropical upper tropospheric\nflow and interactions between this flow and extratropical eddies propagating\ninto low latitudes will be examined, with particular attention to the possibil-\nity of reflection of incident Rossby waves by tropical winds.\nA space-time spectral analysis will be made of the low-frequency oscil-\nlations in the tropics simulated by a spectral general circulation model. A\nset of experiments will be made by the use of a simplified general circulation\nmodel to study the effects of transient waves on the zonal mean flow in the\nGFDL\npresence of surface friction.\nThe results of the International Radiation Model Comparison study will be\nanalyzed, with the goal of improving the radiative parameterization in GFDL\nGCM's.\nAnalysis will be under way on the dynamical behavior of the (3° resolu-\ntion) SKYHI model including sudden stratospheric warming diagnosis, impact of\ngravity waves on planetary waves, and identification of satellite sampling\nerrors.\n117","ATMOSPHERIC QUALITY\nThe main goal of Atmospheric Quality Research at GFDL is to understand\nthe formation, transport, and chemistry of atmospheric trace constituents.\nSuch understanding requires judicious combinations of theoretical models and\nspecialized observations. The understanding gained will be applied toward\nevaluating the sensitivity of the atmospheric chemical system to human activ-\nities.\nOngoing work that will be completed within the next 5 years includes\nanalyses of atmospheric nitrous oxide, reactive nitrogen (natural plus anthro-\npogenic), and tropospheric ozone. Capability will be developed to solve for a\nnumber of trace constituents simultaneously; then interdependent experiments\nwill be run involving ozone and its precursors, partitioned components of\ntotal reactive nitrogen, carbon monoxide, etc. Also, development of a dynam-\nically active ozone photochemistry will be completed for inclusion in the GFDL\ntroposphere-stratosphere-mesosphere (SKYHI) GCM. In addition, this model will\nbe developed for passive tracer studies.\nAccomplishments FY 1984\nA simple model has been developed that illuminates the mechanisms leading\nto the observed poleward-downward meridional slopes of stratospheric trace\nconstituents. In particular, the quantitative role of chemical processes in\n\"flattening\" these slopes has been clarified. The theory also predicts the\nway that the global average vertical \"eddy diffusion\" coefficient varies as a\nfunction of chemical sources and sinks.\nBy keying off the above results, a simple model has been developed that\npredicts the structure of trace constituent temporal variability, given a\nparticular chemistry. These two results allow the possibility of predictions\nof time mean and variable trace constituent structure, given such knowledge\nfor one constituent and the appropriate chemistry for any other constituent.\nIf such predictions prove to be valid upon observational testing, the problems\nof modeling systems with many species should be substantially simplified.\nThe vertical mixing of a passive tracer initially confined to the bound-\nary layer has been examined. For long-lived convection a well-defined inflow-\noutflow circulation develops so that mixing through a depth of 5 km is much\nstronger than for a short-duration shower cloud. Tentative results show small\nmixing to the upper troposphere. A primary conclusion is that vertical mixing\nappears strongly dependent on the duration of the convective cells.\nPlans FY 1985\nEfforts will continue on the \"combustion nitrogen\" and \"tropospheric\nozone\" series of numerical experiments, with emphasis on greater realism.\nWork will be initiated on multiple, interactive trace constituent modeling.\nA more detailed analysis of the convective transport of a passive tracer\nwill be under way, with an exploration of the effects of including water-solu-\nble trace gases.\n118","MARINE QUALITY\nResearch at GFDL related to the quality of the marine environment has as\nits objective the simulation of oceanic conditions in coastal zones and in\nestuaries, and the modeling of the dispersion of geochemical tracers (tritium,\nradon, etc.) in the world oceans. Over the next few years, two- and three-\ndimensional models of estuaries such as the Hudson-Raritan and Delaware\nEstuaries will be developed. The response of coastal zones to transient atmos-\npheric storms, and the nature of upwelling processes (which are of great im-\nportance to fisheries), are being studied by means of a variety of models.\nAccomplishments FY 1984\nA time-dependent carbon cycle model has revealed that the response time\nof atmospheric carbon dioxide to changes in the oceanic circulation is about\n200 years. This discovery may explain the low amounts of carbon dioxide dur-\ning the last ice age, as well as providing an important feedback mechanism on\nthe current increase in carbon dioxide from use of fossil fuel.\nAnalysis of transient tracer data and supporting modeling efforts have\nshown that seasonal convection and isopycnal mixing dominate over Ekman pump-\ning in thermocline ventilation. This suggests that seasonal and high-latitude\nprocesses must be especially accurate to produce good simulations of oceanic\ntracer transport.\nPlans FY 1985\nWork on the global carbon cycle will be extended by combining the exist-\ning geochemical model with a detailed three-dimensional model of the ocean\ncirculation.\nOCEAN SERVICES\nVarious models that can be used to predict oceanic conditions are being\nGFDL\ndeveloped at GFDL. The simpler models are capable of predicting relatively\nfew parameters. For example, one-dimensional models of the turbulent surface\nlayer of the ocean predict the sea surface temperature and heat content of the\nupper ocean. More complex three-dimensional models are being developed to\nstudy phenomena such as the time-dependent development of Gulf Stream meanders\nand rings, the generation of the Somali Current after the onset of the south-\nwest monsoons, the response of coastal zones to atmospheric storms, and the\ndevelopment of sea surface temperature anomalies such as those observed in the\ntropical Pacific Ocean during El Niño/Southern Oscillation phenomena.\nAccomplishments FY 1984\nA high-resolution model of the tropical oceans has been developed and\nused for realistic simulations of the seasonal cycle in the tropical Atlantic\n119","and of the 1982-1983 El Niño event. Of particular interest is the result that\nan intensification of the North Equatorial Countercurrent, between 5°N and\n10°N, was responsible for a large part of the eastward transfer of warm sur-\nface waters in the Pacific in 1982 and 1983. This result, using observed\nsurface winds for forcing, offers encouragement that properly coupled atmos-\nphere-ocean models may successfully simulate the El Niño phenomenon.\nAn eddy-resolving model of the ocean including the effects of both wind\nand thermal driving has been developed. An analysis of the solutions shows an\nextensive mixing along isopycnal (constant density) surfaces. This process is\nabsent in lower resolution models. Eddy transport of heat is a small, but\nsignificant component of the total poleward heat transport by ocean currents.\nThis has an important bearing on the design of ocean models for climate stu-\ndies. The model indicates that, in contrast to heat transport in the atmos-\nphere, oceanic eddy heat transport may be largely equatorward rather than\npoleward.\nNew observational evidence was found for the reality of a large annual\ncycle in the oceanic heat transport.\nPlans FY 1985\nDetailed comparisons between measurements of the seasonal cycle in the\ntropical Atlantic and model simulations will be undertaken.\nThe mass and heat budgets of the seasonal cycles of the tropical Atlantic\nand Pacific Oceans, and of the 1982-83 El Niño event, will be studied to deter-\nmine how heat and mass transports in the ocean change seasonally and inter-\nannually.\nThe resolution of the global general circulation model will be improved,\nand tests carried out to determine the rate of water mass formation.\n120","Edwin Kessler\nNATIONAL SEVERE STORMS LABORATORY\nDirector\nNorman, Oklahoma\nDirector\nO/P\nDep. Director\nCooperative\nESG\nInstitutes\nCRP WRP PROFS WMP\nAL\nSEL\nAOML\nPMEL\nGLERL\nGFDL\nNSSL\nWPL\nARL\nThe National Severe Storms Laboratory (NSSL) supports NOAA's weather\nobserving and forecasting missions through studies of storm processes, numer-\nical and conceptual modeling of storm phenomena, and development of improved\nmeans for observation. The NSSL mission has changed little over the years,\nbut approaches have changed considerably in response to new technological\ndevelopments, new scientific discoveries, and new requirements. Recent empha-\nsis has been on Doppler radar applications and studies of storm electricity.\nThe Laboratory has a 50-station capability for digital recording of\nsurface meteorological parameters, and maintains instrumentation on the tall-\nest tower in the United States that is equipped for recording boundary layer\nparameters. Two 10-cm Doppler radars on 41-km baselines provide unique capa-\nbilities for recording atmospheric circulations both in precipitating weather\nsystems and the optically clear boundary layer. A comprehensive range of\ninstrumentation for measuring parameters of both in-cloud and cloud-to-ground\nlightning has been brought to a high peak of refinement so that distributions\nof wind, water substance, and lightning can be recorded contemporaneously, and\nNSSL\ntheir interaction examined. A program of storm observing is conducted annu-\nally during the spring season, and typically involves groups representing\nabout 20 different organizations.\nThrough numerous relationships with other government agencies and univer-\nsities, NSSL constitutes a resource for severe-storm data examined by\nresearchers around the country and overseas. NSSL also participates in worthy\nprojects outside of Oklahoma. Thus, the NSSL staff was the coordinative focus\nfor a course on mesoscale meteorology offered in Boulder, Colo., and attended\nover a period of two weeks by 177 persons from many places and organizations.\nThe NSSL staff also had key roles in experiments at the Langmuir Laboratory in\nN. Mex., and participated in an experiment managed by the Boulder-based\nProgram for Regional Observing and Forecasting to evaluate displays of Doppler\nvelocity and reflectivity as part of the severe-weather warning process. One\n121","of NSSL staff was a member of the NOAA Natural Disaster Survey Team that\ninvestigated the Carolinas tornado outbreak of 28 March 1984. Finally, the\nLaboratory is working closely with the Joint System Program Office (JSPO) of\nthe Next-Generation Weather Radar (NEXRAD) program to help develop an\neffective national weather radar network for the late 1980's and beyond.\nDuring the past year, Laboratory scientists have produced new storm fore-\ncast techniques, and new methods for diagnosis and analysis of thermodynamic\nfields in storms as presented in a variety of reports and publications. In\ntwo books NSSL has contributed an advanced text on weather radar and a compre-\nhensive survey of the thunderstorm in its relationship to the social organism.\nMETEROLOGICAL RESEARCH\nThe Meteorological Research Group seeks to improve thunderstorm forecast\nand warning capabilities by developing conceptual, numerical, and laboratory\nmodels of major thunderstorm phenomena and of the prestorm atmosphere.\nAnalysis and interpretation of storm flow fields expand our understanding of\nexternal and internal forcing, thermodynamics, cloud physics, and cloud dynam-\nics, which contribute to intense thunderstorms and their attendant phenomena.\nSubsets of the group objective are addressed by two projects: Modeling and\nDynamics, and Storm Evolution and Analysis.\nAccomplishments FY 1984\nMICROPHYSICAL PROCESSES IN STORMS\nInsights into thunderstorm processes including hail growth, separation of\nelectrical charge, and production of heavy rainfall emerge from a clear under-\nstanding of the physics of water substance in clouds. A new diagnostic model\npresents microphysical and thermal variables within observed thunderstorms.\nThe model proceeds from Doppler airflow measurements and an environmental\nsounding through the relevant thermodynamic and microphysical processes to\ncalculate fields of potential temperature and water vapor, and concentrations\nof both liquid water and ice within storms. The diagnosed internally consis-\ntent storm structure reveals influences on precipitation cores by recycling of\nmillimeter-sized ice, graupel, and droplets as well as the larger influences\nof transport processes on larger scales. The calculations, known as micro-\nphysical retrieval, also help identify errors in analyzed fields. When\nobserved and retrieved radar reflectivities are compared, localized bias\nerrors in wind analysis are sometimes suggested. These biases lead to anoma-\nlous precipitation content and thermal structure via the continuity principles\nwithin the model. When the wind field errors are corrected, the resulting\nimplied and observed reflectivities are in much better agreement.\nStudies of hail growth with Doppler-derived wind fields, a numerical\nmodel, and information from surface hailstone collection help to reveal how\nhail growth is related to storm structure, intensity, and evolution. Analysis\nof hailstone structure revealed that almost all growth was in the wet mode,\nnot all the undercooled liquid water accreted by the growing hailstone\n122","froze immediately on contact. The model results indicate that two major\ngrowth trajectories existed in the storm, and that the fall-out position of\none trajectory coincided with hailfall position as documented from a collec-\ntion vehicle. In agreement with the results of the hailstone structure analy-\nsis, all the mass of the modeled hailstones that fell in the collection area\nwas accreted in the wet mode; this growth in the model occurred at ambient\ntemperatures at or above -17°C.\nThe microphysical structure and general evolution of storms can be stud-\nied with Doppler velocity spectra collected at vertical incidence. A new\ntechnique using such spectra acquired at two radar wavelengths provides more\naccurate estimates of air velocity and drop size distribution. The technique\nmust be applied with cautious attention to hardware quality and configuration,\nsince accuracy in estimates is very sensitive to data quality.\nTORNADIC STORMS\nImproved understanding of the fields of velocity, pressure, temperature,\nand water quantities within tornadic storms should lead to greater understand-\ning of tornadogenesis and ultimately to improved warning criteria. Data from\nthe tornadic Binger, Okla., storm of 1981 have been analyzed to determine the\norigin of the \"echo-weak hole\" within the mesocyclone region. Following\ncalculation of the wind field from dual-Doppler radar data, a microphysical\nretrieval method has added information on the water and thermal fields. Major\nreflectivity features such as hook echo, main precipitation shaft, gust front,\ncell core, slanted reflectivity ridge from hook echo to gust front, and\nbounded weak echo regions are well retrieved in the model. Recycling of\nmillimeter-sized graupel and raindrops in the updraft seems important to the\nformation of the precipitation core. The echo-weak hole within the mesocy-\nclone is likened to a soda straw--rotation causes the sides to be impervious\nto radial influx, while the top and bottom of the tube draw in little precipi-\ntation because of low precipitation content and downward air motion,\nrespectively.\nA theoretical study of rotation in thunderstorms has shown that stream-\nwise vorticity, i.e., vorticity along the wind direction in the storm's refer-\nence frame, causes the updrafts of supercell storms to rotate cyclonically.\nStreamwise vorticity is present in the environment when the storm-relative\nwinds veer with height. Convection can generate vertical motions and vertical\nvorticity through a process represented by the tilting term in the vorticity\nNSSL\nequation, and updrafts are thereby caused to rotate cyclonically and down-\ndrafts anticyclonically when the storm-relative winds veer with height. The\ntheory has led to a technique for diagnosing storm severity from observations\non storm motion by radar or other means, and a nearby atmospheric sounding.\nMethods for retrieval of pressure and buoyancy have been applied to\nDoppler velocity data from the Del City tornadic storm (20 May 1977). The\ndirection of maximum pressure gradients across the updraft core in the pre-\ntornadic stage was in nearly the direction of the environmental wind shear\nvector at each altitude. In the tornadic stage a pronounced pressure minimum\n(~3-4 mb below ambient) coincides with the low-level mesocyclone. A pressure\ndeficit near the surface is induced by the strong cyclonic vorticity there--\nthis reverses the vertical gradient of perturbation pressure with sudden\n123","formation of the rear downdrafts commonly observed in tornadic thunderstorms.\nAn investigation using the same approach, applied to the tornadic storm of 8\nJune 1974, revealed pressure forces that create a flux of air parcels into\nthe mesocyclone from higher levels on the storm's rear. Downdrafts fill the\nmesocyclone in final stages, and updrafts weaken nearby.\nThe evolution of tornadic thunderstorms over northwest Oklahoma on 2 May\n1979 has been investigated using dual-Doppler radar observations. The advance\nof a rainy downdraft behind the Lahoma gust front stimulated low-level\nconvergence and development of a possible gust front tornado. Perturbations\nin the updraft and vertical vorticity produced the long-lived Lahoma mesocy-\nclone. Air parcel trajectories within the storms illuminate the process of\ndissipation of both the Lahoma mesocyclone and first Orienta tornado. The\ntrajectories during mature stages show air parcels entering from low levels\nand rising cyclonically within the mesocyclone updraft. Mesocyclone updraft\nseparation, downdraft infiltration, and vertical vorticity reduction are the\nmajor dissipative features of the Lahoma mesocyclone. The Orienta tornado\ndissipated as downdraft air reduced the buoyancy of the mesocyclone inflow.\nVisual and photographic observations of four tornadoes were made by\nintercept teams during NSSL's Spring Program. One was a cyclonic-anticyclonic\ntornado pair concurrently observed by Doppler radar. Attempts to deploy TOTO\n(Totable Tornado Observatory) in tornado paths were hampered by erratic tor-\nnado movement and abrupt changes in intensity.\nTHUNDERSTORM EVOLUTION AND STRUCTURE\nImportant forecast and warning insights are often gained by investigation\nof smaller convective entities because these sometimes evolve to produce or\nmaintain larger storm complexes. Doppler data collected on 19 June 1980\nreveal that a group of small cells evolved into an isolated supercell storm.\nThe storm initially propagated to the right of the mean wind, but as the size\nand intensity of the individual cells increased (and center-to-center spacing\nremained constant), the reflectivity structure appeared to become steady. The\nincrease in size and intensity was attributed to an increase in potential\nbuoyant energy in the storm inflow and a slight increase in the storm-relative\nvertical wind shear. During 2 1/2 hours of dual-Doppler data collection, maxima\nin reflectivity and updraft speed increased dramatically with transition to a\nsupercellular structure.\nA large squall line produced strong outflow winds, frequent cloud-to-\nground (CG) lightning, and locally heavy rainfall on 19 May 1977. Study has\nshown that small rain-producing cells preceding the line were an integral part\nof the line's mesoscale organization and contributed strongly toward maintain-\ning the intensity of preferred sections of the line. Description of this work\nalong with that of other recent and past work is included in a comprehensive\nreview of extratropical squall lines and rainbands.\nFORECASTS AND WARNINGS\nFor the past 12 years, NSSL has been informing the Oklahoma City National\nWeather Service Forecast Office (WSFO) of severe weather signatures that\n124","appear on Doppler radar displays at the Laboratory. During the 1984 spring\ndata collection period, color displays were transmitted of Doppler velocity\nfields with superposed lightning strike locations to the WSFO. This project\n(Project DOPLIGHT 1984) demonstrated effective transmission of combined\nDoppler and lightning data over a high-grade telephone line. The forecasts\nand warnings were significantly improved by the availability of processed\nDoppler radar and lightning data.\nA useful relationship has been found between maximum hailsize produced by\na storm and the strength of the single Doppler velocity signature of diver-\ngence near storm top. The relationship appears to hold great promise for\nhailstorm warnings by distinguishing between storms that produce very large\nhail (diameters of 7 to 10 cm) and those that produce relatively small hail\n(2 to 4 cm)\nAn atlas prepared at NSSL shows single Doppler velocity signatures as\naids to Doppler scope interpretation by radar operators. The signatures\ninclude simulated Doppler velocity patterns in the optically clear atmosphere,\nin widespread precipitation, and within severe thunderstorms. The idealized\nvelocity fields are shown to be good approximations to actual Doppler velocity\nmeasurements.\nSince NSSL's inception over 20 years ago, it has been actively involved\nin improving short-term storm warnings. Recently, we have been developing a\nmesoscale numerical forecasting model based on the Anthes-Warner (Penn State)\nmodel. Following comprehensive model testing, simulated data for a frontal/\ndry-line low-pressure situation have been used to initialize the model.\nResulting development of the subsynoptic low-pressure system is being\nevaluated.\nDATA ACQUISITION AND PROCESSING\nMultiple Doppler radar studies of severe thunderstorms during the past\ndecade have revealed many of their structural details that would otherwise\nhave remained unknown. Ability to follow evolving vertical velocity fields\nhas been especially revealing. However, researchers are starting to realize\nthat errors in the reconstructed vertical velocity components can be signifi-\ncantly greater than those explained theoretically from radar geometry. A\nstudy of potential error sources in actual data sets is showing that major\nerrors are not attributable to incorrect storm advection, incomplete sampling\nNSSL\nof low-level divergence, or large variance of Doppler velocities. Work is\ncontinuing in order to isolate and study other possible error sources.\nThe NOAA P-3 aircraft, equipped with a Doppler radar that scanned orthog-\nonally to the aircraft track, was flown in Oklahoma as part of the NSSL Spring\nProgram. Through the use of both ground-based and P-3 radar data, we expect\nto be able to document the life cycle of a tornadic storm that simultaneously\nproduced cyclonic and anticyclonic tornadoes observed also by storm intercept\nteams. In another case, in cooperation with NASA, data were collected simul-\ntaneously with downward-looking sensors on an aircraft at very high altitude\nand on the P-3. The in situ P-3 data will help calibrate the data obtained\nfrom higher altitude. Data gathered from a sea-breeze-induced storm in\nFlorida by the P-3 were analyzed to examine the sensitivity of the data to\n125","different analysis methods. The differences in the analyses could be\nexplained by statistical error propagation and effects of circulation changes\nwith time.\nRawinsonde measurements provide information important for storm forecasts\nand warnings to managers of weather observing programs. For several years,\nrawinsonde data acquired by Air Force and Army units have been sent by phone\nline from the field to NSSL where they have been plotted in a time consuming\nprocess. In 1984, data was transmitted directly to a minicomputer that\nplotted soundings automatically at NSSL. Raw data also were sent directly to\nERL's CDC 750 computer in Boulder for archiving.\nPlans FY 1985\nWork on the tornadic Binger storm will be extended, including investiga-\ntions into storm kinematics, dynamics, and microphysics.\nDoppler radar data from the 1984 Thunderstorm Research International\nProgram (TRIP) experiment in New Mexico will be analyzed. Microphysical\nretrieval experiments will be performed using high-resolution wind data\ncollected at frequent intervals, and diagnosed fields will be related to\nindependent aircraft and balloon observations.\nTheoretical investigations into the formation of mesocyclones will con-\ntinue.\nThe lifetimes of thunderstorm features as related to NEXRAD scanning\nstrategies will be examined in a report for FAA.\nFormal documentation of the 19 May 1977 squall line will completed, and\ndynamic retrieval experiments using data from the 20 May 1977 tornadic\nstorm will be documented.\nStudy of the Agawam, Okla., severe thunderstorm of 6 June 1979 is\nexpected to reveal the role that storm dynamics and kinematics play in\nthe storm-splitting process.\nThe mesoscale numerical model will be run using a case study for 9 May\n1979 as initial conditions. We expect to be able to determine local\nconvective forcing mechanisms and modification of the planetary boundary\nlayer. The first phase of initialization technique development for the\nmesoscale forecast model will be completed.\nAlgorithms for defining fine-scale atmospheric structure from combined\nrawinsonde and satellite radiance data will be applied with objective\nanalyses of radar data to a case study for 27 August 1982.\nExperimental design studies for sensor placement during STORM-Central\nfield experiments will be completed.\nThe field phase of a cooperative hailstorm investigation to use in situ\nmeasurements, surface hail collection, multiple Doppler radars, and\n126","numerical models is planned for Spring 1985. A major feature of the\nstudy is to initialize and check model results with actual in-cloud and\nsurface-collected hailstones.\nDOPPLER RADAR AND STORM ELECTRICITY RESEARCH\nThe NSSL facility to observe electrical and kinematical processes contem-\nporaneously with precipitation phenomena has no parallel. The major objectives\nof Doppler Radar and Storm Electricity Research (DRASER) include (1) determining\nrelationships between processes of lightning, thermodynamics, and precipitation\nin thunderstorms in order to develop improved indicators of thunderstorm\nseverity and hazards; (2) developing and refining remote-sensing techniques for\nlocating, tracking, and predicting thunderstorms and their attendant hazards;\n(3) defining lightning and kinematic characteristics of storms for inputs into\nengineering criteria for hazards to aircraft and ground facilities, and into\nmodels used in environmental studies; (4) providing ground truth and supportive\ndata for development of new instrumentation and refinement of observational\ntechniques.\nThese objectives are addressed through both theoretical and observational\nstudies. The Doppler Radar Group focuses its efforts on interpretation of\nprestorm and stormy weather phenomena, using Doppler radar data for both.\nThe\nStorm Electricity Group concentrates its analyses on data simultaneously\nobtained with Doppler radar and our many storm electricity sensors.\nAccomplishments FY 1984\nDOPPLER RADAR\nStorm Initiation\nAn analysis of convective development along a frontal zone (30 April 1981)\nhas demonstrated the utility of single Doppler radar in short-range fore-\ncasting. Winds obtained from single Doppler radar data using the Volume\nVelocity Processing (VVP) linear technique, under the assumption of uniform\nwind, compare quite well with rawinsonde measurements. The location of the\nfrontal zone aloft, clearly defined in the wind field, was coincident with a\nlayer of upward air motion measured from Velocity Azimuth Display (VAD) tech-\nniques. Storms developed with the onset of warm air advection and increased\nNSSL\nvertical motion, all of which were detected by radar. The locations of storm\nformation were displaced horizontally from the surface frontal position.\nHowever, the region where storms began and their subsequent motion could have\nbeen anticipated from a map derived from Doppler data analysis of frontal\nheight above ground and detailed thermodynamic analysis.\nPrestorm cloud formation has been related to boundary layer convergence\nin the vicinity of a dry line, 17 May 1981, with the cooperation of NASA\nGoddard Space Flight Center. A cluster of dense clouds and strong convergence\non a scale of 10 km precedes severe storm development by only about 30 min.\nMoreover, widespread vertical motion was not observed prior to this\ndevelopment.\n127","In general, Doppler divergence measured with data from a single radar has\nbeen found to agree well with dual Doppler analysis. However, the position of\ncumulus clouds is not always well correlated with convergence areas of the\nscale resolvable with the VVP analysis (~40 km). Research has begun into\nusing variance of radial velocities obtained from a single radar to estimate\nconvergence associated with the individual cumulus clusters. This affords\nmuch improved resolution over the linear wind methods. Early results are\nencouraging, and we anticipate developing this idea further in FY 1985.\nAnalysis of radar data has begun in order to examine the relationship\nbetween reflectivity and precipitable water in the boundary layer (using\nradiometer data from WPL). Data analyzed to date reveal an enhancement of\nreflectivity at the top of the mixed layer starting about noon. The enhance-\nment is attributed to intermittent mixing of cool moist air with warm dry air\nat the inversion. Both total precipitable water and reflectivity below the\ninversion increased steadily before the enhanced reflectivity was observed.\nWe are investigating how much of the increased boundary layer moisture can be\nattributed to latent heat flux (evaporation).\nEnhancement of Observing Capabilities\nA technique to whiten the sidelobe powers of an array antenna has been\nidentified. Its purpose is to reduce sidelobe interference with measurements\nof Doppler shifts in the mainlobe. The method employs antenna pattern switch-\ning so that, ideally, the sidelobes contribute incoherently to the Doppler\nspectral moements while the mainlobe power adds coherently. First calculations\nsuggest that the average nonwhite power residue in the sidelobes can be 14 dB\nbelow the average sidelobe power of an equivalent nonswitched pattern.\nFurthermore, it is shown that with additional signal processing the power from\nsidelobes can be filtered out.\nPerformance of a weather Doppler radar with a staggered pulse repetition\ntime has been compared theoretically with one using a random (but known) phase\nof the transmitted pulse. As a standard for this comparison, the specifica-\ntions of the forthcoming Next Generation Weather Radar (NEXRAD) have been used.\nRandom phase processing offers a better overall performance with an advantage\nof at least 13 dB in the removal of overlaid echoes. But the staggered scheme\nallows for automatic velocity dialiasing and should be much simpler to implement.\nThe effects of natural shields on Gaussian shaped antenna patterns have\nbeen quantified. The solution of ensuing diffraction integrals for the pattern\nshape is expressed in terms of complex error functions. It is shown that\nground clutter can be reduced by as much as 20 dB by proper choice of antenna\nsite. This finding has significance for radars that are meant to observe low-\nlevel wind shear in and around airports.\nTheoretical investigation of various schemes to obtain differential\nreflectivity has begun. We have found that switching between fields offset\nfrom the vertical by +45° and -45° provides considerable reduction of the dwell\ntime required for estimating differential reflectivity.\nA conceptual study of how to track balloons with a NEXRAD-type radar has\nbeen completed. It is suggested that computer-controlled scan over a small\n128","azimuth-elevation sector should produce good quality velocity estimates if echo\npower is fitted by a least-squares method to azimuth and elevation.\nWe are continuing to assess the accuracy of techniques that estimate the\nwind component transverse to the direction of a Doppler radar beam. For that\nreason we have examined Fourier spectra of mean Doppler velocity on a circle\ncentered at the radar. For a 50-km radius we have found that harmonics with\nwavelength less than 50 km are at least 60 dB below the longer wavelength\nharmonics.\nRadar-Lidar Investigation of Quiescent and Stormy- Weather\nA detailed comparison of wind fields obtained by an airborne Doppler lidar\nwith those synthesized from two Doppler radars has been completed. It was\ndetermined that errors in lidar-derived wind speed and direction came from a\nSchuler resonance in the inertial navigation system, which caused an erroneous\nindication of aircraft velocity perpendicular to the heading. This led to an\nerroneous subtraction from the lidar-measured radial velocities. When this\nSchuler resonance was accounted for, differences between lidar and radar\nindications were less than 0.75 m s-superscript(1). Lidar and single Doppler radar radial\nvelocities collected on another day agreed within 1 m S -1 through a full 360 o\ncircle around the Norman Doppler radar.\nResearch on the structure of the convective atmospheric boundary layer\nobserved with the instrumented NSSL/KTVY tall tower, airborne Doppler lidar,\nand ground-based radars established that the vertically averaged winds in the\nboundary layer are insensitive to baroclinicity, supporting a hypothesis\nadvanced in the literature in 1975. However, the computed momentum flux\nprofiles are affected by baroclinicity. A persistent spectral peak in the\nspectrum of turbulence observed with lidar, radar, and tower is consistent\nwith the presence of horizontally symmetric cells with a horizontal wavelength\nfour times the boundary layer height, as suggested by theory.\nReal-Time Weather Data Processing\nMuch of NSSL's work in this area relates closely to the NEXRAD project,\nwhereby a new national radar system for severe storm warning is to replace the\ncurrent WSR-57 radars toward the end of this decade. We have completed a\nprogram that displays heights of constant reflectivity, from which we identify\nNSSL\nareas of deeper convection (ADC) The locations of ADC are a basis for short-\nterm forecasts of convective precipitation.\nComputer software was developed to combine and compress Doppler velocity\nand lightning data so that their essence can be transmitted to users at the\nreasonable cost of a 9600-baud line. The DOPLIGHT data were displayed on a\ncolor terminal in the National Weather Service Forecast Office at Oklahoma\nCity and facilitated the warning process during severe storm episodes.\nAn algorithm to detect and track gust fronts has been developed and\ntested. The algorithm contains two procedures that operate independently on\nthe data. In one, locations of maximum radial convergence are detected and\ngrouped into gust lines, so that fronts with strong radial components can be\n129","identified readily. When fronts are aligned along radar radials, the\nmesocyclone-shear algorithm is used. Tracking with both procedures is accom-\nplished by least-squares fitting and projecting in time a second-order poly-\nnomial in range or angle. It seems possible to project the front's position\n10 min into the future with rms errors of only a few kilometers.\nGust Fronts and Downbursts\nA study of the symmetry of intense local downdrafts (downbursts) from\nconvective storms is under way. Several cases have been selected for detailed\nanalysis. A downdraft on 30 May 1982 was found to have a velocity change as\nlarge as 20 m s-1 over a distance of 1 km. The affected region was elongated\n(10 km X 5 km ellipse) and rotated cyclonically. On 17 May 1983, downdraft\nwinds were locally as strong as 35 m s-1 and shear was 3.75 X 10-3 s-1.\nInvestigation continues of several gust front episodes from 1982 through 1984.\nInitial inspection of some Doppler data point to a possible wave phenomenon at\nboth sides of the gust front. Rawinsonde and tower observations are used to-\ngether with vertical cross sections of reflectivity, velocity, and Doppler\nspectrum width to understand the structure of these fronts and waves.\nA feasibility study of a Doppler Downburst Detector has been completed.\nIt seems that a wide-beam radar scanning overhead could detect downward-moving\nair if spectral processing were utilized.\nThunderstorm Turbulence\nA study of the turbulent energy budget in a severe storm from its onset\nto maturity was completed, and various terms of the turbulent kinetic energy\nequation have been evaluated. From the time of the first echo, the average\nkinetic energy density increases considerably. Also, the total kinetic energy\nof the storm increases to a steady state value near the equivalent of 230 kt\nof TNT. We have found that convergence of the horizontal energy flux contrib-\nutes significantly to the energy change within the storm. Even though the\nstorm is evolving, the mean winds over the storm at various heights hardly\nchange from the environmental values over the period of observations.\nNASA Langley Research Center and NSSL are sharing 1981 Doppler radar and\nF-106 aircraft turbulence measurements. Two important conclusions have been\nobtained concerning radar estimates of turbulence based on the Doppler spec-\ntrum width. First, we have observed that Doppler spectrum widths are indepen-\ndent of the viewing angle of the radars; widths measured from two radars with\northogonal beams agree within 1 m s-1. Second, we have obtained extremely\ngood consistency between eddy dissipation rates calculated from the Doppler\nspectrum width and those estimated from the spatial spectra of mean velocities.\nAn investigation of the effects of a bilinear velocity height profile on\nthe Doppler velocity and spectrum width has been undertaken. Good agreement\nbetween the width predicted by this model and the measured spectrum width has\nbeen obtained.\nInvestigation into turbulence and the structure constant of refractive\nindex in a solitary wave has begun. Links between spectrum width measured by\n130","Doppler radar, vertical profiles of refractive index deduced from tall-tower\nmeasurements, and reflectivity have been established.\nData acquired in thunderstorm penetrations made by NASA F-106 and concur-\nrent Doppler radar have reinforced statistics showing a correlation between\nDoppler spectrum widths (second moment of the Doppler radial velocity) and\naircraft-measured turbulence.\nThe evolution of gust fronts and downdrafts is being studied to identify\nsource region and to determine if characteristics of areas where these phenom-\nena originate can be used to forecast the timing and magnitude of subsequent\nweather hazards.\nSTORM ELECTRICITY\nAssessment of Errors in Automatic Ground Strike Location\nUse of systems to locate ground strikes continues to increase rapidly\nwithin the continental United States. Since about two-thirds of our country\nis now covered by such systems, which are used daily, it is important to know\ntheir accuracy. We completed a study of systematic site errors in the NSSL\nsystem using both a simple statistical technique and comparison with actual\nground truth data for lightning at long ranges (200-300 km), obtained with the\nUniversity of Mississippi/NSSL mobile laboratory. We found site errors, i.e.,\nlocally caused errors in azimuths, of up to 12 degrees. We have successfully\ndetermined correction curves for our data collected prior to 1984.\nSystem detection efficiencies that are quite high have been reported, but\nundocumented, for ground strike locating systems. We have found that our\nsystem detects about 70% of flashes within 300 km. Although this is somewhat\nlower than reported elsewhere, it is more than adequate for many applications,\nsuch as storm tracking.\nMobile Balloon Flights to Measure Electric Fields\nUsing the mobile storm electricity laboratory and a second vehicle for\ntransporting and launching balloons in storm inflow regions, we joined with\nscientists from the University of Mississippi in developing storm intercept\nand balloon-launching techniques that now allow us to fly a series of balloons\ninto the same storm. These balloons are instrumented to measure electric\nNSSL\nfields in addition to the standard meteorological sounding parameters. A\nhalf-dozen successful flights were made into severe and tornadic storms during\nspring 1984 in an effort to learn about the distribution of storm processes\nand hazards within them.\nCloud-to-Ground and Intracloud Lightning in Tornadic Storms\nResearch continued on lightning rates in tornadic storms on 17 May 1981.\nIt was found that intracloud lightning rates are highest during the tornadic\nstage, but that cloud-to-ground (CG) lightning rates increase significantly in\nthe vicinity of the mesocyclone after the tornadic stage of a storm ended.\n131","This investigation extends and supports initial results of the research on\ntornadic storms that was begun with data collected on 22 May 1981.\nLightning and Vertical Storm Structure\nWe have continued our use of the 70- and 10-cm wavelength radars at\nWallops Island, Va., to investigate the distribution of lightning within thun-\nderstorms and squall line cells. The very long wavelength makes the 70-cm-\nwavelength radar unique for its ability to locate lightning even in intense\nprecipitation. By combining vertical scan data from both radars, we have\nfound that there are two centers of lightning activity, separated vertically.\nThe lower center is at about 6 km and the upper one at about 12 km. This is\nindependent corroboration of our conclusion reported last year of two such\nlightning \"cores\" in Oklahoma storms. New understanding gleaned from this\nstudy is being incorporated into operational procedures used in applied re-\nsearch on lightning hazards to aircraft.\nLightning Hazards to Aviation\nAs part of our continuing involvement in a joint program with other\nagencies and the National Interagency Coordinating Group (NICG) on atmospheric\nelectricity hazards, we have continued to make measurements of lightning\ninvolved in direct strikes to an instrumented NASA F-106B research aircraft.\nDuring this past year, we found that the F-106 always triggered lightning to\nitself and never intercepted an existing flash. Radar measurements of the\ndirect lightning strikes to the aircraft show that the channel usually propa-\ngates bidirectionally outward from the aircraft. This observation on light-\nning within storms is the first experimental evidence indicating that streamer\ndevelopment is not a unidirectional process as had been reported in some\nlaboratory studies.\nAnother aspect of our work with the NICG was to serve on the steering\ncommittee for organization of the 9th International Aerospace and Ground\nConference on Lightning and Static Electricity held in Orlando, Fla., in\nJune. There were approximately 60 papers presented and 330 registrants.\nEquipment Improvements\nIn response to discovery of large site errors in the NSSL CG ground\nstrike locating system, we moved the Norman site, which was the major contrib-\nutor to these errors. In addition, data acquisition and \"quick-look\" playback\nof the ground strike locations have been improved with additional hardware.\nA modification to the VHF lightning-mapping system was completed to allow\ncontinuous all-hemispheric mapping of lightning within storms.\nLightning Ground Strike Climatology\nA final report on lightning strike density in the United States was\ncompleted for the Nuclear Regulatory Commission. Thunderstorm duration data\n132","were compiled from 450 weather stations for a 30-year period, and lightning\nstrike data from Oklahoma and Florida were analyzed to determine a relation-\nship between thunderstorm duration and lightning strike density. The result-\ning maps of annual lightning strike density in the United States present\nsignificantly better estimates of strike density than similar maps based on\nthunderstorm-day data.\nPlans FY 1985\nIn order to develop improved operational capabilities for forecasting the\nlocations where storms develop and their intensity, we shall continue\nin-depth examinations of the prestorm radar data with other data sources\nand theory. Variance of Doppler (radial) velocity fields will be related\nto development of cumulus clouds.\nTo predict downdrafts and gust fronts, a study of their origin and\nevolution will continue.\nStudies of advanced techniques to reduce velocity and range ambiguities\nin Doppler radar will be conducted.\nWind-profiling capability of weather radars will be examined both theo-\nretically and experimentally.\nNEXRAD algorithms for detection and tracking of hazardous weather will be\nimproved.\nA polarization capability on the Cimarron Doppler radar will be imple-\nmented and signal-processing techniques to estimate differential reflec-\ntivity will be studied.\nRelationships between microphysical and electrical processes will be\nstudied using dual-polarized and vertical-pointing Doppler radar and\nelectrical measurements.\nThe VHF lightning-mapping system will be modified for greater simplicity\nand reliability in acquiring data of high quality.\nWe will continue to contribute to the NICG on atmospheric electricity\nNSSL\nhazards, including analysis of in-flight lightning strike data.\nWe will be analyzing physical characteristics of +CG flashes and analyz-\ning mesoscale and synoptic conditions associated with a storm having an\nunusually high percentage of +CG flashes.\nWe will complete analysis of flash rates and mesocyclone development for\ntwo tornadic storms and determine electric field profiles in different\nstorm areas and compare them with storm structure.\n133","COMPUTER AND ENGINEERING SUPPORT\nAND DEVELOPMENT\nThis group (CESD) develops techniques and equipment, maintains observa-\ntional facilities, and supports observational programs associated with\nmeteorological research. The NSSL base facilities consist of two 10-cm\nmeteorological Doppler radars, a WSR-57 (surveillance radar), a tall (444 m)\ntower, a 52-station surface network, an air traffic control facility, and\nequipment for measuring electrical phenomena in the atmosphere. The group\nalso provides engineering support for the NEXRAD/JSPO Interim Operational Test\nFacility of NWS.