NOAA Atlas NESDIS 43 WORLD OCEAN DATABASE 2001 Volume 2: Temporal Distribution of Bathythermograph Profiles Timothy P. Boyer Margarita E. Conkright John I. Antonov Olga K. Baranova Hernan E. Garcia Robert Gelfeld Daphne Johnson Ricardo A. Locarnini Paulette Murphy Todd D. O’Brien Igor Smolyar Cathy Stephens Editor: Sydney Levitus National Oceanographic Data Center Ocean Climate Laboratory Silver Spring, MD March 2002 U.S. DEPARTMENT OF COMMERCE Donald L. Evans, Secretary National Oceanic and Atmospheric Administration Vice Admiral Conrad C. Lautenbacher, Jr., USN (Ret.), Under Secretary National Environmental Satellite, Data, and Information Service Gregory W. Withee, Assistant Administrator National Oceanographic Data Center Additional copies of this publication, as well as information about NODC data holdings, and services, are available on request directly from NODC. NODC information and data are also available over the Internet through the NODC World Wide Web site. National Oceanographic Data Center User Services Team NOAA/NESDIS E/OC1 SSMC-III, 4th Floor 1315 East-West Highway Silver Spring, MD 20910-3282 Telephone: (301)713-3277 Fax: (301)713-3302 E-mail: services@nodc.noaa.gov NODC World Wide Web site: http://www.nodc.noaa.gov/ For updates on the data, documentation and additional information about WOD01 please refer to: http://www.nodc.noaa.gov click on: Ocean Climate Laboratory click on: Products This publication should be cited as: T. P. Boyer, M. E. Conkright, J. I. Antono v, O. Baranova, H. E. Garcia, R. Gelfeld, D. Johnson, R. A. Locarnini, P. P. Murphy, T. D. O'Brien, I. Smolyar, C. Stephens, 2002: World Ocean Database 2001, Volume 2: Temporal Distribution of Bathythermograph Profiles. S. Levitus, Ed., NOAA Atlas NESDIS 43, U.S. Government Printing Office, Wash., D.C., 119 pp., CD-ROMs. Contents Preface ................................................................. viii Acknowledgments .......................................................... ix Chapter 1 Temporal Distribution of Mechanical Bathythermograph Profiles ............. 1 Abstract ............................................................................. 1 1. Introduction .................................................................... 1 2. MBT accuracy .................................................................. 2 3. MBT profile distributions ............................................... 2 4. Bibliography ................................................................... 3 5. Appendix A: Distributions for individual years of all MBT profiles in WOD01 .......... 14 Chapter 2 Temporal Distribution of Expendable Bathythermograph Profiles ............ 71 1. Introduction .................................................................... 71 2. The XBT drop rate error .................................................. 71 3. XBT profile distributions ............................................... 71 4. Bibliography ................................................................... 81 5. Appendix B: Distributions for individual years of all XBT profiles in WOD01 .......... 83 LIST OF TABLES Table 1. Comparison of observations taken with mechanical bathythermographs and reversing thermometers reproduced from Leipper and Burt (1948). Table 2. National contributions of Mechanical Bathythermograph (MBT) profiles sorted by percent contribution of each country. Table 3. The number of MBT profiles in WOD01 as a function of year for the World Ocean. Table 4. The number of MBT profiles in WOD01 as a function of year for the southern hemisphere. Table 5. The number of MBT profiles in WOD01 as a function of year for the northern hemisphere. Table 6. National contributions of Expendable Bathymeterograph (XBT) profiles sorted by percent contribution of each country. Table 7. The number of XBT profiles in WOD01 as a function of year for the World Ocean. Table 8. The number of XBT profiles in WOD01 as a function of year for the southern hemisphere. Table 9. The number of XBT profiles in WOD01 as a function of year for the northern hemisphere. LIST OF FIGURES Fig. 1 Time series of MBT profiles in WOD01 for the world ocean as a function of year. Fig. 2 Time series of MBT profiles in WOD01 for the southern hemisphere as a function of year. Fig. 3 Time series of MBT profiles in WOD01 for the northern hemisphere as a function of year. Fig. 4 Distribution of all profiles in the MBT files of WOD01. Fig. 5 Time series of XBT profiles in WOD01 for the world ocean as a function of year. Fig. 6 Time series of XBT profiles in WOD01 for the southern hemisphere as a function of year. Fig. 7 Time series of XBT profiles in WOD01 for the northern hemisphere as a function of year. Fig. 8 Distribution of all profiles in the XBT files of WOD01. APPENDIX A Fig. A1 WOD01 MBT profile distribution for 1941. Fig. A2 WOD01 MBT profile distribution for 1942. Fig. A3 WOD01 MBT profile distribution for 1943. Fig. A4 WOD01 MBT profile distribution for 1944. Fig. A5 WOD01 MBT profile distribution for 1945. Fig. A6 WOD01 MBT profile distribution for 1946. Fig. A7 WOD01 MBT profile distribution for 1947. Fig. A8 WOD01 MBT profile distribution for 1948. Fig. A9 WOD01 MBT profile distribution for 1949. Fig. A10 WOD01 MBT profile distribution for 1950. Fig. A11 WOD01 MBT profile distribution for 1951. Fig. A12 WOD01 MBT profile distribution for 1952. Fig. A13 WOD01 MBT profile distribution for 1953. Fig. A14 WOD01 MBT profile distribution for 1954. Fig. A15 WOD01 MBT profile distribution for 1955. Fig. A16 WOD01 MBT profile distribution for 1956. Fig. A17 WOD01 MBT profile distribution for 1957. Fig. A18 WOD01 MBT profile distribution for 1958. Fig. A19 WOD01 MBT profile distribution for 1959. Fig. A20 WOD01 MBT profile distribution for 1960. Fig. A21 WOD01 MBT profile distribution for 1961. Fig. A22 WOD01 MBT profile distribution for 1962. Fig. A23 WOD01 MBT profile distribution for 1963. Fig. A24 WOD01 MBT profile distribution for 1964. Fig. A25 WOD01 MBT profile distribution for 1965. Fig. A26 WOD01 MBT profile distribution for 1966. Fig. A27 WOD01 MBT profile distribution for 1967. Fig. A28 WOD01 MBT profile distribution for 1968. Fig. A29 WOD01 MBT profile distribution for 1969. Fig. A30 WOD01 MBT profile distribution for 1970. Fig. A31 WOD01 MBT profile distribution for 1971. Fig. A32 WOD01 MBT profile distribution for 