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How I Came to Know and Love the Backcountry
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Avalanche awareness is a science, and nothing that can be written here will ever substitute for the lessons learned while taking a course in avalanche rescue and safety, and practicing it diligently. The point of this section is to clue you in on the need to study further. Ask any avalanche veteran and they’ll tell you that even years of study and experience fail to explain unpredictable snow behavior. All you can do is improve your chances. In a nutshell, this is how it works:
Snow accumulates in layers. Just like rings of a tree trunk, a snow bank records the season's storms, and bonds to itself. Horizontal layers will be stable if the snowpack and temperatures are consistent, and unstable if they vary widely (i.e., a warm icy storm followed by a large cold dump). Like a viscous liquid that hasn't started moving, snow is pulled downhill by gravity but hangs in place by the force of its bond to the snow around it. The more snow that exists on a steep slope, and the slipperier the surface it sits on top of, the more tension builds between it and the surrounding snow. Eventually, the subtlest of shifts (like a skier's turn) will release that tension and a massive layer of snow will break away from its bonds and start flowing downhill. Voilà, an avalanche. It is not uncommon for a layer six feet thick and several football fields wide to slip away in one instant, careening downhill at up to 100 miles per hour.
The general rule of thumb? The place that looks most enticing to ski is also probably the most dangerous. Most avalanches occur on slopes between 30 and 45 degrees, on leeward, open areas. Most avalanches are triggered by the people who get caught in them, and can be set off from far below, as well as in the middle of a slope. Thirty people died in avalanches in the United States last year, a normal rate. Second to snowmobilers, backcountry skiers are the most likely victims. Anyone buried in an avalanche has about 25 minutes before they suffocate to death. If you find yourself in such a position, don’t go for help; you’re it. Start digging.
Avalanche safety begins with understanding avalanche dynamics as well as the history of the region's climate throughout the season and its current conditions. Backcountry travelers wear transceivers, which emit a small radio signal if you are buried, and can switch to receive a signal if you need to search for someone else. This tool is essential for rescue, but only worth the strap it hangs on unless you know how to use it. It takes practice, and instruction. The secondary tools are shovels (not just for digging out, but for digging pits to analyze the snowpack before you ski), and a long metal probe pole for the ugly task of poking avalanche rubble for bodies.
There are standard practices that will help you avoid getting into a rescue situation in the first place. First, be humble and avoid bad conditions. If the avalanche center reports a high risk, stay home. If your gut says stay home, stay home. If you ski ten miles into a perfect bowl on a sunny day only to find something doesn't look right, turn around. Live to ski another day. When you're up on the slope getting ready to descend, dig a pit with your shovel. This allows you to see the different layers of the snow you'll be skiing on, and will tell you how easily the slope will slide. Do this at the start of every run, as conditions can change based on hourly weather shifts, or within a couple hundred feet on the same slope. Stay away from slopes that have accumulated bulbous drifts due to wind deposit rather than natural snowfall. There are much more advanced techniques for this—take a certified class, do your homework, and read further.
Still not convinced that avalanches are layered with complexity? Read Outside's "Anatomy of a Slide"—and enroll in an avalanche safety school.
Details mentioned in this article were accurate at the time of publication