Avaliação de desempenho dos modelos do CMIP5 quanto à representação dos padrões de variação da precipitação no século XX sobre a região Nordeste do Brasil, Amazônia e bacia do Prata e análise das projeções para o cenário RCP8.5

Abstract

The global models of the Coupled Model Intercomparison Project Phase 5 (CMIP5) are evaluated over Northeast Brazil (NEB), the Amazon region and La Plata Basin regarding the representation of precipitation for the period 1901 to 1999. Furthermore, the projections of precipitation for scenario RCP8.5 for the XXI century are analyzed. The evaluation is performed using data from the Climatic Research Unit (CRU) and 20th Century Reanalysis V2 reanalysis of the National Oceanic and Atmospheric Administration (NOAA). The models are classified using indices that indicate how patterns of seasonal, interannual and decennial variation are represented. The evaluation identified CANESM as the best models for NEB, whereas for La Plata Basin, the French model CNRM_CM5_ r1i1p1 runs were superior. For the Amazon region, the model GISS Model-E2-R_r1i1p1 exhibited the best performance. Over NEB, most models indicate largest changes during the pre-season, but differ on the sign of the anomaly. In the Amazon region the models suggest greater chances of rainfall reduction up to 20.5%, 33.6 and 39.5% for the periods 2010-2039, 2040-2069 and 2070-2099, respectively. Over the La Plata region, the, ensemble projects few changes for the 2010 to 2039 period.