Ice Cover And The Pleistocene Epoch Flashcards
What is the cryosphere?
Cold environemtns on our planet where water is in a solid state- ice
What type of ice makes up the cryosphere?
Sea ice
Lake ice
River ice
Snow cover
Ice caps
Glaciers
Permafrost
What is a polar glacier environment
High latitudes of arctic and antarctic
Extremely cold temperatures
Mean annual temperatures -30to-40*c
Low levels of precipitation
What are alpine glacial environments
Found at high altitudes in mountain ranges in mid to low latitude
High levels of precipitation, wide temperatures range and Freeze thaw
Whats an example of an alpine glacial environment
European alps
The Himalayas
What are periglacial environments? (Technical description)
Dont feature glaciers
Found next to glaciers
Features of periglacial areas
Permafrost(permenantly frozen ground)
High altitude and high latitude
Seasonal temperatures vary above and below freezing point
Where can periglacial areas be found? (places)
Extensive in siberia
Alaska
Northen canada
What happens to glacial environments when the glacier retreats
glacial environments are replaced by periglacial environments at the margins of the ice
what is a relict glacial environment
no longer experiences active glacial processes but does display evidence of the Pleistocene glaciation
where is an example of a relict glacial environment
Britain
what are glaciers
large bodies of ice that flow downhill under the influence of gravity
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Slow moving bodies of ice in valleys which shape which the landscape in both polar and alpine environments
what type of area do glaciers form in
temperatures are significantly low to allow snow to persist from year to year enabling a thick layer of snow to accumulate and be slowly compressed forming glacial ice
what are the seven types of ice mass
ice sheet
ice cap
ice field
valley glacier
piedmont glacier
cirque glacier
ice shelf
how large must an ice sheet be
50,000 square kilometres
what two ice sheets are on earth today
Greenland ice sheet
Antarctic ice sheet
what do ice sheets do to the landscape
bury the whole landscape
except the highest mountain summits
what are the uncovered mountain summits on an ice sheet called
nunataks
what are ice bergs
pieces of ice that formed on land and float in an ocean or lake
what is the size range for ice bergs
the term ice berg refers to ice bigger than 5 meters across
what are ice caps
dome shaped masses that covers mountain peaks and plateau areas
what is the size of an ice cap
less than 50,000km*2
what is an example of an ice cap
Vatnajokull in Iceland
what are icefields
very similar to ice caps but are typically smaller
what are the smallest ice masses
niche glaciers
what are niche glaciers
patches of ice in hollows and gullies on north facing mountainside slopes in the northern hemisphere
what are valley glaciers
large rivers of ice contained within steep sided (U shaped) valleys
what do valley glaciers become
move downslope until they reach a flat plain where they spread out into large lobes called PIEDMONT glaciers
what is sea ice
smaller then ice bergs (<5 metres) slushy and shallow
what’s a key factor that leads to the creation of snow
number of positive degree days
What are polar glaciers
Cold based
Frozen to the bedrock
When and where does melting occur on a polar glacier
On the surface in the short summer season
Where can polar glaciers be found
Greenland
Antarctica
What are temperate glaciers
Warm based
Alpine environments
Temperture close to zero
Mild summer causes melting
What is an example of a temperate glacier
The european alps
What is pressure melting point
Temperature at which ice melts at a given pressure
