RAINFALL IN PAU DOS FERROS – RN

Abstract

The city of Pau dos Ferros, in the state of Rio Grande do Norte, is located within the rainiest semi-arid region on Earth, presenting an average annual rainfall of 772 mm (1911-1990). There is high spatial and temporal variability, as a large part of this rain occurs in the first half of the year, especially from February to May, although in some years this may not happen, characterizing droughts. In order to determine the rainfall characteristics of this municipality, data provided by EMPARN were used for a thirty-year period, from 1987 to 2016. From 2014 onwards, due to data gaps, the regional weighting method was applied to fill these gaps and complete the series, using data from up to eight neighboring rain gauge stations. From these EMPARN data, it was possible to apply the statistics described by calculating the central and dispersion measures, as well as their frequency distribution, using spreadsheets in Excel software. It was also possible to obtain an average number of days per year with recorded precipitation (equal to or greater than 1 mm). Most years showed rainfall below the average calculated for the period, which was 695.4 mm. The number of days with recorded precipitation per year was 52, of which 36 were during the rainy season, and in most years this number was below average both during the rainy season and for the year as a whole.