This months TAR (The avalanche review) from the American Avalanche Association has some of the most insightful articles on avalanche education and psychology that I have ever read, as well as a review of what works and what doesn't in avalanche forecasting. Folk are trying to grapple with another season of serious incidents on both sides of the pond, and understand why the majority of these occur in days of medium risk, "considerable" or the old Scottish cat 3 for example. Understanding why is not rocket science when you get to the basics. The key word is uncertainty. Forecasting and risk assessment is about predicting and therefore will always be uncertain and a game of probability. Here's my take on what I have been studying/reading.
The top graphic is pretty obvious. There is a certainty that natural and human triggered avalanches will occur above 900m on NW to NE aspects and localized risk below this altitude from West through North to East. Most folk with a brain will avoid the areas above 900m as RED is the colour of danger (obvious!) and will choose to go to safer aspects which in the above is green which as a colour gives the assurance of greater certainty. Things become more uncertain on yellow and especially orange. This uncertainty is where the risks are, and things become even more uncertain when the risks are localized. Yellow the probability of getting caught is less probable but still very uncertain, stick a localized considerable orange pizza in there and you have a mine field of uncertainty lying in wait. You can't see the mines but can guess using the wind direction and slope shape as as to where hot spots of weakness might be (a guess - all be it an intuitive one) but you have to be very uncertain as you just don't know.
How do you mange or minimise risk if you have to travel on these aspects or choose to ski them? Well you don't manage the risk with any degree of certainty as you just don't know for sure where weak spots are, and you will for sure not know the true propagation risk from a trigger. You can't minimise what you don't know - so uncertainty! And yet graphically on the above for the inexperienced person there is a temptation to look at these localized hot spots in the rose and think "I can avoid them", as surely I will recognize these weak areas and can ski/walk/climb around them. This is in fact what seems to have happened in a recent tragic ski avalanche.
So my take on why it is that most folk get whacked when the risk is considerable or localized considerable is that being outdoor optimists (as we all are), and perhaps having got knackered climbing up a mountain or skinning in to a valley, or maybe having a bluebird pow day is folk just get used to that risk level as it's used the most, and yet has the most uncertainty and therefore is the most dangerous level of avalanche prediction for the winter sports person. Make sense?
I suppose if you were to roughly put a % chance of probability on the European avalanche scale you could say that:
Black 100% chance of getting whacked while either minding your own business in
Galtur or being suicidal in Tignes
Red 98% chance of getting whacked on an aspect with that risk
Orange is a big problem (to me) be it slices of cake sized considerable or inserted mini pizza. If the rose is all orange then in my view its just the same as red. You have a very high chance of getting whacked. Stick some little orange pizzas on yellow then it becomes 50/50 and that's still scary uncertainty as folk think they can recognize the danger hot spots and avoid them. It's a minefield!
Yellow maybe a 40% of getting away with it, but victim triggered death is still very likely if you hit an orange hot spot.
Green well either its the best of Scottish neve with blue skies, or get the lawn mower out in February. If its the best of Scottish neve then watch out as next time it snows as there's bound to be something growing on the top surface.
Having a blue bird day, or up for it then the glass half full person will go for it. Sadly they might end up with the glass all empty and smashed. It's a bit of a gamble and the more times you roll the dice the more chance you won't be needing your old age pension. 50/50 isn't odds, its worse than Russian Roulette!
