A glacier is essentially a huge mass of ice resting on land or floating in the sea next to land. Moving extremely slowly, a glacier acts similarly to an immense river of ice, often merging with other glaciers in a stream-like manner.
Regions with continuous snowfall and constant freezing temperatures foster the development of these frozen rivers. It is so cold in these regions that when a snowflake hits the ground it does not melt, but instead combines with other snowflakes to form larger grains of ice. As more and more snow accumulates, mounting weight and pressure squeeze these grains of ice together to form a glacier.
A glacier cannot form unless is it above the snowline, the lowest elevation at which snow can survive year round. Most glaciers form in high mountain regions such as the Himalayas of Southern Asia or the Alps of Western Europe where regular snow and extremely cold temperatures are present. Glaciers are also found in Antarctica, Greenland, Iceland and Canada.
Glaciers may be retreating worldwide due to global warming, but they still cover about 10% of earth’s land and hold about 77% of earth's freshwater.
Types of Glaciers
Alpine Glaciers or otherwise known as mountain/cirque glaciers form on the side and crests of mountains with subtypes such as;
- Valley glaciers are where the glacier takes up the space of an eroded stream or a valley.
- Tidewater glaciers are where glaciers meet the sea. Icebergs are formed when parts of the glacier break off.
Continental Glaciers are bigger then alpine types. They are an expansive, continuous mass of ice.
- Ice sheets are the largest type of glacier. They can extend over 50,000 square kilometres and are only found in Greenland or Antarctica.
- Ice caps are smaller and are a rough circular shape that blanket the landscape.
- Ice fields are the smallest continental glaciers. Tend to be elongated and do not cover the land.
The speed of glaciers can be from rest to over a km per year, but on average move a couple of hundred feet a year.
Glaciers have formed many landscapes and formations we see today by the process of abrasion. Glaciers can pick up rocks as they move and grind, squeeze and erode the land they are moving over. Creating new formations. Many common types of formations are U-shaped valleys, long, oval hills called drumlins and hanging waterfalls. Moraines are also common. These are formed by the deposition of materials from a glacier and appear as linear mounds of mixed rock.
Regions with continuous snowfall and constant freezing temperatures foster the development of these frozen rivers. It is so cold in these regions that when a snowflake hits the ground it does not melt, but instead combines with other snowflakes to form larger grains of ice. As more and more snow accumulates, mounting weight and pressure squeeze these grains of ice together to form a glacier.
A glacier cannot form unless is it above the snowline, the lowest elevation at which snow can survive year round. Most glaciers form in high mountain regions such as the Himalayas of Southern Asia or the Alps of Western Europe where regular snow and extremely cold temperatures are present. Glaciers are also found in Antarctica, Greenland, Iceland and Canada.
Glaciers may be retreating worldwide due to global warming, but they still cover about 10% of earth’s land and hold about 77% of earth's freshwater.
Types of Glaciers
Alpine Glaciers or otherwise known as mountain/cirque glaciers form on the side and crests of mountains with subtypes such as;
- Valley glaciers are where the glacier takes up the space of an eroded stream or a valley.
- Tidewater glaciers are where glaciers meet the sea. Icebergs are formed when parts of the glacier break off.
Continental Glaciers are bigger then alpine types. They are an expansive, continuous mass of ice.
- Ice sheets are the largest type of glacier. They can extend over 50,000 square kilometres and are only found in Greenland or Antarctica.
- Ice caps are smaller and are a rough circular shape that blanket the landscape.
- Ice fields are the smallest continental glaciers. Tend to be elongated and do not cover the land.
The speed of glaciers can be from rest to over a km per year, but on average move a couple of hundred feet a year.
Glaciers have formed many landscapes and formations we see today by the process of abrasion. Glaciers can pick up rocks as they move and grind, squeeze and erode the land they are moving over. Creating new formations. Many common types of formations are U-shaped valleys, long, oval hills called drumlins and hanging waterfalls. Moraines are also common. These are formed by the deposition of materials from a glacier and appear as linear mounds of mixed rock.
Perito Moreno Glacier, Argentina
Moraine above Lake Louise, Canada
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