Mechanisms for the formation of eolian sand seas.

New evidence consisting, in part, of sand features visible on Landsat imagery of desert regions, and surface wind data from well-equipped weather stations, supports suggestions that geologically significant quantities of sand are blown long distances across modern deserts by wind action. Analyses of regional trends in direction and potential amounts of sand drift indicate that some present-day eolian sand seas are in zones of low total effective (sand-moving) wind energy along the general direction of sand drift in any particular region. These zones in which drifting sand can accumulate to form sand seas are created by interactions of topography and wind regime, or by changes in climate along the direction of sand drift. -from Authors