Extreme Environments Flashcards
what are the characteristics of a polar region?
- the high latitudes mean that it is extremely cold, and the further north, the more extreme the cold.
- winters are very cold, up to -50oC with few or no hours of lights
- summers are short with many hours of light; this is the growing season in the tundra
- dry with less that 300 mm of precipitation per year falling mostly as snow
- the coldest glacial regions support no life at all.
what are characteristics of an arid region?
- cold night temperatures because there aren’t many clouds to retain heat
- hot day temperatures, often above 30oC
- occasional intense downfalls of rain can cause flash flooding
- there is very little seasonal change in very arid areas
- not many plant, animal and human life can be supported by the hottest arid environments
- dry - some years may receive less than 250 mm of precipitation.
what variations are there in polar and hot arid regions?
-polar:
glacial = ice-covered - e.g.: Greenland
tundra = frozen soil - e.g.: Alaska
-hot arid:
deserts = less than 250 mm rain per year - e.g.: Sahara
drylands = 250-500 mm rain per year - e.g.: Sahel
how have plants and animals in polar flora and fauna regions adapted?
-glacial regions
>only able to support very little life other than some insects, arachnids and mice.
>some hardy plants grow close to the ground to survive the strong winds.
-tundra regions
>more animals, insects and birds are able to adapt to tundra regions compared to glacial regions. They have adapted to survive the cold with thick layers of fat and/or fur. Many of them are also coloured white to camouflage themselves against the white snow.
>boggy conditions suit water-loving plants such as sedges and moss.
how have plants and animals in hot arid flora and fauna regions adapted?
-semi-arid regions
>the animals found in these regions are able to store water in fat and tend to be nocturnal, spending the day underground out of the Sun.
>insects collect moisture from the air.
>some animals have characteristics which allow them to dissipate heat easily. E.g.: large ears.
>plants store water (acacia trees) and/or have deep roots to reach water which is stored deep underground
>seeds can stay dormant for years, and when they receive rain, they are able to produce brightly coloured flowers to attract insects immediately.
-very arid regions are unlikely to have much plant or animal life
how have humans adapted to the polar environment?
>adaptations to the cold -triple glazing in houses -wear layers, wool, fur etc. to keep warm -use of geothermal power. >adaptation to frozen ground -houses raised up above ground -hunting rather than growing crops. -roads built on gravel to prevent them cracking with solifluction. >adaptations to the snow -steep roofs so snow falls off easily
how have humans adapted to hot arid environments?
> adaptations to the heat
-buildings painted white to reflect the heat
-thick walls and small windows to keep the heat out.
-air conditioning in homes
-wearing loose-fitting clothes.
-wearing head coverings
adaptations to the lack of water
-flat roofs to catch water
-irrigation used to grow crops
-nomadic farming so areas aren’t overgrazed by herds
what are human threats to polar regions? ALASKA
> pollution: oil spills
land degradation: permafrost melting due to buildings heating up land
cultural dilution: loss of native cultures and languages-influence of western culture is growing
out-migration: people are moving away due to lack of social and unemployment opportunities
what are human threats to hot arid regions? SAHEL
> pollution: air pollution from industrialised countries may increase drought
land degradation:desertification leads to disappearing vegetation and soil erosion, due to overgrazing
cultural dilution: traditional rituals performed to entertain tourists
out-migration: people moving away due to a lack of opportunities
what can climate change in polar regions lead to?
- a build up of melt water can cause lakes to burst their banks, resulting in flood water destroying ecosystems
- solifluction - in tundra regions, large areas of soil melt and move like a landslide destroying vegetation in its path.
what can climate change in arid regions lead to?
- extreme drought which the most adapted animals & plants can survive
- desertification - where the area of desert increases
- animals which used to be able to live in what used to be semi-arid areas cannot adapt and unfortunately die.
what are the effects of climate change in polar environments?
>warmer summers -changes in sea ice cover -glacier retreat -permafrost melting -species migration >sea level rises -coastal flooding -erosion -ecosystem changes >all these effects will most likely impact upon humans, also causing... -coastal towns and industry to be threatened -life being more uncertain -people more likely to move away
what are the effects of climate change in arid regions?
> less rainfall
-dryland changes to desert (desertification)
-reduction in grazing for livestock
less reliable rainfall
-drought problems made worse
-possibility of intense storms increasing soil erosion
all these effects will most likely impact upon humans, also causing…
-famine and conflict
-migration
what does sustainable management do?
- makes sure an environment can recover quickly from any use
- prevents damage to the environment
- helps local people get benefit from their environment
- helps local people understand the benefits.
what sustainable intermediate technology is used in hot arid regions?
- lining wells with concrete to avoid sewage contamination.
- hand pumps pump water up from deeper underground and the top of the well can be capped with a concrete cover to prevent contamination.
- water is stored in rain barrels for later use.
