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gb
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gb
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PostMon Jan 09, 2017 6:47 am 
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I'll start a new thread because I think avalanche training, knowledge, and human factors should be separated from the threads about recent avalanche victims.

My own experience has suggested to me that when training/experience breaks down is when the snowpack may act unpredictably. Some part of my recognition of this comes from avalanche education. When I look back on my own involvement and close calls regarding avalanches, persistent weak layers have always been present. With persistent weak layers the snowpack will act unpredictably, limiting the value of the application of skills.

In fact most avalanche accidents involving those with more experience take place when the aforementioned conditions exist. And it is here where avalanche training and even experience can break down.

Here is a good paper that categorizes the situations in which French Mountain Guides were involved in avalanche accidents.

http://arc.lib.montana.edu/snow-science/item.php?id=520

ISSW papers are available online to research more about this subject and others.
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nordique
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PostMon Jan 09, 2017 4:33 pm 
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Thanks, Gary.  We seem to be off to a sad start to the avalanche-fatality season.  Even casual hikers need to check avalanche conditions:

http://www.nwac.us/mountain-weather-forecast/current/
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trestle
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PostMon Jan 09, 2017 5:16 pm 
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Certain snowpacks always have persistently weak layers.

Great link by the way.

Interesting, this parallels how many pro patrols are training their staff these days. But then again this information was first shared at ISSW in 2002 so of course it has spread.

Quote:
This approach has lead us to completely change the avalanche course. The section devoted to the evolution and study of snow crystals and the snow-pack has been reduced, while the part devoted to the explanation of the avalanche triggering mechanism and to the study of real cases has been increased.

On a similar note, there was a pretty good article in the Bozeman Chronicle over the weekend.
Human Factor Key in Avalanche Fatalities

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cartman
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PostTue Jan 10, 2017 5:17 pm 
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I'll continue the discussion from this thread here.


Malachai Constant wrote:
"all the experts are dead".

A common and irritatingly persistent myth.

In Staying Alive in Avalanche Terrain 2nd Ed. 2008, Bruce Tremper states (p. 17): "In the U.S. skilled avalanche professionals enjoy a very low avalanche fatality rate compared to other groups, especially when you consider the amount of time an avalanche professional spends in avalanche terrain.  Only 1.5 percent of all avalanche fatalities involve avalanche professionals."

Perhaps the statistics are different in Europe, but I doubt it.  If that were true, there would be a fundamental flaw in European compared to North American avalanche training, assessment and application, which almost certainly would have been fixed long ago.

The two people most highly trained in avalanche assessment I personally know are alive and well.


RumiDude wrote:
But there is also the article which you linked in this that indicates higher levels of avalanche training and experience do not translate into better decision making and less accidents.

Rumi, re: your first point about the Heuristic Traps article and the reference to avy training not seeming to make much difference, that is somewhat supported by Tremper:  "I'm not sure what it is about avalanches, but people invariably overestimate their skills."  However, the article also shows that of the groups caught in avalanches, only 15% were those with advanced avalanche training, easily the lowest number of the four experience categories (Table 2).  So advanced training does seem to correlate with decreased exposure of the group to avalanche accidents.  (Not a bell curve, so I was incorrect about that.)


Per your third point, McCammon also states: "Formal avalanche training did not appear to equip these victims with effective tools for decision making."  Perhaps, and perhaps not.  It seems that heuristic traps tend to override training when it comes time to apply the skills.  After all, it's much easier to make a quick "assessment" of the conditions and give in to the heuristic cues than it is to take the time to make a considered assessment; especially when the cues point to going ahead which is what most people wanted to do anyway--after all, they're out there to have fun.  The Tunnel Creek accident cited by Steve illustrates this very well.

McCammon further states:  "Heuristic traps are attractive because they are fast and convenient for novices".  This should actually read "Heuristic traps are attractive because they are fast and convenient for everyone".  So is it the training that is at fault?  After all, even the best tool is less useful if not used properly.  The problem seems to be one of perspective--the teacher conveying the information and the methods to the student in just the right way--as well as discipline, applying the avalanche assessment tools consistently and effectively every time; in other words, to best teach how to use these tools to override heuristic cues and basic human nature.
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cartman
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PostTue Jan 10, 2017 6:27 pm 
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gb, maybe I'm not clear on where you're coming from...

gb wrote:
My own experience has suggested to me that when training/experience breaks down is when the snowpack may act unpredictably.

gb wrote:
In fact most avalanche accidents involving those with more experience take place when the aforementioned conditions exist.

