Premium
Variations in wind velocity and sand transport on the windward flanks of desert sand dunes
Author(s) -
LANCASTER N.
Publication year - 1985
Publication title -
sedimentology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.494
H-Index - 108
eISSN - 1365-3091
pISSN - 0037-0746
DOI - 10.1111/j.1365-3091.1985.tb00472.x
Subject(s) - sand dune stabilization , geology , wind speed , aeolian processes , wind direction , crest , transverse plane , geomorphology , sediment transport , prevailing winds , hydrology (agriculture) , sediment , geotechnical engineering , oceanography , physics , structural engineering , quantum mechanics , engineering
The magnitudes of increases in wind velocity, or speed‐up factors, have been measured on the windward flanks of transverse and linear dunes of varying height. On transverse dunes, velocity speed‐up varied with dune shape and height. For linear dunes, speed‐up factors varied principally with wind direction relative to the dune, with dune shape and dune height. The main effect of velocity speed‐up on the windward flanks of dunes is to increase potential sand transport rates considerably in crestal areas. This is greatest for large dunes, with winds of moderate velocity blowing at a large angle to the dune. Changing ratios of base to crest sand‐transport rates on transverse dunes tend to reduce dune steepness as overall wind velocities increase. On linear dunes, the tendency for crestal lowering is counteracted by deposition in this area when winds reverse in a bi‐directional wind regime.