Distribution and fluxes of dissolved organic carbon in the Arctic Ocean

Dissolved organic carbon, from marine biota excretions and decomposing detritus, is one of the main components of the carbon cycle in the ocean. In this study, an attempt was made to construct maps of the distribution and fluxes of DOC in the Arctic Ocean and the exchanges with the Pacific and Atlantic Oceans. Because of the limited data available a multiple linear regression technique was performed to identify significant relationships between DOC (2200 samples) and hydrologic parameters (temperature and salinity), as well as depth, horizon, latitude and offshore distance. Mapping of the DOC distribution and its fluxes was carried out at 38 horizons from 5 to 4150 m depth (resolution 1°×1°). Data on temperature, salinity and meridional and zonal components of current velocities were obtained from the Ocean Re-Analysis System 4 (ORAS4) database. All these parameters were averaged for the June–October period, the season of water sampling. The import of DOC in the Arctic Ocean is estimated to be 206 ± 17Tg C yr−1, and the export is 194 ± 23Tg C yr−1, so the import–export is balanced within the errors