\nAccomplishments FY 1984\nCOMPUTING AND DATA PROCESSING\nAn award was made to purchase a DEC VAX 11/780 computer system consisting\nof 12-megabyte memory, 1778-megabyte disk storage, and three magnetic tape\ndrives. This system will be used for interactive editing of Doppler radar\ndata, for editing and archiving of other NSSL-collected data, and as a remote\njob entry link to the CDC 750 in Boulder.\nNSSL's Perkin-Elmer 3242 was upgraded to 8 megabytes of memory; it con-\ntinues to drive a color graphics unit for the display of real-time radar\nproducts and is used for quality control of data from radars, lightning sen-\nsors, and weather sensors in the NSSL surface network and on the tall tower.\nUniversal format tapes were produced for Doppler radar data and distrib-\nuted to one university for evaluation. During the spring collection program,\n477 Doppler radar data tapes were recorded.\nNSSL supplied data sets to these users:\nAlberta Hail Project\n(G.S. Strong)\nCIMMS\n(G. Lesins)\nNASA\n(G. Heymsfield)\nNASA, Huntsville, Ala.\n(S. Goodman)\nNWS, Silver Spring, Md.\n(K. Shreeve)\nOklahoma University\n(H. Bluestein)\nParks College\n(R. Pasken)\nRice University\n(G. Byrne)\nSperry Corporation\n(W. Heiss)\nSystems and Applied Sciences\n(G. Smythe)\nTexas A&M\n(G. Sickler)\nTexas Tech University\n(K. Mehta)\nUniversity of Arizona\n(N. Feldman)\nUniversity of Quebec at Montreal\n(I. Zawadski)\nUniversity of Tennessee\n(M.A. Abidi)\nUniversity of Wisconsin\n(R. Ferrare, R.N. Mower)\n134","FACILITIES ENGINEERING\nDuring the first quarter of FY 1984 the CESD Group participated in a\nprogram with the Air Force for evaluation of the weather detection capability\nof an airborne radar. Weather radar data from the NSSL ground-based radars\nwere used as the benchmark for this comparison and evaluation.\nAs in the past, much of the group effort in both engineering and support\ncenters around the spring data acquisition program. During this year, all\nbase facilities, i.e., tall tower, a 28-station surface network, two Doppler\nradars, WSR-57 surveillance radar, and the air traffic control facility were\noperated from 1 April through 15 June in support of this program.\nData from the Doppler radar at Norman were routinely transferred to the\nWeather Service Forecast Office at Will Rogers Airport in quasi-real time\nduring the Spring Program. These data proved useful to the duty forecaster;\nthe records kept during the experiment are being studied in order to evaluate\nthis capability in relation to an effective evolution in data sources for the\nNational Weather Service.\nScreening of radar data has been greatly facilitated at NSSL through\nfrequent photography of the Norman Doppler data displays during data\nacquisition. The slides have been developed and cataloged, and have usually\nbeen available for viewing within 2 days after the event. The file is\nretained as a permanent part of the Laboratory data base.\nDesign, fabrication, and testing of both the coherent and incoherent\nradar ground clutter cancelers were completed. Data needed for a comprehen-\nsive performance evaluation have been acquired, and analysis will be completed\nduring FY 1985.\nDesign of dual polarization capability for the Doppler radar at Cimarron\nis continuing although receipt of the microwave hardware necessary to imple-\nment the capability has been delayed. The stringent design requirements for\nNSSL hardware, particularly the switchable ferrite circulators, have presented\na challenge to the manufacturer.\nPlans FY 1985\nNSSL\nCOMPUTING AND DATA PROCESSING\nThe new VAX 11/780 will be installed early in 1985 and additional support\nequipment will be added as follows: electrostatic plotter, 7-track\nmagnetic tape drive, and a two-monitor color graphics system. By\nmid-year, a Class VI supercomputer should be operational in Gaithersburg,\nMd. and a data communication link will be established between NSSL and\nthe Class VI. By the end of FY 1985, all major computing will be shifted\nto the Class VI machine.\n135","FACILITIES ENGINEERING\nThe NSSL radar system was configured for ground-based testing of an\nairborne radar manufactured by Sperry Corporation. The data acquisition\nprogram and evaluation by comparison with the NSSL ground-based radar\nwill be completed during the first quarter of FY 1985.\nThe NSSL radar facilities will be operated in support of data acquisition\nduring winter storms in the second quarter of FY 1985. This program is\nsupported by the National Science Foundation and administered by the\nUniversity of Oklahoma.\nAssuming delivery of critical microwave hardware, NSSL will establish a\nDoppler radar dual-polarization capability on the Cimarron radar system\nduring the second quarter of FY 1985. The dual-polarization radar meas-\nurement has potential for improving the radar rainfall estimates, iden-\ntifying hail, and studying physical processes attending electrification\nand hydrometeor deformation.\nDuring the third quarter of FY 1985, NSSL will host participants of the\nOklahoma-Kansas PRE-STORM Program, a prologue to the STORM-Central\nProgram in 1988. Major facility changes will involve deployment of\n42 surface weather stations throughout Oklahoma and expansion of the\ncloud-to-ground lightning location network to cover a large portion of\nthe southern Great Plains. Other research plans include a hail study\nprogram, dual-Doppler radar studies, storm electricity studies, and\npreliminary evaluation of dual-polarization Doppler radar potential.\nGeneral facilities expansion and modification plans include the commis-\nsioning of a second-generation data logger on the NSSL instrumented\ntower; design, fabrication, and installation of a radar signal prepro-\ncessor and an expanded real-time display terminal on the Cimarron radar;\nand the design and installation of a differential reflectivity calculator\nto operate in real time.\n136","C. Gordon Little\nWAVE PROPAGATIONLABORATORY\nDirector\nBoulder, Colorado\nDirector\nO/P\nDep. Director\nESG\nCooperative\nCRP\nWRP PROFS WMP\nInstitutes\nGFDL\nNSSL\nWPL\nARL\nAL\nSEL\nAOML\nPMEL\nGLERL\nNOAA's core mission of atmospheric and oceanic forecasts and warnings\nrequires that it observe the present states of the atmosphere and ocean in\norder to be able to predict their future states. Since both media are three-\ndimensional, the observations must also be three-dimensional; moreover, the\ndata sets must adequately resolve spatial or temporal structures at least as\nsmall as those to be forecast.\nIn general, the denser the observational data set in space and time, the\nmore complete and accurate the services can be. Experience has shown that in\nsitu measurement methods, which require a sensor at each measurement location,\nare too expensive to be practical for anything but the largest scale phenom-\nena. In 1967, the Wave Propagation Laboratory (WPL) was set up to explore\nthe possibility that remote sensors might provide the several-orders-of mag-\nnitude improvement in space/time density of observations required to predict\nor warn of smaller scale phenomena.\nThe WPL mission is, therefore, to improve the Nation's geophysical re-\nsearch and services, through the development and application of cost-\nWPL\neffective remote measurement systems. To achieve this goal, it must success-\nfully perform the following functions:\nTheoretical and experimental studies of the interactions of acoustic and\nelectromagnetic waves with the atmosphere or ocean, with particular\nreference to the use of such interactions for remote-sensing and tele-\ncommunication purposes.\nDevelopment and experimental evaluation of new geophysical remote-\nsensing concepts.\nApplication of the unique advantages of newly developed remote-sensing\ntechniques to atmospheric and oceanic research.\n137","Improvement of the Nation's monitoring, forecasting, warning, and\nresearch services, through transfer of remote-sensing technology to\nothers.\nBecause observational capability underlies essentially all geophysical\nresearch and services, WPL's research has broad impact. The following presen-\ntations give a brief rationale for the research programs, and summarize the\nFY-1984 programs and FY-1985 plans. Where appropriate, the research tasks\nwithin each program are grouped according to meteorological scale.\nWEATHER OBSERVATION AND PREDICTION\nWPL's contributions to weather observation and prediction support NOAA's\nlargest and most important single service, namely, weather forecasts and warn-\nings. Such services are required on many space and time scales. Thus,\nit\nis\nimportant to recognize that WPL's remote-sensing R&D program includes contri-\nbutions on all scales from the micrometeorological to the global.\nMICROMETEOROLOGICAL\nAND BOUNDARY LAYER R&D\nResearch on micrometeorological processes in the atmospheric boundary\nlayer is important because these processes include the turbulent fluxes of\nheat, moisture, and momentum that change the dynamic and thermodynamic proper-\nties of air masses. Remote sensors contribute uniquely to the research by\nproviding the resolution and continuity in both space and time that are\nrequired to observe, monitor, understand, and predict these important boundary\nlayer processes, WPL has long led in the development and application of such\nsensors.\nAccomplishments FY 1984\nSENSOR DEVELOPMENT\nAn 8.6-mm-wavelength scatterometer for observation of cloud and precipi-\ntation particles was fabricated and tested on warm (i.e., ice-free) clouds\nnear Hilo, Hawaii.\nAppropriate software was completed to permit the use of an array pro-\ncessor in the processing of FM/CW radar data.\nAn acoustic microsounder operating in the 6-7 kHz range was developed to\nmeasure atmospheric structure between 10 and 100 m above the ground. It was\ntested successfully during the DOE/EPA complex terrain field program in Brush\nCreek Canyon, With Doppler capability added, this device will greatly enhance\nWPL's capability for wind measurement over irregular terrain.\n138","WPL's 2-kHz bistatic Doppler sodar was modified to operate in a two-axis\nmonostatic mode. Two such systems were deployed in support of EPA's Tracy\npowerplant experiment and the Brush Creek experiment.\nWPL evaluated the performance of four commercially available Doppler\nsodars. This study was conducted for EPA to determine the capabilities of\nacoustic Doppler sounding in environmental monitoring programs.\nThe second, third, and fourth phases of the Flatville experiment spon-\nsored by the Army Research office, were completed. Amplitude, phase dif-\nference, and angular fluctuation data were taken at a range of frequencies\nfrom 140 GHz to 180 GHz in clear air, rain, fog, and snow. The measurements\nare in the process of being compared with the data from our extensive meteoro-\nlogical instrumentation consisting of high-speed humidity, temperature, and\nwind fluctuation sensors; one- and two-dimensional aerosol probes, and an\narray of path-averaging sensors that measure wind, rain, and refractive tur-\nbulence.\nWPL has developed a technique for inferring the path-averaged momentum\nflux from turbulence microscale measurements on paths of up to 250 m.\nProgress was made during the fiscal year on measuring the intensity variance\n(scintillation) at both 10.6-pm and millimeter wavelengths. These three\nmeasurements, combined with scintillation data at an appropriate mid-infrared\nfrequency, will give us sensitivity to turbulent water vapor, temperature, and\nwind speed fluctuations, and ultimately the ability to measure the path-\naveraged fluxes of these quantities.\nLine-of-sight optical devices have demonstrated the ability to measure\npath-averaged values of boundary layer parameters such as wind speed. WPL has\ndesigned and built an optical wind and refractive turbulence profiler that\nwill produce high resolution profiles of wind and refractive turbulence on\nboth horizontal and slant paths of several kilometers.\nIn the process of developing a rain and drop-size distribution gauge that\ngives path-averaged values over hydrologically important distances (several\nkilometers), WPL has taken the first measurements of the effects of rain on\nphase difference spectra. Previous sensors, whose measurements are based on\namplitude fluctuation, have had limited paths because of the onset of multiple\nscattering in heavy rain. Techniques based on phase difference are insen-\nsitive to multiple scattering and appear to work on much longer paths.\nWPL\nRESEARCH\nA gravity/shear wave experiment was conducted in May 1984 in which all\nwave events detected during the 1-month period by the newly expanded micro-\nbarograph array at ERL's Boulder Atmospheric Observatory (BAO) were recorded,\nprocessed, and displayed, New techniques were developed to display wave and\nturbulence parameters in graphical form. Scientists at WPL and Georgia\nInstitute of Technology are analyzing the data.\nThe laboratory also participated in Project Phoenix II, a major convec-\ntive boundary layer study performed in cooperation with the National Center\n139","for Atmospheric Research (NCAR) and the University of Oklahoma. WPL's contri-\nbution included boundary layer measurements from dual-Doppler radars, sensors\non the BAO 300-m tower, and rawinsonde flights.\nIn conjunction with Phoenix-II, WPL conducted a microburst experiment at\nthe BAO, integrating data sets from the tower, the optical triangle\nconvergence-measuring system, radars, lidar, and aircraft. Their different\nsignatures provide the basis for a better definition of microbursts and their\nstructure.\nA stable-layer experiment, designed to study the structure of very thin\nshear layers, yielded more examples of the intense layering observed in an\nearlier experiment, Their implications to radar transmission in the boundary\nlayer are being examined.\nA report was made to EPA on the development of a technique for indirectly\nestimating boundary layer parameters for dispersion modeling.\nAnalysis of wind shear events during the 1983 Joint Airport Weather\nStudies (JAWS) experiment was completed.\nSeveral Front Range meteorological events were analyzed in detail, in a\nreport on Project Aeolus.\nA multiwavelength, multipolarization study of chaff in the boundary\nlayer was performed in conjunction with NCAR's dual-polarization radar.\nPolarization signatures expected of prolate ice crystals in cirrus clouds\nhave been computed for radar wavelengths of 8.6 mm and 3 cm.\nAn experiment was performed in conjunction with Aeromet, Inc. to study\nproperties of stratiform clouds on the slopes of Mauna Loa in Hawaii. This\nwas in preparation for a more extensive study, using the 8.6-mm-wavelength\nradar and the 20-30 GHz radiometer, that will be performed, funds permitting,\nduring the summer of 1985.\nPlans FY 1985\nSENSOR DEVELOPMENT\nWPL will participate in one more Flatville field program in FY 1985. We\nwill also analyze existing data tapes to determine atmospheric propagation\neffects on millimeter waves and relate these effects to the state of the\natmosphere as indicated by our extensive meteorological data set.\nIn connection with the flux measurement program, WPL will continue to\ninvestigate the turbulence spectrum in the region near the inner scale, ana-\nlyze the Flatville millimeter-wave scintillation data for sensitivity to\nhumidity fluctuations, and search for an optimal, mid-infrared frequency\nsuitable to complete the three-frequency flux measurement technique.\n140","WPL will work with the U.S. Geological Survey (USGS) and the National\nOcean Service (NOS) to analyze different active optical techniques for\nobtaining higher precision in geodetic leveling.\nSlant path measurements of turbulence parameters and wind have not\nprogressed rapidly because of the difficulty of folding the optical path to\nobtain the necessary single-ended operation. Working with the Air Force,\nWPL will build and test an optical instrument that will work on a slant path,\nusing a tower-mounted retroreflector.\nThe polarization properties of microwave-reflecting chaff at wavelengths\nranging from 8.6 mm to 10 cm will be investigated to assess the suitability of\nchaff as a depolarizing target in precipitation.\nDoppler wind-sensing capability will be added to the microsodar, there-\nby providing WPL with a truly mobile wind-sensing capability between 10 and\n100 m.\nRESEARCH\nThe infrared Doppler lidar, and the multiwavelength lidar (operating at\nvisible and ultraviolet wavelengths) will be used to measure backscatter from\nlenticular wave clouds. By inverting the three-wavelength measurements, the\ncloud particle size distribution will be obtained, allowing the study of\nparticle growth in such simple, laminar clouds.\nThe lidars will also routinely monitor upper troposphere and stratosphere\nturbidity in support of GMCC and NESDIS ozone measurements.\nAnalysis of the data from Project Phoenix-II will continue with emphasis\non elucidating the fine-scale structure of the boundary layer.\nA study of the statistics of gust fronts and microbursts measured during\nthe JAWS project will be completed, for application to improving aviation\nsafety.\nAnalyses of orographic flows, which can affect aircraft response at com-\nmercial flight altitudes, will be carried out.\nAn experiment will be conducted at the BAO to study atmospheric processes\non the meso-gamma - scale, using WPL in situ and remote sensors. The experiment\nWPL\nwill focus on events relevant to airport meteorology and air quality.\nDevelopment of a Front Range boundary layer model that replicates the\nDenver vortex will be completed; data from the Phoenix-II experiment will be\nused for model validation.\nR&D ON MESO-BETA AND GAMMA SCALES\nA single ground-based radar or lidar system can remotely monitor atmo-\nspheric processes on the meso-gamma (2 to 20 km) and perhaps the meso-beta (20\n141","to 200 km) scales. Such data sets are required for an extraordinarily wide\nrange of atmospheric research problems, as well as for short-term local\nweather nowcasts and forecasts. WPL progress in this area assigned to the\nWeather Observing and Prediction program is divided into two main categories,\nmesoscale sensor development and mesoscale research. (Specific applications\nof WPL's mesoscale remote sensors to air pollution studies are discussed in\nthe section on Air Quality.)\nAccomplishments FY 1984\nMESOSCALE SENSOR DEVELOPMENT\nThe pulsed, infrared, Doppler lidar was improved through implementation\nof computer-controlled azimuth and elevation scanning. This allows pre-\nprogrammed scan patterns to be developed for measuring winds in canyons or\nalong aircraft glide slopes without wasted time for turnarounds or scanning\nirrelevant regions. The spectral moment processor was calibrated at the BAO\ntower.\nA new pulsed, coherent, CO2 laser has been developed for WPL through a\ncontract let to the private sector. This laser will provide an increase in\naverage infrared output energy by a factor of 100 over the present unit. It\npassed its acceptance tests in September 1984, and it will be shipped to\nBoulder in October.\nSide-by-side operation of the 915-MHz Profiler and the Doppler lidar at\nStapleton Airport provided an independent check on Profiler wind measurement\naccuracy. The two remote sensors usually agreed closely, within 1 m S\nDynamic or changing meteorological conditions resulted in less close\nagreement; the reasons for these differences are under investigation.\nTwo-dimensional (horizontal and vertical) maps of liquid water and water\nvapor in cloud were developed using the technique of radiometric tomography,\nin which the data from two spaced radiometers are combined.\nThe steerable-beam 20-30 GHz radiometer has been implemented to provide\ncontinuous real-time profiles of water vapor.\nA new technique for measuring entrainment in clouds, utilizing depolari-\nzation of circularly polarized radar waves by chaff, has been evaluated and\nhas undergone preliminary tests.\nThe 3-cm radars have new microwave circuitry that has decreased undesired\nleakage so that estimates of Doppler spectral widths are more reliable.\nSecond-moment turbulent quantities have been computed from fluctuations\nof the Doppler velocity obtained by radar. The method has potential applica-\ntion in the formation and dissipation of stratus clouds.\nCoefficients for statistical retrieval of total precipitable water from\ndual-channel radiometer data are normally derived from long-term radiosonde\n142","data; it has been found that they can be estimated, as a function of climatic\nmean surface pressure, for locations where radiosonde data are not available.\nMESO-BETA AND -GAMMA SCALE RESEARCH\nMeasurements with the NOAA P-3 research aircraft during Arctic Cyclone\nExperiment, 1984 (ACE, 1984) described the structure of previously unexplored\narctic atmospheric phenomena. Highlights of this experiment were the documen-\ntation of (1) the Spitzbergen coastal ice edge atmospheric frontal zone, (2)\nwarm frontal structure over the polar ice cap, (3) the three-dimensional\nstructure of a polar low, (4) a frontal occlusion south of Iceland, and (5) a\nNorwegian Sea convergence line.\nMeasurements from the BAO tower, acoustic echosounder, and research\naircraft documented the density current hydraulic head structure at the\nleading edge of surface cold fronts. The analysis constitutes a description\nof the role of ~1-km-scale frontal heads in triggering intense squall-line\nmesoconvection.\nResults from the Arctic gas and aerosol sampling program (AGASP) 1983\nprovide the first direct documentation of stratospheric-tropospheric exchange\nin arctic latitudes. Measurements documented the injection of stratospheric\nozone and El Chichon volcanic debris into the Arctic troposphere during tropo-\npause folding events.\nWPL continued numerical studies that simulate the combining of high ver-\ntical resolution and temporally continuous radar wind profiles with low-\nvertical-resolution but temporally continuous ground-based and satellite\nradiometric temperature profiles. The results, published in collaboration\nwith researchers from the University of Miami, demonstrate the value of wind\nprofiler soundings in enhancing the vertical structure of radiometrically\nderived thermal retrievals.\nThe Doppler lidar was operated near the BAO tower in July, and succeeded\nin measuring several downburst wind events, including one detected before it\nreached the ground. Subsequent gust arc dynamics were also recorded and\nobserved in real time on the Doppler processor color display. These events\nare now being analyzed in an attempt to explain the dynamics of such short-\nlived wind shears.\nWPL\nDuring DOE's Atmospheric Studies in Complex Terrain (ASCOT) 1984, the\nDoppler lidar measured wind cross sections in Brush Creek Canyon near\nDe Beque, Colo. The development of down-valley winds, side canyon drainage,\nand subsequent up-valley flow after mid-morning were observed and recorded for\nlater evaluation. The lidar trailer with its real-time wind display in color\nwas chosen as experiment command post by the project field manager.\nThe FAA was informed on the performance of its wind shear alert system\nduring the JAWS project. The results are being used as a basis for making\nimprovements in the FAA wind shear alert systems.\n143","WPL participated in an FAA-sponsored experiment to determine the feasibi-\nlity of reducing the vertical separation of commercial jet aircraft operating\nin orographic flows. Orographically induced altitude variations at commercial\nflight altitudes were discovered to be larger than FAA had realized.\nThe two 3.2-cm-wavelength radars participated in a storm electrification\nexperiment at the Langmuir Laboratory near Socorro, N. Mex., in conjunction\nwith investigators from NSSL, New Mexico Institute of Mining and Technology,\nand NCAR.\nJoint measurements by millimeter-wave radiometer and radar have iden-\ntified the amount and location of supercooled liquid in a winter snowstorm.\nWPL participated in atmospheric radar projects relevant to national\nsecurity at Kwajalein Atoll.\nPlans FY 1985\nMESOSCALE SENSOR DEVELOPMENT\nThe new coherent infrared laser, providing 2 joules per pulse at a 50-Hz\nrepetition rate, will be tested in the laboratory, then integrated into the\npresent lidar.\nA Data General S-120 computer has been procured and will be installed in\nthe 8.6-mm-wavelength radar. This will allow the implementation of software\nfor real-time data display.\nInvestigation will be started into the possibility of reconfiguring the\nantennas of both the 8.6-mm and 3.2-cm wavelength radars to allow greater\npolarization sensitivity.\nMESO-BETA AND -GAMMA SCALE RESEARCH\nThe analysis and publication of observations from the Arctic Cyclone\nExperiment, 1984, a collaborative effort between NOAA, the Navy, NASA, CIRES,\nand the Norwegian Meteorological Service will be continued.\nJet streams, fronts, extratropical cyclones, and mesoconvective weather\nwill be studied, using the WPL \"Colorado Triangle\" radar wind profiler and\nradiometric water vapor mesoscale network.\nField experiments with profilers, weather radars, radiometers, and lidars\nwill be conducted, to demonstrate the application of WPL remote-sensing\ninstrumentation to the observation, diagnostics, and forecasting of mesoscale\nweather systems.\nA study of entrainment and mass flow through tropical cumulus clouds will\nbe undertaken using the 8.6-mm-wavelength radar and chaff. This will take\n144","place, funds permitting, in cooperation with the University of Washington, the\nIllinois State Water Survey, University of Illinois, and NCAR on the island of\nHawaii.\nA data set on warm clouds using 8.6-mm-wavelength radar, scatterometer,\nand dual-channel radiometer, with in situ sensors will be obtained, funds per-\nmitting.\nJoint measurements on the properties of clouds using dual-polarization\nDoppler radars and a steerable dual-channel radiometer will be expanded.\nThe spatial distribution of tropospheric water vapor and its continuum\nabsorption at low surface pressure will be measured using dual channel\nradiometry.\nRadiometer measurements of path-integrated liquid and vapor in support of\ngeodetic metrology will be continued.\nThe 3.2-cm-wavelength radars will continue to participate in studies of\ncloud and storm structure.\nR&D ON SYNOPTIC AND MESO-ALPHA SCALES\nAlthough individual ground-based remote sensors are limited by Earth cur-\nvature to meso-beta scale applications, arrays of such sensors can be used to\nstudy atmospheric processes up to continental scale. WPL's planned contribu-\ntion to this scale is the Profiler, a combined radar-radiometric system for\nthe continuous measurement of profiles of wind, temperature, and humidity.\nA\nsuitable array of such systems could continuously provide the three-\ndimensional fields of these parameters on the meso-alpha (200 to 2,000 km) and\nsynoptic (2,000 to 10,000 km) scales for numerical weather prediction (NWP)\nSuch a system would have major impact on NWP since the observation data could\nbe (1) time-averaged to remove aliasing of high-frequency components, (2)\nentered more frequently into the NWP algorithms, and (3) inserted in the form\nof time derivatives as well as time averages. It is also believed that the\nwind field data (which are critical to mesoscale NWP) would be considerably\nmore accurate and representative than those available from radiosondes.\nWPL\nAccomplishments FY 1984\nThe 405-MHz wind profiler was built and is now undergoing engineering\ntests. This first version will be used to confirm the scattering properties\nof the atmosphere at this frequency.\nThe Colorado wind profiler network was operated in support of further\ntests, and applications that included use of the data by the FAA to study\naircraft separation standards over mountains, and air traffic control proce-\ndures in the Denver area. The data were also used to study preconvective\nstorm convergence and vorticity patterns, and as part of the data base for a\nPROFS FY-1984 exercise. An inexpensive personal-computer-based profiler\n145","display was developed and is being used at the Denver National Weather Service\n(NWS) forecast office and by meteorologists in the NESDIS Regional and\nMesoscale Meteorology (RAMM) group at Colorado State University.\nOperation of the six-channel microwave radiometer was continued and the\ndata used in a study of the remote detection of hazardous aircraft icing con-\nditions and in a cloud detection experiment. Concepts for introducing higher\nvertical resolution into the thermodynamic profilers were developed, including\nan improved method for the automatic detection and measurement of the height\nof the tropopause. These concepts use wind profile information to derive the\ntemperature field, which is then used to introduce baroclinic zones and tem-\nperature inversions into the passive radiometer-derived profiles.\nGround-based temperature profiles have been combined successfully with\ntemperature profiles from the orbiting NOAA satellites. Similar combinations\nhave been simulated with sounding data from geostationary satellites.\nSoftware for combining the ground-based and satellite data in real time has\nbeen prepared.\nBrightness temperatures affected by the microwave transmission charac-\nteristics of reflectors wetted by rain have been calculated and computed for\nmillimeter-wa radiometers.\nComparisons of backscattered intensities from the zenith for the 10-cm-\nwavelength FM/CW radar and the 33 cm-wavelength Stapleton profiler were made.\nThese indicated that the inner scale of turbulence increases rapidly to more\nthan 5 cm above the top of the boundary layer, indicating that 10 cm is not a\nsuitable wavelength for wind profiling above the boundary layer.\nPlans FY 1985\nA special task team will be formed to design and implement a Profiler\nnetwork to support the National Stormscale Operational and Research\nMeteorology (STORM) program and Profiler operational evaluation by NWS. This\nnetwork will contain 30 wind profilers and a hub for data collection and net-\nwork control. In FY 1985 this project will concentrate on the creation of a\nwind-profiling design that can be transferred to industry for mass production\nand wide availability to multiple users.\nResearch on the development of instruments and/or techniques that are\ncapable of producing high-resolution temperature/moisture profiles will be\naccelerated. This effort will examine the feasibility of various sensor com-\nbinations and the application of the principles of atmospheric dynamics to\nachieve the desired height resolution.\nA triangular array of three wind/humidity profilers will be operated on\nthe high plains of eastern Colorado, to study the ability of such an array to\nmonitor moisture convergence, and hence to contribute to cloud and precipita-\ntion forecasting.\n146","R&D ON THE GLOBAL SCALE\nWINDSAT (wind-measuring satellite system) is a concept for measuring the\nglobal wind field at multiple levels in the atmosphere, twice each day, by\nmeans of a pulsed, infrared, Doppler lidar on a polar-orbiting satellite. WPL\nhas worked on the WINDSAT project for several years. Because of funding\nrestrictions, and in the absence of a clear requirement for continuing analy-\nsis of WINDSAT from NESDIS or NWS, the project was terminated during FY 1984.\nWe will continue to develop Doppler lidar technology with our trailer-based\nsystem, and be ready to assist in any reopening of the WINDSAT concept in the\nfuture.\nAIR QUALITY\nNOAA's weather service mission includes the provision of meteorological\ninformation and understanding relevant to air quality. WPL contributes to\nthis program through the application of its remote sensors to the measurement\nthe three-dimensional fields of wind, turbulence, and aerosol in experi-\nof\nments relating to air pollution.\nAccomplishments FY 1984\nA report was provided to the Department of Energy on the use of acoustic\necho sounders for the study of flows in complex terrain.\nData were analyzed and reported to EPA sponsors from the Small Hill\nImpaction experiment conducted near Farmington, N. Mex., and from the CONDORS\n(Convective Dispersion Observed by Remote Sensors) experiment at the BAO tower\nduring FY 1983. The data were obtained with the multiwavelength lidar,\nacoustic sounders, tethersondes, sonic anemometers, and optical transverse\nwind sensors. EPA is using the data to validate plume dispersion models.\nThe same set of experiment equipment participated in a 3-week experiment\nat the Tracy powerplant near Sparks, Nev., in September 1984. Transport of\nthe seeded plume was observed with the lidar to ranges in excess of 5 km.\nThe ASCOT field program is currently using the WPL-designed transverse\nWPL\noptical wind sensor as the instrument of choice to measure flows in complex\nterrain. Twelve optical paths were set up and used during the FY-1984 ASCOT\nexperiment.\nRadar data from project CONDORS 83, a plume transport and diffusion\nexperiment performed in cooperation with EPA, have been analyzed for the\nsix\nhighest priority cases. In this experiment, oil fog and aluminized chaff were\nreleased at different heights from the BAO tower, and tracked by WPL's lidar\nand radar systems.\nThe 8.6-mm-wavelength radar measured wind flow associated with a large\nexplosion as a part of the Defense Nuclear Agency's Direct Course experiment.\n147","For EPA, we evaluated the performance of various in situ sensors routi-\nnely used for turbulence measurements in environmental monitoring applica-\ntions.\nPlans FY 1985\nAnalysis of radar data from project CONDORS 83 will continue. The data\nwill be combined with lidar and in situ data from BAO tower sensors for use by\nEPA researchers,\nAnalysis of data from the September 1984 Nevada plume experiment at the\nTracy powerplant will be completed.\nLarge eddy structure analysis of data collected during the 1982 EPA Small\nHill Plume Impaction experiment in Farmington, N. Mex., was completed.\nCLIMATE\nThe United States has a major program to understand the processes that\ndetermine climate. Fundamental to the studies is the role of the ocean, which\nacts like a flywheel, storing and releasing vast quantities of heat. WPL is\ndeveloping and applying remote sensors to ocean climate studies.\nAccomplishments FY 1984\nCODAR (Coastal Ocean Dynamics Applications Radar) was operated for 2\nmonths on the east coast of Florida to map surface currents during the\nDecember 1983 STACS (SubTropical Atlantic Climate Studies) program. The two\nsystems provided surface-current maps showing the spatial structure and tem-\nporal variability of the Florida current, which carries almost all the north-\nward oceanic heat flow in the North Atlantic.\nPlans FY 1985\nAnalysis of the STACS data sets will continue, to determine the adequacy\nof CODAR to measure total transport and to study the dynamics of surface\nsignatures of subsurface features.\nMARINE OBSERVATION AND PREDICTION\nThe difficulty and expense of obtaining in situ observations of ocean\nparameters make remote-sensing methods highly desirable. WPL is therefore\nactive in the development, testing, and use of remote sensors for ocean param-\neters.\n148","Accomplishments FY 1984\nIn January and February 1984, WPL led a multi-agency, multination Arctic\nCyclone Experiment, using the NOAA P-3 research aircraft to (1) develop and\nevaluate remote-sensing techniques for monitoring sea state and ice; (2) study\nthe meteorology of the Arctic, with emphasis on the Icelandic low and polar\nlows; and (3) measure CO2 exchanges between the air and sea in the polar\noceans. NASA, the U.S. Navy, and Norwegian and Icelandic agencies par-\nticipated in the experiment. The NASA P-3 research aircraft participated in\nthe Iceland phase with a full complement of remote-sensing instruments. More\nthan 100 hours of research flight time provided great quantities of data over\nthe Greenland Ice Cap, the ocean front north of Iceland and the ice zone in\nthe Denmark Strait, the area around Spitzbergen, and off the west coast of\nNorway. Observations of a mature polar low were obtained on 27 February 1984.\nA new microwave radiometer built by the University of Massachusetts was\nflown for the first time onboard the NASA aircraft during the Arctic Cyclone\nExperiment. (It was later installed onboard the NOAA P-3 aircraft and suc-\ncessfully obtained data during the summer 1984 Marginal Ice Zone Experiment--\nMIZEX. This instrument also participated in research flights of Hurricane\nNorbert in the eastern Pacific.) Commonly known as the Stepped Frequency\nMicrowave Radiometer (SFMR), the University of Massachusetts instrument\nprovides information on the type and concentration of sea ice, ocean surface\nwind speeds, rain rate, and the microwave emission properties of snow and ice.\nA new method for processing CODAR echoes retains the objectivity of\nleast-squares techniques, while maintaining the speed of earlier linearized\nmethods.\nTwo CODAR vans were prepared, and one was used during the winter\n1983-1984 STACS program in Florida. These vans will make future CODAR field\noperations much more economical. In addition, the real-time display and the\ndetailed documentation on CODAR have been completed.\nResults of the CODAR work in the Alboran Sea have shown wide variability\nof the surface current jet in the Strait of Gibraltar.\nPlans FY 1985\nWPL\nAvailable to WPL from the University of Massachusetts is a new radar\nscatterometer to measure surface wind velocity fields and to participate in\nexperiments to study surface scattering characteristics. This instrument\noperates in the same frequency band as the European ERS-1 satellite-borne\nscatterometer. If funds become available, this instrument will be made flight\nready and installed onboard the NOAA P-3. It would then be ready to par-\nticipate in a PMEL experiment and/or the NASA Rain-Ocean Measurement experi-\nment in the spring of 1985. The latter experiment is important for the\nunderstanding of the effects of precipitation on ocean surface scattering and\nthe attenuation of microwave signals through the precipitation. Future\nsatellite-borne instruments will need this information for the proper\ninterpretation of scatterometer and altimeter data obtained over severe\nstorms.\n149","WPL and AOML plan (subject to funding availability) to set up the two\nCODAR systems at Fisher Island and Ft. Lauderdale and run them for about 1\nyear. The surface current measurements will be used in assisting search and\nrescue efforts by the Coast Guard, and in oceanographic research by NOAA.\n150","Lester Machta\nAIR RESOURCESLABORATORY\nDirector\nRockville, Maryland\nDirector\nO/P\nDep. Director\nCooperative\nESG\nInstitutes\nCRP WRP PROFS WMP\nAL\nSEL\nAOML\nPMEL\nGLERL\nGFDL\nNSSL\nWPL\nARL\nThe Air Resources Laboratory (ARL) includes a headquarters group in\nRockville, Md. the Field Research Division in Idaho Falls, Idaho; the\nAtmospheric Turbulence and Diffusion Division (ATDD) in Oak Ridge, Tenn.; the\nMeteorology Division in Research Triangle Park, N.C.; the Solar Radiation\nFacility, the Sun-Climate Staff, the Air Quality Division, and the Geophysical\nMonitoring for Climatic Change Division (GMCC) in Boulder, Colo. ; and GMCC\nobservatories at Mauna Loa (Hawaii), Barrow (Alaska), the South Pole, and\nAmerican Samoa.\nARL research is geared to needs of users, who are frequently other Federal\nagencies with related missions. Funding and guidance derive from this asso-\nciation through interagency agreements. In some cases, the ARL unit under\ncontract to another agency acts as its meteorological arm, to provide meteoro-\nlogical guidance. Most ARL research deals with the use of meteorology to\nunderstand and predict human influence on the environment, especially with\nregard to the atmospheric transport and diffusion of toxic effluents. General\nareas of study include turbulence and diffusion in the atmosphere, atmospheric\ntrajectories from microscales to global scales, meteorology of air pollution,\nCO2 and climate, acid rain, and monitoring of atmospheric constituents for\nARL\nclimatic change. Following general descriptions of the work of the various\nARL groups, ARL research activities are described here under two main\nheadings, Air Quality and Climate.\nHEADQUARTERS GROUP\nThe ARL headquarters research group in Rockville develops models that\nsimulate local, regional, and global transport and diffusion of pollutants\ninjected into the atmosphere. Mesoscale and regional-scale versions of these\nmodels are being used extensively by the Department of Energy (DOE) to\nevaluate the environmental effects of various means of energy production.\n151","Air-sampling programs and other field experiments are conducted to provide\ndata for model verification. Major funding for this work is provided by the\nDOE Office of Health and Environmental Research and the Environmental\nProtection Agency (EPA) Research on total-ozone and ozone-profile data and\non the sources, transport, and deposition of acid precipitation is also being\ncarried out. In addition to these air quality studies, climate studies\ninclude research on the sources and sinks of CO2 in the atmosphere, on global\ntemperature and humidity changes, and on sunshine duration and cloudiness over\nthe contiguous United States.\nFIELD RESEARCH DIVISION\nMost of the research of ARL's Field Research Division in Idaho is sponsored\nby the Nuclear Regulatory Commission (NRC), DOE, and EPA. It is directed toward\ncurrent and anticipated environmental problems associated with the release to\nthe atmosphere of toxic and undesirable effluents by our industrialized society.\nThese problems include the quantification of downwind atmospheric dispersion\ncontributed by the meander of plumes under light wind and inversion conditions,\nthe effect of the land-sea interface, the effect of surface roughness and\ncomplex mountainous terrain, the measurement of the vertical as well as the\nhorizontal profile of plume concentration, and the measurement of air trajec-\ntories. Tracer gas techniques and radar-tracked, constant-level balloon trajec-\ntories as well as standard meteorological profiles of wind and temperature are\nused in full-scale field experiments to address these problems and provide the\nnecessary data for transport and diffusion model verification.\nATMOSPHERIC TURBULENCE & DIFFUSION DIVISION\nThe Atmospheric Turbulence and Diffusion Division in Oak Ridge, Tenn., is\ngenerally concerned with air quality and consists of research on the physics of\nthe lower atmosphere, with emphasis on the processes contributing to atmospheric\ntransport, dispersion, and deposition, and on the development of numerical\nmodels using the results of this research. The Division works closely with the\nOak Ridge National Laboratory and with atmospheric science units at other\nnational laboratories, universities, and Federal agencies. The largest single\nfunding source is the DOE Pollutant Characterization and Safety Research\nDivision. Additional sources include NOAA, EPA, the Department of Defense,\nand the U.S. Geological Survey (USGS). The program is organized in four major\nareas: plume transport and diffusion in the planetary boundary layer, complex\ntopography, atmosphere-canopy interactions, and dry deposition.\nMETEOROLOGY DIVISION\nMeteorology Division support and services to EPA include theoretical and\nexperimental studies of the physical processes affecting transport, diffusion,\ntransformation, and deposition of air pollutants; development, evaluation,\nmodification, and dissemination of air quality simulation models for inert and\nreactive pollutants' effects on weather and climate; and studies to define the\nrelationships between air quality and meteorological parameters.\nThe Meteorology Division provides operational support to various EPA\ngroups in their abatement and compliance activities. This includes technical\n152","advice; applications of air quality simulation models; evaluation of the\nmeteorological portions of state implementation plans, environmental impact\nstatements, and requests for variances; expert testimony at public hearings\nand judicial proceedings; emergency field services; and preparation of\ntechnical staff reports and documents.\nSUN-CLIMATE STAFF\nThe Sun-Climate Staff conducts fundamental research on the causes and\nmechanisms of climatic change, on time scales of months to decades, including\nsolar variability as a possible cause. The application is directed toward,\nbut not limited to, climatic change in the United States. The general\napproach is to develop understanding of climatic processes through analytical\nstudies using climatic, oceanographic, solar radiation, ozone, and other data,\nprincipally those representative of the current century. Fundamental research\non solar ultraviolet (UV) radiation is done through analysis and modeling of\nits secular variation and intensity and through direct measurement of UV flux.\nProgress is monitored on a grant to the University of Arizona that began in\nFY 1980. The grant's purposes are (1) to develop and deploy a highly accurate\nspectrometer and associated calibration device for ground-based measurement of\nthe secular characteristics of solar spectral changes in the UV, visible, and\nnear-infrared portions of the electromagnetic spectrum; and (2) to study the\neffects on surface-based measurements of atmospheric attenuation in these\nregions of the electromagnetic spectrum.\nAIR QUALITY DIVISION\nAir Quality Division research is directed, within the mesoscale in the\nlower troposphere, to (1) improving the understanding of the mechanisms of\nformation, residence times, and sinks of natural and anthropogenic cloud and ice\nnuclei; (2) elucidating the effects of those nuclei, other aerosols, and trace\ngases on the formation, colloidal stability, optical properties, and chemical\ncomposition of clouds; (3) determining the effects of pollutants on the\nradiation budget, visibility, and atmospheric electrical phenomena.\nSOLAR RADIATION FACILITY\nThe Solar Radiation Facility has the following functions: to maintain\nstandard instruments for solar radiation measurements, to calibrate pyranometers\nARL\nand pyrheliometers, to test specimen solar radiation instruments, and to make\nradiation measurements and establish their interrelationships. The Facility\nalso serves as a World Meteorological Organization (WMO) regional radiation\ncenter.\nGEOPHYSICAL MONITORING FOR CLIMATIC CHANGE DIVISION\nMeasurements of atmospheric trace gases and aerosols are made at NOAA's\nfour GMCC baseline observatories. These measurements are made to detect and\ndocument long-term global trends of trace constituents in the atmosphere.