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Two faces of nature Avalanches are part of the alpine environment; minimizing the danger requires knowledge and preparation By G.D. Maxwell The day is sunny and warm. The snow is softening in the sun and responsive to every move you make.

Two faces of nature Avalanches are part of the alpine environment; minimizing the danger requires knowledge and preparation By G.D. Maxwell The day is sunny and warm. The snow is softening in the sun and responsive to every move you make. It’s spring skiing at its finest and you feel bolder with each run. You ski steep pitches with ease and your turns are perfect. Only problem is, the slopes are getting pretty worn with traffic. At the top of the mountain you bump up against the ski area boundary. Beyond the rope, the slopes seem endless and perfect. New tracks blend with some old but clearly few have gone before. This pitch is yours for the taking. A quick look over your shoulder and you duck the rope to poach a run. Cutting a long, high traverse to the centre of the field, you make your turn. Your skis and boots disappear, swallowed by snow starting to move around them. The slope you’re on is sliding down the fall line and you’re going with it. You lose your balance and fall. Your world is going downhill. You roll and tumble and struggle to keep up distinguished from down. You can’t stop because everything is moving around you; there’s nothing to grab on to. You slide forever and eventually stop. You see daylight; you’re on top of the snow. Luck winked. You’re alive. The alternative is darkness, contortion, impact, and the weight of a couple of tons of snow slowly crushing the life out of your lungs. Death in an avalanche. Avalanche. The word itself seems to have a mystique surrounding it. Whistler Brewery named a Pilsner after it. Colorado has a hockey team bearing its name. Sierra Designs fashioned a line of clothing in its honour. It evokes strong images of two faces of nature: one minute serene and timeless; the next, boiling with strength and anger, wreaking havoc and destruction. Avalanches are a constant danger to those who play in alpine environments. Skiers, climbers, snowmobilers, backcountry travellers, motorists, are all at risk of avalanche. In the winter of 1996/97, they have so far taken the lives of 17 people in Canada and the United States, four in British Columbia, three in our own backyard. On Dec. 17th, three heli-skiers were buried and killed on the snow fields nearby. They were skiing relatively stable slopes when a fault in the snow opened from the surface to a hard rain crust deep in the pack that had been set up in November, a month before. The side of the mountain slid in an instant and took them with it. Guides homed in on their transceiver signals within minutes but the force of our heavy, Coastal snow suffocated them in the 40 minutes it took to dig them out. Last winter, 27 people enjoying outdoor recreation were killed in avalanches in the US. Included in their number were a ski patroller at Solitude Ski Area in Utah and a heli-ski guide in Ketchum, Idaho, professionals who understood the dynamics of snow. Also included in the numbers were two German climbers killed on Mt. Hunter — Denali’s neighbour — in Alaska. A team of four climbing buddies arrived at Denali in May, wanting to climb. Permits to climb Denali need to be arranged 60 days or so in advance. The Germans protested they should be allowed to climb even without a permit. The US Park Service explained there were already 200 climbers on the mountain and denied their request. In frustration, the team chose two routes up Mt. Hunter. Not having the cachet of Denali, Hunter attracts less traffic and requires no permit. Two climbers with "extensive climbing background in Europe," according to a survivor, picked a difficult, avalanche-prone route previously scaled by only a few highly experienced mountaineers. They chose wrong. When it was all over, the surviving climbers blamed the Park Service for the deaths. Snow doesn’t care what you know or who made the mistake. Snow’s not impressed with how smart you are or how many successful trips you’ve taken into the backcountry. Snow’s indifferent to the advances we’ve made, the insights we’ve gained into the science of snow, weather, physics and avalanche modelling. When the conditions are right — and there are so many right combinations — snow lets go. It lets go in two different ways: loose snow avalanches and slab avalanches. In the Rockies and other continental ranges, dry powder snow and a relatively shallow snow pack form perfect conditions for loose snow avalanches. These start at or near the surface, at a single point, and spread out as they flow downhill, generally forming a triangular pattern and involving snow at or near the surface. By contrast, in the Coastal mountains, we experience a much greater volume of snow and more varied snowfall, sometimes wet and heavy, sometimes drier and lighter. Over the course of a season, our local snow pack will be a complex strata of cold loose snow and warm heavy snow, ice, rain crusts, sun crusts and hoar frost. When snow slides around here, it’s almost always in the form of slab avalanches. Slab avalanches generally happen somewhere in the depths of the snow pack. A weak layer of loose snow or a lubricating layer of crust allow the surface layer or layers of snow to slide as a whole — usually a rectangular block and sometimes of massive proportions — until it is stopped by intervening natural barriers or reaches a less steep runout. More often than not, the trigger for slab avalanches is the additional weight of new snow loading the pack. Around here, we all know what a good overnight snowfall means: big lineups to be first on the mountain, early morning serenades of high explosives echoing through the valley, and frustrating waits while the ski patrol completes avalanche control. Judging by some of the comments you can hear on and at the base of the mountains, you’d think the only purpose of avalanche control was to spoil some people’s day. And ironically enough, much of the grousing seems to come not from the tourists but from locals who know the mountains well and know exactly where they want to head for fresh tracks. It’s ski patrol’s job to get as much of the mountain open as soon as it is safe to do so. On Whistler Mountain, the avalanche control job comes under the direction of Anton Horvath and Jan Tindle. Far from waiting until a big snow day, the job begins when the snow starts to fall in October or November. "We start monitoring the pack early in the season, observing how the new snow is bonding with the old, watching for weaknesses between layers. Deep