Dust Emission Processes

Dust emission is governed by a combination of surface soil characteristics and processes that liberate dust from the soil. Researchers continue to improve upon estimates of soil crusting, moisture, and surface roughness that influence the threshold friction velocity required for particle entrainment. Many of these characteristics vary in space and time, making it difficult to characterize dust emissions over landscape, regional, or global scales. Saltation bombardment and aggregate disintegration play dominant roles in dust production and are emphasized in dust models. Recent research has reconsidered the roles of aerodynamic entrainment and eolian abrasion in dust emissions. While these processes tend to emit lower concentrations of dust, they do so over large spatial scales and thus may be important in total global dust emissions. Researchers are using field data to evaluate new dust emission schemes with the intent of improving emission estimates.