FY 2002

Multiple anthropogenic tracer distributions in the ocean

Sabine, C.L., R.M. Key, J.L. Bullister, R.A. Feely, M.F. Lamb, F.J. Millero, R. Wanninkhof, T.-H. Peng, K. Lee, A. Kozyr, and N. Gruber

In Sixth International Carbon Dioxide Conference, Sendai, Japan, 1–5 October 2001, 915–918 (2001)

As a part of the JGOFS synthesis and modeling project researchers have been working to synthesize the WOCE/JGOFS/NOAA global carbon survey data to better understand carbon cycling in the oceans. Working with international investigators we have compiled a Pacific Ocean data set with over 35,000 unique sample locations analyzed for at least two carbon parameters. These data are being used to estimate the distribution of anthropogenic CO in the oceans. Parallel U.S. WOCE programs, conducted on the same cruises, have investigated the distributions of other anthropogenic tracers (e.g., chlorofluorocarbons and radiocarbon). This study examines the distribution of anthropogenic CO recently estimated for the Pacific Ocean (Sabine et al., 2001). The observed trends will be compared and contrasted with observed CFC and bomb C distributions in the Pacific. These three anthropogenic tracers have many similarities that are generally related to the large-scale circulation features in the Pacific. There are also several significant differences. Many of these differences can be attributed to the different atmospheric histories and equilibration times. The data-based distributions are also compared with results from the large number of global ocean carbon models that participated in the Ocean Carbon-cycle Model Intercomparison Project (OCMIP).