Interannual changes in the Bering Strait fluxes of volume, heat and freshwater between 1991 and 2004

Year-round moorings (1990 to 2004) illustrate interannual variability of Bering Strait volume, freshwater and heat fluxes, which affect Arctic systems including sea-ice. Fluxes are lowest in 2001 and increase to 2004. Whilst 2004 freshwater and volume fluxes match previous maxima (1998), the 2004 heat flux is the highest recorded, partly due to ~ 0.5oC warmer temperatures since 2002. The Alaskan Coastal Current, contributing about 1/3 rd of the heat and ¼ of the freshwater fluxes, also shows strong warming and freshening between 2002 and 2004. The increased Bering Strait heat input between 2001 and 2004 (> 2x10 20 J) could melt 640,000 km 2 of 1 m thick ice; the 3-year freshwater increase (~ 800 km 3 ) is about ¼ of annual Arctic river run-off. Weaker southward winds likely explain the increased volume flux (~ 0.7 to ~ 1 Sv), causing ~ 80% of the freshwater and ~ 50% of the heat flux increases. INDEX TERMS: 4207 General Oceanography: Arctic and Antarctic oceanography (9310, 9315); 4215 General Oceanography: Climate and interannual variability (1616, 1635, 3305, 3309, 4513); 4223 General Oceanography: Descriptive and regional oceanography; 4227 General Oceanography: Diurnal, seasonal, and annual cycles (0438).

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