On the impact of aerosols on soil erosion

Abstract

[1] Soil erosion is a serious threat to agricultural productivity and the sustainable provision of food to a growing world population. No connection has hitherto been established between aerosols and rainfall-induced soil erosion on the ground. Here we use a cloud resolving model to simulate the effect of aerosols on rainfall erosivity (an indicator of the erosive potential of rain). Increased atmospheric aerosol concentrations tend to suppress precipitation in warm rain clouds, while in cold or mixed-phase systems, invigoration of surface rainfall can occur. We show that in both these cases, the response of erosivity to an increase in aerosol is in the same direction as, but amplified beyond the change in total rainfall. We also show that aerosols can impact erosivity through changes in raindrop size. Our results suggest that anthropogenic aerosol emissions affect erosivity and thus may have important consequences for agricultural productivity.