Climate-driven snow drought set stage for deadly California avalanche, experts say

A deadly avalanche in the Sierra Nevada mountains of northern California, which killed eight backcountry skiers on Tuesday, is among the deadliest in US history. Experts say a climate-driven snow drought in the western US contributed to the conditions that caused the avalanche. Weeks of dry weather created a hardened snow layer, upon which several feet of new snow fell since Sunday. This new snow did not bond to the earlier layer, creating an unstable "storm slab." While authorities haven't determined the trigger, experts note that consistent snowfall throughout the winter could have allowed layers to bond more easily. Although one expert stated this specific avalanche was a meteorological phenomenon, scientists agree the record-low snowpack is linked to the climate crisis.

A deadly avalanche in the Sierra Nevada mountains of Northern California on Tuesday was triggered by unstable snow conditions. Experts attribute the avalanche to a recent "snow drought" followed by several feet of new snow. The dry period caused the existing snow layer to harden, preventing the new snow from bonding properly and creating a weak layer. The avalanche occurred near Lake Tahoe during a winter storm, trapping a group of backcountry skiers. At least eight skiers were killed, six survived, and one remained missing as of Wednesday. Authorities had issued avalanche warnings due to the increased risk following the heavy snowfall.