Glaciers are huge masses if snow and ice that have been compacted over many thousands of years. Their weight is such that when they move they do so very slowly the bottom slowed by the ground. They originate from the 'ice age' (18,000 years ago, covering 1/3 of the earths surface) and as the earth has warmed they have melted and reduced in size. Having said that they still cover 10% of the earth. When the majority of the glaciers melted (after the ice age) they left behind changed landscapes that will be discussed in the next blog. A local example of a glacial landscape is the lake district.
In the high mountains of Britain we can see the effects of glaciers. This is the Buttermere valley in the Lake District. This valley would have been filled by ice. The valley has been straightened and deepened by the erosion. This type of valley is called a U-shaped valley.
The backwall is amazingly steep in Buttermere - there's a road down it (angle is about 29%) which I'm cycled down - nearly killed myself! The ribbon lakes in Buttermere are also classic examples.
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