Sensibilidade da vazão gerada pelo modelo hidrológico smap em relação aos diversos metodos de estimativa da evapotranspiração

Abstract

This work evaluated the sensitivity of the flows generated by the SMAP rainfall-runoff model in the basin of the Banabuiú river, calibrated with data of the historical series of flow and precipitation of the period from 1912 to 2012, and the values of average monthly evapotranspiration estimated by 17 different Methods, using climatic data from the climatological norm of the Quixeramobim station. The mean annual evapotranspiration values were 1,697.2 mm / year, with a coefficient of variation of 0.42. However, the flows generated by SMAP for each evapotranspiration estimation showed little variation among them, with the exception of the Blaney-Criddle, Chapman Australian and Hamon methods, which estimated well below average evapotranspiration values. It was also evaluated the efficiency of the SMAP through the Nash-Sutcliff coefficient, which indicated good efficiency for all methods, except for the same three. It was concluded that the flows generated by the SMAP model are not sensitive to the method of estimation of evapotranspiration, and these can be used without great impact in the modeled flows, with the exception of those that underestimate the effect of evapotranspiration.