High-resolution simulations on the convective-scale transport of mineral dust in a fair-weather condition over arid regions are performed with a cloud-resolving modeling approach in a two-dimensional framework in order to investigate the role of boundary-layer dry convection on the vertical mixing and transport of dust. A diurnally-varying, fair-weather state is simulated by the cloud model by including full physics parameterizations with some simplifications, and the dust transport by convective motions is examined. Boundary-layer convective motion intensifies during the daytimes and induces surface dust flux through intensified surface winds. The boundary-layer top reaches up to the 4-km level, and the emitted dust is quickly mixed in the boundary layer. Although the simulated cloud activity is weak, further upward transport of dust above the boundary layer is achieved by cloud updrafts. The dust concentration in upper levels increases day by day through boundary-layer convection and sporadic cloud updrafts.
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