This project is an observational and numerical study of the surface wind field of the Siple Coast, Antarctica. The antarctic surface wind field is highly irregular, is strongly affected by the surface slope, and has marked areas of convergence and divergence inland from the coastal margins. The interior provides large reservoirs of cold, negatively buoyant air which produce a persistent katabatic wind system. These convergent features appear to dominate the antarctic surface climate regime. This project will be located in the confluence zone upslope from the Siple Coast, which offers a different dynamical setting from earlier experiments in the Terra Nova Bay region of East Antarctica. In addition, the lower average elevation of West Antarctica allows synoptic disturbances to penetrate more deeply into the interior and to affect the surface outflow. Specific tasks to be undertaken are: (1) to describe and simulate both the downslope and cross-slope variations of the surface winds and temperatures in the Siple Coast confluence zone; (2) to describe and model the impact of synoptic forcing along the terrain slope on the behavior of the surface winds; (3) to investigate the interaction between the surface wind field and the potential temperature gradient along the snow surface, and (4) to measure and simulate boundary layer wind and temperature profiles along terrain contours under the opposing factors of mass convergence and decreasing terrain slopes.
