Sazonalidade da precipitação para a Amazônia usando o modelo REGCM3: avaliando apenas a forçante do Atlântico Equatorial

Abstract

The present study tries to bring a new perspective of the Equatorial Atlantic Ocean importance on seasonal pattern, during the summer and fall on the Amazon region. It contributes in a different way for studies in the area of climate modeling and variability of rainfall over the region. For this study, we used the model RegCM3 with Grell convection scheme, applying the donwscaling technique and using, as initial condition, NCEP/NCAR reanalysis data. After the simulations statistical method of the Bias was applied to evaluate how the accurately the model can reproduce the reanalysis seasonal rainfall. In a first analysis, it appears that the model is sensitive to FS or SAZC occurrences, as well as approaching the dynamics of the tropics and extratropics. The results suggest that the low resolution and the Grell parameterization are the main factors for inadequate quality of the simulations. Although the Grell scheme is suitable for areas with intense convection and strong vertical movements, an adjustment to the physical characteristics of the region is required. This study contributed to the improvement of regional climate models for the Amazon region, considering the contribution of ocean-atmosphere processes, during the summer and autumn in the southern hemisphere.