WOCE Section: P15S ExpoCode: 3175CG90_1-2 NOAA Data Report ERL PMEL-44 CTD MEASUREMENTS COLLECTED ON A CLIMATE AND GLOBAL CHANGE CRUISE ALONG 170°W DURING FEBRUARY-APRIL 1990 K. McTaggart (1) Pacific Marine Environmental Laboratory D. Wilson (2) Atlantic Oceanographic and Meteorological Laboratory Miami, Florida L. Mangum (1) Pacific Marine Environmental Laboratory Pacific Marine Environmental Laboratory Seattle, Washington June 1993 UNITED STATES NATIONAL OCEANIC Environmental DEPARTMENT OF AND ATMOSPHERIC Research COMMERCE ADMINISTRATION Laboratories _______________ _______________ ______________ Ronald H. Brown D. James Baker Alan R.Thomas Secretary Under Secretary Director for Oceans and Atmosphere/Administrator NOTICE Mention of a commercial company or product does not constitute an endorsement by NOAA/ERL. Use of information from this publication concerning proprietary products or the tests of such products for publicity or advertising purposes is not authorized. Contribution No. 1452 from NOAA/Pacific Marine Environmental Laboratory For sale by the National Technical Information Service, 5285 Port Royal Road - Springfield, VA 22161 _____________ 1 NOAA, Pacific Marine Environmental Laboratory, 7600 Sand Point Way N.E., Seattle, Washington 98115-0070 2 NOAA, Atlantic Oceanographic and Meteorological Laboratory, 4301 Rickenbacker Causeway, Miami, FL 33149 ABSTRACT. Summaries of Nell Brown Instrument System CTD measurements and hydrographic data acquired on a Climate and Global Change (CGC) cruise during the spring of 1990 aboard the NOAA ship Malcohn Baldhge are presented. The majority of these data were collected along 170°W from 5°N to 60°S. Additional data collected along a trackline from 60°S, 170°W to 46.3°S, 179.5°E, and along 32.5°S from 179°W to 170°W are also presented. Data acquisition and processing systems are described and calibration techniques are discussed. Station location, meteorological conditions, abbreviated CTD data listings, profiles, and potential temperature- salinity diagrams are shown for each cast. Section plots of oceanographic variables and hydrographic data listings are also given. 1. INTRODUCTION In support of NOAA's Climate Program, PMEL scientists have been measuring the growing burden of greenhouse gases in the thermocline waters of the Pacific Ocean and the overlying atmosphere since 1980. During leg I of this cruise, hydrographic and chemical measurements were made in a detailed section along 170°W in the southwestern Pacific Ocean. Goals included the assessment of the change in inventory of CFC- 11, CFC- 12, and anthropogenic CO2 since the first observations in the southwestern Pacific during 1984; observation of freons and other tracers in several crossings of the Deep Western Boundary Current; and observation of tracers in the bottom waters of the deep basin of the southwestern Pacific. During leg 2 of this cruise, measurements were made in the deep passages between the North and South Pacific Basins, across the Deep Western Boundary Current at 32.5°S, and across the equator. Figures I and 2 show the cruise track and station locations. In Figure 2, leg I stations are indicated by a circle and leg 2 stations are marked by a triangle. Table I provides a summary of cast information. 