Snow Drought Patterns and Their Spatiotemporal Heterogeneity in China

Abstract

This study presents a snow drought assessment method using snow water equivalent products to examine the patterns and differences in snow drought events in China from 1980 to 2020. The findings indicate that snow drought changes over the past 40 years can be categorized into three stages: The most severe snow drought occurred in the 1980s, followed by alleviation until 2009, and a subsequent aggravation after 2010. Light snow drought has the widest distribution and shows an increasing trend, whereas medium, heavy, and extreme snow droughts decrease gradually but show a decrease followed by an increasing trend over time. The distribution of snow drought in China displays significant spatial heterogeneity, with areas such as Alxa League in Inner Mongolia, Hami, Turpan, Bayingol, Xinjiang, and the Tibetan Plateau hinterland experiencing frequent snow drought events. Moreover, the low-altitude region has the largest average annual proportion of extreme drought, whereas the high-altitude region has the highest proportion of heavy drought. Among the three snow-dominant areas, Northern Xinjiang has the largest proportion of snow drought areas. The Northeast-Inner Mongolia has the highest proportion of extreme drought while the Tibetan Plateau exhibited abrupt changes in snow drought occurrence. These results contribute to a better understanding of the underlying mechanisms of snow drought changes, as well as serve as a foundation for the protection of the ecological environment.

Keywords

• China
• snow drought
• snow water equivalent (SWE)
• spatiotemporal characteristics