Outdoors modelling of snowdrift at SANAE IV Research Station, Antarctica

Abstract

This paper describes the experimental modelling procedure and results to evaluate the snowdrift characteristics surrounding the research station of the South African National Antarctic Expedition, SANAE IV. For this purpose a 1:25 scale model of the research station was constructed and mounted on a large flat snow covered area in the vicinity of the base. The wind profiles of the prevailing winds were measured with a 6-m wind mast positioned near the base model and the characteristic surface roughness and shear velocity functions were derived and analysed. Snow buildup was measured behind the scale model as well as the existing research station and a comparison was evaluated between the two, based on a similarity analysis. The similarity analysis method and results are presented in this paper. It is found that the surface roughness and shear velocity functions derived from the wind velocity data compares favourably with available results in literature for similar measurements of wind profiles in drifting snow conditions. From these results an inner law velocity relationship is established with additional parameters to account for the effects of surface roughness and saltating snow. It is further shown that the scaling parameters employed for the snowdrift modelling provide acceptable results when applied to outdoors modelling of snowdrifting.