Avalanche Avoidance Recognising the traps

Below are two case studies based on real avalanche experiences. Read each case study and see if you can spot examples where a human factor (heuristic) trap may have had an influence on decision making? Do you think anything could have been done to avoid the traps? Can you think of examples in everyday life where your conscious behaviour has been affected by human factors?

Case Study 1: Finally the big snows have arrived. After a lean start to the season two days of constant snowfall have produced over half a metre of fresh snow. Keen to take advantage of a shared day off, 3 friends (all off-piste instructors or guides) decide to go on a short day tour to get away from the ski resort and into the backcountry. The route plan takes them steeply through some wooded hillside before reaching an open valley at the top of which a final steeper climb (30 degrees max) leads to the top of a nearby peak – about 4 hours of effort. It’s slow going with the fresh snow and already one of the party is having second thoughts about the avalanche hazard - they have never been in this area before, it feels remote and they think they have heard a tell-tale “whummph” sound (a clear sign of snowpack instability, although the tightly packed trees do not cause them to be particularly alarmed). In any case, the group is spread out so there is no-one to share their thoughts with at that point. One of the fitter, more experienced members of the team is ahead breaking trail. They are enjoying a bit of a work-out. By the time the group gather together for a short snack/drink above the treeline in a low angle, picturesque valley everyone is relaxed again.

They discuss being glad to be on easier terrain and looking forward to the next straightforward section and set off again. Some members of the group begin to assume that their ascent will now end below the final climb as conditions are uncertain and time is already marching on. Below the final climb they stop for another break and whilst each person in the group has thought about turning around at this point, they want to wait to see what the others think. The more experienced group member asks what the thoughts of the others are in terms of taking a safe line of ascent up the final slope. It turns out they all agree on a very similar line so, with just enough time to complete the ascent, they continue. Half way up the slope and close to a previously identified ‘island of safety’ there is a loud bang and the traversing skinning track forms a crown wall. A shallow but large area of snow starts to accelerate downhill taking two of the group members with it. One of the avalanched pair manages to roll beneath a boulder and out of the flow but the other continues over a convexity and disappears from view. They are not buried but are carried almost half a kilometre back to the valley floor.

Case study 2: A group of friends decide to return to a favourite area for an annual winter get-together. Near the time, a magazine article fuels their enthusiasm for a particular ‘Classic’ route which is described as one of the best routes in the area. For this group it is an ambitious objective so they plan a simple walk nearby on the first day to familiarise themselves with the conditions and hopefully to get a good view of the route.

Day 1: Although quite windy, indications are that the conditions are generally good with firm snow underfoot and the group enjoy good views of the planned objective for the next day. A forecasted cold front has not arrived by the time the team return off the hill.

Day 2 gets the team off to a slow start. They are surprised to find that overnight there has been snow in the valley and their car needs clearing. By the time they arrive at the large car-park it is almost full. Their planned route follows a summer path into a large valley before branching off steeply towards a col. There, a simple but exposed ridge leads in a spectacular position to easier terrain and a simple descent back to the car-park. The team follow a good path (firm from the passage of many boots through the ankle deep fresh snow). Winds are moderate but visibility is generally good. It is obvious that many people have headed into the mountains in the same initial direction so the group are encouraged that it’s a good day to be out. At a key point the group make a decision about their intended route. Other walkers can be seen heading most likely to the same ridge but via a longer route over another small peak. Since they are later than expected, the group decide to continue with the lower approach and one of the group states their view that the steep approach to the col will be more sheltered from the wind anyway. As they approach the steeper climb to the col they stop to put crampons on and notice another team already close to the base of a long, straightforward snow slope leading to the col. The team continue to follow the now small path (made, they assume, by the team in front) climbing more steeply towards the col. The ascent spreads the group out into smaller groups. Two of the group a few minutes in front pass the other team spotted earlier (who are actually starting a technical climb that leads through steep rocks on the right) and continue breaking trail themselves directly towards the col. About 30m below the col the slope fractures immediately above the group and both members are swept into rocks about 100m below on lower angled terrain. One group member is unharmed but the other is seriously injured and a rescue takes place.

Avalanche Avoidance

“Prevention is better than cure”. Heard that before? “Yeah, yeah,” I hear you say but if ever a cliché applied to decision making in the mountains, it would be with regard to avalanche avoidance.

You’d be forgiven for thinking otherwise. We now have easy, immediate access to a media (Go-Pro?) culture of extreme sports littered with spectacular survivals and folk who have ‘got away with it’. You’d almost be excused for thinking it had all been carefully planned and all coming at the expense of numerous other (many untold) examples where, in an instant, lives are changed forever: far from glamorous, far from any ‘high-5’s’ and far from ideal.