The article on heuristic traps does not seem to support your hypothesis in most cases.  It seems that people with more experience will still fall victim to heuristic traps in many cases; in addition, due to risk homeostasis they will increase their level of applied risk commensurate with their level of avalanche education, at least to a point, as explained in another interesting McCammon article here.


gb wrote:
When I look back on my own involvement and close calls regarding avalanches, persistent weak layers have always been present. With persistent weak layers the snowpack will act unpredictably, limiting the value of the application of skills.

Yet is this not predictable?  That persistent weak layers are always present whenever you've had a close call?  Unless the persistent weak layer was not detectable--too deep, perhaps--or not expected given the conditions?  An unpredictable snowpack would lead to a breakdown in the expected outcome if it is not detectable by routine methods.
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DIYSteve
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PostTue Jan 10, 2017 7:43 pm 
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cartman wrote:
Only 1.5 percent of all avalanche fatalities involve avalanche professionals."

What percentage of winter mountain travelers qualify as "avalanche professionals?" I don't have any hard data but based on my 40 years of ski touring, I'd guess around 1 in 500 (0.2%) of winter mountain travelers are avalanche professionals (e.g., paid avy instructors, paid mountain guides, professional ski patrolers who do avy assessment). If that's the number, a 1.5% fatality share would be very high, i.e., a fatality rate 650% higher than that of the total population of winter mountain travelers.

ETA: Those numbers don't reflect fatalities when avalanche professional leads non-professionals into avy terrain, the professional survives and some of the non-professionals die. An example: In the 2003 Selkirk Mountain Experience fatal avalanche, 7 clients died but the 2 avalanche professionals survived.
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gb
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gb
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PostTue Jan 10, 2017 8:16 pm 
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cartman wrote:
gb wrote:
When I look back on my own involvement and close calls regarding avalanches, persistent weak layers have always been present. With persistent weak layers the snowpack will act unpredictably, limiting the value of the application of skills.

Yet is this not predictable?  That persistent weak layers are always present whenever you've had a close call?  Unless the persistent weak layer was not detectable--too deep, perhaps--or not expected given the conditions?  An unpredictable snowpack would lead to a breakdown in the expected outcome if it is not detectable by routine methods.

You need to go back to the link at the top of the thread. There is a big difference between knowing that there might be a weak persistent weak layer or knowing that there is and knowing how the snowpack will behave when the chief problem in a snowpack is a persistent weakness.

The primary problems are the spatial distribution of the weakness, which in many cases can't be precisely known, encountering a persistent weakness that may not be expected because of micrometeorological factors, the angle (variable even for one particular weakness) at which an avalanche could release, the extent (boundaries) of a potential slab, the likelihood of remote triggering, and the longevity of the weakness. When multiple persistent weak layers exist, avalanches can also step down from layer to layer and involve ultimately a far thicker slab than might be expected. This was the case in British Columbia in 2002 - 2003 when avalanches triggered in layers closer to the surface very often stepped down with avalanche victims being caught until well into April. Some of those fatal slabs reached thicknesses of 10-12' and ended up being Class 4 avalanches.

Aware of the difficulties of dealing with this incredibly complex and dangerous snowpack the experts at Canadian Mountain Holidays responded by closing down about 1/2 of their runs that winter. It was not believed that the skilled guides would successfully deal with the weaknesses through the course of the winter.

For more information, look up ISSW papers by Bruce Jamieson. To see how Parks Canada and the educational Level I CAA Avalanche Courses changed their curriculum after 2002-3 look up Avalanche Exposure scale and Grant Statham. Frank Baumann and I actually came up with the first prototype of the Avalanche Exposure scale on Telemarktips in 2002 or 3. Grant Staham said as much in a meeting with he and Frank at a subsequent ISSW.

