The Inversion Wind Pattern over West Antarctica

Abstract

The surface windfield over the gently sloping interior ice fields of Antarctica is characterized by a high degree of persistence in terms of both direction and speed. The forcing of the surface wind is due primarily to the radiational cooling of the air adjacent to the sloping terrain. The representativeness of a simple diagnostic equation system in inferring the surface winds from a knowledge of terrain slope and temperature inversion structure is examined. Results suggest at least qualitatively accurate surface drainage patterns over the Antarctic continent are possible using this technique. A wintertime surface wind simulation for West Antarctica has been generated based on an accurate ice topography map. Close agreement is seen between the simulated surface windfield with field observations and sastrugi orientations. Implications of the simulation are discussed.