Cm. Neuman et al., The effect of unsteady winds on sediment transport on the stoss slope of atransverse dune, Silver Peak, NV, USA, SEDIMENTOL, 47(1), 2000, pp. 211-226
Rapid (10 s) measurements of sediment transport and wind speed on the stoss
slope of a transverse dune indicate that the majority of sand transported
is associated with fluctuations in wind speed with a periodicity of 5-20 mi
n duration. Increases in the sediment transport rate towards the dune crest
are associated with a small degree of flow acceleration. The increase in w
ind speed is sufficient, however, to greatly increase values of the intermi
ttency index (gamma), so that the duration of saltation is extended in cres
tal regions of the dune. The pattern of sediment transport on the stoss slo
pe and, therefore, the locus of areas of erosion and deposition change with
the regional wind speed. Erosion of the crest occurs during wind speed eve
nts just above transport threshold, whereas periods of higher magnitude win
ds result in deposition of sand upwind of the crest, thereby increasing dun
e height. Although short-term temporal and spatial relations between sand t
ransport and wind speed on the stoss slope are well understood, it is not c
lear how these relations affect dune morphology over longer periods of time
.