SS9.01 Ecosystem Science Practiced in an Urbanized Estuary: South San Francisco Bay Conaway, C, H, University of California at Santa Cruz, Santa Cruz, USA, conaway@etox.ucsc.edu Flegal, A, R, University of California at Santa Cruz, Santa Cruz, USA, flegal@etox.ucsc.edu   INVESTIGATION OF AIR-WATER EXCHANGE OF MERCURY IN SAN FRANCISCO ESTUARY In order to accurately characterize the air-water exchange of mercury in South San Francisco Bay, the concentration of surface water dissolved gaseous mercury (DGM) and total atmospheric total gaseous mercury (TGM) were measured at three sites in the estuary in April, May, and August 2003. The concentration of DGM averaged 0.150 ± 0.09 pM, which is similar to that observed in other contaminated estuaries, but nearly an order of magnitude lower than the previously reported average for San Francisco Bay. In addition, the data showed no distinct spatial variation or a temporal trend between months. Concentrations of TGM were supersaturated with and average of 2.1 ± 0.2 ng/m3 and showed little variation across the estuary. The resulting flux of mercury from the South Bay to the atmosphere is, therefore, estimated to be relatively constant at ~5 kg/y, at least during the spring and summer months.   Return to This Session's Schedule     Abstract Search