Assessment of precipitation trends in the sertão paraibano mesoregion

Abstract

The state of Paraíba, located in the northeastern region of Brazil, comprises 223 municipalities and covers an area of 56,469 km2. Paraíba is divided into four major mesoregions: Zona da Mata, Agreste, Borborema and Sertão Paraibano. For this study, the Sertão Paraibano mesoregion, a semiarid area, was chosen to understand vulnerability to climate change, taking into account the region’s economic importance for water and energy supply. The Mann-Kendall non-parametric test was applied to evaluate trends in the historical series of monthly, trimestrial, biannual and annual precipitation data. The series utilized corresponded to the period 1912-2012 and were built from data generated by five meteorological stations distributed throughout the mesoregion. These stations are maintained by the Executive Agency for Water Management (AESA) and National Department of Works Against Drought (DNOCS). The results indicated increasing precipitation trends for the Sertão Paraibano mesoregion, especially in the annual evaluation, for the first semester of the year (January to June), for the trimester December-January-February and the month of January, with slopes between 2.67 mm/year and 5.45 mm/year. The results evidenced the need to deepen studies on the influence of climate change in the area, to promote prompt adaptation measures.