I wasn't out climbing today, which was a shame because it turned out to be a nice day for ice climbing. Friends of mine were out climbing The Cascade and Green Gully on Ben Nevis. Both were thin but gave good fun ice climbing. After two and a half weeks of soggy, relatively warm weather, we are finally starting to get more normal weather and temperatures for the time of year. The big high pressure is finally moving away, taking with it the stream of air from the Canary Islands that has slowly melted away some of our snow and ice. In its place, low pressure systems will sweep across Scotland bringing strong winds and fluctuating temperatures, and plenty of precipitation. This is good news (honestly). Our most common and most famous style of winter climbing is snow-ice climbing in gullies. Point Five Gully is possibly the most famous example and is well known the world over. Green Gully and Comb Gully on Ben Nevis, Crowberry Gully on Buachaille Etive Mor and SC Gully on Stob Coire nan Lochan are also snow-ice climbs. Snow-ice does not form just with cold weather. Instead we need snow fall and the right direction of wind to fill the gully with snow; just enough thaw to make the snow wet without melting too much away; then a good freeze to make it solid. This snow-thaw-freeze cycle needs to be repeated a few times to form sufficient snow-ice in the gully to climb. Too little thaw before the freeze will result in firm snow rather than solid snow-ice, or a surface layer of snow-ice on top of softer snow. Then we need a calm day with no snowfall and a freezing level below the bottom of the route for it to be in condition. The West Coast of Scotland typically benefits from lots of snowfall accompanied by strong winds and temperatures that can change by 10℃ in just a few hours (and sometimes back again in the next few hours). Soft snow is transported by the wind to collect in sheltered slopes and is funnelled by gullies. It is warmed up in the following thaw and becomes wet from partial melt or through rainfall. It then freezes into a more solid version of snow if there is a subsequent freeze. This is how snow-ice is formed and the quality of the snow-ice depends on the precise balance of volume of snow, depth and duration of thaw, rain, and how well frozen it is afterwards. With very little change in any one of these variables, the quality of the resulting snow-ice changes greatly. At it’s best, snow ice can offer the perfect combination of plastic, dependable ice that does not shatter when you place a pick but is sufficiently solid to place good ice screws into. The “honeycomb” structure provided by millions of tiny air pockets in the snow creates a texture that absorbs the strike of a pick instead of shattering like cascade ice. At its worst, a snow ice climb can be vertical snow that is too soft to hold an ice axe, let alone an ice screw. How do you know if the balance is just right and the snow-ice will be perfect? Well, that comes with practice, and a lot of checking forecasts and actual weather data. It looks to me like the weather forecasts for the next week or so, combined with the snow and ice cover we already have, the background temperature of the rocks and the amount of water in the rocks from recent rainfall, all add up to a good ice building period coming our way. Fingers crossed!
Here are some useful resources to track progress. Mountain Weather Information Service - https://www.mwis.org.uk/forecasts/scottish/west-highlands Met Office - https://www.metoffice.gov.uk/weather/specialist-forecasts/mountain/southwest-highlands Scottish Avalanche Information Service - https://www.sais.gov.uk/lochaber/ Weather data from Aonach Mor at 1200m - https://holfuy.com/en/weather/1365 Weather data from Aonach Mor at 900m - https://holfuy.com/en/weather/195 Weather data from Aonach Mor at 650m - https://holfuy.com/en/weather/296 Weather data from Glencoe Mountain (Meall a’Bhuiridh) at 360m, 750m and 1100m - https://www.glencoemountain.co.uk/weather/ Webcam images and weather data from CIC Hut, Ben Nevis - https://www.smc.org.uk/cicwebcam/cic_weather.php
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After a week of green avalanche forecasts it might not be the best timing to talk about brushing up your knowledge and skills. Then again, the climbing is a bit limited right now so perhaps it is the perfect time to put a bit of effort into understanding how we can avoid being avalanched. We are blessed with a good number of excellent resources at our disposal and there is a new one out today. A new online avalanche awareness training initiative has been launched by The Snow and Avalanche Foundation of Scotland (SAFOS), with development support from member organisations Mountain Training Scotland and Glenmore Lodge. Aimed at individuals making critical decisions in the winter mountains, this free digital version of the ‘Be Avalanche Aware’ planning tool will enable hillwalkers, climbers, mountaineers and skiers to be more aware of the avalanche risks and the factors that influence their planning and journey decision making. Avalanche education has changed completely in the time that I have been working as a full time guide (22 years). Now, there is a focus on how to read an avalanche forecast and weather forecast to make decisions in the planning phase before you head outside. 70% of our decisions should be made in advance, and our observations on the day should confirm these decisions, while also being open to differences in the forecasts and what we observe and being able to react and change plan accordingly. Modern avalanche education like this reflects the fact that people who get hurt in avalanches often do so as a result of human factors influencing their decision making, not things to do with their understanding of the avalanche hazard. These heuristic traps or cognitive biases are very powerful and often go undetected by us as we enjoy our days in the mountains. Having a process to help us make decisions without human factors influencing us is very important. To take this even further, we also have James Thacker's excellent Crew Resource Management training. Crew Resource Management, a term first used in aviation, was introduced to mitigate the affects of heuristics and other human factors, but have since grown to encompass many ‘non technical skills’.
