Monin-Obukhov similarity (MOS) theory has been a widely applied approach for estimating turbulent fluxes of heat and momentum in the surface layer and is used exclusively by Soil-Vegetation-Atmosphere-Transfer (SVAT) models for simulating surface-atmosphere process. However, a number of studies have shown significant discrepancies between turbulent fluxes derived from MOS and measured directly by eddy covariance for rough and heterogeneous surfaces (e.g., Chen and Schwerdtfeger, 1989).

In this paper, we discuss the applications of MOS using mean profiles of temperature, 0, and wind speed, u, for estimating sensible heat and momentum fluxes over a mesquite dune site in the USDA-ARS Jornada Experimental Range near Las Cruces, New Mexico. The site contains complex topography and heterogeneous cover where 0.5 m tall mesquite vegetation grow on dunes that are 1-2 m in height and ~10 m in width. Distances between dunes are on the order of 20 m. Very little if any vegetation exists in this interspace region.