Abstract

As climate change and human activities continue to reshape the global water cycle, accurately assessing droughts has become increasingly challenging. Traditionally, drought assessments have relied on the assumption of “stationarity”—the idea that historical patterns of water availability remain stable over time. However, this assumption is increasingly invalid, as more than half of the world is now experiencing persistent declines in water storage. In a recent study, Nie et al. (2025) proposed a novel framework to address the growing uncertainties in drought evaluation under these evolving conditions.