Non technical skills for skiers and mountaineers include: situational awareness, decision-making, teamwork and communication, leadership and task management and the application of these skills in the winter environment. For leaders, instructors and mountain guides working in the winter mountains, CRM behaviours and non technical skills can be used alongside existing decision making frameworks such as ‘Be Avalanche Aware’ (BAA). The winter mountains may not be your work place, but some of the behaviours and non technical skills will almost certainly be relevant to lots of recreational user groups in the mountains. Last weekend we had a lovely time in deep fresh snow with rime on the rocks. I was at Nevis Range with my kids trying to remember how to ski. Monday was a much warmer day with rain to the summits. Some big avalanches came out of Number Five Gully and Number Two Gully at some point leaving behind some impressive debris. The Number Five Gully debris was big enough to bury my van. Tuesday was slightly better, a bit colder and drier. I climbed Number Three Gully Buttress with Connor and Sam which was great. Other teams were out in Number Two Gully, a mixed ascent of Comb Gully Buttress and Gargoyle Wall which was frozen and verglassed but not very white. Yesterday (Wednesday) was warmer again and more drizzly. I went up Tower Ridge as far as the Eastern Traverse with Joe and Alex. Tower Ridge has a good cover of snow on it. The narrow ridge just above Douglas Gap is covered in a slender crest of snow and there is deep snow all the way up to the Little Tower. All this snow was useless for climbing on, being softy and very soggy, but it is good news for when it freezes. At the Little Tower we started to find ice on the rocks as well as useless soft wet snow. This is not an ideal combination for climbing and it felt a bit awkward in places. I'm glad that I know the best way to go. We were exploring details on the route up Tower Ridge including alternative access routes to the start of the ridge and how you can get off. We went along the Eastern Traverse and continued traversing until we were underneath Tower Gully. This is a really good way off the ridge if there is a problem, but might just take you into different problems if there is an avalanche hazard. There was no avalanche hazard yesterday, just lots of deep wet snow. There is some ice around. Smith's Route had a bit of ice on and there was ice on all the rocks above 1000m or so. This week gave us merciless ming. Nobody like Ming the Merciless but we need it to consolidate the snow and make ice. When it gets cold again all this wet snow will freeze solid and ice will build rapidly. When will this be? Well, it looks a bit colder on Saturday, but it is uncertain what will happen after that!
There is a wonderful world of single ice axe mountaineering to enjoy here in the Outdoor Capital of the UK. Our first Classic Winter Mountaineering week has coincided with a rapid return to cold and snowy conditions after a big thaw at the weekend. Rupert and Tom have been enjoying some excellent days out with our mountaineering and climbing instructor Dave, and a useful but less comfortable day out today in the rain! Ledge Route on Ben Nevis was a perfect start to the week. The drop in temperature on Sunday night and during Monday was remarkable, and there was ice and a little snow on the rocks by the time the team got there. Ledge Route has an awkward rock slab low down on the climb that had enough ice to make it difficult, but not enough ice to be useful for climbing. The tricky theme continued for the rest of the way up the ridge as well. A little snow on the rocks covered the hand and foot holds but was not useful for climbing at all. Despite all this the team got up the route very well and descended Number Four Gully back down into Coire na Ciste, looking at ways to safeguard descents with the rope. Tuesday was a bit more windy and cloudy so the team went to climb Curved Ridge on Buachaille Etive Mor, a fantastic, long route that stays well sheltered from the wind most of the time. As well as climbing these routes, Rupert and Tom are keen to learn the ropes, the techniques and skills for future winter mountaineering. Dave has been teaching them all sorts of useful things to take them from winter walkers to winter mountaineers. When the weather is good and there is fresh snow on the ground, there is nothing better than a traverse of an t'Aonach Eagach in Glen Coe. Standing proud above the glen and reaching down the length if it, the Aonach Eagach is a mountaineering must do. It is several kilometres long, committing, exposed and brilliant. Being able to move sufficiently quickly whilst also making sure it is safe enough is the balancing act you need to do, just as much as balancing act along the narrow crest of the ridge. So, after three superb days of burly wintry goodness, today was a different kind of day altogether. Heavy rain, snow above 900m and very strong winds battered Scotland. The west coast does seems to enjoy the worst of the storms and we need the storms to bring the snow and pack it into the gullies and corries, as well as the rapidly changing temperatures needed to consolidate the snow and hold it in place. We do need to endure the January storms, but enduring them is not much fun sometimes. So, Dave and the guys spent a very useful day learning more about avalanches and how to avoid them, and in doing some more technical ropework in Glen Nevis when it brightened up a bit this afternoon. And Glen Nevis is on the cards for the team tomorrow as well. Stob Ban, a beautiful pointy peak in the Mamores, is most likely where the team will finish the week, enjoying the East Ridge of North Buttress and traversing the summit. We have another Classic Winter Mountaineering trip in the spring (11th to 15th April) when the conditions will be very different. It will be interesting to see how the two weeks will compare, one at the start of the winter and one at the very end, but equally good in different ways.
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AuthorMike Pescod Self reliance is a fundamental principle of mountaineering. By participating we accept this and take responsibility for the decisions we make. These blog posts and conditions reports are intended to help you make good decisions. They do not remove the need for you to make your own judgements when out in the hills.
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