AVALANCHE

British Columbia, Yoho Park, Chancellor Peak

Leif-Norman Patterson (40) and his son, Thor (12), of Golden, and J.R. Saarinen (17) of Calgary set out to climb Chancellor Peak on 12 December 1976. Avalanche warnings had been posted in the area and the estimated depth of snow was 40 centimeters with unstable depth hoar. There was no new snow, a clear sky, a temperature of -2°C and a light wind. When they failed to return on schedule on 13 December, a search party went to find them. The victims had descended a gully on the northwest ridge of Chancellor Peak on foot and had been carried down by a dry slab avalanche which they probably triggered themselves. The avalanche started at an altitude of about 2400 meters and traveled about 600 meters on an average slope of 45 degrees. It was about ten meters wide, confined by the gully, and deposited a maximum depth of 1.5 meters. The three bodies were found at 1550 hours buried between 0.4 and 1.2 meters deep. (Source: Globe and Mail, Toronto, 15 December 1976; UNESCO Report on Destructive Avalanches.)

Analysis

Patterson was a very experienced climber with Himalayan experience. He chose to travel on 45-degree snowslopes where avalanche warnings had been posted. The slope indeed proved to be unsafe for travel. (Source: E. Whalley)