Potential inertial effects in aeolian sand transport: Preliminary results

Most models to predict aeolian sand transport rates incorporate a threshold shear velocity term to specify the condition when sand flux begins. This term usually takes the form derived by the equation of Bagnold (1936). When shear velocity falls below the threshold value, the transport equations predict an immediate cessation of sediment movement. However, under some conditions this is not so and transport may continue for a period. This paper describes field observations of an inertia-like process that be considered when wind velocity fluctuates at near-threshold values. This study found that, although wind conditions had decreased to below threshold levels, transport was still taking place. Therefore using standard models that incorporate a threshold term, an underestimation of sediment transport would occur.