Seasonal distribution of dissolved inorganic carbon and net community production on the bering sea shelf

Abstract. In order to assess the current state of net community production (NCP) in the southeastern Bering Sea, we measured the spatio-temporal distribution and con-trols on dissolved inorganic carbon (DIC) concentrations in spring and summer of 2008 across six shelf domains de-fined by differing biogeochemical characteristics. DIC con-centrations were tightly coupled to salinity in spring and ranged from ∼1900 µmoles kg−1 over the inner shelf to ∼2400 µmoles kg−1 in the deeper waters of the Bering Sea. In summer, DIC concentrations were lower due to dilution from sea ice melt, terrestrial inputs, and primary production. Concentrations were found to be as low ∼1800 µmoles kg−1 over the inner shelf. We found that DIC concentrations were drawn down 30–150 µmoles kg−1 in the upper 30 m of the water column due to primary production and calcium car