Continued Investigation of the Extraordinary Katabatic Windsat Terra Nova

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This project is a continuation of a successful investigation into the antarctic surface and boundary layer wind field, with specific emphasis on the extremely strong down-slope katabatic winds in the vicinity of Terra Nova Bay. The outward flowing surface air is an integral part of the meridional circulation, together with inflow and convergence aloft, and generally sinking motion over the continent. The pattern of katabatic winds over the sloping ice sheet is highly irregular, with air converging into several narrow coastal regions to produce locally what are recognized as the strongest and most persistent surface winds in the world. Known examples are at Cape Denison and Port Martin in Adelie Land (facing Australia), and in Terra Nova Bay on the western coast of the Ross Sea. Specific tasks to be undertaken as part of this project are to complete the kinematic, dynamic, and climatological analysis of specific katabatic events, to integrate high resolution satellite imagery into specific case studies, and to carry out extensive numerical modeling at various spatial scales. An existing array of automatic weather stations has provided the primary data set for this study; it is being extended by the satellite imagery which will be used to investigate the offshore propagation of the katabatic air stream. The modeling effort is being extended to continent-wide simulations using a grid spacing of 40 kilometers in order to explore the climatic impacts of the coastal confluence zone dynamics.