2. STANDARDS AND PRE-CRUISE CALIBRATIONS The Neil Brown Mark IIIb CTD profiler is designed to make precise, high resolution measurements of conductivity, temperature, and pressure in the ocean environment. Electrical conductivity of sea water is obtained using a miniature four-electrode ceramic cell and highly precise and stable interface electronics; temperature is determined using a platinum resistance thermometer. Pressure is determined using a high performance strain gage pressure transducer. A thermistor within the pressure sensor housing corrects pressure values for the effects of temperature changes on the sensor itself. Data from the underwater unit is transmitted in real time to a shipboard data terminal through a 3-conductor electro-mechanical cable. The data is in TELETYPE (TTY) format and uses a frequency shift key (FSK) modulated signal superimposed on the DC power supplied to the underwater unit. The EG&G conductivity sensor has a range of I to 65 mmho, an accuracy of ±0.005 mmho, resolution of 0.001 mmho, and stability of 0.003 mmho/month. The Rosemount platinum thermometer has a range of -32 to 32°C, an accuracy of ±0.005°C (-3 to 32°C), resolution of 0.0005°C, and stability of 0.001°C/month. The Paine pressure sensor has a range of 0 to 6500 db, an accuracy of ±6.5 db, resolution of 0.1 db, and stability of 0.1%/month. Pre-cruise calibrations were done at Northwest Regional Calibration Center (NRCC) in Bellevue, Washington. The CTD was placed in a temperature controlled bath and compared against a calibration standard at nine different temperatures ranging from 0 to 30°C. A linear fit was calculated for the platinum thermometer. A calibrated piston gauge was used to determine separate third- order fits for the pressure sensor at four temperatures for increasing pressure (a range of seven pressure values from 0 to 6300 db) and decreasing pressure (a range of six values from 6300 to 0 db). Temperature and pressure calibrations were crudely checked at sea by comparing values with those from deep reversing thermometers, but the stability of the temperature and pressure sensors is such that the sensors are more accurate than the reversing thermometers. The conductivity sensor, on the other hand, is not as stable relative to water sample values and is more accurately calibrated using water sample salinities. Immediately prior to tripping the rosette, values of pressure, temperature, and conductivity were recorded from the CTD deck unit. These upcast CTD values were used for comparison with the water sample values. 3. DATA ACQUISITION The CTD was deployed off the starboard platform of the Malcolm Baldrige using an Interocean winch throughout both legs of the cruise. A total of 64 CTD profiles were collected at 36 stations on leg I along 170°W from 15°S to 60°S, and along a trackline from 60°S, 170°W to 46.3°S, 179.5°E, including 21 deep casts to within 50 db of the bottom and 6 test/freon calibration casts. Cast 63 and 64 were freon calibration casts. CTD data from cast 63 is included in the data set although no bottle salts were drawn, but CTD data from cast 64 was not processed. A total of 46 CTD profiles were collected during leg 2 along 32.5°S from 178.8°W to 171.5°W, and along 170°W from 30°S to 5°N, including 13 deep casts to within 50 db of the bottom. PMEL's Nell Brown CTD/02 S/N 2044 (sampling rate 31 Hz) and a General Oceanics 24-bottle rosette were used for casts 0-10. Eight-hundred pounds of lead weight were attached to the frame to reduce the effects of surging. AOML's Neil Brown CTD S/N 2043 (sampling rate 31 Hz) and a General Oceanics 12-bottle rosette with 400 pounds of lead weight were used for casts 11-64 of leg I and throughout leg 2. Casts to within 50 meters of the bottom were made using a Benthos acoustic pinger mounted low and opposite the CTD sensor arm on the frame. The position of the package relative to the bottom was monitored on the ship's Precision Depth Recorder. Ten-liter Niskin bottles were used to collect water samples for salinity, oxygen, nutrients, CFC, helium, total CO, alkalinity, and dissolved inorganic carbon. Reversing thermometers were mounted on several Niskin bottles on each cast and were used to verify rosette trip sequence and monitor the CTD temperature sensor for calibration shifts. The