1972. Fig. A33 WOD01 MBT profile distribution for 1973. Fig. A34 WOD01 MBT profile distribution for 1974. Fig. A35 WOD01 MBT profile distribution for 1975. Fig. A36 WOD01 MBT profile distribution for 1976. Fig. A37 WOD01 MBT profile distribution for 1977. Fig. A38 WOD01 MBT profile distribution for 1978. Fig. A39 WOD01 MBT profile distribution for 1979. Fig. A40 WOD01 MBT profile distribution for 1980. Fig. A41 WOD01 MBT profile distribution for 1981. Fig. A42 WOD01 MBT profile distribution for 1982. Fig. A43 WOD01 MBT profile distribution for 1983. Fig. A44 WOD01 MBT profile distribution for 1984. Fig. A45 WOD01 MBT profile distribution for 1985. Fig. A46 WOD01 MBT profile distribution for 1986. Fig. A47 WOD01 MBT profile distribution for 1987. Fig. A48 WOD01 MBT profile distribution for 1988. Fig. A49 WOD01 MBT profile distribution for 1989. Fig. A50 WOD01 MBT profile distribution for 1990. Fig. A51 WOD01 MBT profile distribution for 1991. Fig. A52 WOD01 MBT profile distribution for 1992. Fig. A53 WOD01 MBT profile distribution for 1993. Fig. A54 WOD01 MBT profile distribution for 1994. Fig. A55 WOD01 MBT profile distribution for 1995. Fig. A56 WOD01 MBT profile distribution for 1996. Fig. A57 WOD01 MBT profile distribution for 1997. Fig. A58 WOD01 MBT profile distribution for 1998. Fig. A59 WOD01 MBT profile distribution for 1999. APPENDIX B Fig. B1 WOD01 XBT profile distribution for 1966. Fig. B2 WOD01 XBT profile distribution for 1967. Fig. B3 WOD01 XBT profile distribution for 1968. Fig. B4 WOD01 XBT profile distribution for 1969. Fig. B5 WOD01 XBT profile distribution for 1970. Fig. B6 WOD01 XBT profile distribution for 1971. Fig. B7 WOD01 XBT profile distribution for 1972. Fig. B8 WOD01 XBT profile distribution for 1973. Fig. B9 WOD01 XBT profile distribution for 1974. Fig. B10 WOD01 XBT profile distribution for 1975. Fig. B11 WOD01 XBT profile distribution for 1976. Fig. B12 WOD01 XBT profile distribution for 1977. Fig. B13 WOD01 XBT profile distribution for 1978. Fig. B14 WOD01 XBT profile distribution for 1979. Fig. B15 WOD01 XBT profile distribution for 1980. Fig. B16 WOD01 XBT profile distribution for 1981. Fig. B17 WOD01 XBT profile distribution for 1982. Fig. B18 WOD01 XBT profile distribution for 1983. Fig. B19 WOD01 XBT profile distribution for 1984. Fig. B20 WOD01 XBT profile distribution for 1985. Fig. B21 WOD01 XBT profile distribution for 1986. Fig. B22 WOD01 XBT profile distribution for 1987. Fig. B23 WOD01 XBT profile distribution for 1988. Fig. B24 WOD01 XBT profile distribution for 1989. Fig. B25 WOD01 XBT profile distribution for 1990. Fig. B26 WOD01 XBT profile distribution for 1991. Fig. B27 WOD01 XBT profile distribution for 1992. Fig. B28 WOD01 XBT profile distribution for 1993. Fig. B29 WOD01 XBT profile distribution for 1994. Fig. B30 WOD01 XBT profile distribution for 1995. Fig. B31 WOD01 XBT profile distribution for 1996. Fig. B32 WOD01 XBT profile distribution for 1997. Fig. B33 WOD01 XBT profile distribution for 1998. Fig. B34 WOD01 XBT profile distribution for 1999. Fig. B35 WOD01 XBT profile distribution for 2000. Fig. B36 WOD01 XBT profile distribution for 2001. PREFACE The oceanographic databases described by this atlas series greatly expands on the World Ocean Database 1998 (WOD98) product. We have expanded these earlier databases to include data from new instrument types such as profiling floats and new variables such as pCO₂ and TCO₂. Previous oceanographic databases including the NODC/WDC profile archives, and products derived from these databases, have proven to be of great utility to the international oceanographic, climate research, and operational environmental forecasting communities. In particular, the objectively analyzed fields of temperature and salinity derived from these databases have been used in a variety of ways. These include use as boundary and/or initial conditions in numerical ocean circulation models, for verification of numerical simulations of the ocean, as a form of "sea truth" for satellite measurements such as altimetric observations of sea surface height, and for planning oceanographic expeditions. Increasingly nutrient fields are being used to initialize and/or verify biogeochemical models of the world ocean. The databases, and products based on these databases, are critical for support of international assessment programs such as the Intergovernmental Program on Climate Change (IPCC) of the United Nations. It is well known that the amount of carbon dioxide in the earth's atmosphere will most likely double during the next century compared to CO₂ levels that occurred at the beginning of the Industrial Revolution. Regardless of one's scientific and/or political view of a possible "enhanced greenhouse warming" due to the increase of carbon dioxide, it is necessary that the international scientific community have access to the most complete historical oceanographic databases possible in order to study this problem, as well as other scientific and environmental problems. The production of oceanographic databases is a major undertaking. Such work benefits from the input of many individuals and organizations. We have tried to structure the data sets in such a way as to encourage feedback from experts around the world who have knowledge that can improve the data and metadata contents of the database. It is only with such feedback that high quality global ocean databases can be prepared. Just as with scientific theories and numerical models of the ocean and atmosphere, the development of global ocean databases is not carried out in one giant step, but proceeds in an incremental fashion. In the acknowledgment section of this publication we have expressed our view that creation of global ocean databases is only possible through the cooperation of scientists, data managers, and scientific administrators throughout the international community. I thank my colleagues at the Ocean Climate Laboratory of NODC for their dedication to the project leading to publication of this atlas series. Their commitment has made this database possible. It is my belief that the development and management of national and international oceanographic data archives is best performed by scientists who are actively working with the data. Sydney Levitus National Oceanographic Data Center/World Data Center for Oceanography- Silver Spring Silver Spring, MD