Desempenho do método de desagregação de chuvas para determinação das relações intensidade-duração-frequência das precipitações em algumas localidades de Minas Gerais

Abstract

Heavy rainfalls are natural events, in general characterized by strong continuous precipitation over a short period. Precipitation can be characterized by three variables: intensity, duration and frequency. The relationship between them can be expressed by mathematical models called IDF equations. This work aims to evaluate the performance IDF equations generated from daily rainfall disaggregation technique using Gumbel distribution function, comparing them with the IDF equations adjusted by Pinto (1995) from recording rain gauges, for 28 rain gauge stations in the state of Minas Gerais. Daily rainfall used to establish the IDF relationships were obtained in the HIDROWEB information system, available on the website of the National Water and Sanitation Agency. The adequacy of the Gumbel distribution to the observed data was verified by applying Kolmogorov-Smirnov and Anderson-Darling tests. For the paired comparison between the precipitation intensities estimated by the IDF equations generated in this work and those obtained by Pinto (1995), the F test of variance was used. The intensities estimated by the generated IDF relations performed well when compared to the ones proposed by Pinto (1995) for the return periods of 5 and 10 years and duration of up to 60 minutes. For the return periods of 25 and 100 years, a good performance was found for times of up to 10 minutes and for the return period of 50 years, up to 25 minutes.