Even armed with the full plethora of modern technology a better outcome cannot be guaranteed. For that reason it’s worth reminding ourselves of the difference between ‘technology’ which should prevent getting caught in an avalanche in the first place (e.g. access to reliable weather forecasts, avalanche forecasts, good mapping, information sharing resources, basic avalanche knowledge) versus that which might mitigate against those uncertain consequences (airbag rucksacks; transceiver/shovel/probe; avalung; Recco; avalanche ribbons etc). Unsurprisingly, the queue for those who’ve survived one avalanche incident but are happy to experience a second is tellingly short!

The very simple and successful ‘Be Avalanche Aware’ (BAA) resource developed by the Snow and Avalanche Foundation of Scotland (SAFOS) is now, for most winter hill users (recreational and professional alike), the go-to framework to help make sound and informed decisions when embarking on winter adventures in potentially avalanche prone terrain. The model works equally well in both UK and alpine terrain/snowpacks.

Here we remind ourselves of the basic BAA concept and how it applies to avalanche avoidance as well as a more detailed look at some human factors, or heuristics, which have been shown to play a significant role in associated decision making.

One thing that can often be off-putting for those new to the winter environment is a concern that lack of knowledge prevents good decision making. One of the strengths of the BAA model is that it guides users through a series of relatively simple questions that require fundamental but basic levels of skill and should be achievable for anyone with basic hill and mountain skills.

The snowpack in the UK often differs markedly from that in alpine regions and therefore the scale and type of avalanches that commonly occur can be different. Many forecasts will use recognisable terms and phrases such as slab, loose snow, propagation over larger areas, terrain traps, remote triggers. You should understand what these terms mean and try to picture the shape and scale of possible avalanche activity.

The UK mountains tend to offer such a wide variety of options in terms of routes and journeys that a relatively safe option can usually be found even on days with higher levels of avalanche risk in certain places. This luxury is not always available to those following itineraries in alpine terrain where often the path of least resistance has already been identified and short sections of critical terrain cannot be easily avoided. For this reason ’commitment heuristics’ can play a much greater role in decision making (more of which later).

Almost all avalanche avoidance begins with thorough planning and preparation and the BAA model directs us to three simple components: Weather & Conditions; You & Your Party; the Mountain Landscape.

Planning might begin several days before a trip when you begin to study the relevant forecasts (both weather and avalanche) as well as gathering information about the intended area you wish to visit via maps, guidebooks, articles or online resources and consider the skills and experience of you and any group you may be part of. Two or three days beforehand you hopefully have a general idea of what current conditions are like, how they relate to you and/or your group as well as any anticipated changes going into your own trip.

With a general overview of conditions, weather and aspirations it’s time to look in more detail at formulating a Plan A (and B?). Maps can be studied in more detail and additional general observations should be made once you have arrived in the chosen area – it’s very useful to be able to form a picture of your intended environment.

The detail of the plan should now include identification of any key places or times during the day. Easily remembered as ‘3 A’s’ (Angle, Aspect, Altitude), this includes any particularly steep areas of ground (avalanches release most commonly in zones between 30-45 degrees) along with aspects (relating to prevailing wind or sun)or altitudes that may have been identified as presenting heightened avalanche risk. Other key points can be times of day when significant weather events begin to change conditions or, particularly in alpine climates, when temperatures may start to play a critical part in snow stability.

At the planning stage you will have a better chance to consider reasonable alternatives or plans of action and thus create reminders for use on the route itself. There would be an assumption here that the planning team will have the skills to interpret maps and guidebooks successfully so don’t ignore the importance of basic mountain skills that underpin the entire process. A final point worth noting is that it can be useful to rate any plan in terms of its sureness. Some plans will, by their nature, have a large degree of tolerance in terms of being executed without hiccup and can therefore cope with larger variations should expectations not be met. Other plans may be more ambitious, so will need earlier intervention should conditions change.

So the big day arrives and the planning can start to be applied! In an ideal world everything (from the mood of the party to the conditions that are encountered) will more or less be as anticipated – that’s the first good sign. Simple observations: “It’s not as windy as expected”; “It feels warm”; There’s a lot of fresh snow blowing around”; “There’s not much snow on that side”; “It’s really busy”, should all be noted. Try to consider what, if any, effect this may have on your plans (particularly with respect to the key places already identified). Uncertainty can always lead to a feeling of anxiousness and for those with less confidence this early point in the day can seem a bit daunting but have some faith in the planning that has been done before. Don’t confuse being open-minded with being uncertain (or vice versa)! Having said that, some days present clues from an early stage that all is not as the weather /avalanche forecasts have predicted and plans, especially the ambitious ones, may need to be tweaked from the outset.

