Classification and Attribution of Compound Flood Events

Floods are the most common natural hazards, and the compound effects of flood events pose severe challenges to flood protection. The lack of flood observation data makes it difficult to identify and analyze compound flood effects. Here, we employed a data-driven approach to reconstruct discharge in ungauged regions. We classified flood events from a compound perspective, quantified the contributions of different drivers, and compared the impacts of compound and non-compound flood events. Our results showed that pronounced compound effects were common in most flood events, with many compound flood events clustered in India and southeastern China. Compound events caused substantially greater impacts than non-compound events in Asia and North America.