Hot Arid Environments

Question 1

What is the average UK rainfall?

Answer 1

600mm of rainfall per annum

Question 2

State three ways Hot arid environments are characterised…

Answer 2

1) high temperatures
2) low and unreliable precipitation
3) sparse vegetation

Question 3

Describe the rainfall and temperatures in an arid area…

Answer 3

An arid area experiences less than 250mm of rainfall per annum.
Temperatures of 20-27degrees Celsius, extremes may go up to 49.

Question 4

Describe the rainfall and temperatures in a semi arid area…

Answer 4

Semi arid areas experience between 250 and 500mm of rainfall per annum.
Temperatures between 21 and 28degrees Celsius but temp does not go above 38 degrees Celsius

Question 5

Describe two points about the distribution of the world’s hot arid and semi-arid environments…

Answer 5

1) deserts situated around the tropics

2) deserted in the centre of large continental land masses (eg. gobi)

Question 6

State four factors which help to explain such high annual temperatures:

Answer 6

1) latitude
2) cloud cover
3) albedo
4) land and sea surfaces

Question 7

Describe how latitude helps to explain such high annual temperatures…

Answer 7

Places at lower latitudes receive more insulation, because of the angle of incidence. Less surface area to heat so Sun’s rays are concentrated.

Question 8

Describe how cloud cover helps to explain such high annual temperatures…

Answer 8

The lack of cloud cover associated with hot arid environments allows more of the short wave radiation emitted from the sun to reach the earth’s surface. (Clouds don’t block sunlight)

Question 9

Describe how albedo helps to explain such high annual temperatures…

Answer 9

Albedo is the percentage of solar radiation reflected by the earths surface. Hot arid areas have a low albedo, so not much radiation is reflected. Rocky/sandy/dark surfaces found in hot arid areas absorb most shortwave radiation rather than reflecting it.

Question 10

Describe how land and sea surfaces help to explain such high annual temperatures…

Answer 10

Large land masses heat more quickly than water but cool quickly too. Smaller surface area (don’t have to penetrate deeply into the sea) so land radiates heat quickly.

Question 11

State 5 human factors which make ecosystems more vulnerable:

Answer 11

1) mining
2) grazing
3) water abstraction
4) urbanisation
5) road, rail and airport construction

Question 12

State 3 physical factors which make ecosystems vulnerable:

Answer 12

1) slow growing plants
2) harsh climate conditions
3) dust storms can bury vegetation

Question 13

Name the general soil type in hot arid environments:

Answer 13

Aridisols

Question 14

State 5 points about aridosols:

Answer 14

1) thin (due to lack of chemical weathering)
2) infertile (due to lack of organic content)
3) lack essential minerals such as nitrogen and phosphorus because of lack of organic content
4) rapidly eroded during heavy seasonal rainfall
5) low water holding capacity because of their coarse structure

Question 15

What is the general name given to plants which have adapted to living in dry areas?

Answer 15

XEROPHYTES

Question 16

Give 3 examples of adaptations which XEROPHYTES might have…

Answer 16

1) swollen stems
2) thick cuticles
3) sunken or closed stomata
4) small leaves or spines

Question 17

Name the 5 factors causing aridity:

Answer 17

1) Latitude
2) Relief
3) Continentality
4) Prevailing winds
5) Cold Ocean Currents