A-level Paper 1 2018

Question 1

Explain the role of cryospheric change in the water cycle. (4 marks)

Answer 1

• The cryosphere is a major store of water
• In a period of cooling (glacial period) the cryosphere grows in size. This is because the water cycle is slowed as ice stops the return of water to the sea.
• In a period of warming the cryosphere adds more water

Question 2

Analyse the data shown in figure 1. (4 marks)

Answer 2

P - The upper-middle countries have seen the fatest rates of growth of time periods
E - For instance, there has been a doubling from 9.8 to 18.3 gigatonnes of CO2 produced.
D - The industry appears to have doubled in its contribution to GHG in this group of countries (from 2 to 5 gigatonnes)
A - Poorest countries are not responsible for most GHG emissions
L - Low and low-middle countries contribute little to overall GHG emissions (e.g. in 2010 they produced 11.3 gigatonnes)

Question 3

Using figure 2 and your own knowledge, assess the challenges associated with reducing greenhouse gas emissions. (6 marks)

Answer 3

AO1:

• Human impacts (e.g. deforestation)
• Carbon budget
• Mitigation stategies (e.g. carbon sequestration technologies)
• Combustion

AO2:

• One challenge is obtaining agreements, especially those contributing more to global warming
• Another challenge is the whole agreement falling apart if countries like USA or China withdraw

Question 4

Assess the potential causes and impacts of changes to the water balance within a tropical rainforest that you have studied. (20 marks)

Answer 4

AO1:
* Processes changing the magnitude of water storage over time and space (e.g. evaporation)
* Drainage basins as open system
* Water balance shows balance between inputs/outputs
* Changes to water cycle (e.g. natural and human)
* Case study: Amazon rainforest

AO2:
* Human activities
* Climate change
* Local effects: vegetation and soil compaction increases flooding and runoff
* Regional effects: less precipitation increases temperature, evaporation. Decrease discharge.

Question 5

Analyse the data shown in Figure 3. (6 marks)

Answer 5

P - Population rises as precipitation falls
E - In 1970, the rain index is mainly positive to negative showing lower than average rainfall (-1.5 around 1990)
D - Population cotniues to rise from 1985 to 1990 as the rate marginally increases
A - One anomaly with no drought and famine. Suggests other factors
L - Famine correlates with drought, though locust outbreaks correlate with drought