A Reconstruction of the Air-Sea Interaction Associated with the Weddell Polynya

Abstract A recent major climatic event was the occurrence of approximately 350 000 square kilometers of open water in the normally ice covered Weddell Sea near Antarctica during the winters of 1974–76. Within this polynya there was vigorous air–sea interaction resulting in the densification of the surface waters, a convective overturning of the water column, and the formation of large amounts of Antarctic Bottom Water. In order to further our understanding of this important event, the NCEP–NCAR reanalysis dataset is used to reconstruct the air–sea interaction associated with this polynya. The reconstruction shows that the polynya had a profound impact on the surface meteorology of the region. Surface air temperatures over the polynya were on the order of 20°C warmer than climatology. Total cloud cover over the polynya was 50% higher than climatology. The magnitude of the monthly mean sensible and latent heat fluxes during the winter months were on the order of 150 and 50 W m−2, respectively, while precipi...

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