The Carbon Cycle (AQA A Level Geography): Exam Questions

Exam code: 7037

3 hours15 questions
1
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4 marks

Outline the process of decomposition in the carbon cycle.

2
4 marks

Explain how the extraction and burning of fossil fuels affects the carbon cycle.

3
4 marks

Outline the processes involved in transferring carbon from the atmosphere to ocean stores.

4
4 marks

Describe the main stores within the global carbon cycle.

1
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6 marks

Figure 2 shows a simplified version of Europe’s forest carbon cycle.

Figure 2

A simplified version of Europe’s forest carbon cycle

europes-forest-carbon-cycle

Using Figure 2 and your own knowledge, assess the implications of the data for attempts to manage carbon transfers.

2
6 marks

Study Figure 2, which shows the 'estimated size of major global carbon stores between 1750 and 2020'.

Carbon Store

1750 (GtC)

2020 (GtC)

Change (GtC)

Atmosphere

590

860

+270

Terrestrial (vegetation + soil)

2,000

1,850

−150

Surface ocean

900

920

+20

Deep ocean

37,000

37,020

+20

Lithosphere (fossil fuels)

4,000

3,700

−300

Source: Adapted from the Global Carbon Project and IPCC Sixth Assessment Report, 2021.

Using Figure 2 and your own knowledge, assess the challenges posed by changes in the size of global carbon stores.

3
6 marks

Analyse the changes in annual deforestation rates in the Brazilian Legal Amazon shown in Figure 1.

Figure 1: Annual deforestation in the Brazilian Legal Amazon, 1995–2023

Year

Annual deforestation (km²)

1995

27,000

2004

27,800

2012

4,500

2019

10,100

2021

13,235

2023

5,800

Source: INPE PRODES annual deforestation monitoring, Brazilian Legal Amazon. Units: square kilometres of primary forest cleared per calendar year.

4
6 marks

Using Figure 2 and your own knowledge, assess the challenges of changes to the global carbon system.

Figure 2: Global carbon budget — annual fluxes, 2010–2019 average

Carbon flow

Annual flux (GtC yr⁻¹)

Fossil fuel and industry emissions

+9.5

Land-use change emissions (incl. deforestation)

+1.6

Ocean uptake (sink)

−2.5

Land uptake (sink: vegetation and soils)

−3.4

Net annual atmospheric increase

+5.2

Source: Adapted from Global Carbon Project (Friedlingstein et al., 2020). Positive values = carbon added to atmosphere; negative values = carbon removed. 1 GtC = 1 billion tonnes of carbon.

5
6 marks

Using Figure 2 and your own knowledge, assess the implications of attempts to manage carbon transfers.

Figure 2: Estimated annual carbon transfers managed by leading mitigation strategies, global, 2020

Strategy

Annual carbon managed (GtCO₂ yr⁻¹)

Direction of transfer

Renewable energy displacing fossil fuels

2.6

Avoided release: lithosphere → atmosphere

Avoided deforestation (REDD+, forest codes)

1.4

Avoided release: biosphere → atmosphere

Afforestation and reforestation

0.9

Active uptake: atmosphere → biosphere

Soil carbon sequestration (agriculture)

0.4

Active uptake: atmosphere → pedosphere

Carbon capture and storage (CCS)

0.04

Active uptake: atmosphere → lithosphere

Source: Adapted from IPCC AR6 WG3 (2022) and IEA energy transition data. Values are global estimates, rounded for clarity.

1
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20 marks

Assess the impact of farming practices on the carbon budget.

2
20 marks

Evaluate the extent to which human activities are responsible for changes in the water and carbon cycles.

3
20 marks

With reference to a tropical rainforest that you have studied, evaluate attempts to mitigate the impacts of climate change.

4
20 marks

Evaluate the potential impact of changes in the carbon budget on a tropical rainforest you have studied.

5
20 marks

To what extent does an understanding of feedback systems in the carbon cycle help with attempts to mitigate the impacts of climate change?

6
20 marks

Evaluate the potential impact of changes in the carbon budget on a tropical rainforest that you have studied.