2. Field Program

Ocean water samples were collected and analyzed at sea for the total CO2 concentration and pCO2 during a total of 152 days of the three WOCE expeditions, P-16S/P-17S, P-17A/P-17E/P-19S and P-19C, in the South Pacific Ocean, October, 1992 through April, 1993. The locations of 422 stations where samples were collected in the South Pacific Ocean by our group are shown in Fig. 1. In addition, the locations of CO2 measurements made by our group during these expeditions are also indicated in the figure. The total CO2 concentration in discrete water samples was determined using a coulometer, and the pCO2 using an equilibrator-gas chromatograph system. At 114 stations, complete vertical profiles from the surface to the ocean floor were obtained, while at the remainder of stations the measurements were made only in the surface mixed layer. A total of 4,419 water samples was obtained during the field phase of the investigation. The distribution of the measurements is summarized in Table 1.

Table 1. Summary of CO2 Determinations Made at Sea


Expedition
designations
No. of days
at sea
No. of seawater
samples
Total number
of analyses

P-16S/P-17S 51 days TCO2 1,549 ~1,700
pCO2 1,549 ~4,700
P-17A/P-17E/P-19S 50 days TCO2 1,282 ~1,440
pCO2 1,280 ~3,900
P-19C 51 days TCO2 1,588 ~1,850
pCO2 1,590 ~4,800
TOTAL 152 days TCO2 4,419 ~4,990
pCO2 4,419 ~13,400/