Crevasses are the greatest danger facing those who climb or ski on active glaciers. As the glacier is pulled relentlessly downhill by gravity, large cracks develop in areas where the ice is under tension. These crevasses can be hundreds of feet deep and tens of feet wide on large, active glaciers. Deep winter snows can cover up the crevasses, usually by forming snow bridges which may completely hide the crevasse by spring. But the hidden danger lurks, waiting for a traveler to step through a sun-weakened snow bridge into the cavernous depths below.
The safest method of traveling on glaciers involves roping up in groups, preferably of three or more. In case of a crevasse fall by one person, the others on the rope team can haul the victim up the surface using any of several standard pulley systems. Each member of the team must carry the necessary equipment, and must have practiced using it before any glacier trip. Skis can also reduce the likelihood of crevasse falls, since a person's weight is more evenly distributed across the snow than on foot, relieving stress on fragile snow bridges.Some useful books about glaciers and safe glacier travel:
|Glacier Travel & Crevasse Rescue. Andy Selters; The Mountaineers, Seattle, 1993, 100 pp.|
|Mountaineering: The Freedom of the Hills. The Mountaineers, Seattle, 1997, 528 pp.|
|Glaciers. Michael Hambry & Jurg Alean; Cambridge University Press, 1992, 208 pp.
## General info about glaciers and glaciology, with very nice color photos.
|Glaciers of North America. Sue A. Ferguson; Fulcrum Publishing, 1992, 192 pp.
## General info about glaciers, glaciology, and glacier travel, with a field guide to many acessible glaciers.
Click on any photo to go there, or start your tour with the first photo...
|Starting Elevation:||5400 ft (1650 m)||Weather Conditions:||Clear, light winds|
|Highest Elevation:||7200 ft (2200 m)||Temperature:||30-60 F (0-15 C)|
|Roundtrip Distance:||5 miles (8 km)||Visibility:||Over 100 miles (160 km)|
|Total Vertical Skied:||2700 ft (800 m)||Ski Conditions:||Firm changing to mushy|
This was the field trip for the 1997 Glacier Skiing & Crevasse Rescue Course, one of the many excellent courses offered by the Mountaineers Backcountry Skiing program. Our party of thirteen was led by Dale Rankin.