glacier systems Flashcards
inputs
1) snow (from precipitation or avalaches)
2) condensation of water vapur from the air which then freezes
3) deposistion of water vapur from the air. (where vapour turns directly into ice crystals without passing through the liquit stage)
4) bits of rock collected when the glacier carves away at the landscape
stores
1) the main store is ice in the glacier itself
2) meltwater is stored on and within the glacier
3) rock is also stored in or on the glaceirs
flows
1) meltwater flows through glaciers to channel storage at the base of glaciers
2) debris flow through glaciers
outputs
1) ice can melt and flow out of the glacier as meltwater
2) surface snow can melt and evapourate
3) snow can be blown away by strong winds
4) with glaciers that end at see or a lake, blocks of ice fall from the snout (the front) into the water to create iceburgs
what is the
glacial mass balance relationship
the glacial mass balane is the relationship between a glaciers inputs and outputs
where is there more accumulation
there is more accumulation than ablation in the upper part of a glacier
zone of accumulation
where is there more ablation
there is more ablation than accumulation un the lower part of the glacier
zone of ablation
where is the glacier at equilibrium
the glaciers equilibrium point is where the accumulation and ablation is equal
middle of glacier
positive regime/mass balance
if there is more accumulation than ablation over a year, the glacier has a positive regime/mass balance
negative regime/mass balance
when there is less ablation ovrr a year and the glacier shrimks and retreats
negativie feedback mechanisms
negative feedback mechanisms minimise the impact an input oe output has by counteracting it.
eg if the sice of the ice input increases, a glaciers movement may speed ip so that more meltwater and ice are output as its snout ans=d the mass of the glacier remains constant
positive feedback
the resonse to a change makes the change even greater
