ANÁLISE DAS CAUSAS CLIMÁTICAS SOBRE O NÚCLEO DE DESERTIFICAÇÃO DE IRAUÇUBA-CE

Analysis of climate causes on the desertification nucleus of Irauçuba-CE

Abstract

Desertification processes in Brazil occur especially in areas of the Northeast and climatic conditions are the ones that most contribute to this. The main objective of this work was to analyze the possible climatic causes that influence the desertification process in Irauçuba-CE. For this, monthly precipitation and air temperature data for the municipality were used, provided by FUNCEME, for the period 1981 to 2020. The rainy season in Irauçuba comprises the period from January to April, with the month of March being the maximum month. precipitation record. The maximum precipitation is between 100 mm to 432.50 mm and the maximum temperature between 28.2°C to 29.9°C. There were more dry years than wet years. Decreasing trends in precipitation were detected, indicating that the rainfall that occurred in the locality has been decreasing gradually over time, with trends in the series of -0.9078. While the temperature tends to increase, with a trend in the series of 0.0833 without statistical significance according to the T-Student test. Wavelet analysis suggests that precipitation and temperature were influenced by the following scales: seasonal, extended ENSO, Sunspots and Atlantic Dipole, and the Pacific Interdecadal Oscillation influenced only the temperature series. In the cross-wavelet analyses, there was greater coherence at the 8-year scale, indicating that the maximum precipitation occurs 3 years before the Atlantic Dipole maximum.