March 2002 Acknowledgments This work was made possible by a grant from the NOAA Climate and Global Change Program which enabled the establishment of a research group, the Ocean Climate Laboratory (OCL), at the National Oceanographic Data Center. The purpose of the OCL is to prepare research quality oceanographic databases, as well as to compute objective analyses of, and diagnostic studies based on, these databases. The data made available as part of this atlas include a part of the oceanographic data archives maintained by NODC/WDC as well as data acquired as a result of the IODE/IOC “Global Oceanographic Data Archaeology and Rescue” (GODAR) project. At NODC/WDC, “data archaeology and rescue” projects are supported with funding from the NOAA Environmental Science Data and Information Management (ESDIM) Program and NOAA Climate and Global Change Program. The majority of funding for these efforts is now provided by the ESDIM program. Support for this work from joint NASA/NOAA and DOE/NOAA Global Change data management programs is appreciated. Support for some of the regional IOC/GODAR meetings was provided by the MAST program of the European Union. We acknowledge the scientists, technicians, and programmers who have submitted data to national and regional data centers as well as the managers and staff at the various data centers. Our database allows for the storage of metadata including information about Principal Investigators to recognize their efforts. The OCL expresses thanks to those who provided comments and helped develop an improved World Ocean Database 2001 (WOD01) product. In particular, Dr. Steve Worley of NCAR, and Steve Hankin of PMEL for testing the CD-ROMs prior to distribution. Roy Lowry (BODC) and Tom Whitworth (TAMU) for suggestions. Any errors in WOD01 are the responsibility of the Ocean Climate Laboratory. Ervin Godfrey Trammell and Charlotte Sazama of the NODC International Data Exchange Team helped locate data in the WDC archives for digitization. We thank Mike Chepurin, Igor Minin, Dan Smolyar, Alexandra Grodsky, and Carla Forgy of the OCL for their work in data digitization and their assistance in quality control of the data and metadata in WOD01. Renee Tatusko identified many missing metadata. The OCL acknowledges the help received over the last several years from colleagues in other NODC divisions. Francis Mitchell helped with all the code lists and accessions, Melanie Hamilton supplied GTSPP data. Declassification of naval oceanographic data by various navies is acknowledged. The Intergovernmental Oceanographic Commission has requested such declassification efforts in recent years. World Ocean Database 2001, Volume 2: Temporal Distribution of Bathythermograph Profiles T. P. Boyer, M. E. Conkright, J. I. Antonov, O. Baranova, H. Garcia, R. Gelfeld, D. Johnson, R. A. Locarnini, P. P. Murphy, T. D. O'Brien, I. Smolyar, C. Stephens Ocean Climate Laboratory National Oceanographic Data Center / NOAA Silver Spring, MD ABSTRACT This atlas describes a collection of scientifically quality controlled ocean Mechanical Bathythermograph (MBT) and Expendable Bathythermograph (XBT) profiles. Data distributions for individual years of all MBT and XBT profiles in the database are presented to provide information on the state of ocean MBT and XBT profile observations. Chapter 1: Temporal Distribution of Mechanical Bathythermograph Profiles 1. INTRODUCTION The Mechanical Bathythermograph (MBT) is an instrument developed during the late-1930's (Spilhaus, 1938) that can be dropped from either a stationary or moving ship to produce an upper ocean temperature profile. This instrument was a substantial improvement of an instrument known as the “oceanograph” which was designed by Dr. Carl Rossby and Dr. Karl Lange (Rossby and Montgomery, 1934) for the purpose of studying the upper ocean thermal structure. The introduction of the MBT into usage allowed ships to make synoptic surveys of oceanographic regions and for discovery of fine structure of the ocean’s thermal structure. Spilhaus (1941) used the instrument to identify “fine” structure (in the horizontal) from temperature profiles near the edge of the Gulf Stream. Pressure is determined from a pressure sensitive tube known as a Bourdon tube. A temperature sensitive element in the nose of the MBT enables the instrument to trace temperature as a function of depth. Different versions of the MBT have different maximum depth ranges with 295 m being the deepest depth measured from any U.S. version. Earlier versions of the instrument were limited to making measurements in the upper 140 m of the water column. A review of the development of the MBT is given by Spilhaus (1987). Another more comprehensive review is provided by Couper and LaFond (1970). The Digital Bathythermograph (DBT) instrument is a version of the MBT that reports data electronically rather than mechanically and may reach depths deeper than 295 m. DBT profiles are included in the MBT files. 2. MBT ACCURACY The accuracy of the MBT has been the subject of several studies. Leipper and Burt (1948) report the results of comparisons between MBT temperature measurements and near simultaneous reversing thermometer measurements which were made by D. Pritchard of the U.S. Navy Electronics Laboratory in Lake Meade. By comparing the temperature traces on the up and down casts of the MBT it was inferred that there was “an almost complete absence of internal waves of large amplitude and short period, hysteresis of the instruments, or rapid temperature changes due to advection”. These results are reproduced in Table 1 given below. Clearly there is good agreement between the reversing thermometer measurements (which typically had an accuracy of 0.02\(^\circ\)C at this period of time and the MBT measurements. However, there is a problem with interpreting the results from Table 1 because it is not clearly stated in the table or the text of the technical report of Leipper and Burt, what temperature units were used. Throughout their report, Leipper and Burt use the Fahrenheit scale. If this scale applies to the results in Table 1, then the agreement is impressive. If the results are in degrees centigrade, the agreement is less impressive but the data are still useful for many scientific purposes. Other studies attribute an accuracy of about 0.5 \(^\circ\)F to the MBT instrument (This figure is comparable to the accuracy of Expendable Bathymeterograph (XBT) probes for which the thermistor sensing element is not calibrated (Tabata, 1978)). Although both MBT and XBT probes are an order of magnitude less precise than reversing thermometers, the standard error of the mean of any estimate based on these temperature measurements decreases with the increase in number of data used. This applies to random errors. Hence, historical bathythermograph measurements provide valuable information when estimating mean features for by averaging over many measurements in space and/or time. In many countries and institutions the use of the MBT has been replaced by the XBT but in other countries and institutes MBT measurements continue to be made and transferred to oceanographic data centers. 