Análise hidroclimatológica da seca no sistema hídrico Armando Ribeiro Gonçalves: implicações para o monitoramento e gestão dos recursos hídricos

Abstract

Water is a fundamental factor of human life and the study of its dynamics is essential to understand the relationship we have with it and to deal with the different levels of access of the population to this resource. Drought is a central issue in regions that suffer from this phenomenon, which is complex to understand and frequent in the Brazilian Northeast. Its complexity involves society, hydroclimatology, economy and ecosystems. Droughts cause great damage to the population, which relies on reservoirs for a significant part of its water availability. These reservoirs are an important instrument of water security in the region and need to be monitored more closely. Studies on the relationship between drought, especially hydrological drought, and the deficit in these aquatic environments are still scarce. Finding ways to live with droughts and their impact on the maintenance of water reserves is crucial for the rational use of water. The objective of this study was to analyze the hydroclimatology in the reservoirs of the semi-arid region, more precisely in the water system of the Armando Ribeiro Gonçalves reservoir, located in Itajá-RN, by identifying droughts of different durations. To this end, historical series of precipitation and potential evapotranspiration data were used to calculate the SPEI (Standardized Precipitation Evapotranspiration Index) drought index at different time scales, correlating them with reservoir data and their stored volume anomaly, in order to understand their hydroclimatology and their hydrological drought periods. In the end, it was concluded that the drought indices usually used to diagnose short-term droughts, such as meteorological droughts, which have short-term effects, should be used with caution, as they are not very efficient for monitoring longer-term drought that affect water reserves - hydrological droughts. The study showed that the best correlation results between the drought index and the stored volume anomaly were for the SPEI-42. This indicator showed a satisfactory response to the onset of hydrological drought and can serve as an important tool for monitoring and managing water resources.