O-LevelGeographyThe natural environment2217/13 · Oct/Nov 2013 · Q525 Marks

Study Fig. 9, which shows information about the possible impacts of climate change in northern and eastern Canada. Climate change could be caused by an increase in greenhouse gases in the atmosphere. [Figure 9]

(a)(i)Name one greenhouse gas.[1]
(a)(ii)Identify from Fig. 9 a way in which climate change might: reduce energy demand; increase energy supply.[2]
(a)(iii)Identify three ways in which climate change might affect agricultural systems around the world.[3]
(a)(iv)Describe the possible impacts of climate change on the natural environment.[4]
(b)Study Fig. 10, a graph which shows average annual temperatures at Fairbanks, Alaska. [Figure 10]
(b)(i)Describe the changes in the average annual temperature in Fairbanks between 1906 and 2002. Refer to statistics and years in your answer.[3]
(b)(ii)Many scientists believe that global changes in temperature are due to the increase of greenhouse gases. Explain why greenhouse gases are increasing in the atmosphere.[5]
(c)For a named river, sea or lake which you have studied, describe the causes of water pollution. Name of river, lake or sea ..............................................................................................................[7]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2013). The mark or mark type is shown in brackets.

[1] (a) (i) Carbon dioxide, methane, ozone, nitrous oxide, water vapour
[2] (a) (ii) A. less heating needed (in winter); B. more HEP generated/increased forest productivity for wood to burn 2 @ 1 mark
[3] (a) (iii) Ideas such as: Extension of agriculture into areas to north/higher latitudes/nearer poles; Longer growing season; More drought/less water for crops to grow; Flooding of farmland; Changing temperatures affects growth of crops; etc. 3 @ 1 mark
[4] (a) (iv) Ideas such as: Temperature patterns change/some increase some decrease; Melting of ice cover/less icebergs/glaciers retreat; Rising of sea levels; Coastal flooding; Loss of/changing habitats; Extinction of species; Species may migrate permanently; Impact on ecosystems/food chains; Reduction in food/water supply for wildlife; Changing rainfall patterns/drought; Natural vegetation dies/grows in areas it previously didn't grow; Desertification/spread of deserts; Increased strength of /frequency of tropical storms; etc. 4 @ 1 mark
[3] (b) (i) Ideas such as: General rise over the period/temperatures have increased; From -3.3 to –2.2 (1.1) from (1906 to 2002)/–3.9 to –0.7 increase of –3.2; However fluctuations/not constant;(NB: not just min/max temps) e.g. 0.3 degrees in 1926, higher than –5.5 in 1956 (must refer to years and statistics here); etc. 3 @ 1 mark
[5] (b) (ii) Ideas such as: Generation of electricity; By using fossil fuels/in coal fired power stations (dev); Burning fuels/oils/petrol in vehicles/transport; Air travel; Deforestation; Which prevents use of carbon dioxide by trees; Ranching/grazing of cattle (releases methane); Factories burning coal; Incineration of waste; etc. 5 @ 1 mark or development
[L1] (c) Levels marking: Statements including limited detail describing causes of water pollution. (1-3 marks)
[L2] Uses named example. More developed statements describing causes of water pollution. (4-6 marks) (NB MAX 5 if no named example)
[L3] Uses named example (e.g. North Sea). Comprehensive and accurate statements including some place specific reference. (7 marks)
Candidates may refer to causes such as: Sewage disposal Industrial effluent Farming activities Nuclear waste Oil spillage etc.