3. MBT PROFILE DISTRIBUTIONS Figure 1 shows the number of MBT profiles contained in WOD01 for the World Ocean as a function of year. Figures 2 and 3 show the time series for the northern and southern hemispheres respectively. There are a total of 2,376,206 MBT profiles for the entire World Ocean with 264,648 profiles (11.1%) measured in the southern hemisphere and 2,111,558 profiles (88.9%) measured in the northern hemisphere. Table 1 provides the exact number of MBT profiles included in WOD01 as a function of year. Substantial numbers of MBT profiles were made by the U.S. Navy during World War II. All the WWII Pacific and Indian Ocean MBT profiles were digitized during the past several years as part of the NODC Data Archaeology and Rescue (NODAR) project with support from the NOAA CGC (Climate and Global Change) program and the NOAA ESDIM (Environmental Sciences and Information Management program). These data have been stored at the Scripps Institute of Oceanography. A more complete description of the data in this archive can be found in the report by Levitus et al. (1998). The geographic distribution of MBT profiles for individual years for 1941-1994 are shown in Figures A1-A54. Most profiles have been made in the northern hemisphere, but the southern hemisphere coverage has been increased due to international data archaeology and rescue efforts and the World Ocean Database project (Levitus et al. 1994, 2002). 4. BIBLIOGRAPHY Bralove, A.L., E.I Williams, Jr., 1952: A study of the errors of the bathythermograph, Final Report National Scientific Laboratories Inc., Contract No. NObsr 52348, 49 pp. Cascviano, D.L., 1967: Calibration Monitoring of Mechanical Bathythermographs, GMT, Dec./Jan. 1966/67, 19-21. Couper, B.K., and E.C. LaFond, 1970: Mechanical Bathythermograph: An Historical Review, in Advances in Instrumentation, Paper 735-70, Instrument Society of America, 25, Part 3, pp 735-70. Dinkel, C.R. and M. Stawnychy, 1973: Reliability Study of Mechanical Bathythermographs, Marine Technology Soc. Journ., 7(3),41-47. Hazelworth, J.B., 1966: Quantitative analysis of some bathythermograph errors, Tech. Rept ASWEPS No.11, U.S. Naval Oceanographic Office, pp. 27. IOC, 1975: Guide to oceanographic and marine meteorological instruments and observing practices. UNESCO, Paris,5 pp. and 12 chapters. Leipper, D.F. and R.M. Adams, 1952: Some methods used in representing bathythermograph data. The A. & M. College of Texas, Dept. of Oceanogr. Tech. Rept. 1, 6 pp., 9 figs. Leipper, D.F., R.M. Adams and Project staff , 1952: Summary of North Atlantic Weather Station Bathythermograph data 1946-1950, The A. & M. College of Texas, Dept of Oceanogr. Tech. Rept. 3, 2 pp., 40 figs. Leipper, D.F. and Project staff , 1954: Summary of North Pacific Weather Station Bathythermograph data 1943-1952, The A. & M. College of Texas, Dept of Oceanogr. Tech. Rept. 7, 2 pp., 64 figs. Leipper, D. F. and W.V. Burt, 1948: Annual Report, 1947-48 Bathythermograph Processing Unit. Scripps Institute of Oceanography, Oceanogr. Rep. No. 15, Scripps Institute ofOceanography, La Jolla, CA, 78 pp. Levitus, S., R. Gelfeld, T. Boyer, and D. Johnson, 1994: Results of the NODC and IOC Data Archaeology and Rescue projects. Key to Oceanographic Records Documentation No. 19, National Oceanographic Data Center, Washington, D.C., 67 pp. Levitus, S., M. Conkright Gregg, T.P. Boyer, R. Gelfeld, L. Stathoplos, D. Johnson, I. Smolyar, C. Stephens, G. Trammell, R. Moffatt, T. O'Brien, 1998: Results of the IOC Global Oceanographic Data Archaeology and Rescue (GODAR) project. NOAA NESDIS Technical Report. NODC, 1966: Atlas of bathythermograph data, Indian Ocean. U.S. Naval Oceanographic Office, NODC Publication G6, 129 pp. Robinson, M.K. and E.M. Drollinger, 1969: Bibliography of reports based on bathythermograph temperature data, SIO Reference Series 69-16, pp. 104. Rossby, C-G. and R. B. Montgomery, 1934: The layer of frictional influence in wind and ocean currents, in “Papers in Physical Oceanography and Meteorology of the Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, Vol. III, No. 3, pp. 73. Smed, J., 1978: Inventory of Oceanographic Investigations at North Atlantic Ocean Weather Stations 1947-1962. ICES, Charlottenlund, Denmark, 63 pp. Spilhaus, A.F., 1938: A bathythermograph. J. Mar. Res., 1, 95-100. Spilhaus, A. F., 1941: Fine structures on the edge of the Gulf Stream. Trans. Amer. Geophys. Union, 22, 478-484 Spilhaus, A.F., 1987: On Reaching 50: An Early History of the Bathythermograph, Sea Technology, 28,19-28. Stewart, R.L., 1963: Test and Evaluation of the Mechanical Bathythermograph, Unpublished manuscript, Marine Sciences Department, U.S. Naval Oceanographic Office, 33 pp. Tabata, S., 1978: Comparison of observations of sea surface temperatures at Ocean Weather Station P and NOAA Buoy Stations and those made by merchant ships traveling in their vicinities, in the Northeast Pacific Ocean. J. Appl. Meteor., 17, 374-385. U.S. Naval Oceanographic Office, 1968: Instruction Manual for Obtaining Oceanographic Data, Pub. 607, Sup. of Documents, Washington, D.C. U.S. Weather Bureau, 1956: Ocean Station Vessel Meteorological Records Survey: Atlantic and Pacific. U.S. Gov. printing Office, U.S. Gov. Printing Office, Washington, D.C., 106 pp. Vine, A.C., 1952: Oceanographic Instruments for Measuring Temperature, in Symposium on Oceanographic Instrumentation, Rancho Santa Fe, California. Table 1. Comparison of observations taken with Mechanical Bathythermographs and reversing thermometers reproduced from Leipper and Burt (1948).
