抄録
Large eddy simulations of dust devil-like vortices under various mean wind conditions were performed with the Weather Research and Forecasting model to investigate the effects of mean wind on the intensity and evolution of dust devils. It is shown that intense vortices are generated for all the mean-wind cases examined. Significant characteristics among the cases with the different mean winds are that vertical vortices are generated most preferably in medium-wind conditions in terms of their number and intensity, and that the lifetime of intense vortices becomes shortened with the increase in mean wind. It is also found that a stability parameter well describes the behavior of vortices in response to mean wind and provides a necessary condition for dust devil occurrence.