In arid mountain regions, snowpack is more than a winter climate indicator. It is a seasonal water reservoir. When snow water equivalent (SWE) falls below normal, meltwater supply, soil moisture, agricultural irrigation, and mountain-oasis systems can all be affected.
Xinjiang, located in inland Eurasia, relies heavily on snow and glacier meltwater. To examine frequent and spatially heterogeneous snow droughts in this region, researchers from the Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, analyzed snow droughts from 1980 to 2021 using the Long-term Series of Daily Snow Depth Dataset in China, ERA5 reanalysis data, and CMIP6 climate projections.
The study focused on the cold season from November to the following May and classified snow droughts according to SWE, cold-season precipitation, and thawing degree. Warm-only snow droughts were characterized by below-normal SWE with near- or above-normal cold-season precipitation, and their formation is often related to limited snow accumulation or earlier snowmelt under warming. Dry-only snow droughts were mainly driven by persistent cold-season precipitation deficits. Warm-dry snow droughts combined warming and precipitation deficits, usually lasting longer and showing larger SWE deficits.
From 1980 to 2021, Xinjiang experienced an average of about 23 snow drought years. Warm-only snow drought was the dominant type, with an average occurrence of about 10 years, followed by warm-dry snow drought at about 7 years and dry-only snow drought at about 6 years.
Snow droughts showed clear spatial heterogeneity. In northern Xinjiang, they were mainly distributed in the Altai Mountains, the northern slopes of the Tianshan Mountains, and the Yili River Valley. In southern Xinjiang, they mainly occurred in the Kunlun Mountains and the northern foot of the southern Tianshan Mountains. The Kunlun Mountains were a common high-frequency area for all three snow drought types, with most areas experiencing more than 20 snow drought years.
The temporal pattern changed around 2000. Before 2000, peak events of warm-only and dry-only snow drought were more prominent. After 2000, warm-dry snow drought coverage increased markedly, while dry-only snow drought generally declined and warm-only peak events became less frequent. This indicates that Xinjiang snow droughts are shifting from relatively single-driver events dominated by precipitation deficits or snowmelt anomalies toward compound processes driven by both warming and precipitation deficits.
Overall, the study draws three main conclusions. First, snow droughts in Xinjiang showed clear spatial heterogeneity during 1980-2021, with warm-only snow drought as the dominant type and the Kunlun Mountains as a shared hotspot for all three types. Second, after 2000, warm-dry snow drought coverage increased markedly while dry-only snow drought generally declined, indicating a shift toward compound warming-precipitation deficit processes. Third, the study identified a cold snow drought phenomenon that may be driven by snow sublimation, and future projections suggest that the southern Kunlun Mountains may face a high risk of snow drought and should be prioritized for snow drought monitoring and water-resource risk management.
See the article:
Zhu H, Cui P, Wang Y, Hao J, Chen G, Lin C, Li L. 2026. Classification, heterogeneity, and evolution of snow drought in Xinjiang under climate warming. Science China Earth Sciences, 69(7): 2611–2624, https://doi.org/10.1007/s11430-025-1964-6
Science China Earth Sciences
Data/statistical analysis