Extreme Rainfall Events in the Longitudinal Profile Paraty (RJ) – Campos do Jordão (SP)

Abstract

The aim of this paper was to analyze the rainfall variability and their respective extreme values along the longitudinal profile SE - NW, among the municipalities of Paraty/RJ, Cunha/SP, Taubaté/SP and Campos do Jordão/SP. For that, was used secondary data of time series (between 1982 - 2002) for each locality. These time series presents values of accumulated daily rainfall; with these data, statistical techniques of central tendency analysis and box plot were applied. With the first method, were elaborated graphics of monthly averages and the maximum volumes of precipitation in 24-h; with the box plot method (quartile method), the statistical distribution of precipitation volumes and their respective extreme values, called outliers, were obtained. As a result, the analyzes pointed to a higher frequency of less intense rainfall along the longitudinal profile, but with occurrences of extreme events in 24h that exceeded by 138.9% the expected monthly averages. The central tendency analysis showed more generalized results, but was able to demonstrate the differences between the maximums in 24h and the monthly averages expected for each locality. With the box plot analysis, the results were more detailed, demonstrating more clearly the variability of the precipitation volumes throughout the time series, thus increasing the quality of precipitation distribution analysis.