4.2 The nature and distribution of old environments Flashcards
How long did the Pleistocene era last?
From 1.8 million years ago to about 11,700 years ago.
What was the pattern of temperatures during this era?
An alternating pattern of cold periods (glacials) and warm periods (interglacials)
Where are most of the world’s cold environments?
Far north e.g. Scandinavia
what is the exception for some of the world’s cold environments?
Antarctica and South America
Latitude
east to west
longitude
north to south poles
Altitude
the distance of land from sea level
how many types of cold environments are there?
4
what are the four cold environments?
- Polar
- periglacial (tundra)
- Alpine
- Glacial
Describe the polar environment
- Areas of permanent ice
- essentially the vast ice sheets of Antarctica and Greenland
describe the periglacial environment
- Literally speaking at the edge of permanent ice
- Permanently frozen ground - Permafrost
- where: Northern Canada, Alaska, Russia, Scandinavia
Alpine
- High mountainous areas
- European Alps or New Zealand Alps
- High altitudes = cold conditions (especially in winter)
Glacial
- found in edges of the ice sheets
- particularly in mountainous regions such as the Himalayas and Andes.
what is the soil made up of in cold environments?
- a mixture of weathered rock
- rotted organic matter
- living organisms (biota)
- gases (particularly oxygen) and water
why is weathering limited in cold environments?
- lack of liquid water