glaciers Flashcards
Things that impact the development of glaciers
altitude, latitude, solar radiation, precipitation
glacier accumulation occurs through
Avalanches, snow fall, superimposed ice wind blow
where has lack of snow fall
east antarctic ice sheet relies on wind blow heavily to move snow mass around the place
glacier systems
inputs = accumulation
throughputs = ice movements
outputs = ablation
examples of ablation
calving large chunks of the glacier come off influence due to rising sea temps
ice within the ocean
whats occurring in Martine glaciers
new Zealand alps high accumulation an ablation
continental high artic glaciers - low accumulation and low ablation
what is the equbrlium line
the line where the snow covered glacier turns to ice
allows to track the movement of the glacier shrinking and expanding
impacts of glacier loss
Human impacts loss of tourism industry
ski industry economic displacement of countries
increased surface run off
4 glacier flow movements
creep fracture basal sliding bed deformation
creep
when old snow compresses an turns to ice all the ice particles align this presure increases they disaglin and this creates downwards movement of the glacier
fracture
the pressure of the snow fall increases so much that the glacier fractures and produces crevasses - often happens on top of brittle glacier
basal sliding and bed deformation
this requires water at the bed rock interface the glacier moves over the saturated sediment and the sediment becomes deformed
abrasion
requires thick ice
and thick rock debris
produces fine grained sediment
leaves stations upon the rock surfaces
plucking
needs thinner ice
requires fluctuating water pressures at the bed rock
produces large rocks and boulders
glacier movement impacted melting freezing
glacier melts moving upwards upon an obstacle and freezes moving downwards
this refreezing aids melting
