Avalanche safety can seem like an overwhelming subject. There’s lots of nerdy science and meteorology that hangs around it, and the outcomes of getting it wrong can be very serious – life threatening, in fact.
I’ve experienced this myself. When I first did my avalanche awareness course, I suddenly became paranoid whenever I ventured into the backcountry, a completely normal and recognised phenomenon that is all part of the psychological process of coming to understand avalanche safety.
Sometimes it takes a different approach or reading about things in a slightly different way to cut through the noise and remind you of the fundamentals. I’m a big believer in simplifying avalanche safety at every turn; the biggest takeaway I’ve had from listening to The Avalanche Hour podcast and reading The Avalanche Review (the journal of the American Avalanche Association) is that simplicity is key to any messaging you do. You can have the most detailed, most accurate forecast or snowpack assessment, but if you can’t communicate that to the people travelling over the snow, then it is utterly useless.
As part of this cutting through the crap, I take you back to the beginning of any avalanche journey; by recognising and remembering what these key figures mean, it can, hopefully, help ground you in your avalanche safety journey. So here are three key numbers to help you understand avalanche safety.
There’s quite a few terms in here that might be new and unfamiliar to you. Don’t forget to check out Skiing Unlocked’s Glossary of Skiing Terms for a full rundown of definitions and meanings.
95
This is the really big headline number. 95% of all avalanche victims are caught by avalanches triggered either themselves, or by other human activity.
Why is this so important to understand? Well, “conventional” wisdom is that avalanches are random events, caused by heavy snow or just sheer blind luck. But this number cuts through that entirely. Dangerous avalanches are overwhelmingly triggered by people.
That should completely change your approach to skiing off piste. Armed with this knowledge, you can take appropriate steps to mitigate your impact on the snow, reducing the risk to you and your fellow skiers.
4
How do you mitigate this risk? You need to consider the 4 Factors that you can control or understand to make better decisions in the backcountry. These are terrain; snow; weather; and the somewhat miscellany human factors.
Terrain is the easy one; stay away from avalanche risk terrain, or, if you have to travel through it, take measures to mitigate your risk. Avalanches only occur on slopes of between 30 and 40 degrees inclination; stay away from these slopes when the risk is elevated.
At the same time, be wary of travelling through terrain where snow above you can avalanche down on to you – this is one definition of a “terrain trap”. How can this snow fall down onto you? Perhaps it’s a cornice, a windswept feature of snow overhanging a slope that can break away and trigger an avalanche.
And if you can’t avoid avalanche risk terrain? Take appropriate measures. Travel one-by-one across the terrain in question, so that if the worst does happen there are extra bodies to effect a rescue. Draw a firm line in the sand about travelling across terrain where there exacerbating factors in the path of an avalanche, such as rocks or cliffs – the other definition of a “terrain trap”.
What about snow and weather? These can be confusing as they do similar things, but snow is the snow that has been and has formed the snowpack over the entire season to date, and weather is the snow, rain and wind that has happened in the last few days.
Is the snowpack – the total accumulation of snow so far this season – stable? Then you can ski riskier terrain more confident that it will hold and not slide. How risky is entirely up to you. What has the weather done in recent days? Has it been windy, potentially moving snow and loading cornices or increasing the load on risky slopes? Has the temperature changed, increasing to melt layers of snow, the resultant water destabilising the snowpack? These all seem like a lot, but will be broken down really clearly and effectively by local avalanche forecasts in your area.
Finally, the human factors. These are a series of woolly things that are all about how we as individuals make decisions. Are we at risk of blindly following someone we consider an expert? Are we subject to peer pressure to make us ski terrain we don’t feel comfortable doing? Is our communication, our aims and our planning good enough to avoid or mitigate avalanche risks?
These four factors might seem like a lot, but broken down into their components they are easier to understand. They are also the most critical part of avalanche safety.
20
There’s a very funny if very dark Blackadder joke about the “Twenty Minuters” – the gang joins the Royal Flying Corps, a supposedly cushy post where they believe the average training time is twenty minutes, hence their nickname. They couldn’t be more wrong, as it turns out that “twenty minutes” refers to the average life expectancy for new pilots.
Well, this number is a lot more prescient than a throwaway joke from a forty-year old comedy. The “survivability curve” – that is the chance of survival over a period of time – drops dramatically after … you guessed it, 20 minutes.
That means that, if your friend is caught in an avalanche and buried, you must be in a position to effect a rescue quickly. Really quickly.
This isn’t just about being able to dig someone out quickly; you have to find them first. You need to have practice using a transceiver to hunt down other transceivers, and become familiar with the foibles of these devices – did you know that they only pick up a signal within about 40m, or that they will send you in a spiral towards the target as a result of the curved nature of radio wave emissions?
You need to be a good skier, as you’ll be traversing difficult, debris strewn terrain, and possibly hiking back uphill to effect a rescue.
And you need to be able to piece your avi gear together quickly and effectively. A really good practice game is to start with all of your avi gear in your backpack, with it on and strapped in. Hold your breath, and attempt to take out and piece together your avi gear before taking another breath – it’s more difficult than you think, but really good training to help you rescue a buddy in distress.
If it takes a dark sitcom joke to help you remember the importance of urgency, then so be it.
Final Thoughts
So there we are. Three key numbers to help you break down avalanche safety. Some are more complex than others, with some asking more questions than they perhaps answer. But as a gateway to helping you understand avalanche safety and remain safe in the backcountry, there is no better way to simplify and attack from a different angle.
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