A historic lack of snowfall in the western United States is sparking worries about water scarcity and wildfires in the upcoming summer. A recent study from Canada indicates that this situation may indicate a prolonged pattern that could jeopardize water resources for millions of people nationwide.
Snow coverage in the western U.S. is significantly below average for this time of year, marking the lowest levels observed since monitoring began in 2001 by NASA’s Terra satellite. The study, conducted by researchers at Concordia University in Montreal, reveals that the warming climate likely contributes to this trend. Between 2000 and 2019, the snow accumulation in Western Canada and its corresponding water content experienced a decline.
While the areas with substantial decreases only represent a small portion of the country, these declines impact the sources of major rivers in the Canadian Rockies. The study also notes minor drops in other parts of southern Canada, although these were not individually significant. Ali Nazemi, co-author of the study and Concordia’s associate engineering professor, highlighted that out of Canada’s 25 major drainage basins, 14 are experiencing effects from the declining snow conditions.
The diminishing snow levels have far-reaching implications, affecting municipal water systems, agriculture, lake levels, shipping, and the risk of wildfires in Canada’s forests. Kate Hale, an assistant professor at the University of British Columbia, likened the snowpack in mountainous areas to a natural water tower that stores and releases water when needed, especially during the summer for agricultural and human consumption purposes.
This year’s scant snowfall is disrupting the ski season at major resorts in the region, with several resorts in British Columbia having to suspend operations due to the lack of snow and warm temperatures. Vail Resorts, which operates ski facilities in both Canada and the U.S., reported one of its poorest early season snowfalls in the western U.S. Vancouver is also experiencing its first snow-free winter in over four decades.
The insufficient snowfall can be attributed to a “wet snow drought,” where precipitation, while near normal levels, falls as rain instead of snow. Alejandro Flores, a geosciences professor at Boise State University, explained that this phenomenon aligns with expectations in a warming climate, where rain increasingly replaces snow.
The reduced snow cover in the mountains acts as a vital water store, releasing water during the warmer months as it melts. This essential water source supports numerous ecosystems, including forests and water systems that millions depend on. Concerns persist about the potential earlier water stress in forests and heightened fire risks across North American forests due to the declining snowpack.
Nazemi’s team introduced a new metric, “snow water availability,” to assess the water content within the snowpack accurately. By utilizing satellite remote sensing technology, they analyzed data from 2000 to 2019 covering Canada and Alaska, identifying the most impacted watersheds, such as the Okanagan in B.C. and the Assiniboine-Red River basin in Manitoba. These declines could lead to reduced flows in major rivers like the Fraser and St. Lawrence Rivers, impacting water supply and hydropower generation.
Nazemi emphasized the historical impacts of dwindling snow cover on water security, citing past instances in 2015 where the Rocky Mountains experienced a significant winter snowpack decrease, leading to severe drought in central B.C. By studying these effects, experts aim to address vulnerabilities and adapt to changing water resource patterns to ensure sustainable water management practices.