The huge amount of snow deposited each year on BC interior mountains is great for winter recreation. World renowned waist high powder and the thrill of travelling to remote parts of the province attract thousands of back country skiers and snowmobilers each year. The high elevation snow is only a short trip away by helicopter or via the newer high tech snowmobiles.
The pursuit of the ultimate adventure does come with some risks though. Avalanches are always a threat especially when the snow is unstable and the slightest disturbance is enough to trigger a slide. In the majority of cases, in fact over 80 percent of the time, people caught in avalanches survive.
Unfortunately some slides are so massive, there is no escape. An average of fourteen people each year are killed by slides in Canada, mostly in southern BC, in a triangle running from Vancouver Island to Pincher Creek to Hinton Alberta.
A typical weather pattern that causes a high risk for avalanches starts with cold temperatures producing a slippery hoar frost layer on the snow. Then when a flood of warm moist air brings a period of heavy snow, the weight of the top layer can easily slide on the icy surface below.
The winter of 2008-09 has seen several of these cold to warm cycles making the snow very unstable. The snowpack has many buried hoar frost surfaces with snow layers sandwiched between.
Twenty-three deaths have been reported in BC this winter, eighteen of them were riding snowmobiles. The total for snowmobilers is much higher than the previous mark of nine deaths in 2002-03. The most tragic accident occurred at the end of December 2008 when several avalanches buried a large group of sledders near Fernie. Eight men, all from the nearby town of Sparwood lost their lives.
The Canadian Avalanche Centre, based in Revelstoke is a not-for-profit corporation that serves as a national public avalanche safety organization. Avalanche forecasts are issued throughout the winter season to alert recreationists to the danger level and threat of avalanches. This year there have been periods of high to extreme danger predicted that keep most people out of harm’s way.
Unfortunately many of the incidents have occurred at a lower danger level, between moderate and considerable, when more people venture into the backcountry. The extremely variable and unstable conditions this year make avalanche prediction very difficult and a high level of training and experience is necessary to stay safe. Training courses put on by the Canadian Avalanche Centre provide skiers and sledders with the necessary tools to assess the danger.
As the spring progresses and the snow levels rise to higher elevations, the danger of avalanches will gradually ease. However, even in summer the higher glaciers can still be unstable especially in the afternoons when melting occurs. It is still a good idea to check the Avalanche Centre web site for latest conditions in the mountains and also have a look at the current weather forecast issued for the area.
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