Three of the four carbon chemistry properties in seawater will be determined during the JGOFS time-series expeditions in the Central Equatorial Pacific Ocean, which have been scheduled for March 1992 and November 1992, a total of 67 days at sea. The total inorganic carbon concentration will be determined using an automated coulometric system; the CO2 fugacity using an equilibrator/infra-red procedure; and the total alkalinity using the potentiometric acid titration. The total inorganic carbon and the total alkalinity will be measured at sea in discrete seawater samples collected throughout the water column at the time-series stations. Furthermore, the measurement of these three parameters in surface seawater will provide the means to critically evaluate the consistency and reliability of each of these data sets. The accuracy of both total CO2 and total alkalinity will be controlled by measuring reference solutions by A. Dickson. The processed data will be (1) quality controlled according to the criteria that soon will be established by the DOE sponsored committee responsible for CO2 data quality management, (2) tabulated and added to the JGOFS data base for distribution to the scientific community, and (3) used in conjunction with associated measurements both to give a descriptive account of the results and to quantify the processes involved in the spatiotemporal variations of the properties of the oceanic carbon cycle.
