Avalanche: Keep Yourself Alive Out There
HOOSIER PASS
It’s a powder day high on the Continental Divide. Three inches of snow have coated the evergreens like a winter postcard and left the ground pillowy and untracked.Tromping in snowshoes toward timberline, above the 11,452-foot pass that separates Summit and Park counties, it’s hard to imagine that this gift from nature could mask a hidden danger.
But the picturesque blanket of snow hides layers underneath — solid icy slabs, soft filling, another slab, and beneath it all, the sugary few inches known as “depth hoar.” It doesn’t take much pressure with a shovel to make the layers slide apart.
That’s why we’re here. Avalanche danger is a concern throughout winter and spring in Colorado, usually because our storms tend to be broken up by days of the sunny, bluebird skies that draw many of us to the high country.
Colorado leads the nation in avalanche deaths, with 241 between 1950 and 2011.
But it’s no reason to avoid the backcountry. In that spirit, I took an Introduction to Avalanche Safety class with the Pikes Peak Group of the Colorado Mountain Club.
With the right training and gear, outdoors lovers can penetrate the depths of Colorado’s high-country wilderness with confidence.
KNOW WHAT TO LOOK - AND LISTEN - FOR
Survivors typically describe a cracking sound.A slab of snow breaks away from the mountainside, and anyone unfortunate enough to be caught in it is hurtled down.
About a quarter of people who die in avalanches are killed by the impact of the snow, or by hitting rocks or trees. Those who survive the slide often find themselves buried. Unable to move, their breath forms an icy mask and they asphyxiate, usually within 15 minutes.
During two nights in a classroom and a day on Hoosier Pass, much of my avalanche safety class was focused on not getting into this position.
Any backcountry snowshoe, snowmobile, cross-country skiing, alpine skiing or snowboarding trip to the mountains should start with a visit to avalanche.state.co.us, the CAIC’s website. Forecasters rate the danger for every mountain range on a scale of “low” to “extreme.” If it’s “high” or “extreme,” usually right after a heavy snowfall, consider staying home or choosing a route far from any steep slope.
Most deaths occur when the rating is “considerable,”
as it was during our field trip. It’s a gray area, and unless your trip takes you across flat terrain or to valleys far from any suspect slope, the best thing to do is dig deeper. About four feet deep.Dig a pit in the snow near where you will be playing, on a similarly-angled slope, and examine a flat cross-section of the snow. With gentle finger pressure you can identify the different layers of snow. Dig out a column and see if levels collapse when pressure is applied on the top and then again, when digging behind it with a shovel.
Ideally, you’ll find consistent snow without layers. For us, it was easy to make the upper hard slab come off. And it was easy to imagine how much damage 100 tons of that slab rolling downhill could do.
Most avalanches occur on slopes with grades of 30 to 45 degrees.
The one we were on was about 20 degrees, and most in our group agreed we would not ski anything much steeper in these conditions. With such unstable snow, we also agreed we would confine our hiking to ridgelines, which are generally safe.But simply staying away from steeper slopes is not always enough. “All snow is connected,” said our instructor, and when a slab of snow is under enough pressure, stepping or skiing even on the lower aspects, the area called the “run out,” can lead to a fatal slide.
HAVE A PLAN IN HAND
Most of the time, you’re not in danger of an avalanche unless you put yourself in harm’s way.Experts cite a number of human mistakes in most avalanche deaths: people believe terrain is safe because it’s familiar; they dismiss risks because of “summit fever” or “powder fever” or because they’ve spent a lot of time and money on a trip; they bow to the actions of the group’s “expert”; they believe tracks made by others mean a slope is safe; they don’t voice concerns because the rest of the group seems fine with the conditions.
If you’re heading into the backcountry, you must be able to rely on your companions. After a slide, getting timely help is rarely an option.
“It’s the people who are there who are going to pull out a live victim. If you get a team together, it’s a body recovery,” said course instructor Eric Hunter, of Colorado Springs.
Everyone going into avalanche-prone terrain should wear an avalanche beacon,
a device that emits a signal that other beacons can latch onto to locate someone under the snow. During the field trip to Hoosier Pass, everyone in class spent a couple hours practicing finding beacons buried in the snow. They’re not cheap — a new beacon can cost $250 — but they’re essential gear, along with a shovel and probe for finding a victim under the snow.Some extreme backcountry skiers also wear Avalungs, which allow you to exhale carbon dioxide into a tube to preserve your air pocket if you’re buried. And some wear airbags that can help you float above the snow during a slide.
My avalanche awareness class focused on removing the fear of avalanches and creating confidence to step off the beaten path. It’s the most basic avalanche training. Other classes require many days of field and classroom and book work.
“If I’m going to get out in the backcountry, I kind of want to stay alive,” said Shari Pederson, of Colorado Springs. “Understanding will take some of the fear out and allow me to get out there and off the couch.”
WARNING SIGNS
• Danger rating from the Colorado Avalanche Information Center• Heavy recent snow, 1 inch per hour or 12 inches in a day
• A weak base layer of snow and a consolidated slab
• Rain on the snowpack
• Regular melting and refreezing
• Wind-blown cornice above the slope
• A “whoomping” sound of air escaping below you
• Recent avalanche activity
• Trees are “flagged,” showing where a slide has knocked them over or stripped off all vegetation on the uphill side
ESSENTIAL GEAR
• Avalanche beacon for everyone in a group, with fully charged batteries• Collapsible probe to look for victims under the snow
• Shovel
• Slope meter
• Helmet
IF YOU ARE CAUGHT IN AN AVALANCHE
• Yell to your partners• Throw away ski poles
• Fight to stay on top, swimming and flailing with arms and legs
• If possible, grab a rock or tree
• Close your mouth
• As it slows, throw an arm upward and take a deep breath
• Make breathing space by putting an elbow or hand in front of your face. Don’t struggle or breathe hard.
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