Eolian features shaped by aerodynamic and vorticity processes

Abstract

This chapter describes the eolian features shaped by aerodynamic and vorticity processes. Eolian features have a variety of shapes because numerous factors are involved in their formation. One important factor is wind regime, and simpler the wind regime, more likely the streamlined forms develop. The wedge-shaped snow drift, fashioned by concurrent deposition and erosion, is one of the most beautiful shapes in nature. Formed by winds that strip snow from fields, these drifts—which develop by the million—move obliquely across ditches, gutters, and snow banks. These drifts are often formed as resultants between the main wind and that of a deflected flow. It has been observed that once the drifts are formed, their shapes then guide the local flow, which in turn governs subsequent minor changes. Some drifts have inclined crest lines, but on others a considerable portion of the crest line is horizontal, becoming inclined only where the feature narrows leeward in the closure of streamlines over the crest. It is found that closure brings these flow lines closer to the interface, and they begin to create coarse fluting on the sides and across the lee keel. © 1983, Elsevier Science & Technology. All rights reserved.