Terrain Tips Intro: When Unstable Snow Is the Problem, Terrain Is the Solution

Terrain Tips Intro: When Unstable Snow Is the Problem, Terrain Is the Solution

I received an email today from a colleague in Utah: “The snow continues to fall in most places and avalanches are still happening. Forty-three human triggered slides in five days here in the Wasatch, with 14 people carried, several of whom were in singular avalanches. People took up to 2000-foot rides and not so much as a scratch. Miraculous?”


In January, the CAIC reported 129 human-triggered avalanches. In February, they reported 122 human-triggered avalanches. Hmmm… I wonder how many more occurred that were not observed or reported? Half again as many? Double is more likely.

This is a high number of human-triggered backcountry avalanches and scary near misses, even in light of the increasing number of backcountry recreationists out there each week. As a guide and avalanche educator, this worries me. I think I know the risk, and my experience tells me that even small avalanches can be dangerous, even deadly.

My head swirls with questions around these incidents. Do people not understand the avalanche risk? Did they read the avalanche forecast? Did they not get it? Was the advisory’s message simply not clear? Did these people have a strategy to reduce the risk? Or did they just leave the house, go where they wanted to go, and roll the dice with a significant chance of harm?

The avalanche risk can be defined with a pretty straightforward formula:

Likelihood of an Avalanche Involvement


The Consequence if Caught

 = Chance of Harm

Winter backcountry enthusiasts need a workable strategy to reduce their risk. It is every person’s task to reduce the chance of encountering an avalanche and to do everything he or she can to reduce the potential consequence. 

In an avalanche course, you learn ways to reduce the potential for harm. This includes wearing a transceiver that helps you search for someone who has fallen into a tree well or buried in an avalanche and wearing an avalanche airbag that may reduce the likelihood of an avalanche burial. You are also taught to post trained spotters to observe and stand by with search and rescue equipment (probe, shovel, and communication device). You are told to secure your jacket, tighten pack straps, and remove your pole straps before entering a potential avalanche slope. These essential tools, while reducing your vulnerability, do nothing to reduce the power of an avalanche, and therefore do not adequately reduce the chance of harm.

And we can’t forget that subconscious influencer: bias. It is certain that traipsing around in familiar terrain, with a couple of fit and psyched pals, each one equipped with avalanche gear and rescue training, makes us feel safer and overconfident in our terrain choices.

The bottom line is you don’t want to get caught. Ever. Popular freeride videos often depict pro skiers triggering shallow loose-snow or small-slab avalanches in steep terrain and skiing out of them. This is a “don’t try this at home” scenario. Most of us, at least in North America and Japan, spend much of the winter in steep, sheltered, partly forested terrain where small avalanches can have big consequences if we are caught, buried, or pushed into a tree. If you doubt the impact force of small avalanches, consider that a small slab avalanche moves downslope at least 30 kilometers per hour. Larger avalanches or smaller avalanches on a longer slope move much quicker with more destructive force—over 100 kilometers per hour if a big slope runs full path. 

Picture yourself in the back of an open pickup truck, jumping out and hugging a telephone pole at 30 kilometers per hour (20 miles per hour). You don’t need a science degree to calculate how much that would hurt. Getting pushed into rocks or trees by a small avalanche may result in injury or death.

And even if you don’t hit anything but are buried in a tree well, creek, or terrain trap, it may end badly. The survival chances for a completely buried person dwindles dramatically after 12 minutes. If your freeriding buddy punched it 100 meters downslope before posting up onto a safe spot, it could easily take him more time than you have to get to you, pull out the probe and shovel, dig you out of a complete burial, and be the hero who saves the day.

It is obvious that the good decision-making includes using terrain to reduce the risk. There is a well-worn ski guide’s adage that states:

When unstable snow is the problem, terrain is the solution.

Our best approach heeds that adage:

  1. Avoid terrain that has a chance of avalanching.
  2. Choose terrain that may reduce the consequence if you are caught.
  3. Choose terrain where, if nearby terrain does avalanche, you won’t get caught.

That formula sounds easy to apply. But what does it actually look like to use terrain in a way that reduces your risk? Read Terrain Tips, Powder Cloud‘s new avalanche education series, to learn how.

Colin Zacharias is a consultant and educator in the avalanche and mountain guiding industries, and an IFMGA/ACMG mountain guide. He resides on Vancouver Island.

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