*Glacial systems

What does the glacial system have?

Inputs, stores and outputs.

There are flows (of energy, ice, water and sediment) between stores.

What is the main input into a glacial system?

Snow (from precipitation or avalanches).

What are the other inputs into a glacial system?

• Condensation of water vapour from the air which then freezes.

• Deposition of water vapour from the air. This is when vapour turns directly to ice crystals, without passing through a liquid stage.

• Bits of rock collected when the glacier carves away at the landscape, and rocks that have fallen from the glacier above.

What is the main store in a glacial system?

The ice in the glacier itself.

What are the other stores in a glacial system?

• Meltwater is stored on and within the glacier, e.g. in supraglacial lakes on top of the glacier.

• Rock is stored on or in glaciers, e.g. debris from freeze-thaw weathering falls onto the surface of glaciers.

What are the flows in glacial systems?

• Meltwater flows through glaciers e.g. from stores in supraglacial lakes to channel storage at the base of glaciers.

• Debris flows through glaciers, e.g. from surface storage to landforms.

How can ice be output from a glacial system?

Ice can melt and flow out of the glacier as meltwater.

How can surface snow be output of a glacial system?

It can melt and evaporate.

How can ice and snow be output of a glacial system?

• Ice and snow can sublimate to water vapour.

• Snow can be blown away by strong winds.

What outputs can occur with glaciers that end at the sea or a lake?

Blocks of ice fall from the front (the snout) of the ice mass into water to create icebergs.