A new study led by Prof. LI Zhi from the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences has revealed a troubling global increase in snow droughts under different climate scenarios. The findings were recently published in Geophysical Research Letters.
Snow droughts occur when there is an abnormally low snowpack for the season, classified as either "dry"- resulting from below-normal winter precipitation, or "warm"- caused by warmer temperatures that lead to rain rather than snow or early snowmelt despite normal precipitation levels.
Using ERA5-Land data and CMIP6 multi-model climate projections, the researchers analyzed long-term trends in snow drought frequency under various emissions scenarios. Their results show a marked increase in snow drought events through the end of the century. By 2100, snow drought frequency could triple under the intermediate SSP2-4.5 scenario and quadruple under the high-emission SSP5-8.5 scenario, compared to the 1981 baseline.
Notably, warm snow droughts are expected to dominate future trends. By 2050, they could comprise about 65% of all snow drought events. Under the SSP5-8.5 pathway, the frequency of warm snow droughts could rise 6.6 times, while compound dry-warm events-posing the greatest risk to ecosystems and water infrastructure-may become 3.7 times more common.
Moreover, snow droughts are shifting from dry to warm or dry-warm compound. Spatially, mid- and high-latitude regions are projected to experience more frequent and intense snow droughts.
These findings provide critical scientific insights to inform water security strategies and climate adaptation efforts worldwide.