weaknesses, like November’s rain crust, are carefully monitored," Anton explained. Weather observations — temperature, snowfall, freezing levels, wind speed and direction — are collected at several plots around the mountain. Careful records are kept to build a history of the season’s snow pack. As well, information is collected from and shared with others. "Aside from my own observations, we rely on other patrollers who monitor the pack around the mountain, on Blackcomb’s patrol, and the heli companies," Anton said. "When they fly, we get information from them; when they don’t, they get information from us." The interaction between historical, overnight and current conditions is what determines the protocol for avalanche control on any given morning. "On big control days, I might be on the mountain by quarter after five to see what happened overnight and check current conditions and the forecast," Jan told me. "Some people will come up around quarter to six to prepare charges and the rest (of the people on patrol) by quarter to seven." At that point, assignments will be handed out and work teams comprising most of patrol will be dispatched to avalanche control assignments. These may consist of ski-cutting cornices, setting hand charges, starting slides below fixed bomb trams, firing avalanchers or dropping explosives from a helicopter. Control on Whistler is divided into three zones. "We can’t open the mountain until Zone A is complete," Anton explained. Zone A includes Lower Insanity, Goat’s Gully, Redline, and Upper Franz’s cliffs, among other features. As little as 3 centimetres of snow accompanied with the right wind can mean control work in Zone A. Once it’s finished, the lower mountain can open. But of course, it’s the upper mountain the powder hounds want to ski. "Zone B includes Back Bowl, the Waterfall, Harmony Bowl, KC Ridge, Harvey’s Harrow, Glacier Bowl, and Surprise. Once we do B, we can open Harmony Express," Anton said. The rest of the work, Zone C, controls Whistler, West, and Sun Bowls, Southside and Piccolo. When it’s complete, visibility and weather permitting, the Peak Chair can open and everybody’s happy. On an average control day, full control can mean igniting anywhere from 100 to 150 kilos of explosives. That number can rise to 200+ kilos on a big control day. Meanwhile, across Singing Pass, Tony Sittlinger or Bruce Kay are calling the shots on Blackcomb. As on Whistler, Blackcomb’s forecasters track first hand data from various places on the mountain as well as other sources and compile a picture of the ever-changing snow pack. On a control day, they’ll head up the mountain by snowmobile at 6 a.m. or earlier to check the overnight weather and forecast, factor it into their stability evaluation and make their decisions on the day’s avalanche control. "Because of its aspect, we can generally get a lot of the mountain opened pretty quickly," Tony said. Control along the Cafe Wall, behind Rendezvous dropping off into Jersey Bowl, is often all that’s needed to make the runs off Solar Coaster safe for the public. "Next, we’ll do Chainsaw Ridge (the ridge running to the left from the top of Jersey Chair). After it’s controlled, we can open Jersey," he explained. After controlling further up Chainsaw Ridge, the south side of 7th Heaven can be opened. Often, at the same time, control work is being done around Crystal Ridge to enable Crystal Chair to open. From the top of 7th Heaven, following the ridge along toward Blackcomb Peak, Northside is blown and once its eight or so avalanche routes are stable, "that opens up Horstman and the rest of 7th," Tony said. This leaves only Blackcomb Glacier — an area larger than many ski resorts — to be stabilized before the remainder of the mountain can be opened. On a sizable day, the crew of eight can blow through 80 to 120 kilograms of explosives. But making the ski areas safe is only a part of the avalanche puzzle and ironically, is part of both the solution and the problem. By making the high alpine so accessible and by making skiers feel safe to the point of oblivious within patrolled and controlled acreage, the more adventurous among us are given a greater opportunity to go, unprepared, into the backcountry. "I see it all the time," Tony said. "Guys with no equipment and no clue following tracks out of bounds. If you don’t know, don’t go." And if you do go, be prepared. The absolute minimum you should take into the backcountry is another person. Solo travel is foolhardy. The best equipment won’t help you get yourself out of an avalanche; only the people travelling with you will do that. Basic backcountry equipment includes maps and compass and the knowledge to use them but, more importantly, includes a shovel, avalanche probe and transceiver. Buying and carrying the equipment isn’t enough; you have to know how to use it and use it quickly and efficiently. Ski patrol on both mountains always wear transceivers and frequently practise their use. The goal is to find a buried beacon in the area within two minutes. Time is everything: if you survive the slide, you’ve got a 50 per cent chance of living to tell the tale if you’re found within 30 minutes. After that, the odds drop quickly. Without straying too far from home, there are lots of resources to draw on to increase understanding about avalanches. Both mountains offer basic, consciousness-raising tours. Blackcomb runs Avalanche Awareness Tours daily, Whistler whenever several people have signed up. Blackcomb’s program is overseen by Richard Wyne. On a day’s tour with guide Rob Bau, we observed natural avalanche routes at various places on the mountain, dug a snow pit to determine and examine the distinct layers, tested their cohesiveness and stability and searched for hidden transceivers. The tour doesn’t pretend to be an avalanche course, only an eye-opener. Multi-day courses are offered several times throughout the year by the Canadian Avalanche Association. These are full-on, detailed courses leading to successively higher levels of professional certification. And any quest for knowledge and understanding should start at the library. Locally, the library has two titles offering a good launch point for anyone interested in avalanche safety: The Avalanche Handbook by David McClung and Peter Schaerer, and Avalanche Safety for Skiers and Climbers by Tony Daffern. As both books I’m sure warn you, books are no substitute for experience and knowledge of local conditions. For up to date knowledge of local conditions, call or stop by either mountain’s ski patrol. The information you’ll receive in a five minute chat with patrol will be sound, in-depth and could save your life.



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