Análise do índice de aridez da bacia hidrográfica do rio Piracuruca, Nordeste do Brasil

The objective of the study was to perform a statistical analysis and to characterize the Annual Average Precipitation (P), Potential Evapotranspiration (ETP) and Aridity Index (Ia) data in the Piracuruca River basin (PI-CE), as a way to know the areas with greater climatic rigor and subsidize environmental planning actions. Data from the Hydrological Information System (HidroWEB) of the National Water Agency (ANA) showed that: a) the highest rainfall totals are concentrated in the eastern part of the basin, influenced by the altitude of the Ibiapaba Plateau; b) the highest levels of ETP are concentrated in the Central-West sector of the basin, where the highest average annual temperatures occur; c) the highest levels of Ia are also concentrated in the Central-West sector, a section referring to the flattened areas of Piaui which present the lowest total precipitation and the highest values of ETP. These data should support subsequent studies and allow the development and implementation of adequate environmental planning.