Abstract An unprecedented spatially compound heatwave‐flooding event (SCHFE) affected the Yangtze River Basin (YRB) and Northwestern South Asia (NWSA) during summer 2022, causing severe socioeconomic impacts. However, attributing such compound extremes remains challenging due to the lack of integrated frameworks that capture both physical causality and probabilistic assessment. Here, we introduce a storyline‐probability combined attribution framework to quantify individual contributions of atmospheric circulation, La Niña, and anthropogenic warming to this unprecedented 2022 SCHFE. Reanalysis and simulations show that La Niña generated large‐scale circulation patterns conducive to the SCHFE, amplifying the event's severity even when circulation anomalies were weaker than 2022. The SCHFE‐associated atmospheric circulation dynamics accounted for 49.21% (38.64%–59.41%) of the SCHFE's intensity and increased its likelihood by a factor of 4.5 compared with unrelated circulation. Anthropogenic warming contributed 42.31% (34.32%–49.85%) of the intensity throughout the thermodynamic effects, comparable to the circulation‐induced dynamic contribution, while also enhancing the occurrence probability of both La Niña and SCHFE. Projections further indicate that La Niña events will substantially elevate the probability of SCHFEs under continued warming. These findings underscore the need to incorporate atmospheric circulation, La Niña, and anthropogenic warming into early warning systems for such compound extremes.
Wang et al. (Thu,) studied this question.