The US Forest Service thinks it knows what caused the boulder-filled mudslide that surged down Northern California's Mt. Shasta on Saturday: the Golden State’s extreme drought conditions. According to the LA Times, scientists think water gushed down from the Konwakiton Glacier, causing a mudslide that picked up increasing amounts of sediment and rocks before coming to a halt in Shasta-Trinity National Forest early Sunday morning. One resident who lives at the base of Mt. Shasta tells the Sacramento Bee, "I'd describe it as looking like chocolate pudding. It was just thick mud and boulders." This type of phenomenon, known as an outburst flood, can happen during hot, dry weather, when snow that usually buffers a glacier from the sun melts away.
That leaves the glacier vulnerable to the sun's heat, a retired UC Davis geologist tells the Times. Water pools up under or on top of the glacier until it spews out all at once, "almost like a cork in a bottle popping out suddenly," explains a Forest Service hydrologist. This type of glacial-melt flooding has occurred on Mt. Shasta before: A 1924 mudslide smothered a swath of land 5 miles long, a mile wide, and 10 feet deep. No injuries or severe damage were reported in this weekend's event—but how do locals who live close to the seven glaciers on Mt. Shasta feel about future possible outbursts? "You just have to accept whatever's going to be; it's just that simple," one resident tells the Record Searchlight. (The region's drought might end up being one for the ages.)