Impacto dos cenários de mudanças climáticas e demandas consuntivas no desempenho dos reservatórios do rio São Francisco, Brasil

Abstract

Climate change in the coming decades could intensify extreme events such as severe droughts. Added to the possible increase in water demands, they can exert great pressure on hydrosystems. To confirm this assumption, a set of scenarios to consider climate change and the growth of water consumption demand were proposed in this study, with the aim of evaluating how each demand may increase and its impact on performance in the four main multipurpose reservoirs of the São Francisco river. To this end, five recently launched global climate models were used, with two climate change projection scenarios, SSP2-4.5 and SSP5-8.5. The natural affluent and withdrawal flows were estimated for the reservoirs considering all existing, new and projected demands. The conjunction of scenarios indicated an increase in Potential Evapotranspiration, a possible significant reduction in water availability, an increase in consumption demand, especially for irrigation, and a reduction in the performance of all analyzed reservoirs.