Extreme Environments
Part 1
Global-scale distribution of cold and high altitude environments (polar, glacial areas, periglacial
areas, high mountains in non-polar places) and hot arid environments (hot deserts and semi-arid
areas)
Cold and high altitude environments:
Very uneven distribution
In general, cold environments are found in high latitudes and at high altitudes
Polar environments located near the north and south pole - levels of insolation are very low
Northern hemisphere: belt of periglacial environments
Zone generally not in the southern hemisphere except in small areas, given the relative lack
of land mass
Desert and semi-arid environments:
Cover as much as 1/3 of the Earth's surface
Generally located around the tropics and are associated with permanent high-pressure
systems which limit the potential for rain formation
Four main factors that determine the location of the world's main deserts:
o Location of stable, high pressure conditions at the tropics (Sahara and Australian
Deserts)
o Continentality (distance from the sea) (Sahara, Australia and parts of the south west
USA)
o Rain shadow effects (Patagonia, Gobi)
o Proximity of cold upwelling currents, which limit the amount of moisture held in the
air (west coast of South America (Atacama), west coast of southern Africa (Namib))
Relief and climatic characteristics that make environments extreme, including unreliability and
intensity of rainfall in arid environments and the risk of flash floods
Conditions in extreme environments:
Cold and high-altitude environments:
Varied in their characteristics
Mountain environments: warm days and cold nights. Large amount of rainfall due to relief
rain. However some mountain areas receive small amounts of rainfall because they are in a
rain shadow.
Polar areas generally receive low rainfall- cold deserts
Mountains are difficult to build on and they act as barriers to transport. Soils often thin and
suffer from run off and erosion
Periglacial areas (tundra regions) produce low rates of evaporation, and soils are frequently
waterlogged.
Growing season relatively short as temperatures are above 6 degrees C for only a few
months a year
Some periglacial areas support large numbers of people, and there may be important
settlements adjacent to some high-altitude environments
Desert and semi-arid environments:
In desert areas, the lack of water acts as a major constraint for development.
Part 1
Global-scale distribution of cold and high altitude environments (polar, glacial areas, periglacial
areas, high mountains in non-polar places) and hot arid environments (hot deserts and semi-arid
areas)
Cold and high altitude environments:
Very uneven distribution
In general, cold environments are found in high latitudes and at high altitudes
Polar environments located near the north and south pole - levels of insolation are very low
Northern hemisphere: belt of periglacial environments
Zone generally not in the southern hemisphere except in small areas, given the relative lack
of land mass
Desert and semi-arid environments:
Cover as much as 1/3 of the Earth's surface
Generally located around the tropics and are associated with permanent high-pressure
systems which limit the potential for rain formation
Four main factors that determine the location of the world's main deserts:
o Location of stable, high pressure conditions at the tropics (Sahara and Australian
Deserts)
o Continentality (distance from the sea) (Sahara, Australia and parts of the south west
USA)
o Rain shadow effects (Patagonia, Gobi)
o Proximity of cold upwelling currents, which limit the amount of moisture held in the
air (west coast of South America (Atacama), west coast of southern Africa (Namib))
Relief and climatic characteristics that make environments extreme, including unreliability and
intensity of rainfall in arid environments and the risk of flash floods
Conditions in extreme environments:
Cold and high-altitude environments:
Varied in their characteristics
Mountain environments: warm days and cold nights. Large amount of rainfall due to relief
rain. However some mountain areas receive small amounts of rainfall because they are in a
rain shadow.
Polar areas generally receive low rainfall- cold deserts
Mountains are difficult to build on and they act as barriers to transport. Soils often thin and
suffer from run off and erosion
Periglacial areas (tundra regions) produce low rates of evaporation, and soils are frequently
waterlogged.
Growing season relatively short as temperatures are above 6 degrees C for only a few
months a year
Some periglacial areas support large numbers of people, and there may be important
settlements adjacent to some high-altitude environments
Desert and semi-arid environments:
In desert areas, the lack of water acts as a major constraint for development.
