PROBABLE RAINFALL TO THE MUNICIPALITY OF BOTUCATU-SP

Abstract

In the water balance of a place or region, rainfall is the main input element; therefore, knowledge of its availability is essential for the sustainable management of water resources. Probable rainfall is the extreme value (maximum or minimum) of rainfall that has a specific probability of occurrence and can be calculated through probability distributions. This study aimed to estimate the probable rainfall at levels of 10, 20, 30, 40, 50, 60, 70, 80, and 90% probability of occurrence for the municipality of Botucatu, SP, in cumulative periods of 10, 15, and 30 days, using the Gamma probability distribution. The Kolmogorov-Smirnov adherence test, at a 5% significance level, indicated that the Gamma distribution fitted the probable monthly rainfall in the municipality of Botucatu-SP and did not fit ten decennials’ periods and one biweekly period. Compared to previous studies, trend variations in rainfall were observed for Botucatu-SP, with a reduction in the period considered rainy and an increase in the period considered dry.