Mar 20, 2017

The problem with the “modern” avalanche danger scale – don’t underestimate an off-piste day when the bulletin says 3

This is not about different types of avalanches or just the risk of skiing off-pist. This is, hopefully, to make you think of the risk of the avalanche scale and what it accually means.

The Commission for Snow and Avalanche Research was founded in 1931. And as the name says, the main purpose was to do research on avalanches.
In 1936/37 the Swiss Ski Association started to give weekend snow reports over their part of the Alps, at that time via press and radio. (for our younger readers, internet wasn’t invented yet) In 1945 todays SLF Swiss Snee institute, took over the responsibility and established the modern avalanche warning system. Every week the bulletin was reported and the releases were welcomed both by winter sport resorts as well as agencies responsible for public safety.The system was improved with telex comunications with Davos, which became the headquarter and still is. In 1989 the reports also became accessible via phone, #187, which still is in use.

  The avalanche danger scale had and still has two main purposes. One is to express the risk that a catastrophic avalanche will threat public life such as roads and villages. The other more obvious in ”skiers” use is the probability of an avalanche in a ski area. But maybe more interesting, to give an idea of the danger outside the resort. Easy put like in the off-piste terrain.

EAWS, European Avalanche Warning Services

The European Avalanche Warning Services, EAWS, founded a working group in 1983 with the main goal to improve the avalanche system, so it could be used by all the relevant countries, that until then had a number of different scales and levels.
The modern 5 point scale was introduced in 1994, becoming an international scale in the purpose to make it easier to understand. Which maybe was the fact at that time, but is it still? That´s the question!

In my opinion the avalanche danger rating scale is pretty confusing. Avalanche danger rating 3 on a scale of 5 doesn't sound too dangerous. It's right in the middle! So it is easy to think that there isn't much of a risk when going off-piste on a day like that. Something that I often overhear in the cable bin on my way up to the days skiing.
But take a moment to consider this, that while there is different number on the scale, the color on the alert flag is the same for 4 and 3, which indicates a high avalanche risk. One thing that, in my opinion, most people tend to forget about.

With the avalanche danger rating Considerable!! (3) approximately some 20% of the snow cover has weak spots. Spontaneous avalanches of medium size is possible to be triggered, just by it self! The weight of one single skier / snowboarder could be enough to trigger an avalanche. The potential damage danger says it could bury and destroy a car, damage a truck, destroy small buildings and break trees.
So with that in mind, avalanche danger rating Considerable (3) is dangerous!
Just taste the word, considerable.

Rating 4 (High) and 5 (Extreme) for sure express the risk of a avalanche even on the gentles slopes with only light load. Off-piste skiing and snowboarding is not a good idea during those rating levels. Most ski resorts will even be shut down completely during avalanche danger rating 5 (Extreme) and many will close already at 4-High. And some would afterwards wish that they had!
Some lifts might stay open with avalanche danger rating 4 (High), but these will only bring you to low angle slopes with no or not exposed steeper faces above them.

Avalanche danger ratings 1 (Low) and 2 (Moderate) on the other hand are more reasonable for skiers and snowboarders who want to ride off-piste. And then we have the unpredictable and in between 3 that express Considerable.

Basicly, the avalanche danger rating scale for skiers and boarders has been reduced to two rating levels, 2 and 3.
Since 4 and 5 isn´t  a free riding day and 1 feels super safe, right!?

This rating on a single 3 (Considerable) claims 54% of the avalanche victims*
Clearly showing that the rating is dangerous for skiers and snowboarders. In Switzerland most of the accidents occur when the bulletin has 2 to 3. Same for Austria. (,11.39)

The new Swedish system, adds a couple of new features to the origin system. Which hopefully will make the freerider a little bit more attentive.

The basics
On a risk 3 day, the best solution is to stay away from slopes over 30° and stay focused. Consider the terrain also on a day with that simple 3. Ignoring old tracks and other skiers. And instead think about wind and temperature. Remembering that a 3 on the bulletin in the resort doesn’t mean that is a 3 on slopes outside the ski area. That is one reason for example that when you are skiing in la Balme, Chamonix, and heading out east from the top chair lift of tete du Balme, you have to go under a rope! Meaning, you are in uncontrolled area.

So with this in mind, the avalanche danger rating scale can be pretty confusing.
If you don't have the right knowledge or if you don't know that you can make the right decisions in the backcountry, maybe its a good investment to take part in a course or hire a professional Mountain Guide.

If you want to learn more about the risks of skiing and snowboarding in the backcountry and how to manage those risks there is a bunch of alternatives.
For a good bace and knowledge regarding courses contact SBO (Swedish Mountain Guides) or Mountain Academy.
But most important, don't take the 3 to easy! Consider!! as the color and sign says, Considerable, and don't be a figure over victims!

*in Switzerland!

//Krister JonssonIFMGA Mountain Guide

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