Estudo de alguns cenários climáticos para o Nordeste do Brasil.

Abstract

The main objective this study is to assess the current climate conditions in northeastern region of Brazil and to obtain same climatic scenery for 2050 and 2100 years, based on surface observations. It was used time series of air temperature (maximum, minimum and mean) to the 1961 and 2007 period, as well as climatological rainfall means of 88 stations in northeastern region of Brazil. The non-parametric test of Mann–Kendall was used to assess the statistical significance level of air temperature trend and also the software SEVAP was used to determine potential evapotranspiration, humidity index, aridity index and hydric index. The GrADS (Grid Analysis and Display System) was used to obtain the spatial distribution these variables on northeastern region of Brazil. Results showed an increasing trend in time series of air temperature statically significant by Mann-Kendall test for both studied period and the 2050 and 2100 sceneries. Both main and maximum air temperature has highest rate for studied period and for the 2050 scenery and a reduction between the 2050 and 2100 scenery. Minimum air temperature had higher amplitude and intensity than maximum air temperature. Increasing trends in potential evapotranspiration was observed in whole northeastern region of Brazil, mainly on central, west and north areas for two analyzed sceneries. The aridity and water indexes indicated an increased and the humidity index a reduction for two analyzed sceneries in northeastern region of Brazil, principally on the semi-arid area.