Funds are requested for the investigation of radiocarbon and stable carbon isotope ratios and various other chemical properties in the major organic and inorganic carbon pools in the North Atlantic Ocean. Measurements will be made of dissolved organic and inorganic carbon (DOC and DIC) in a detailed profile collected at a site near Station S off Bermuda in the Sargasso Sea. In addition, the radiocarbon and stable carbon isotope ratios in specific organic components of the DOC (humic and labile constituents) will be measured. Suspended particulate organic carbon (POC) will be collected from 10 depth and sinking POC from 3 depth (1000, 2600 and 3600 meters at the same site. The goals of this project are to formulate the pathways that carbon follows in the open ocean water column of the North Atlantic, and to compare these results with those obtained earlier for the North Pacific. In particular, there is interest in determining the sources and time constants involved in the cycling of DOC, especially those which involves sedimentary organic carbon (SOC) and POC in the water column. The goals of this project is directly related to those of the Global Ocean Flux Study (GOFS).