Interannual variations and regionality of Antarctic sea-ice-temperature associations

In the Antarctic, climate-scale anomalies of surface temperature (T(s)) are associated with the atmospheric circulation and also sea-ice conditions. Negative (positive) anomalies of station T(s) tend to accompany more (less) extensive sea ice in broadly similar longitudes. However, the relationship between temperature and sea-ice conditions during large interannual variations of the circulation has been little explored, as has its association over longer distances within Antarctica. This study examines the inter-associations between T(s) at seven automatic weather stations in East Antarctica and the Ross Sea area, and sea-ice conditions in the sector 30°E eastward to 60°W for the three ice-growth seasons (March-October) of 1987-89. Strong between-year differences occur in the intercorrelations among station T(s), sectoral ice extent and the relationship between the two climate variables, especially for 1988 and 1989. These differences are also expressed in the patterns of cold-air mesoscale cyclogenesis over sub-Antarctic latitudes. The study indicates that the T(s)-sea-ice link is modulated strongly in the presence of large-scale interannual anomalies of the atmospheric circulation, including the El Nino-Southern Oscillation (ENSO).