So, usually with a few tweaks here and there, the journey goes as expected. Again, having done a thorough planning exercise there should be plenty of observations to cross-reference as a check – with the BAA model again prompting you along the right lines: Weather & Conditions; You and Your Party; Mountain Landscape. Make sure you make these observations and share them throughout the group – is everyone picking up on the same things? If out on your own, try talking to yourself. It’s much harder to ignore or fail to pick up on your thoughts if they are verbalised either internally or out-loud and this can help avoid some human-factor (heuristic) influences.

Key points that have been identified at the planning stage then become the focus of further decision making and review. For example, the early onset of bad weather (e.g. wind; snowfall; rising temps) identified in the planning phase may not be an immediate issue but in only a short time conditions can change markedly. Conversely, a time critical plan dependant on negotiating certain slopes before the sun arrives, can suddenly become more relaxed when a cloudier than expected day might delay the onset of warming. Key points also give an opportunity to reflect on the possible impact of human (heuristic) factors.

As you approach key points during the day it’s worth being proactive in trying to anticipate what you will find. Are snow quantities as expected, is it likely to be windier, less windy, in the shade or the sun. The onset of darkness might be the key point. Are you a confident navigator? Have you got time to reach the summit and return before navigation becomes more challenging? Can you cope in whiteout conditions?

Human Factors

Alongside a decision making framework such as BAA, it is well known that even high levels of avalanche education/awareness can be over-ruled or ignored by simple primal human tendencies. Theses human factors (or heuristics) can significantly influence the decision making process and are very hard to mitigate against as many feature a subconscious component that can be hard to spot let alone quantify. An awareness of how they can impact our decisions offers some protection particularly if we force ourselves to reflect during our later planning stages or at any key points phase during the journey.

Some of the main human factors (heuristics) can be summarised as follows – each with examples of how they might present themselves as conscious thoughts or words:

Commitment – “we’re so nearly there. If we can just….”

“If we turn around now it’ll be disappointing for everyone not just me”

“So far so good, well done us!”

Ironically, a thorough planning phase will already stack a certain amount of commitment to undertaking a particular journey. This could be both the time, energy and effort of planning as well as the physical execution. Nobody likes to call into question their own judgement – especially when so well thought out(?) instead preferring to believe that a behaviour is correct because decisions that have brought you to that point prove it. As a journey continues the commitment heuristic is therefore enhanced. A key defence against this trap are the key points identified earlier in the BAA process. Each key point should trigger a comprehensive and open-minded re-evaluation of the plan including conscious or deliberate consideration of how much has been invested in the trip thus far and whether that is likely to have an effect on the desire to continue. It should also be an honest reflection on how much of the decision making has gone to plan and how much has been in reaction to unexpected events.

Scarcity – “Half-term will be my only chance to go winter walking this season”

“I want some fresh tracks today”

“It will be safer to get to the route first”

Unlike our planning phase which sets out to channel our options towards good or preferred outcomes (or to identify specific areas on the mountain to avoid), the scarcity heuristic could be described as behaviour arrived at due to the imposition of barriers or restrictions to our enjoyment. Our decision making becomes skewed to the extent that we overvalue our motivations or even actively rebel against what we know to be sound decisions.

Familiarity – “I’ve never seen an avalanche there”

“That run has been great all week”

“(location) is a good choice in bad conditions”

Repetition of the same or similar decisions at the same or similar venues often puts us at risk of short-cutting the decision making process (and potentially missing critical bits of unique information). Ironically, this may be a greater factor for those most regularly making avalanche avoidance decisions. We should try and ensure that our decisions come from the full evaluation of each set of circumstances – even though this can at times seem a bit tedious. Again, the use of key points can offer pre-determined opportunities to re-look at the environment and group from a fresher perspective.

Social Proof – “No-one else seems uncertain so it’s probably just me”

“Other folk have the same idea so it can’t be bad?”

“I’m not going to be the one who says I’m nervous”

Sometimes it can be advantageous to refer (defer?) to the actions of others in an effort to arrive at a sound decision but always ask yourself what may be influencing their decisions. It always tends to feel better when other people have chosen a similar option but it can be very hard to determine whether actively conforming or deliberately avoiding an existing behaviour has advantages or not . Even within a group, some members can be swayed by complicated dynamics within the group and create a skewed consensus. The subtle difference between peer encouragement and peer pressure would be one example of this.

Visit www.glenmorelodge.org.uk for further information on avalanche avoidance and details about Avalanche Awareness courses.



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