TABLE I
OBSERVATIONS TAKEN WITH BATHYTHERMOGRAPHS AND REVERSING THERMOMETERS
BT No. of stations No. of thermometer observations Standard Deviation of Temperature Differences*
# 1784A (Shallow) 9 20 0.15
# 1258A (Deep) 10 41 0.19
# 514A (Deep) 12 36 0.10
*We reproduce this table as it appeared in the work by Leipper and Burt (1948). Unfortunately, they did not specify whether the units of temperature were reported in degrees centigrade or Fahrenheit. However, all other citations of temperature in their report were given in units of degrees Fahrenheit. Even if these results are in units of degrees centigrade, the agreement is still good. For example, individual XBT probes are accurate to a few tenths of a degree Centigrade. Table 2 National contributions of Mechanical Bathythermograph (MBT) profiles sorted by percent contribution of each country
NODC Country Name MBT Count % of Total
31UNITED STATES110090346.31
90RUSSIA43296618.21
49JAPAN33524714.10
18CANADA1959478.24
74UNITED KINGDOM1186444.99
32UNITED STATES466601.96
6GERMANY, FEDERAL REPUBLIC OF250051.05
33UNITED STATES231030.97
9AUSTRALIA184740.78
99UNKNOWN166360.70
35FRANCE135380.57
8ARGENTINA123030.52
64NETHERLANDS80880.34
48ITALY62680.26
65PERU52120.22
20CHILE41610.18
68PORTUGAL26280.11
61NEW ZEALAND24350.10
RCCONGO12340.05
11BELGIUM12180.05
58NORWAY9130.04
28ECUADOR8850.04
24KOREA, REPUBLIC OF8470.04
22COLOMBIA7470.03
93VENEZUELA6730.03
41INDIA5400.02
55MALAGASY REPUBLIC4050.02
36GREECE3270.01
SESENEGAL2450.01
29SPAIN1950.01
SLSIERRA LEONE1870.01
1CIVORY COAST1000.00
MOMONACO970.00
NINIGERIA890.00
14BRAZIL820.00
86THAILAND770.00
91SOUTH AFRICA200.00
GHGHANA120.00
The United States, Russia, and Japan have multiple country codes. This is because the NODC Institution Code is limited to two digits and these countries each have more than 99 institutions that can potentially transfer data to NODC/WDC. Table 3 The number of all MBT profiles in WOD01 as a function of year for the World Ocean. Total Number of Profiles = 2,376,206
YEAR PROFILE YEAR PROFILE YEAR PROFILE YEAR PROFILE
194110154195650666197140974198644478
19427014195760580197243558198740704
194317767195870159197334112198834877
194436902195965526197435133198921223
194541127196072367197527446199018703
19462382319617700919763356419918348
19472882619628555919773421419923832
19483036419639165219783575019933676
194936058196489173197939695199481
195050364196597277198031128199510
195150296196610698419812667119960
19526135119679432119822370419970
19535935219687546019832522419980
19545296619696079619843982919995
195545560197044918198435616
Table 4 The number of all MBT profiles in WOD01 as a function of year for the southern hemisphere. Total Number of Profiles = 264,648
YEAR PROFILE YEAR PROFILE YEAR PROFILE YEAR PROFILE
194110195643061971636219866007
19421384195784681972652219876409
194325681958107001973616919883654
19443389195991951974483919892661
19451007196099941975248719901353
194691419616945197651041991434
1947216919629447197769851992116
1948143196311417197859861993172
19495501964993519796857
195028719651038319805916
195146919661069519814665
1952276419671394019824172
195388619681081019834911
195410571969590119848200
195529781970595619846000
Table 5 The number of all MBT profiles in WOD01 as a function of year for the northern hemisphere. Total Number of Profiles = 2,111,558
YEAR PROFILE YEAR PROFILE YEAR PROFILE YEAR PROFILE
194110144195645760197134612198638471
19425630195752112197237036198734295
194315199195859459197327943198831223
194433513195956331197430294198918562
194540120196062373197524959199017350
19462290919617006419762846019917914
19472665719627611219772722919923716
19483019119638014519782976419933504
194935508196479238197932838199481
195050077196586894198025212199510
19514982719669628919812200619960
19525858719678038119821953219970
19535846619686465019832031319980
19545190919695489519843162919995
195542582197038962198429616
![Time series bar chart showing the number of MBT profiles in WOD01 for the world ocean as a function of year, with a peak around 1965 and a total of 2,376,206 profiles.](page_184_120_1680_1200.png) Fig. 1 Time series of MBT profiles in WOD01 for the world ocean as a function of year. Fig. 2 Time series of MBT profiles in WOD01 for the southern hemisphere as a function of year. ![Time series bar chart showing the number of MBT profiles in WOD01 for the southern hemisphere as a function of year, with a total of 264,648 profiles. The x-axis represents years from 41 to 01, and the y-axis represents the number of profiles from 0 to 110,000.](page_172_120_1696_1342.png) ![Time series bar chart showing the number of MBT profiles in WOD01 for the northern hemisphere as a function of year. The y-axis is labeled 'NUMBER OF PROFILES' (log scale), and the x-axis is labeled 'YEAR'. The total number of profiles is indicated as 2,111,558.](page_172_120_1696_1342.png) Fig. 3 Time series of MBT profiles in WOD01 for the northern hemisphere as a function of year. Fig. 4 Distribution of all profiles in the MBT files of WOD01. Dots show location of 1-degree squares containing any data. ![World map showing distribution of all profiles in the MBT files of WOD01. Dots represent locations of 1-degree squares containing any data.](page_128_120_1792_1342.png) 5. APPENDIX A: DISTRIBUTIONS FOR INDIVIDUAL YEARS OF ALL MBT PROFILES IN WOD01 This appendix contains yearly data distributions of all MBT profile data contained in WOD01. These maps provide some history of the observational progress of the field of oceanography. They also serve as indicators of whether or not a particular data set from a scientist or institution is part of the NODC/WDC archive. The exchange of information provided by the publication of such maps has provided us with valuable information about deficiencies in the database. The locations of all WOD01 MBT profiles are plotted including profiles that may be erroneously located over land. However, WOD01 contains some profiles from various lakes so care should be exercised in the use of these profiles and the determination as to whether they represent errors in locations. For all figures in Appendix A, a small dot indicates a one-degree square containing from one to four profiles and a large dot indicates five or more profiles. Fig. A1 WOD01 MBT profile distribution for year 1941 . Fig. A2 WOD01 MBT profile distribution for year 1942 . Fig. A3 WOD01 MBT profile distribution for year 1943 . Fig. A4 WOD01 MBT profile