Types of glaciers:
Where do valley glaciers exist?
Ice shelves are thickest on:
their landward side and thinning seaward
Ice sheets exist:
on a larger scale than valley glaciers
Ice caps bury what?
Outlet glaciers have 'tongues' of what?
ice flowing outward from larger ice masses and into the sea
Piedmont glaciers occur where?
valley glaciers exit a mountain range onto broad lowlands
If the ice on the earth melted, what would the sea level rise to?
60 to 70 meters
High latitudes and high altitudes can form:
elevation above which snow remains throughout the year
Elevation varies with:
Steps in the formation of glacial ice:
•Air infiltrates snow
•Snowflakes become smaller, thicker, and more spherical
•Air is forced out
•Snow is recrystallized into a much denser mass of small grains called firn
•Once the thickness of the ice and snow exceeds 50 meters, firn fuses into a solid mass of interlocking ice crystals – glacial ice
Two basic types of glacial ice movement:
Plastic flow occur where?
within the ice
Basal slip is:
Entire ice mass slipping along the ground
Tension causes what?
crevasses to form in brittle ice
Zone of fracture in:
the uppermost 50 meters
Some glaciers exhibit extremely rapid movements called
Budget of a glacier:
Balance between ice accumulation at the upper end of the glacier and loss at the lower end
Zone of accumulation:
the area where a glacier forms
Zone of wastage:
the area where there is a net loss of ice due to melting and calving
the breaking off of large pieces of ice
What happens if accumulation exceeds ablation?
the glacial front advances
What happens if ablation increases and/or accumulation decreases?
the ice front will retreat