The nocturnal boundary layer over the playa in Utah's West Desert

Desert playas such as Utah's West Desert are interesting laboratories for studying turbulence characteristics of the atmospheric boundary layer owing to very low roughness, albedo and elevation changes over large distances. In addition to surface homogeneity, during many months of the year, Utah's West Desert is dominated by fair weather conditions in which highly repeatable thermally driven winds are observed. In this presentation, we utilize a compilation of data taken over nearly a decade at the Surface Layer Turbulence and Environmental Science Test (SLTEST) facility at U.S. Army Dugway Proving Ground. We will discuss the characteristics of the nocturnal boundary layer turbulence and turbulence during transitions periods, as well as effects associated with the large thermal reservoir below the playa crust via modifications of the surface energy balance. Specifically, the time series of sensible heat and momentum fluxes will be quantified for each study period at varying heights. The objectives for each SLTEST study year differ, therefore a decade of data allows for a compilation of available data to understand the physical processes occurring at the SLTEST facility. When available, boundary layer height, surface energy balance and vertical profiles of mean temperature and wind speed will also be presented. The applicability of different turbulent scaling techniques will be evaluated over this highly idealized terrain.