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• Glaciers can form distinct landforms through erosion of the landscape such as corries.
• Glaciers also deposit material to form unique landforms such as drumlins.
• Glaciated landscapes are a source of economic activity but also of conflict.

Glaciers are large masses of ice shaped like rivers. They flow like rivers, only much more slowly. As glaciers move, they wear away the land around them through a process called erosion. The eroded material is then transported by the glacier before finally being deposited, or ‘dropped off’.

Glacial landforms are formed as a result of the erosion and deposition process. There are lots of glacial landforms that can be found in the UK, for example in Snowdonia in Wales.

For some glacial landforms, the main process involved is erosion.

Rivers cut V-shaped valleys through the process of erosion. As rivers in their upper course don’t have that much power, they are forced to wind between harder rock leaving ridges of land jutting out. These are called interlocking spurs. Glaciers bulldoze through these valleys making them into distinctive U shapes with flat floors and steep sides called U-shaped valleys, cutting through the interlocking spurs, turning them into truncated spurs.

Once the ice has melted, long narrow lakes known as ribbon lakes can sometimes be formed. They may be created in an area where there is hard rock and softer rock. The hard rock does not get eroded but the softer rock does. Moraine from the melting glacier forms a dam in the valley and water fills up behind.

Corries are bowl-shaped hollows found on the side of a mountain. They form when the glacier deepens an existing hollow through freeze-thaw action and plucking.

As the ice moves down the mountain it does so in a circular motion which further deepens the hollow, leaving a lip at the end. When the ice melts this hollow can fill with water. These are now called corrie lakes or tarns. An example of a corrie lake is Red Tarn in the Lake District.

If corries form back-to-back on a mountain, they wear it away from both sides forming a knife edge called an arête.

If there are three or more corries and arêtes back-to-back, a pyramidal peak can form. This is a sharply pointed mountain peak.

The Matterhorn on the border between Switzerland and Italy is an example of a pyramidal peak.

Glaciers are very powerful and capable of carrying large amounts of rock. Eventually these will be dropped off by the glacier creating distinct landforms.

Deposition happens when material transported by the glacier is deposited and left behind as the glacier melts or moves on.

As the glacier moves down the mountain the air gets warmer. This causes the glacier to begin to melt. At this point everything carried by the glacier is deposited. This material is known as moraine.

There are four types of moraine:

• Terminal moraine is moraine deposited at the end of the glacier.
• If the whole glacier melts, for example as a result of climate change, then all the material is deposited. This is known as ground moraine.
• Lateral moraines are found deposited along the sides of the glacier.
• Medial moraines are found at the junction between two glaciers.

A drumlin is a long oval hill in the shape of a spoon made of glacial deposits. No one is really sure how drumlins form but it is thought it is caused by the ice becoming overloaded with sediment which leads to it being deposited.

Erratics are large rocks or boulders that are often found on their own. These rocks have been transported, sometimes over long distances, before being dropped off.

Glaciated areas have many uses that can provide benefits to the area but can also lead to challenges.

Tourism

The landscapes created by glaciation attract tourists. The mountains provide a place where people can take part in activities such as mountain climbing, hiking and mountain biking and the lakes provide the opportunity for water sports. Sometimes tourism can cause disagreements. Local people are sometimes concerned that tourists cause traffic congestion, littering and damage whilst also pushing up house prices by buying second homes.

Farming

Although the harsh conditions of mountainous areas make most types of farming difficult, sheep farming is a common activity. Although farmland may seem like a natural environment with the green fields, they are in fact man-made. Some people believe that sheep and the clearing of the land for farming should be stopped and the land rewilded.

Forestry

Another common use of land in glaciated areas is for forestry. This is where trees are grown to be used for timber. Coniferous trees are adapted to cope with cold conditions and are perfect for upland areas. Although planting trees is good for the environment, logging companies will often only plant one type of tree leading to limited biodiversity in the area.

Quarrying

Glacial areas often contain large amounts of valuable hard rock. Quarrying takes place to extract rock such as limestone to be used for construction. This causes visual pollution as views are spoilt, noise pollution from the heavy machinery and damages habitats.