Sand flux simulations at a small scale over a heterogeneous mesquite area of the northern Chihuahuan Desert

Abstract

Within areas of the Chihuahuan Desert dominated by honey mesquite bushes (Prosopis glandulosa), soil erosion causes open eroded patches and the formation of large coppice dunes. The airflow patterns around the dunes and through the open areas are correlated with sand flux and erosion. This study uses wind velocity simulations from the Quick Urban and Industrial Complex (QUIC) model in combination with a sand flux parameterization to simulate sand fluxes for each of eight storms occurring in the springs of 2003 and 2004. Total sand fluxes based on the sum of all the sand collectors located within the study domain were usually within 50% of the measured values for each of the storms, with simulations for individual sand collectors also often within 50% of the measured values. Simulated fluxes based on two different sand flux parameterizations were generally within 10% of each other, differing substantially only when the sand flux was low (near the threshold velocity). Good agreement between the field observations with a Sensit instrument and QUIC simulations for the same location and time series suggests that QUIC could be used to predict the spatial and temporal variation of sand flux patterns for a domain. © 2007 American Meteorological Society.