Influência das mudanças climáticas no regime pluviométrico em Erechim/RS no século XXI

Abstract

Changes in pluviometric regimes are caused by a number of factors, including natural sources such as temperature, air mass dynamics, sunshine, sea level, vegetation cover, relief forms; As well as human factors such as deforestation, urbanization, emission of gases that increase the greenhouse effect. Climate change directly influences precipitation, and the rainfall characteristics of a region can effectively contribute to the understanding of a possible change in the rainfall regime. The objective of this work was to evaluate the influence of climatic changes in the pluviometric regime in Erechim (RS) projected by climatic models for the 21st century. Daily rainfall data obtained from the HadCM3 / Eta / CPTEC - 20 km climatic model were analyzed to reproduce the behavior of the rains in the 20th century, as well as to verify the projection of rainfall by the model for the 21st century. Statistical tests (descriptive statistics, Pearson's correlation, Student's t-test) were applied to the observed data and those generated by the model to verify the model's ability to represent the past climate. The Mann-Kendall test was used to evaluate the trend of exit data from the climate model for the 21st century. The results showed that the HadCM3 / Eta / CPTEC model suggests an increase in precipitation, especially in autumn. The analyzes of the annual totals of the series 2011-2099 suggest an increment in the annual precipitations projected by the model. This increase may be associated with future climate change. The results demonstrated the importance of the use of regional models and the influences they present in relation to local characteristics.