ABSTRACT As part of the Synthesis and Modeling Project of the U.S. Joint Global Ocean Flux Study (U.S.JGOFS), this research team will compile data on the global distribution in seawater of dissolved inorganic carbon and the ratio of two carbon stable isotopes (13C/12C) to construct several models of oceanic carbon cycling and sea-air exchange of carbon dioxide. The data will be drawn from the 20-year dataset collected by the Scripps Carbon Dioxide Research Group and from other major ocean programs with a carbon dioxide component, especially U.S.JGOFS and WOCE (World Ocean Circulation Experiment). Such studies will allow estimates to be made of the oceanic capacity to take up anthropogenic carbon dioxide from the atmosphere. They are expected to improve our current ability to project global carbon dioxide trends into the next century.