\n153","Assessments determine what sources and sinks control the long-term trend of a\ntrace constituent and what climatic impact can be expected from such a trend.\nAIR QUALITY\nATMOSPHERIC TRANSPORT\nAccomplishments FY 1984\nA major atmospheric transport and dispersion study, the Cross-Appalachian\nTracer Experiment (CAPTEX) was completed successfully in October 1983. The\nDOE, EPA, Electric Power Research Institute, National Weather Service (NWS),\nAtmospheric Environment Service of Canada and Ministries of the Environment of\nOntario and Quebec all participated in CAPTEX '83 under the direction of\nNOAA/ARL. There were five releases of a perfluorocarbon tracer gas at Dayton,\nOhio, and two releases at Sudbury, Ontario. Tracer concentrations were\nmeasured in air samples collected at 80 sites in the United States and Canada\nas far as 1,100 km away. The release locations were chosen, in\npart, because the Ohio Valley and the Sudbury area are considered to be signif-\nicant pollutant sources affecting air quality and contributing to acid rain in\nthe New England states and southeastern Canada. Seven sampling aircraft were\nused to determine the vertical distribution of the tracer. Both the density\nand frequency of upper-air soundings were doubled over the experimental area.\nThe thousands of CAPTEX air samples have been analyzed, and data are\nbeing compiled on magnetic tape along with extensive meteorological\nmeasurements. The data clearly show the path and dispersion of the tracer gas\nas it passes through the sampling array. CAPTEX will provide a unique data\nbase to evaluate and improve the transport and dispersion modules of\nlong-range pollution models.\nARL's year-long Metropolitan Tracer Experiment (METREX) in the\nWashington, D.C., area began in November 1983. The experiment is designed to\nprovide data to evaluate dispersion models in an urban setting and to develop\nand compare dispersion climatologies over adjacent urban and rural areas.\nPerfluorocarbon tracers are being released at two different sites every 36\nhours. Average monthly tracer concentrations are measured at about 90 sites,\nand continuous 8-h samples are being collected at three sites to provide more\ndetailed data on individual plumes. A third perfluorocarbon tracer, PMCP, has\nbeen developed for atmospheric dispersion studies and is being tested in\nMETREX.\nPlans FY 1985\nCAPTEX data processing will be completed early in FY 1985, and the data\nwill be made available to the atmospheric science community. A CAPTEX model\nevaluation workshop planned for mid-1985 will provide an opportunity to present\n154","and evaluate model results, suggest means of improving model performance, and\ndiscuss the lessons to be learned from CAPTEX for planning future large-scale\natmospheric transport and dispersion experiments.\nThe year-long METREX experiment will be completed in December 1984, and\nresults will be used to improve modeling of urban-rural effects on atmospheric\ndispersion.\nARL will participate in the DOE Atmospheric Studies in Complex Terrain\n(ASCOT) dispersion experiments in September-October 1984 in Colorado. All three\nperfluorocarbon tracers will play a key role in delineating nocturnal valley\nflows and early morning venting of pollutants out of Brush Creek Valley, located\nin an oil shale development area.\nATMOSPHERIC TRACERS\nAccomplishments FY 1984\nA preliminary elevated plume study was conducted near Reno, Nev., in\nNovember 1983. A 4-week full-scale elevated plume study was carried out near\nReno in August 1984. Measurement techniques were similar to those utilized\nfor the Hogback Ridge field experiment. EPA sponsored this research as a part\nof its Complex Terrain Model Development program.\nThe data measurements from the Shoreline Environmental Atmospheric\nDiffusion Experiment-1 (SEADEX-1) field program (conducted along the western\nshoreline of Lake Michigan) have been processed, summarized, and made ready\nfor reporting. NRC sponsored the analyses and report preparations as a part\nof its Shoreline Atmospheric Environment research program.\nAnalysis and reporting of the meteorological and tracer data for the\nConvective Diffusion Study was completed. The field study was sponsored by EPA.\nGaseous tracer release and sampling support was provided during the ASCOT\nfield measurements in the latter half of September 1984, in complex terrain near\nRifle, Colo.\nThe climatological description and data for the Idaho National Engineering\nLaboratory were upgraded. The revisions were made to include additional infor-\nmation and to include continuations of data collections performed since 1966.\nARL\nThe revision consists of two two-part volumes to support the engineering analy-\nsis of local and regional meteorology, climatology, and dispersion climatology.\nCondensed short contributions were prepared from these revisions for inclusion\nin the multivolume Idaho National Engineering Laboratory Environmental\nCharacterization Report.\nPlans FY 1985\nThe meteorological and tracer measurements performed during August 1984,\nusing tracer emissions from a powerplant stack near Reno will be tabulated,\n155","analyzed, and reported to EPA as part of the Complex Terrain Model Development\nprogram.\nThe gaseous tracer support for the ASCOT program is planned to continue\ninto October 1984. A reporting of the tracer releasing and sampling will be\nprepared.\nA description and listing of the meteorological and tracer gas data taken\nduring SEADEX will be provided to NRC, the sponsor.\nACID DEPOSITION\nAccomplishments FY 1984\nThere is no question that the acid rain problem has continued to be one of\nthe major environmental questions before the U.S. public. Heightened concerns,\nboth national and international, have been expressed with significant evidence\nof forest damage. These environmental attacks may be broader than just acid\nrain and could include the impact of other chemicals in the atmosphere, such as\nozone. Along with other ERL scientists, researchers in ARL have worked to pro-\nvide the best scientific input to decision-makers who must eventually decide on\nnational pollutant control strategies. Also considerable effort was put into\ninternational activities that involved both Canada and Europe. In the national\neffort under the Interagency Task Force on Acid Precipitation, ARL participa-\ntion has included taking an active leadership role in a number of areas.\nTo date, ARL's program has been involved in three research areas:\nNatural Sources, Atmospheric Processes, and Deposition Monitoring. In all\nthree areas, our program was given very high marks in the first program review\nof the Federal effort (Boston, 1983). Important progress has been made in\nparticular areas:\nNew analytical techniques for measuring sulfur-containing species were\ndeveloped and field tested.\nA special study was carried out to evaluate the inflow of natural\nacid-forming materials from the Gulf of Mexico.\nThe meteorological aspects of long-range transport during CAPTEX have\nbeen better defined using inert tracers.\nThe Western Atlantic Ocean Experiment (WATOX), which is aimed at\nmeasuring the flux of sulfur and nitrogen compounds off North America,\nproduced its first estimates of transboundary fluxes for these compounds.\nThe Global Trends Network, after three years of measurement, showed that\nthe acidity in remote areas was higher than generally expected and that\norganic acids were important in remote areas.\nDry deposition research progressed enough so that prototype monitors have\nbeen sent to the field for testing.\n156","Special studies at the atmospheric research sites included inter-\ncomparison of wet sampling procedures and the establishment of gas\nand aerosol measurements\nPlans FY 1985\nOngoing activities will be supplemented by the following new activities in\n1985:\nA major field experiment will be conducted during March/April 1985 under\nWATOX. Along with measurements from the King-Air, a special set of\nground measurements will be made along the East Coast and Bermuda.\nIn cooperation with EPA, mountain-top observatories to measure acid\ndeposition will be developed.\nPLUME TRANSPORT & DISPERSION\nAccomplishments FY 1984\nAvailable information on atmospheric turbulence in the Planetary Boundary\nLayer (PBL) has been re-examined, and a revised set of recommended procedures\nfor evaluating dispersion has been produced. These methods focus on the need to\ntake PBL scaling factors into account, even near the surface.\nWork on scaling the depth of the PBL is continuing. Numerical models are\nbeing used to investigate the relative importance of different factors, and sup-\nporting theoretical arguments are being developed. For the daytime case,\nclassical arguments concerning free convection form the basis for much of the\nnew work. For the nocturnal case, the roles of gravity waves and of decoupling\nnight are receiving most attention. A modified experimental program to\nat\ninvestigate the occurrence of turbulence intermittency during strongly stable\nconditions has been initiated as an outgrowth of the PBL monitoring program con-\nducted at Oak Ridge during previous years.\nThe automatic video digitization system developed during the last two years\nhas been used in a field study to investigate plume dispersion associated with\na\nlarge fire, in Virginia during 1983. Video records of the plume have been\nARL\nedited and are now available for distribution.\nThe Laboratory is continuing to play a role as a reviewer of alternative\nand potentially competing dispersion models. For purposes associated with\npower-plant siting, codes developed for the NRC have been examined in\nconsiderable detail. Possible sources of errors have been identified, and the\nconsequences of the most critical errors have been assessed for selected\ncircumstances.\nThe METREX study is explained elsewhere in this report. A team from Oak\nRidge has participated in most of the METREX experiments conducted to date. Oak\nRidge participation has been to provide information on the evolution of the PBL\nduring the performance of tracer release experiments.\n157","Plans FY 1985\nWork on evaluating methods for testing numerical models will continue.\nThe Laboratory will participate in a model evaluation workshop being organized\nfor early FY 1985 by the Savannah River Laboratory. The emphasis of the con-\ntribution will be on the theory and philosophy of model testing. Special at-\ntention will be given to the need to ensure that model outputs and experimental\ndata bases share important common features, arranged so that models are not\nasked to explain variations in nature that they are incapable of addressing.\nStudies of the effects and causes of nocturnal turbulent intermittency\nwill concentrate on the area surrounding Stone Mountain, Ga., where a\ncooperative study with Georgia Institute of Technology is about to commence.\nCOMPLEX TOPOGRAPHY\nAccomplishments FY 1984\nThe ATDD continues to contribute to the DOE's ASCOT program. A major\nfield study in northern Colorado took place at the close of FY 1984. A\npreliminary study, designed to get ready for the subsequent major investigation\nwas conducted during June, and several exploratory visits to the area in\nquestion were also conducted. A team of eleven ATDD scientists and technicians\noperated tethersonde profiling apparatus during periods of intensive study,\nand contributed some exploratory measurements of turbulent exchange in condi-\ntions of nocturnal drainage flow. A new focusing on quality assurance and\nquality control of experimental data was led by ATDD. A coordinated effort\nwas organized to compare data from different instruments, to provide standards\nfor comparison, and to guarantee that no erroneous values will be included in\nfinal data tabulations.\nAttempts to simulate flow features in complex terrain continue. A new\ndrainage flow model has been developed, compared with data obtained in\nselected circumstances, and coded in a way that will allow tests to be\nconducted using the newly obtained ASCOT field data.\nPlans FY 1985\nAnalysis of data obtained during the intensive field study conducted in\nSeptember-October 1984 will commence. Data will be reduced and summarized for\ninclusion in an official ASCOT publication. Selected subsets of the data will\nbe identified for use in testing and improving the drainage flow models deve-\nloped as a consequence of earlier research under this activity.\nAs FY 1985 progresses, the laboratory's role in designing and organizing\nfield studies under the ASCOT program will become increasingly important. By\nthe end of FY 1985, it is expected that ARL will have accepted the major burden\nof work related to field operations of the multilaboratory ASCOT program.\n158","ATMOSPHERE-CANOPY INTERACTION\n(FOREST METEROLOGY)\nAccomplishments FY 1984\nA study of the effects of forest structure, phenology, and Earth-Sun\ngeometry on the spatial, temporal, and spectral variability of deciduous forest\nradiation regimes was completed. Data collected were also used to evaluate\nseveral published phytoactinometric models. Results indicate that currently\navailable models of radiative transfer in plant canopies do not acceptably simu-\nlate deciduous forest radiation regimes during the fully-leafed phenological\nphase, largely because of clumping of foliage. The models tend to underesti-\nmate radiation penetration and overestimate canopy reflectance.\nAn investigation of thermal radiation within the deciduous forest canopy\nwas initiated. Data have been obtained in winter, spring, and summer in\nleafless, leaf expansion, and fully-leafed canopy states. A preliminary\nintensive study of thermal radiative transfers in the fully-leafed deciduous\nforest was conducted in collaboration with the Colorado State University, EG\nand G Energy Measurements Group in Las Vegas, and the Army Engineers Waterways\nExperiment Station. A similar series of measurements is planned for early in\n1985 in the leafless forest.\nPeriodic measurements of vertical turbulent exchanges of momentum,\nsensible and latent heat, and mass (specifically of carbon dioxide, ozone,\nsulfur dioxide, and various hydrocarbon and particulate species) continued,\nlargely in conjunction with studies of dry deposition. Fluxes of hydrocarbons\nwere observed above the spring leafless forest in collaboration with Brook-\nhaven National Laboratory. A major study of carbon dioxide fluxes was conduct-\ned in collaboration with the University of Nebraska. A comparison between\ndifferent fast-response carbon dioxide sensors was also conducted.\nDevelopment of models to describe interaction between a vegetative canopy\nand the atmosphere has been hindered by the lack of data describing turbulence\nwithin plant canopies. This matter has been a major concern, but the lack of\nadequate technology has prohibited the matter from being addressed directly\nuntil recently. Exploratory investigations of in-canopy turbulence and\nmicropressure fluctuations within the trunk space of the fully-leafed deciduous\nforest were made in early 1984.\nClimatological monitoring and data reduction for the Walker Branch decid-\nuous forest meteorology research site continued. The data set required for a\nclimatological assessment of bulk canopy radiative properties as a function of\nseason was completed, and data reduction is under way.\nARL\nThe group was host to an international conference on Forest Environmental\nMeasurements at Oak Ridge, Tenn., in October 1983. More than 80 scientists\nattended, from West Germany, Sweden, The Netherlands, Australia, England,\nFrance, Scotland, Belgium, Ivory Coast, Uganda, and Canada, as well as the\nUnited States.\n159","Plans FY 1985\nPeriodic measurements of vertical turbulent exchange above the deciduous\nforest canopy will continue with increasing emphasis on the effect exerted by\nthe canopy. In addition, greater emphasis will be placed on within-canopy flux\nmeasurements. The goal of these efforts will be to define relevant source and\nsink distributions.\nProcessing and analysis of data collected in previous studies of canopy-\natmosphere turbulent exchange will continue. Wind component data from near the\nforest floor will also be processed and interpreted. These analyses and\ninterpretations will help to define FY 1985 and later measurement programs.\nA study of the thermal radiation exchanges in the leafless forest canopy is\nnow being planned and will be performed in the winter of 1984-85.\nClimatological monitoring at the Walker Branch site will continue, with\nincreasing emphasis on the influence exerted by the biological (physiological)\nfunctioning of plant canopies on exchange between the atmosphere and the sur-\nface.\nDRY DEPOSITION\nAccomplishments FY 1984\nSince there is no instrumentation suitable for routinely monitoring dry\ndeposition, the national program to obtain dry deposition information on a\nroutine basis is designed to infer dry deposition fluxes from other\nquantities. Suitable methods have been developed at ATDD, and tested during\nthe last two years. A small network of prototype apparatus has been set up,\nat a total of five sites. Dry deposition flux estimates will be provided of\nsulfur dioxide, nitric acid vapor, and sulfate, nitrate, and other species\nassociated with submicron aerosol exchange. A sixth site will be added early\nin FY 1985.\nThree of the selected locations are research stations where direct measure-\nments of appropriate dry deposition fluxes are made at various times throughout\neach year, using micrometeorological methods or any other technique that pro-\nvides an independent measure of the dry deposition flux. These special core\nresearch sites are located at Oak Ridge, Tenn. Argonne, Ill. and State\nCollege, Pa. Several studies to evaluate dry deposition fluxes directly were\nconducted during the last ATDD-hosted field studies involving collaborators from\nArgonne National Laboratory, the University of Denver, and EPA's Environmental\nSciences Research Laboratory. In addition, ATDD participated in an intensive\nfield study conducted at State College, Pa., during the year.\nThe pilot dry deposition monitoring program is being conducted in close\ncollaboration with EPA, DOE, and USGS.\nA facility to evaluate data derived routinely at monitoring sites has been\nset up at ATDD. Models describing the exchange processes involved have been\n160","developed, coded, and simplified for routine application. The first routine\ndata tapes from the network pilot program were analyzed during August.\nPlans FY 1985\nSeveral additional pilot stations for deposition monitoring will be\nconstructed and distributed to locations where tests can be made against other\ntechniques. In particular, a collaborative program with USGS will be ini-\ntiated, to compare alternative dry deposition assessments at a calibrated\nwatershed adjacent to Panola State Park in Georgia.\nOperations at the three core research sites coordinated by ATDD will be\ndirected toward independent investigations of processes influencing dry\ndeposition, and toward a routinely scheduled program of intercomparison\nbetween direct methods of dry deposition flux measurement (e.g., snowpack\naccumulation and covariances) and the results of inferential techniques\n(especially concentration interpretation).\nMeasured atmospheric concentrations of selected trace gas and aerosol\nspecies will be documented routinely, together with the deposition velocity\ninformation needed to infer dry deposition rates. Data will be provided to EPA\nfor archiving as 1-week averages.\nOZONE\nAccomplishments FY 1984\nTotal-ozone and ozone-profile data for the world have been updated through\nthe summer of 1983. Ground-based and satellite measurements indicate a 5%-7%\ndecrease of total ozone in North America, Europe, and Asia in late 1982,\nresulting in record low (since 1958) total-ozone values in North America and the\nnorth temperate zone in early 1983. Total-ozone values appear to be returning\nto normal later in 1983. Umkehr and ozonesonde-derived estimates of layer-mean\nozone in the north temperate zone indicate that this decrease of total ozone was\nmostly due to large (10%-15%) ozone decreases in the low stratosphere, though\nthe contribution of the high stratosphere is not easily determined because of\nthe bias introduced into Umkehr observations by the stratospheric dust from El\nChichon. It is concluded that the decrease in total ozone in late 1982 was\nmore likely due to anomalies in atmospheric circulation than anomalies in the\nARL\nphotochemistry of the high stratosphere, but noted is the possibility that the\nvolanic eruption of El Chichon influenced the photochemistry of the low\nstratosphere.\nPlans FY 1985\nThe total ozone data and ozone-profile will continue to be updated to\nensure that the recent ozone decrease was indeed temporary and does not\nreflect photochemical influences on the high stratosphere.\n161","AIR QUALITY MEASUREMENTS\nAccomplishments FY 1984\nEvaluation of data from the 1983 Whiteface Mountain study was concluded\nduring 1984. Analysis of two-stage Nuclepore filters by proton-induced X-ray\nemission (PIXE) spectroscopy showed that most (85%-90%) of the aerosol sulfate\nwas in the accumulation mode and that approximately 90% of total sulfate\noriginated west and southwest of the Whiteface Mountain site. Scavenging of\nsulfate aerosol by clouds was found to be quite efficient, i.e., greater than\n95% in clouds of 0.5 g m-3 liquid water content. Cloud-rainwater samples from\nwest-southwest industrial regions had the highest concentrations of SO4 ,\nNO3\n, Pb, Ba, and Ca , but samples from the west-northwest had the highest\nconcentrations of Cd, Mn, Sr, F-, , and K.\nThe ratios of measured pH to pH calculated from the sum of sulfate and\nnitrate, or to the sum of anion minus cation concentrations were usually about\n1.05; i.e., the calculated acidity was slightly greater than the measured\nvalue. However, in most of the samples from polluted systems the ratios were\nsignificantly less than 1. Organic acids are believed to constitute the unac-\ncounted acidity in the measured samples.\nA possible mechanism has been identified whereby concentration of dissolved\nsubstances can occur on the surfaces of exposed vegetation, especially on the\nneedles of coniferous trees. Along with this identification is the information\nthat the effect on vegetation is mostly dependent upon cloud acidity near the\ntermination of cloud exposure.\nIn an experiment conducted at the Boulder Atmospheric Observatory 300-m\ntower, in an airmass with sulfate concentration less than 1 g m =3 particulate\nmatter of diameter D < 3 m was collected to afford 1-h increment data analysis\nfor sulfur and soil by PIXE analysis. In-cloud removal efficiencies of ini-\ntially dry aerosol were 80%-98% for sulfur and 35%-77% for soil aerosol.\nTotal accumulation mode mass was reduced by >90% following cloud development.\nNucleation scavenging appears to be the dominant mechanism by which precipita-\ntion sulfate was formed.\nA Beech King-Air C-90 twin-engined aircraft was obtained by interagency\nagreement from the Department of the Interior and was equipped for aerosol\nsize distribution measurements, aerosol filter sample collections, gas sample\ncollections, in situ analysis of some trace sulfur-containing gases, and in\nsitu analysis of ozone.\nPreliminary results from measurements in and immediately above the boundary\nlayer near the Louisiana coast during August and early September 1984, indicate\nthat the concentration of dimethyl sulfide (DMS) in the clean marine atmos-\npheric boundary layer was 37 + 29 pptv, but that when offshore air flow\ncarried continental air to the same location (i.e., 20-50 miles offshore), the\nDMS concentration was reduced to 6 + 3 pptv. The clean air value is in\nreasonable agreement with reported mid-Pacific ocean surface measurements, but\ngreater than reported Gulf of Mexico concentrations (<10 pptv). The\n\"continental air\" was identified as such on the basis of factor-of-2-to-4\ngreater concentrations of CO and non-methane hydrocarbons. This air had\nnecessarily crossed the DMS-productive coastal zone and had presumably\n162","received a similar DMS input from the Gulf as had the \"clean air\" samples.\nHowever, the higher concentrations of CO imply proportionately higher\nconcentrations of hydroxyl radical, OH, and therefore a higher destruction\nrate for DMS.\nIn all samples from above the boundary layer the DMS concentration was\nless than the analytical limit of detection.\nPreliminary measurements of several physical and chemical parameters, asso-\nciated with clouds, in two cases of onshore flow of air across the Washington\ncoast were performed in cooperation with the Atmospheric Science Department,\nUniversity of Washington. The data suggest that the physical and chemical prop-\nerties of Pacific maritime, cloudy air passing over this region change over\nrelatively small spatial and temporal scales ( 100-200 km and 5-15 h) This\ntentative conclusion concerning the scales for air mass changes differs from\nthe assumption usually made of air mass characteristics and transport\ndistances in the eastern United States.\nPlans FY 1985\nResearch will continue on quantification of the concentrations of sulfur-\ncontaining acid precursor gases and acidic aerosols in the marine environment,\nnear the coastal zones, and inland in areas of climatological inflow for\nmarine air masses that traverse large areas of the continental United States.\nThe work will be concentrated at the continental boundary of the Gulf of\nMexico; the Atlantic states south coastal region and the Pacific northwest\ncoastal regions are also significant inflow areas, and may be included in the\nmeasurements. The Gulf effort will be conducted during late spring, summer,\nand early autumn, when the probability is greatest of finding onshore-moving\nair masses.\nSimilar research will be conducted at the middle Atlantic coastline, during\nboth winter and summer, during periods of continental air outflow to the ocean\natmosphere. The research will be carried out through use of a twin-engined\naircraft equipped for in situ and/or laboratory measurements of trace sulfur-\ncontaining gases; for in situ ozone analysis; for filter collection of aerosols\nto be analyzed later for sulfate, nitrate, chloride, bromide, and sulfur\ndioxide; for in situ measurement of temperature, dew point, and aerosol size\ndistributions.\nThe flux of acids and acid precursors into the midwestern and eastern\nUnited States, as well as the flux outward from the east coast, will be\nARL\nestimated.\nResearch will be conducted in the Grand Canyon to determine air flow pat-\nterns associated with definable meteorological conditions and with solar heating\nof canyon walls. This work will be carried out with an aircraft equipped with\nside-looking radiometers for measurement of canyon wall temperatures, and with\nDoppler radar and a gust probe for the measurement of atmospheric turbulence.\nOutput from this project will assist National Park Service personnel in iden-\ntifying times when atmospheric conditions are suitable to conduct understory\nburning and other necessary forest management practices without adversely\naffecting visibility and visual range in this important Class I visibility\narea.\n163","AIR QUALITY DISPERSION MODELING\nAccomplishments FY 1984\nThe major emphasis in NOAA support to the EPA research program continued\nto be the development and evaluation of air quality simulation and\nmeteorological models, including the collection of critical data bases. The\nrange of activities was wide.\nA multiyear effort to implement the first generation Regional Oxidant\nModel (ROM) was completed. The model was applied to a simulation of the\nnortheastern United States during the period 3-5 August 1979, which is one of\nthe high ozone periods investigated in field experiments by the Northeast\nRegional Oxidation Study (NEROS) and the Prolonged Episode Pollution\nExperiment (PEPE). The simulation showed that the bulk of the air mass\npresent in the region when the simulation began was still within the domain\nafter 36 hours. The highest ozone concentration predicted by the model was\n230 ppb over Lake Erie on the second day of the simulation. Aircraft data\nsupport this prediction. An extensive verification and archive system was\ndeveloped to prepare raw data collected during the NEROS field studies for use\nin the ROM. Standard procedures for verification of meteorological data were\ncompleted. Raw data for 3-5 August have been processed, and work is\ncontinuing on the remaining data collected during the 1979 and 1980 field\nstudies. A computer module that generates hourly 1/6° latitude_x 1/4°\nlongitude gridded dry deposition velocity maps for SO2, and S04 for the\neastern United States (105°W-66°W, 24°N-50°N) has been produced. The\ninfluence of temporal variations in surface boundary layer flow on deposition\nis handled using state-of-the-art parameterization schemes.\nFurther, variations in surface characteristics and vegetation are explic-\nitly handled by a matrix relationship developed for nine individual land use\ncategories as used in the ROM. A final value, unique to each grid, is a\ncomposite of individual subgrid land use values apportioned by percentage of\nareal coverage. The Biogenic Emissions Software System has been upgraded to\nprovide (1) variation of emission factors by temperature and light intensity\nand (2) direct calculation of biomass as a function of tree diameter. The\nin-house contractor has submitted a draft report documenting the function and\noperation of the system.\nDuring FY 1984 the spatial and temporal characteristics of the New York\nCity and Boston ozone plumes, the magnitude of ozone and precursors transported\ninto these cities, and the relationships between surface ozone concentrations\nand mixed-layer values were investigated.\nA relatively simple Photochemical Box Model (PBM) was developed for use in\nscreening high level 03 episodes during stagnant conditions in urban areas.\nThe PBM is a mass-conservative numerical model and requires inputs of\nhour-averaged emissions, meteorological parameters, and boundary\nconcentrations to produce hour-averaged O3 concentrations for the box volume;\na User's Guide provides guidance on using the PBM.\nAn investigation into the performance of short-term, urban, photochemical,\nair quality simulation models for NO2 predictions was performed. The study,\nwhich was a reanalysis of results for three models previously evaluated for\n164","their performance of short-term 03 predictions, showed that serious problems\nremain in using these models for NO2 and that the St. Louis Regional Air\nPollution Study base was too deficient in high hour-average NO2 values for use\nas a test bed for NO2 model performance.\nA model was developed describing the diurnal behavior of the layer of\nsurface-based turbulent mixing and the winds and temperatures averaged over\nthis layer. The model also represented the conditions at the top of the\nmixing layer by time-dependent equations for the wind and temperature. The\nsurface heat flux and friction velocity were both well represented by the\nmodel when compared with actual measurements taken on Day 33 of the Wangara,\nAustralia, field experiment. These results show that it is possible to use a\nsingle layer for the modeling of the diurnal behavior of the mixing layer as\nlong as conditions at the top of the layer are also included. This allows for\nsome representation of the nocturnal gradients in wind and temperature.\nNumerical experiments were conducted to compare several different methods\nof handling the horizontal advection of material in mass-conserving gridded air\nquality models. The results show that the FCT algorithm preserves the peak con-\ncentration areas better than the SHASTA algorithm, although it requires more\ncomputation time, and the BIQUINTIC algorithm, which requires the most com-\nputation time of the methods studied, may be preferable in some models because\nof its independence of restrictions on step size.\nVertical velocity turbulence data collected by an instrumented aircraft on\nhorizontal flight paths over the St. Louis metropolitan area have been exten-\nsively analyzed to determine spatial variations in vertical velocity statistics\nand length scales in the urban convective boundary layer. Results support\nlaboratory numerical model results, which indicate more time is spent in\ndescending motions with positively skewed vertical velocity distributions in a\nconvective boundary layer. Magnitudes of vertical statistics and the peak wave\nlength of the vertical velocity spectrum were greater in urban than in\nnonurban locales.\nThrough use of a simple inversion rise model, surface-layer values, flux-\nprofile relationships, and similarity scaling laws for the convective\natmospheric boundary layer, it was shown that meteorological parameters for\ndispersion models can be deduced using simple and readily available measure-\nments. The required parameters are mixing height and profiles of wind speed,\nwind direction, horizontal turbulence, and vertical turbulence. Available\nmeasurements include the early morning temperature profile from a radiosonde\nascent; single-level surface-layer values of wind speed, wind direction, and\nhorizontal turbulence, two levels of mean temperature near the surface; and an\nARL\nestimate of local surface roughness. Except for wind direction each of the\nrequired parameters can be estimated with an average error of 10% to 30%.\nA routinely applied atmospheric dispersion model was modified to evaluate\nalternative modeling techniques that allow for more detailed source data, onsite\nmeteorological data, and several dispersion methodologies, using data for two\nTVA powerplants. A significant finding was that more sophisticated models did\nnot appreciably outperform the routinely applied models, perhaps, in part,\nbecause the lateral standard deviation of wind direction available was the 1-h\naverage of 5-min values (rather than a 1-h value), thus eliminating the longer\nperiod fluctuations that are important in estimating 1-h concentrations in\naddition to the shorter-period fluctuations.\n165","A system of meteorological processors that provides a choice of method-\nologies for computing meteorological parameters required as input to the\ncomputer code has been completed. The Branching Trajectory Model, which re-\nplaces Heffter's trajectory model, has been installed and the Complex I and II\nmodels extensively tested. A new method for ozone exposure estimates provid-\ning characterization of hourly frequency distributions has been proposed.\nMajor modifications have been made to MESOPUFF, a Lagrangian, variable\ntrajectory, puff superposition model, to enhance its capability for treating\ntemporal changes and spatial variations in the transport, chemical trans-\nformation, and wet and dry deposition processes of sulfates and nitrates from\nmultiple point and area sources. The methodologies incorporated into the\nmodified version, designated as MESOPUFF II, and preliminary evaluation of\nseveral model algorithms are documented in a project report. A user guide\ncontains instructions and examples of input data and output results.\nThe Pollution Episodic Model (PEM), an urban particulate model that treats\nthe transport, dispersion, chemical transformation, and dry removal processes\nfor one or two reactive or nonreactive pollutants for up to 24 hours, was\nevaluated with measurements from the St. Louis Regional Air Pollution Study.\nResults of 20 cases show that PEM predicted 12-h average concentrations of SO2\nand fine and coarse sulfates to within a factor of 2, while fine and coarse\ntotal particulate mass concentrations were overestimated by factors of 3 to 4.\nThe ENAMAP-2 model has been completely rewritten to correct known defects\nand add several features. The new model uses a three-layer puff during the\nday and a four-layer puff at night. Mixing heights, deposition parameters,\nand grid correction factors vary from grid to grid, and mixing height may vary\ndiurnally and seasonally.\nA user's guide for INPUFF, a single source, Gaussian, puff dispersion\nalgorithm, was completed. INPUFF is an integrated puff model primarily for\napplications where plume models are not applicable. It is designed to model\nsemi-instantaneous or continuous point sources over a spatially and\ntemporarily variable wind field. INPUFF was executed using the Savannah River\nLaboratory's Mesoscale Atmospheric Transport Studies data base. The data base\nconsisted of data from 15-min releases of SF6 over 14 days during 1983, along\nwith aerometric and upper-air data. The results of the model runs were sent\nto Savannah River Laboratory in June 1984. Results of the INPUFF and other\nmodel runs will be compared at the DOE - American Meteorological Society Air\nPollution Model Evaluation Workshop in October 1984.\nAn evaluation of commercially available sodar looked at the ability to\nmeasure wind speed, direction, and vertical turbulence at heights to 300\nmeters. Findings from comparisons with sonic anemometer measurements on the\nNOAA Boulder Atmospheric Observatory tower indicate that wind speed and\ndirection are measured reasonably well, but that the turbulence measurements\nhave relatively large scatter.\nData from the National Crop Loss Assessment Network were modeled with a new\nmathematical model based on a previous leaf injury model. The model estimated\nreductions in crop yield for seven plant species for each of the 1,824 site-\nyears of 1981-1983 hourly 03 concentration data available in the National\nAerometric Data Bank. Ambient 03 concentrations reduced the total U.S. crop\nyield an estimated 5% for years 1981-1983.\n166","Plans FY 1985\nDirect meteorological research support to EPA will continue on the develop-\nment and evaluation of air quality dispersion models for inert and reactive\npollutants and the associated meteorological models on all temporal and spatial\nscales, using available data bases. An important area of concern will be the\nproblems associated with model uncertainty and model evaluation procedures.\nThis includes development and evaluation of urban dispersion models for ozone\nand particulate matter; preparation of an assessment of diffusion research\nstatus and needs; continued work on development of a regional scale, particulate\nmatter, dispersion model; completion of a revised climatological dispersion\nmodel; study of the problem of extrapolating turbulent fluctuation with height;\ndevelopment and evaluation of a second-generation ROM; and various transport,\ndeposition, and diffusion studies.\nFLUID MODELING\nAccomplishments FY 1984\nStudies continued to be conducted in the EPA Fluid Modeling Facility, con-\nsisting of a water channel/towing tank and one large and two small wind tunnels,\nin support of the EPA research program. A major effort in 1984 was the study of\nflow in complex terrain.\nA series of tows was conducted in the stably stratified saltwater towing\ntank to test the validity of the assumption of a dividing streamline (a flat\nsurface that divides to go around opposite sides of a topographic obstacle) as\ncurrently used in several complex terrain models. This assumption allows\nmodelers to simply divide the flow field into two regimes: a horizontal flow\nin a lower layer and potential flow in an upper layer. One set of tows was\nmade normally (inverted model) with a dividing-streamline height of half the\nhill height (h), effluent was released at 0.6, 0.7, and 0.8 h, and the\nresulting hill-surface concentration patterns were measured; a second set of\ntows was made under identical conditions except that the model was raised out\nof the water to the point where the water surface was precisely at the\ndividing-streamline height (i.e., half the hill height), thus forcing a flat\ndividing-streamline surface (the water surface). Comparison of the two sets\nof surface concentration patterns suggested that the flat dividing-streamline\nassumption is quite reasonable.\nARL\nRecent wind-tunnel and towing tank studies on aerodynamics and plume\ndispersion in complex terrain were designed to contain basic physical\nunderstanding of flow structure and diffusion, to provide guidance in locating\nsources, and to provide \"rules-of-thumb\" for estimating surface concentrations\nwhen a source is located in complex terrain. Terrain amplification factors were\ncompiled for a large variety of hill shapes, slopes, aspect ratios, and source\npositions from the neutral wind tunnel studies. From the stratified towing-tank\nstudies, the dividing-streamline concept was shown to be a highly useful indica-\ntor in determining whether a plume would impact on a hill surface or surmount\nthe top. Limitations of the towing tank for simulating strongly stratified\nflows over two-dimensional hills were also pointed out.\n167","Stable atmospheric flow over a ridge and a valley was simulated in the\nsaltwater-stratified towing tank. Flow visualization experiments were\nconducted using dye streamers and models with sinusoidal cross sections to\nprovide qualitative data on the structure of the flow field over the ridges\nand within valleys, as well as quantitative data on the height of the dividing\nstreamline. These data agree with existing theories based upon the potential\nenergy barrier associated with flow over a ridge.\nAdditional experiments were conducted to test the feasibility of towing-\ntank simulations of strongly stable atmospheric flows over very long (two-\ndimensional) ridges. They showed that steady-state conditions are not\nestablished in a finite length towing tank and, hence, cast doubt upon the\nvalidity of previous laboratory studies.\nA wind-tunnel study was conducted of dispersion from a source upwind of a\nthree-dimensional hill of moderate slope. The study was specifically designed\nto examine the deformations of the plume effected by the hill, and to aid the\nmathematical modelers in developing and testing their complex terrain models.\nUnder a cooperative agreement with the North Carolina State University, a\nwind tunnel study was conducted to examine the flow structure and dispersion in\nthe wakes of axisymmetric hills. Two conical hill shapes with slopes of 17° and\n25° were used. Pollutant sources were placed on the tops and at the downwind\nbases of these hills.\nA wind tunnel study was conducted in response to a request from EPA with\nregard to revisions of the good-engineering-practice (GEP) regulations on\nstack height. Terrain amplification factors were measured for a large matrix of\nsource positions (locations and heights) both upstream and downstream of each of\ntwo idealized model hills, an axisymmetric hill and a two-dimensional ridge.\nThe results showed that a \"window\" of 40% excess concentration extended to 1.8\nhill heights (h) in the vertical, 14 h upstream and 10 h downstream for the\nthree-dimensional hill, and 2.2 h in the vertical, 8 h upstream, and 15 h\ndownstream for the two-dimensional ridge. Maximum terrain amplification factors\nwere found on the downstream sides of the hills, with values of 6.8 and 5.6 for\nthe 2-D and 3-D hills, respectively.\nA 2-month study of concentration and velocity profiles downwind of isolated\nblock buildings was conducted in the meteorological wind tunnel. Measurements\nof concentrations and velocity will be used to delineate the effects of building\nscale, building orientation, wind speed, and boundary layer characteristics on\ntheir nondimensional distributions.\nMethodologies for analyzing videotaped images of smoke-visualized plumes\nare being developed. A sample videotape of a plume in the wake of a block\nbuilding was recorded in the EPA Fluid Modeling Facility's meteorological wind\ntunnel. This tape is being used to assess the capabilities of video digitiza-\ntion equipment at North Carolina State University.\nA Quality Assurance Plan was prepared for the Fluid Modeling Facility.\nThis plan specifies the standard operating procedures for the facility's wind\ntunnels, water channel/towing tank, and associated equipment and instrumen-\ntation. These procedures are to be followed in order to ensure that (a) proper\ntechniques are applied in the acquisition of data, (b) traceability of data is\nmaintained, and (c) quality assurance techniques can be applied in assessing the\naccuracy, reliability, and representativeness of acquired data.\n168","Under a cooperative agreement with the North Carolina State University,\nthe first phase of a wind tunnel study was conducted to examine the effective-\nness of screens in reducing wind speeds near storage piles. This provides\nan intermediate step in constructing a mathematical model to predict the effec-\ntiveness of the screens in reducing fugitive dust emissions. Various screen\ntypes, placements, shapes, and sizes were tested, and a paper was presented\nfor one shape of storage pile (an idealized conical shape) Contour maps\nof\nsurface wind speed reduction factors were prepared showing that, as expected,\nthe more material (i.e., the larger the size or the lower the porosity), the\nmore effective was the screen in reducing wind speeds.\nPlans FY 1985\nWork will continue in the Fluid Modeling Facility, using the wind tunnels\nand water channel/towing tank, on the study of flow in complex terrain, around\nbuildings, and in the wake of automobiles. This includes studies of flow and\ndiffusion in the wakes of three-dimensional hills; effects of shear and hill\nslope on upwind vortex formation; wake of streamlined vehicles in a shear-free\nboundary flow; GEP stack heights with respect to complex terrain and influence\nof obstacles/buildings on plume dispersion and meander.\nACID RAIN MODELING\nAccomplishments FY 1984\nA major effort is under way, in support of the EPA research program, to\ndevelop and evaluate regional and mesoscale acid deposition models. The compre-\nhensive regional model is being developed at the National Center for Atmospheric\nResearch (NCAR) through an agreement with the National Science Foundation. Some\nof the component modules are under development at several of the DOE National\nLaboratories. Module development included both field studies and numerical\nmodeling activities in FY 1984.\nThe development of a regional acid deposition assessment model at NCAR con-\ntinues on schedule. The mesoscale meteorological components are completed, and\nthree-dimensional meteorological fields to drive the chemical/transport of the\nmodel are being generated for representative episodes. A preliminary version of\nthe gas phase chemical schemes has been completed and documented.