Efeitos da heterogeneidade da superfície na cobertura de cúmulos rasos.

Abstract

The objective of this study was to verify the influence of the soil cover on the shallow cumulus activity through mesoscale model simulations. For this study we used the BRAMS atmospheric model. Two simulations were performed for the Amazon region with two different soil cover type: one forested and other with some areas of forest replaced by pasture both with flat topography. The model was run for the time period from 1 to 10 October 2007. We verified that replacing some forested areas for pasture causes an increase of shallow cumulus cover over the domain as a whole. In the deforested areas whether the cumulus area increases or not depends on the atmospheric moisture and of the precipitation distribution as well. Air temperature, mixing ratio and surface fluxes are changed according to the precipitation distribution in each area. Our results suggest that an increase or decrease of the shallow cumulus cover depends on a wide variety of atmospheric conditions and the characteristic surface.