In my last post, I remarked on an avalanche described in Backcountry Magazine. As promised, here is some discussion that skips the armchair quarterbacking.
Background
Conditions on the day of their ski tour were as follows: a snowpack with a history deep instability had been very recently loaded by rain that was followed by 18 inches of snow. Obviously, even a cursory evaluation of conditions on the day of the tour should have raised awareness about the presence of instability. That aside, if the potential for high instability wasn't obvious from the recent weather and the history of the snowpack, the results of an extended-column test performed by the skiers ( ECT 5 Q2 ) should have been conclusive.
Yet despite the history of the snowpack, and despite the recent loading, and despite snowpack tests, all of which pointed to widespread instability with low triggering energy, the group ventured toward avalanche terrain and triggered an avalanche large enough to bury, injure, or kill a person. Thankfully, no one was injured.
From reading the article, and from examining their terrain choices, it seems as if the skiers were confused and uncertain about instability. Yet the manner in which I have laid out the facts about conditions leaves absolutely no question about the presence and parameters of snowpack instability on the day of the avalanche. So, as with all forms of armchair quarterbacking, in hindsight the snowpack instability seems perfectly obvious...
Clearly something doesn't add up.
Analysis
Armchair quarterbacking is linked to the old saw: hindsight is 20/20. Therefore, when analysing accidents, it's critically important to ask the right questions: Do we really know if the skiers collected information in the same manner as us? What I mean is, did the skiers systematically collect and integrate information about conditions on the day of the ski tour? The article makes it pretty clear that the skiers collected information, but we do not know if they did so systematically, and despite being 'experienced', they clearly did a very poor job of integrating the information into their forecast. Did the skiers even develop an avalanche forecast? We don't know, but it isn't mentioned in the article.
Unfortunately, 'experienced' backcountry skiers frequently make dangerous mistakes, and the reasons why 'experienced skiers' make serious mistakes is a subject of much discussion in the avalanche research community. The magazine article chalks the errors up to powder fever and human factors, but I think both of these are just red herrings. Uncovering the actual mistake is important if we want answers that are clear and useful. Powder fever is certainly dangerous, but repeating that message doesn't really help anyone when powder fever is not the underlying cause. ( In medicine, fever is a symptom that reflects an underlying condition. ) Careless oversimplification greatly reduces the value of discussing skier-triggered avalanches.
After reading the description of their ski tour and the avalanche, the fundamental mistakes became very clear: the ski tour was a somewhat organic, loose, and chaotic endeavour on a day when avalanche danger was high. The presence of chaos is an extremely important clue, because it reveals what really went wrong. Just think about it for a moment .... a chaotic ski tour ... poor choice of objective ... on a day when avalanche danger was high ...
In this case, hopefully we can agree that 'experienced' refers to a person who has engaged in several seasons of ski touring. Hopefully we can also agree that there is a relationship between skill and experience, but that being experienced is not the same as being skilled.
What would lead a party of 'experienced' backcountry skiers down the garden path?
Lack Of Planning: A Fundamental Error
At the beginning of this post I stated that snowpack instability was glaringly obvious when in hindsight we systematically collected and integrated information. Armchair quarterbacking is so easy precisely because it's very simple to systematically collect and integrate information after the fact. But if you're a backcountry skier, it's incredibly important to systematically collect and integrate information before, during, and after a ski tour.
Of course, the systematic collection and integration of information has important implications, doesn't it? And what might those be? Is it possible that the systematic collection and integration of information occurs only when a ski tour is properly planned and properly executed? What are the odds of properly executing a ski tour when the trip has been poorly planned? The article content makes it quite clear that the ski tour was chaotic. So, even if there was some degree of planning, the planning certainly wasn't done properly. Second, the ski tour was executed in a rather haphazard fashion.
We know that a variety of activities such as map reading, instability tests, and route-finding took place on the day of the ski tour. That these activities had taken place obviously lead the participants to believe that their ski tour was properly planned. Yet none of the skiers discuss a formal trip plan, and this leads me to conclude that their tour was not properly planned, but merely discussed instead. Poor planning allowed 'powder fever' and 'poor communication' to take control of the situation. It's very simple: if you don't take control of the situation, something will, and this is doubly true for situations where uncertainty is high. ( I've written about the effects of unmanaged uncertainty. )
The article describes the skiers as experienced. Yes, there's that ugly word again. Since when did experience serve as a substitute for proper planning and execution? Please allow me be perfectly clear: discussions are not planning and experience does not guarantee clean execution. Rather than chalking up another series of mistakes to 'powder fever', it is more useful to consider how and why the circumstances developed in the first place.
Planning is a reality check that you can't afford to miss. If you don't plan, you're being intrinsically careless. If you don't plan properly, you're not planning. If you plan and execute poorly, you fail. Most of the time, failing to plan and poor execution won't have any consequences.
Most of the time.
Conclusion
Failing to plan is a serious primary error that creates situations in which secondary errors will occur. Rather than focusing on becoming an experienced backcountry skier, choose to become a skilled backcountry skier instead.
A Formula For Winter 2010-2010:
Solve for PYST, where = P = Plan, Y = Your, S = Ski, T = Tours
Planning Tips
Here are some planning resources:
- Google Maps ( Select More » Terrain for online contour maps. )
- Backcountry Skiing: Skills For Ski Touring & Ski Mountaineering
- Washington Terrain Ratings ( From This Blog )
- Elements of Backcountry Avalanche Forecasting ( From This Blog )
Here is a planning checklist:
- What is the current danger level?
- Who is going?
- What are their phone numbers?
- What is their contact info?
- Is our objective appropriate for the current danger level?
- Do we have powder fever?
- Have I planned the trip?
- Do I have a map?
- Have I analysed the terrain beforehand?
- Do I have a list of safe alternates?
- Have I separated the trip into legs with times, distances, and elevations?
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