Describe the distribution of hyper-arid and semi-arid regions in Africa.

Using located examples, suggest possible socio-economic impacts of climate change for arid and/or semi-arid environments.

Examine the importance of water in the development of the landforms in any one extreme environment (glacial, periglacial, or hot, arid).

Hyper-arid: a very broad band across much of north Africa (may list countries but expect a distribution-type comment) [1 mark]. Award [1 mark] for a further aspect of distribution, such as smaller distributions in south-west (Namibia) and in north-east Africa (accept east).

Semi-arid: award [1 mark] for each aspect of the distribution that is well-described or exemplified (e.g. found either side of the arid in the north); encircling the central/D R Congo/humid regions; discontinuous distribution in east Africa; widespread in southern Africa, especially in Botswana and Zimbabwe.

Climate predictions for arid and semi-arid areas are extremely varied. The approach taken will depend on the example used (e.g. some predictions for Sahel show increased, not decreased, rainfall).

Possible economic impacts include reduced crop yields, increased cost of irrigation water, cost of imports, the need for more dams etc. Negative impacts on economic activity may be linked to increased evaporation, water shortages, soil erosion, land degradation etc.

Social impacts for indigenous populations and settlements could include out-migration/loss of traditional nomadic cultures etc., increased prevalence of disease, conflict due to resource shortages, etc.

Award up to [4 marks] for the explanation of a range of socio-economic impacts and up to [2 marks] for the effective use of examples.

For example, in hot, arid areas, water action includes erosion and deposition by exotic, endoreic and ephemeral rivers. Flash floods can produce sheetwash. Features include canyons, wadis, alluvial fans and bajadas. Water is also important in weathering in desert areas (Griggs’ experiments). However, water action is not responsible for all desert land forms. Wind action forms dunes (barchans, seif, star etc.), deflation hollows, yardangs and zeugens.

A similar approach is valid for each of the other extreme environments. To achieve band E and above, particular landforms should be correctly identified and explained in a way that may acknowledge the contribution that other processes may also be making.

For answers examining more than one environment, only the highest scoring environment should be credited.

Marks should be allocated according to the markbands.

This was well done and the best candidates were able to articulate the patterns clearly. Weaker answers were vague and not geographical in nature.

Numerous answers were unable to suggest socio-economic impacts with located examples  and/or simply referred to aridity problems and did not relate these to climate change; others lacked detail or elaboration.

This part was very poorly done and only a few candidates were able to identify relevant landforms although there was little understanding shown regarding their development.