There are also good papers from Montana State University, Bozeman, although I forget the name of the primary researcher.
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spamfoote
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PostTue Jan 10, 2017 8:33 pm 
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I find the Heuristic traps argument rather banal.  Why?

It really amounts to someone as a leader, who has not sat down and hammered out a structured assessment tree before hand and rigidly sticks to it.  Beginning and End of discussion in my opinion.

In my opinion, due to observation, that most are not truly what I would consider "experienced".  Lets face it, back country avy territory is not gone into very often.  Even less often is: How many dig LOTS and lots and lots of different avy pits on different faces at different elevations and temperatures to test the snow and learn how the avy forecast displays itself in REALITY?  Very few.  I might even argue for NONE. 

  Then with the possible complication of group dynamics.  The dynamic of not explaining the rules of how the back country in winter time is NOT a democratic society.  Why?  You want to be "nice" as you are there to enjoy yourself and therefore do not hammer this fact home at the beginning of the trip.  Probably don't know the other guy(s) all that well so another factor of wanting to be "nice".  But, being "nice" doesn't keep you alive.  Rather what is needed, and as was taught to me: 

Winter is single ruler, with dictatorial power.  With the caveat of everyone has a veto for turning around and going home/stopping for night(though generally not true when I did it).  When my brother and I did it, we would take one day each and then switch for who is boss.  Sometimes switch via who is in lead/trailing position.  Either case: Boss man is always the REAR guy.  Not the lead.  Lead is too damned tired breaking trail.  Boss says turn around.  You turn around.  Boss says go left.  You go left.  Besides, keeps real arguments/bickering down.  Also allows the one receiving the "instructions" the time honored tradition of soto voice bitching... moon.gif

Even if you are a rigid knowledge seeker who structures their mind for winter rigors, if there is a giant weak layer 3 feet down and it decides to let loose, it doesn't matter how prepared you are.   This is akin to a giant loose rock breaking off a climbing route.  Problem is, it would appear it happens far far far far far more frequently compared to rock climbing. 

Only live once.  Is it worth it?  I keep asking myself that...
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Malachai Constant
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PostTue Jan 10, 2017 9:04 pm 
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I think of Avalanche professional as being pro ski patrol etc. the guys who drop bombs and start slides. That in my mind is a lot safer than backcountry navigation so long as you know what you are doing. Lots of knowns and not too many unknowns of course anytime you are using explosives and dealing with avalanches there are dangers but they are not the same as the traps described above.

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AlpineRose
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PostTue Jan 10, 2017 11:05 pm 
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spamfoote wrote:
It really amounts to someone as a leader, who has not sat down and hammered out a structured assessment tree before hand and rigidly sticks to it.  Beginning and End of discussion in my opinion.

MmmmHmmm.  Two out of the six heuristic traps right there.  Consistency and the Expert Halo (even if that halo has been deliberately assigned to a particular person on a particular trip).
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gb
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gb
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PostWed Jan 11, 2017 7:27 am 
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I've always thought of route finding as being in three stages:

1) Developing an initial set of expectations based on prior knowledge, recent meteorology (longer term with persistent weaknesses), telemetry and perhaps webcams, and weather and avalanche forecasts. The key is not only to choose a safe and hopefully good destination but also to develop a set of initial questions which one attempts to test. The testing is not limited to snowpack tests but focuses around observations of feel and vision.

2) The choice of destination and route in the field through discussion and observation once at the intended TH. The set of questions is further buttressed and/or modified.

3) Assuming that the tests (including further observations) continue to support the route to the destination, one then makes micro-scale adjustments to the route depending on both travel and stability clues as observed. On occasion these adjustments may be just a few yards.

Rigidity leads to poor choices, decreases the potential quality of the experience and increases risk. The goal in avalanche terrain should always be to form a set of questions to test and then to make the best effort to maintain objectivity in making observations and then to modify the set of questions as one travels to and through avalanche terrain.
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DIYSteve
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PostWed Jan 11, 2017 8:02 am 
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gb wrote:
You need to go back to the link at the top of the thread. There is a big difference between knowing that there might be a weak persistent weak layer or knowing that there is and knowing how the snowpack will behave when the chief problem in a snowpack is a persistent weakness.

