Two campaigns to measure transient tracers in the Atlantic Ocean (TTO/NAS and TTO/Equatorial) were funded by NSF during the period from 1980 to 1985. A complete data base for modelling this ocean basin would include a South Atlantic Study to: 1.Determine CO2 transports and their influence on world climate, 2.Constrain models of major ocean currents in this area, and 3.Confirm an observed 5-fold increase in the addition rate of new carbon to the thermocline. Eight components of such a study (SAVE) will be performed by investigators from LDGO, Princeton, University of Washington, WHOI, and SIO. The track record of these scientists is well established by successful completion of previous studies in the Equatorial and North Atlantic. They will provide physical and chemical expertise which will be directed toward a cooperative effort to reach the goals of the geochemical study. This component has the objective of providing large-scale distributions of He-3 and H-3 to assess ventilation mechanisms in the South Atlantic. About 2400 samples will be collected from surface, thermocline, intermediate, and bottom waters with highest sampling intensity in the upper layers. Dating of water masses from H-3/He-3 ratios will be made and interpreted along with other hydrographic and anthropogenic data from SAVE.