Arctic Ocean/Sea-ice Response to Climate Variability in a Coupled Model

Recent studies indicated dramatic changes of Arctic atmosphere, sea-ice and ocean. Historical sea level pressure data show a leading dynamic mode, the Arctic Oscillation, which is also close associated with the recent amplification of anthropogenic effects. Thinning and lessening of sea-ice, retreating of halocline and warming of ocean may attribute to AO and global warming. Because of lack of observations, numerical model is a good tool to explore sea-ice and ocean changes and variations. We developed a coupled Arctic ocean/sea-ice model with synchronously coupling scheme, which assure the energy and freshwater conserved. We used this model and carried out simulations forced by the NCEP/NCAR reanalysis data during 1948 through 1999. Results show dominant modes of sea-ice variability and recent decrease corresponding to the Arctic Oscillation and global warming. Sea-ice dynamics makes important contribute to sea-ice redistribution. The Barents Sea Branch of Atlantic Water plays important role in upper Arctic Ocean warming and the Eurasian Basin is a sensitive to the Atlantic water invading. Modification of Atlantic Water in the Barents Sea determines properties going into the Eurasian Basin and Arctic Ocean. Freshwater storage and export in the upper Arctic Ocean is also investigated.