Glaciers are present on the Earth in the form of ice sheets in the polar regions which are known as continental glaciers but that does not mean glaciers are only present in the polar regions. They are found in all other parts of the world except the continent of Australia. These are great sources of fresh water on earth that are present in the form of dense ice. In this article, we will be talking about this landform. In this, we will learn about the meaning or definition of the glacier, their distribution, benefits, and other related concepts. This article will help you to understand the very important landform of the Earth and helps you in your studies.
Glacier Meaning and Definition
It is a body of dense ice that moves slowly. It is a perennial structure that forms because of the accumulation of recrystallization of ice, snow, rock, sediments, or any other form which originates on land. They exist where the average annual temperature is closer to the freezing point and precipitation in winters have to snow and especially exist in those areas where temperatures of the current year do not affect the snow accumulation of the last whole year. This continuous accumulation of ice leads to the formation of glaciers. These glaciers look like mountains or peaks and also termed sometimes as mount glacier or glacier mountain.
Mendenhall Glacier in Alaska is a type of mountain glacier as well as a temperate glacier which also consists of a glacial lake and glacial caves. Glacier ridge can be seen in various mountain ranges as well.
According to the Oxford Learner Dictionary, “ glacier means a large mass of ice, formed by snow on mountains, that moves very slowly down a valley.”
According to the Cambridge Dictionary, “ glacier means a large mass of ice that moves slowly.”
Types of Glacier
Glaciers can be majorly divided into two classifications based on geographic locations such as
The glacier mountain finds in the tropical regions are known as tropical glaciers. For example, glaciers present in India and Pakistan which are tropical countries.
The glacier mountain or range or sheets present in the temperate regions are known as temperate glaciers. For example, the Fox glacier in Newzealand or Mendenhall glacier in Alaska are considered temperate glaciers.
Other Types of Glacier Mountain are Classified as Under:
These are massive thick glaciers that covered most of the planet during the ice age. They are present on the gentle terrain and sometimes they are so thick that they cover the underlying features as well. From a central accumulation zone, these sheets move in all directions outwards. For example, the Antarctic ice sheets.
The floating parts of ice sheets are known as ice shelves. For example, there are a lot of such ice shelves in Greenland and Ellesmere Island.
These are restricted to mountain plateaus and are smaller ice sheets. For example, on Baffin Island the presence of the Penny Ice Cap.
These are formed inside or near the mountains in a bowl-like depression. Mostly due to avalanches, the ice or snow accumulation occurs here from the surrounding slopes. For example, Lower Curtis glacier in Washington.
They are formed on the walls of the glacial valley and found in the regions where there are steep mountains. For example, in the Alps mountains, they are common.
These are the glacier rock that finds their ways to reach the oceans and are insensitive to climate change.
Distribution
They are found on all the continents of the earth except Australia. The distribution in different continents and regions of the world is mentioned below in the table:
Regions |
Percentage |
Antarctica |
91% |
Greenland |
8% |
North America |
>0.5% |
Asia |
0.2% |
South America, Arica, Europe, and others |
>0.1% |
Climate
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The climate and temperature of the glaciers vary with locations and time.
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Somewhere the entire region is under the melting point and sometimes it is only under the melting point in the sole.
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In some regions, it can have a combination of both such as the base layer is at the melting point but the upper layer is below the melting point.
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The temperature of 0 degrees celsius can be seen in the temperate glaciers.
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The temperature of -40 degrees celsius to -60 degrees celsius can be seen in the upper layers of the Antarctic region.
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If the temperature reaches up to the pressure melting point, it can lead to glacier erosion.
Vegetation and Wildlife
These regions do have harsh conditions but still provide some favourable conditions for various species.
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Animals found here such as bear, snow leopard, wolverine, etc.
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Vegetation like algae, fungus, lichens, mosses, mushrooms, liverworts, etc.
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Tundra and alpine vegetation are found in temperate regions.
Benefits
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They are a great source of fresh water in the form of glacier lake and glacier streams.
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They are useful for the production of hydroelectric power.
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Glacier peak or mount glacier also serve as tourist attractions and a source of great revenue for the state.
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They maintain the ecological balance of the planet.
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They maintain global temperature.
Did You Know?
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If the entire glaciers or ice sheets of Antarctica melts then the sea level will almost rise by 65m which means London will be submerged underwater along with several other similar places.
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Antarctica and Greenland combined hold more than 99% of the glaciers of the Earth.
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Glaciers move very slowly. The Kutiah glacier of Pakistan has moved about more than 12km in only 3 months and it is the fastest glacier surge ever recorded.
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Lambert – Fisher Glacier present in Antarctica is one of the largest glaciers in the world.
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Fox glacier which is present in Newzealand is one of the most accessible glaciers and also the most attractive tourist destination with 1000 tourists daily visits.
Conclusion:
Thus, in this article, we have covered one important landform i.e. glacier. We have learned the meaning and definition of glaciers, their various types along with their distribution around the world. We have seen its various benefits and have learned what will happen to Earth if glaciers melt. These are dense and huge mass of ice sheets that move very slowly and are a great source of freshwater and maintains the global temperature of the planet. These notes will help the students of Class 8 as well as the students of higher classes.
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