What is a glacier?
A glacier is a large body of ice and snow. They are the largest source of freshwater on Earth. The water you drink could have once been inside a glacier!
Around 10% of land on Earth is covered by glaciers. Most glaciers are located near the North and South Pole in places like Alaska, Greenland and Antarctica.
Scientists who study glaciers are called glaciologists.
How do glaciers form?
Glaciers form when snow builds up faster than it can melt. When snow keeps building up, it becomes heavier and heavier. Eventually, it turns into ice.
It can take hundreds of years for this to happen. The Antarctic is a giant glacier that has been forming for over 40 million years!
What are glaciers made of?
Glaciers aren’t just snow and ice. They contain water, rocks and sediment. This can make the ice look very dirty sometimes.
Do glaciers move?
Glaciers may look like they’re sitting still but they actually move very slowly.
Glaciers move because all the weight from the ice and snow causes them to deform and flow. The bottom of glaciers are more watery from the melted ice, this helps the glaciers slowly move downhill.
Glaciers move from higher ground to lower ground and can flow all the way down to the sea!
An interesting fact about glaciers is that the top of the glacier moves faster than the bottom, this is because of friction.
Did you know?
-
When glaciers move much faster than normal it is called a glacial ‘surge’.
-
Glacier ice stores approximately 75% of the Earth's entire freshwater supply.
-
Glaciers can also be found near the equator in high mountains like Mt. Kilimanjaro in Africa.
-
The world’s largest glacier is the Lambert-Fisher Glacier in Antarctica. It is 100km wide and 400km long.
-
Alaska has more than 100,000 glaciers.
