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 similar to 0.5 degrees C warmer temperatures since 2002. The Alaskan Coastal Current, contributing about 1/3rd of the heat and 1/4 of the freshwater fluxes, also shows strong warming and freshening between 2002 and 2004. The increased Bering Strait heat input between 2001 and 2004 (> 2 x 10(20) J) could melt 640,000 km 2 of 1 m thick ice; the 3-year freshwater increase ( similar to 800 km(3)) is about 1/4 of annual Arctic river runoff. Weaker southward winds likely explain the increased volume flux ( similar to 0.7 to similar to 1 Sv), causing similar to 80% of the freshwater and similar to 50% of the heat flux increases.