package entered the water and was lowered at a rate of 30 m/min for the first 50 meters. To reduce the chance of contamination in the bottles, the package was not stopped just beneath the surface on its descent. Speed was increased at 50 meters to 45 m/min, and increased again at 200 meters to 60 m/min. Ship roll sometimes caused substantial variation about these mean lowering rates. A Neil Brown Mark III deck unit received the FSK signal from the CTD and displayed pressure, temperature, and conductivity values. An analog signal was forwarded from the deck unit to an XYY' recorder which monitored the data acquisition in real-time for signal spiking and problems with the electrical termination. An audio signal was forwarded to a video cassette recorder as a backup. The digitized data were forwarded to a microVAX and written directly to a disk file. Digitized data were also recorded on 9-track magnetic tape as an additional backup. The acquisition microVAX was equipped with Scientific Computer System (SCS) data acquisition software modified from PMEL/AOML source code. The disk files were transferred to a processing microVAX where PMEL's standard processing and plotting software were installed. Plots were generated after each cast to check for problems and monitor sensor drift. Backups of the raw and processed data were made on TK50 cartridge tapes and returned to PMEL. 3.1 Data Acquisition Problems Early into leg 1, patches of deteriorated cable were identified from near- surface to greater than 5000 meters. Efforts were made to reinforce damaged areas in order to continue with CTD operations. The oxygen sensor on CTD SiN 2044 started losing sensitivity before the cap was inadvertently left on during a deep cast which ruptured the sensor's membrane. Before the sensor could be replaced, the entire underwater package was lost during cast 10 when the cable parted with approximately 600 meters of cable out. An additional 4100 meters of cable was discarded and operations continued with the 12-bottle package. Multiple casts were made at selected stations to adequately sample the water column. CTD oxygen data were not processed. Problems existed throughout the cruise with the rosettes and the rosette deck units of both packages. Several deck units were tried. A strip chart recorder connected to the rosette deck units to monitor the signal voltages was helpful in determining misfires. Bottle salinity, oxygen and nutrient data were also used in an effort to determine the actual depth of each bottle fired. No bottles closed during cast 63 owing to a nicked connector. 3.2 Salinity Analyses Bottle salinity analyses were performed by survey personnel in a climate- controlled van using two Guildline Autosal Model 8400A inductive salinometers and IAPSO Standard Seawater from Wormley batch P 112. The commonly accepted precision of the Autosal is 0.001 psu, with an accuracy of 0.003 psu. The Autosals were standardized before each run and either at the end of each run or after no more than 48 samples. The drift during each run was monitored and individual samples were corrected for the drift during each run by linear interpolation. Bottle salinities were compared with computed CTD salinities to identify leaking bottles, as well as to monitor the conductivity sensor performance and drift. Problems developed with both autosals midway through the cruise but were fixed by ship's personnel. Generally, there was good agreement between preliminary CTD data and bottle salinities, with a standard error near .005 psu. Calibrated CTD salinities replace problem bottle salinities in the hydrographic data listing and are indicated by an asterisk. 