Glaciers

The word "glacier" comes from a French word which is derived from the Latin word "glacies" meaning "ice".

 

Where do glaciers form?

An area where a glacier has formed is called a "névé". It is usually between mountains where snow can easily store and compact.

Mountain valleys are normally "V" shaped but glaciers widen and deepen the valleys into a "U" shape. The depressions left behind then fill with water to create lakes and fjords.

 

Icy words 

Glacier calving: when a chunk of ice breaks off the edge of a glacier.


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Iceberg: when a chunk of broken ice floats in the water.

Bergy bits: a small iceberg.

Till: a mixture of rock, sand and mud which is carried by a glacier and gets left behind when the glacier melts.



Why are glaciers sometimes blue?

Have you ever noticed that some glaciers look blue? Most snow and ice is white or clear so what makes some glaciers blue? 


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It all has to do with weight. The weight of a glacier makes snow and ice pack together tightly. Over time, the snow becomes very dense and forces out air bubbles. This changes the structure of the ice crystals causing the dense ice to absorb red light and reflect blue light. The result is a blue glacier!



Types of glaciers

There are two main types of glaciers:

Alpine glaciers (also called mountain glaciers): these glaciers form high up in the mountains and flow downward through valleys.


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Continental glaciers: these glaciers are spread out over a large area of land. They are much bigger than Alpine glaciers. Most continental glaciers were created a long time ago, during the Ice Ages. They often flow towards the sea and break up. Continental glaciers are found in Greenland and Antarctica.

 

 

Did you know?

  • Glaciers can be found in mountain ranges on every continent except Australia. 
  • Animals like polar bears, seals and walruses use icebergs as a place to rest and hunt for food.
  • The Titanic sunk because it hit a huge iceberg.
  • If the Antarctic ice sheet would completely melt, sea levels would rise 65m and cities like London would be lost underwater. 
  • Glacial ice can be thousands of years old. By taking out the ice and studying it, scientists can find out what the climate was like on Earth thousands of years ago.