Space-time variation of the climatic water availability in the state of Goiás, Brazil

Abstract

This study sought to evaluate the climatic water availability in the State of Goiás, Brazil, from precipitation data, with probability of 75%, and evapotranspiration potential data. The Geographical Information System was used, which besides carrying out the operations of georeferenced data on precipitation and evapotranspiration, allowed the spatialization of climatic water availability. The results obtained showed that the State is characterized by two well-defined climatic seasons: one, rainy, with an excess of precipitation, and the other, dry, with an almost complete lack of rain and marked by a water deficit. The water excess verified in the rainy season follows a spatial tendency which decreases in importance from Northwest to East and from North to South. Divided into classes with 20 mm intervals, the water excess resulted in a very heterogeneous spatial distribution, while the water deficit, with a lesser range of variation, showed a more homogeneous spatial variation.