On the radiative effects of dust on tropical convection

[1] Radiative-convective equilibrium experiments with a two-dimensional cloud resolving model illustrate the influence of a lofted absorbing dust layer on the organization of tropical convection. At quasi-equilibrium, the dust-covered region of the model exhibits increased occurrence of deep convection compared to the dust-free region but with reduced convection in the dust-free region controlled in part by a large-scale monsoon-like circulation forced by the aerosol radiative heating. The dry air associated with the dust layer inhibits convection initially over most of the dust-covered region with convection occurring predominantly at the lateral boundaries of the layer. This behavior reproduces features which have been observed in cases of Saharan dust transport over the tropical Atlantic.

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