Evolutionary patterns of drought‐flood abrupt alternation events in the Yangtze River Basin, China

In recent years, compound extreme events have occurred with increasing frequency worldwide. A specific type of compound extreme event, drought‐flood abrupt alternation (DFAA), has been reported repeatedly, especially in China. Previous studies have revealed that DFAA events mainly occur in south‐eastern China. As the third largest watershed in the world, the Yangtze River Basin (YRB) is of strategic importance for China's socio‐economic development. DFAA events typically have negative impacts on agricultural production, the ecological environment, and other sectors. Therefore, this study investigates the evolutionary patterns of DFAA events in the YRB, aiming to quantitatively assess the impacts of climate change on one of China's major grain‐producing regions. The results indicate that the occurrence of DFAA events has increased over the past 6 decades, with the highest annual frequency rising from 3.5 to 7 times per year. Moreover, the average annual area proportion affected by DFAA events exhibits a statistically significant increasing trend ( p < 0.05) of 0.646% per decade. The intensity of DFAA events was also evaluated. These findings can inform targeted regulation of DFAA events in the YRB.