Glaciation

Key words:

Glaciation = The action of glaciers forming, moving, etc.

Ablation = The action of melting.

Plastic flow = The flow of the lower, airless ice of a glacier, which is flexible due to meltwater beneath acting as lubricant as well as gravity.

Brittle flow = The flow of the higher, oxygenated ice of a glacier, which is prone to splitting due to not being fully compressed.

Firn = The ice of a glacier that is in the state between complete compression, still containing air gaps, forming closely-spaced crystals of ice.

Alpine = Referring to anything that occurs on a mountain/mountainside

Ice sheet = A type of glacier that covers large areas of low-altitude land during periods of low temperature, spreading outwards from the centre as it flows.

Glaciology = The status of a glacier and its effect on the landscape.

Ice sheets VS Alpine glaciers

Ice sheets/Continental glaciers

• Ice sheets are large expanses of ice that cover land like a blanket.

• They are formed in places of low temperature or during periods of low temperature only (ice ages).

• Ice sheets are extremely thick, averaging at 2 kilometres, and to qualify as an ice sheet, they must cover at least 50,000 square kilometres.

• Ice sheets spread out from the centre of their dome shape due to difference in temperature between areas, gravity, etc.

• Known ice sheets in the world include Antarctica and the North Pole.

Alpine glaciers

• Alpine glaciers are glaciers that form at high altitudes on mountains. They are more common than ice sheets.

• They are formed at high altitudes, where snowfall occurs almost daily, and they flow downhill due to gravity.

• Alpine glaciers are usually smaller than ice sheets.

• Known alpine glaciers are found in the Alps, Andes, and mountainous regions like Chile.