\nARL\nObservations using NASA's airborne UV DIAL (differential absorption lidar)\nsystem provide new and convincing evidence to substantiate the hypothesis that\nvertical transport of pollutant materials out of the mixed layer does occur by\npenetrative cumulus convective clouds. Horizontal transects were flown above\nan air mass known to have experienced active cumulus clouds earlier. The\nrange-resolved measurements show the aerosol and ozone concentration of the\ndissipated cloud field to be well above background, comparable with mixed\nlayer values and highly correlated and organized in tilted layers.\nA major program to study and to model the transport and transformation of\nmixed-layer pollutants by nonprecipitating cumulus convective clouds is under\n169","way. A large field study, VENTEX-84 (VENTing EXperiment) was conducted in July\nand August 1984 in the vicinity of Lexington, Ky. Observational components of\nthis coordinated study include boundary layer and cloud mass inflow measurements\nby Argonne National Laboratory, cloud population and special cloud dimension\nstatistics by Research Triangle Institute, mixed and cloud layer structure,\nand data to compute mass flow rates between the mixed and cloud layer\ninterfaces, as well as transformation rates resulting from cumulus clouds by\nPacific National Laboratory personnel. Parameterization based on these\nstudies will be incorporated into a computer module for use in regional scale\ntransport and deposition models.\nA field program to study the effect of the emissions from a large urban\narea on downwind acid deposition was carried out in the Philadelphia metropoli-\ntan area. A network of wetfall samplers in a control area in southern New\nJersey, and another network in a target area in southeastern Pennsylvania were\nused to collect rainfall. The results show that there can be as much as a\nfactor-of-2 increase in nitrate deposition and a smaller increase in sulfate\ndeposition under the conditions of the experimental design, namely, an easterly\ntransport flow with steady rainfall. The maximum impact of the urban area must\noccur beyond 60 km from the city. Other related activities included a new\nregional-scale tetroon-tracking system based on loran-C navigational stations\nwas developed in cooperation with ARL's Field Research Division. The system\nwas deployed in support of CAPTEX '83. The resulting data have been\ndocumented and are included in the CAPTEX data base.\nAn airborne, two-wavelength lidar has been modified to detect the\npresence of fluorescent dye particles (FDP). This new technique can be\napplied to track the movement and dispersion of air parcels spiked with a\ncloud of FDP on regional transport scales. A successful field demonstration\nwas performed in association with CAPTEX '83. During this initial study,\ndiscrete-circular clouds of FDP released over Ohio were successfully tracked\nover the Appalachian Mountains and were observed to be stretched in the\nlongitudinal direction.\nA new statistical procedure, which gives optimum interpolation weights and\nconfidence limits on the interpolated surface, has been applied to acid deposi-\ntion data. Results indicate that isopleth maps of acid deposition have a great\ndeal of uncertainty in the position of the isopleths. As a result, small year-\nto-year changes in isopleth position are generally not significant. These\nresults have important consequences in model validation as well as data\nanalysis.\nThe Eastern North American Model of Air Pollution (ENAMAP) was modified to\nimprove the organization and physical parameterizations. The modified version\nhas been tested using ambient SO2 and SO4 concentrations and sulfur wet\ndeposition data obtained during July 1978. Model input data for 1980 have\nbeen processed for model participation in the joint EPA-Environment Canada\nInternational Sulfur Deposition Model Evaluation Project.\nA group of European, Canadian, and U.S. regional sulfur deposition\nmodelers have been assembled to simulate 1980 ambient concentrations, and dry\nand wet depositions of SO2 and S04 across eastern North America. Standardized\ndata sets for model input have been processed, and a draft report describing\nthe study and the model input/output data sets has been completed. A panel of\n170","U.S. and Canadian statisticians has constructed the model evaluation framework.\nEvaluations will involve traditional descriptive statistics plus innovative\nanalysis procedures.\nA workshop was conducted at Woods Hole during September 1984 on Sources and\nEvaluation of Uncertainty in Long-Range Transport Models. The workshop was\narranged by the American Meteorological Society under the joint sponsorship of\nthe United States and Canada, an outgrowth of the previous U.S./Canadian\nMemorandum of Understanding on Transboundary Air Pollution.\nA contract was negotiated with TRC Environmental Consultants, Inc., to pre-\npare a design plan for a comprehensive field study to relate pollutant sources\nto acidic deposition. The plan, which recommends a nested-grid approach for\nmeasurements focused on individual sensitive receptor areas, was provided in\nSeptember. Work on this contract continues, as sensitivity analyses are\ndefining uncertainties involved with model input parameters.\nAn ARL representative served on special assignment as Chairman of the\nAtmospheric Processes Task Group C under the National Acid Precipitation\nAssessment Program (NAPAP). In this role, the Chairman established the inter-\nagency research plan for FY-1986 in concert with the NAPAP Task Force and the\nnine remaining Task Groups. The Chairman was also responsible for monitoring\nthe ongoing FY-1984 research activities and for updating the FY-1985\ninteragency research plans.\nPlans FY 1985\nWork on the development of the Regional Acid Deposition Model and its\nmodules will continue. Work on the development and evaluation of the\nmesoscale acid deposition and assessment model will expand with additional\nfield work near Philadelphia, and with an increase in modeling activities\nusing the data already available. Some of the mesoscale modeling activities\nwill be conducted with the assistance of NASA. The results of the AMS\nworkshop on Sources and Evaluation of Uncertainty in Long-Range Transport\nModels will become available. Activities associated with the International\nSulfur Deposition Model Evaluation will continue.\nDISPERSION IN COMPLEX TERRAIN\nARL\nAccomplishments FY 1984\nWork continued on two major field and modeling programs to study the\ndispersion of pollutants in complex terrain. These programs support the EPA\nresearch program. The Complex Terrain Model Development Program is a\nmultiyear field and modeling effort to examine and model the impact of\npowerplant plumes in mountainous terrain. Field studies were conducted in\nprevious fiscal years at Cinder Cone Butte in Idaho and Hogback Ridge in New\nMexico. In 1984 during August, 128 hours of dual-tracer and smoke diffusion\nexperiments were conducted from the Tracy powerplant near Reno, Nevada. Gas\nchromatographic analyses from the 110 samplers, located within 10 km of the\n171","plant, were excellent. Groundbased and airborne lidar measurements and\nphotographs of the smoke plume were obtained also. These data, supported by\nextensive meteorological measurements, provide significant input to the\nComplex Terrain Model Development Program.\nA scientific assessment established the applicability of existing complex\nterrain models for EPA regulatory use and summarized the current status and\nneeds for additional research.\nPlans FY 1985\nWork will continue on the development and evaluation of the Complex\nTerrain Model using the data base collected in physical modeling experiments\nin the Fluid Modeling Facility, and in the field at Cinder Cone Butte, Hogback\nRidge, and the Tracy powerplant.\nCLIMATE\nSUN-CLIMATE RELATIONSHIPS\nAccomplishments FY 1984\nThe Sun-Climate Staff completed analysis of solar UV radiation observa-\ntions from the Nimbus-7 satellite in the 160-400 nm wavelength range for the\nsecond year of these measurements, and at the selected wavelength of 200 nm\nfor the first 4 years of observations. These radiations control the produc-\ntion of ozone and heating in the stratosphere, which may modulate tropospheric\nplanetary waves and influence climate. Previous studies of short-term (13-day\nand 27-day periodicity) UV variations caused by solar rotation and active\nregion evolution were expanded to include extensive statistical studies of the\ntime and frequency domain characteristics of these short-term variations.\nIntermediate-term variations lasting 4 to 8 weeks, which in 1979 and 1980\nhappened to be approximately semiannual variations, have been studied in the\n205-nm flux for 1979-1982, through the peak of solar cycle 21. The solar\ncycle variation of the UV flux peaks approximately 2 years later than the peak\nof the sunspot cycle. The solar UV flux model based on solar plage data gives\na current solar cycle variation of about 25% at 205 nm. Comparisons of the\nmodel with 4 years of 205-nm observations suggest that the model overestimates\nthe solar cycle variation. Employing 8 years of ground-based measurements of\nthe chromospheric solar infrared line of helium near 1 um in wavelength to\nestimate the 205-nm UV flux from their relation during the 4 years of UV\nmeasurements gives about 13% for the current cycle.\nThe rocket-flight UV spectroradiometers were tested and preliminary\ncalibrations conducted. Problems with too high a value of scattered light were\ndetected, analyzed, and then corrected by adding a state-of-the-art blackening\nto the internal non-optical structures and by adding several stray-light\nbaffles. The instruments have now been prepared for final calibration.\n172","Studies continued of the association of U.S. climatic anomalies with\nmeteorological and oceanographic conditions in the tropical Pacific. It was\nfound that the onset of below normal summer precipitation in the wheat-belt\nstates during the 1950's and 1970's occurred subsequent to (1) above normal\ntemperatures in the tropical Pacific the preceding winter, and (2) the\noccurrence of a \"minor\" sunspot maximum. On this basis, below-normal summer\nprecipitation in the Wheat Belt has been predicted for 1990 or 1991 and for\nthe four summers that follow.\nStudies have shown that precipitation over certain regions of the United\nStates varies with the phase of the lunar synodic (29.531 day) cycle. For\nexample, in Georgia during winter, precipitation of more than a few tenths of an\ninch per day is 30% more frequent during and immediately following full moon\nthan during other phases of the synodic period. This lunar phase dependence\nchanges during the other seasons.\nThe use of specification models continues in the development of experimen-\ntal monthly temperature and precipitation outlooks for the United States.\nOutlooks are provided to the National Climate Program Office, the Climate\nAnalysis Center of the National Weather Service, and ERL at Boulder, Colo.\nThe University of Arizona, under a NOAA grant, has completed development of\na ground-based solar spectrometer to measure solar spectral variability. It\nwill be deployed in Mt. Lemon, near Tucson, Ariz., in September 1984, and\nmeasurements will be initiated.\nPlans FY 1985\nIn cooperation with NESDIS, we will analyze the solar UV flux\nmeasurements in the 160-400 nm wavelength range from the SBUV/2 ozone monitor\nthat is to be flown on the NOAA satellite series as a joint NASA and NOAA\neffort starting in FY 1985. Analysis of Nimbus-7 and other satellite\nmeasurements of the solar UV flux will be continued with emphasis on trying to\nimprove our estimate of the solar cycle variation. Intermediate-term UV\nvariations (several months) will be studied in an effort to try to improve our\nmodel of these variations and to clarify the differences in their\ncharacteristics from those of associated intermediate-tern variations in the\nclassical solar activity indices, the 10-cm radio flux and sunspot number.\nThe main calibrations of the solar UV spectroradiometers will be completed.\nStratospheric temperature and ozone data measured concurrently with the solar\nUV flux will be studied to identify their reponses to UV flux variations for\nARL\nshort and intermediate-ter variations.\nBasic research will continue on the identification of climatic\nvariability with solar, lunar, and other periods and of causes and mechanisms\nfor these climatic changes. Specifically, the sensitivity of precipitation in\nthe United States to gravitational tidal forcing will be evaluated.\nMeasurements of solar spectral variability will continue on Mt. Lemon\nduring the year.\n173","TEMPERATURE\nAccomplishments FY 1984\nGlobal temperatures obtained from the 63-station radiosonde network have\nbeen updated through the spring of 1984, and are in the process of being updated\nthrough the summer of 1984. Despite the eruption of El Chichon (Mexico) in\nthe spring of 1982, Northern Hemisphere surface temperatures were 0.5°C above\naverage, and tropospheric 850-300 mb temperatures 0.4°C above average, during\n1983. However, temperatures in the 300-100 mb \"tropopause layer\" were 0.3°C\nbelow average, and in the low-stratospheric 100-30 mb layer 0.4°C below\naverage, during 1983; these latter show that the stratospheric warming induced\nby El Chichon has completely disappeared. The combination of warm troposphere\nand cool stratosphere means that the Northern Hemisphere lapse rate was\ngreater than normal in 1983. Tropospheric temperatures were lower in the\nwinter and spring of 1984, suggesting that the El Chichon dust cloud may\nfinally be having a cooling effect on hemispheric temperatures now that\nsea-surface temperatures in the eastern equatorial Pacific have returned to\nnormal following the pronounced El Niño episode.\nPlans FY 1985\nThe temperature data in troposphere and stratosphere will continue to be\nupdated throughout the world, with emphasis on detection of tropospheric\ncooling due to the El Chichon eruption.\nSUNSHINE DURATION AND CLOUDINESS\nAccomplishments FY 1984\nSunshine duration and cloudiness data for the contiguous United States\nhave been updated through the summer of 1983. In 1982 cloudiness was 5% above\naverage and sunshine 3% below average, apparently the result of the very warm\nsea-surface temperatures in the eastern equatorial Pacific (E1 Niño). By the\nsummer of 1983, these anomalies were diminished. During the last 30 years,\nthere has been a significant tendency for U.S. cloudiness to be above average\n(and sunshine below average) in years when Indian summer-monsoon rainfall is\nbelow average, and vice versa. However, there is no evidence that United\nStates cloudiness and sunshine are related to the quasi-biennial oscillation\nin the tropical stratosphere, or Northern Hemisphere surface temperature.\nPlans FY 1985\nSunshine duration and cloudiness data for the United States will continue\nto be updated to ensure that the large increase in cloudiness, and decrease in\nsunshine, in 1982 was indeed due to El Niño.\n174","HUMIDITY\nAccomplishments FY 1984\nBecause of questions concerning the representativeness and significance\nof humidity changes measured by radiosonde, the evaluation of humidity at the\n63-station radiosonde network is just commencing. The necessity of obtaining\nhumidity data at significant points as well as at the mandatory pressure sur-\nfaces is still under consideration.\nPlans FY 1985\nRelative humidity, mixing ratio, and precipitable water will be monitored\nat the same 63 radiosonde stations used for temperature monitoring.\nSOLAR RADIATION FACILITY\nAccomplishments FY 1984\nPyranometers were replaced at all 38 network stations, and pyrheliometers\nwere replaced at 10 stations. Recalibration of the old pyranometers that were\ninstalled in 1982 is in progress; early results show that for 17 instruments\nof one type the ratio of 1984/1982 calibrations is .993. and for 4 instruments\nof the second type the ratio is 0.981, confirming the 1% per year degradation\nfound previously. For four pyrheliometers recalibrated the average ratio is\n.995.\nThe Sixth New River Intercomparison of Pyrheliometers was held at the\nDesert Sunshine Exposure Test Laboratories near Phoenix in November 1983.\nDespite the high quality of these intercomparisons, WMO recognition of the com-\nparison as a regional one was withheld for a variety of reasons including the\ninability of the WMO working group on radiation to define acceptable protocol\nfor recognition in time for the comparison.\nTwo NWS stations have been added to the nine-station turbidity network in\na pilot program to provide turbidity data for the verification of direct\nradiation measurements at those stations\nARL\nFour pyranometers from the International Energy Agency round-robin test\nprogram were calibrated and tested over a 5-month period. The objective is to\ndescribe instrument characteristics to allow measurements to be corrected to an\nuncertainty of + 0.5% in the operating modes used in solar collector tests.\nRegular transfer calibrations of the working standard and control pyrano-\nmeters by the absolute cavity radiometer have verified a steady drop in sensi-\ntivity of about 0.5% to 1.0% per year in one type of pyranometer. This\nfinding emphasizes the need for regular and frequent recalibration of field\ninstruments.\n175","Plans FY 1985\nThe pyranometers and pyrheliometers returned during 1984 will be tested for\na year and then returned to the network. The long test period allows instru-\nments to be placed where the individual instrument characteristics are least\ndetrimental to the measurements.\nThe Sixth International Pyrheliometer Comparison (IPC) is scheduled for\n1985 in Davos, Switzerland. Participation in the IPC is the only recognized\nmethod for a Regional Center such as ours to acquire the World Radiometric\nReference scale, which is the basis for calibrations.\nAs many as 20 more NWS stations will be provided with sunphotometers and\nreduction tables to provide turbidity data for quality assurance of direct\nradiation data.\nAEROSOLS AND RADIATION\nAccomplishments FY 1984\nThe extremely large aerosol loading above Barrow, Alaska, observed in the\nGMCC optical depth data obtained during the Arctic Gas and Aerosol Sampling\nProgram (AGASP) in the spring of 1983, was determined to be due in part to\nstratospheric debris from El Chichon. The stratospheric, background tro-\npospheric, and transient tropospheric components were quantified and reported.\nThe results agree well with satellite measurements of stratospheric aerosol,\nwhich showed the maximum in El Chichon aerosol over Barrow occurring in\nMarch-April 1983.\nTotal radiation balance measurements were begun at the South Pole. This is\na new GMCC long-term monitoring project to gather information for heat budget\nstudies in the interior of the Antarctic.\nA fully automated solar radiation observatory was placed in operation at\nMauna Loa. The purpose of the solar measurements is to monitor radiative\nfeatures of total column aerosol, water vapor, and clouds. The facility con-\nsists of a medium-sized active solar-tracking spar capable of supporting\n200-300 pounds of instruments, a 32-channel analog voltage data acquisition\nsystem, and an automated observatory dome control. Several solar photometers\noperate continuously at the facility.\nDuring the AGASP flights near Barrow, Arctic haze events observed at the\nGMCC station showed large increases in aerosol backscatter coefficients\nand optical depth. In general, a main layer was located at about the 700-mb sp\nlevel; it was not associated with a region of high relative humidity; and it\nwas strongly correlated with surface-based measurements. The Arctic haze\nphenomenon appears to have its primary source in Eurasia with long-range\ntransport to Arctic regions in winter and spring.\nAn aerosol chemistry experiment at the South Pole showed that aerosol\nsulfur is correlated with concentrations of condensation nuclei (CN), having an\nannual cycle with a maximum in the austral summer and a minimum in winter.\n176","Aerosol sodium is correlated with o and shows a series of large events\nsp\nduring late austral winter. These data suggest that the sulfur is associated\nprimarily with the smaller-sized background aerosol particles and that the\nsodium is associated with sea salt transported to the interior of Antarctica\nby storms occurring during the austral winter.\nMeasurements of CN, o sp' and optical depth at Whiteface Mountain, N.Y., ,\nwere continued during 1984. Past data have shown that hazy episodes at\nWhiteface correlate strongly with high values of o and that these episodes\nsp\noccur when air mass trajectories are from the west and pass over the Great\nLakes industrial regions. Coincident optical depth and surface-based\nmeasurements can be used to estimate the vertical extent of the haze layer and\nthe total overburden.\nA light-weight, inexpensive balloon-borne sensor was developed for\nmeasuring cloud height and cloud thickness. Cloud presence is sensed by an\nincrease in horizontally scattered light, detected by a silicon photocell\nmounted within a light-diffuser glass bulb. The sensor couples to a regular\n1680-MHz radiosonde so that data telemetered to a ground receiving station\ninclude pressure, temperature, and humidity. Ten successful flights were made\nat Boulder. The cloud sensors may be useful for studying transport of water\nvapor into the stratosphere by very large cumulus clouds, or providing\nvalidation data for satellite measurements of cloud height and cloud thickness.\nPlans FY 1985\nPlans have been formulated for a GMCC project to maintain a continuously\nupdated data set on the aerosol state of the stratosphere. The data set\nwill be derived from the newly organized lidar network and limb-viewing\nsatellite observation system. The data will be used for correcting Umkehr\nobservations and for studies of mechanisms for climate change.\nAn aerosol experiment will be carried out at the Samoa GMCC observatory\nto measure the size distribution of sea salt and explain it in terms of\nmultiwavelength o measurements. Past measurements of o at Samoa show\na\nsp\nscattering function that increases with increasing wavelength, unlike measure-\nsp\nments at other sites which usually show decreasing scattering with increasing\nwavelength.\nGMCC will participate in a second AGASP experiment planned for the spring\nof 1985. Two important goals of this experiment will be the measurement of\nARL\naerosol chemistry profiles, especially aerosol sulfur, and the comprehensive\nmeasurement of aerosol optical extinction profiles. Attempts will be made to\ndirectly observe radiative-dynamical effects of the strongly absorbing Arctic\nhaze.\nTotal radiation balance measurements, similar to measurements made at the\nGMCC South Pole station, will begin at Barrow.\nAdvanced modern commercial sunphotometers will be acquired and deployed to\nobtain high quality information on the spectral characteristics of global\nbackground aerosol optical depth, and in support of the automated Dobson network\nfor developing an understanding of the effect of haze on the Umkehr measurement.\n177","OZONE\nAccomplishments FY 1984\nA classic set of Umkehr data obtained at Mauna Loa Observatory since 17\nMay 1982, following the eruption of El Chichon volcano in late March to\nearly April 1982, has illustrated dramatically the adverse effects of stra-\ntospheric aerosols on Umkehr observation. By early 1983 aerosol-induced\nerrors, which had originally exceeded 100% in some Umkehr layers, decreased to\nless than 20%. Stratospheric aerosol optical depths at Mauna Loa decreased\nfrom 0.27 to 0.05 during May to December 1982, and remained nearly constant in\n1983.\nLow total-ozone values were observed at Mauna Loa during August 1982\nthrough July 1983, compared with ozone amounts measured in 1981/1982 and\n1983/1984. Decreased ozone amounts were measured also at other Northern\nHemisphere stations. Partial destruction of ozone by El Chichon aerosols has\nbeen postulated as the cause of the ozone decrease. At Mauna Loa, the low\nozone values coincided with a minimum that occurred in January/February 1983\nin the quasi-biennial ozone oscillation and, therefore, are believed to have\nresulted primarily from stratospheric circulation changes that cause the\nquasi-biennial oscillations in ozone.\nProcessing of ozone data obtained during 1983 at Mauna Loa with ECC\nozonesondes was completed in FY 1984, yielding monthly, seasonal, and annual\nmeans as a function of altitude to 5 mb. The data are useful for validation\nof satellite-derived ozone profiles and as first-guess statistics for the\nreduction of Umkehr data. The sonde data showed markedly lower ozone amounts\nabove the ozone maximum in December 1982, compared with December 1983, due\nmost likely to stratospheric circulation differences over Mauna Loa during the\ntwo years.\nStandard Umkehr, Short Umkehr, and SBUV ozone profiles, observed con-\ncurrently over Boulder, were intercompared and found to agree best in layers 3-7\n(>90% correlation), but not as well in the lowermost and uppermost layers as\npredicted by theory. The comparison has partially revealed the nature of the\ndifferences that will require future investigative efforts to improve the\ncorrespondence between the ground-based Umkehr and satellite SBUV observational\nsystems.\nGMCC organized a global network of lidar stations to monitor the turbid\nstate of the stratosphere for applications to problems of climate and remote\nsensing (in particular, the Umkehr measurement). The network consists of three\nU.S., three European, two Japanese, one South American, and one Australian lidar\nstation. Data will be routinely archived and published at the World Ozone Data\nCenter, Toronto, and archived at NASA Langley Research Center. WMO has\nannounced its support for the network.\nA team of six scientists from GMCC, Universities of Chicago and Wisconsin,\nAtmospheric Environment Service (Canada), NESDIS, and NASA Goddard,\nstatistically examined the long-ter Umkehr data record from 13 stations for\ntrends, after correcting the record for volcanic stratospheric dust errors.\nIt was concluded that the corrected record shows a downward (-0.3% yr-1) trend\nin ozone concentration near 35-40 km. The magnitude of the trend is\n178","very close to the most recent theoretical photochemical prediction of a\nfluorocarbon-caused depletion. The long-term Mauna Loa transmission record\nwas used to quantify the magnitudes of stratospheric dust enhancements from\nvolcanic injections.\nWork that began in June of 1982 to automate seven Dobson spectrophotometers\nfor Umkehr observations was completed in FY 1984. Five of the seven instruments\nhave been installed at field stations, and are operational. The stations are\nBoulder, Colo. Haute Provence Observatory, France; Poker Flat, Alaska; Mauna\nLoa Observatory, Hawaii; and Perth, Australia. Calibrations in Boulder have\nindicated that Umkehr layer ozone amounts measured by each of the instruments\nagree on the average to within +5% of mean ozone amounts measured simultane-\nously with World Standard Dobson Spectrophotometer No. 83.\nTotal-ozone observations with Dobson spectrophotometers were continued at\nBismarck, N. Dak.; Caribou, Maine; Tutuila Island, Samoa; Mauna Loa, Hawaii;\nWallops Island, Va; Nashville, Tenn.; Boulder, Colo.; Tallahassee, Fla.; Fresno,\nCalif.; Huancayo Observatory, Peru; and Amundsen-Scott, Antarctica. First\ntotal-ozone measurements from the newly established Poker Flat, Alaska station\nwere received in March 1984.\nA long-period variation in total ozone is observed at Mauna Loa and other\nNorthern Hemisphere stations, with the ozone decrease rate at Mauna Loa being\nabout 3% per decade. Whether this decrease is due to ozone depletion by\nchlorofluorocarbons, or is the result of long-term variation in the strength of\nthe stratospheric circulation between equatorial and polar regions, is unknown.\nTests on high-altitude (to 40 km) ECC sondes were continued sporadically\nin Boulder during FY 1984. The performance of six instruments was compared\nwith that of other kinds of ozone-measuring devices (including UV photometers)\nin March 1984 aboard a balloon gondola flown to 41 km altitude from the\nNational Balloon Flight Facility in Palestine, Texas. Measurement precision\n(95% confidence interval level) exhibited by the instruments generally ranged\nbetween +2% and +10%, depending on altitude. Between 5 and 3 mb, the ECC\nsondes may have measured ozone amounts too low by 10%-20%.\nThe NOAA/GMCC Dobson Spectrophometer Central Laboratory in Boulder con-\ntinued to upgrade and calibrate Dobson instruments in the global total-ozone\nstation network. Work is under way to refurbish New Zealand Dobson instrument\nNo. 17 which was damaged by a flood in late 1983. In August, Australian\nDobson instrument No. 115 was optically aligned and calibrated, and training\nwas provided to Australian technicians to perform such work.\nARL\nPlans FY 1985\nIn an agreement with NESDIS, GMCC will conduct total-ozone, Umkehr, and\nozonesonde observations, beginning in January 1985, to obtain, process,\nevaluate, synthesize, and intercompare ozone data needed for validation of\nSBUV/2 satellite measurements of atmospheric ozone. Total-ozone and Umkehr\nobservations will be made at the five operational automated Dobson instrument\nstations, as well as at Huancayo, Peru, and Pretoria, South Africa. Total-ozone\ndata from an additional nine foreign cooperative stations will be used for vali-\ndation of the satellite observations. GMCC will conduct periodic calibration\n179","checks on the Dobson instruments at these stations. Ozonesonde observations\nare slated for three stations: Boulder, Colo. Mauna Loa, Hawaii; and Poker\nFlat, Alaska (or Edmonton, Canada). Weekly balloon instrument launches are\nplanned.\nWork to upgrade the Standard Umkehr and Short Umkehr inversion algorithms\nwill commence this year. Upgrading will consist of using new ozone absorption\ncoefficients and better a priori ozone statistics, and accounting for the\ntemperature dependence of ozone absorption. Included in the upgrading process\nwill be an attempt to improve the correspondence between the Umkehr and SBUV\nobserving systems.\nAutomated Dobson instruments for Umkehr observations will be installed at\nHuancayo and Pretoria early in 1985.\nAn intercomparison of Dobson ozone spectrophotometers will be held at\nMelbourne, Australia, in November/December 1984 under sponsorship of WMO and\nunder the direction of GMCC staff. Participating countries will be Australia,\nIndia, Japan, New Zealand, and the United States.\nA highly successful program established in 1981 to check on the calibration\nstatus of Dobson spectrophotometers in the global total-ozone station network by\nmeans of traveling, calibrated standard lamps will be repeated in 1985.\nCARBON DIOXIDE\nAccomplishments FY 1984\nThe concentration of atmospheric CO2 was measured continuously at Barrow,\nMauna Loa, Samoa, and the South Pole. A new instrument control and data\nacquisition system for the CO2 monitoring program was installed at Barrow, and\nthe field operations manual was revised to reflect changes in the operation of\nthe CO2 measuring system. In support of the continuous and flask CO2 analysis\nprograms, 168 reference gas tanks were calibrated for CO2 concentration\nThe continuous analyzer CO2 data for 1982 were made available to the\ncarbon cycle research community in the form of monthly means of the\nprovisionally selected background data set archived with the DOE Carbon\nDioxide Information Center (CDIC). In addition, provisional daily\nconcentrations for the four stations in 1982 were archived with WMO.\nThe full CO2 records from the four stations were corrected for systematic\nerrors (e.g., pressure broadening effect, analyzer non-linearity), edited for\ninstrumentally faulty data, and converted to the x81 mole fraction scale. An\nalgorithm for the selection of CO2 concentration data representative of\nbackground conditions was developed and applied to the Mauna Loa CO2 record\nfor 1973-1982. Selection of background data from the Barrow, Samoa, and South\nPole records began.\nThe CO2 flask sampling network continued to operate and now provides\nsamples from 24 stations including Christmas Island, in cooperation with\nScripps Institution of Oceanography (SIO), and Cape Grim, Tasmania, in\n180","cooperation with the Commonwealth Scientific and Industrial Research\nOrganization (CSIRO), Australia. More than 7,000 flask samples were analyzed\nfor CO2 concentration, providing a detailed record of the global variation of\natmospheric CO2 in space and time. The 1983 flask data were processed to\nfinal values, and a preliminary selection of background values was made. From\nthese data, the globally averaged CO2 concentration for 1983 was calculated to\nbe 342.4 ppm, representing an increase of 1.4 ppm over 1982.\nThe flask network CO2 concentration data for the period 1968-1982 were\narchived with DOE/CDIC and WMO. The selected flask data for this period were\nanalyzed for seasonal variation, latitudinal gradients, secular increase, and\nnatural and anthropogenic variations of these parameters. In particular the\nrelationsip between atmospheric CO2 concentration, gradients, and growth rate\nand the El Nino/Southern Oscillation phenomenon was studied. It was found\nthat a marked decrease in the CO2 growth rate preceded the minimum of the\nSouthern Oscillation Index and was followed by a period of higher than normal\nCO2 growth rates of 2-3 ppm yr-1.\nIn a cooperative program involving GMCC, CSIRO, and the Oregon Graduate\nCenter, more than 1,000 flasks from the CO2 flask network were analyzed by gas\nchromatography for CH4 (methane) concentration. A 1.5-yr record now exists of\nthe global distribution and variation of the atmospheric concentration of this\nclimatically important trace gas.\nFollowing laboratory testing and evaluation, field programs were\nundertaken using recently acquired gas chromatographs for the measurement of\nCO2 and CH4. On the joint Soviet-American Gases and Aerosols (SAGA)\nexpedition in the Pacific Ocean aboard the Soviet vessel Akademik Korolev,\ncontinuous measurements were made of atmospheric CO2 and CH4 and the partial\npressure of CO2 in surface ocean waters. The gas chromatography measurements\nagree well with those from simultaneously collected flasks and with the\ndistribution of atmospheric CO2 concentration derived from the flask network\ndata.\nA similar program was carried out during the CO2 Dynamics Study aboard\nthe NOAA ship Discoverer in cooperation with PMEL. On this cruise the partial\npressure of CH4 in the surface water was measured as well. On both cruises\nsignificant areas of undersaturation and supersaturation of CO2 in surface\nwaters were found. A gas chromatograph identical to that used on the cruises\nwas installed at the Mauna Loa Observatory to conduct a field comparison of the\ngas chromatographic and infrared techniques and to obtain a continuous record of\natmospheric CH4 at Mauna Loa.\nARL\nA comparison of the GMCC and SIO records of atmospheric CO2 concentration\nfor the period 1973-1984 at Mauna Loa was begun. In conjunction with this\ncomparison a field project was conducted to compare the GMCC and SIO analyzers\nat Mauna Loa, and an attempt was made to locate and quantify possible sources\nof discrepancy between the two systems.\nA data base consisting of meteorological information as reported on flask\nsample sheets for the period 1979-83 was created. These data were used in\nselecting the background data from the 1983 flask data set.\n181","The variability of atmospheric CO2 concentration at Barrow during the\nwinter of 1979-1980 was studied. It was found that periods of high CO2 con-\ncentration were correlated with high concentrations of anthropogenic aerosols.\nA study of air mass trajectories indicated Eurasian sources for these polluted\nair masses.\nPlans FY 1985\nMonitoring of the atmospheric CO2 concentration at Barrow, Mauna Loa,\nSamoa, and the South Pole will continue. New instrument control and data\nacquisition systems will be installed at the Mauna Loa, Samoa, and South Pole\nstations. Provisional daily means for the four stations during 1983 will be\narchived with WMO. The selection of background data from the full continuous\nanalyzer data sets through 1982 will be completed.\nAir samples for CO2 analysis will be collected at the 24 sites of the CO2\nflask sampling network. The possibility of replacing the site at Cape\nMearnes, Ore., with a site on the Olympic Peninsula, Wash., more suited to\nbackground measurements will be investigated. The 1983 flask data will be\narchived with the DOE/CDIC and WMO. The representativeness of the flask\nnetwork will be evaluated using flask sample data obtained on several cruises\nduring 1982 and 1983. A report will be prepared describing in detail the\nlocal geography and conditions at the flask sampling sites.\nThe measurements of CH4 in flask air samples from the network by gas\nchromatography will continue. The results from the first year of measurements\nwill be reported. The CH4 analysis system will be streamlined by automating\nthe data acquisition system, and upgraded through the purchase of a new gas\nchromatograph to replace an older instrument currently on loan from the Oregon\nGraduate Center.\nThe comparison of the NOAA and SIO records of CO2 at Mauna Loa for\n1973-1984 will continue. The NOAA record from Mauna Loa will be studied using\nthe time series analysis software package entitled \"SABLE\".\nThe measurement of CO2 and CH4 by gas chromatography at Mauna Loa will\ncontinue. The results will be compared with those obtained by the infrared\nanalyzer system. Gas chromatographic measurements of atmospheric CO2 CH4,\npCO2 and pCH4 in surface waters will be made aboard the NOAA ship Discoverer\nin cooperation with the CO2 Dynamics Study of PMEL.\nAn international intercomparison of CO2 measurements by several labora-\ntories will be initiated by GMCC under WMO sponsorship. This program consists\nof circulating a tank filled with a CO2-in-air standard gas among\nparticipating laboratories for analysis. The analysis results will be sent to\nWMO.\nThe variability of atmospheric CO2 at Samoa will be studied with respect\nto meteorological conditions and variations in other trace species.\n182","DATA ACQUISITION AND QUALITY CONTROL\nAccomplishments FY 1984\nNOAA staff completed the installation and acceptance testing of a 6-kW\nphotovoltaic power system at the GMCC station in American Samoa. The system\nwas purchased and installed with funds provided by the DOE Federal\nPhotovoltaic Utilization Program. The photovoltaic power system and\nassociated batteries supply approximately 0.8 kW of uninterrupted power to\nsensitive scientific equipment at the station. Since continuous operation\nbegan in February 1984, the system has operated without failure.\nTesting of an instrumentation control and monitoring system (CAMS) to be\nused at the GMCC observatories was completed and installed at the Barrow and\nSamoa stations. The CAMS is a compact, microcomputer-controlled system using\nthe Z-80 STD BUSS to interface memory, input-output ports, and monitoring\nelectronics. The peripherals include a cartridge tape recorder, a push-button\npad and display, and a printer. The system acquires data in both analog and\ndigital form and controls the operation of relays to provide calibrations to the\ninfrared analyzer measuring carbon dioxide. Using the display and printer pro-\nvided with CAMS, staff at the GMCC stations will be able to tabulate and\nmonitor the quality of data in real time. In addition, CAMS displays a series\nof flags to indicate major discrepancies in the observations.\nPlans FY 1985\nIn addition to monitoring and documenting the performance efficiency of\nthe new power system in Samoa, we plan to test alternative methods of battery-\ncharge maintenance to obtain more efficient charging on sunny days. If any of\nthese methods are successful, it is planned to increase the load to capacity\n1.0 kW.\nCAMS units will be installed at the Mauna Loa and South Pole\nobservatories early in FY 1985. Work will continue on streamlining the\nroutine station data processing in GMCC.\nA new GMCC program will operate and maintain instrumentation to\nacquire, process, and evaluate data needed for validation of satellite ozone\ndata in an agreement with NESDIS.\nARL\nGMCC will acquire Dobson data at 16 sites, 7 of which will be equipped\nwith automated Dobson instruments providing Umkehr observations. In addition,\nGMCC will maintain, calibrate, and repair as necessary the instruments at the\nautomated Dobson stations.\nGMCC will make ozonesonde flights and acquire ozone profile data at three\nsites in order to compare ozone profiles with SBUV/2 measurements.\nGMCC will oversee the acquisition of lidar data from sites already making\nlidar measurements (includes Mauna Loa Observatory and WPL lidar measurements\nat\nBoulder) in order to assess the stratospheric aerosol correction to SBUV/2, and\nUmkehr ozone measurements.\n183","GMCC will obtain, process, tabulate, synthesize, and intercompare data sets\nof Dobson-derived total ozone, Umkehr ozone profiles, ECC sonde ozone profiles,\nand lidar-derived aerosol profiles to help analyze SBUV/2 measurements of\natmospheric ozone.\nDevelopment work will be conducted on ECC ozonesondes to optimize the\ninstruments for the measurement of tropospheric ozone, and to reduce the cost of\nthe instruments.\nTRACE GASES\nAccomplishments FY 1984\nWeekly atmospheric baseline measurements of chlorofluorocarbons (CFC-11,\nCFC-12) and N20 continued at Point Barrow, Alaska; Niwot Ridge, Colo.; Mauna\nLoa Observatory, Hawaii; and Tutuila Island, American Samoa. Biweekly\nmeasurements have been made at South Pole with a newly installed gas\nchromatograph.\nA fully automated gas chromatograph and data system for the measurement of\nthe radiatively important species CFC-11, CFC-12, CC14, CH3CC13, and N20 was\nconfigured and tested at the Boulder laboratory.\nMonthly stratospheric balloon-borne water vapor soundings were made from\nBoulder, using frost-point hygrometers. With soundings for more than 3 years,\na climatology of the seasonal behavior of water vapor in the stratosphere over\nBoulder has been delineated. Two successful balloon intercomparisons were\nobtained between frost-point hygrometer instruments and several other types of\nstratospheric water vapor sounding instruments. This work confirmed a result\nobtained in 1983, which showed that frost-point hygrometers yield stratospheric\nwater vapor concentrations lower than does the Lyman-alpha instrument of the\nAeronomy Laboratory by about 0.7 ppmv at 4 ppmv.\nWith surface ozone measurements at the four GMCC baseline observatories now\nextending for up to 10 years, it is possible to look for long-term changes in\nthe\ntropospheric ozone content of the atmosphere. At Mauna Loa, where recent\nozonesonde profiles have confirmed the validity of the surface measurements as\nrepresentative of mid-tropospheric ozone behavior, an upward trend in the ozone\ncontent at about 700 mb seems to be emerging. Although this trend cannot yet\nbe judged statistically significant at the 95% confidence interval level, the\nresults in the next several years will need to be carefully watched.\nPlans FY 1985\nAtmospheric baseline measurements of N20 and chlorofluorocarbons will be\ncontinued at the GMCC observatories and Niwot Ridge.\nNew gas chromatographs will be purchased and automated for in situ\nmeasurements at the GMCC baseline stations of CFC-11, CFC-12, N20, CC14, and\n184","CH3CC13. Feasibility studies will be conducted for the measurement of other\nradiatively important halocarbon species such as CFC-22 and CFC - 13.\nA gas chromatograph for analyses of air samples for CH4 and CO will be\npurchased to build on the GMCC, CSIRO, and the Oregon Graduate Center coopera-\ntive program. Tests will be conducted to assess the suitability of the\nequipment for use in global CO monitoring.\nThe measurement of CH4 in flask air samples from the network by gas\nchromatography will continue. The results from the first year of measurements\nwill be reported. The CH4 analysis system will be streamlined by automating\nthe data acquisition system, and upgraded through the purchase of a new gas\nchromatograph to replace an older instrument currently on loan from the Oregon\nGraduate Center.\nThe important time series of stratospheric water vapor soundings in Boulder\nwill be continued with monthly balloon flights. In addition, as part of the\nsatellite-borne Stratospheric Aerosol and Gas Experiment (SAGE II), , water vapor\nand ozone will be measured at four locations from Alaska to Brazil. In order to\nestablish the reasons for the offset between the frost-point and Lyman-alpha\ninstruments, work will begin, to establish a laboratory methodology for com-\nparing these as well as other instruments used in measuring stratospheric\nwater vapor.\nContinuous monitoring of the ozone content near the surface will continue\nat the four GMCC observatories. The resumption of regular ozonesonde flights\nin Hawaii will allow further evaluation of the time series of surface\nmeasurements at Mauna Loa.\nARL\n185","","AERONOMYLABORATORY\nEldon E. Ferguson\nBoulder, Colorado\nDirector\nDirector\nO/P\nDep. Director\nESG\nCooperative\nCRP WRP PROFS WMP\nInstitutes\nAOML\nPMEL\nGLERL\nGFDL\nNSSL\nWPL\nARL\nAL\nSEL\nThe Aeronomy Laboratory conducts research on chemical and physical pro-\ncesses of the Earth's atmosphere to advance the capability to monitor, pre-\ndict, and control the quality of the atmosphere. The research concentrates on\nthe stratosphere and troposphere but also involves the ionosphere.\nResearch methods involve both in-situ and remote measurement of critical\natmospheric parameters, including chemical composition and dynamic properties\nsuch as wind velocities, turbulence, and wave motions. Theoretical programs\nin atmospheric photochemical modeling and in atmospheric dynamics and trans-\nport support the observation programs. An experimental laboratory chemical\nkinetics program supports the theoretical photochemical modeling program and\nalso supplies input for the development of new atmospheric monitoring and\nmeasurement technology.