Influência da temperatura da superfície dos oceanos Pacífico Equatorial e Atlântico Tropical no regime de chuvas do estado da Paraíba.

Abstract

The Brazilian semiarid region has a rainy season of great climatic variability and rainfall irregularity, as a result of which there is a high probability of long periods of drought or torrential rains. This problem can be partially explained by increasing temperatures in the Atlantic and Pacific Oceans. Therefore, this study aims to verify if the zones of occurrence of the El Niño and Dipolo do Atlântico phenomena, if correlated in a lagged way with rainy periods of Paraíba rainy seasons, significantly influence the state's rain regime. Precipitation data were obtained through the Agência Executiva de Gestão das Águas do Estado da Paraíba – AESA and the Superintendência de Desenvolvimento do Nordeste – SUDENE, while Surface Sea Temperature data were obtained through the National Oceanic and Atmospheric Administration – NOAA website. Therefore, there was a screening, where only stations with pluviometric data considered regular were selected and then their respective precipitation climatologies were calculated. Then, Normalized Precipitation Anomalies and Normalized Anomalies of Surface Sea Temperature were correlated, and only those that obtained 1% or 5% of statistical significance, based on the t-student test. Six different wet periods have been identified across the state, ranging from four to eight consecutive months. In addition, it was found that the areas with the lowest and highest annual rainfall are, respectively, the Cariri/Curimataú and litoral areas. The lagged correlations were favorable to the remote influence of the El Niño and/or Dipolo do Atlântico areas in all regions of the state of Paraíba, acting significantly simultaneously in the regions of Alto Sertão, Sertão and Cariri/Curimataú, and in an isolated way by El Niño, in the other regions (Agreste, Brejo and Litoral).