Climate Change and Hydrological Extremes

Climate change has profoundly impacted the Earth's atmospheric system and altered the terrestrial water cycle, reshaping the spatiotemporal patterns of hydrological extremes, including floods and droughts. This review aims to summarize recent advancements in understanding the response of hydrological extremes to climate change in both past and future.

Historical floods driven by heavy rainfall are increasing, while those dominated by snow processes are decreasing, resulting in non-significant changes on a global average. Previously overestimated droughts, due to inaccuracies in hydrological modules within offline diagnostic metrics, have been corrected by advanced modeling results, also revealing minimal historical changes on a global scale. Earth system simulations project concurrent increases in both floods and droughts under future climate change scenarios.

Climate change influences hydrological extremes across various scales, with diverse spatial distributions and underlying mechanisms. Decision-makers should integrate multi-source information to enhance the monitoring and adaptation of hydrological extremes, particularly focusing on abrupt drought-flood alternations.