<span>Land use change over Amazon Forest and its impact on the climate</span>

Abstract

This study describes the physical processes associated with the impact of the Amazon (AMZ) deforestation on the climate in the north-northwest sector of South America (SA). Two simulations with RegCM4, from 1979 to 2009, were carried out: one using a default land cover map (CTRL) and other one using deforestation scenario (LUC), i.e., all broadleaf evergreen trees tropical were changed by C3 grass. RegCM4 was integrated with a horizontal grid spacing of about 50 km and considering 18 sigma-pressure vertical levels for SA CORDEX domain. The lateral and boundary conditions for driving the model were obtained from the ERA-Interim reanalysis. The climate change signal due to AMZ deforestation was evaluated by comparing the climatology of the CTRL with the LUC experiment. AMZ deforestation causes a dipolar response in the precipitation consisting of reduced (increased) precipitation over western (eastern) side of the basin. Concerning the temperature, there is a warmer anomaly over the deforested areas, and it contributes to decrease the surface pressure. The higher air temperature is associated with an increase of the sensible heat flux and a decrease of the latent heat flux over the deforested areas.