1.a Glaciated landscape as system Flashcards
what type of system is a glacier?
An open store
inputs of a glacier
- snow and rain
- thermal energy from sun
outputs from a glacier
- Glacial wind and erosion
- evaporation
- sublimation/meltwater
Stores from glaciers
- ice
-water
-debris
Flows within a glacier
- movement of ice, water and gravity down slope due to gravity
What does equilibrium mean within a system?
Where the inputs =outputs
So in a glacier the rate of accumulation = the rate of ablation
What is the glacial mass balance/ glacial budget ?
the difference between inputs and outputs over a year
What is accumulation?
imputs put together
input greater than output
What is ablation?
output greater than input
so MELTING
How is a glacier formed?
1) accumulation of snow
2) lower layers compact through nirvation
3) The ice compacts to firn
4) with further compression air is forced out (sintering)
Eventually forming a glacier
What is the nivation, firn and sintering?
Nirvation - alternating thawing and freezing converts snow to ice
Firn - compressed type of snow
Sintering- process of compressing ice further
Positive feedback loop example
- increase a change
melting of a glacier –> low albedo from sea –> so more ice melt
Negative feedback loop
- reduces a change
Clouds acting as albedo effect causing less ice to melt
What is glacial advance ?
The forward movement of the snout of a glacier. - positive mass balance
what is glacier recession?
The shrinking of the snout of a glacier - negative mass balance
