Large‐Scale Extreme Precipitation Events Increasingly Drive River Discharge Extremes in the Yangtze River Basin

ABSTRACT

Extreme precipitation events (EPEs) pose severe risks to society and the economy, and their spatial extent plays a critical role in shaping hydrological impacts. However, it remains unclear whether EPEs of different spatial extents have changed differently and how these changes affect hydrological extremes in the Yangtze River Basin. Here, we identify spatiotemporally contiguous EPEs in the Yangtze River Basin from 1960 to 2024 and classify them as small‐, medium‐, and large‐scale events. While small‐scale EPEs are the most numerous, they have declined significantly in relative frequency. In contrast, medium‐ and large‐scale EPEs have become increasingly common, with the latter becoming more intense. Despite accounting for only 1.1% of all events, large‐scale EPEs dominate annual maximum discharge across 23.3% of river reaches, and their contribution to discharge extremes has increased over time. Precipitation–temperature scaling further reveals that EPE intensity becomes more sensitive to warming as spatial extent increases, indicating a growing risk from widespread events in a warmer climate. These results highlight the spatial extent of EPEs as a key dimension for understanding changing precipitation extremes and basin‐wide flood risk under climate warming.