Análise geoestatística para o estudo da variabilidade espacial de extremos da precipitação na bacia hidrográfica Piancó-Piranhas-Açu

Abstract

This study aims to analyze the spatial variability of precipitation in the Piancó-PiranhasAçú (BHPPA) through methodologies based on Geostatistics. During the work, theoretical and conceptual conceptions about extreme weather precipitation, possible environmental impacts, and socioeconomic impacts. In addition, steps were discussed how the role of Geostatistics in the study of the spatial variability of precipitation, capturing the degree of spatial continuity of accumulated annual precipitation. Among the available methodologies, it was used the Ordinary Kriging and Indicator, which are two techniques of Geostatistical interpolation widely used for spatial interpolation. With Ordinary Kriging, the spatial variability of precipitation was mapped. With the Ordinary Kriging mapped the spatial variability of annual precipitation, and with the Kriging Indicatrix mapped the spatial variability of the risk of rainfall. With Ordinary Kriging we mapped the spatial variability of annual rainfall, and with the Indicative Kriging we mapped the spatial variability of the risk of extreme rainfall events in the BHPPA, through the percentiles. Finally, it was found that the rainiest four-month period with the distribution corresponded from January to April, with the peak in March rainy months included May, June and July, and the driest months were from August to November. In addition, it was also found that the driest areas are to the north of the basin, in Rio Grande do Norte together with the extreme eastern part of the Seridó Paraibano, moving westward, in the central region one finds accumulations of and finally, at the end of the westward direction are the largest rainfall accumulations. accumulations of precipitation. Thus, it was observed that precipitation is a variable that has spatial continuity, that is, it varies gradually and continuously over a geographic area.