With the gaining popularity of freeskiing in the backcountry, it is important to educate yourself on avalanche safety. Avalanches can be disasterous but with proper training and precautions risks are greatly reduced. This article will provide you basic information to make you aware of the danager an avalanche poses, help you identify their warning signs and take steps to minimize your risk. SkiEnthusiast.com also strongly encourages you to take an avalanche safety course before you venture into the backcountry with friends because reading alone is no substitute to the field experience you get in a class.
To begin it is important to describe what an avalanche is. An avalanche is a slab or cohesive plate of snow that moves as one large unit and can shatter like glass. To imagine this, consider being on a roof, then having the entire roof slide off the house with you and shatter into pieces as it hits the ground completely burying you. This type of avalanche causes the most fatalites. A sluff is a bunch of loose snow falling down the mountain. These avalanches cause very few deaths. To get a feeling for an avalanche, check out some of the raw footage from Teton Gravity Research.
Snow accumulation over the course of a season causes layers to form in the snow. Avalanches are triggered when a weak layer of snow beneath the surface is fractured by a heavier slab (cohesive unit) of snow on the surface or the combined weight of this slab and a skier. The slab then slides on the weaker surface and fractures as it hits obstacles in its path. Since skiers cause concentrated stress on these already fragile layers, avalanches are most often triggered by a skier. It is also possible to trigger slides above you but this is much more rare. Loud sounds will almost never trigger an avalanche unless it is of the magnitude of a large exposion in close proximity of the suspect snow.
Once a skier is caught in an avalanche, it is nearly impossible to out run as they typically reach 60 – 80 mph in only 5 seconds. Wet avalanches travel much slower at 20 mph. Once the avalanche comes to a stop, it quickly sets up like cement. This makes it difficult to dig through and impossible to dig yourself out if trapped beneath the surface. Once buried, you will not be able to move your arms and legs and your only hope for survival is for members of your group to dig you out. Your chance of survival is best in the first 15 minutes at 93% and diminishes quickly to 30% after 35 minutes and is further reduced to 5% after a little more than two hours (Statistics obtained from Avalanche.org). The reason your time is limited under the snow is because your breath freezes the snow around your mouth and you eventually die from carbon dioxide poisoning.
A common misconception about avalanches is that they are not predictable. To the contrary, there are many warning signs to the trained observer. This is why less than 1% of avalanche professionals die in them. There are several factors that contribute to the occurrence of an avalanche including terrain, weather and snowpack. Spotting Avalanche Terrain provides insights into how backcountry guides predict avalanches and to recognize and avoid potentially danagerous situations yourself. It is also strongly recommended that you always hire a guide when traveling in the backcountry unless you have years of experience predicting avalanches yourself. The athletes in the movies always use backcountry guides, despite their own knowledge and skill, to maximize their safety when skiing and filming on extreme terrain. In addition, they practice avalanche safety drills on a regular basis. Since these are the most talented and accomplished skiers on the mountain, we at skienthusiast.com believe it wisest to follow their lead.
Tips to Survive provides practical information on how to plan your trip, maximize safety and to survive an avalanche in the unfortunate event you are ever in one. It is also recommended that you visit the recommended links because they provide detailed information from avalanche experts, questions and answers, forecasts and fantastic illustrations.
It is important that we don’t let the fear of an avalanche stop us from skiing the backcountry terrain we love. It can be skied safely when we increase our understanding of the danagers, learn to recognize the warning signs and take the necessary precautions to mitigate risk.
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