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NSAW & Avalanches - 2015 Update



NSAW & Avalanches - 2015 Update
by Andy Dappen


Over 600 backcountry skiers and snowboarders attended the Ninth Annual Northwest Snow and Avalanche Workshop (NSAW), Sunday of November 8. The day was dreary and drizzly, making the indoor presentations a fine and pleasant way to learn while sipping coffee. The preponderance of attendees were Wet siders, but at least few dozen old school skiers and nearly as many new school skiers from the dry lands east of the Cascades journeyed to Seattle to plump the skin with humidity and the brain with information. Here is a brief recap of what I found to be the most interesting presentations. I saved the best for last so go there now if your time (or attention span) is short.

Kyle Van Peursem, who has been conducting avalanche research at the Montana State University, discussed different ways of collecting weather data (actual observed data from the field versus automatically collected data from telemetry sites) and running Snowpack modeling from this data. Snowpack modeling built from the data off of telemetry sites was not as accurate as modeling from sites using the direct observations of snow forecasters, but this research showed that good telemetry combined with good modeling still delivered fairly accurate information about snow types, snow structure, and stability. Such information would still be very useful if it came from different corners of ranges like the Cascades where we still have large voids of information.


Photo by Mike Rolfs. Matias Rodback examining BIG hoar frost crystals on the bottom of a block that slid while testing snow stability.

Margaret Wheeler
, a fully-certified UIAGM mountain guide based out of Seattle, discussed how avalanche education and information so often leads skiers to over-confidence and over exposing themselves to danger. Wheeler stressed that avalanche education still hasn’t found its stride in keeping skiers from being overconfident and over exposed. She discussed interesting intuitive and cognitive systems we use and that are taught to heighten our safety, but told how these tools often talk us into skiing something rather than out of skiing it. A technique Wheeler intends to experiment with this winter is opposite to the way we usually think. Rather than assuming a slope won’t slide and proving the opposite to prevent her from skiing it, she intends to assume a slope will slide and will need to prove the opposite to go ahead and ski it. She hopes this will lead to a more conservative mindset and a more rigorous evaluation of conditions. This may also lead to a more accurate weighting of uncertainty -- in this case, uncertainty leans toward not skiing a slope because uncertainty does not help prove stability.

Heiko Stopsack, a King County paramedic who often assists in the rescues of backcountry travelers, discussed hypothermia preparedness among skiers. Each year about 1,300 people die of hypothermia in the United States versus an average of 39 yearly avalanche deaths in North America. These are not apples-to-apples statistics (far more people die of hypothermia out of the backcountry than in the backcountry) but it is safe to say that hypothermia is a far deadlier killer in the backcountry than avalanches, so we need to be properly prepared. Backcountry accidents requiring a rescue can take a long time to activate. Often injuries occur late in the day or in poor weather so it will require at least 12 hours for rescuers to arrive on the scene. And this raises important questions. Within your party do you have the shelter (e.g., tarp), tools (pruning saw to cut wood, fire making materials, metal container to heat water), and clothing to keep a badly injured person warm this long? Will other members of the party be able to stay warm? The Alaska Hypothermia Guidelines and international guidelines were also discussed -- these have guidelines to determine when the victim of an accident has such a small chance of revival that it was not worth risking the lives of others to activate a rescue.
       Note: This sobering presentation had me thinking ALL backcountry skiers who have never bivouacked with what they routinely carry in their day pack should do a test run with their ski partners. Head out on a foul-weather ski tour with each person carrying his or her standard kit (don’t fudge here). At the end of the day (and fairly near the car), simulate an accident in which you dig someone out of a hole, splint a broken leg, and spend the night out. The exercise will expose big holes in the preparedness of most teams.

Susan Joslyn, a psychologist working at the University of Washington and researching how people make decisions in the real world, presented research findings about how the public responds to weather forecasts, what information the public needs to make better decisions from these forecasts, and what information gives the public more trust in forecasters. The information was not of direct help to backcountry skiers but had interesting implications about how the Northwest Weather and Avalanche Center could present weather and avalanche forecasts with different numerical expressions of uncertainty that could help skiers make better decisions.