\nThe research of the Laboratory is accomplished by six interactive pro-\ngrams: Atmospheric Chemical Kinetics, Atmospheric Dynamics, Atmospheric Sam-\npling, Atmospheric Wave and Turbulence Theory, Optical Aeronomy, and Theoret-\nical Aeronomy.\nThe major focus of research is Air Quality; climate studies are also in-\nAL\ncluded in the Atmospheric Dynamics Program.\nATMOSPHERIC SAMPLING\nThe origins of the present Atmospheric Sampling program lie in the recog-\nnition that human activities may inadvertently pose a threat to the Earth's\nstratospheric ozone layer, which serves as a shield against harmful solar\nradiation. The Atmospheric Sampling Group was formed to address this critical\nproblem. Research efforts of the group led to the first successful\n187","measurements of chlorofluoromethanes at the altitudes in the stratosphere where\nthese compounds are significantly photodissociated into reactive chlorine\nspecies. The findings supported the predictions from theoretical models con-\ncerning the photochemistry of these compounds and, hence, the predictions of\nthe potential adverse consequences to stratospheric ozone. Since that time,\nthe scientific efforts of the group have followed the approach used in these\nstratospheric chlorofluoromethane measurements. That is, problems are\nselected that combine significant new scientific research with important na-\ntional or global atmospheric environmental questions. The instruments and\ntechniques required in the studies are generally conceived, designed, and\ndeveloped within the group and are subjected to rigorous laboratory and field\nvalidations. The subsequent field application of these instruments and tech-\nniques employs a variety of platforms : balloons, stratospheric and tropo-\nspheric aircraft, ships, vans, and semipermanent ground stations.\nThe experience, skills, and interests of the group have expanded consider-\nably since the initial stratospheric chlorofluoromethane studies and now en-\ncompass a broad range of topics in atmospheric chemistry and dynamics, which\ninclude the following:\nThe natural emissions that contribute to atmospheric acidity and\nalkalinity.\nThe transport, transformation, and deposition processes involved in\nacid deposition.\nThe tropospheric/stratospheric exchange processes that are a factor\nin regulating stratospheric and tropospheric chemistry and climate.\nThe tropospheric and stratospheric photochemical cycles responsible\nfor the production and destruction of global ozone.\nRelative to potential inadvertent deleterious alterations of the Earth's atmos-\nphere, several key environmental issues are being addressed: stratospheric\nozone depletion, acid deposition, tropospheric ozone production, and climate\nalteration.\nAccomplishments FY 1984\nDuring the summer of 1984, the abundance of the sum of all of the reactive\nnitrogen species, NO at a tropospheric site was determined for the first\ntime. The reactive nitrogen species play important roles in tropospheric chem-\nistry and climate, and the capability to detect their overall abundance opens\nup attractive prospects for determining global budgets of this key chemical\nfamily. The measurement site was located near Niwot Ridge, Colo., at an alti-\ntude of 3,000 m. NO was detected with a new technique developed recently in\nthe Laboratory for that purpose. It uses the reduction of these reactive\nnitrogen compounds by carbon monoxide, CO, at a heated gold catalyst to yield\nNO, which is then detected by the Laboratory's sensitive chemiluminescence\ndetectors. The air quality at the site varied from clean to moderately pol-\nluted, owing to transport of air from the Denver metropolitan area; thus the\nNO chemistry could be examined over a range of conditions. Correlations\n188","involving NO with other species measured at the same time demonstrated the\nbasic relations of the chemistry and transport, such as the age of the air\nmass and the role of the nocturnal boundary layer, in determining the produc-\ntion and deposition of NO\ny\nIn addition to the sum of the reactive nitrogen species, the summer inves-\ntigation at Niwot Ridge also included separate measurements of a number of the\nreactive nitrogen species, many measured in concert for the first time.\nKnowing both the sum of the reactive nitrogen species and many of the indivi-\ndual components provided new insight into the partitioning among the members\nof this chemical family. Nitric oxide (NO), nitrogen dioxide (NO), and ni-\ntric acid (HNO 3 were measured by the Laboratory's instruments, and\nperoxyacetyl nitrate, PAN, concentrations were determined by SRI International\nand the National Center for Atmospheric Research. It was observed that these\nfour species constitute a large fraction of NO but not 100%, indicating that\nadditional reactive nitrogen species are significant. PAN proved to be com-\nparable with NO and NO an important fact established here for the first time.\nDiurnal and seasonal behavior of the ratios showed the photochemical behavior\npredicted for the formation and loss of HNO 3 For example, nitric acid and\nNO (NO + NO) have been measured now at all times of day during all seasons.\nThe ratio of HNO to NO concentrations is observed to rise during the day and\nto decrease at night. For each season, this diurnal pattern can be well fit\nby modeling the production of HNO 3 from NO2 by combination with hydroxyl radi-\ncals and the heterogeneous removal of HNO3. The conclusion is that HNO 3 has a\nvery short lifetime in the troposphere (~12 hours in summer and ~24 hours in\nwinter) and that surface deposition is the primary removal process.\nAccurate assessment of the contribution of sulfur-bearing species to acid\nrain in \"clean\" continental air requires measurement below 0.1 parts per bil-\nlion by volume (ppbv) in locations where local anthropogenic contributions are\nusually absent and clearly recognizable. Measurements of surface tropospheric\nmixing ratios of sulfur dioxide, SO2, have been carried out as part of the\nmeasurements at Niwot Ridge. The investigation was conducted using an auto-\nmated portable gas chromatograph with a detection limit of about 10 parts per\ntrillion by volume (pptv). Strong correlations of SO2 mixing ratio with pre-\nvailing wind direction have been observed. Westerly winds frequently result\nin SO2 mixing ratios below 10 pptv. Easterly \"upslope\" air movement bringing\nurban air masses from the Denver metropolitan area show SO2 mixing ratios >1\nppbv. Positive correlation of SO2 with gas phase HNO 3 bespeaks a common\nsource and has implications for acid rain on the eastern slope of the Rocky\nMountains. Weak correlation with particulate sulfate indicates differing\nsources, a slow interconversion rate, or mediating factors not always present.\nFormate and acetate as well as other organic and inorganic anions have\nAL\nbeen measured in precipitation collected at Niwot Ridge (a remote site) and\nBoulder (an urban site). The organic anion concentration is usually at least\n20% of the nitrate concentration and occasionally is equal to the nitrate.\nFormate is the dominant organic anion measured; concentrations as large as 9 X\n10 5 molar occur in summer rain showers. Various dicarboxylic anions are ob-\nserved also, but their concentrations are generally much lower than formate's.\nThe total ion concentration is usually less at Niwot Ridge than at Boulder.\nHowever, ionic balance often leads to a somewhat lower pH at Niwot Ridge.\nOrganic acids have been observed in precipitation previously in remote oceanic\nareas. The present observations show that they can be significant\ncontributions to the acidity in urban and rural continental areas.\n189","In situ measurements of nitric oxide (NO, fall 1983 and spring 1984) and\nnitrogen dioxide (NO, spring 1984) were made during aircraft flights at alti-\ntudes ranging from 500 to 33,000 ft over the Pacific Ocean. These studies\nwere in collaboration with the National Center for Atmospheric Research (NCAR)\nand were conducted with an aircraft of the National Aeronautics and Space\nAdministration (NASA) During the fall series of flights, NO values in the\nmarine boundary layer and the free troposphere were observed to be extremely\nlow, with values ranging from 0 to 10 and 0 to 50 pptv, respectively. Alti-\ntude profiles within a single clean-air mass were constructed from measure-\nments made during constant-altitude flight legs, and a positive gradient with\naltitude was typically observed for NO. A strong positive correlation between\nNO (NO + NO) and ozone (03) was observed during the spring series of flights.\nTypical free tropospheric NO values ranged from 10 to 100 pptv, with NO/NO\nX\nratios exceeding by an average factor of 2.5 those that would be expected\nduring conditions of photochemical steady state. During the fall flights,\nelevated NO values were observed in the free troposphere during periods of\nsubsiding stratospheric air, and evidence for the production of NO in electri-\ncally active clouds was also observed. This investigation has provided the\nmost extensive look thus far at the budget and chemistry of NO and NO2 in the\nremote global troposphere.\nThe Laboratory participated in the second and last of the balloon flights\nconducted to intercompare the results of stratospheric water vapor instru-\nments, sponsored by NASA. These intercomparisons demonstrated that strato-\nspheric water vapor can be measured with an accuracy of about +25%. The most\nconsistent results were obtained by the Lyman-alpha detector of this Laboratory\nand the frostpoint instrument of the Geophysical Monitoring for Climatic Change\nDivision ARL. The difference, about 10% to 15%, was the same throughout all\nthe flights. This consistency affords the opportunity to discover the cause\nof the difference, thereby allowing a homogeneous data set from these two in-\nstruments, which are the only two making regular stratospheric water vapor\nmeasurements.\nThe Laboratory also participated in the third and last balloon flight of\nthe campaign sponsored by NASA. The goal was to obtain insight into how well\nstratospheric ozone can be measured with current instruments. Although many\nof the data are still being examined and compared, the initial results demon-\nstrate that it is formidably difficult to measure ozone reliably at 40 km,\nwhere good data are critically needed to evaluate the potential alteration of\nthe ozone layer by human activities. The Laboratory had two ultraviolet dual-\nbeam ozone photometers on the last balloon flight and configured the pair such\nthat tests could be made of the main sources of ozone measurement uncertainty.\nThese data show that losses of ozone to the walls of inlet lines and to the\nballoon itself are major sources of error. Such information will substan-\ntially shape the strategies being formulated as to how to conduct strato-\nspheric ozone monitoring over the coming decades.\nThe Laboratory's Lyman-alpha detector for water vapor was flown on board\nNASA's U-2 research aircraft in the spring of 1984. The goal was to examine\nthe structure of a tropopause fold with fast-response instruments measuring\nstratospheric and tropospheric trace species. The data elucidate the exchange\nprocesses induced by the folding event. The negative correlations between\nwater vapor and temperature, which are opposite to those expected in\nstratospheric air, suggest that these air parcels originated from near the\n190","tropical tropopause. Since the folding event was at middle latitudes, this\nmay be evidence of rapid long-range transport. This flight series was the\nfirst in NASA's Stratospheric Tropospheric Exchange Program, in which the\nAeronomy Laboratory will be involved.\nPlans FY 1985\nThe studies of nitrogen chemistry that were conducted at Niwot Ridge in\nthe summer of 1984 will be conducted again in the fall or winter. This should\nprovide considerable insight into the seasonal differences of NO and its com-\nponents and the chemistry and transport that introduce such differences.\nThe tungstic acid denuder tube will be tested as a viable method for the\nmeasurement of nitric acid and ammonia. Tests will be conducted at Niwot\nRidge, and comparisons will be made with the measurements of the filter-\ncollection technique.\nThe NO technique will be added to the airborne NO and NO2 instruments\nand used, in collaboration with NCAR, on a series of aircraft flights in the\nlate summer of 1985. NASA's aircraft will carry a suite of instruments that\nwill focus on the reactive nitrogen chemistry of the troposphere: the distribu-\ntions, reactions, and instrument reliability.\nA newly instrumented research van will be used to explore two aspects of\nthe tropospheric nitrogen species. First, in California, the constituents of\nPacific air masses will be examined. This measurement series will provide the\nopportunity to test the models of the chemistry of maritime air, a system in\nwhich a few fundamental processes are thought to be dominant. Second, the\nresearch van will make the first direct study of reactive nitrogen species\nemitted from the soil, which are thought to be one of the major natural\nsources that lead to nitrate in precipitation.\nIn conjunction with these nitrogen studies, a newly developed gas-\nchromatographic apparatus will measure the emissions of natural sulfur com-\npounds from the soils. Two University groups will be making simultaneous\nstudies, so that the comparison will provide insight into the reliability of\nsuch measurements. Calibration standards will have been intercompared earlier.\nThese nitrogen and sulfur studies will be conducted in the southeastern United\nStates, where such emissions are thought to be the largest.\nA state-of-the-art diode-array spectrometer was incorporated into a\nspectrometer/computer absorption spectroscopy apparatus. The device has\nbeen used to obtain spectra of stratospheric NO2 of heretofore unobtain-\nAL\nable quality. A key part of the procedure is a least-squares data reduction\nprocedure that employs standard spectral relative intensities obtained from\nlaboratory measurements. The system obtained total-column NO data when it\naccompanied the stratospheric NO/NO2 experiment into the field. Now the\nsystem is at Fritz Peak Observatory, Colo., and will use long-path (approxi-\nmately 10 km) absorption techniques to examine the photochemistry of several\ntropospheric species. The initial measurements suggest a role of aerosols in\nthe removal of NO3, and these studies will be expanded.\n191","The differential absorption lidar technique will be explored as a means\nfor measuring ozone in the free troposphere. There is currently no fully\nacceptable method to do such, despite the need to assess potential human al-\nteration of this important climatic and chemical species.\nThe test flights will be conducted for the new instruments that will take\npart in the Stratospheric Tropospheric Exchange Program. The aircraft will be\nthe ER-2, and the flights will test the Laboratory's instruments for measuring\nwater vapor, water vapor and ice, and ozone. These species are tropospheric\nand stratospheric tracers. The Laboratory will later add NO , a stratospheric\ntracer, to the set. The first experiment will address small scale exchange\nprocesses in the vicinity of jet streams. It is planned to concentrate on the\nlower side of the jet stream where flow of tropospheric mass into the\nstratosphere has been postulated to occur.\nATMOSPHERIC WAVES AND TURBULENCE THEORY\nThis program is devoted to theoretical studies of turbulence, waves, and\neddy transport in the atmosphere. These phenomena are basic to many areas\nof\ngeophysics, including meteorology, climatology, pollution dispersal,\noceanography, space physics, and aeronomy.\nWave and turbulence fluctuations are present in vast regions of the\natmosphere because the natural state of the atmosphere is often locally un-\nstable. Such fluctuations have a striking effect on transport of pollutants\nand were intensively observed as long as two decades ago. However, because of\nmathematical and conceptual difficulties, no theories of turbulence and\nnonlinear wave interactions were available for determining the strength of\nthese fluctuations and how they influence pollution dispersal and meteorology.\nThe development of such theories has become a principal concern of this\nprogram during the past decade.\nAccomplishments FY 1984\nThe Atmospheric Waves and Turbulence program (1) proved that gravity\nwaves \"break\" in a manner resembling the surfing of ocean waves, and that\nthis \"breaking\" is the principal process by which waves cause transport in\nthe atmosphere; (2) determined the buoyancy subrange spectrum of temperature\nfluctuations in atmosphere and oceans, and corrected a commonly quoted 20-\nyear old error in the literature concerning such spectra; (3) proved that\n\"return to isotropy\" the principal hypothesis of turbulence models--is\ninvalid, and developed a theory to determine realistic deviations from\nisotropy; (4) theoretically determined how observed height variations of\ngravity wave amplitudes can be used to infer eddy diffusivities in the\nmiddle atmosphere; (5) predicted that gravity waves cause diffusion to be\nanisotropic (with horizontal diffusivities greatly exceeding vertical dif-\nfusivities); (6) explained why vertically towed grid turbulence experiments\ndiffer from horizontally towed experiments, and how each is related to\natmospheric turbulence phenomena; (7) discovered a new mechanism by which\ngravity waves generate thin layers of turbulence as ubiquitously observed in\noceans and atmospheres, namely, a dynamical instability caused by nonlinearly\n192","steepened wave shear. This mechanism might provide the widely sought \"sink\"\nof fluctuation energy in oceans.\nPlans FY 1985\nThe following studies of turbulence in the atmosphere are planned:\nContinue to develop a reliable turbulence model of the planetary boundary\nlayer by applying contemporary turbulence theory from first principles.\nThis year's goal is to calculate the pressure-velocity correlations under\nstable as well as neutral stratified conditions.\nApply MST radar data to determine the seasonal variation of diffusivity\nin the mesosphere.\nExplain theoretically, and calculate, the apparently universal spectrum\nobserved for vertical scales of fluctuations in oceans and the atmos-\nphere.\nDevelop a theory for temperature fluctuations in oceans and atmosphere.\nApply theory to the boundary layer model currently used by the Naval\nEnvironmental Prediction Research Facility (NEPRF) The NEPRF facilities\nwill be used to test and expand the theory. A liaison has been set up\nwith NEPRF for this purpose.\nPlanned studies of gravity waves include a theoretical investigation of\nthe spectral distribution, and harmonics, of atmospheric gravity waves; an\nattempt to determine the \"sink\" of gravity wave energy in oceans and atmos-\nphere; continuation of the modeling of diffusion and friction from 20- to 100-\nkm altitude, the dynamical coupling of the troposphere to the mesosphere, the\ninfluence of gravity waves on the mean flow, the role of tidal waves in atmos-\npheric diffusion, and the interaction of gravity waves with airglow and minor\natmospheric constituents. Recent new insights into the importance of gravity\nwave heat flux and Rayleigh friction in the middle atmosphere will be developed\nfurther. In addition, a study will be initiated of planetary wave \"breakup\"\nin the stratosphere.\nTHEORETICAL AERONOMY\nThe objective of the Theoretical Aeronomy Program is to undertake theore-\nAL\ntical studies of important atmospheric problems, to construct and utilize com-\nputer models of the chemistry and dynamics of the atmosphere, and to analyze\natmospheric data collected within the Laboratory or by collaborative experi-\nments. The ultimate goal of the program is to attain an understanding of the\ncomposition, dynamics, and energy budget of the atmosphere that is sufficiently\ndetailed to permit accurate predictions of trends. In recent years the prin-\ncipal concern has been with problems related to the minor-constituent compo-\nsition of the stratosphere and mesosphere (the middle atmosphere), deriving\nlargely from the widespread practical concern with stratospheric ozone and its\n193","potential depletion by artificial pollutants. More recently, however, the\nactivities of the group have expanded to investigate problems of tropospheric\nchemistry and tropical atmospheric dynamics. These newer areas are expected\nto grow, in parallel with corresponding growth and shifts of emphasis in the\nexperimental programs of the Laboratory. Most of the program's projects are\ndeveloped and carried out in close collaboration with the Laboratory's experi-\nmental programs, or with other atmospheric research groups outside the\nLaboratory, including at present those at GFDL, NCAR, and the University of\nColorado. These outside links are essential to the objectives of the program,\nand will be maintained and strengthened where possible in future years.\nIn addition to its own projects, the group has the important function of\nassisting other Laboratory programs on problems that require advanced computer\nprogramming techniques. This direct service function provides further coupling\nbetween this program and the more experimental side of the Laboratory.\nAccomplishments FY 1984\nTROPOSPHERE\nResearch in tropospheric photochemistry centers around acid deposition\nand tropospheric ozone. Acid deposition is a serious problem in the north-\neastern United States and eastern Canada. Precipitation with pH in the\nrange of 4.0 to 4.5 is quite common in these areas downwind of midwestern\nindustry. Most of the anions contributing to the high acidity are SO4 and\nNO3, the precursors of which are SO2 and NO (NO + NO 2 Tropospheric ozone\nplays a central role in the photochemistry that controls the abundance and\ninteraction of SO2, NO , and other important atmospheric trace gases (e.g.,\nCO, CH4, and H2S). The photochemistry and transport of acid material and\nozone are closely related. There is increasing evidence that tropospheric\nozone may have been perturbed by anthropogenic emissions of hydrocarbons and\nNO (NO + NO) Perturbation of tropospheric ozone may cause a chain reaction\nthat could change the distribution of trace gases. Since ozone and some of\nthe trace gases absorb infrared radiation in the window of CO2 and H20\nabsorption, the radiation budget in the troposphere, and thus the climate, may\nbe altered. In addition, surface ozone may damage plants and may be a health\nhazard.\nThe Theoretical Aeronomy Program is involved in several topics of\nresearch in the areas of tropospheric ozone and acid deposition:\nCollaboration with the Atmospheric Sampling Program on planning and\ninterpreting measurements of NO , O3, HNO 3 SO2, and particulate\nNO3\nand\nS04, with emphasis on measurements made at Niwot Ridge, Colo.\nCollaboration with scientists at GFDL on modeling the tropospheric ozone\nand NO distributions with a three-dimensional general circulation model.\nStudies of the detailed photochemistry of O3, NO x' OH, and hydrocarbons\nin a one-dimensional model.\nCollaboration with scientists at NCAR on developing a mesoscale air\nquality model for the Colorado Front Range.\n194","Development of a combined liquid-phase and gas-phase photochemical model\nto study the oxidation of NO and SO\nX\nModel studies of the distribution of NO and SO2 that are produced from\nX\nnatural sources.\nCollaboration with the Atmospheric Sampling Group has resulted in some\nvery important advances in the understanding of the atmospheric processes that\ninfluence tropospheric ozone and acid rain. By comparing model calculated values\nwith the ratios of HNO 3/NO and NO3/NO measured at Niwot Ridge, it is con-\ncluded that the lifetimes of HNO 3 and NO 3 are both shorter than 24 h in the\nplanetary boundary layer. In addition, the OH concentration calculated from\nthe model is probably a factor of 2 too high. The high sensitivity of the\nNO/NO detector and the extensive data on NO and 03 provide an opportunity to\ndeduce the background 03 level. Since NO is a precursor of 0 the\nbackground 03 level can be defined as the asymptotic value of 03 when the NO\nmixing ratio is less than 0.5 ppbv. This method provides an objective way to\ndetermine the background 03 level at a rural station by measuring 03 and NO\nsimultaneously. In addition, the seasonal variation of the 03 mixing ratio is\nfound to be strongly influenced by anthropogenic NO and hydrocarbon emissions\nX\nwhen the measurements of 03 are made in the afternoon. However, this is not\nthe case for 03 observed at night or in the morning because of low\nphotochemical ozone production. This finding will help the analysis of\nozonesonde data to evaluate the anthropogenic impact on the vertical\ndistribution of ozone in the industrialized regions.\nNitrate deposition over remote oceanic regions and in the pre-industrial\npolar ice cores has been studied in order to quantify the natural background\nbudget of NO NO3, and HNO 3 It is shown that the total nitrate deposition\nlies between X 108 and 20 X 10 8 molec s-1 which corresponds to\n2 to 8 Tg(N) yr-superscript(1).\nThe nitrate deposition in ice cores in the two polar regions is of parti-\ncular interest. Post-industrial values in Greenland are about a factor of 2\ngreater than the pre-1900 values, while there has been no detectable change in\nAntarctica. These data can be used to evaluate the long-range transport of\nnitrate. Seasonal variation in the polar ice core nitrate deposition shows a\nclear strong summer maximum. The nitrate deposition fluxes over remote\noceanic regions are not correlated with either 222 Rn or dust particles,\nindicating a non-continental NO source. It is concluded that the most likely\nX\nsource is NO produced by lightning in the upper troposphere. The total\nlightning source is estimated to be about 10 to 20 Tg(N)yr-1. On the basis\nof\nsatellite lightning frequency, the nitrate deposition flux due to lightning in\nNorth America can be estimated to be about 5% to 10% of the anthropogenic\nAL\nvalue.\nThe transport of tropospheric ozone has been investigated by a three-\ndimensional global circulation model simulation in a collaborative effort\nwith\nscientists at GFDL. The model assumes that ozone is transported from the\nstratosphere and deposited at the surface. Many of the observed spatial and\ntemporal variations of ozone have been successfully simulated by the model,\nincluding seasonal and latitudinal variations in both absolute concentration\nand relative changes. There are also many disagreements between modeled re-\nsults and observed values. Latitudinal distribution above 50°N indicates that\n195","there is a major defect in the model meridional transport. Continental sur-\nface ozone in the industrialized areas is too low, suggesting the need to in-\nclude photochemical production of ozone.\nDevelopment of the mesoscale air quality model has progressed as planned.\nA two-day mesoscale meterological model has been run for the case of July 26,\n1983. There was an upslope wind during the day and the Niwot Ridge station\nwas in full operation. The domain contains the whole western United States\nwith 60 X 60 km resolution, and finer resolution (20 X 20 km) for Colorado.\nTracer experiments have been run with a simple mass conservation scheme, with\nsatisfactory results.\nMIDDLE ATMOSPHERE\nChemical-dynamical studies of the middle atmosphere have continued, with\nan increased emphasis on the photochemistry and transport of ozone in both the\nstratosphere and mesosphere, and on the chemistry of stratospheric chlorine\ncompounds. These studies have been performed in collaboration with the\nNational Center for Atmospheric Research, using a two-dimensional residual\nEulerian model that extends from 16 to 116 km altitude, from pole to pole.\nThe advantage of the residual Eulerian framework can be briefly summarized as\nfollows: It can be shown that when the classical Eulerian mean and eddy trans-\nports are computed self-consistently, a large cancellation occurs such that\nthe remaining net transport in the stratosphere is a small residual. Problems\ncan arise in photochemical modeling because often neither of the two terms is\ncomputed at all; rather the eddy transports are parameterized by eddy diffusion\ncoefficients and the mean circulation is taken from a dynamical model study.\nThus the eddy coefficients may not be consistent with the adopted mean circu-\nlation, and the appropriate cancellation between the two may then not be\nachieved. Recent dynamical studies have shown that the cancellation problem\ncan be alleviated by using the residual Eulerian or diabatic circulations, which\nrepresent the desired net transport in the stratosphere without the need for\neddy-mean flow cancellation, provided that the eddies are approximately steady\nand conservative.\nA shortcoming of this approach, however, is the question of the role of\ntransient, dispersive eddies in the transport of chemical constituents.\nAlthough steady conservative eddies do not appear when the dynamical equations\nare cast in the residual Eulerian representation, some degree of eddy\ntransience/mixing must occur in the stratosphere. A great deal of recent work\nin the field has focused on the elucidation of the importance of these mixing\neffects. One approach to the problem is to examine the computed and observed\ndistributions of chemical tracers such as N20, CH4, CFC13, etc. N20 and CH4\nare particularly attractive as tracers because satellite data on their global\ndistributions have just become available. We have therefore added chlorine\nchemistry to our model and have compared results for the chlorofluorocarbons,\nN20, and CH4 with available data. We find that relatively small vertical and\nhorizontal mixing coefficients (about 3x10 9 cm² s-superscript(1) in the horizontal and\n1x103 cm² S -1 in the vertical) provide the best calculated distributions of\nthese diverse tracers, compared with the ensemble of observations.\nIn agreement with available satellite and in situ data, our model results\nindicate that a substantial latitude gradient in atmospheric methane occurs\n196","near 40 km, with tropical values that are about two to three times greater\nthan those obtained at middle latitudes. This is a result of upward transport\nfrom the methane-rich troposphere in the tropics, and downward, poleward\ntransport at higher latitudes, by the computed mean meridional circulation.\nThese spatial variations in methane influence the partitioning of chlorine\nbetween HC1 (an inert reservoir) and C10 (a free radical that catalytically\ndestroys ozone). Thus, the distribution of C10 depends in turn on the methane\ndistribution (particularly near 35-40 km), with associated effects upon the\nchlorine-catalyzed destruction of ozone. Further, observed local variability\nin methane at middle latitudes is consistent with much of the observed\nvariation in stratospheric C10 near 40 km. We have shown that spatial and\nshort-term temporal variability in methane has potentially important con-\nsequences for the HC1 and C10 distributions in the stratosphere, and their\nlocal variability, as well as for ozone densities.\nA particularly fruitful application of our two-dimensional dynamical\nchemical model has been in the interpretation of satellite data, both from the\nSolar Mesosphere Explorer (SME) satellite, and from the Limb Infrared Monitor\nof the Stratosphere (LIMS) experiment onboard Nimbus 7. The latter experiment\nrevealed the presence of extremely large mixing ratios of NO in the polar\nnight mesosphere, and a gradual accumulation of polar mesospheric NO\nthroughout the winter. We previously suggested that downward transport of\nthermospheric NO could lead to such an enhancement of NO at mesospheric and\nperhaps even stratospheric X levels. If the thermospheric NO could reach\nthe\nstratosphere, it might even influence stratospheric ozone abundances,\nproviding a mechanism for long-range thermosphere-stratosphere coupling.\nThe observations obtained by the LIMS experiment provide striking evidence of\ndownward transport of thermospheric NO to mesospheric levels, and suggest\nthat the upper stratosphere is also affected by downward transport poleward of\nabout 60° in winter. We have discussed and interpreted these satellite data\nin detail.\nCollaboration with the SME satellite team has continued. We have used\nthe observed distribution of NO2 to infer the N205 distribution in the\nstratosphere with the hope of providing theoretical information about N205 to\naid experimental efforts to detect it in the stratosphere. We have also\ncontinued our study of mesospheric ozone data from SME. A particularly\npuzzling aspect of the SME data was the observation of pronounced seasonal\noscillations near 80 km, with maxima at equinox that are about twice as large\nas the observed abundances at summer and winter solstice. Purely photo-\nchemical and temperature effects would tend to produce maxima at solstice, not\nequinox, so we were led to pursue a dynamical explanation for the observed\nfeatures. Recent work has suggested that breaking small-scale gravity waves\nplay an important role in the dynamics of the mesosphere. We have incorpo-\nAL\nrated a parameterization of the propagation and dissipation of gravity waves\ninto our dynamical-chemical model. This parameterization is used to compute\nboth the momentum forcing and turbulent diffusion induced by the waves at\nmesospheric altitudes, providing the needed transport parameters for the\nphotochemical constituents in the model. We find that the structure of the\nobserved equinox maximum in ozone near 80 km is consistent with our theoret-\nical results when the seasonal and latitudinal variations in turbulent\ndiffusion induced by such waves are considered. This work suggests that\nobservations of mesospheric ozone may have important applications in\nfurthering our understanding of mesospheric dynamics.\n197","ATMOSPHERIC DYNAMICS AND CLIMATE\nCollaborative studies with the Atmospheric Dynamics Program of the\nproperties and variability of the tropical tropopause have continued using the\nexisting data base of radiosonde measurements made at tropical stations over\nthe past 30 years or more. The principal results are as follows:\nThe correlation in the interannual variations of tropopause height at\ndifferent stations is excellent for stations within about 10° of the Equa-\ntor but falls off substantially between 10° and 20° latitude.\nThere is a significant correspondence between the height of the tropo-\npause and the phase of the quasi-biennial oscillation in the winds of the\ntropical lower stratosphere; the phase relationship is qualitatively\nconsistent with the existence of the vertical motions needed to maintain\ngeostrophic balance in the time-varying winds.\nThe height of the tropopause is positively correlated with the sea-\nsurface temperature anomalies of the eastern tropical Pacific Ocean and\nhence with the phase of the Southern Oscillation; in particular, tropical\ntropopauses tend to be high all over the world during El Nino years.\nInterannual variations in average tropical tropopause height are\npositively correlated with interannual variations in the total global\nangular momentum of the atmosphere; such a correlation could have been pre-\ndicted from current theories of the general circulation of the atmosphere\nand angular momentum transport, but had not been observed before.\nA pronounced periodicity of about 20 days has been found in the height of\nthe tropopause in the western Pacific at certain times of year; the same\nperiod appears to be present in the winds near the tropopause, and its re-\nlationship to the periodicities reported by others is under active inves-\ntigation.\nThe relationship between deep cumulus convection, tropopause height, and\ntroposphere-stratosphere exchange is being studied; it is hoped that this\nwill help to shed light on some basic aspects of atmospheric dynamics,\nand will lead to a sounder basis for estimating the response of the\nglobal atmosphere to such external influences as changes in solar\nradiation or changes in radiative heating brought about by changing\nconcentrations of carbon dioxide and other trace species.\nPlans FY 1985\nTROPOSPHERE\nTropospheric ozone and its possible perturbation by anthropogenic acti-\nvities will continue to be one of the major subjects of our research. Impor-\ntant problems in this area are the photochemical production and destruction\nof O 3, transport of 0 3 the distribution of tropospheric NO OH, and RO2\nradicals, and the effects of nonmethane hydrocarbons. We will continue to\nstudy these problems by working closely with the Atmospheric Sampling group\n198","and the Atmospheric Chemical Kinetics group. Collaboration with scientists\nat GFDL on three-dimensional modeling will be strengthened in both strato-\nspheric and tropospheric modeling.\nStudies of the acid deposition problem will be expanded. Emphasis will\nbe on atmospheric transformations of SO2 and NO , heterogeneous processes, and\nnatural emissions of sulfur and nitrogen compounds. Developing a regional\nacid deposition model for the Colorado Front Range is a long-range goal for\nthis group. The model will be very useful for interpreting the data at Niwot\nRidge and for designing other measurement strategies. It will consist of a\nmesoscale meteorological model and a photochemical model. It is clear that\nsuch a model can be readily applied to study regional oxidant problems such\nas that of rural 03. This model will be developed in collaboration with\nscientists at NCAR.\nMIDDLE ATMOSPHERE\nThe interaction of dynamics and chemistry in the middle atmosphere\nrepresents an important element in our understanding of aeronomy. We plan to\ncontinue to pursue our studies of the natural and perturbed stratosphere and\nmesosphere. We hope to concentrate on the effects of future chlorine pertur-\nbations on stratospheric ozone, and to begin to include a more detailed treat-\nment of infrared radiation in both the mesosphere and stratosphere. The latter\ngoal should eventually lead to a coupled radiative/dynamical/chemical model,\nand we anticipate that such studies will lead to a more detailed understanding\nof the middle atmosphere and its response to perturbations.\nATMOSPHERIC DYNAMICS AND CLIMATE\nThe study of the tropical tropopause region using radiosonde data will\ncontinue. Emphasis will be on (1) further development of the conceptual pic-\nture of troposphere-stratosphere interaction in the tropics, (2) a thorough\ninvestigation of the 20-day periodicity in tropopause heights and winds in the\nwestern tropical Pacific, and (3) a refined and more complete study of the\ncorrelation between tropopause height and global atmospheric angular momentum,\naimed at exploring the cause-and-effect relationship. The connection between\ntropopause properties and the wind fields of the tropical lower stratosphere\nand upper troposphere will be investigated.\nATMOSPHERIC DYNAMICS\nAL\nThe objective of the Atmospheric Dynamics program area is to further our\nunderstanding of the dynamics of the atmosphere below 100 km by taking\nadvantage of the unique experimental and analytical capabilities of the group.\nThe principle experimental technique of the program is called the MST (meso-\nsphere-stratosphere-troposphere) radar technique. Such radars are so\nsensitive that they obtain echoes from irregularities of density and humidity\nin the lower atmosphere, even in the absence of clouds, and from\nirregularities of electron density in the upper atmosphere. Radars that are\nsensitive enough to observe only in the lower stratosphere and the troposphere\n199","are called ST (stratosphere-troposphere) radars. Since these radars are phase\ncoherent, they measure the Doppler shift of the echoes, from which profiles of\nradial wind (including the vertical component when the antenna is pointed\nvertically), and profiles of certain parameters of turbulence are obtained.\nBecause of their rapid cadence of measurement (up to one profile per minute)\nthe MST radar technique is well suited for studying phenomena that vary\nrapidly in time, such as internal gravity waves and turbulence, but they are\nalso useful for studying slowly varying phenomena, such as tides and planetary\nwaves. Because of their great altitude range, they are particularly useful\nfor studying the vertical transport of energy and momentum through the\natmosphere in the wave fields. The program has followed several lines of\nexperimental research to exploit the capabilities of the MST radar technique.\nAt the present time the program has three radars in operation: the Poker Flat\nMST radar near Fairbanks, Alaska, the Sunset ST radar near Boulder, and the ST\nradar at Ponape in the Federated States of Micronesia. The Poker Flat and\nPonape radars operate continuously; the Sunset radar is operated for\ncampaigns.\nAccomplishments FY 1984\nAIR QUALITY\nOn several nights during 1983 simultaneous measurements of the turbulence\nstructure constant C 2 were made by the Sunset ST radar and by an optical\nn\nstellar scintillometer developed by the University of Nice, France. The\nprofiles for two nights in November 1983 agreed very well. Since these two\ninstruments were quite different and were independently calibrated, this\nagreement shows that both correctly measure C On two nights in June,\nhowever, the scintillometer C 2 was much smaller over a large altitude range.\nIf the explanation of this discrepancy turns out to be physical, rather than\ninstrumental, then it will have important implications for atmospheric\nturbulence.\nThis group was the first to obtain data from an array of ST radars. The\nmeasurements were made by three radars in a 5-km triangle in southern France\nduring April and May 1983 as part of the ALPEX (ALPine EXperiment) of the\nGlobal Atmospheric Research Program (GARP), in cooperation with the Laboratoire\nde Sondages Elcctromagnetiques de l'Environment Terrestre, Toulon, France.\nCross-spectral analysis of the data has resulted in the determination of the\nparameters of many gravity waves, with horizontal wavelengths from 7 to 40 km\nand phase speeds from 5 to 20 m s-1. This experiment demonstrates for the\nfirst time that arrays of ST radars can determine the properties of gravity\nwaves in the free atmosphere, which is difficult to do by any other technique.\nIn 1981 we studied the generation of gravity waves by thunderstorms,\nusing a single ST radar in Colorado. In 1983 these experiments were continued\nusing data from three radars and 20 microbarographs in Colorado. Many of the\ndata were provided by WPL and PROFS. Analysis continued in FY 1984 in\ncooperation with the Georgia Institute of Technology and the Istituto per la\nFisica dell' Atmosfera, Rome, Italy.\nWe have continued studies of mesoscale fluctuations of wind in the atmo-\nsphere, not only in order to describe their statistical properties but also to\n200","understand their physical nature, which is the subject of controversy. MST\nradar data have been analyzed to obtain the power spectra of the fluctuations as\na function of frequency and vertical wavenumber. Also, in order to obtain a\ncomplete picture of the fluctuations, data collected by NASA during the Global\nAir Sampling Program (GASP) have been analyzed to obtain power spectra as a\nfunction of horizontal wavenumber. The resulting spectra are remarkably univer-\nsal in both shape and amplitude, having a standard deviation of amplitude of\nonly a factor of 2.5.\nA study of the kinetic energy density of the atmosphere as a function of\nseason, height, and wave period has been undertaken using the 5-year data base\nfor Poker Flat. Preliminary results show that the atmospheric kinetic energy\ndensity for all wave periods decreases systematically with height.\nIn a related study, the transport of momentum in the atmosphere by\ngravity waves and tides has been measured using Poker Flat data. The results\ncompare with similar measurements at lower latitudes. Both the temporal and\nspectral variability of this quantity with height will be immediately useful\nin determining how momentum is distributed throughout the atmosphere by\natmospheric waves.\nThe mean vertical velocity plays an important role in the dynamics of\natmospheric circulation, particularly in the vertical transport of energy\n(including latent heat) and in the initiation of precipitation. We have shown\nthat mean vertical velocities measured by an ST radar on the Colorado Piedmont\nagree fairly well with mean vertical velocities inferred by analysis of radio-\nsonde balloon data when the wind is toward the Rocky Mountains. We have also\nshown that during a widespread rain event the occurrence and rate of precipi-\ntation was correlated with the ST radar mean vertical velocity.\nA major discrepancy has appeared between the mean vertical motions in the\nmesosphere observed at Poker Flat and the motions deduced from theoretical\nmodels. It is possible that this discrepancy arises from the different coordi-\nnate systems used for the radar observations (Eulerian) and current theoretical\nmodels (Lagrangian), as a result of the effect of intense gravity wave action in\nthe region. If substantiated, this discrepancy would bear heavily on future\ncomparisons between observations and theory.\nIn June 1983 we participated in the STATE (STructure and Atmospheric\nTurbulence Environment) program, a joint experiment using the Poker Flat MST\nradar and a series of experimental rockets from the Air Force Geophysical\nLaboratory. Preliminary analyses of the results show a very cold summer arctic\nmesopause and regions of intense turbulence that arise from the breakup of\nupward-propagating gravity waves.\nAL\nCLIMATE\nWe installed the first tropical ST radar at Ponape, Federated States of\nMicronesia. Vertical wind data that have been gathered continuously since\nearly May show a number of unique characteristics of the tropical atmosphere.\nIn particular, it appears that the radar echoes are enhanced during the typi-\ncally brief but intense rainstorms. Such an effect has not been observed at\nthese long wavelengths (6 m) in middle latitudes.\n201","Plans FY 1985\nAIR QUALITY\nThe generation of gravity waves by thunderstorms will be studied further\nby completing the analysis of the 1983 radar and microbarograph data.