what is a glacier Flashcards
glaciers can be viewed as systems
What is a glacier?
A long shaped mass of ice moving down a valley due to gravity
Where can cold environments be found? (3)
1) high latitude areas (arctic/antartic)
2) high altitude areas (alpine regions)
3) polar environments (greenland)
what is an ice age?
The periods when there were major cold phases known as glacials and ice sheets covered large areas of the world.
What is a glacial and interglacial period?
Inter glacial period - a geological interval of warmer global average temperatures (glaciers receed)
Glacial period - An interval of time within an ice age that is marked by colder temperatures and glacial movements.
What’s a periglacial area (tundra)?
exist in dry and high latitudes
What are alpine regions?
areas that may contain small ice caps, mountain glaciers and tundra environments
Why is it so cold in polar regions? (3)
1) Less direct sunlight
2) curvature of the earth
3) Albedo effect
How does less direct sunlight make polar regions cold?
less solar radiation is absorbed due to it arriving at a shallower angle–> cases through more atmosphere –> where it looses energy
How does the curvature of the earth make polar regions cold?
incoming energy is spread over wide areas
How does the Albedo effect make polar regions cold?
the snow and ice reflect the received solar energy out
Name characteristics of the polar environment
location/variation/vegetation
L- high latitudes
SV- constant throughout not above 0 degrees
V - little vegetation
Name characteristics of the Alpine environment
location/variation/vegetation
L - High altitudes /mountainous
SV- Summer 4-5 degrees / winter -0
V - limited biodiversity (low lying shrubs
Name characteristics of the tundra environment
location/variation/vegetation
L- between polar and northern forests
SV- below 0 for 6-10 months
more variation the further south
V- limited biodiversity (stunted shrubs)
When was the last glacial maximum?
Occurred 20,000 years ago
The last glacial maximum stats then VS now
Then
8% total earth surface
25%total land surface
33% of Alaska
Now
3% total earth surface
11%total land surface
5% of Alaska