Deadly landslides are becoming more common and large amounts of rain are a known trigger. An atmospheric river is dumping rain out West. What you should know about your risk.
A storm of heavy rain, snow, and strong winds brought dangerous conditions to the Pacific Northwest this week. By Friday, up to 16 inches of rain could inundate Northern California.
The storm is what’s known as an atmospheric river, a long narrow strip heavy with moisture that slam into the mountains of the West Coast and dumps out prodigious amounts of rain.
While scientists haven’t concluded whether atmospheric rivers are increasing because of climate change, a warmer atmosphere, driven by the burning of fossil fuels, can hold more moisture, which can lead to increased extreme rain events. That increase in extreme rain events has likely caused more landslides, according to experts.
Fast-moving landslides called debris flows, which are mud and rock-laden torrents, are more common on land that has recently, and severely, burned, like wildfire-scarred regions. July’s Park Fire. the fourth largest fire in California history, happened in a region that could see up to 12 inches of rain and remains under a flood watch until Saturday morning, according to the National Weather Service.
So far, about a dozen small landslides, including one that resulted in a car wreck, have been reported in Northern California.