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Avalanche-formation
Avalanches can be caused by different factors. Here it mainly depends on the type of avalanche, e.g. wet snow avalanches, snow slabs, etc.. The risk assessment also differs considerably here.
Formation of snow slabs:The formation of slabs of snow is most likely on a slope of 25° to 45°, with steeper slopes generally also promoting the descent of slabs of snow. An important factor for the fall of snow slabs is the ground cover, so the probability of a fall on bare slopes is higher than on overgrown ones. This is because the friction of the ground cover is lower there and larger snow slabs can form, but this only applies if the vegetation protrudes from the snow cover and is dense enough. However, there is a catch here, certain types of vegetation can even promote the departure of snow slabs because they promote cavities in the snow cover. The hillside location plays a further role in the formation of slabs of snow.
The risk of avalanches increases significantly with fresh snow, because fresh snow is looser and slides more easily than older snow. Because fresh snow isn`t really firm yet, it can easily be transported by the wind. This transported snow (drift snow) is deposited on the slopes and remains in the slipstream. There, the snowdrift then forms snowdrifts or snowdrifts. The snowdrift can be under very high tension, so that the smallest external interference could lead to an avalanche. Snowdrift is not easy to spot as it can be both hard and soft. Even when it snows on it again, the snowdrift retains its hazard potential.
The amount of snow also plays a crucial role. If a lot of snow accumulates in a short time, the additional weight increases the load on the snow cover. Settling and consolidation cannot proceed so quickly to hold the weight of the fresh snow, the pressure on the lower layers of snow becomes so great that it does can no longer hold the load. Here, the additional weight of a skier is enough to trigger an avalanche. Wet snow and drift snow are particularly unstable.
The temperature is another risk factor, the colder the temperatures are, the longer it takes for fresh snow to solidify. But higher temperatures are also dangerous, because rising temperatures increase the amount of meltwater and the snow cover becomes unstable. Basically, every change in temperature results in a change in the risk of avalanches.
