Abstract The three-dimensional structure of the offshore export of Mississippi River (MR) waters is documented for the first time with in situ data. Numerical simulations and satellite data in the Gulf of Mexico (GoM) are also employed to study two pathways that were detected in summer of 2015, along the eastern and western sides of the Loop Current (LC). The initial formation of offshore branches was primarily due to the interaction of the anticyclonic LC and LC Eddy (which were close to the MR Delta and the Louisiana-Texas shelf-slope, respectively) with riverine waters that had been advected eastward by westerly winds (which reduced the westward buoyancy-driven currents). The interaction of anticyclonic circulation patterns with cyclones (LC Frontal Eddies) was found to influence the dynamics and structure of the branches. Thickness variability and other vertical characteristics of the brackish plumes were investigated from their origin in the northern GoM through their extension in the Straits of Florida. In particular, offshore branch thickness increased near the LC and LC Frontal Eddy fronts. The two types of pathways revealed different factors contributing to the low-salinity waters. Besides the MR input, precipitation contributed to the eastern pathway, while waters from additional northern GoM rivers contributed to the western pathway. The study offers new insights on the processes that control the formation and the offshore (southward) advection of low-salinity waters. These processes have implications on the properties of waters hundreds of kilometers from the northern river sources, extending to the southern Gulf and the Straits of Florida.
Lerner, B. M.; Gilman, J. B.; Aikin, K. C.; Atlas, E. L.; Goldan, P. D.; Graus, M.; Hendershot, R.; Isaacman-VanWertz, G. A.; Koss, A.; Kuster, W. C.; Lueb, R. A.; McLaughlin, R. J.; Peischl, J.; Sueper, D.; Ryerson, T. B.; Tokarek, T. W.; Warneke, C.; Yuan, B.; de Gouw, J. A.;
Volatile organic compounds were quantified during two aircraft-based field campaigns using highly automated, whole air samplers with expedited post-flight analysis via a new custom-built, field-deployable gas chromatography-mass spectrometry instrume...
Tevlin, A. G.; Li, Y.; Collett, J. L.; McDuffie, E. E.; Fischer, E. V.; Murphy, J. G.;
Published Date:
2017
Source:
Journal of Geophysical Research-Atmospheres, 122(22), 12468-12487.
Description:
Ammonia (NH3) mixing ratios were measured between the surface and 280m aboveground level from a moveable carriage at the Boulder Atmospheric Observatory tower in summer 2014 as part of the Front Range Air Pollution and Photochemistry Experiment. The ...
Colette, A.; Andersson, C.; Manders, A.; Mar, K.; Mircea, M.; Pay, M. T.; Raffort, V.; Tsyro, S.; Cuvelier, C.; Adani, M.; Bessagnet, B.; Bergstrom, R.; Briganti, G.; Butler, T.; Cappelletti, A.; Couvidat, F.; D'Isidoro, M.; Doumbia, T.; Fagerli, H.; Granier, C.; Heyes, C.; Klimont, Z.; Ojha, N.; Otero, N.; Schaap, M.; Sindelarova, K.; Stegehuis, A. I.; Roustan, Y.; Vautard, R.; van Meijgaard, E.; Vivanco, M. G.; Wind, P.;
Published Date:
2017
Source:
Geoscientific Model Development, 10(9), 3255-3276.
Description:
The EURODELTA-Trends multi-model chemistry-transport experiment has been designed to facilitate a better understanding of the evolution of air pollution and its drivers for the period 1990-2010 in Europe. The main objective of the experiment is to as...
We describe the University of Colorado mobile Solar Occultation Flux instrument (CU mobile SOF). The instrument consists of a digital mobile solar tracker that is coupled to a Fourier transform spectrometer (FTS) of 0.5 cm (-1) resolution and a UV-vi...