4. POST-CRUISE CALIBRATIONS Pressure and temperature values for both CTDs were corrected using pre-cruise calibration coefficients. Reversing thermometer data showed no shifts in temperature and pressure calibrations within the resolution of these measurements. The new International Temperature Scale of 1990 (ITS-90) was not applied to the temperature values of this data set. Final calibrations for conductivity were determined by reading uncalibrated CTD upcast and sample salinity data and calculating a least squares linear fit between CTD and water sample conductivity, weighting all data equally. When the difference between CTD and water sample conductivity exceeded 2.8 times the standard deviation of the calculated fit, the calibration pair was thrown out. Another fit was then calculated with these points omitted and the process repeated until no calibration pairs are discarded. This cruise was separated into three groups: MAXIMUM STANDARD BIAS SLOPE RESIDUAL DEVIATION ____________________________________________________________________________ Casts 0-10: -2.0077199E-02 0.9993219 -0.019 0.0068 mmho/cm Casts 11-63: -0.7075790E-02 0.9987081 -0.010 0.0038 mmho/cm Casts 65-110: -1.4587455E-02 0.9986109 -0.010 0.0039 mmho/cm Casts 0-10: 16 values were discarded from a total of 122 in 6 repetitions. Casts 11-63: 36 values were discarded from a total of 555 in 8 repetitions. Casts 65-110: 49 values were discarded from a total of 510 in 7 repetitions. Deep potential temperature- salinity diagrams for each cast were used to check the quality of the fits. Where leg I stations were revisited on leg 2 (32.5°S, 30°S, 25°S, 20°S, and 15°S), overplots were generated. At reoccupied stations on leg 2, deep potential temperature- s ali ni ty diagrams of CTD and bottle data showed good correlation, however there was a difference of approximately 0.002 psu at two of the five reoccupied stations, 25°S and 30°S. Historical data from 1967 Scorpio, 1987 TEW, and 1974 GEOSECS cruises were examined and there also existed differences between these cruises in salinity of the deepest water masses of about 0.002 psu. Comparing the 1990 data set with these historical data, leg I salinity data was within this 0.002 psu difference. Therefore leg 2 data at stations 25°S and 30°S along 170°W (casts 77-84) were corrected. This was done by regridding leg I and leg 2 data at these two stations according to potential temperature. The range of potential temperature was around 0.6 to 0.8°C, with a grid size of 0.01°C. The mean difference in salinity between leg I and leg 2 casts was computed. For the station at 25°S, this value was 0.0018 psu; for the station at 30°S, it was 0.0021 psu. For each regridded scan of leg 2 data, a new conductivity was calculated using the value of salinity plus delta-salinity. The differences between the old and new conductivities were averaged (25°S = 0.0014 mmho/cm, 30°S = 0.0018 mmho/cm) and added to the conductivity calibration bias applied. Corrections were linearly interpolated over casts 77-84. 5. PROCESSING Raw CTD data files were restored from TK50 cartridge tapes and processed on PMEL microVAX node NBVAX. In order to eliminate anomalous excursions in the raw temperature and conductivity data associated with reversals in the direction of movement of the CTD package, as well as when the package decelerates due to ship roll, program DPDNB was used to read the SCS LOGGER raw data files and compute a fall rate every 60 scans (about 2 seconds). Fall rate was then carried along with the original unprocessed data. Program DLAGAV read the raw data files with fall rates and applied pre-cruise calibrations. Window outliers (acceptable ranges were -12 to 6500 db for pressure, -2 to 33°C for temperature, and 24 to 68 mmho/cm for conductivity) and first-differencing outliers (acceptable differences between scans were 1.0 db for pressure, 0.07°C for temperature, and 0. 