A Numerical Study of Circulations Induced by a Dry Salt Lake

Abstract

Observations of surface winds in the vicinity of a moderate-sized (about 70 km2) dry salt lake by Tapper suggest that differences in albedo and soil thermal properties between the salt and surrounding sand surfaces may be strong enough to drive a mesoscale thermal circulation. In this paper a numerical mesoscale model is used to investigate disturbances generated by moderate and large-sized (about 7000 km2) lakes. In the latter case, a typical size for the great salt lakes of inland Australia, disturbances with strong horizontal and vertical shear are found at a distance of more than 200 km from the lakeshore by midnight. The separate contribution of albedo and soil property differences to the circulation are assessed, under both dry and moist soil conditions. The possible influence of such circulations on regional climate is discussed and it is suggested that salt lakes may be a source for solitary waves observed in the Australian interior.