Giordano, M. R.; Kalnajs, L. E.; Avery, A.; Goetz, J. D.; Davis, S. M.; DeCarlo, P. F.;
Published Date:
2017
Source:
Atmospheric Chemistry and Physics, 17(1), 1-20.
Description:
Understanding the sources and evolution of aerosols is crucial for constraining the impacts that aerosols have on a global scale. An unanswered question in atmospheric science is the source and evolution of the Antarctic aerosol population. Previous ...
Sayers, M. J.; Grimm, A. G.; Shuchman, R. A.; Bosse, K. R.; Fahnenstiel, G. L.; Ruberg, S. A.; Leshkevich, G. A.;
Published Date:
2019
Source:
Journal of Great Lakes Research, 45(3), 508-521.
Description:
Blooms of harmful cyanobacteria (cyanoHABs) have occurred on an annual basis in western Lake Erie for more than a decade. Previously, we developed and validated an algorithm to map the extent of the submerged and surface scum components of cyanoHABs ...
Hill, M. C.; Bendlin, A. R.; Van Cise, A. M.; Milette-Winfree, A.; Ligon, A. D.; Ü, A. C.; Deakos, M. H.; Oleson, E. M.;
Published Date:
2019
Source:
Marine Mammal Science, 35(3), 797-824.
Description:
Abstract Little is known about short-finned pilot whales (Globicephala macrorhynchus) in the western North Pacific outside of Japanese coastal waters. To expand understanding of short-finned pilot whale ecology in the region, we conducted small-boat ...
Journal of Advances in Modeling Earth Systems, 9(1), 627-646.
Description:
Low and high clouds of shallow extent, especially stratocumulus and even more so for high-level cirrus clouds that reside where vertical resolution is particularly coarse, are poorly represented in large-scale models such as global climate models and...
Butler, A. H.; Sjoberg, J. P.; Seidel, D. J.; Rosenlof, K. H.;
Published Date:
2017
Source:
Earth System Science Data, 9(1), 63-76.
Description:
Major, sudden midwinter stratospheric warmings (SSWs) are large and rapid temperature increases in the winter polar stratosphere are associated with a complete reversal of the climatological westerly winds (i.e., the polar vortex). These extreme even...
Sayers, M. J.; Bosse, K. R.; Shuchman, R. A.; Ruberg, S. A.; Fahnenstiel, G. L.; Leshkevich, G. A.; Stuart, D. G.; Johengen, T. H.; Burtner, A. M.; Palladino, D.;
Published Date:
2019
Source:
Journal of Great Lakes Research, 45(3), 490-507.
Description:
Lake Erie has experienced dramatic changes in water quality over the past several decades requiring extensive monitoring to assess effectiveness of adaptive management strategies. Remote sensing offers a unique potential to provide synoptic monitorin...
Jensen, E. J.; Karcher, B.; Ueyama, R.; Pfister, L.; Bui, T. V.; Diskin, G. S.; DiGangi, J. P.; Woods, S.; Lawson, R. P.; Froyd, K. D.; Murphy, D. M.;
Published Date:
2018
Source:
Journal of Geophysical Research-Atmospheres, 123(21), 12210-12227.
Description:
Recent laboratory experiments have advanced our understanding of heterogeneous ice nucleation at low temperatures. We use these laboratory results, along with field measurements of aerosol composition, to constrain a parameterization of heterogeneous...
Stauffer, R. M.; Thompson, A. M.; Oltmans, S. J.; Johnson, B. J.;
Published Date:
2017
Source:
Journal of Geophysical Research-Atmospheres, 122(2), 1261-1280.
Description:
Much attention has been focused on the transport of ozone (O-3) to the western U.S., particularly given the latest revision of the National Ambient Air Quality Standard to 70 parts per billion by volume (ppbv) of O-3. This makes quantifying the contr...
