By skiing off-piste you are to a great extent challenging yourself. However, you are also challenging nature as snowdrifts are not always stable and can become avalanches in a matter of a second.
Avalanches in the mountains are a natural phenomenon. Every year over 100,000 avalanches occur in the European Alps alone. Most of them are spontaneous avalanches triggered by changes in the weather conditions. Skiers or groups of skiers trigger only a few, but some avalanches unfortunately cause fatalities. The victims are often the very skiers, snowboarders, or kickers that have moved onto unpatrolled areas and have caused the avalanche.
The average skier is becoming better and better but also faces greater challenges than before. The growing number of good skiers combined with large groups of snowboarders also seeking virgin powder snow, contribute to the increasing number of accidents in the mountains.
If you keep to the marked trails, there is not too much to worry about. The alpine countries have some of the world's best snow - and avalanche experts who cooperate with the local authorities in order to secure the marked ski trails. In Europe and North America the authorities at ski areas dynamite potential avalanche areas before skiers are let loose on the mountain.
Never leave the groomed and controlled ski trails if:
Avalanches have, and probably always will be, a mystery. There are many reasons contributing to the start of an avalanche - wind, sun, frost, and the curvature of the mountain are some. An avalanche can reach speeds of up to 200 km (120 miles) per hour. Roughly speaking, there are four different types of avalanche.
Loose snow avalanches start at a certain point and thereafter spread in the form of a cone. It takes only instability at a small area to trigger large loose snow avalanches.
Powder snow avalanches, also called "airborne avalanches", seldom occur in Europe. They require especially dry snow that is more common in North America. These avalanches can resemble explosions and often occur after new snow has fallen. Powder snow avalanches rush down the mountain on a pillow of air. The blast is so powerful that it can easily crush houses and cars.
Slab avalanches start when a huge sheet of snow tears free and slides down the mountain. The instability that leads to the avalanche itself has often been caused by excessive winds.
Wet snow avalanches resemble flowing lava, sweeping down the mountain and taking everything with them. Wet snow avalanches are primarily a problem on southerly slopes in the northern hemisphere and during the springtime. The friction in wet snow is quite large making wet snow avalanches considerably slower than dry snow/powder avalanches.
If you ski off-piste, study avalanche warning before you set off. When there is a risk of avalanches, a black and yellow flag will be flown. For insurance purposes, many ski areas fly this flag from the beginning to the end of the skiing season. A better indicator of the risk of avalanches is the international avalanche scale. This is updated daily at every ski resort. Remember, these numbers only give information about the general risk of avalanches; they say nothing about the danger on a specific mountainside.