It is important to note that glaciers are classified based on two factors: size and topography. Due to this, they are broadly classified into two groups: alpine glaciers and ice sheets. Firstly, we will look at alpine glaciers.
Alpine glaciers classifies those which are formed on mountains and can be found in the world's highest mountains and are found on most continents (although there are none in Australia, alpine glaciers can be found in New Zealand). Due to this, they are often known as mountain glaciers.
Valley glaciers are those which have commonly originated from mountain glaciers. They begin to move down into valleys and can be very long, some often exceeding the snow line and may even reach sea level.
Hanging Glaciers are so called due to the fact that they cling to the side of steep mountains. They usually form at the top of a mountain or valley but doesn't descend into the main glacier or valley below. Instead, the ice often calves in avalanches to the glacier or valley below (making them often extremely hazardous).
Piedmont glaciers are found when valley glaciers flow from a relatively narrow valley into a much wider valley or plain. Due to this, they then spread out into large, bulb like features. The largest Piedmont glacier in the world is found in Alaska: the Malaspina glacier. It spreads over 5,000 square kilometres and can be seen in the picture below:
Cirque glaciers are named after the bowl shaped hollows that they occupy which are known as cirques. They are most usually found high up on the side of mountains and are most often wider than they are long.
Tidewater glaciers are valley glaciers which have flown far enough that they reach the sea. The leading edge of the glacier lifts up and floats in the water which thus forms cliffs of ice. Huge chunks of ice may break off at the edge of the glacier, a process known as calving.
The last type of glacier that we will look at will be ice sheets. These can only be found in Antarctica and Greenland and are not restricted to mountainous areas; instead they spread out in all directions from the center and cover vast areas. The largest of ice sheets are known as continental glaciers.
This blog post has looked at the different type of glaciers that can be found and has identified each type with a photograph. When teaching this section, I think it would be important to illustrate each glacier with a picture as it is often easier to remember and learn about them with a visual aid. It is a brief section which could be taught in the form of a simple game, matching pictures and definitions, as was done for the key vocabulary table in a previous blog post. This would help to make the lesson a bit more fun for students and would help to further engage them with the topic.
I just want to round this blog post off with a good video I found on the BBC website showing a glacier in action (definitely helped by the fact that Sir David Attenborough is the narrator!): Glaciation In Action - Frozen Planet
Links used:
http://nsidc.org/cryosphere/glaciers/questions/types.html - National Snow and Ice Data Centre
http://iceland.vefur.is/iceland_nature/glaciers_in_iceland/ - Icelandic Glaciers
http://education.nationalgeographic.com/education/encyclopedia/glacier/?ar_a=1 - National Geographic
http://www.swisseduc.ch/glaciers/glossary/ice-sheet-en.html - Glaciers Online
http://www.unep.or.jp/ietc/publications/short_series/lakereservoirs-2/4.asp - UNEP
Great post, and really good images to go with the descriptions. This is the type of post you could create to use as extra homework support.
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