What are Glaciers?
A glacier is a large, slow-moving river of ice, formed by many layers of compacted snow. The rate of motion varies greatly, depending on the ambient temperature, depth of the ice, the underlying slope, and other factors. Movement ranges from several meters per hour to several meters per century. Sometimes, when conditions are just right, glaciers experience a surge, accelerating their rate of movement by as much as 100 times. When glaciers surge, they can be a danger to humans, triggering avalanches of rock and snow. Glaciers can be found on every continent and in about 47 countries. Most mountains taller than 4,500 meters (14,800 ft) have them, because temperature tends to quickly drop with altitude. There are two main categories of glacier: alpine glaciers, on mountains, and continental glaciers, on flat land where it is very cold. Continental glaciers almost completely cover Greenland, parts of Iceland, northern Siberia and Canada, and most of Antarctica. About 70% of fresh water on
A Glacier can be simply defined as a large mass of ice that forms on land and shows a slow and significant movement. Glaciers are fallen snow compressed into a large, thick mass of ice over a period of many years. Some glaciers can be as small as football fields while others can be over 100 kilometers long.
