The present study is a case study of two events El Niño through regional climate modeling. The goal is to subjectively evaluate the performance of the regional climate model simulations RegCM4 to represent the seasonal patterns of rainfall during the rainy season over the Amazon for two El Niño events recorded in 1998 and 2010 . The observational data used were from the TRMM satellite rainfall and monthly SST and OLR . We use the fourth version of the Regional Climate Model ( RegCM4 - Regional Climate Model version 4 ) integrated in El Niño years with three convective parameterization schemes : Grell - Fritsch with lock Chapell , MIT - Emanuel and Tiedke , in order to verify which scheme best represents the
observed data . The results showed the presence of intense SST anomalies reaching values 2-3 ° C in both events . It also showed the absence of the dipole of the Atlantic Ocean and this is his contribution through the mass shift in favor of the occurrence of rainfall in the study region , through the subtropical high , positive OLR anomalies over the Amazon inhibiting the formation Cloud in a certain part of the region . Of the three convective schemes MIT - Emanuel showed the best performance compared to the observed data , Grell comes next , but much overestimated precipitation values for certain periods and Tiedke contrary , very underestimated in all periods . The states of Pará , Amazonas, Acre, Amapá and Tocantins, were well represented in relation to their characteristics of seasonal rain. Importantly, the present study was merely an analysis of two cases, therefore, it is not appropriate to generalize these results to all El Niño events , more simulations and more cases are needed to deepen the
analysis .
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