\nStudy of mesoscale fluctuations will continue by examining spectra of\natmospheric parameters (including both wind and temperature) from various\nsources and by comparing the power spectra with models based on the theories\nof gravity waves and two-dimensional turbulence. Comparison of models with\npower spectra from MST radar data taken looking simultaneously at the vertical\nand at a slant will be particularly critical. Analysis of the GASP data will\ncontinue in order to determine the climatology of mesoscale spectra as a\nfunction of latitude and underlying topography.\nThe preliminary study of kinetic energy density profiles will be\nexpanded by further, more detailed analyses. Initial calculations of rotary\nspectra will be done. The ratio of power in the clockwise to counterclockwise\nspectra is a measure of the ratio of downgoing to upgoing wave energy. A more\ndetailed study of the vertical flux of horizontal wave momentum will be\nundertaken at Poker Flat by using antenna beam switching to make measurements\nsymmetrically about the zenith, in addition to the present vertical/slant\nconfiguration. If fluxes measured by both configurations agree, then fluxes\ncan be determined from the entire 5-year data base at Poker Flat. In\ncombination with theoretical developments in the Atmospheric Waves and\nTurbulence program and elsewhere, these studies should lead to a greatly\nimproved understanding of wave energy and momentum transport and deposition in\nthe middle atmosphere.\nThe mean vertical velocity will continue to be studied by extensions\nof the methods described in Accomplishments FY 1984. However, before the cap-\nability of the MST radar technique can be fully assessed it will be essential\nto have a radar sited in flat terrain. For this reason we have proposed to\nNSF that we construct and operate a state-of-the-art ST radar near Urbana,\nIll. Although this \"Flatland\" radar was motivated by the need to measure\nvertical velocities, the absence of terrain effects will make the data uniquely\nvaluable for studying gravity waves and energy and momentum transport in the\nlower atmosphere. If funded, this radar will provide a major new direction\nfor the program.\nWe will continue our analysis of the STATE data base, in order to under-\nstand better the relationship between neutral turbulence, echo power, and\nwavebreaking processes in the mesosphere-lower thermosphere. This effort will\ninvolve collaboration with a number of scientists outside the Aeronomy\nLaboratory.\nPlans are also under way for a second series of rockets similar to STATE.\nThis program, directed by NASA Goddard Space Flight Center, is expected to\nstart during the winter of 1985. It will elucidate the reasons for the\nmarkedly different conditions in the summer and winter arctic mesosphere.\n202","CLIMATE\nThe second major new direction of the program is the study of the\ntropical atmosphere using ST radars.\nThe Ponape radar will be improved to include a beam-swinging capability\nso that the horizontal wind as well as the vertical wind can be measured.\nThese measurements should reveal the character of wind variability in the\noceanic tropics.\nThe relation between enhanced echoes and rainfall will be studied quanti-\ntatively in order to understand the nature of the enhancements and their\nrelation to convective cloud dynamics.\nThe program has been funded by NOAA's Office of Oceanic and Atmospheric\nResearch to establish three ST radars in the equatorial Pacific for a 10-year\nperiod as part of the international Tropical Oceans, Global Atmosphere (TOGA)\nprogram. Site surveys for two of the radars have been completed and two of the\nradars should be installed during FY 1985. The data from the TOGA and Ponape\nradars will be used by Aeronomy Laboratory and other scientists to study\nvertical motions in large cumulonimbus clouds, the vertical transport of minor\nconstituents, gravity waves and turbulence properties of the tropical\natmosphere, and equatorial (large-scale) waves, which are thought to be\nimportant in controlling climate variability in middle latitudes.\nOPTICAL AERONOMY\nThe Optical Aeronomy program uses optical measurements of the atmosphere\nas a tool for studying fundamental processes such as energy balance, com-\nposition, and dynamics. Major attention is now given to measurements bearing\non the composition and dynamics of the lower atmosphere, principally the\ntroposphere and stratosphere, although important problems in the upper\natmosphere still continue to receive some attention.\nAccomplishments FY 1984\nWe measured stratospheric NO 3 over a 5-year period ending in 1983 and\nfound its seasonal and latitudinal behavior to be in serious disagreement with\nthat predicted by chemical models. A rapid rise in abundance at the end of\nMarch and a gradual disappearance in summer were the outstanding features of\nAL\nthe disagreement. We have now discovered that the abundance of NO 3 is almost\nperfectly correlated with the previous location of stratospheric air; when the\nair has been at high latitude (>60°) the NO 3 content is low when the air\nreaches middle latitude. If the air has remained at middle latitude, then the\nNO abundance is not anomalously low. We speculate that an unknown process,\nexisting only at high latitude, creates in stratospheric air an unknown\nspecies capable of destroying NO 3 When the NO 3 abundance was low we formerly\ncould obtain only upper limits; with a new diode array spectrometer we now\nhave obtained a year's measurements, which replace the upper limits with\nactual measurements. The abrupt switch in stratospheric circulation at the\n203","end of March came as a surprise; it had not been noticed previously and in\nsome way it must reflect the onset of heating in the upper stratosphere near\nthe spring equinox.\nWe have also begun to use the diode array spectrometer to study the\nchange in stratospheric NO 2 during the day. Previously we had been limited to\nmeasurements at sunrise and sunset and had found that unexpected anomalies\nexisted in the morning/evening ratio of abundance; now we are beginning to\nobtain measurements during the entire day and night which should help to\nclarify these anomalies.\nThe full analysis of the effect of the El Chichon dust cloud upon\nstratospheric NO2 is nearing completion. The very large reduction in NO2\nproduced by the cloud remains unexplained; doubtless it involves heterogeneous\nsurface reactions about which little is now known.\nThe first major study of stratospheric NO 2 using data from the SME\nsatellite has been completed, and we continue to analyze more recent\nobservations in collaboration with colleagues at the University of Colorado.\nWe also have analysed measurements from SME in the nadir; these permit\ndetection of NO2 in the troposphere produced both by lightning and by human\nactivity. For the first time such measurements can be obtained on a global\nbasis and not just locally.\nA second diode array spectrometer has been used at Fritz Peak Observa-\ntory to study NO, 3 and NO2 in the troposphere in collaboration with colleagues\nin the Atmospheric Sampling group. A year's measurements are under analysis\nand already confirm our earlier conclusion that NO 3 is strongly scavenged in\nthe troposphere as well as in the stratosphere; once again the scavenging\nmechanism remains unknown as does its role in cleansing the troposphere of\nnitrogen oxides.\nAn unexpected periodic oscillation in stratospheric OH has been dis-\ncovered; it remains unexplained.\nAn automatic instrument using twilight airglow to measure the atmospheric\ndensity at 300-400 km from the ground is now fully operational; the first\nmeasurements of thermospheric winds using molecular emissions have also been\nmade.\nPlans FY 1985\nWe shall continue to use and improve the long-path absorption facility to\nstudy NO2 and NO 3 in the troposphere in an attempt to understand more about\nthe removal of nitrogen oxides from the troposphere. We also plan to attempt\nmeasurements of other tropospheric species using this facility.\nThe diode array spectrometer will be used for further study of strato-\nspheric NO 3 and NO2, with much improved instrument sensitivity.\nAnalysis of the NO2 measurements from SME will continue with emphasis on\ntropospheric NO2 produced anthropogenically and by lightning.\n204","We shall continue the long series of measurements of stratospheric OH\nwhich are unique and yielding new surprises.\nATMOSPHERIC CHEMICAL KINETICS\nThe primary activity of the Atmospheric Chemical Kinetics program is the\nexperimental investigation of chemical reactions that are important in the\natmosphere. Although the research is focused on the effects of man-made\nchemicals, a second objective is to understand the natural, unperturbed\natmosphere. The information obtained in this program includes the rates and\nmechanisms of chemical reactions, thermochemical and spectroscopic data, and\nphotochemical measurements.\nThe chemistry of the stratosphere is of great interest because of the\npotential for humans to alter the ozone layer inadvertently, with disastrous\nconsequences. First, the possibility of an ozone reduction from exhaust\nchemicals released in stratospheric flights of supersonic aircraft was con-\nsidered. This brought worldwide attention to the potential for a global\nproblem: an increase in biologically harmful UV radiation at the Earth's\nsurface, caused by the reduction in stratospheric ozone. Later, chlorine-\ncontaining halocarbons and nitrogen fertilizers were identified as potential\nthreats to stratospheric ozone. In addition to the effects of increased UV\nradiation on biological systems, changes in the chemical composition of the\natmosphere may also produce climatic changes.\nTwo major environmental problems are associated with the chemistry of\nthe troposphere: photochemical air pollution and acid precipitation. Photo-\nchemical air pollution or smog is generally limited to urban and near-urban\nareas. It involves the formation of chemicals such as ozone and peroxy com-\npounds, which damage or irritate plants and animals. These chemicals are\ngenerated in air by a complex reaction scheme involving nitrogen oxides,\noxygen, hydrocarbons, carbon monoxide, and sunlight. Usually the reactant\nchemicals are transformed into their toxic products in the vicinity of the\nsource. In acid precipitation, sulfur and nitrogen source compounds may\ntravel over large distances before they are transformed into strong acids\nwhich are deposited in remote rural locations. A hazard of these acids is\nthat they can dissolve toxic metal compounds and the metals then damage plants\nand wildlife.\nMost chemical reactions that take place in the troposphere and strato-\nsphere involve free radicals. These are atoms or molecules characterized by\na high reactivity, which often results from having one or more unpaired elec-\nAL\ntrons. These reactions define the formation and destruction of atmospheric\nozone, the oxidation of natural and anthropogenic chemicals released into the\natmosphere, and formation of acid rain. The Atmospheric Chemical Kinetics\nprogram emphasizes quantitative studies of the rates and mechanisms of the\nimportant gas phase reactions of atoms and radicals. Studies are made over a\nwide range of temperatures and pressures to simulate conditions in the atmos-\nphere.\n205","Accomplishments FY 1984\nTwo experiments, a laser magnetic resonance spectrometer (LMR) and a\nchemical-ionization flowing afterglow (CI-FA), have been used to study the\nmechanism by which sulfur dioxide, SO2, is converted to sulfuric acid, H2SO4\nin the atmosphere. This process is a major source of uncertainty in modeling\nacid precipitation chemistry. The central issue is whether odd hydrogen radi-\ncals, OH or HO are consumed in the conversion process. If radicals are con-\nsumed, a reduction in SO2 emissions would not necessarily produce a propor-\ntionate reduction in the amount of H2SO4 deposited in critical areas. This\nfollows because the present rate of H2SO4 production may be limited by the\nnumber of odd hydrogen radicals produced and not by the amount of SO2 released\ninto the atmosphere. Recent experiments in other laboratories have provided\nindirect evidence that the gas phase SO2 oxidation process may not consume\nradicals. Our direct LMR study confirms these experiments and shows that the\nOH\nradical that reacts with SO2 in the primary process is regenerated as an\nHO2 radical, when oxygen is present. The CI-FA experiment has directly\nestablished that the second product of the critical reaction is sulfur\ntrioxide, SO3 The SO3 product is probably rapidly converted to H2SO4 by\nwater vapor and on the surface of droplets and aerosols. The proposed mech-\nanism is described by the following scheme:\nOH + SO2 + M HOSO2 + M\nHOSO2 + O2 HO2 + SO3\nSO3 + H2O H2S04\nThe reaction of nitrate radicals, NO 3 with nitric oxide\nNO 3 + NO 2NO\nhas been studied using laser-induced fluorescence detection of NO\nThis\nreaction is used for laboratory calibrations of NO concentrations and is\nimportant in nighttime urban chemistry. The rate coefficient at room\ntemperature was found to be about 50% larger than the accepted published\nvalue. Preliminary results at low temperatures show that it has a nega-\ntive temperature dependence.\nThe kinetics and transport properties of gaseous sodium, Na, have been\nstudied in a fast-flow reactor with resonant fluorescence detection of Na.\nSodium is deposited in the upper atmosphere by meteors. It was recently pro-\nposed that the presence of Na in the stratosphere could modify the chemistry\nof chlorine species that have been shown to be effective ozone destruction\ncatalysts. This study has shown that the reaction of Na with ozone is very\nrapid and that one product undergoes a second rapid reaction with ozone,\nwhich regenerates the Na. The existence of a catalytic cycle involving Na and\nozone has not been previously reported. It is unlikely to be very important\nin the stratosphere because the concentrations of free sodium are SO small in\nthat region, but it may be of some significance at higher altitudes. The rate\ncoefficient for the reaction of Na with chlorine, C12, was found to be very\nlarge. The diffusion coefficient of Na in helium was also measured.\n206","A study of the reaction of chlorine monoxide, C10, with hydroxyl radicals\nhas been completed using an LMR experiment. This reaction is important in\nthe stratosphere because it involves two\n(a)\nC10 + OH HO2 + C1\n(b)\nHC1 + O2\nkey chemical species. If path (b) is followed, the reaction becomes extremely\nimportant as a mechanism for converting reactive chlorine radicals (C10) to\nthe inert form hydrogen chloride. The results of this study indicate that the\nrate coefficient is about two times larger than that found in two previous, less\ndirect studies. The yield of hydrogen chloride is small but the uncertainty\nlimits in the present result do not place it at the insignificant level.\nThe temperature dependence of the reaction was also measured. The kinetic data\non path (a) were used to establish the thermochemistry of the hydroperoxyl\nradical, HO2.\nThe HS radical has been detected in an LMR experiment. This development\nmakes it possible to study the kinetics of HS which is important as a precur-\nsor to sulfuric acid. HS is known to be an intermediate in the atmospheric\noxidation of H2S and is thought to be involved in the oxidation of other\nsulfur compounds such as cos and CS\nA new experiment employing a high-resolution Fourier transform spectrom-\neter has been developed to evaluate the products of atmospheric radical re-\nactions. The experiment consists of discharge and hot wire radical sources, a\nreactor, a 1.6-m-long multipass absorption cell with a high-speed pump, and\nthe Fourier transform interferometer. The first tests with this system have\ndemonstrated that product molecules are detectable in the concentration range\n109 to 1011 molecule cm 3\nTests were performed using hot metal wires with the objective of\ndeveloping new sources of atoms and small radicals. The metals tested\nwere platinum, iridium, tungsten, nickel, and nichrome. The species\ngenerated were atomic hydrogen, oxygen, fluorine, chlorine, and hydroxyl. All\nwere detected by resonant fluorescence. Both hydrogen and oxygen atoms were\ngenerated in high concentrations on several different surfaces. No favorable\nsource was found for fluorine, chlorine, or hydroxyl radicals.\nStudies of collisional deactivation of vibrationally excited NO were\ncarried out in collaboration with scientists in several laboratories in\nEurope. This process is very important in the upper atmosphere and in per-\nturbed atmospheres. The presence of vibrationally excited NO in the atmos-\nphere is of concern to systems that use infrared wavelengths for measurements\nAL\nor detection. It was found that vibrationally excited NO ions are\ndeactivated rapidly by N 2 and slowly by O2. A theoretical model that de-\nscribes the deactivation process was developed and found to be applicable to a\nlarge variety of vibrational deactivation processes involving ion species.\n207","Plans FY 1985\nA new experiment to study gas phase reactions at atmospheric pressure\nwill be initiated. Free radicals for these studies will be generated by\npulsed laser photolysis of stable molecules. Radical detection will be\nachieved using resonant fluorescence, laser-induced fluorescence, or longpath\nabsorption techniques. This experiment will be directed toward investigating\nreactions that are thought to exhibit a pressure dependence and are related to\nthe formation of acid species in the troposphere.\nAn experiment will be developed to study the products of atmospheric\nphotochemical processes. Although a great deal is known regarding the rates\nof such reactions, there is often a major uncertainty associated with the\nproduct yields. The products' identities are critically important in deter-\nmining the role of a reaction in the atmosphere. The objectives of this ex-\nperiment will be to identify and quantify the products of photochemical\nprocesses such as the photolysis of NO 3 and the reaction of (1D) with N20.\nVarious optical techniques and mass spectrometry will be used to measure the\nproduct yields.\nFurther studies will be carried out on the SO2 oxidation mechanism.\nFirst an effort will be made to measure the efficiency of the conversion of\nHOSO2 to HO2 and SO3 Then a study of SO3 kinetics will be initiated using\nchemical ionization detection to see if the gas phase reaction proceeds with a\nsignificant rate.\nThe kinetic studies of NO 3 reactions will be continued. The temperature\ndependence study of the NO + NO 3 reaction will be completed first; then the\nreaction of NO2 with NO 3 will be investigated as a function of temperature and\npressure.\nThe reaction of Na with ozone will be studied further with the objec-\ntive of measuring the rate coefficients associated with the catalytic ozone\ndestruction cycle. The temperature dependence of these processes and the Na\ndiffusion coefficient will also be studied.\nThe laser magnetic resonance detection of HS radicals will be pursued\nwith the objective of studying the reactions of HS with atmospheric gases\nsuch as O2, 03, and NO. A search for the HSO radical, which is expected to\nbe the product of the 03 and NO2 reactions, will also be made.\nProduct detection studies will be continued with the Fourier transform\nspectrometer experiment. The current experiments on unstable molecules such\nas HOONO and HOONO2 will be extended to include searches for OH and HO2 rad-\nicals.\nThe collaborative studies of ion-molecule reaction kinetics will be\ncontinued. The work on the deactivation of vibrationally excited ions will be\nextended to cover a large range of temperatures and kinetic energies and dif-\nferent ion-neutral systems. Data obtained in other laboratories on the ion\ncomposition of the stratosphere and troposphere will be analyzed to gain in-\nformation on the concentrations of critical trace species.\n208","SPACE ENVIRONMENT LABORATORY\nHarold Leinbach\nActing Director\nBoulder, Colorado\nDirector\nO/P\nDep. Director\nCooperative\nESG\nCRP WRP PROFS WMP\nInstitutes\nNSSL\nWPL\nAL\nSEL\nAOML\nPMEL\nGLERL\nGFDL\nARL\nThe Space Environment Laboratory conducts research and provides services\nin the solar-terrestrial field. This field concerns the relationship between\nsolar activity and geophysical effects, which can adversely affect activities\nincluding communications, transportation, energy dissemination, and national\ndefense.\nThe focal point for the nation's present solar-terrestrial services is in\nthe Space Environment Laboratory at Boulder, where, with the cooperation of\nthe Air Weather Service, the monitoring and forecasting services are carried\nout to meet a wide variety of civilian, military, commercial, and Federal\nagency requirements. Laboratory activities include the real-time collection\nof solar-terrestrial data; the issuance of forecasts, alerts, and warnings of\nadverse solar-terrestrial conditions; the archiving and processing of solar-\nterrestrial data from all over the world; and the development of a better\nunderstanding of the behavior of the solar-terrestrial environment to yield\nsignificant service improvements.\nSEL is composed of three Divisions: the Research Division, the Systems\nSupport Division, and the Space Environment Services Division. The three\ndivisions work cooperatively in providing real-time space environment services\nand conducting the necessary supporting research and development activities.\nSEL\nHighlights of the year include the installation of the new Space Environ-\nment Laboratory Data Acquisition and Display System (SELDADS II), which will\nreplace the obsolescent SELDADS I, and the inauguration of the satellite data\nrelay system, which distributes solar-terrestrial data to users via satellite\ndata relay.\nFor the second time, Congress restored SEL's annual appropriation.\nHowever, the issue of the cut contained in the President's budget will arise\nagain for FY 1986.\n209","SPACE ENVIRONMENT SERVICES\nThe Space Environment Services Center (SESC) in Boulder is operated\njointly by the National Oceanic and Atmospheric Administration (NOAA) and the\nAir Force Air Weather Service (AWS) and exists to provide predictions, alerts,\nand real-time information describing solar geophysical disturbances to users\nthroughout the United States. In addition, it is designated the World Warning\nAgency (WWA) for the International Ursigram and World Days Service (IUWDS),\nwhich is operated under the International Council of Scientific Unions. SESC\ncollects data from its own sensors, from cooperating agencies and institu-\ntions, and from other countries, both through IUWDS and through bilateral\nexchange agreements. The data collected include solar images and measurements\nof other parameters that characterize the Sun, the interplanetary medium, and\nthe Earth's magnetosphere and ionosphere.\nSolar activity forecasts, geomagnetic forecasts, and warnings of events\nin progress as measured by real-time observations, are valuable to a great\nvariety of users. For example, the NASA Space Shuttle program uses this\ninformation in orbital planning and planning for astronaut safety. Iono-\nspheric communications, including low-frequency navigation systems (Omega),\nare perturbed during strong flares, proton events, and geomagnetic storms; the\nspace environment forecasts and warnings aid users in coping with the iono-\nspheric disturbances. The orbits of navigational satellites may be modified\nby increased density of the heated upper atmosphere during magnetic storms.\nThe Navy issues corrected satellite ephemerides based on the forecast or\nobserved level of magnetic activity. The same magnetic activity can induce\nstrong voltage and current transients in electric power distribution lines,\nleading to possible system outages. In long pipelines, the induced currents\nmay upset cathodic corrosion protection systems. In both situations, cus-\ntomers utilize geomagnetic forecasts and warnings to minimize adverse effects\non systems. Many geophysical prospecting companies using airborne magneto-\nmeters will avoid flights during the magnetically disturbed conditions that\nwould affect measurements.\nAccomplishments FY 1984\nSERVICES\nForecasts, used by about one-third of SESC customers, consist primarily\nof daily predictions of solar and geomagnetic activity, and of other standard\nmeasures of solar variation such as the 10-cm radio flux. Most of the\nforecasts are for the following 3 days, although forecasts for 27 days are\nmade for the 10-cm flux band for the global geomagnetic index, Ap. SESC\nmaintained a full schedule of daily forecasts through FY 1984.\nAlerts of solar activity and geomagnetic disturbances are issued in six\nmajor categories when disturbances exceed any of several increasing thresholds\nset to meet users' needs. Computers automatically search the incoming real\ndata for variations that may indicate onset of a disturbance, but alerts are\nissued only after the suspected disturbances have been reviewed by trained,\nexperienced personnel. In FY 1984, the automated alert system detected 865\nevents, but subsequent review showed that alerts for 29% would have been\n210","wrong. The actual alerts issued by SESC after human correction contained an\nerror rate of 0.5%\nIndices, summaries, and data allow users to diagnose problems in oper-\nating systems or to plan the execution of scientific experiments that must be\ncarried out under specific environmental conditions. The indices and summar-\nies issued by SESC in FY 1984 were based on standard 3-h and 24-h intervals.\nSESC operations were carried out in FY 1984 by a staff of NOAA and Air\nForce forecasters and solar-technicians providing services 24 hours per day, 7\ndays per week. The forecase center, located in Boulder, moved into new\nfacilities in FY 1984. The new facility is designed to provide the duty staff\nwith ergonomically correct, easy-to-use data displays, computer terminals, and\ncommunication equipment.\nREAL-TIME DATA\nSESC collects data from its own sensors, from cooperating agencies and\ninstitutions, and from other countries through international exchange\nagreements. The result is a pool of complementary data that allows a\nreal-time assessment of conditions in the solar-terrestrial environment from\nthe Sun through interplanetary space and down into the Earth's environment,\nincluding the ionosphere and magnetosphere. The types of data available to\nSESC in FY 1984 are discussed below.\nSolar Optical Observations\nSolar observations with optical telescopes provide information on the\nstate of the solar atmosphere (quiet or disturbed), such as the presence of\nactive regions and the global distribution of solar magnetic fields. The\nobservations are used to identify regions of high potential for solar flares,\nfilaments with high probability of eruption, and coronal holes (sources of\nhigh-speed solar wind).\nThe major sources of solar optical data are the AWS global network of\nobservatories, the Australian Dept. of Science observatories in Australia, and\nthe U.S. National Solar Observatories at Kitt Peak and Sacramento Peak.\nSolar Radio Observations\nSolar radio telescope observations provide an indication of the energetic\nsolar disturbances, acceleration of energetic electrons, and the passage shock\nSEL\nwaves through the solar atmosphere. Sources of data include the Air Weather\nService global network, the Canadian solar radio measurements from Algonquin,\nand measurements made at Boulder, Colo.\nGeomagnetic Field Observations\nGeomagnetic observations provide quantitative information on the\ngeographic extent and severity of the geomagnetic variations that occur as a\nresult of solar wind and/or magnetospheric disturbances.\n211","Satellite observations of the geomagnetic field at geosynchronous orbit,\nand ground-based data from an 18-station network (through the cooperative\nefforts of the Dept. of the Interior, National Science Foundation, and\nUniversities of Alaska and New York State), are transmitted in real time to\nSESC to monitor the effects of solar wind disturbances on the Earth's\nmagnetosphere.\nSolar X-ray Observations\nSolar X-rays produce interruptions to ionospheric communications\nsimultaneously with the sighting of the optical solar flare. Continuous\nobservations of solar X-ray emissions from the whole Sun are provided by the\nspace environment monitors on the geostationary operational environmental\nsatellites (GOES). Data are collected at Boulder by radio link directly from\nthe satellites.\nEnergetic Particle Emissions\nSolar emissions of high energy protons, electrons, and alpha particles\nmay cause radiation damage to satellite systems and are potential health\nhazards to astronauts in space and to passengers in aircraft flying at high\naltitude. The same particles also cause outages on high frequency (HF) radio\ncircuits in polar areas and are correlated with errors in very low frequency\n(VLF) navigation systems. The presence of upper atmosphere heating, a\nconsequence of the magnetospheric particle precipitation and Joule heating by\nionospheric currents, can be inferred by the magnitude of the total energy\ndeposition measured by sensors on polar-orbiting satellites.\nParticle observations are made on NOAA satellites-- - the polar-orbiting\nTIROS (Television and Infrared Observation Satellite) and the geosynchronous\nGOES.\nSolar Wind Observations\nSolar wind perturbations presage the occurrence of geomagnetic storms at\nthe Earth. Preliminary solar wind data from interplanetary spacecraft are\nreceived in real-time by SESC. These data include solar wind density and\nvelocity and the interplanetary magnetic field direction and amplitude. The\nprimary source of these data, the NASA International Sun-Earth Explorer\n(ISEE-3), was dispatched from its location between the Earth and the Sun\nin FY 1984 and sent on a comet encounter mission under the name International\nCometary Explorer (ICE). This has resulted in a decrease in its usefulness to\nspace environment operations.\nOther Geophysical Data\nOther geophysical data (including cosmic ray, ionospheric, and geomag-\nnetic) are collected in Alaska at a station jointly operated by the Air\nWeather Service and NOAA, from the NOAA observatory at Table Mountain near\nBoulder, and from various sources in an international exchange program.\n212","DATA DISPLAY SYSTEMS\nThe primary data system in the service operation is the Space Environment\nLaboratory Data Acquisition and Display System (SELDADS) for collecting,\nprocessing, integrating, storing, and displaying solar-geophysical data from\nobserving systems of the DOC, DOD, DOE, DOI, and the National Science\nFoundation, as well as international data exchange programs. Real-time data\nentering SELDADS are converted to engineering units, quality controlled,\ntested for significant solar-geophysical events, and stored for later access\nand archiving. Processing of the data occurs continuously, 24 hours per day,\n7 days per week. The SESC forecasters are the primary users of the data base.\nDisplays and interactive analyses of the data are used by SESC to provide its\nforecasts, alerts, and summary data. Data are also provided to meet the\noperational requirements of the Department of Defense and other national\nusers. Summary data are transferred from SELDADS after 1 month for archiving\nin the National Geophysical Data Center. SELDADS was operational more than 99%\nof the time in FY 1984.\nDISTRIBUTION OF SERVICE PRODUCTS\nService products are distributed to users in a number of ways commensu-\nrate with customer needs: Radio broadcasts on the shortwave time service WWV\ncontain hourly announcements of space environment indices and predictions;\nusers can call a tape-recorded message in Boulder at their own expense to\nobtain the same information; alerts of disturbances are distributed by tele-\nphone to users who need such information in real time; teletype messages that\ncontain more information than can be included in verbal messages are sent on a\ncollect basis to users who do not have access to other networks.\nIn its role as the World Warning Agency for the IUWDS, SESC distributes\nits products to regional warning centers on each of the major continents.\nA major new development in FY 1984 was the initiation of a satellite\nbroadcast service for distribution of the space environment services. The\nbroadcast includes a standard package of forecasts, alerts, and indices that\nserve the widest practical user community. A standardized data format is\naccessible by users with microcomputers, large-scale computer systems, or\nstandard printer systems For example, the user may display a real-time plot\nof solar X-ray flux. Information can be used by commercial companies to\nprovide further specialized services to segments of the user community.\nTECHNICAL IMPROVEMENTS IN SERVICES\nGeomagnetic forecasts and alerts are required by approximately two-thirds\nSEL\nof SESC's customers. An improved format for geomagnetic forecasts was devel-\noped during FY 1984. Forecasts for 1-, 2-, and 3-day periods indicate the\nlikelihood that the activity level will fall in each of six categories of\ndisturbance, from very quiet to very stormy. A \"climatological\" data base\nof\nmagnetic records is being established to provide numerical guidance for the\nforecaster and to give a basis of comparison for forecast verification.\nA study was begun to establish the operational needs and priorities for\nimages and magnetograms of the Sun. It is clear that in the future images\n213","will be transmitted from remote observatories in digital format, avoiding the\ncumbersome photographic processes needed to record the images and transmit\nfacsimile pictures. The use of digital images will open the way for\nquantitative analysis and comparison of images. For example, these new tech-\nniques will facilitate the creation of synoptic solar maps, which even now in\ntheir hand-drawn format are a primary input to forecasting of solar activity.\nThe requirements for a new image system, called SELSIS (Space Environment\nLaboratory Solar Imaging System) were formulated, and procurement of some of\nthe components was initiated.\nThe measurement of magnetic shear in active regions of the Sun is being\ninvestigated as a way of improving flare forecasts. Shearing of the fields\nleads to storage of energy, which then may be converted into various forms of\nparticle and electromagnetic radiation in a catastrophic process, identified\nas a solar flare. Advance knowledge of the total energy available would\nassist forecasters in estimating the maximum size flare that might occur. The\nrate of energy build-up may indicate when an unstable level may be reached and\na flare will begin.\nPlans FY 1985\nSERVICES\nThe basic services carried out in FY 1984 will be continued in FY 1985,\nincluding real-time monitoring, data collection, and processing; the issuance\nof forecasts, alerts, and indices from the forecast center of SESC on a\n24-hour per day, 7-day per week basis; and the distribution of service\nproducts.\nSeveral improvements in services are planned for FY 1985:\nThe new geomagnetic forecast format will come on line as part of the\nPhase I software for SELDADS II.\nA new product, to be disseminated in SESC's weekly data report, will\nprovide a continuous plot of conditions in the space environment at\nsynchronous satellite orbit. The new data displays will assist satellite\noperators in rapid diagnosis of problems with their spacecraft; problems have\nincreased because of the satellites' electronic components, which are\nsensitive to disruption in the space environment.\nRenovation of the forecast facility will be completed with the installa-\ntion of new graphics displays that are part of the SELDADS II system. The new\nequipment will provide displays that tell the current status of disturbances\nin the solar terrestrial environment, and the operational status of the\nSELDADS computers and of the communication links into and out of the service\ncenter. The forecast personnel will spend much of their non-forecast duty\ntime in establishing requirements for the content, format, and protocol for\neach of the display systems being constructed as part of the new SELDADS. The\nprimary new activity will be the implementation of SELDADS II, which is\ndescribed in the last section.\n214","Other activities will be the design of a processor that will be used to\ncollect real-time data from the NASA International Cometary Explorer (ICE).\nThe processor will allow the solar wind data from the ICE to continue to be\navailable in real time at least some of the time, even though the ICE is in a\nless desirable orbit for forecast services than was the ISEE.\nTECHNICAL IMPROVEMENTS IN SERVICES\nThe project to improve the geomagnetic forecast format will move into\nforecast operations as the first phase of SELDADS II comes on line. The\ndevelopment work on the use of shear as a flare forecaster will continue in\ncooperation with the Air Force observatories. This work will also be\nintegrated into the more advanced capabilities to be developed on the image\nanalysis system including the capability to automate some of the current\nmanual analysis of the synoptic type solar image data.\nPresent knowledge indicates that solar flares, and solar mass ejections\nassociated with solar filaments and the steady emission from coronal holes,\nare capable of producing geomagnetic storms. A study will be made of why\nthese occur for only about one-half of the observed solar events judged to be\ncapable of producing geomagnetic activity.\nRESEARCH AND DEVELOPMENT\nResearch and development are carried out in the Space Environment\nLaboratory by the Research Division and the Systems Support Division.\nThe Research Division carries out research in the field of solar-\nterrestrial relations, with the objective of improving our understanding of\nthe effects of solar activity on human activity.\nThe Systems Support Division provides general support to the Space\nEnvironment Services Division and to the Research Division in planning,\ndevelopment, and provision of Instrument and Data systems.\nAccomplishments FY 1984\nOPERATIONAL SATELLITE INSTRUMENTATION\nData from operational Space Environment Monitors (SEM) which are carried\non the NOAA TIROS and GOES spacecraft are essential to the operation of the\nSEL\nNational Space Environment Service. The provision of instruments of existing\ndesign to replacement spacecraft and the development of new or improved\ninstruments for existing or new spacecraft designs is therefore a very\nimportant supporting activity.\nInstruments are normally produced by contractors (or sub-contractors) to\nthe National Aeronautics and Space Administration, which acts in turn as a\ncontractor to NOAA for the provision of the entire operational satellite. SEL\nsets the requirements for the SEM's and assists with the technical supervision\n215","of the instrument contractor. SEL has also been asked by NASA to perform\nrecalibration and repair as necessary on off-the-shelf instruments awaiting\nflight, and also recently to requalify one existing GOES High Energy Proton\nand Alpha Detector (HEPAD) instrument, and assemble a second from spare parts\nfor the GOES-G and -H program. This detector provides operational information\non radiation hazards caused by very high energy solar particles during very\nlarge solar flare events.\nDuring the year, SEL delivered the first HEPAD to the GOES contractor.\nThe second instrument is expected to be delivered in October.\nThe existing TIROS SEM instruments awaiting flight were supported as\nnecessary. Two Medium Energy Proton and Electron Detector (MEPED) units were\nrepaired and requalified.\nThe GOES-NEXT program was supported by finalizing the SEM requirements\nand revising the resulting specifications. The spacecraft Request for\nProposals has been issued, and responses will be under review at the close of\nFY 1984.\nThe final report was issued on the development work carried out on the\nprototype of an X-ray imaging instrument for operational use on the GOES\nseries of spacecraft. The imager is currently included in the GOES-NEXT\nRequest for Proposals, as an example of an instrument for which an expansion\ncapability is desired. This provision will enable the imager to be added when\nfunding becomes available.\nThe framework of a new software system for the off-line processing of\nGOES and TIROS data was completed during 1984. The new system was rendered\nnecessary by changes in the satellite telemetry system. Off-line processing,\ni.e., separate from real-time processing that provides data to SESC, provides\na magnetic tape data base for use within SEL. This is used for data quality\ncontrol and research and development on new service applications of the data.\nThe tapes are also archived with NESDIS World Data Center-A for use by other\nscientific organizations. The new system will provide explicit routine\nquality control and is also being designed so that as much as possible\nof the system can ultimately operate within SELDADS II rather than the ERL\ncomputer system.\nSELSIS-SEL SOLAR-IMAGING SYSTEM\nDuring the year a working group was formed to study the future direction\nof the handling of image data in SESC. All solar image data are currently\nused in photographic form, and are obtained from remote observatories by wire\nphoto systems. These systems are old and in need of replacement. The working\ngroup recommended that, rather than replace the existing systems, we move to\ndigital image transmission, storage, and display, which is now becoming prac-\ntical at reasonable cost. The recommendation was accepted and implementation\nis under way.\nThe cooperating observatories that provide the images are moving to make\nall data available in digital form. The benefits expected are improved image\nquality and, most importantly, the ability to combine image data from more\nthan one source and to carry out quantitative image processing. The system\n216","will bring images from Kitt Peak National Observatory, Holloman AFB, and our\nlocal H-alpha telescope into the SESC storage system and also permit the\nexchange of images with NASA Johnson Space Center during Shuttle Spacelab\nmissions that require this support.\nThe system will be implemented in coordination with existing plans to\nacquire a scientific graphics workstation; a second identical workstation will\nbe the basis for the SESC image display and processing system. All the\nnecessary hardware is now on order.\nSOLAR PHYSICS\nActivity was directed toward research to improve medium- and long-range\nsolar predictions (in the range of weeks to 10 years) and toward basic under-\nstanding of the structure and evolution of the solar corona, as a prelude to\npredicting the propagation of solar disturbances toward the Earth and other\nbodies in the solar system. Statistical studies of geomagnetic and sunspot\nactivity resulted in advances in predicting the levels of solar-terrestrial\nactivity as much as a decade ahead.\nSolar Mapping\nThe goal of this activity is to replace the daily maps of the Sun, drawn\nby hand, with maps and charts plotted from digital files stored on computer\ndisks. The digital data will serve to make SESC products more uniform and\nobjective, and provide a data base for computer manipulation. An immediate\nimprovement is realized in the accuracy of overlying images from different\nobserving systems, taken at different times. Software developed this year\npermits computer production of the daily disk solar map, complete with annota-\ntion of SESC serial numbers for solar active regions. Provision is made to\nallow plotting of a map from data obtained one or more days earlier so that an\noperational map can be constructed in times when weather or equipment problems\nprevent receipt of solar image data.\nImplementation of these mapping procedures will eliminate duplication of\neffort in producing the daily maps for real-time use and the production of\nsynoptic charts used in long-range forecasting and in support of solar-\nterrestrial research. The conversion to a digital data base will permit\ncoupling of solar maps with digital solar image processing as it is developed.\nDevelopment of computer displays from the digital data files can proceed with\ncurrent data rather than delaying this development until advent of the digital\nimaging. This work will facilitate application of research involving large-\nscale solar magnetic fields and the solar corona.\nSEL\nWork continued, under contract to NASA, to provide real-time\ncommunication of daily maps of solar magnetic fields from Stanford University\nto SESC. The Stanford maps are plotted at the same scale and format as the\nmaps generated from other solar images available to SESC.\nA computer program was developed for using these data to compute the\ndistribution of large-scale solar magnetic fields at the height above the\nsolar surface where these fields are expected to couple directly to the inter-\n217","planetary magnetic fields. This quantitative model of the solar coronal\nenvironment will be a basis for predicting the propagation of solar distur-\nbances from the Sun.\nThe data base of H-alpha synoptic charts (global maps of the Sun for each\ncomplete 27-day solar rotation) was maintained and prepared for archiving.\nThese edited charts have been used to construct time series of limited\nlatitude zones of the Sun for monitoring long-term, large-scale evolutions.\nThe formation of strong centers of sunspots and solar flares and the\noccurrence of large, stable coronal holes have been tentatively associated\nwith patterns of convergence and divergence, respectively, in the evolving\nlarge-scale patterns of magnetic fields. The maintenance of the data base on\nlarge-scale solar activity is a necessary prelude to the development of\npractical methods for making 27-day solar-terrestrial predictions.\nLarge-Scale Solar Activity\nA collaborative study of solar maps combining large-scale magnetic-field\npatterns with filaments and coronal holes has resulted in a detailed\ndescription of the process of reversing the polarity of the poles of the Sun.\nThe polar reversal occurs a year or two after the peak in the 11-year cycle.\nStudy of this process may offer clues to the physics of the solar cycle and a\nbasis for long-term solar predictions. This study found that the process was\ndiscontinuous, and occurred in organized meridional flows rather than through\na diffusive process.