1 mmho/cm for conductivity) were removed. Gaps in the data were filled by linear interpolation. DLAGAV lagged conductivity, edited data exceeding the fall rate criteria (minimum fall rate acceptable was 0.5 db/60 scans or about 15 meters per minute and pressure interval to skip beyond the point of failure was 1.2 db as determined at sea), and computed 1-decibar data files. First-differencing outliers were tentatively flagged if the differences between two scans were greater than the above mentioned preset values. If the difference between the next scan and the last good scan exceeded twice the allowable difference between scans, it too was flagged. If five scans in a row failed in this manner it was assumed that there was a gap in the data record and all scans were retained. Or if the next, third, fourth or fifth scan had values close enough to the last good scan, then the flagged scans were rejected. The filter applied to conductivity to account for the response time difference between the conductivity sensor and the slower platinum thermometer is described in Fofonoff et al. (1974). The conductivity is lagged as follows: C (n) = (I-A) CM (n) + A € C (n-1) where C is the lagged conductivity, CM is the measured conductivity, n is the scan number, and A is a constant empirically determined (Home and Toole, 1980) to best match temperature and conductivity (A = 0.87). Program EPCTD read calibrated pressure, calibrated temperature, and raw conductivity data output from DLAGAV. EPCTD corrected raw conductivity for thermal and pressure effects, applied conductivity calibrations, and computed salinity using the 1978 Practical Salinity Scale (UNESCO, 1981). Single-point spikes were eliminated using maximum allowable gradients of 0.05°C for temperature and 0.025 psu for salinity above 200 db, and 0.01°C for temperature and 0.0 1 psu for salinity below 200 db. Additional salinity spikes were omitted from casts 12, 24, 5 1, 58, 70, and 95 as specified by the processor. Missing data were filled by linear interpolation for a value to exist every whole decibar. Final conductivity values were recomputed from salinity. The conductivity cell dependence on temperature and pressure was corrected using the following (Fofonof et al., 1974): C = CR € (1-ALPHA € (T-15.) + BETA € (P/3.)) where CR is lagged conductivity, ALPHA is 6.5E-06, and BETA is 1.5E-08. EPCTD then calculated potential temperature, sigma-t, and sigma-theta using the 1980 equation of state algorithms described by Fofonoff and Millard (1983). Dynamic height in dynamic meters was calculated by integrating from the sea surface. When the uppermost pressure was not equal to 0 db, surface values of temperature and salinity were filled with the values associated with the shallowest pressure for which values did exist (provided this pressure was less than 10 db). EPCTD output finalized CTD data in PMEL's Equatorial Pacific Information Collection (EPIC) format (Soreide and Hayes, 1988). 6. DATA PRESENTATION The final calibrated data in EPIC format were used to produce the plots and listings which follow. The majority of the plots were produced using Plot Plus Scientific Graphics System (Denbo, 1992). Tables 2-6 define the abbreviations and units used in the CTD data summary listings. Plots and summary listings of the CTD data follow for each cast. Hydrographic bottledata at discrete depths are listed in the final section. 