distribution for year 1944 . Fig. A5 WOD01 MBT profile distribution for year 1945 . Fig. A6 WOD01 MBT profile distribution for year 1946 . Fig. A7 WOD01 MBT profile distribution for year 1947 . Fig. A8 WOD01 MBT profile distribution for year 1948 . Fig. A9 WOD01 MBT profile distribution for year 1949 . Fig. A10 WOD01 MBT profile distribution for year 1950 . Fig. A11 WOD01 MBT profile distribution for year 1951 . Fig. A12 WOD01 MBT profile distribution for year 1952 . Fig. A13 WOD01 MBT profile distribution for year 1953 . Fig. A14 WOD01 MBT profile distribution for year 1954 . Fig. A15 WOD01 MBT profile distribution for year 1955 . Fig. A16 WOD01 MBT profile distribution for year 1956 . Fig. A17 WOD01 MBT profile distribution for year 1957 . Fig. A18 WOD01 MBT profile distribution for year 1958 . Fig. A19 WOD01 MBT profile distribution for year 1959 . Fig. A20 WOD01 MBT profile distribution for year 1960 . Fig. A21 WOD01 MBT profile distribution for year 1961 . Fig. A22 WOD01 MBT profile distribution for year 1962 . Fig. A23 WOD01 MBT profile distribution for year 1963 . Fig. A24 WOD01 MBT profile distribution for year 1964 . Fig. A25 WOD01 MBT profile distribution for year 1965 . Fig. A26 WOD01 MBT profile distribution for year 1966 . Fig. A27 WOD01 MBT profile distribution for year 1967 . Fig. A28 WOD01 MBT profile distribution for year 1968 . Fig. A29 WOD01 MBT profile distribution for year 1969 . Fig. A30 WOD01 MBT profile distribution for year 1970 . Fig. A31 WOD01 MBT profile distribution for year 1971 . Fig. A32 WOD01 MBT profile distribution for year 1972 . Fig. A33 WOD01 MBT profile distribution for year 1973 . Fig. A34 WOD01 MBT profile distribution for year 1974 . Fig. A35 WOD01 MBT profile distribution for year 1975 . Fig. A36 WOD01 MBT profile distribution for year 1976 . Fig. A37 WOD01 MBT profile distribution for year 1977 . Fig. A38 WOD01 MBT profile distribution for year 1978 . Fig. A39 WOD01 MBT profile distribution for year 1979 . Fig. A40 WOD01 MBT profile distribution for year 1980 . Fig. A41 WOD01 MBT profile distribution for year 1981 . Fig. A42 WOD01 MBT profile distribution for year 1982 . Fig. A43 WOD01 MBT profile distribution for year 1983 . Fig. A44 WOD01 MBT profile distribution for year 1984 . Fig. A45 WOD01 MBT profile distribution for year 1985 . Fig. A46 WOD01 MBT profile distribution for year 1986 . Fig. A47 WOD01 MBT profile distribution for year 1987 . Fig. A48 WOD01 MBT profile distribution for year 1988 . Fig. A49 WOD01 MBT profile distribution for year 1989 . Fig. A50 WOD01 MBT profile distribution for year 1990 . Fig. A51 WOD01 MBT profile distribution for year 1991 . Fig. A52 WOD01 MBT profile distribution for year 1992 . Fig. A53 WOD01 MBT profile distribution for year 1993 . Fig. A54 WOD01 MBT profile distribution for year 1994 . Fig. A55 WOD01 MBT profile distribution for year 1995 . Fig. A56 WOD01 MBT profile distribution for year 1999 . Chapter 2: Temporal Distribution of Expendable Bathythermograph Profiles 1. INTRODUCTION The Expendable Bathythermograph (XBT) was deployed beginning in 1966 and has replaced the MBT in many measurement programs. There are different models of XBT instruments which have different maximum depth penetration and/or other different characteristics. The T-4, T-6, and T-7 probes reach maximum depths of 450, 750, and 750 m respectively. The T-7 probe differs from the T-6 probe in that it can be dropped from a faster moving ship and still maintain certain accuracy standards. The T-5 probe reaches a maximum depth of about 1800 m. The depth of a temperature measurement from an XBT instrument is determined using the time elapsed between when the probe enters the water and the time each temperature measurement is made. A vendor supplied drop-rate equation is utilized. However, the vendor supplied drop-rate equation for T-4, T-6, and T-7 probes was found to have a systematic error and a new equation has been developed by the international research community (Hanawa et al., 1995; UNESCO, 1994). The recommended practice regarding exchange and archiving of XBT profiles is that XBT profile data be exchanged or sent to data centers without correction for the systematic depth error, until an “international mechanism is established to implement the general use of the new equation” (UNESCO, 1994). This policy is to avoid double corrections. 2. The XBT drop rate error The XBT instrument does not measure pressure or depth directly. Depth of the instrument is computed from the elapsed time from when the probe enters the water through use of a drop-rate equation. There are several models of the Sippican Expendable Bathythermograph instrument. The manufacturer’s drop rate equation for the T4, T-6, and T-7 models are known to contain a systematic error. To correct for this error a new drop rate equation has been computed (Hanawa et al., 1995; UNESCO, 1994). By international agreement (UNESCO, 1994), XBT profile depths are supposed to be reported and archived using depths computed from the “old” drop-rate equation. This policy is to avoid possible confusion as to whether the profiles have been converted or not so as to avoid double conversion. NODC/WDC archives the XBT data as submitted. The observed level XBT profiles are the same data as submitted by originators. However, in preparing standard level data for WOD98, the NODC/OCL corrected the depths of the originator’s XBT profiles using the new drop-rate equation before interpolating to standard levels. 3. XBT PROFILE DISTRIBUTIONS Figure 1 shows the number of XBT profiles contained in WOD01 for the World Ocean as a function of year. Figures 2 and 3 show the time series for the northern and southern hemispheres respectively. There are a total of 1,743,592 XBT profiles for the entire World Ocean with 312,290 profiles (17.9%) measured in the southern hemisphere and 1,431,300 profiles (82.1%) measured in the northern hemisphere. Table 1 provides the exact number of XBT profiles included in WOD01 as a function of year. The geographic distribution of XBT profiles for individual years for 1966-2001 are shown in Figures B1-B36. Most profiles have been made in the northern hemisphere, but the southern hemisphere coverage has been increased due to international data archaeology and rescue efforts and the World Ocean Database project (Levitus et al. 1994, 2002). Table 6 National contributions of (XBT) profiles sorted by percent contribution of each country.
