Seasonal analysis of return periods for maximum daily precipitation in the Brazilian Amazon

Abstract

The aim of this study is to estimate the return period of maximum daily precipitation for each season of the year in different subregions of the Brazilian Amazon. For this, the extreme value theory was used, through the generalized extreme value (GEV) distribution and the generalized Pareto distribution (GPD). The GEV distribution and GPD were applied in precipitation series from homogeneous regions of the Brazilian Amazon. TheGEVandGPDgoodness of fit were evaluated by the application of the Kolmogorov-Smirnov (KS) test, which compares the cumulative empirical distributions with theoretical ones. The KS test results indicate that the tested distributions have a good fit, particularly the GEV distribution. Thus, they are adequate to study the seasonal maximum daily precipitation. The results indicate that extremes of more intense rainfall are expected during the rainy or transition seasons of each subregion. Using the GEV distribution (GPD), a daily total of 146.1 (201.6), 143.1 (209.5), and 109.4 (152.4)mm is expected at least once a year in the south, at the Atlantic coast in the Amazon catchment, and in the northwest of the Brazilian Amazon, respectively.