7. PERSONNEL Leg I Leg 2 John Bullister, NOAA Pacific Marine Environmental Laboratory (PMEL) CFC x David Wisegarver, (Chief Scientist, legs I and 2), PMEL CFC x x Fred Menzia, PMEL CFC x x Jeff Benson, PMEL CTD x Dana Greeley, PMEL C02/CTD x x Paulette Murphy, PMEL C02 x x Marilyn Roberts, PMEL C02 x x Linda Mangum, PMEL CTD x Kristy McTaggart, PMEL CTD x Lloyd Moore, NOAA Atlantic Oceanographic and Meteorological Laboratory (AOML) Nutrients x x Rick Van Woy, Scripps Institute of Oceanography CFC x Gary Wick, University of Colorado SST x x Mike Behrenfeld, Western Washington University (WWU) UV-b x Andrew Hanneman, WWU UV-b x Michael Mathewson, Woods Hole Oceanographic Institute Helium x Bob Byrnes, University of Southern Florida (USF) pH x Tanya Clayton, USF pH x Doug Wilson, AOML ADCP x Rick Cole, USF Moorings x Margie McCarty, PMEL CTD x Lt. Cliff Wilson, PMEL Moorings x Rolf Beck, Ocean Science Institute, University of Sydney CFC x Jeff Donavan, USF Moorings x 8. ACKNOWLEDGMENTS The assistance of the officers and crew of the NOAA ship Malcolm Baldrige is gratefully acknowledged. The survey department (Dennis Sweeney and Tom Lantry), under the supervision of Chief Survey Technician Robert Hopkins, provided valuable assistance in operations during this cruise. We wish to thank Margie McCarty for the acquisition and preliminary calibration of leg 2 CTD data, as well as Jeff Benson and Dana Greeley for their help with the rosette, bottles, and CTD operations. Funds for this program were provided to S. Hayes and D. Wilson by the Office of Global Programs. 9. REFERENCES Brown, N.L. (1974): A precision CTD microprofiler. Ocean, 74(2), 270-278. Denbo, D.W. (199-2): PPLUS Graphics, P.O. Box 4, Sequim, WA, 98382. Horne, E.P.W. and J.M. Toole (1980): Sensor response mismatch and lag correction techniques for temperature- sal in] ty profilers. J. Phys. Oceanogr., 10, 1112-1130. Fofonoff, N.P. and R.C. Millard (1983): Algorithms for computation of fundamental properties of seawater, UNESCO Report No. 44, 15-24. Fofonoff, N.P., S.P. Hayes, and R.C. Millard (1974): WHOI/Brown CTD microprofiler: methods of calibration and data handling. Woods Hole Oceanographic Institution Technical Report No. WHOI-74-89, 64 pp. Soreide, N.N. and SY Hayes (1988): A system for management, display and analysis of oceanographic time series and hydrographic data. Fourth International Conference on Interactive Information and Processing Systems for Meteorology, Oceanography, and Hydrology. American Meteorological Society, Boston, J20-J22. UNESCO (1981): Background papers and supporting data on the Practical Salinity Scale, 1978. UNESCO Technical Papers in Marine Science, No. 37, 144 pp. Figure 1. CGC-90-MB cruise track. Figure 2. Location of stations occupied during CGC-90-MB. Leg I stations are indicated by a circle, leg 2 stations are shown with a triangle. February 22 - April 16,1990 Pago Pago, Samoa - Wellington, NZ - Honolulu, HI Figure 3. CGC-90-MB upper ocean and deep water potential temperature (°C) sections along 170°W. Figure 4. CGC-90-MB upper ocean and deep water salinity (psu) sections along 170°W. Figure 5. CGC-90-MB upper ocean and deep water potential density (kg/m 3) sections along 170°W. Figure 6. CGC-90-MB upper ocean and deep water potential temperature (°C), salinity (psu), and potential density (kg/M3) sections along track from 60°S, 169.9°W to 49.5°S, 179.7°E. TABLE 1. CTD Cast Summary STN Cast Latitude Longitude Date Time W/D W/S Depth SST # # (GMT) (°T) (kts) (m) (°C) (db) Cast --- --- ---------- ----------- -------- ---- ----- --- ----- ---- ---- 0 0 14 53.2 S 170 8.5 W 23 FEB 90 1742 - - 4541 28.1 3013 1 1 14 59.5 S 170 0.6 W 23 FEB 90 2146 51 4 4806 28.2 200 2 2 15 0.1 S 170 0.3 W 24 FEB 90 151 - - 4817 28.8 4847 3 3 16 28.3 S 169 59.6 W 24 FEB 90 1238 - - 5073 28.6 2000 4 4 18 0.2 S 170 0.4 W 24 FEB 90 2149 148 7 4929 27.6 2001 5 5 20 0.2 S 169 59.6 W 25 FEB 90 816 180 8 5320 27.0 202 5 6 20 2.1 S 169 59.9 W 25 FEB 90 1100 - - 5361 27.0 2152 5 7 20 0.7 S 169 59.6 W 25 FEB 90 2049 116 10 5320 27.0 5427 6 8 21 9.1 S 170 1.7 W 26 FEB 90 657 120 10 5433 26.7 2501 7 9 21 59.5 S 169 59.8 W 26 FEB 90 1300 103 10 4839 26.0 2004 