Use of radar to assess aeolian processes

The interaction between wind and desert surfaces has important implications for sediment transport on Earth, Mars, and Venus, and for understanding the relationship between radar backscatter and aerodynamic roughness. Here, researchers report results from measurements of atmospheric boundary layer profiles, assessment of radar backscatter at P, L, and C wavelengths, and surface roughness in Death Valley, the Mojave Desert, and Lunar Lake, NV, and discuss the implications for aeolian process. The sites include playas, gravel and sand regs, alluvial fans, and lava flows. Boundary layer wind profiles were measured using anemometers at heights of 0.75, 1.25, 2.07, 3.44, 5.72, and 9.5 m; temperature sensors at heights of 1.3 and 9.6 m; and wind vanes at 9.7 and 1.5 m. Microtopographic measurements were made using a template and a laser-photo device to obtain RMS height. This study demonstrates that radar backscatter coefficients obtained from airborne and perhaps orbiting instruments could permit the derivation of aerodynamic roughness values for large areas. Such values, when combined with wind frequency data, could enable assessment of aeolian processes on a regional scale.