\nLong-range predictions of sources of strong X-ray flares have been\nresumed in support of NASA research programs directed toward solar and\nmagnetospheric physics. The prediction technique uses time series of H-alpha\nsynoptic charts to derive maps of velocities over the entire solar surface.\nAnomalies in the large-scale flows, such as excessive shear and convergence,\nprecede the occurrence of major sunspots.\nA new model for the formation and structuring of sunspot groups has been\ndeveloped from study of the relationships between sunspots and the largescale\nmagnetic fields.\nLong-Term Solar-Terrestrial Activities\nA study of recurrent geomagnetic activity led to a new index for\nseparating the recurrent component from the eruptive component in geomagnetic\nactivity. This study is being extended to use the index to make predictions\nof sunspot cycles several years earlier than previously possible.\nSolar Flare Evaluation\nProvisional mathematical models have been established for the early rise\nand decay of the X-ray flux from solar flares, as a step in the development of\nan automated means for early detection of X-ray flares and prediction of their\npeak intensity and rate of decay. If successful, the models will improve\npredictions of communication disruptions caused by solar X-ray bursts.\n218","Solar Active Regions\nA catalog is being compiled of outstanding active regions in terms of\ntheir X-ray flare production to link solar active region formation to the\nlarge-scale solar evolution. These data were used to update the correlation\nbetween sunspot class and flare activity reported at the Solar-Terrestrial\nPredictions Workshop sponsored by the Observatoire de Paris.\nCoronal Modeling\nWork continued on theoretical and empirical models of the solar corona.\nA study of the structure and electrical currents of the corona was completed.\nModeling of solar filaments is under way to aid in predicting instabilities\nover neutral lines that precede solar flares and coronal transients.\nAlgorithms have been produced for computing source surface magnetic field\ndistributions from photospheric magnetic fields, and calculating the connec-\ntion points between the Earth and the solar surface.\nINTERPLANETARY PHYSICS\nApproximately two-thirds of the SESC customers would benefit from\nimproved forecasts of the occurrence of magnetic storms. The results of\nstudies directed toward this objective are discussed below.\nIt is known that solar flares accompanied by Type II radio noise bursts\nare apt to produce shock waves in the solar wind, which travel through the\ninterplanetary medium and produce the geomagnetic storm.\nA comparison was made of the predicted times of arrival of shock waves at\nthe Earth and the observed geomagnetic storm sudden commencement for 59 solar\nflare events. The predictions used the Air Force Geophysical Laboratory\nalgorithms for shock-wave propagation based on the shock velocity at the Sun\ndeduced from Type II bursts. The median prediction was 1.35 hours late with\na\nstandard deviation of 6.9 hours. A \"Users' Guide,\" with instructions on\nreporting of these Type II shock velocities, has been distributed to all USAF\nsolar radio observing sites.\nPropagation of Solar Wind Disturbances\nA time-dependent, magnetohydrodynamic (MHD) numerical model for the pro-\npagation of shock waves through the interplanetary medium was tested using\ndata for a series of solar events in August 1979. Qualitative agreement, but\nSEL\nwith changes in phase and amplitude differences, was achieved with an\napproximation to a fully three-dimensional (3-D) model. Work has started on a\nfully 3-D, timedependent model starting with the special case of\nflare-generated shock waves Both the approximate and fully 3-D models are\ninitialized at 18 solar radii. Closer to the Sun, 2-D and the approximate 3-D\nmodel predictions of the structure of coronal disturbances have been compared\nwith many types of coronal observations in white-light, radio, X-ray, and UV\nwavelengths. This work opens up the possibility, from an operational\nviewpoint, that real-time observations of coronal structures can be used as\ninput for a fully 3-D model. Fundamental studies, using higher moment\n219","equations, were completed to demonstrate the need for incorporating thermal\nconduction and multi-fluid aspects into these interplanetary global\ncirculation model programs.\nGeomagnetic Activity Forecasts and Warnings\nThe approximate 3-D model was used with observed solar hydrogen-alpha and\nmagnetograph data (to provide \"best estimate\" of solar output) to give time\nseries of the Poynting energy parameter, and cross-tail electric field at\nEarth's location for a 2-week period in August 1979. This output could\nconceivably provide a forecaster with predictions to answer four questions:\nWill a disturbance occur? When will it occur? How large will it be? How\nlong will it last?\nMAGNETOSPHERIC PHYSICS\nResearch in the Magnetospheric Physics Area is directed toward under-\nstanding of the dynamical processes by which material and energy are\ntransported from the solar wind into the magnetospheric system, stored, and\neventually dissipated in the Earth's ionosphere. Both applications and\nsupporting research are pursued, directed toward enhancement of the quality\nand utility of the Laboratory's space environment products and services.\nPolar Cap Data\nThe first two volumes of a series of atlases of energetic particle\nobservations by instruments aboard the NOAA/TIROS series of low-altitude,\npolar-orbiting satellites have been published. These data cover the period\nfrom January 1979 through May 1983, and will be continued in subsequent\nvolumes to the present. These data permit the operational or research user to\nidentify solar cosmic ray and other event periods of interest, establish an\nevent chronology of importance to synoptic studies, and intercompare\nequivalent data from other satellites.\nOmega VLF Study\nA study was undertaken in support of the Omega Navigation System to\ninvestigate long-delayed (days) recoveries of the system signals following\ndisturbances caused by Polar Cap Absorption (PCA) events. System responses\nduring and following five large PCA events were compared with the associated\nparticle fluxes measured on the SMS/GOES and NOAA/TIROS series of satellites.\nA close correlation was found between the recovery of the VLF signals and the\nflux of energetic protons in the range of 4-8 Mev. A simple algorithm was\ndefined which allows the prediction of the VLF phase recovery based on the\nreal-time observations of the proton flux. Operational tests of this\nalgorithm have been implemented.\nData Support\nA compilation of information concerning the instruments constituting the\nSpace Environment Monitors aboard GOES satellites is being prepared. This\n220","summary will form a basis for the use of the data both in-house and by\nexternal groups.\nExternal Cooperative Support\nLaboratory scientists provided consultation and energetic particle data\nfrom the GOES and TIROS satellites to the Defense Nuclear Agency (DNA) for use\nits Long Wave Program, which studies the propagation of extremely low\nin\nfrequency (ELF) and very low frequency (VLF) waves at high latitudes.\nSatellite data and analyses were also provided to the scientific\ncommunity as a cooperative activity in the Middle Atmosphere Program (MAP), an\ninternational cooperative program under the aegis of the Scientific Committee\non Solar-Terrestrial Research directed toward the study of the structure and\ndynamics of the high-altitude middle atmosphere through coordinated high-\naltitude research rockets, and by ground-based and satellite observations.\nLaboratory scientists participated in NASA/Air Force working group meet-\nings on Spacecraft-Environment Interaction in order to evaluate the\nenvironmental causes of spacecraft anomalies and failure, and to assess the\noperational monitoring of the near-Earth environment needed to provide useful\nwarnings and forecasts of satellite disruptive periods. Also, there was\nparticipation in a NASA working group meeting on Spacecraft-Environment\nInteraction held at the U.S. Air Force Academy in October 1984.\nMagnetospheric Acceleration Processes\nApproximate analytic procedures have been developed to represent and\ncharacterize the magnetospheric tail acceleration process by which magneto-\nspheric particles are energized by the cross-tail electric field. These\nenergetic particles are precipitated into the auroral zones, and also provide\na significant source of charged particles to the Earth's ring current system,\nwhich is responsible for a major portion of geomagnetic disturbance. The\nlevel of geomagnetic disturbance is the single, most important parameter in\ndetermining disturbance to communications, power transmission, and satellite\nsystems. An extension of the original theoretical development of this\nimportant mechanism by SEL scientists has received broad acceptance by the\nscientific community.\nMagnetospheric Boundary Phenomena\nTheoretical work and model calculations continue on the dynamical pro-\nSEL\ncesses occurring at magnetospheric boundaries. Comparison is made between\nmodel calculations and satellite observations in the context of trying to\ndefine the reconnection process by which interplanetary field lines, convected\noutward from the Sun by the solar wind, interact with the geomagnetic field at\nthe magnetopause. Understanding boundary properties is crucial to under-\nstanding the processes by which solar wind energy is coupled to the magneto-\nspheric system.\n221","ATMOSPHERE-IONOSPHERE-MAGNETOSPHERE INTERACTIONS\nThe objectives of the research in the atmosphere-ionosphere-magnetosphere\ninteractions area are to understand the transfer of energy (both in the form\nof electrical and mechanical energy) from the Earth's magnetosphere into the\nupper atmosphere and to understand and characterize the various consequences\nthat may arise in the Earth's ionosphere and upper atmosphere because of this\nenergy input.\nThe observations from instruments on board the NOAA/TIROS series of\nspacecraft continued to be processed and used both in research and in a\ngrowing number of operationally oriented programs. Normally, about 96% of\nall\ndata gathered by these satellites is recovered and archived within 10 days\nof receipt. Difficulties with noisy data from the total energy detector on\nNOAA-7 were experienced at the end of FY 1983, and the NOAA-8 spacecraft\nsuffered a failure in June 1984. However, the NOAA-6 spacecraft was re-\nactivated and data are being received from that satellite. NOAA-9, scheduled\nfor launch in late 1984, will not contain a space environment monitor, which\nwill reduce these observations to a single spacecraft for the first time since\nJune 1979.\nWork continued on the development of the estimate of the power dissipated\nin the auroral atmosphere by precipitating particles, based on single passes\nof these satellites over the Earth's polar regions. Estimates of the total\namount of power being deposited into the atmosphere may characterize the\ndegree of geophysical activity and its consequences in a more quantitative\nmanner than is possible with conventional magnetic indices. In the course of\nthis study a set of statistical \"maps\" showing the global pattern of energy\ninput to the atmosphere for various levels of total power input was also\ndeveloped.\nThe statistical patterns of energy input show an isolated island of\nenergy input located at very high latitude at about 2 p.m., which is parti-\ncularly apparent at low levels of activity. Other researchers have pointed\nout that this particular location is also the site of a local maximum in other\ngeophysical phenomena, notably the intensity of currents flowing between the\nionosphere and a dynamo located in the magnetosphere. A study using the\nNOAA/TIROS data was conducted to determine the nature of the particle energy\ninflux at this location. The energy input is exclusively in the form of\nelectron precipitation having thin, auroral, arc-like geometries. Independent\nobservations demonstrated the disturbance introduced into the ionosphere by\nthis precipitation. Moreover, correlations of these TIROS data measurements\nwith those on board high-altitude scientific satellites suggest that the\nfundamental cause of this precipitation is a dynamo process driven in the\nouter magnetosphere by a direct solar wind interaction. The comparatively\nsimple geometry of this process may allow a theoretical analysis to be done,\nwhich in turn will shed light on the more complex nighttime magnetospheric-\nionospheric-atmospheric processes.\nNumerous scientific collaborations utilizing the NOAA/TIROS data were\nconducted during the last year. Generally, these involved the use of the data\nin conjunction with ground-based and satellite measurements of individual\ngeophysical events. In addition, the statistical maps of the energy input,\ncreated from the large data base of observations that now exists, are being\nused by a research group at University College, London, as an input to a model\n222","of upper atmospheric dynamics. The use of these data for such a purpose could\nbe of great benefit to the objective of deducing the density and temperature\nof the upper atmosphere from the satellite observations of total energy\ndeposition.\nThere were several instances of the use of the NOAA/TIROS data in support\nof operational programs. For the Department of Defense the historic\nobservations were used to determine the particle environment through which\nlarge, polar-orbiting satellites (such as the Shuttle) will be required to\npass. These particles, impinging upon the satellite, can produce malfunctions\nwhich, experience has shown, grow more frequent as spacecraft become larger\nand more complex. To this end, an analysis was done on the frequency and\nnature of the unusually large energy flux events that are encountered by these\nsatellites from time to time. This analysis was forwarded to the Jet\nPropulsion Laboratory for evaluation.\nIn the same vein, these data were supplied to NOAA's National\nEnvironmental Satellite, Data, and Information Service (NESDIS), and sometimes\ndirectly to a user, to assist in their interpretation of satellite system\nmalfunctions that often tend to occur repeatedly within a limited period of\ntime. One such instance centered around September 1983, and SEL was called\nupon to supply data from that period.\nPlans FY 1985\nOPERATIONAL SATELLITE INSTRUMENTATION\nThe Laboratory will participate in the review of contractors' proposals\nfor GOES-NEXT. The ongoing operational satellite space environment monitoring\nsensor program will continue to be supported by the delivery of the HEPAD for\nGOES-I and by any other technical support required.\nThe off-line processing system will be completed, and automatic, routine,\nquality control will be implemented whenever possible. The system will be at\nleast partially implemented on SELDADS II.\nSELSIS-SEL SOLAR-IMAGING SYSTEM\nProgramming for digital communication and image storage and display will\ncommence in early FY 1985. It is planned to have the system in limited\noperation by March 1985.\nSEL\nSOLAR PHYSICS\nIncrease the opportunities for achieving, and the plans for using, a\nspaceborne monitor for coronal transients, solar flares, and coronal\nstructures that influence the propagation of disturbances and material\nfrom the Sun.\nComplete operating manual for computerized, routine, solar mapping and\ntrain SESC staff so as to assure a reliable data base for both short-term\nand long-term solar-terrestrial predictions.\n223","Edit preliminary H-alpha synoptic charts for publication and for use in\ndevelopment of long-range solar forecasting.\nStudy large-scale patterns of solar magnetic fields and their relation to\nthe formation of centers of strong solar activity. Convert results to\nprocedures for use in SESC 27-day (and longer) solar-terrestrial forecasts.\nDevelop real-time computation of source-surface magnetic field configu-\nration above the solar surface for use in operational evaluation of solar\nevents. Refine communication and display of Stanford solar magnetic maps.\nExtend coronal modeling to more complex conditions at solar maximum. Add\ntheory of fine structure in magnetic flux tube under the influence of\nexternal fields. Continue modeling of solar filaments. Attempt to tie\nresults to efforts to model the interplanetary environment.\nRefine and continue to disseminate forecasts for the time of sunspot\nminimum and amplitude of Sunspot Cycle 22. Continue studies of other\nmethods for solar cycle predictions in comparison with methods developed\nby laboratory scientists.\nDevelop a computer technique for early recognition of an X-ray solar\nflare, prediction of the time of peak intensity, the magnitude of peak\nintensity, and the rate of decay.\nMake comprehensive study of coronal hole images at all observed wave\nlengths and determine utility for predictions of geomagnetic activity.\nInvestigate source of the semi-diurnal X-ray detector variations between\nwidely separated geosynchronous satellites.\nInvestigate epochal nature of solar activity (4-7 month \"pulses\") and its\nrelationship to the evolution of large-scale solar magnetic fields. This\nwill include study of the phenomenon of active/inactive solar longitudes.\nExamine whether these studies suggest practical steps toward long-term\nsolar-terrestrial predictions.\nImplement a verification system for one selected SESC forecast product.\nThis would be a cooperative project with SESC. It will address those\nbasic philosophies and principles that would be used in the future for\nbench marks of forecast algorithms and for decisions on directions of\nresearch efforts.\nINTERPLANETARY PHYSICS\nForecast Verification\nThe predictive capabilities of the approximate 3-D MHD model will be\ntested against additional real-events to better understand the effects of\ndifferent input parameters on the accuracy of the predictions.\n224","Propagation of Solar Wind Disturbances\nThe approximate 3-D model will be incorporated into the new scientific\nwork station computer. Additional graphical displays will be added, together\nwith a complete 360-degree ecliptic plane projection of propagating distur-\nbances. In collaboration with several contractors, a graphical capability\nwill be developed for the 3-D model as well as an extended heliolongitudinal\nand heliolatitudinal capability. The model will be expanded to handle various\nkinds of solar disturbances such as eruptive prominences, and coronal hole\nstreams, as well as solar flares. The solution to a two-component (electrons\nand protons), five-moment solar wind will be pursued together with a related\nstudy on the effect of an interplanetary electrostatic field in regions of\nhigh density, and magnetic field gradients, and electric charge separation.\nMAGNETOSPHERIC PHYSICS\nExtend the Energetic Particle Atlas series to include current data.\nContinue support to external users including Long Wave Navigation\nProgram, Spacecraft-Environment Interaction working groups, and\nsimilar activities.\nInvestigate the potential of GOES magnetometer data for prediction of\ngeomagnetic disturbance.\nBegin a study of numerical simulation techniques in magnetospheric plasma\nprocesses. Analytical work in this field has emphasized the MHD\napproach. It has become increasingly evident that approximations, such\nas charge neutrality, inherent in the MHD equations limit their\napplication to magnetospheric processes. Plasma numerical simulations,\nwhile complex, approach the problem at a microphysics level, where such\napproximations can be avoided.\nContinue theoretical and model boundary work on reconnection and plasma\nsheet boundary phenomena.\nATMOSPHERE-IONOSPHERE-MAGNETOSPHEREINTERACTIONS\nA senior researcher from the Atmosphere-Ionosphere-Magnetosphere\nInteractions group will spend FY 1985 as a visiting scientist at the\nStanford Space Telecommunications and Radio Laboratory and at the Lockheed\nResearch Laboratories, Palo Alto. These research groups are very active\nin the field of space research, and both are vitally concerned with the\nSEL\nimpact of the near-Earth environment upon both communications and space\nsystems. The research work performed during this period will greatly\nincrease SEL's understanding and expertise in this important field.\nRoutine processing of NOAA/TIROS data will continue, and arrangements\nhave been made to ensure that requests for data, particularly from\noperational sources, will be filled.\n225","SELDADS II\nThe Space Environment Laboratory Data Acquisition and Display System\n(SELDADS) provides computer-assisted access to solar-geophysical data from a\nvariety of satellites and ground-based observatories around the world in near\nreal-time. The SELDADS II system now in development will replace the aging\nSELDADS I system and provide for improved access, analysis, and display of\nthese data with increased reliability.\nAccomplishments FY 1984\nA new Data General MV10000 was installed in July in the newly prepared\nsite near the SELDADS I, which will remain in operation until the Phase I\napplication software of the new system is complete. Acceptance testing began\nin August. Software supplied will include a customized data base (software)\nsystem and a comprehensive graphics (software) system. A series of WICAT 150\ncomputers will serve as preprocessors to operate separately on each incoming\nand outgoing data stream to prepare the data for introduction into the main\nprocessor, which will concentrate on data base management and analysis software.\nStatus displays required for basic forecast center operation will be driven\nboth by preprocessors and by the main system to provide redundancy and\ncontinuity in the new system. The preprocessors will be identical so that one\nthat fails while handling high priority data can be replaced by another\nhandling lower priority tasks.\nA Project Management Panel to manage the development of software for the\nnew system has been appointed, and personnel for the development effort have\nbeen identified within the Laboratory. The conceptual design for the appli-\ncation software has been completed and the products to be generated in the\nfirst phase of the implementation have been identified.\nPlans FY 1985\nThe implementation will proceed in three phases. Phase I will provide a\ncapability equal to the present SELDADS I system, and after some period of\nparallel operation of SELDADS I and the Phase I system, SELDADS I will be\nturned off. Phase II software will implement analysis capabilities that are\nknown but have not been implemented because of the saturation of SELDADS I.\nPhase III software will begin the implementation of new forecast techniques\nsuch as models. Phase I software will take most of the effort in FY 1985;\na beginning of Phase II will occur later in the year. Phase I is expected to\nbe completed early in 1986 and major effort will then shift to Phases II\nand III.\n226","COOPERATIVE INSTITUTES\nDirector\nO/P\nDep. Director\nCooperative\nESG\nInstitutes\nCRP WRP PROFS WMP\nAL\nSEL\nAOML\nPMEL\nGLERL\nGFDL\nNSSL\nWPL\nARL\nSeveral Environmental Research Laboratories interact with the university\ncommunity through cooperative institutes. These institutes provide a mecha-\nnism for research collaboration and training in areas of mutual interest to\nNOAA and the academic community. There are six of these institutes at uni-\nversities in Colorado, Washington, Hawaii, Oklahoma, and Florida; each is\nclosely associated with one or more of NOAA's Environmental Research Labora-\ntories.\nCIMAS\nThe Cooperative Institute for Marine and Atmospheric Studies (CIMAS) is a\njoint research effort of NOAA and the University of Miami's Rosenstiel School\nof Marine and Atmospheric Science (RSMAS). The three research themes of CIMAS\nare Climate Variability, Ecosystem Dynamics, and 0cean-Seafloor Hydrothermal\nInteractions.\nThe CIMAS staff includes eleven Fellows who are appointed from RSMAS\nfaculty and NOAA staff in Miami and who conduct collaborative research. Also\nincluded in FY 1984 were three Members, four Associate Scientists, six Research\nAssociates, one Postdoctoral Associate, and three graduate students. Members\nCIMAS\nof the staff are stationed variously at the CIMAS building, the RSMAS campus,\nand NOAA laboratories. CIMAS further supports NOAA activities through the\nvisiting scientist program, which brought eleven scientists to the Miami com-\nmunity in FY 1984 to provide 19 lectures and 17 man-months of collaborative\nresearch.\n227","Accomplishments FY 1984\nCLIMATE VARIABILITY\nResearch on climate variability concerned Subtropical Atlantic Climate\nStudies (STACS), Equatorial Pacific Ocean Climate Studies (EPOCS), atmospheric\ncarbon dioxide (CO2) loading, and hurricane modeling.\nBoth theoretical models and field measurements indicate the Florida\nStraits as a critical monitoring point for determining the northward transport\nof mass and heat in the North Atlantic. CIMAS research efforts are directed\ntoward understanding the effects of local forcing by the curl of the wind\nstress over the Gulf of Mexico and Caribbean Sea on the transport at the\nFlorida Straits and the implications this might have on the interpretation of\nthe routes by which heat is transported northward by the ocean.\nIn the previous year we discovered a strong correlation between the curl\nof the wind stress over the Cayman basin in the western Caribbean and the sea-\nsonal cycle in the transport at the Florida Straits suggesting that the season-\nal transport is locally forced. This raised two questions: Why are there\nlarge values of the curl of the wind stress over the Caribbean? Also, if the\nseasonal transport is the result of local forcing, then by continuity a stor-\nage of fluid in the Caribbean is expected; why is there no indication in field\nmeasurements that such storage occurs? To answer the first question, the\nannual mean and annual cycle of the stress and stress curl over the Gulf of\nMexico and Caribbean Sea were documented. They show that large values of the\ncurl of the wind stress are due to the funneling effects on the trade winds by\nthe mountains on Hispaniola and the north coast of South America. To answer\nthe second question, a linear barotropic analytic model was developed for the\nCayman basin. The results indicate that because the model is barotropic, the\nbasin adjusts to the forcing nearly instantaneously. Very little storage of\nfluid occurs because the basin is open at its eastern boundary through the\nWindward Passage. This latter result has yet to be substantiated with field\ndata (see below) but, if confirmed, indicates that the Windward Passage is a\ncrucial monitoring point to understand the dynamics of the system.\nEfforts have also been directed toward understanding the dynamics of the\ncombined effects of the Caribbean Sea's island chain and the local forcing by\nthe annual mean curl of the wind stress. To this end a series of linear equi-\nvalent barotropic models has been developed in which the island chain is\nmodeled as a barrier. The results indicate that the system's pressure gra-\ndients adjust so as to generate a counterclockwise circulation around the bar-\nrier. These pressure gradients oppose the formation of an intense western\nboundary current on the North Atlantic side of the barrier. These preliminary\nresults are intriguing because they suggest a reason why field measurements do\nnot show an intense Antilles current on the North Atlantic side of the island\nchain.\nTwo cruises were successfully completed to the STACS experiment site at\n27°N between Florida and the Bahamas this summer, one on RSMAS ORV Calanus in\nJune and one on RSMAS ORV Cape Florida in July. During these cruises more\nthan 100 vertical profiles of current and temperatures across the Straits of\nFlorida were obtained. These data are now being analyzed together with results\nof previous cruises to accomplish one of the stated aims of the STACS experi-\n228","ment -- to determine methods to monitor efficiently the heat and mass trans-\nport by the Florida Current on an inter-annual basis.\nIn support of EPOCS, a comprehensive study of the energetic mesoscale\neddies (long waves) that appear annually (except during ENSO events) at the\nboundary between the South Equatorial Current and North Equatorial Counter-\ncurrent was completed. In addition, a large-scale surface current climatology\nfor the Equatorial Pacific has been computed from the drifting buoy data.\nThis will be an invaluable tool for determining surface current anomalies,\nboth for research studies of the 1982-83 El Niño and for future real-time\nmonitoring efforts.\nA new Postdoctoral Associate began EPOCS-related research that applies\nempirical orthogonal function and complex demodulation techniques to the EPOCS\ncurrent meter data to look at the vertical mode structures for the weekly to\nmonthly periods.\nContinued research using a time-dependent model shows that significant\nperturbations in the oceanic carbon cycle can occur on time scales of hundreds\nof years. This is significant because recently it has been shown from ice\ncore data that fluctuations in the atmospheric CO2 level have occurred on simi-\nlar time scales. Furthermore, recent oxygen isotope data have shown that these\nCO2 fluctuations led rather than lagged climate fluctuations, which implies\nthat marine carbon cycles may be forcing climatic changes. The model results\nwere presented at the Chapman Conference on Natural Variations in Carbon Diox-\nide and the Carbon Cycle in early January 1984.\nAtmospheric variation in CO2 is greatest over the Arctic's marginal ice\nzone (MIZ). Ocean processes research at the MIZ was conducted under the Navy-\nsponsored Marginal Ice Zone Experiment (MIZEX) in the Fram Strait. Final\nplanning of this experiment was completed at Pigeon Key, Fla., at a meeting\nhosted by RSMAS and CIMAS. A cruise was mounted during June and July on R/V\nPolar Queen. Cyclesonde automatic profiling current meters (CTD's) were sus-\npended from ice floes to document the temperature, salinity, and current struc-\nture under the ice edge. Here colder, fresher, surface water and ice from the\nArctic Ocean move south along the coast of Greenland above the halocline and\nwarmer, saltier North Atlantic water slides into the Arctic Ocean under a\nstrong halocline. The position of the ice edge and the budgets of ice, heat,\nand salt are thought to play an important role in worldwide climate vari-\nability.\nThe development and testing of the quasi-spectral hurricane prediction\nmodel using nested grids was continued during FY 1984. Numerical experiments\ntesting the effectiveness of spatially variable filters in controlling short-\nwavelength noise were carrier out. In the experiments we propagate the main\nsignal across mesh interfaces from regions of high spatial resolution into\nregions of lower resolution, in order to study the effects of these filters on\nCIMAS\nslow-moving (advective) signals and fast-moving (gravity wave) signals. Upon\ncompletion of these experiments, which used a one-dimensional version of the\nmodel, the two-dimensional version was restructured to utilize these filters\nand also to facilitate the introduction of movable meshes into the model.\nAfter the new spatial filters were introduced, a few moving-vortex experiments\nwere carried out so that the predicted wind fields could be compared with those\nobtained earlier using space-independent filters. Current effort is being\n229","directed toward producing useful graphical output of the model results in the\nform of three-dimensional surface plots, contour maps, and field profiles.\nECOSYSTEMDYNAMICS\nUnderstanding the causal mechanisms of fish stock variability is the pri-\nmary objective of CIMAS ecosystem dynamics research. Efforts are focused on\nfishes' early life-history stages and on survival and dispersion caused by\nphysical, chemical, and biological oceanic processes. Research on the dynamics\nof coral reef fish also continued in FY 1984.\nComprehensive larval fish surveys have been conducted in the Gulf of\nMexico since 1982. The results of the 1982 survey were compiled and published\nin 1984. Acquisition of data on larval distribution and abundances of the\nfamilies Lutjanidae (snappers) and Serranidae (groupers) was completed. These\ndata will be related to data on the physical environment in an effort to deter-\nmine those processes important to snapper/grouper larval ecology. In addition,\nthe research on the contribution of Gulf Stream meanders to the variability in\nshort-term catch rates and annual production of vermilion snapper in the South\nAtlantic Bight was completed.\nCIMAS participated in the successful atmospheric and ocean sampling for\nvolatile organic compounds over the equatorial Pacific along 150°W longitude\nfrom 20°N to 15°S. Sea water and sea surface air samples were simultaneously\ncollected aboard the NOAA R/V Researcher. Knowing the identities and distribu-\ntion of naturally occurring volatile organic compounds in the remote equatorial\nPacific, far removed from any human sources, will result in an understanding\nof the contribution of the marine system to global acid rain and infrared ab-\nsorption. Since air and seawater samples were collected simultaneously, flux\ndeterminations will be possible. Synoptic measurements of ozone concentration\nand ultraviolet and infrared irradiance were also collected.\nResearch on the effects of protogynic hermaphroditic reproduction common\nto coral reef fishes, especially groupers, was nearly completed in FY 1984.\nA\ngeneral mathematical model of this reproductive strategy was completed, and\nthe effects of exploitation were simulated. In both static and dynamic studies\nit was found that protogynic hermaphroditic reproduction was a more resilient\nreproductive strategy then dioecious reproduction under the assumption that\nmating is non-random. The reverse is true under random mating patterns.\nThese results are a first step in developing a general management strategy for\nimportant reef fish populations.\nThe field work for ecological studies involving microhabitat distributions\nof coral reef fishes within the Looe Key National Marine Sanctuary were com-\npleted in FY 1984. The distributions of 158 species were measured in 9 habi-\ntat zones within the Sanctuary. Analyses of these data will provide informa-\ntion on the community dynamics of reef fishes, the second step in developing a\ngeneral management strategy.\nThe second Southeast Stock Assessment Workshop sponsored by NOAA coopera-\ntively with CIMAS was held June 4-8, 1984. The objectives of the Workshop\nwere to (1) provide current management advice; (2) provide a timely forum for\ncritical review of assessment research; (3) provide direction for future re-\n230","search; and (4) promote scientific interchange between researchers. The Work-\nshop was attended by more than 50 scientists representing CIMAS; NOAA's South-\neast, Northeast, and Southwest Fisheries Centers; state agencies of the\nsoutheast United States, Puerto Rico, and the Virgin Islands; the Gulf of\nMexico, South Atlantic, and Caribbean Fishery Management Councils; and various\nacademic institutions. Sixty stock assessment reports and documents were in-\ncorporated into the Workshop Report.\nOCEAN-SEAFLOOR HYDROTHERMAL INTERACTIONS\nThis research theme was approved for CIMAS during FY 1984. Efforts were\nbegun to plan the modeling of the physical dynamics of sea floor vent plumes.\nPlans FY 1985\nCLIMATE VARIABILITY\nResearch on ocean-related aspects of climate will continue in FY 1985 in\nsupport of STACS, EPOCS, CO2 loading, and hurricane modeling. An increase in\natmospheric research contributions is planned through the addition of several\nnew Fellows. Five visiting scientists will provide 6 man-months of complemen-\ntary research.\nIn support of STACS, efforts will be directed toward determining the in-\nfluence that the Gulf of Mexico and Caribbean Sea have on the poleward trans-\nport of heat in the North Atlantic. The seasonable variability at the Wind-\nward Passage will be investigated to substantiate the FY 1984 model results.\nThe dynamics of the response of the eastern Caribbean to the seasonal\nforcing will also be investigated. The approach will be to utilize field data\nto test a linear equivalent barotropic model of the basin's response to the\nseasonal forcing. If necessary, a two-layer model will be developed. A pre-\nliminary analysis of the field data suggests that during autumn an along-\nchannel pressure gradient develops to oppose inflow into the Caribbean at the\nLesser Antilles. Confirmation of the process will be an important step toward\nunderstanding the adjustment of the North Atlantic to forcing by the trade\nwinds. The analysis will also provide information crucial to the design of\nfield experiments to monitor the northward heat transport through the region\nby the western boundary current regime.\nThe investigation of models of the combined effects of topography and\nforcing by the wind stress curl will continue. Here the focus is to determine\nthe pressure gradients set up by the model system. This will facilitate the\ndesign of field experiments and the interpretation of the complex numerical\nCIMAS\nmodels that are being developed for the region.\nAnalysis of the data collected on 15 research cruises in the Florida\nStraits will be completed in FY 1985. A free-falling current probe (Pegasus)\nsection northeast of Grand Bahama Island will be established, and another\ncruise of the ORV Calanus is planned to determine to what extent flow in the\nimmediate vicinity of the Bahamas contributes to Gulf Stream development. We\n231","are especially interested in understanding increases in mass and heat\ntransport north and east of the Bahamas.\nEmpirical orthogonal function and complex demodulation techniques will be\napplied to the EPOCS current meter data to look at the vertical mode struc-\ntures for weekly and monthly periods. Also, analyses of the EPOCS drifting-\nbuoy data sets collected before, during, and after the 1982/83 El Niño will be\nconducted using similar techniques.\nWork on the modeling of marine chemical cycles relative to atmospheric\nCO2 loading will continue with emphasis on (1) the forcing of atmospheric CO2\nfluctuation by perturbations in the ocean's nutrient cycle and hence the car-\nbon cycle with applications to glacial-interglacial transitions, and (2) the\noccurrence of anoxia. Participation in MIZEX will also continue.\nFor hurricane modeling in FY 1985, a series of barotropic prediction cal-\nculations is planned, including a moving vortex with free pressure surface,\nbarotropic prediction of synoptic fields, and beta effect studies. The latter\nstudies will require the use of movable inner meshes, and this extension to\nthe model will be implemented in the near future.\nECOSYSTEM DYNAMICS\nResearch on reef fish reproductive strategy and community dynamics re-\nlated to exploitation will be completed in FY 1985. Modeling recruitment pat-\nterns of reef fish larvae to the reef tract of the Florida Keys will be initi-\nated along with studies on the hydromechanics of marine fish larvae. Research\non the relation between climate variability and recruitment variability will\nbe undertaken with the addition of a new Postdoctoral Associate. Five\nvisiting scientists are scheduled to provide 3 man-months of collaborative\nresearch.\nOther biological elements of the predator-prey web involving larval fishes\nwill be investigated through collaborative research applying innovative sam-\npling technologies. At least three cruises are planned for 1985. The first,\non the ORV Calanus, will be in the Florida Straits for the purposes of testing\ndesign modifications and additions to a plankton camera. The second two, on\nthe ORV Cape Florida, will be for the purpose of working with an acoustic pro-\nfiling system (in collaboration with its developers), as well as with the\nplankton camera, to examine the fine-scale vertical distribution and interac-\ntions of zooplankton populations in the Gulf Stream.\nResearch on volatile organic compounds in the equatorial Pacific will\ncontinue with analyses of the samples collected during FY 1984. These samples\nwill be analyzed with a gas chromatograph/mass spectrometer.\nOCEAN-SEAFLOOR HYDROTHERMAL INTERACTIONS\nResearch will focus on initial modeling of the physical dynamics of the\nconvective plumes of sea floor hydrothermal vents. Planning will concentrate\non a field program to make field measurements of the model's parameters and to\ninvestigate the biological processes associated with the vent field.\n232","CIMMS\nThe Cooperative Institute for Mesoscale Meteorological Studies (CIMMS) is\na joint venture of the University of Oklahoma (OU) and ERL through the\nNational Severe Storms Laboratory. CIMMS received first funding in late FY\n1978 and began major efforts during FY 1979. The program objectives and\nactivities of CIMMS complement and supplement those of NSSL and the University\nthrough research conducted by Visiting Fellows, NOAA, and University staff,\nand student appointees. The present council of Fellows, which helps formulate\npolicy, includes two members from NSSL, both of whom hold adjunct professorial\nappointments at OU, and two members from OU. The Advisory Council, which\nincludes representatives from OU, NOAA, and outside organizations, meets\nannually.\nDuring 1984 CIMMS was host to researchers from China, South Africa,\nJapan, and France who undertook studies in mesoscale meteorological models and\ndevelopment of optimization analysis in Doppler radar meteorology. A CIMMS\nresearch scientist has continued his work on the Alpine Experiment and\nsatellite-based analysis techniques. In March 1984 he traveled to China to\npresent a paper at the International Symposium on Tibetan Plateau and Mountain\nMeteorology held in Beijing. Another CIMMS scientist developed a mesoscale\nvariational temperature analysis scheme and tested this scheme using the CIMMS\nMesoscale Model. This research was performed under a NASA contract, and the\nresults were presented in April 1984 at the NASA Goddard Space Flight Center\nProgram Review. A CIMMS scientist developed a variational optimization method\nto obtain two-dimensional wind field information from single-Doppler radar\ndata. Approximately 14 students employed by CIMMS are engaged in research\nstudies toward advanced degrees; 4 are undergraduate students. A CIMMS\nResearch Associate worked in the NEXRAD program. Three postdoctoral Fellows\non multiyear appointments work in cloud physics, mesoscale modeling, mesoscale\ndynamics, and convective instability.\nCIMMS research results were reported in approximately 10 reports and\npublications during FY 1984.\nConstruction of new facilities for CIMMS and the School of Meteorology in\nthe OU College of Geosciences is still an ongoing project.\nIn 1985 CIMMS will be host to a NEXRAD Conference in Norman on 2-4 April,\nand to the \"International Symposium on Variational Methods in Geosciences\" in\nSeptember.\nCIRA\nCIMMS\nThe Cooperative Institute for Research in the Atmosphere (CIRA),\nCIRA\nestablished September 1980, is jointly sponsored by Colorado State University\n(CSU) and NOAA and has close relationships with ERL in Boulder and NESDIS in\nSuitland, Md.\n233","The Institute's research has concentrated on global climate dynamics,\nlocal-area weather forecasting, severe storms, and the application to climate\nstudies of satellite observations. In addition, the Institute and National\nPark Service cooperate in air quality research. CIRA is playing a major role\nin the NOAA-coordinated U.S. participation in the International Satellite\nCloud Climatology Project (part of the Climate Research Program), and we plan\nincreased involvement in studies of the El Niño/Southern Oscillation\nphenomenon and other climate research and applications projects.\nFive NESDIS scientists in residence at CSU constitute the Regional and\nMesoscale Meteorology Branch of the NESDIS Development Laboratory. They lead\nthe CIRA collaboration with ERL in short-range weather forecasting research.\nThe CSU departments currently engaged in CIRA research are Atmospheric\nScience, Statistics, Psychology, Civil Engineering, Electrical Engineering,\nand Recreation Resources. Currently 28 separate research projects have been\nfunded through CIRA, including an IPA (Intergovernmental Personnel Act) with\nthe National Weather Service. CIRA personnel consist of 15 Fellows, 1 Post-\ndoctoral Fellow, 5 Visiting Fellows, 9 Research Associates, 2 Visiting\nScientists, and a Director. During FY 1984, five Graduate Research Assistants\nreceived degrees--three M.S. and two Ph.D. Each year the Visiting Fellows\nProgram provides the opportunity for independent research at CSU in\ncollaboration with NOAA scientists. A \"co-op\" program allows CSU graduate\nstudents to work in residence at NOAA Laboratories. A workshop entitled\n\"Research on Weather and Climate Applications at Colorado State University\"\nwas held at the Pingree Park Campus in September 1984.\nPlans include continued collaboration of NOAA and CSU scientists and\nstudents in research related to NOAA's mission within the special themes of\nCIRA, expansion of the Visiting Fellows Program, and continued development of\nresearch involving NOAA and CSU scientists with other agencies.\nA workshop on \"Agricultural and Forest Meteorology\" is planned for this\nfall. This workshop will facilitate interaction among participants from\nvarious departments of CSU.\nIn April 1985, CIRA will act as host of a workshop entitled \"Cloud Top\nBoundary Layer\" sponsored by the World Meteorological Organization.\nApproximately 40 scientists from throughout the world will participate.\nCIRES\nThe Cooperative Institute for Research in Environmental Sciences (CIRES)\nis jointly sponsored by the University of Colorado and ERL and receives a\nroughly equivalent amount of support from other public and private sources.\nCIRES Fellows have academic affiliations with eight departments at the Univer-\nsity of Colorado: Chemistry, Chemical Engineering, Physics, Geography, Geolog-\nical Sciences, Electrical Engineering, Mechanical Engineering, and Astrophys-\nical, Planetary, and Atmospheric Sciences. Current research in CIRES is in\nthree broad areas: Environmental Chemistry, Atmospheric and Climate Dynamics,\nand Geodesy and Solid Earth Geophysics.