The glacial period

The Arctic - reign of the polar bear, where he feels itself in its element. The absence of land does not confuse bear, in essence its locality - ice floe of Arctic Ocean. Bears - outstanding swimmers and in search of the food they frequently swim in far to the open sea. Polar bear feeds by fish, it hunts the seal, the seals, the young of walruses. In spite of its power, polar bear needs protection, it is carried into the red of international, and Russian.

Long-standing ice accretions in the high mountain regions and the cold belts of the Earth are called glaciers. All natural ices are united into so-called - part of the hydrosphere, which is found in the solid state. Into it enter ices of cold oceans, and icy caps of mountains, and separated from the glacial panels icebergs icebergs. In the mountains the glaciers are formed from the snow. First, during the recrystallization of the snow as a result of the alternation of meltings and new freezings of water inside the snowy thickness, is formed neve. which then is converted in the glacial under the action of gravitational force ice it is moved in the form icy flows. The basic condition for existence of glaciers - and small and enormous - constant low temperatures during the larger part of the year, with which the accumulation of snow predominates above its melting. Such conditions exist in cold regions of our planet - to Arctic and Antarctic, and also in the high mountain regions.