A revival of climate-projected hydropower potential at the Three Gorges hydropower station driven by migrated global warming hotspots

Developing hydropower offers a prospect to mitigate both anthropogenic climate change and air pollution; however, the benefits of development are susceptible to the changing climate, and large uncertainties remain in projections of future hydropower potential (HP). Here, we show that climate-projected HP of the Three Gorges hydropower station (TGHS), the globally largest hydropower station and China's dominant renewable energy producer, declined significantly (−1.6 TWh/decade) over 1948–2006. Conversely, TGHS HP increased drastically (16.9 TWh/decade) since 2006, although the climate warming trend continues. Reanalysis datasets confirm that elevated tropospheric warming occurred over tropical Asian regions during 1948–2006, stimulating a quasi-stationary Rossby wave that caused the decline. However, the warming hotspots migrated northward to subtropical regions after 2006, inducing revived runoff and thus the climate-projected TGHS HP trend. Our results provide potential causes for the uncertainties of the projections from climate models and help improve the projections of regional hydropower changes.