\n234","ENVIRONMENTAL CHEMISTRY\nThe areas of research include environmental analysis, reaction kinetics,\nmolecular biology, surface science, and analytical instrumentation. Environ-\nmental applications include such diverse subjects as acid rain, air and water\npollution associated with energy development, climate change resulting from\ncarbon dioxide emissions from fossil fuel burning and other pollutants, strato-\nspheric ozone depletion, improvements in catalyst technology, fuel additives\nto improve efficiency of combustion and decrease pollutant emissions, photo-\nchemical oxidant formation in the troposphere, use of microorganisms to\ndetoxify chemical waste, earthquake hazard evaluation based on gaseous emis-\nsions from the ground, protection of crops against frost, marine measurements\nof chlorofluoromethanes as transient tracers of ocean circulation and global\nuptake of pollutants by the sea, and evaluation of the atmospheric consequences\nof nuclear warfare.\nAccomplishments FY 1984\nOf the many areas of active research in environmental chemistry, we high-\nlight recent and ongoing work on the environmental effects of nuclear war.\nThe climatic and other long-term effects of nuclear war are of immense impor-\ntance to defense planning of our country. It is expected that in the near\nfuture NOAA will play a lead role in further evaluating the consequences of\nnuclear war, especially the effects on the atmosphere and climate. CIRES work\nin such evaluation illustrates the type of interdisciplinary research that is\nmade possible through cooperative institutes where scientists from a broad\nrange of disciplines can work together on problems that cannot be approached\nfrom any single research perspective.\nThe discovery of the long-overlooked climatic effect now know as \"nuclear\nwinter\" was made in a collaborative research effort by a CIRES Fellow and the\nDirector of the Max Planck Institute for Chemistry in Mainz, West Germany, and\nfirst published in a Swedish environmental journal in June 1982. The original\nwork has since been expanded by the authors as well as by numerous scientists\nin both university and government laboratories. Briefly, the large quantities\nof smoke aerosol produced by thousands of fires in forests, industry, and\nurban areas would be sufficient to absorb most of the solar radiation incident\non the Earth's atmosphere throughout most of the Northern Hemisphere. The\nblockage of sunlight from reaching the surface would result in cooling of\nmidcontinent temperatures by as much as a few tens of degrees centigrade.\nBecause of the large heat capacity of the mixed layer, ocean temperatures\nwould be little changed, and the relatively warm ocean air would partially\nameliorate the temperature effect near coastlines. The highly perturbed\natmosphere would be characterized by a strong temperature inversion, and the\nnormal separation between troposphere and stratosphere would no longer be well\ndefined; the residence time of the smoke aerosol in such an atmosphere might\nbe considerably enhanced. In any case, it is expected that the low\ntemperatures resulting from a nuclear winter would persist for at least a few\nCIRES\nweeks and possibly several months. Recent work by investigators at the\nNational Center for Atmospheric Research (NCAR) has shown that a homogeneous\nblack cloud would not be necessary to produce these effects; a black patch of\ncontinent size passing over a land area for only 2 days could result in a\n\"quick freeze\" with comparable biological consequences.\n235","Plans FY 1985\nContinuing research is aimed at reducing the very large uncertainties\nassociated with these effects. To name a few, these uncertainties include the\namounts and size distribution of smoke aerosol produced in the various types\nof fires, the optical properties of the aerosol, the scavenging of aerosol by\nprecipitation events, and the response of the Earth-atmosphere system to such\na large perturbation in its heat balance. Other work is aimed at evaluating\nthe effects on the postwar environment of the large numbers of different\npyrotoxins produced in the nuclear war fires.\nATMOSPHERIC AND CLIMATE DYNAMICS\nResearch focuses on elucidating and describing various aspects of the\nfundamental processes of the atmosphere, oceans, and cryosphere as interactive\nmedia. The effort at CIRES is an interplay between theoretical and observa-\ntional studies. Reflecting the wide range of topics involved, the research\ndone by this group is quite diversified and falls into three broad categories:\nstudies of long-time-scale climate variability as affected by continental\nconfigurations and ice sheet dynamics; studies of secular time-scale\nvariability, for which historical and contemporary climate records offer an\nobservational data base; and studies of processes that are relevant to under-\nstanding both climate variability and its real-time component, weather.\nMajor segments of the CIRES work relating to Climate Analysis and Climate\nModeling are performed as part of ERL's Climate Research Program. Other compo-\nnents of the Atmospheric & Climate Dynamics program, supported independently,\nare described below.\nAccomplishments FY 1984\nATMOSPHERE-OCEAN INTERACTION\nThe coupling of the atmosphere and ocean at the sea surface and its role\nin weather and climate is one of the most important and least understood prob-\nlems of atmospheric and climate dynamics. CIRES research includes investiga-\ntions into boundary layer adjustment processes, in both media, singly and\ninteractively, and climatological aspects of the coupling on large scales.\nModeling and analysis of the mechanics of the stratocumulus-topped marine\nboundary layer using data gathered under the auspices of NOAA's Equatorial\nPacific Ocean Climate Studies program has placed emphasis on the transition\nfrom solid stratocumulus to broken trade cumulus and its climatological\nimplications. Although the mechanics can be interpreted consistently using\nrelatively simple modeling techniques, processes traditionally thought to be\nunimportant (such as the diurnal cycle) are in fact sometimes dominant. Marine\nstratocumulus occurs not only in the subtropics east of the major continents,\nassociated with coastal upwelling, but also, as a result of cold, continental\nair outbreaks, over the western oceans. A climatological study of cold air\noutbreaks and resulting marine cyclogenesis off the east coast of Asia suggests\n236","that north-south sea-surface temperature gradients are a critical aspect of\nair-sea interaction and that the interannual variability of the frequency of\nthis cyclogenesis is influenced significantly by large-scale variability asso-\nciated with the El Nino/Southern Oscillation (ENSO) phenomenon. A study of\nthe climatology of the Ekman convergence in the subtropical Pacific Ocean has\nshown that the poleward heat fluxes due to these processes contribute signifi-\ncantly to the total flux and are probably of major importance to the ENSO\nproblem.\nCRYOSPHERE-CLIMATE INTERACTION\nInteractions between polar sea ice, snow cover, and climate have been the\nmain focus of recent work. Satellite and synoptic data are being used to\nanalyze relationships between cloud cover and Arctic ice. A classification of\ndaily 700-mb circulation patterns has been prepared, and the distribution of\ncloud within high-latitude synoptic systems is being determined for comparison\nwith outputs from the Goddard Institute of Space Sciences (GISS) general circu-\nlation model. A project to map the seasonal progression of surface melt in\nthe Arctic from high-resolution DMSP imagery has begun. -ice data provided\nby the NASA Scanning Multifrequency Microwave Radiometer (SMMR) sensor have\nbeen assessed. A Department of Energy project is continuing to assess the\nvariability of lake freeze-up/break data from Canada and Finland in relation\nto climatic factors, as a guide to possible CO2-induced warming effects.\nCIRES also operates the World Data Center-A (WDC-A) for Glaciology (Snow\nand Ice) and the associated National Snow and Ice Data Center. Base funding\nis provided by NOAA's National Environmental Satellite, Data, and Information\nService; DOE, NASA, NOAA, and the Office of Naval Research provide additional\ncontractual support. WDC-A maintains data archives on snow cover, sea ice,\nice cores, ice sheet radio-echo soundings, and Great Lakes ice. It has large\ncollections of global Defense Meteorological Satellite Program imagery, glacier\nphotographs, and glaciological literature. Data management services are being\nprovided for the Marginal Ice Zone Experiment (MIZEX) project.\nPALEOCLIMATOLOGY-PALEOCEANOGRAPHY\nWork continues on understanding how past global climate has changed, and\nin particular to investigate hydrological interactions with the ocean circula-\ntion, especially vertical mixing and organic carbon sedimentation. Continental\npaleotopography is being reconstructed, and atmospheric circulation for dif-\nferent hypothetical continent configurations is being modeled with the Com-\nmunity Climate Model in collaboration with NCAR scientists.\nATMOSPHERIC DYNAMICS IN COMPLEX GEOMETRY\nWork is concentrated on atmospheric wave motions and turbulence. Experi-\nmental work with clear-air Doppler radars aids in our understanding of atmo-\nspheric flows and transport over complex terrain and computer-aided analysis\nCIRES\nof viscous flows and/or transport problems in engineering science. The two\nare intimately connected since the atmospheric flow models are nonhydrostatic.\n237","One continuing study focuses on the development of a nonhydrostatic,\nBoussinesq algorithm for the numerical simulation of small-scale atmospheric\nflows over complex terrain, for environmental and energy-related studies rang-\ning from pollutant transport and dispersal to siting studies for potential\nwind power applications.\nA second activity is seeking to develop improved algorithms for numerical\nsimulation of incompressible flow in computer-aided design. These are being\napplied to the study of physical instabilities, free and/or moving surface\nproblems that arise in many industrial applications, and flow of stratified\nfluids in complex geometries.\nWork is also in progress on flow and stability problems related to manu-\nfacturing in space, in cooperation with scientists at NASA Lewis Laboratory\nand scientists in Lyon, France, in preparation for Shuttle experiments.\nWAVE DYNAMICS\nA quasi-linear time-dependent model has been developed in collaboration\nwith scientists at NOAA and NCAR. This model incorporates interactions among\nthe mean atmospheric circulation, planetary waves, chemistry, and radiation.\nThe model will be used to study various dynamical and transport problems in\nthe stratosphere and mesosphere.\nAnother modeling effort is addressing the problem of tidal variability.\nSimulation studies of meteor echo returns have been performed to determine\nwhether the observed tidal variability is due to noise or geophysical events.\nThe results indicate that a portion of the variance of tidal amplitudes and\nphases can be attributed to incoherent noises. However, this variance gener-\nates random amplitude and phase changes whereas the observed variability shows\nprogressive systematic changes.\nIn another project, we are examining clear-air Doppler radar data for\ngravity wave and tidal momentum fluxes. These fluxes are important for deter-\nmining the frictional drag in the atmosphere. A method for determining the\nspectral content of the momentum flux was developed.\nPlans FY 1985\nATMOSPHERE-OCEAN INTERACTION\nInitiation of a major field research program with partial funding from\nNOAA/ERL, to investigate the causes of variability of stratocumulus\nclouds over the Pacific off the coast of California. This will be highly\nrelevant to the interagency First International Satellite Cloud\nClimatology Regional Experiment.\nDevelopment of a mixed-layer upper boundary condition for isentropic\nmodels of the large-scale ocean circulation systems and use of the\nresulting coupled model to study the dynamics of the subtropical\nconvergence.\n238","Modeling studies, in collaboration with NCAR scientists, of the role that\na parameterization of stratus and stratocumulus clouds would play in a\ngeneral circulation model's climate.\nPlanning for future exchange visitors to pursue the studies of the\nconnection between ENSO and Asian climate and for execution of the field\nphase of the Frontal Air-Sea Interaction Experiment in early FY 1986.\nCRYOSPHERE-CLIMATE INTERACTION\nAnalysis of cloudiness computed by the GISS GCM for a control experiment\nwill be analyzed and compared with observed summer conditions.\nThe NSIDC/WDC-A for glaciology will install a VAX-750 and prepare to\nimplement software developed at JPL to process microwave data on sea ice\nconditions (NASA funding). A DoD-funded image display and analysis\nsystem will also be installed.\nWAVE DYNAMICS\nResults from the coupled dynamical-chemical model will be analyzed.\nParticular emphasis will be placed on the planetary wave transport of nitric\noxide and its relationship to the sporadic winter anomaly. The question of\ntidal variability will be further addressed. We intend to develop a simple\nmodel to test gravity wave and tidal interaction, and determine the tidal\nstructure from wind data.\nAnalysis of spectral information of the momentum flux will continue,\nespecially focusing on the tropospheric generation of energy and the\ndeposition of momentum due to the breakdown of gravity waves and tides.\nA\nfield experiment will be conducted at Jicamarca, Peru, to study breaking tides\nin the equatorial region.\nSOLID-EARTH GEOPHYSICS\nSolid-earth geophysics continues to be one of the principal themes of\nCIRES research, although most support program support is obtained from sources\nother than NOAA/ERL (USGS, NSF, NASA, DOD, etc.). Some of the CIRES research\non geodesy is now supported by the National Geodetic Survey. The NOAA National\nGeophysical Data Center also provides support and an important point of inter-\naction between CIRES and NOAA scientists.\nThe current program concerns geodesy, observational and theoretical\nseismology, geodynamics (crustal deformation using modern geodetic techniques),\nengineering seismology, and laboratory studies of rock failure and rock prop-\nerties under high stresses.\nCIRES\n239","Accomplishments FY 1984\nThe location of a magnitude 5.8 earthquake near Adak Island, Alaska, was\npredicted months in advance of the event on the basis of data provided by the\nCIRES Adak Seismic Network and prediction concepts and approaches developed by\nCIRES researchers. Although no basis for fixing the time has been developed,\nthe identification of the locations with high precision gives convincing evi-\ndence of progress in understanding the seismotectonics of subduction zone\nearthquakes. A specific forecast of a large earthquake in the region of Adak\nCanyon before October 1985 has been made public, as a test of the hypothesis\nof precursory quiescence.\nCIRES has pioneered in research on seismic quiescence as a precursor to\nlarge earthquakes. Detailed studies during the past year of seismicity pat-\nterns in southern California and Hawaii have produced additional results on\nthe diagnostic value of such studies, as well as new insights into the problems\nusing routinely compiled data catalogs for this purpose. Studies of changes\nin inelastic attenuation of seismic waves prior to earthquakes have been car-\nried out for both the Aleutian Islands and Hawaii seismic zones.\nThe theoretical seismology program has continued to be concentrated on\nproblems of nuclear test monitoring. The power of the quasi-harmonic de-\nconvolution technique developed in CIRES has been demonstrated with additional\ncases, and important steps toward solving the remaining technical problems\nconfronting a comprehensive nuclear test ban treaty have been taken.\nThe analysis of sea-level data throughout Greece and the Greek islands\nhas been completed in the search for evidence of vertical crustal movements.\nThe results show that some islands are rising, some are subsiding, but on the\nwhole the region is more stable than had been thought. This research is part\nof a NASA-supported crustal dynamics project.\nStudies of seismic velocity anisotropy, a new initiative in CIRES during\nthe past few years, have resulted in a new mineralogical model of the upper\nmantle, in new results for the structure and properties of the crust and upper\nmantle under southeastern China, and acquisition of data on upper mantle\nseismic anisotropy under Tonga and Fiji. The Tonga-Fiji seismic network is\nsupported by NSF.\nThe geodynamics program has developed a variety of modern techniques to\ninvestigate local and regional deformation of the crust. Recently, the\nNational Geodetic Survey (NGS) entered into a cooperative agreement with CIRES,\nunder which geodynamics research through modern geodetic techniques should\nflourish. The NGS agreed to share the funding of a facility position through\nthe Physics Department and CIRES, and that faculty member was hired and began\nwork in 1983. Current CIRES research topics of importance to NGS include two-\nand three-color laser electronic distance measurement instruments, and Earth\nrotation parameters, including nutations, body and ocean tides, and changes in\nthe length of the day.\nCIRES is the focus of a major geodesy research program involving state-of-\nthe-art space technology. The University NAVSTAR Consortium, with the Univer-\nsity of Colorado, Columbia, Harvard, MIT, Princeton, CalTech, and the Univer-\nsity of Texas participating, will assemble, test, maintain, and use terminals\n240","for highly accurate relative positioning of satellites. The terminals will\nreceive signals from the NAVSTAR/Global Positioning System satellites to attain\n1-cm accuracy in three dimensions over baselines up to 100 km for a 3-h obser-\nvation. Global tectonic and earthquake problems will be addressed with this\nrevolutionary surveying technique. Other work in geodynamics includes studies\nof tectonic processes by monitoring random and magnetotelluric signals.\nResearch in engineering seismology has progressed in three different\ndirections. Hybrid numerical techniques have been developed to calculate the\nground motion amplifications due to local geology and topography. These tech-\nniques have been used to study surface motion amplifications due to subsurface\ncavities at different depths and of various shapes. The results have engineer-\ning applications also in ultrasonic nondistructive evaluation. A multiple\nscattering approach and averaging techniques have been used to study wave\npropagation in media with microstructures. Calculated effective wave speeds\nshow important/variations with porosity and distribution of microcracks. The\nthird area of study is the seismic response of long underground structures\nlike pipelines and tunnels. Our careful analysis of the interaction between\nthe structures and the surrounding ground has led to the identification of\nmost important parameters governing the response.\nResearch in rock mechanics has led to reliable techniques for locating\nincipient fault planes. Surface deformation measurements using optical holo-\ngraphy reveal an elongated bulge on the sample prior to failure. The fracture\noccurs along the long axis of the bulge. For constant strain rate S\nexperiments, in which a sample is axially compressed under confining pressure,\nthe bulge first appears at approximately 60% of the failure stress. During\ncreep experiments the bulge becomes visible during the secondary creep stage.\nAlthough surface deformation measurements clearly show the location of the\neventual fault plane, other techniques have been unable to indicate the loca-\ntion of the incipient fracture. Neither changes in elastic wave velocity and\nattenuation nor crack statistics obtained from scanning electon microscopy on\ndilatant samples are sensitive enough to reveal the incipient failure zone.\nThe development of a failure zone was studied by observing the time- and\nenvironment-dependent growth of single cracks in glass and of crack systems in\nrocks. In contrast to previous theory, present experimental data, derived\nfrom optical holography, microscopy, elastic wave velocity and attenuation\nmeasurements and the location of acoustic emissions, show the failure zone to\nbe very narrow and extending beyond the visible macrocrack tip.\nThrough the development of a new acoustic transducer with a flat\nfrequency response between 10 kHz and 6 MHz and a small (<100um) sensing area,\nit is now possible to study acoustic emissions from rock samples in the same\nmanner that earthquakes are studied by seismology. Starting, propagating, and\nstopping phases of single cracks have so far been recorded.\nPlans FY 1985\nCIRES\nEarthquake prediction research will continue along the same general lines,\nwith special attention to observations related to the accurately predicted\nearthquake near Adak Island. Further work on attenuation changes in Hawaii\nwill be completed. The multi-investigator, multi-national studies in Greece\nwill continue.\n241","Laboratory, theoretical, and field studies of seismic anisotropy will\ncontinue. Work on anisotropy under the Pacific basin will be done by a visit-\ning scientist from Japan. A Fulbright Fellow from Egypt is working on a seis-\nmotectonic map for the National Geophysical Data Center, NESDIS.\nIt is expected that the GPS program will expand considerably in the\nfuture. There is a vast field of opportunity for GPS measurements. NSF is\nprojecting to fund the consortium with approximately $5 million between now\nand 1990.\nWork on wave propagation in media with microstructures will be focused on\nthe effect of the properties of the interfaces between the micro-inclusions\nand the surrounding matrix on attenuation. Also anisotropy caused by oriented\ninclusions will be studied. The hybrid numerical technique will be extended\nto analyze wave scattering from near-surface cavities and cracks. This extend-\ned technique will be used to study also the three-dimensional response of\nstructure embedded close to the surface.\nThe new capability in microseismology will be used to study the elastic\nwave radiation from dynamic fractures in simple and complex materials. The\naim is to characterize both the nature of the dynamic failure and the medium\nthrough which the elastic waves propagate.\nWhole rock deformation and \"single crack\" propagation experiments will be\ncontinued with a view toward a better understanding of the failure process.\nVariables such as moisture content, rate of deformation, minerology, and grain\nsize will be considered and their effects isolated.\nA new project was initiated to determine the stresses in the mantle that\nare responsible for plate tectonics. The attenuation of seismic waves in the\nmantle is thought to be due to interaction of waves with dislocations in crys-\ntals. The equilibrium density of dislocations is a function of the applied\nstress and temperature. By measuring the attenuation of acoustic waves at\nseismic frequencies as a function of dislocation density and temperature in\nsingle crystals of olivine we expect to infer the stresses that exist in the\nmantle.\nJIMAR\nThe Joint Institute for Marine and Atmospheric Research (JIMAR) is\nlocated at the University of Hawaii. JIMAR was formed in FY 1978 in\nassociation with the University and PMEL. The principal research interests of\nJIMAR are climate, equatorial oceanography, and tsunamis.\nAccomplishments FY 1984\nCLIMATE RESEARCH\nUse of satellite observations for minitoring the trade winds is being\ninvestigated. The eastern Pacific trade wind indices derived from low-level\n242","satellite winds proved excellent monitors of the record-breaking 1982-83\nSouthern Oscillation. The negative phase began in early 1982, similar in\ntiming to previous strong oscillations, and in early 1983 reached maximum\nnegative values more than three times larger than those recorded during the\n1976-77 Southern Oscillation. However, this was not preceded by a strong\npositive phase as in previous oscillations. Although the equatorial easter-\nlies returned to above normal by mid-1983, the area index of the southeast\ntrades remained below normal throughout 1983. The strength of the trade winds\noff the Peruvian coast has trended downward for the past six years and\nremained at record low values throughout 1983.\nSurface winds obtained from satellite observations have been reduced to\nthe surface level on semimonthly and monthly time scales by use of a scheme\nbased on monthly climatological shears between the long-term means of ship\nwinds and Geophysical Operational Environmental Satellite (GOES) low-level\nwinds. These satellite winds are merged with ship winds and other\nconventional data to produce the monthly mean surface wind field over the\ntropical Pacific Ocean in support of climate research.\nEvaluation of a historical marine data set compiled from merchant ship\nweather observations is continuing, to determine its usefulness for\nidentifying secular changes in sea-air heat flux. These observations\nincorporate a variety of measurement errors and differing methods of\nobservation. Changes in tropical sea-air heat flux over the past 125 years\nmay not stand out above the general noise level, except possibly on heavily\ntraveled routes with many ship observations.\nComposite analysis has been completed of the vertical structure of the\nnear-equatorial convergence zone (CZ) for the Special Observing Periods 1 and\n2 of the First GARP Global Experiment (FGGE) Satellite photographs were used\nto locate the CZ and classify the intensity of convection within the CZ.\nOmega dropwindsondes provided the data for the vertical structure. Marked\nvariations in the vertical structure between the central and eastern Pacific\nregions were observed. A deep cool/dry band located between 130°W and 160°W,\nwhich penetrated from the surface to the upper troposphere, separated these\ndifferent regions. The cool/dry band appeared to be associated with persistent\ninteractions between the tropical and middle-latitude circulation in the\nregion.\nStudies of interactions between tropical and middle latitudes used the\nFGGE Omega dropwindsonde data set to investigate cirrus surges and the\nstructure of the nearby equatorial convergence zone. A weakening, and\nsometimes a complete breakdown, of the CZ was found east of cirrus surges\nassociated with these interactions. In addition, it was found that in many\ninstances the cirrus surges were not cumulonimbo-genetic but instead appeared\nto be the result of broadscale ascent of tropical air east of a penetrating\nsubtropical trough. The CZ at the \"root\" of the cirrus surge was notably\nlacking in cumulonimbi. A model for Southern Hemisphere interactions appeared\nuseful for understanding the mechanisms present during these interactions.\nJIMAR\nEQUATORIAL OCEANOGRAPHY\nPreliminary descriptive analysis and processing of the Line Islands\nprofiling data have been the main activities under the Pacific Equatorial\n243","Ocean Dynamics (PEQUOD) Program. One interesting qualitative result is that\nthe so-called \"deep jets\", the stack of alternately eastward and westward\ncurrents that are characteristic of the deep water near the Equator, have no\nperceptible vertical propagation over the period of observation of more than\n1 year. Their amplitude changes irregularly on a variety of time scales, but\nsome of the jets persist throughout the record. This appears to rule out the\nhypothesis that the jets are vertically propagating, linear, equatorially\ntrapped waves of annual or interannual period.\nAnalysis of the North Pacific Experiment (NORPAX) data has continued. A\nmajor effort has gone into the study of sampling and aliasing in the ship\nstation data. General techniques were developed for determining the errors in\nharmonic analysis of irregularly sampled data. It was found that the internal\nerror estimates from harmonic analysis using multiple linear regression tech-\nniques are generally underestimated by as much as a factor of 2. In the NORPAX\nTahiti Shuttle experiment, for most variables we found that no significant\ndifference can be distinguished between the two extreme longitudes of the ship\ntrack, 150°W and 158°W. To study the annual cycle, it is generally better to\nanalyze all sections together, without regard for longitude.\nSea level response in the equatorial Pacific during the 1982-83 El Niño\nwas analyzed. Evidence of equatorially trapped Kelvin waves of first and\nsecond baroclinic mode was found in calculated cross correlation functions.\nThese waves were apparently forced in the western Pacific by energetic westerly\nwind events. Complex empirical orthogonal function (EOF) analysis of sea\nlevel was begun.\nMeteorological data from the Line Island Profiling Program of PEQUOD were\nanalyzed to understand the linear warming trend in sea surface temperature\n(SST) at Jarvis Island during most of 1982. It was found that anomalous net\nheating of the sea surface could not explain the SST anomaly. Timing of\ncentral Pacific SST, sea level, wind, and surface current changes suggests a\nnonlocal cause for SST warming early in the 1982-83 El Niño. EOF decomposi-\ntion of time-latitude fields shows that simple advective balance held during\nthe early phase of the event. The conclusion is that pulse-like Kelvin waves\ndetected in earlier work were responsible.\nTheoretical studies of equatorial waves have continued. A study has been\ncompleted of the propagation of wind-driven Kelvin waves into the deep equa-\ntorial ocean in the presence of realistic background stratification. There is\na significant energy flux from the surface layer into the deep water in these\ncalculations. As of the end of FY 1984 there is no consensus among equatorial\nmodelers on this point, and further study and discussion are in order.\nTSUNAMI RESEARCH\nThe solid-state tsunami gage program, under National Science Foundation\nsponsorship, was completed through the lab test and field-deployable versions\nwith the final development of a 6-in-diameter lab test system and a 4-in field\ntest prototype. Both units performed successfully in the fast-sample mode\nneeded for tank tests. Recommendations for a final version were made.\nThe call-out procedure and tsunami observers' list for all islands was\nupdated. Trial time-lapse films were made by the new observers at sites on\n244","East Kauai and West Hawaii. Official permission was obtained from the National\nPark Service for a permanent camera installation at Kawaihae.\nThe Hawaii tsunami of 29 November 1975 was modeled, assuming a landslide\nfor the source. Three-dimensional calculations for solving the incompressible\nNavier-Stokes equations were performed on the Los Alamos CRAY computer. The\nobserved tsunami wave profile, which showed that near the source the second\nwave was larger than the first wave, was found to be inconsistent with a land-\nslide source model for the tsunami.\nThe Los Alamos shallow-water-wave computer program called SWAN was\nadapted for use on the University of Hawaii Harris computer. The program code\nwas used to study tsunami waves interacting with circular islands, triangular\nislands of dimensions characteristic of the island of Hawaii, and Hilo Bay.\nThe formation of tsunami waves from initial surface depressions or uplifts was\nstudied for a circular island and a triangular island for the May 1983 earth-\nquake in the Sea of Japan. The program was also used to study the wave inter-\naction in Waianae harbor (Oahu) to help local authorities improve the entrance\nwave interactions. The program code is being used by a University of Hawaii\ngraduate student to study the effect of tides on the Musi river in Indonesia.\nPlans FY 1985\nCLIMATE RESEARCH\nEvaluation of the marine data deck will continue, and it has been pro-\nposed to expand surface wind monitoring to cover the global tropics.\nThis is part of the TOGA (Tropical Oceans and Global Atmosphere) program.\nStudy of middle-latitude tropical interactions and their influence on\ntropical circulations and on El Niño/Southern Oscillation (ENSO) events\nwill continue. These investigations will include an analysis of extreme\nENSO events through use of satellite imagery and studies of tropical and\nmiddle-latitude interactions, a comparison between equatorial easterly\nand westerly winds and their attendant precipitation, and a characteriza-\ntion of the South Pacific Convergence Zone (SPCZ). Recent studies of the\nAustralian summer monsoons suggest a linkage among the monsoon, SPCZ, and\nSouthern Hemisphere extratropics.\nTwo TOGA data centers, one for sea level and the other for wind data,\nwill be located at JIMAR.\nThe sea level data center will produce monthly sea level anomaly maps for\nthe tropical Pacific in near real time (1 month delay). A similar\nproduct for the tropical Indian Ocean will be produced when an adequate\nnetwork is in place.\nEQUATORIAL OCEANOGRAPHY\nJIMAR\nPegasus data will be analyzed from PEQUOD.\n245","Shuttle data from 4°S to 10°N will be analyzed with emphasis on the mean\nand seasonal cycle.\nA 5-year study of seasonal and interannual variability of synoptic\noscillations in the central equatorial Pacific will be undertaken.\nA numerical model will be developed to study the effect of coastal\ngeometries on equatorial waves. There will also be work on an equatorial\nmodel forced by a meandering intertropical convergence zone (ITCZ) and\ninteractions of equatorial waves with mean flows.\nTSUNAMI RESEARCH\nResearch will continue on numerical studies of tsunami generation,\npropagation, and run-up.\nJISAO\nThe Joint Institute for Study of the Atmosphere and Ocean (JISAO) was\nformed in FY 1977 with the University of Washington. The main areas of\nemphasis within JISAO continue to be climate dynamics, estuarine processes,\nand environmental chemistry.\nAccomplishments FY 1984\nClimate\nJISAO has contributed to the Equatorial Pacific Ocean Climate Studies\n(EPOCS) and Tropical Oceans and Global Atmosphere (TOGA) research programs\ninvolving both observational and theoretical climate studies. An atlas consis-\nting of a series of time-lagged, seasonal correlation and regression charts\nand time series for El Niño events during the period 1950-80 has been\nprepared; it is based on the comprehensive set of marine surface observations\nproduced by the staff of CIRES. The same data set has also been analyzed with\na view toward apparent interdecadal trends in sea-surface temperature induced\nby changes in measurement techniques.\nThere is continuing analysis of hydrographic and current meter data from\nthe Hawaii-Tahiti Shuttle Experiment with the goal of documenting\nfinestructure variability in the upper equatorial Pacific Ocean. One\ncomponent of the study has been to develop a theory for the Equatorial\nSubsurface Countercurrents which are strong, subsurface eastward flows below\nthe thermocline in the Atlantic and Pacific. This work is the first\ncomprehensive theoretical treatment of these recently discovered currents in\nwhich their dynamics and relationship to the Equatorial Undercurrent are\nexplored.\n246","Another component of the theoretical studies involves examining wave/\nmean-flow interactions in an equatorial ocean model with emphasis initially on\nhow stable, low-frequency equatorial Kelvin and long Rossby waves are modified\nby realistic mean flows like the Equatorial Undercurrent.\nJISAO Senior Fellows have participated actively in the planning for the\nTOGA program at both the national and international level. In the area of\nplanetary wave/mean flow interaction, one Postdoctoral Fellow has been engaged\nin studying various aspects of translating Rossby wave critical layers to\nassess the effects of mean flow change on the dynamics of critical layers.\nENVIRONMENTAL CHEMISTRY\nJISAO is supporting postdoctoral research in trace element removal both\nin laboratory and in natural systems, and has played an active role during the\nPast two years in organizing the Environmental Chemistry activities at the\nUniversity of Washington. Environmental chemists are distributed among\ndepartments all over the university campus; this organization improves\ncommunication and helps focus their mutual research activities.\nPlans FY 1985\nJISAO has recently been designated an Experimental Climate Forecast\nCenter in the United States National Climate Program. The research of\nthe Center will involve the following themes in support of the\ndevelopment of a long-range forecasting capability: observational studies\ndesigned to complement the modeling activity; use of the Community\nClimate Model for sensitivity and predictability studies with emphasis on\ntropical sea-surface temperature anomalies; cooperation with NCAR and\nGFDL in aspects of model development such as the treatment of mountains;\nand diagnostics of dynamically based intermediate and long-range\noperational forecasts and extended runs of a global-circulation model.\nA high priority during FY 1985 will be to secure funding for the continu-\nation of the core program in Environmental Chemistry and to revive the\ncore program in estuaries, which has been dormant since 1981. In addi-\ntion, the Institute will explore the possibility of expanding activities\nin fisheries and marine biology, with emphasis on year-to-year variability\nin recruitment.\nJISAO\n247","","APPENDIX: Acronyms and Abbreviations\nACE\nArctic Cyclone Experiment\nADC\narea of deeper convection\nAFE\naverage forecast errors\nAutomation of Field Operations and Services (NWS)\nAFOS\nAGASP\nArctic Gas and Aerosol Sampling Program\nAirborne Investigations of Mesoscale Convective Systems\nAIMCS\nAeronomy Laboratory (ERL)\nAL\nALPEX\nALPine EXperiment\nAtlantic Oceanographic and Meteorological Laboratory (ERL)\nAOML\nAPEX\nArctic Polynya EXperiment\nAir Resources Laboratory (ERL)\nARL\nARTCC\nAir Route Traffic Control Center\nAtmospheric Studies in COmplex Terrain (DOE)\nASCOT\nASV\nanodic stripping voltammetry\nAtmospheric Turbulence and Diffusion Division (ARL)\nATDD\nAnalysis of the Tropical Ocean Lower Layer\nATOLL\nAdvanced Weather Interactive Processing System for the 1990's\nAWIPS-90\nAir Weather Service (USAF)\nAWS\nBoulder Atmospheric Observatory (ERL)\nBAO\nClimate Analysis Center (NMC)\nCAC\nCAMS\ncontrol and monitoring system\nCAPTEX\nCross-APpalachian Tracer EXperiment\nCBI\ncomputer-based instruction\nCESD\nComputer and Engineering Support and Development\nCG\ncloud to ground\nCHILL\nCHicago ILLinois\nCI-FA\nchemical ionization-flowing afterglow\nCooperative Institute for Marine and Atmospheric Studies\nCIMAS\nCooperative Institute for Mesoscale Meteorological Studies\nCIMMS\nCIRA\nCooperative Institute for Research in the Atmosphere\nCooperative Institute for Research in Environmental Sciences\nCIRES\nCOADS\nComprehensive Ocean-Atmosphere Data Set\nCoastal Ocean Dynamics Applications Radar\nCODAR\nCONvective Dispersion Observed by Remote Sensors\nCONDORS\nClimate Research Project (ERL/ESG)\nCRP\nCommonwealth Scientific and Industrial Research Organization\nCSIRO\n(Australia)\nCSU\nColorado State University\nCTD\nconductivity, temperature, depth\nCWP\nCentral Weather Processor\nCWSU\nCenter Weather Service Unit\nDIAL\ndifferential absorption lidar\nDLM\ndeep-layer mean\nDMS\ndimethyl sulfide\nDNA\nDefense Nuclear Agency\nDOC\ndissolved organic carbon\nDOD\nDepartment of Defense\nDOE\nDepartment of Energy\nDOPLIGHT\nDOPpler-LIGHTning\n249","DRASER\nDoppler Radar And Storm Electricity Research (NSSL)\nDSET\nDesert Sunshine Exposure Test\nECMWF\nEuropean Center for Medium-range Weather Forecasting\nELF\nextremely low frequency\nENAMAP\nEastern North American Model of Air Pollution\nENSO\nEl Nino/Southern Oscillation\nEOF\nempirical orthogonal function\nEPA\nEnvironmental Protection Agency\nEPOCS\nEquatorial Pacific Ocean Climate Studies\nERL\nEnvironmental Research Laboratories (NOAA)\nESG\nEnvironmental Sciences Group (ERL)\nFAA\nFederal Aviation Administration\nFACE\nFlorida Area Cumulus Experiment\nFDP\nfluorescent dye particles\nFGGE\nFirst GARP Global Experiment\nFM-CW\nfrequency modulation-continuous wave\nFOCI\nFisheries Oceanography Cooperative Investigations (NOAA)\nFOX\nFisheries Oceanography Experiment\nGARP\nGlobal Atmospheric Research Program\nGASP\nGlobal Air Sampling Program\nGCM\ngeneral circulation model\nGEP\ngood éngineering practice\nGFDL\nGeophysical Fluid Dynamics Laboratory (ERL)\nGLERL\nGreat Lakes Environmental Research Laboratory (ERL)\nGMCC\nGeophysical Monitoring for Climatic Change (ARL)\nGOES\nGeostationary Operational Environmental Satellite\nGRAMA\nGreen River Ambient Model Assessment\nGTS\nGlobal Telecommunication System\nHEPAD\nHigh Energy Proton and Alpha Detector\nHF\nhigh frequency\nHOT\nHydrometeorological Operational Tool\nHRC\nhighly reflective clouds\nICE\nInternational Cometary Explorer\nIMETS\nInteractive Meteorological Educational and Training System\n(PROFS)\nI/O\ninput/output\nIPC\nInternational Pyrheliometer Comparison\nIRIS\nInternational Research Investigations of the Subarctic\nISEE\nInternational Sun-Earth Explorer\nITCZ\nintertropical convergence zone\nJAWS\nJoint Airport Weather Studies\nJIC\nJoint Ice Center\nJIMAR\nJoint Institute for Marine and Atmospheric Research\nJISAO\nJoint Institute for Study of the Atmosphere and Ocean\nJSPO\nJoint System Program Office (NEXRAD)\nKSC\nKennedy Space Center\n250","limited fine mesh\nLFM\nLimb Infrared Monitor of the Stratosphere\nLIMS\nlaser magnetic resonance\nLMR\nMesoscale Applications Group (ESG/WRP)\nMAG\nMiddle Atmosphere Program (SEL)\nMAP\nMesoscale Analysis and Prediction System (PROFS)\nMAPS\nMesoscale Atmospheric Transport Studies\nMATS\nmesoscale convective complex\nMCC\nmesoscale convective system\nMCS\nMedium Energy Proton and Electron Detector\nMEPED\nMinimum Energy Routes using Interactive Techniques (NASA)\nMERIT\nMEtropolitan TRacer EXperiment\nMETREX\nmovable fine-mesh [hurricane model)\nMFM\nmagnetohydrodynamic\nMHD\nMarginal Ice Zone EXperiment\nMIZEX\nMesoscale Research Group (ESG/WRP)\nMRG\nmulti-spectral imagery\nMSI\nMesoscale Studies Group (ERL/ESG)\nMSG\nmesosphere-stratosphere-troposphere\nMST\nNational Acid Precipitation Assessment Program\nNAPAP\nNational Aeronautics and Space Administration\nNASA\nNational Center for Atmospheric Research\nNCAR\nNOAA Data Buoy Center\nNDBC\nNaval Environmental Prediction Research Facility\nNEPRF\nNorthEast Regional Oxidation Study\nNEROS\nNational Environmental Satellite, Data, and Information Service\nNESDIS\n(NOAA)\nNEXt-generation weather RADar\nNEXRAD\nNational Hurricane Center (NWS)\nNHC\nNational Interagency Coordinating Group\nNICG\nNational Meteorological Center (NWS)\nNMC\nNational Oceanic and Atmospheric Administration\nNOAA\nNavy Oceanographic Meteorological Automatic Device\nNOMAD\nNORth PAcific Experiment\nNORPAX\nNational Ocean Service (NOAA)\nNOS\nNOAA Operational VAS Assessment\nNOVA\nNational Science Foundation\nNSF\nNational Severe Storms Laboratory (ERL)\nNSSL\nnumerical weather prediction\nNWP\nNational Weather Service\nNWS\nOcean Assessment Division (NOS)\nOAD\nOffice of Aircraft Operations (NOAA)\nOAO\nOmega dropwindsonde\nODW\nOffice of Health and Environmental Research\nOHER\nOklahoma-Kansas PRE-STORM\nO-K PRE-STORM\nOak Ridge National Laboratory\nORNL\nOcean Service Center\nOSC\nPrecipitation Augmentation for Crops Experiment\nPACE\npolycyclic aromatic hydrocarbon\nPAH\nplanetary boundary layer\nPBL\n251","PBM\nPhotochemical Box Model\nPCA\npolar cap absorption\nPEM\nPollution Episodic Model\nPEPE\nProlonged Episode Pollution Experiment\nPEQUOD\nPacific EQUatorial Ocean Dynamics\nPIXE\nProton-Induced X-ray Emission\nPMEL\nPacific Marine Environmental Laboratory (ERL)\nPPI\nplan position indicator\nP-PRIME\nPollutant-Particle Relationships In the Marine Environment\nPRE-STORM\nPreliminary Regional Experiment for STORM-Central\nPROFS\nProgram for Regional Observing and Forecasting Services\n(ERL/ESG)\nPROVAS\nPROfiler-VAS\nQSTING\nquasi-spectral time integration on nested grids\nRADAP\nRAdar DAta Processor\nRADRES\nRADar REsolution Study (PROFS)\nRAMM\nRegional And Mesoscale Meteorology (NESDIS)\nRAPS\nRegional Air Pollution Study\nRITS\nRadiatively Important Trace Species\nROM\nRegional Oxidant Model\nRSMAS\nRosenstiel School of Marine and Atmospheric Science\n(U. of Miami)\nSAGA\nSoviet-American Gases and Aerosol\nSAGE\nStratospheric Aerosol and Gas Experiment\nSANBAR\nSANder's BARotropic [model]\nSAO\nsemiannual oscillation\nSAP\nspline analysis package\nSBC\nstationary band complex\nSBUV\nsolar backscatter ultraviolet\nSEADEX\nShoreline Environmental Atmospheric Diffusion Experiment\nSEFC\nSouthEast Fisheries Center (NMFS)\nSEL\nSpace Environment Laboratory (ERL)\nSELDADS\nSEL Data Acquisition and Display System\nSELSIS\nSEL Solar Imaging System\nSEM\nSpace Environment Monitor\nSESC\nSpace Environment Services Center (SEL)\nSFMR\nstepped-frequency microwave radiometer\nSIO\nScripps Institution of Oceanography\nSLAR\nside-looking airborne radar\nSLEUTH\nSystem for Locating Eruptive Underwater Turbidity and\nHydrography\nSLP\nsea level pressure\nSME\nSolar Mesosphere Explorer\nSPCZ\nSouth Pacific convergence zone\nSPM\nsuspended particulate matter\nSST\nsea surface temperature\nST\nstratosphere-troposphere\nSTACS\nSubTropical Atlantic Climate Studies\nSTATE\nSTructure and Atmosphere Turbulence Environment\nSTORM\nSTormscale Operational and Research Meteorology\n252","Trans-Atlantic Geotraverse\nTAG\nTransformation and Assimilation of Pollutants\nTAP\n[by Natural Processes]\nTsunami Hazard Reduction Using System Technology\nTHRUST\nTelevision and InfraRed Observation Satellite\nTIROS\nTropical Oceans and Global Atmosphere\nTOGA\n[Ocean] TOPography EXperiment\nTOPEX\nTotal Ocean Profiling System\nTOPS\nTOtable Tornado Observatory\nTOTO\nTIROS Operational Vertical Sounder\nTOVS\nThunderstorm Research International Program\nTRIP\nU.S. Air Force\nUSAF\nU.S. Geological Survey\nUSGS\nultraviolet\nUV\nvelocity-azimuth display\nVAD\nVISSR Atmospheric Sounder\nVAS\nVENTing EXperiment\nVENTEX\nvery high frequency\nVHF\nVisible Infrared Spin Scan Radiometer\nVISSR\nvery low frequency\nVLF\nvolume velocity processing\nVVP\nWestern ATlantic Ocean Experiment\nWATOX\nWorld Data Center-A\nWDC-A\nWIND-measuring SATellite\nWINDSAT\nWorld Meteorological Organization\nWMO\nWeather Modification Program (ERL/ESG)\nWMP\nWorld Ocean Circulation Experiment\nWOCE\nWave Propagation Laboratory (ERL)\nWPL\nWeather Research Program (ERL/ESG)\nWRP\nWorld Radiometer Reference\nWRR\nWeather Service Forecast Office\nWSFO\nWorld Warning Agency\nWWA\nwesterly wind/convection episode\nWWCE\nexpendable bathythermograph\nXBT\n*U.S. GOVERNMENT PRINTING OFFICE:1985-576-000/ 20008\n253"]}