Bill O'Connor

Alpine Ski Mountaineering Vol 2 - Central and Eastern Alps


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skiers completely buried by an avalanche only 4 in 10 survive.

       Over a recent period 1347 people were known to have survived partial or complete burial by avalanche. Of these:39% dug themselves out34% were dug out by survivors on the scene27% were recovered by rescue teams – but most of these were near ski resorts.

       In that same period close to 1000 died – two-thirds by suffocation.

      The Three Essentials

      To maximise speed of rescue there are three ‘must have’ bits of equipment for every off-piste skier and ski tourer.

      Transceiver – Owning one will not stop you getting caught in an avalanche, but if you are buried it is almost your only hope of being found – dead or alive. A transceiver is not a substitute for good practice, it is part of it. Route planning, route choice and constant avalanche awareness are the basic ways to minimise risk.

      Every skier going off-piste or touring should have a transceiver. However, it is not enough to own one: you must wear it and know how to use it in an emergency. That skill only comes from practice, regular and realistic practice against the clock – remember the first 12–15 minutes are all-important. Get into the habit of turning your transceiver on when you put it on in the morning and leaving it on until you return in the evening. Never turn your transceiver off during the day to save the battery. It is all too easy to forget to turn it on again.

      Having turned your transceiver on make sure you carry out a transceiver check both on leaving the hut and at other times during the day, especially after rest stops. Rather than standing around in a huddle and checking transceivers work when you are standing next to each other, get one person to ski away (say 30m) from the group with their transceiver in receive mode. Then one at a time the group members with their transceivers in transmit mode ski towards the person on receive. As soon as the person receiving picks up a signal they should signify it. This gives a good indication of signal strength, which seems to vary amongst different makes of transceiver. Someone should then check that the person on receive is also transmitting correctly. Everyone should carry spare batteries on a long tour.

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      Digging a snow pit and looking for weaknesses in the profile

      Snow shovel – It is not enough to have one or two shovels in a group of four or six skiers. Everyone should carry an avalanche shovel. One reason why I like touring with North American clients is the size of their shovels! They carry big metal-bladed things that can shift snow fast, not flimsy things the size of desert spoons. This really is a case of size being important. Don't bother with tiny blades that attach to ice axes or ski poles that bend the moment they come into contact with hard snow. If you were buried what would you want your rescuers to use? A JCB!

      Avalanche probe – Used in conjunction with a transceiver avalanche probes can quickly establish the exact position of a body before initial digging. For a final search or deep burial they are a must.

      They are also useful for testing the snow structure by probing rather than digging once you know the snow profile on a given aspect. This can be particularly useful when on the move.

      But it is not enough simply to carry these essentail tools, you have to know how to use them in an emergency. Practise regularly.

      Assessing Snow Stability

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      Reusch block test

      There is a lot you can do to assess snow stability before you go on tour. Snowpack is the result of past snowfall and weather conditions, and you need this information to understand how it has built up. Weather reports, avalanche bulletins (see the Avalanche Bulletins box below) and web sites provide an often detailed picture of what conditions have been and are now like on the hill. Tourist Offices and Guides Bureaus, as well as knowledgeable locals, can all provide additional information.

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      Once on tour you need to evaluate snow stability constantly because the slope aspect, altitude and conditions are always changing. To some degree ski mountaineers gain a feel for slope angle, snow and conditions – it's called experience. I find it helps to have a procedure when evaluating snow stability. Aim to gather targeted information that will help you build up an informed picture. Eliminate unessential information and go straight for the bull's-eye.

      Above is a checklist for assessing snow stability similar to those used by British mountain guides and avalanche professionals around the world. I'm always surprised how easy it is to overlook obvious signs of both danger and stability. The checklist is useful as an aide-mémoire to help systematically observe, test and record pertinent information and so build up a profile of snow stability at a particular time and place. This information provides a more complete picture when the time comes to make a judgement about avalanche danger.

      Obviously some techniques here depend on knowledge and skill. Snow profiling and various stability tests, including the shovel shear test and Reusch blocks, although quickly learned, require training in interpretation. Anyone committed to ski mountaineering would be well advised to attend some kind of avalanche awareness training course where they can learn these skills.

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      Crown wall over 2m high across a slope regularly traversed by ski-touring parties

      Stability tests need to be carried out regularly. Although they can seem like a chore they do not take a great deal of time and they provide essential information. Once armed with the information in the chart above the picture of snow stability becomes a lot clearer. It may not be perfect, but it is better than a piece of seaweed or the ‘It must be stable because someone else has skied it’ approach to avalanche risk assessment.

      Having made an assessment you can then modify your route or procedures on tour to maximise safety.

      AVALANCHE BULLETINS

      There is a wide range of information that can be accessed via telephone, fax and the internet during the ski season. The following list covers the major Alpine areas described in this book and will help you gather information before and during a tour.

      France

      Telephone: Dial International Code (0033) followed by 89 26 81 020 and the department number:

Haute Savoie 74
Savoi 73
Isere 38
Hautes-Alpes 05
Alpes Haute-Provence 05 or 06
Alpes Maritime 06

      Website: www.meteo.fr/temps/france/avalanches

      Italy

      Telephone: Dial International Code (0039) followed by (0461) 23 00 30. When phoning from outside Italy leave the 0 off the number in brackets:



Valle d'Aosta www.regione.vda.it/bollnivometeo.nsf (0165) 77 63 00
Piedmonte www.regione.piemonte.it/meteo.neve.htm (011) 318 55 55
Trentino www.provincia.tn.it/csvdi.bolletino (0461) 23 89 39
South Tirol www.provincia.bz.it/valanghe