Variabilidade e tendência das chuvas no Estado da Paraíba.

Abstract

In this work rainfall time series of 54 cities had been used to estimate the variability and trend of rains in the Paraíba state. The mathematical models of the accumulated deviation and the statistical Mann-Kendall test had been used also. On the basis of the methodology had been elaborated possible rain scenes for the years of 2050 and 2100. The results had shown that the accumulated deviation gotten for the climatic microregions of the Agreste and Coast of the Paraíba state had been incoherent, since had been presented very negative, being of this form inadequate to analyze the variability of the precipitation in rainy areas. Already for the microregions of the Alto Sertão, Sertão and Cariri, the results had been coherent, since these microregions are likely the occurrence of extreme climatic rain events and of it droughts, it the reason to high variability of accumulated deviation of the precipitation. The standard deviation, the more values had been registered in the microregion of the Coast, varying it between 481.4 mm in the city of Santa Rita and 601.1 mm in João Pessoa; and the minors in the Cariri, oscillating between 189.9 mm in Cabaceiras and 273.3 mm in Monteiro. It was observed increasing and decreasing alternation of trends in some studied cities, prominence for the Brejo microregion that presented increasing rain trend in all the analyzed cities. In the prognostics of the precipitation, Alhandra, situated in the microregion of the Coast presented the prognostics highest. In this city the estimate of rains for 2050 is of 1791 mm and for 2100 is equal to 1962,6 mm. The microregion of the Cariri was the one that presented the lesser rain prognostics. The estimate for Picuí in 2050 is equal to 369,7 mm and; for São Sebastião do Umbuzeiro in 2100 is equal to 266,5 mm.