Surface Water in the Eurasian Basin of the Arctic Ocean

Reports results of re-appraisal and interpretation of data from 74 oceanographic stations (of >400 occupied), listed according to vessel and source. Surface water occupies the uppermost 200 m It is almost continuously supplied by continental runoff from Siberia which mixes with and collects saline water, to a few hundred times its original volume, as it crosses the arctic shelf seas. The surface water then flows directly to the exit from the basin between Spitsbergen and Greenland. Three layers of surface water are distinguished, on the basis of temperature and salinity features. Variations and ranges within each layer are thought the result of geographic location, presence of ice cover, seasonal changes, convection , and advection. Lowest layer, from 100 m down to the Atlantic water, shows evidence of mixing with the subsurface layer, as well as evidence of continuous replenishment. Prevalence of the cold subsurface layer in this basin is explained by a proposed model, which recognizes the submarine canyons, notably the Svyataya Anna in the Kara Sea, as important factors in mixing and cooling and as primary sources of subsurface water.