Validation of ECMWF sea level pressure analyses over the Bellingshausen Sea, Antarctica

Abstract

Surface pressure measurements from instruments deployed on ice floes in the southern Bellingshausen Sea were used to assess the accuracy of European Centre for Medium-Range Weather Forecasts (ECMWF) analyses in this region during February-May 2001. Despite the lack of in situ observations from this region. the analyses were found to be in very good agreement with the observed pressures and pressure gradients. The absolute difference between observed and analyzed pressures never exceeded 2.7 hPa over a pressure range of 965-1000 hPa. Standard deviations of the differences between observed and analyzed pressures were typically around 1 hPa. When additional in situ surface pressure observations from this region became available for use in the analyses, the agreement between analyzed and observed pressures improved only slightly. This suggests that atmospheric analyses are constrained well by satellite temperature soundings and other remotely sensed data in this region.