Scaling Laws in Aeolian Sand Transport Under Low Sand Availability
Sandesh Kamath, Yaping Shao, Eric J. R. Parteli
Abstract
Abstract Previous studies of wind‐blown sand have considered either fully erodible or non‐erodible soils, but the transport over sparsely sand‐covered soils is still poorly understood. The quantitative modeling of this transport is important for parameterizing Aeolian processes under low sand availability. Here we show, by means of numerical simulations, that the sand transport rate Q scales with the wind shear velocity u ∗ as , where u ∗t is the minimal threshold u ∗ for sustained transport, d is particle size, g is gravity and ρ f is air density, while u ∗t and the empirical parameters a and b depend on the sand cover thickness. Our model explains the transition from the quadratic to cubic scaling of Q with u ∗ as soil conditions change from fully erodible to rigid and provides constraints for modeling Aeolian transport under low sand availability.