NODC Country XBT % of
Country Name Count Total
31UNITED STATES54877931.47
32UNITED STATES24832814.24
49JAPAN23642413.56
74UNITED KINGDOM1649489.46
99UNKNOWN963215.52
9AUSTRALIA831554.77
6GERMANY, FEDERAL REPUBLIC OF565443.24
18CANADA486642.79
35FRANCE456902.62
54LIBERIA332901.91
PAPANAMA326971.88
64NETHERLANDS152940.88
90RUSSIA145780.84
S1SINGAPORE145650.84
BHBAHAMAS97130.56
33UNITED STATES88740.51
AGANTIGUA69750.40
58NORWAY69080.40
91SOUTH AFRICA58900.34
26DENMARK57240.33
SVSAINT VINCENT55980.32
61NEW ZEALAND55870.32
76CHINA, THE PEOPLES REPUBLIC OF45680.26
77SWEDEN45520.26
46ICELAND43480.25
HKHONG KONG32100.18
29SPAIN29950.17
BABARBADOS26010.15
20CHILE24380.14
TNTONGA23280.13
66PHILIPPINES22980.13
CYCYPRUS22580.13
57MEXICO22340.13
8ARGENTINA21840.13
KUKUWAIT18120.10
67POLAND13200.08
42INDONESIA12140.07
FJFJI ISLANDS8660.05
48ITALY7720.04
68PORTUGAL7320.04
65PERU7140.04
28ECUADOR4920.03
MLMALTA4310.02
41INDIA3620.02
14BRAZIL2180.01
SASAUDI ARABIA1970.01
ZZ MISCELLANEOUS ORGANIZATIONAL UNITS 195 0.01
95 YUGO SLAVIA 173 0.01
92 URUGUAY 146 0.01
MA MAURITIUS 77 0.00
7 GERMANY, DEMOCRATIC REPUBLIC OF 67 0.00
55 MALAGASY REPUBLIC 62 0.00
24 KOREA, REPUBLIC OF 53 0.00
IC IVORY COAST 43 0.00
UR UKRAINE 33 0.00
22 COLOMBIA 32 0.00
86 THAILAND 29 0.00
CR COSTA RICA 29 0.00
HO HONDURAS 12 0.00
SC SEYCHELLES 11 0.00
TT TRINIDAD/TOBAGO 6 0.00
21 TAIWAN 3 0.00
RU RUSSIA 1 0.00
The United States, Russia, and Japan have multiple country codes. This is because the NODC Institution Code is limited to two digits and these countries each have more than 99 institutions that can potentially transfer data to NODC/WDC. Table 7 The number of all XBT profiles in WOD01 as a function of year for the World Ocean. Total Number of Profiles = 1,743,592
YEAR PROFILE YEAR PROFILE YEAR PROFILE YEAR PROFILE
1966 1747 1975 54097 1984 54051 1993 61257
1967 9390 1976 48268 1985 67258 1994 52811
1968 26671 1977 54178 1986 72955 1995 62882
1969 34319 1978 52748 1987 69950 1996 48438
1970 44411 1979 52666 1988 59651 1997 41810
1971 57605 1980 52063 1989 42175 1998 34432
1972 53139 1981 50879 1990 76186 1998 36449
1973 54918 1982 53253 1991 63763 2000 23988
1974 54850 1983 53464 1992 57551 2001 9319
Table 8 The number of all XBT profiles in WOD01 as a function of year for the southern hemisphere. Total Number of Profiles = 312,290
YEAR PROFILE YEAR PROFILE YEAR PROFILE YEAR PROFILE
1966 168 1975 4304 1984 8718 1993 17135
1967 644 1976 5912 1985 10193 1994 17102
1968 2136 1977 4778 1986 11400 1995 17730
1969 2032 1978 5800 1987 13050 1996 14532
1970 2561 1979 7161 1988 9875 1997 15779
1971 5163 1980 6680 1989 8698 1998 12132
1972 6548 1981 5717 1990 14803 1998 9864
1973 6424 1982 9395 1991 14204 2000 7816
1974 5898 1983 10203 1992 14242 2001 3493
Table 9 The number of all XBT profiles in WOD01 as a function of year for the northern hemisphere. Total Number of Profiles = 1,431,300
YEAR PROFILE YEAR PROFILE YEAR PROFILE YEAR PROFILE
1966 1579 1975 49793 1984 45333 1993 44122
1967 8746 1976 42355 1985 57065 1994 35709
1968 24535 1977 49400 1986 61555 1995 45152
1969 32287 1978 46948 1987 56900 1996 33906
1970 41850 1979 45505 1988 49776 1997 26031
1971 52442 1980 45383 1989 33477 1998 22299
1972 46591 1981 45162 1990 61383 1998 26585
1973 48494 1982 43858 1991 49559 2000 16172
1974 48952 1983 43261 1992 43309 2001 5826
![Time series bar chart showing the number of XBT profiles in WOD01 for the world ocean as a function of year, from 1966 to 2000. The y-axis is labeled 'NUMBER OF PROFILES' and ranges from 0 to 90,000. The x-axis is labeled 'YEAR' and shows years from 66 to 00. The chart title states 'Total profiles = 1,743,592'.](page_180_120_1688_1202.png) Fig. 5 Time series of XBT profiles in WOD01 for the world ocean as a function of year. ![Time series bar chart showing the number of XBT profiles in WOD01 for the southern hemisphere as a function of year, with a total profile count of 312,290. The x-axis is labeled 'YEAR' (ranging from 66 to 00), and the y-axis is labeled 'NUMBER OF PROFILES' (ranging from 0 to 90,000).](page_184_120_1687_1202.png) Fig. 6 Time series of XBT profiles in WOD01 for the southern hemisphere as a function of year. ![Time series bar chart showing the number of XBT profiles in WOD01 for the northern hemisphere as a function of year, with a total of 1,431,300 profiles.](page_256_128_1536_1152.png) Fig. 7 Time series of XBT profiles in WOD01 for the northern hemisphere as a function of year. Fig. 8 Distribution of all profiles in the XBT files of WOD01. Dots show location of 1-degree squares containing any data. ![World map showing distribution of XBT profile locations](page_120_120_1768_1344.png) 4. BIBLIOGRAPHY Bailey, R. J., H. E. Phillips, and G. Meyers, 1989: Relevance to TOGA of systematic XBT errors, in Proceedings of the western Pacific International meeting and workshop on TOGA-COARE, eds. J. Picaut, R. Lukas, and T. Delcroix, 775-784. Bailey, R.J. and A. Gronell, undated: Scientific quality control at the WOCE Indian Ocean Thermal Data Assembly Centre (WOCE UOT/DAC). CSIRO Division of Oceanography, Hobart. Bailey, R.J., A. Gronell, 1994: Quality control cookbook for XBT data. CSIRO Marine Laboratories report No. 221, Hobart. Bane, J. and M. H. Sessions, 1984: A field performance test of the Sippican deep aircraft-deployed expendable bathythermograph. J. Geophys. Res., 89, 3615-3621. Boyd, J. and Linzell R., 1992: The temperature and depth accuracy of Sippican T-5 XBTs. J. Atmosph. and Oceanic Tech., 10, 128-136. Budeus,G. And G. Krause, 1993: On-cruise calibration of XBT probes. Deep-Sea Res., 40,1359-1363. Conkright M., S. Levitus, T. Boyer, 1994b: Quality control and processing of historical oceanographic and nutrient data. NOAA NESDIS Technical Report 79. Washington D.C. Demeo, R.P., 1969: The validity of expendable bathythermograph measurements. Trans. Of the marine Temperature Measurements Symposium. Marine technology Society, 155-179. Green, A.W., 1984: Bulk Dynamics of the expendable bathythermograph (XBT). Deep-Sea Res., 31, 415-426. Hallock, Z. R., and W. J. Teague, 1992: The fall rate of