8 10 23 37.2 S 170 0.3 W 26 FEB 90 2310 98 18 5660 25.8 600 9 11 24 59.9 S 170 1.4 W 27 FEB 90 1157 90 20 5753 24.7 2501 9 12 25 0.4 S 170 0.5 W 27 FEB 90 1509 100 18 5702 24.6 600 9 13 25 1.3 S 170 0.9 W 27 FEB 90 1837 25 5 5712 24.6 5055 10 14 27 30.2 S 170 0.3 W 28 FEB 90 727 116 14 5223 24.1 352 10 15 27 30.8 S 170 0.9 W 28 FEB 90 952 114 10 5316 24.1 2500 11 16 30 0.3 S 170 0.8 W 28 FEB 90 2215 85 19 5417 23.7 304 11 17 30 1.1 S 170 1.5 W 1 MAR 90 16 67 18 5415 23.8 1512 11 18 30 0.3 S 170 2.6 W 1 MAR 90 441 60 16 5429 23.9 5178 12 19 32 31.0 S 169 59.9 W 1 MAR 90 1825 45 22 5588 22.1 351 12 20 32 34.2 S 169 59.9 W 1 MAR 90 2032 68 24 5577 22.0 1504 12 21 32 33.2 S 170 3.1 W 2 MAR 90 30 63 20 5568 22.0 5300 13 22 35 2.0 S 170 3.3 W 2 MAR 90 1514 15 18 5172 20.7 352 13 23 35 2.0 S 170 3.4 W 2 MAR 90 1719 15 18 5128 20.7 1503 13 24 35 1.4 S 170 0.6 W 2 MAR 90 2115 355 17 5225 20.7 5278 14 25 37 30.6 S 170 1.1 W 3 MAR 90 1037 55 12 5149 19.7 400 14 26 37 32.6 S 170 2.2 W 3 MAR 90 1252 40 18 5170 19.6 2504 15 27 40 0.0 S 170 0.2 W 4 MAR 90 52 38 14 4626 17.2 398 15 28 40 0.8 S 170 0.1 W 4 MAR 90 306 40 10 4626 17.6 2301 15 29 40 1.7 S 170 1.7 W 4 MAR 90 706 168 5 4626 17.6 4678 16 30 40 59.8 S 170 28.8 W 4 MAR 90 1535 192 10 4248 17.6 2005 16 31 40 58.1 S 170 29.0 W 4 MAR 90 1908 195 14 4323 17.5 4346 17 32 41 29.4 S 170 43.4 W 5 MAR 90 41 185 14 3984 18.0 3405 18 33 41 58.9 S 170 59.0 W 5 MAR 90 554 157 18 2974 18.2 2978 19 34 42 29.5 S 171 12.2 W 5 MAR 90 1016 161 10 1826 17.8 502 19 35 42 28.7 S 171 12.5 W 5 MAR 90 1225 155 6 1857 17.8 1845 20 36 43 30.1 S 170 51.2 W 5 MAR 90 1902 97 9 2904 15.6 2923 21 37 43 59.1 S 170 41.6 W 6 MAR 90 54 58 8 4473 16.0 4648 22 38 44 22.2 S 170 19.7 W 6 MAR 90 641 43 12 5108 15.8 5186 23 39 45 58.6 S 170 0.7 W 6 MAR 90 1612 25 8 5225 14.7 352 23 40 46 3.2 S 170 0.6 W 6 MAR 90 1819 25 20 5173 14.6 1752 23 41 46 2.7 S 170 0.1 W 6 MAR 90 2207 23 21 5190 14.6 5272 24 42 47 0.4 S 170 0.8 W 7 MAR 90 538 15 14 5252 13.4 3000 25 43 48 0.3 S 169 59.5 W 7 MAR 90 1133 8 14 5307 13.7 1000 25 44 48 1.3 S 169 54.9 W 7 MAR 90 1509 30 8 5294 13.7 5205 26 45 50 0.2 S 169 59.8 W 8 MAR 90 213 358 14 5340 12.5 404 26 46 50 0.3 S 170 1.5 W 8 MAR 90 434 315 10 5340 12.6 2402 26 47 50 4.0 S 170 4.2 W 8 MAR 90 844 321 25 5279 11.6 5305 27 48 51 59.6 S 169 59.2 W 8 MAR 90 2113 256 21 4981 9.5 1003 27 49 51 58.0 S 169 59.1 W 9 MAR 90 27 266 18 5054 9.4 5130 28 50 56 42.1 S 170 3.4 W 10 MAR 90 231 345 20 4883 5.5 1000 28 51 56 46.1 S 170 4.1 W 10 MAR 90 612 12 26 4822 5.5 4769 29 52 60 0.7 S 169 57.3 W 11 MAR 90 138 314 26 4139 3.8 1005 29 53 60 0.6 S 169 53.0 W 11 MAR 90 502 265 16 4139 3.8 4177 30 54 55 59.5 S 174 14.2 W 12 MAR 90 1825 155 10 5011 7.0 1001 30 55 55 59.8 S 174 10.1 W 12 MAR 90 2212 171 12 4970 7.0 5030 31 56 53 56.9 S 176 9.5 W 13 MAR 90 1304 270 24 5289 9.3 5025 31 57 53 54.2 S 176 3.3 W 13 MAR 90 1643 280 22 5310 9.2 1250 32 58 50 30.3 S 179 23.7 W 15 MAR 90 620 270 18 4448 10.2 1753 33 59 49 29.9 S 179 44.7 E 15 MAR 90 1420 337 18 2012 8.8 1987 TABLE 1. CTD Cast Summary (continued) STN Cast Latitude Longitude Date Time W/D W/S Depth SST # # (GMT) (°T) (kts) (m) (°C) (db) Cast --- --- ---------- ----------- -------- ---- ----- --- ----- ---- ---- 34 60 49 43.5 S 179 59.9 W 16 MAR 90 724 267 16 3111 8.5 3088 35 61 49 50.9 S 179 52.7 W 16 MAR 90 1146 284 21 4030 9.8 4056 36 62 50 29.0 S 179 21.4 W 18 MAR 90 704 285 22 4458 10.0 4531 37 63 46 20.0 S 179 28.9 E 20 MAR 90 5 145 14 3317 15.0 3004 38 65 34 38.9 S 178 38.2 W 29 MAR 90 948 144 23 6556 21.2 3000 39 66 32 29.8 S 178 18.8 W 28 MAR 90 2141 124 20 4994 21.9 5061 40 67 32 30.6 S 178 31.4 W 29 MAR 90 237 94 7 - 22.1 4219 41 68 32 29.8 S 178 44.6 W 29 MAR 90 704 93 10 3080 22.1 999 41 69 32 29.3 S 178 46.0 W 29 MAR 90 1000 100 11 2828 22.1 2973 42 70 32 