At the Earth's surface flakes form a blanket of snow. By the end of winter, it reaches more than a meter thick and consists of several layers of snow that formed at different times and under different conditions. Therefore, these layers are not identical. Some of them are dense, others - are loose, some of the fine-grained snow, while others - coarse. Under the action of wind, a thaw, the sun on the snow surface there is pres. Sometimes a firm that maintains a person. At the same time inside is loosening, and on the boundary with the soil formed by the rime of the large hollow crystals. Snow has the same property as the ice. It reflects more than half of the radiant energy of the sun. Especially pure new-fallen dry snow: it reflects up to 90 percent of sunlight. Phenomenon is associated with snow avalanches. Snowpack accumulates on the slopes. And when it accumulates a lot of it by the force of gravity breaks down avalanches. Enormous snow masses reach high speeds and are able to sweep on their way up a mountain slope, even century-old trees, destroying homes and roads, burying everything. Cause of the avalanche is different. It can be heavy snowfalls, strong storms and a sharp drop in air temperature. The reason may be the formation of a thicker snow loose horizon depth hoar, which we described above. In the Alps it is called the snow - quicksand. Especially a lot of avalanches falling from the slopes in the spring. The snow is wet and fragile. By the nature of the motion of snow avalanches are divided into Kosovo, chute and jumping. Most are harmless Kosovo. If they are slipping down the slopes of the snow mass is defined channels. And the most dangerous are jumping avalanche. They meet on the way "trampliny1" which jumped into the valleys. At the same time they acquire a very high speed and produce considerable damage. Often, a sudden avalanche creep, sometimes silently. There are cases that moves ahead of an air wave, which produces even more destruction. Constant avalanches falling leaves deep traces in the mountainous landscape. In areas of frequent avalanches destroyed trees and shrubs, create webs in the forest. Arise, therefore, at the foot of non-forested land in the form of a semicircle. They are called cones avalanches. And the trees get, the oppressed form: they are curved in the form of saber in the direction of the direction of the avalanche. Often avalanches fall in river beds and block them. But after a while the river cuts through a tunnel in the snow dam. A long snow blockage is in the river valley, we finally put only at the end of the summer. To prevent avalanches, a special gornolavinnaya office. In the mountains there are small snegolavinnye station. There are constantly monitoring the snow cover and changes in weather that most often trigger avalanches.
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