Synoptic-Scale Weather Forcing of Surface Melt on West Antarctic Ice Shelves from 1987-2002

Given that the polar regions, especially West Antarctica, have experienced one of the largest temperature increases on Earth over the last few decades, an understanding of Antarctic climate has become more urgent. This work focuses on determining the underlying climatic processes controlling energy and mass balance over the ice shelf surface that are responsible for driving melting. This analysis examines surface melt extent in three regions: Ross Ice Shelf, Larsen Ice Shelf and the Amundsen-Bellingshausen Region over a 15-year time period. Self-Organizing Maps are used to categorize weather patterns for each December and January day during the study period, and the average surface melt extent for each SOM pattern is computed. These values are compared to average December and January surface melt extents for each region to determine which SOM patterns are associated with significantly greater or significantly less melt than the 15-year average. Over the Ross region, increases in Sensible and Latent heat fluxes are associated with higher surface melt extent, as is the presence of cyclonic circulation in the Ross Sea. In the Larsen and Amundsen-Bellingshausen regions, radiation fluxes are more closely associated with surface melt extent, though the relationship for the geographically diverse Amundsen-Bellingshausen region is less clear.