So, okay getting your nails done has nothing to do with Glaciers BUT today whilst getting my graduation nails touched up at a local beauty salon, i over heard the owner talking about her holiday where she was skiing in the glaciers! Just proves more people are aware of them than we think!
What is a Glacier?
Aim: To be able to define different types of glacier.
Firstly take a look at this video which provides a fairly simple introduction to Glaciers. Feeling clever? Try and answer the two questions at the end!
So as already identified a glacier is: A mass of snow and ice which, if it accumulates to sufficient thickness, deforms under its own weight and flows moving slowly down a valley.
But there are many different types of glacier:
TEMPERATE (ALPINE): release huge amounts of meltwater in summer, which reduces friction by aiding lubrication of the ice. Move by basal flow, extending/compressing flow, creep and surges. More likely to erode, transport and deposit material.
POLAR: Occur in regions permanently below 0°C where no melting occurs. Therefore movement is slower and move by Internal Flow. Less erosion, transportation and deposition occurs.
And yet to make things even more complicated there are yet more varieties of glaciers:
ICE SHEET/ICE CAP: This is where the ice builds up as a dome over the underlying topography. These domes are normally drained by outlet glaciers. Very dense and found in Greenland and Antarctica.
Figure 1: Image showing an Ice Sheet. (Reference: SPRI)
ICE SHELF: This is where the ice forms a floating sheet in a topographic embayment (a gap in the coastline) and flows towards the open sea where it floats. These are the parts that break off, once weakened and cause ice bergs. These can reach up to 1000 m. Anyone remember the titanic?
Figure 2: Image showing Titanic (Reference: UlsterPrints)
MOUNTAIN GLACIERS: These are constrained by the underlying topography of the mountains and form a wide variety of types including a valley glacier, cirque and piedmont.
IN PRACTICE: Students would be asked to go research an example/case study in groups with each group being assigned a different type of glacier and present them back to the class. This will enable them to remember their own examples more readily if they have done the ground work to research them. It’s all about self learning!
References:
Goudie, A (Ed) (1995) The Encyclopedic Dictionary of Physical Geography. 2nd Edition. Blackwell, Oxford.
Redfern, D & Skinner, M (2005) Advanced Geography. 2nd Edition. Philip Allan Updates, Oxfordshire.
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