Avalanche warnings from this week and last week prompt recreators to proceed with caution while in the backcountry this spring.
The Copper River Highway avalanche hazard was listed as low on Monday, but may increase mid-week. The backcountry avalanche hazard was considerable above the tree line and moderate at the tree line. Backcountry and avalanche forecasts are sponsored by The Alaska Avalanche Information Center (AAIC).
AAIC warned that backcountry skiers and riders should exercise caution around wind loaded western aspects. Last week’s precipitation and strong winds contributed to avalanche activity in the area. But dry, mild weather since then has created some snow stability.
“Avalanches occur more than most people realize, but avalanches are only a problem if they affect people or property,” said AAIC president Steve “Hoots” Witsoe. “Avalanche hazard is defined as probability of an avalanche occurring multiplied by the consequence if it did happen. The risk is defined as the hazard multiplied by exposure time. The best sign of avalanche hazard is recent avalanche activity, emphasizing recent.”
Monday’s warning was tamer than the warnings on March 14 and March 17, which listed avalanche danger as moderate to high.
Witsoe said that conditions of avalanche activity relate to rapid increase of stress on the snowpack (such as precipitation, wind, and users), or rapid decrease of strength of the snowpack (such as warm temperatures, rain, or strong sunshine).
An avalanche is a mass of snow moving down a slope, and can cause injury or even death. Avalanches are most common from December to April. Avalanche risk can be mitigated if people wait for snow conditions to stabilize after snowstorms, and avoid avalanche chutes.
“The avalanche season around here usually begins by December and can last through May,” Witsoe said. “In the beginning of winter, the snowpack tends to be shallower, so avalanches tend to be smaller and don’t travel as far. As the snowpack gets deeper, features are filled in allowing avalanches to be larger and travel farther. In the spring, increasing temperature and sunshine decrease the strength of the snowpack, causing what we call ‘spring shed.’”
Before heading out into avalanche danger zones, adventurers of all skill levels should: have a plan based on the most current avalanche and weather forecasts, ensure everyone in their group has the appropriate gear — including shovel, probe, and transceiver — and knows how to use them, and avoid recent avalanche activity areas; and take an avalanche course.
Witsoe advised that recreators stay above potential avalanche areas, know the hazards around them, and know potential escape routes. If recreators must cross an avalanche slope, go one at a time and keep an eye on members of your group, he said.
If someone gets caught in an avalanche, “try to quickly get out of the moving snow, whether to the side or holding your position and letting the snow move past,” he said. “If you can’t get out, try to stay on top of the moving snow, protect your head, and try to make on air pocket as the snow comes to a stop.”
AAIC was founded in 2008 and earned nonprofit status in 2010. It sponsors four independent avalanche forecast centers in Cordova, Haines, Valdez, and the Eastern Alaska Range.
AAIC standards follow guidelines established by the American Avalanche Association, the National Avalanche Center, and the American Institute for Avalanche Research and Education.
Further avalanche information for the region and around Alaska can be found online at http://www.alaskasnow.org.
