TOP: Mammoth Mountain ski patrolman Cliff Klock (right) and Forest Service member Jeff Karl (left) check their safety zone before firing a 105 mm howitzer to mitigate avalanche paths on January 8, 2017, at the top of the ski area in Mammoth Lakes, California. Photo: Brian van der Brug/Los Angeles Times/TNS. BELOW: An avalanche is seen on a mountain in Switzerland.