Pascal Haegeli, an avalanche researcher with Simon Fraser University in British Columbia, discussed the statistical analysis of avalanche accidents that helped his team quantify the effectiveness of avalanche airbags. Statistically this is not an easy task, but by using the data from avalanches that captured skiers using airbags as well as skiers who were not using airbags, the research indicates that airbags are capable of cutting fatalities in half when skiers actually deploy the airbags (sometimes pilot error keeps those caught in slides from getting their bags deployed). Haegeli emphasized that airbags are not silver bullets. While deaths rates can be cut in half, some airbag users will still get buried and suffocate while others will die from the trauma inflicted by a slide. Incidentally, Haegeli’s data showed that, per 100 skiers caught in avalanches big enough to bury people, 22 people died if they did not use airbags while 13 died using airbags -- of these 13 only 11 would have died if all them had actually deployed their airbags).

Martin Volken, a Swiss mountain guide who owns Pro Guiding Service and Pro Ski Service in North Bend, gave the presentation that several of us sitting together agreed was the most useful talk of the day. Volken said careful tour planning that incorporates the forecasted weather and avalanche conditions can reduce the likelihood of avalanche accidents by as much as 80 percent. Nonetheless, skiers need easy systems for on-the-go decision making.

Volken’s system for hazard evaluation and decision making applies to virtually anything -- climbing, investing, combat and more. When applied to avalanches, however, you would give both the ‘Likelihood’ and the 'Consequence' of a slope that could avalanche a number between 0 and 5. For example, for the Likelihood Scale you might use the following gradations 0) no likelihood, 1) low likelihood, 2) moderate likelihood, 3) considerable likelihood, 4) high likelihood 5) extreme likelihood. Meanwhile the divisions of the Consequence Scale might break down like this: 0) no consequence 1) no injury, 2) bruises/scares/embarrassment, 3) strains/sprains/lost equipment but travel is still possible, 4) broken bone(s) or trauma requiring a rescue, 5) death likely. 

Now, for any slope you're evaluating, give it a number on each scale and take the sum of these two numbers. Volken says if your total is 6 or higher, you are in the process of making a dangerous decision. Naturally, many skiers are lucky enough to survive quite a number of incidences where the combined sum of their two scales is 6 or greater, but frequent exposure to such scenarios is a process relying on hope and is not a long-term recipe for survival.

When the total of the two scales is 7, the decision for most teams will be clearly a no-go. Meanwhile a total of 5 will be a green light for most parties -- although such a number should heighten the party's use of safety protocols.

A total of 6 is a slightly grayer zone and skiers respond to this number differently because they have different risk tolerances. A likelihood of a slide being a 5 with the consequences being a 1 or the likelihood being a 1 but the consequences being a 5 may be acceptable to some skiers, unacceptable to others. Meanwhile different combinations of numbers from each scale resulting in a 6 may evoke different responses from the same person. I would be far more willing to ski slopes that were rated 6 through some combination of a 5 and 1 on the LC scales than through a 3 and a 3 on the LC scales.

Despite some personal customization around the number 6, Volken maintains the benefit of doing this analysis is its objectivity. If, after doing the math, you still want to ski terrain whose number is 6 or more, it’s far easier to identify subjective variables affecting your judgement. Is the pressure to get home by a certain time forcing you to hurry and clouding your decision? If you back down are you worried about disappointing people you want to impress? Are you being driven by the desire to grab first tracks or the recognition of a first descent? Volken calls all of the human factors that pull us toward dangerous decisions "lateral shifts" – something else is moving us away from our objective look at the situation. With this system, however, if the number is greater than 6 (or even if it equals 6) and you're still wanting to ski the slope ahead, you need to examine your motives. What’s compelling you to ascend or descend dangerous ground?

Uncertainty about the snow conditions or the consequences can also be built into the LC scales. For example, if you don’t know the stability of the deeper layers in the snowpack, you should take what you do know (the amount of new snow, how the upper snow is bonded, the steepness of the slope, etc.) and ‘up’ the Likelihood number you’ve calculated by a digit. And in this example, if a deep slide were to occur the consequences would be greater -- so you may need to ‘up’ the consequences number as well.

This system was simple, practical, and objective enough that, on the drive back to Wenatchee, Mike Rolfs said he was going to make a Likelihood-Consequence graphic and laminate it to the top of his skis. Whether skiing alone or with others, this would remind him to use the tool and would make his decision-making more objective.

"Brilliant idea," I told him. "You're taking the best idea from NSAW and giving it legs."