What happens in an avalanche:
1. A solid portion or slab of snow breaks off and begins sliding down hill.
2. The slab or soft, wet snow begins to brak u p into chunks.
3. The violent tumble downhill smashes the large chunks of snow into finer pieces.
Source: The World Book, The Avalanche Book
Most avalanche fatalities by state:
Colorado
Washington
Alaska
California
Idaho
Utah
Montana
Nevada
Wyoming
Oregon
Worst months for avalanche fatalities:
January
March
February
December
The real voyage of discovery consists not in seeking new landscapes, but in having new eyes.
Marcel Proust
Winter’s fallout
Heading for the back country? Don’t mess with avalanches
What do skiers, snowboarders and avalanches have in common?
They all like fresh snow.
That’s not meant to be a joke – the truth in the statement carries too many deadly realities.
It is this very fact, though, that is contributing to a grimly steady increase in the number of avalanche-related deaths each year.
Photo by Richard Armstrong,
National Snow and Ice Data Center
The wake-up call arrived when Arizona, a state not normally associated with snow sports, recorded its first avalanche fatality. Snowboarder Richard Nurczynski suffered massive injuries after being swept 400 feet down Agassiz Peak beyond the boundaries of Arizona Snowbowl ski area outside Flagstaff.
If statistics hold true, it won’t be the last, given the trend toward “extreme” skiing and snowboarding, which involves venturing into unmonitored and uncontrolled “back-country” mountain areas.
Snowbowl manager J.R. Murray said those who venture beyond ski-area boundaries are crazy. They might well be if they do so without a rudimentary understanding of the potential threat posed by unstable snow, because they’re risking life and limb.
Unfortunately, more than offsetting the threat these days is the lure of fresh, untracked snow for adventurous skiers and snowboarders. They join an assortment of other winter athletes and workers who comprise a high-risk group that is most likely to cross paths with avalanches.
Statistics provide the details. In their comprehensive work, The Avalanche Book, Betsy Armstrong and Knox Williams not that avalanche deaths quadrupled during the 35-year period since 1950, during which most Western snow sports areas began operations. Average U.S. fatalities per year increased from four in the early 1950s to more than 16 in the mid-‘80s.
Mountain climbers understandably have been the highest risk group, losing 84 members during the same 35-year period. Next was ski tourers (usually Nordic or cross-country skiers but increasingly “extreme” alpine skiers) with 69 deaths. Lift skiers (also called alpine or downhill skiers) were third with 42 deaths.
Since that study period, the trends have continued as more people venture into wintry wildernesses. Colorado had a record 12 fatalities a few winters ago. It has many of the country’s famous back-country ski and snowboard areas and is by far the leading state for avalanche deaths.
Ski resorts do a good job of policing their high-traffic recreation areas. Ski patrols constantly monitor conditions and use a variety of methods to defuse potentially dangerous situations.
Scott Clements, head of the patrol at Sunrise Park Resort in eastern Arizona, said his crews most often find hazardous conditions building on the resort’s steepest runs early in the season after heavy snow accumulations and windy conditions that cause drifting.
Remedies include stabilizing the snow by packing it down with skis or safely causing it to dislodge with 2-pound dynamite charges. Larger ski areas even will use artillery to cause controlled slides in inaccessible areas.
Beyond ski areas, the reasons for and types of avalanches are as varied as the weather that causes them and the terrain involved, but certain factors are generally true, according to The Avalanche Book:
They usually occur:
- Early or late in the winter when temperature fluctuations cause layering of dissimilar types of snow that increases chances of shearing.
- During or soon after winter storms, especially when winds are strong.
- On terrain above timberline and steeper than a 30-degree incline.
- On northeast slopes where prevailing southwest winds deposit snow.
But don't rely on prevailing trends; the deadly avalanche on Agassiz Peak was atypical in that it happened on the south side of Fremont Saddle after unusual northern winds.
Those who must venture into areas matching those conditions are advised to stay above unstable snow terrain or well below it. Above means windward side of ridges. Below means stay clear of or certainly don’t linger in runouts, which often resemble the white vertical swaths of ski runs because previous avalanches have cleared out any timber or other ground cover.
The Colorado Avalanche Information Center in Denver advises those who find themselves in such threatening environments to do the following:
- Ski out the same way they entered or, if that is not possible, stay near the end or flanks of narrow valleys and away from the middle or lower reaches. Monitor terrain, the center advises, and stay away from cliffs, tree stands and gullies, where room to maneuver in an emergency is most limited.
- Carry a shovel and collapsible snow probe (available at mountaineering shops) if venturing into suspect areas. Avalanche warning beacons, which help locate buried winter athletes, are useful only if users are familiar with their operations.
- Suspect areas should be crossed one at a time by party members so others can warn of impending danger and assist if a rescue becomes necessary.
Although options are limited should one get caught in a slide, The Avalanche Book suggests trying to escape to the side or grabbing a fixed object if that is not possible. Nurczynski’s snowboarding companion escaped injury by clinging to a tree.
The Avalanche Book advises anyone buried in snow to first remain calm because less oxygen is consumed, assess whether any body parts can be moved and, if so, begin attempting to move toward the surface or create and vent hole for breathing.
“The average depth that people are buried in snow is 1 meter (3 feet),” Clements said, explaining that escape becomes the next priority.
Clements said rescuer by fellow party members is the best chance or survivl. Ski patrol members who take avalanche hazard reduction classes learn that it is essential to find anyone buried in snow within three minutes, because oxygen deprivation usually begins causing irreparable brain damage after that.
An avalanche can result when wind conditions, earthquakes, or explosions destabilize a large buildup of snow on a mountain ride. An avalanche also can occur when skiers travel over unstable snow ridges.
Copyright Gary Olson 2010 First published in The Arizona Republic
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