The primary problems are the spatial distribution of the weakness, which in many cases can't be precisely known, encountering a persistent weakness that may not be expected because of micrometeorological factors, the angle (variable even for one particular weakness) at which an avalanche could release, the extent (boundaries) of a potential slab, the likelihood of remote triggering, and the longevity of the weakness. When multiple persistent weak layers exist, avalanches can also step down from layer to layer and involve ultimately a far thicker slab than might be expected.

Good post from a well-respected avalanche professional.

spamfoote wrote:
Lets face it, back country avy territory is not gone into very often.

Hmmmm. That begs the definition of "avy territory." If you define it as terrain with moderate or higher avalanche hazard as defined by NWAC, I must disagree. In the past 10 years, in a typical week in mid-winter hundreds of parties (mostly skiers) head into avy terrain with moderate avy danger or higher in the WA Cascades.
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spamfoote
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PostWed Jan 11, 2017 8:39 am 
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gb wrote:
I've always thought of route finding as being in three stages:

1) Developing an initial set of expectations based on prior knowledge, recent meteorology (longer term with persistent weaknesses), telemetry and perhaps webcams, and weather and avalanche forecasts. The key is not only to choose a safe and hopefully good destination but also to develop a set of initial questions which one attempts to test. The testing is not limited to snowpack tests but focuses around observations of feel and vision.

2) The choice of destination and route in the field through discussion and observation once at the intended TH. The set of questions is further buttressed and/or modified.

3) Assuming that the tests (including further observations) continue to support the route to the destination, one then makes micro-scale adjustments to the route depending on both travel and stability clues as observed. On occasion these adjustments may be just a few yards.

Rigidity leads to poor choices, decreases the potential quality of the experience and increases risk. The goal in avalanche terrain should always be to form a set of questions to test and then to make the best effort to maintain objectivity in making observations and then to modify the set of questions as one travels to and through avalanche terrain.

You just described a rigid thought structure.  Rigid decision tree logic(thought structure) has nothing to do with rigid route planning.  One subject is NOT the other.
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spamfoote
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PostWed Jan 11, 2017 8:45 am 
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DIYSteve wrote:
spamfoote wrote:
Lets face it, back country avy territory is not gone into very often.

Hmmmm. That begs the definition of "avy territory." If you define it as terrain with moderate or higher avalanche hazard as defined by NWAC, I must disagree. In the past 10 years, in a typical week in mid-winter hundreds of parties (mostly skiers) head into avy terrain with moderate avy danger or higher in the WA Cascades.

The question is not the total number of people.  The question is, how many total of that number do so regularly?  Regularly enough to understand snow pack conditions so they can interpret accurately the NWAC?  Very few.

Not a perfect analogy, but quickest I could come up with off the cuff: here goes.
It is like asking, Of the total number who climb at the Marymoor climbing rock, how many practice high angle rescue while hanging suspended?  0.00001%.  Hoards climb it daily, but next to no one practices best practices for rescue, or hold tapping for loose rocks, or being carful not to dislodge a loose rock onto their belay partner.
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hikersarenumber1
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PostWed Jan 11, 2017 9:06 am 
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It's been my experience that most people who backcountry ski back country ski a lot.

One of the biggest challenges is that the "best days" are often the "worst days"...  can you look at pure bliss, the amazing feeling if skiing untracked powder and say no, not today.  You think you can... but the number of avy deaths point to otherwise...

I had a conversation with someone whose name will not be mentioned after he triggered an injury causing avalanche about group dynamics.   I said that if anyone in a group was not comfortable with a route/slope for any reason that the group must not proceed until everyone is OK with the plan or turn back... the group operates as a reverse democracy and there mustn't be negative consequences for speaking up, other than the obvious compatibility or lack thereof for future trips...

This person, a few days after their slide, responded to me with "but then nothing would ever get skied..."

We can go around and around about it, thinking we are safer, we are aware of and somehow immune to all these heuristic traps... but when you read about the people who die, more often  than not they are just like us.
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