29.0 S 178 30.1 W 29 MAR 90 1257 123 8 4211 22.0 1498 43 71 32 29.6 S 178 17.8 W 29 MAR 90 1554 157 8 5004 22.2 1500 44 72 32 29.5 S 178 0.2 W 29 MAR 90 2008 114 8 5722 21.9 1499 44 73 32 30.6 S 177 59.9 W 30 MAR 90 29 155 6 5898 22.0 5975 45 74 32 29.0 S 175 29.0 W 30 MAR 90 1229 125 4 5574 22.2 1498 45 75 32 29.4 S 175 30.1 W 30 MAR 90 1642 - - 5462 22.3 5526 46 76 32 28.8 S 171 28.7 W 31 MAR 90 1104 218 3 5182 21.6 5229 47 77 30 0.0 S 170 0.4 W 1 APR 90 233 134 12 5414 24.1 5502 48 78 24 58.6 S 170 1.3 W 2 APR 90 206 114 24 5689 25.4 399 48 79 24 58.9 S 170 1.0 W 2 APR 90 506 100 20 5784 25.4 2253 48 80 25 1.2 S 170 1.8 W 2 APR 90 857 122 21 5740 25.3 5804 49 81 22 29.8 S 170 0.4 W 2 APR 90 2222 135 25 5468 25.4 500 49 82 22 30.4 S 170 0.5 W 3 APR 90 42 126 20 5645 25.4 2999 50 83 20 0.4 S 170 0.4 W 3 APR 90 1333 125 22 5320 27.0 400 50 84 20 0.9 S 170 0.0 W 3 APR 90 1548 120 18 5351 27.2 2249 50 85 20 1.5 S 170 0.8 W 3 APR 90 1926 132 24 5502 27.2 5472 51 86 17 29.5 S 170 0.3 W 4 APR 90 841 117 25 4848 27.6 600 52 87 15 0.2 S 170 0.6 W 4 APR 90 2202 168 8 4686 28.5 399 52 88 14 58.7 S 170 2.9 W 5 APR 90 12 85 4 4771 28.5 2016 52 89 15 0.3 S 170 0.4 W 5 APR 90 438 105 14 4833 28.5 4873 53 90 11 26.4 S 169 36.5 W 5 APR 90 2237 329 10 5216 28.8 1250 54 91 10 6.1 S 169 30.2 W 6 APR 90 700 38 14 5249 28.9 5302 55 92 10 5.4 S 169 59.5 W 6 APR 90 1137 53 6 5161 28.8 1500 55 93 10 5.5 S 170 0.0 W 6 APR 90 1546 60 8 5163 28.7 5230 56 94 10 5.3 S 170 14.9 W 6 APR 90 2053 56 14 5929 28.7 5111 57 95 9 29.5 S 170 12.8 W 7 APR 90 238 75 16 4515 29.0 1499 58 96 5 0.1 S 170 0.8 W 7 APR 90 2307 64 20 5413 29.1 400 58 97 5 1.5 S 170 3.7 W 8 APR 90 139 93 19 5436 29.2 1998 58 98 5 0.8 S 170 1.2 W 8 APR 90 526 80 18 5280 29.2 5481 59 99 2 0.3 S 170 0.4 W 8 APR 90 2116 66 21 5214 28.4 998 60 100 0 59.7 S 170 1.2 W 9 APR 90 244 80 18 5435 28.3 1001 61 101 0 29.9 S 170 0.4 W 9 APR 90 605 90 16 5698 28.3 999 62 102 0 0.0 S 170 1.2 W 9 APR 90 931 78 15 5342 28.1 1999 62 103 0 0.7 N 170 0.3 W 9 APR 90 1149 69 10 5324 27.8 399 63 104 0 2.0 S 169 32.3 W 11 APR 90 916 72 13 5181 28.0 501 64 105 0 0.0 S 170 0.2 W 11 APR 90 1400 105 12 - 27.9 5582 65 106 0 30.0 N 170 0.3 W 11 APR 90 1837 104 14 5285 27.8 1002 66 107 1 0.1 N 170 0.3 W 11 APR 90 2145 117 16 5316 27.8 999 67 108 2 0.3 N 170 0.9 W 12 APR 90 308 96 14 5357 27.8 1001 68 109 5 0.1 N 170 0.6 W 12 APR 90 1655 90 22 7161 28.0 1005 69 110 5 13.7 N 169 52.4 W 12 APR 90 1923 60 20 5496 28.2 1249 TABLE 2. Weather condition code used to describe each set of CTD measurements. Code Weather Condition ---- ------------------------------------------- 0 Clear (no cloud) 1 Partly cloudy 2 Continuous layer(s) of cloud(s) 3 Sandstorm, dust storm, or blowing snow 4 Fog, thick dust or haze 5 Drizzle 6 Rain 7 Snow, or rain and snow mixed 8 Shower(s) 9 Thunderstorms TABLE 3. Sea state code used to describe each set of CTD measurements. Code Height (meters) Description ---- --------------- -------------- 0 0 Calm-glassy 1 0-0.1 Calm-rippled 2 0.1-0.5 Smooth-wavelet 3 0.5-1.25 Slight 4 1.25-2.5 Moderate 5 2.5-4 Rough 6 4-6 Very rough 7 6-9 High 8 9-14 Very high 9 >14 Phenomenal TABLE 4. Visibility code used to describe each set of CTD measurements. Code Visibility ---- ------------------ 0 <50 meters 1 50-200 meters 2 200-500 meters 3 500-1000 meters 4 1-2 km 5 2-4 km 6 4-10 km 7 10-20 km 8 20-50 km 9 50 km or more TABLE 5. Cloud type. Code Cloud Types ---- ------------------ 0 Cirrus 1 Cirrocumulus 2 Cirrostratus 3 Altocumulus 4 Altostratus 5 Nimbostratus 6 Stratocumulus 7 Stratus 8 Cumulus 9 Cumulonimbus x Clouds not visible TABLE 6. Cloud Amount. Code Cloud Amount ---- -------------------------------- 0 0 1 1/10 or less but not zero 2 2/10-3/10 3 4/10 4 5/10 5 6/10 6 7/10-8/10 7 9/10 8 10/10 9 Sky obscured or not determined