For hydropower production at a global scale, Turner et al.  projected an uncertainty in the direction of change in global hydropower production to the tune of +5% to -5% by the 2080s, under a high- emissions scenario. On the other hand, van Vliet et al.  projected an increase in global hydropower production between +2.4% to +6.3% under RCP4.5 and RCP8.5, respectively, by the 2080s, as compared to a baseline period of 1971-2000, but with significant regional variations . For example, regions like central Africa, India, central Asia and northern high-latitude areas are projected to see more than 20% increases in gross hydropower potential . On the other hand, southern Europe, northern Africa, southern USA and parts of South America, southern Africa and southern Australia are projected to experience more than 20% decreases in gross hydropower potential. The Mediterranean region is projected to see almost a 40% reduction in hydropower production  . On the other hand, northern Europe and India are projected to add to their hydropower production capacity due to climate change by mid-century  .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report