Carbon Dioxide, Hydrographic, and Chemical Data Obtained in the South Pacific Ocean (WOCE Sections P16A/P17A, P17E/P19S, and P19C, R/V Knorr, October 1992-April 1993
This data documentation discusses the procedures and methods used to measure total carbon dioxide (TCO2) and discrete partial pressure of CO2 (pCO2) during the three Research Vessel (R/V) Knorr Expeditions in the South Pacific Ocean. Conducted as part of the World Ocean Circulation Experiment (WOCE), the first cruise (WOCE Section P16A/P17A) began in Papeete, Tahiti, French Polynesia, on October 6, 1992, and returned to Papeete on November 25, 1992. The second cruise (WOCE Section P17E/P19S) began in Papeete on December 4, 1992, and finished in Punta Arenas, Chile, on January 22, 1993. The third expedition (WOCE Section P19C) started in Punta Arenas, on February 22 and finished in Panama City, Panama, on April 13, 1993. A total of 422 hydrographic stations were occupied during the three expeditions. Hydrographic and chemical measurements made along WOCE Sections P16A/P17A, P17E/P19S, and P19C included pressure, temperature, salinity, and oxygen [measured by conductivity, temperature, and depth (CTD) sensor], as well as bottle measurements of salinity, oxygen, phosphate, nitrate, nitrite, silicate, chlorofluorocarbon (CFC)-11, CFC-12, TCO2, and pCO2 measured at 4 and 20 C. In addition, potential temperatures were calculated from the measured variables.
The TCO2 concentration in 4419 seawater samples was determined with a coulometric analysis system; the pCO2 in 4419 discrete water samples was determined with an equilibrator/gas chromatograph system. At 114 stations, complete vertical profiles from the surface to the ocean floor were obtained, whereas at the remainder of stations only surface mixed layer samples were taken. In addition, 758 coulometric measurements for the Certified Reference Material (batches 12 and 13) were made. The shipboard analyses agreed with the Scripps Institution of Oceanography (SIO) manometric values within 1.2 Ámol/kg. The overall precision of TCO2 measurements is estimated to be ~▒2 Ámol/kg. The shipboard TCO2 measurements listed in this data report have not been corrected for the differences with the SIO manometric values.
The NDP consists of six oceanographic data files, two FORTRAN 77 data retrieval routine files, a documentation file, and the printed report, which describes the contents and format of all files
and the procedures and methods used to obtain the data.
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