1. Another bad point about deforestation…
More trees = more microbes (bacteria) in the soil to help decay

3. The Greenhouse Effect

4. Problems caused by an Increased Green House Effect

5. Exam Questions
19 marks

6. 1 = D
2 = A
3 = C
4 = B

7. This question is about global warming
This question is about global warming. Match words, A, B, C and D, with the numbers 1– 4 in the sentences.
A carbon dioxide
B greenhouse
C ice caps
D sea
Methane and in the atmosphere absorb much of the energy radiated by the Earth.
This can increase the effect and cause the Earth’s atmosphere to become warmer.
An increased temperature of only a few degrees Celsius may melt the and cause a rise in levels.
1 = A
2 = B
3 = C
4 = D

8. The burning of forests to create more land for growing rice is affecting the environment.
Match words, A, B, C and D, with the numbers 1– 4 in the sentences.
A biodiversity
B carbon dioxide
C energy
D methane
Forests remove from the atmosphere.
Cutting down forests reduces the amount of
Growing more rice is increasing the amount of in the atmosphere.
The greenhouse effect is caused by the re-radiation
of back to the Earth.
1 = B
2 = A
3 = D
4 = C

9. This question is about global warming.
A How does an increase in greenhouse gases in the atmosphere lead to an increase in global warming?
1 More of the radiation from the Sun passes into the atmosphere.
2 The atmosphere radiates more energy back to Earth.
3 The Earth radiates more energy back into the atmosphere.
4 The sea absorbs more energy from the Sun.
B Forests are often cut down to clear land for growing crops. Keeping forests rather than cutting them down for growing crops helps to reduce global warming because . . .
1 carbon dioxide can be ‘locked-up’ in wood for many years.
2 growing crop plants increases the number of microorganisms in the soil.
3 forests release large amounts of carbon dioxide.
4 some crop plants remove sulfur dioxide from the atmosphere.

10. 7C Scientists use computer models to predict increases in global temperature.
The table shows the predictions for global temperature increases from 2000 to 2100 produced
by different models.
Which two predictions are in closest agreement?
1 Rand S
2 Sand T
3 Tand U
4 Vand W
7D The predictions made by using the different models vary because . . .
1 the instruments that scientists use are not sensitive enough.
2 scientists do not have sufficient data on how different factors affect global temperatures.
3 some of the scientists do not have appropriate computer programming skills.
4 it is impossible to do experiments connected with global warming.

11. The areas where mangrove forests have been destroyed and removed are used as landfill sites.
Landfill sites are used to dump waste which is then covered with soil.
As the waste decays methane gas is produced.
Methane can contribute to . . .
1 the production of acid rain.
2 rising sea levels.
3 the greenhouse effect.
4 water pollution.

12. B The landfill sites created by burying waste are used to build tourist resorts. This decreases the land available for animals and plants and may cause . . .
1 global warming.
2 a rise in the Earth’s temperature.
3 rising sea levels.
4 the loss of organisms for future use.
C Cutting down large numbers of mangrove trees causes . . .
1 a reduction in the biodiversity of animals living in mangrove swamps.
2 an increase in the level of methane in the swamp water.
3 an increase in the release of oxygen to the atmosphere.
4 an increased rate at which carbon dioxide is removed from the atmosphere.

13. 19 marks A* = 18 A = 17 B = 15 C = 13 D = 11 E = 9 F = 7
Exam Questions
19 marks
A* = 18
A = 17
B = 15
C = 13
D = 11
E = 9
F = 7