What Is The Reason That The Glaciers Still Exist?
A continental glacier is the great mass of ice, which gave rise to the Ice Age in North America. The thickness of this glacier may be well about 455 meters at its’s center. This great glacier probably formed and melted away at least four times during the Ice Age.
The Ice Age or the glacial period that took hold in other parts of the world has not yet had a chance to melt away. Greenland island is still covered with continental glaciers. There is a very small exception to it at its fringe around its edge. At the peak, this glacier attains about 300 meters in height. Antarctica is also a vast continental glacier with a height of 3,000 metres to 4,000 metres at places. These glaciers still exist, for the reason that they have not had the occasion, to melt since the Ice Age. Most of the present Glaciers are very recent formations and are valley type.
It starts in a broad, steep-walled valley shaped like a great amphitheater. The snow is blown into this area, or slides in from avalanches from the upper slopes. The snow does not melt even in summer and continues to pile up year after year. Eventually, the pressure from above increases, coupled with some melting and freezing. It forces the air out of the lower mass and thus changes it into solid ice. The increased pressure from the weight of snow and ice squeezes this mass of ice until it begins to creep, down into the valley. This moving tongue of ice is the valley glacier.
There are more than 1200 such glaciers in the Alps of Europe. Glaciers are also existing in the Pyrenees, Carpathian, and Caucasus Mountains of Europe and in southern Asia. In southern Alaska, there are ten of thousands of such glaciers. There are some with their length extending up to 40 and 80 kilometers.