Jathar, S. H.; Heppding, C.; Link, M. F.; Farmer, D. K.; Akherati, A.; Kleeman, M. J.; de Gouw, J. A.; Veres, P. R.; Roberts, J. M.;
Published Date:
2017
Source:
Atmospheric Chemistry and Physics, 17(14), 8959-8970.
Description:
Isocyanic acid (HNCO), an acidic gas found in tobacco smoke, urban environments, and biomass-burning-affected regions, has been linked to adverse health outcomes. Gasoline-and diesel-powered engines and biomass burning are known to emit HNCO and hypo...
Barkley, H. C.; Cohen, A. L.; Mollica, N. R.; Brainard, R. E.; Rivera, H. E.; DeCarlo, T. M.; Lohmann, G. P.; Drenkard, E. J.; Alpert, A. E.; Young, C. W.; Vargas-Ángel, B.; Lino, K. C.; Oliver, T. A.; Pietro, K. R.; Luu, V. H.;
Published Date:
2018
Source:
Communications Biology, 1(1), 177.
Description:
The oceans are warming and coral reefs are bleaching with increased frequency and severity, fueling concerns for their survival through this century. Yet in the central equatorial Pacific, some of the world’s most productive reefs regularly experie...
Yuan, B.; Coggon, M. M.; Koss, A. R.; Warneke, C.; Eilerman, S.; Peischl, J.; Aikin, K. C.; Ryerson, T. B.; de Gouw, J. A.;
Published Date:
2017
Source:
Atmospheric Chemistry and Physics, 17(8), 4945-4956.
Description:
Concentrated animal feeding operations (CAFOs) emit a large number of volatile organic compounds (VOCs) to the atmosphere. In this study, we conducted mobile laboratory measurements of VOCs, methane (CH4) and ammonia (NH3) downwind of dairy cattle, b...
Observations of atmospheric trace gases in the tropical upper troposphere (UT), tropical tropopause layer (TTL), and lower stratosphere (LS) require dedicated measurement platforms and instrumentation. Here we present a new limb-scanning Differential...
Palm, B. B.; Campuzano-Jost, P.; Day, D. A.; Ortega, A. M.; Fry, J. L.; Brown, S. S.; Zarzana, K. J.; Dube, W.; Wagner, N. L.; Draper, D. C.; Kaser, L.; Jud, W.; Karl, T.; Hansel, A.; Gutierrez-Montes, C.; Jimenez, J. L.;
Published Date:
2017
Source:
Atmospheric Chemistry and Physics, 17(8), 5331-5354.
Description:
Ambient pine forest air was oxidized by OH, O-3, or NO3 radicals using an oxidation flow reactor (OFR) during the BEACHON-RoMBAS (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics and Nitrogen - Rocky Mountain Biogenic Aero...
Long, C. S.; Fujiwara, M.; Davis, S.; Mitchell, D. M.; Wright, C. J.;
Published Date:
2017
Source:
Atmospheric Chemistry and Physics, 17(23), 14593-14629.
Description:
Two of the most basic parameters generated from a reanalysis are temperature and winds. Temperatures in the reanalyses are derived from conventional (surface and balloon), aircraft, and satellite observations. Winds are observed by conventional syste...
Perring, A. E.; Schwarz, J. P.; Markovic, M. Z.; Fahey, D. W.; Jimenez, J. L.; Campuzano-Jost, P.; Palm, B. D.; Wisthaler, A.; Mikoviny, T.; Diskin, G.; Sachse, G.; Ziemba, L.; Anderson, B.; Shingler, T.; Crosbie, E.; Sorooshian, A.; Yokelson, R.; Gao, R. S.;
Published Date:
2017
Source:
Journal of Geophysical Research-Atmospheres, 122(2), 1086-1097.
Description:
Water uptake by black carbon (BC)-containing aerosol was quantified in North American wildfire plumes of varying age (1 to similar to 40 h old) sampled during the SEAC(4)RS mission (2013). A Humidified Dual SP2 (HD-SP2) is used to optically size BC-c...