the T-7 XBT. J. Atmosph. and Oceanic Tech., 9, 470-483. Hanawa, K., and H. Yoritaka, 1987: Detection of systematic errors in XBT data and their correction. J. Oceanogr. Soc. Japan, 43, 68-76. Hanawa, K. and T. Yasuda, 1991: Re-examination of depth errors in XBT data and their correction. J. Atm. Ocean Tech., 8, 422-429. Hanawa, K., P. Rual, R. Bailey, A. Sy, and M. Szabados, 1995: A new depth-time equation for Sippican or TSK T-7, T-6 and T-4 expendable bathythermographs (XBT). Deep-Sea Res., 42, 1423-1452. Hayes, S.P., L.J. Mangum, J. Picaut, A. Sumi, K. Takeuchi, 1991: TOGA-TAO: a moored array for real-time measurements in the tropical Pacific Ocean. Bull. Amer. Meteorol. Soc., 339-347. Heinmiller, R.H., C.C. Ebbesmeyer, B.A. Taft, D.B. Olson, and O.P. Nikitin, 1983: Systematic errors in expendable bathythermographs (XBT) profiles. Deep-Sea Res., 30, 1185-1196. IOC, 1992a: Summary report of the IGOSS task team on quality control for automated systems and addendum to the summary report. IOC/INF-888, 1992. IOC, 1992b: Summary report of the IGOSS task team on quality control for automated systems and addendum to the summary report. IOC/INF-888-append., 1992. IOC, 1994: Calculation of new depth equations for expendable bathythermographs using a temperature-error-free method (application to Sippican/TSK T-7, T-6 and T-4 XBTs). IOC Tech. Series No. 42, 46 pp. Levitus, S., T. Boyer, 1994: World Ocean Atlas 1994, Vol. 5: Interannual variability of upper ocean thermal structure. NOAA Atlas NESDIS 5. U.S. Government Printing Office, Washington, D.C., 150 pp. Levitus, S., R. Gelfeld, T. Boyer, and D. Johnson, 1994: Results of the NODC and IOC Data Archaeology and Rescue projects. Key to Oceanographic Records Documentation No. 19, National Oceanographic Data Center, Washington, D.C., 67 pp. Levitus, S., M. Conkright, T.P. Boyer, R. Gelfeld, D. Johnson, I. Smolyar, C. Stephens, G. Trammell, R. Moffatt, T. O'Brien, L. Stathoplos, 1998: Results of the IOC Global Oceanographic Data Archaeology and Rescue (GODAR) project. NOAA NESDIS Technical Report. McPhaden, M., J., 1993: TOGA-TAO and the 1991-93 El Nino-Southern Oscillation Event. Oceanography, 6, 36-44. McDowell, S., A note on XBT accuracy. Polymode News, 29. Narayanan, S. and G.R. Lilly, 1993: On 5the accuracy of XBT profiles. Deep-Sea Res., 40, 2105-2113. Singer, J. J., 1990: On the error observed in electronically digitized T-7 XBT data. J. Atmos. Oceanic Technol., 7, 603-611. Sy, A., 1991:XBT measurements. WOCE reports, 67/91. UNESCO, 1994: Calculation of new depth equations for expendable bathythermographs using a temperature-error-free method (Application to Sippican/TSK T-7, T-6, and T-4 XBTs). Intergovernmental Oceanographic Commission technical series, Paris. Wright, D., and M. Szabados, 1989: Field evaluation of real-time XBT systems. Oceans 89 Proc., 5, 1621-1626. Wright, D., 1989: Field evaluation of the XBT bowing problem. NOS OOD Data Report 91-2, National Ocean Service, NOAA, Rockville, Maryland, U.S.A. 5. APPENDIX B: DISTRIBUTIONS FOR INDIVIDUAL YEARS OF ALL XBT PROFILES IN WOD01 This appendix contains yearly data distributions of all XBT profile data contained in WOD98. These maps provide some history of the observational progress of the field of oceanography. They also serve as indicators of whether or not a particular data set from a scientist or institution is part of the NODC/WDC archive. The exchange of information provided by the publication of such maps has provided us with valuable information about deficiencies in the database. The locations of all WOD01 XBT profiles are plotted including profiles that may be erroneously located over land. However, WOD01 contains some profiles from various lakes so care should be exercised in the use of these profiles and the determination as to whether they represent errors in locations. For all figures in Appendix A, a small dot indicates a one-degree square containing from one to four profiles and a large dot indicates five or more profiles. Fig. B1 WOD01 XBT profile distribution for year 1966 . Fig. B2 WOD01 XBT profile distribution for year 1967 . Fig. B3 WOD01 XBT profile distribution for year 1968 . ![World map showing XBT profile distribution for year 1969](page_0_0_2048_1536.png) Fig. B4 WOD01 XBT profile distribution for year 1969 . Fig. B5 WOD01 XBT profile distribution for year 1970 . Fig. B6 WOD01 XBT profile distribution for year 1971 . Fig. B7 WOD01 XBT profile distribution for year 1972 . Fig. B8 WOD01 XBT profile distribution for year 1973 . Fig. B9 WOD01 XBT profile distribution for year 1974 . Fig. B10 WOD01 XBT profile distribution for year 1975 . Fig. B11 WOD01 XBT profile distribution for year 1976 . Fig. B12 WOD01 XBT profile distribution for year 1977 . Fig. B13 WOD01 XBT profile distribution for year 1978 . Fig. B14 WOD01 XBT profile distribution for year 1979 . Fig. B15 WOD01 XBT profile distribution for year 1980 . Fig. B16 WOD01 XBT profile distribution for year 1981 . Fig. B17 WOD01 XBT profile distribution for year 1982 . Fig. B18 WOD01 XBT profile distribution for year 1983 . Fig. B19 WOD01 XBT profile distribution for year 1984 . Fig. B20 WOD01 XBT profile distribution for year 1985 . Fig. B21 WOD01 XBT profile distribution for year 1986 . Fig. B22 WOD01 XBT profile distribution for year 1987 . Fig. B23 WOD01 XBT profile distribution for year 1988 . Fig. B24 WOD01 XBT profile distribution for year 1989 . Fig. B25 WOD01 XBT profile distribution for year 1990 . Fig. B26 WOD01 XBT profile distribution for year 1991 . Fig. B27 WOD01 XBT profile distribution for year 1992 . Fig. B28 WOD01 XBT profile distribution for year 1993 . Fig. B29 WOD01 XBT profile distribution for year 1994 . Fig. B30 WOD01 XBT profile distribution for year 1995 . Fig. B31 WOD01 XBT profile distribution for year 1996 . Fig. B32 WOD01 XBT profile distribution for year 1997 . Fig. B33 WOD01 XBT profile distribution for year 1998 . Fig. B34 WOD01 XBT profile distribution for year 1999 . Fig. B35 WOD01 XBT profile distribution for year 2000 . Fig. B36 WOD01 XBT profile distribution for year 2001 .