IBDP Geography -Option C – Extreme environments futures-IB style Questions HLSL Paper 1

Question

The map shows different levels of aridity in Africa and the areas at most risk from climate change.

Describe the distribution of hyper-arid and semi-arid regions in Africa.[2+2]

a.

Using located examples, suggest possible socio-economic impacts of climate change for arid and/or semi-arid environments.[6]

b.

Examine the importance of water in the development of the landforms in any one extreme environment (glacial, periglacial, or hot, arid).[10]

c.
Answer/Explanation

Markscheme

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.

a.

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.

b.

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.

c.

Examiners report

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

a.

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.

b.

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.

c.

Question

(i) Define the term aridity.

(ii) Define the term infertility.[4]

a.

Explain three factors, other than aridity and infertility, that affect the sustainability of human activities in extreme environments.[6]

b.

“Periglacial areas offer more opportunities for human activities than hot, arid areas.” Discuss this statement.[10]

c.
Answer/Explanation

Markscheme

(i) Aridity refers to a lack of moisture [1 mark]. Award a further [1 mark] for quantification (precipitation less than 250 mm), or a link with evapo-transpiration rates.

(ii) Infertility refers to the lack of nutrients/bases in soils [1 mark]. Award a further [1 mark] for recognition of lack of biomass; or low weathering rates/inputs of nutrients; partial decomposition; insufficient to supply plant-based agriculture/crops.

a.

The factors may either promote or reduce sustainability. Possible factors include population density (possibly leading to usage exceeding carrying capacity), changes to natural vegetation/habitat (likely to decrease carrying capacity), overuse (whether for agriculture, grazing, mining, tourism), the implementation of conservation measures, provision of irrigation (provided source of water is sustainable), etc. Award [1 mark] for identifying/describing each valid factor and a further [1 mark] for development or exemplification.

b.

Opportunities in both cases are widespread and include farming/cattle herding, mineral extraction, and tourism. Problems are likely to include climate, remoteness, and inaccessibility – as well as low temperatures in periglacial areas, as opposed to a lack of water in hot desert areas.

Opportunities could be for a range of players/stakeholders, including local people, TNCs/energy companies, tourists.

Answers should cover opportunities in both periglacial areas and hot, arid areas.

The use of only one extreme environment which includes a range of opportunities is unlikely to progress beyond the D/E border.

To access band E both environments should be considered.

At band F expect detailed examples of opportunities in both environments and a clear conclusion.

Marks should be allocated according to the markbands.

c.

Question

Outline two physical causes of aridity in hot, arid environments.[4]

a.

Explain two processes of weathering commonly found in hot, arid environments.[6]

b.

“Human activity within periglacial environments is unsustainable.” Discuss this statement.[10]

c.
Answer/Explanation

Markscheme

Sub-tropical high pressure [1] brings dry, descending air [1].

Continentality / interior has higher temperatures than coastal margins [1] due to lack of proximity to the sea [1].

Cold offshore currents [1] mean air does not rise / limits potential precipitation over land [1].

Rain shadow effect [1] means a lack of moisture/rain/water for places on lee side/far side/downwind of relief features/mountains [1].

[4 marks]

a.

Possibilities include:

  • exfoliation (involves layers of rock peeling off)
  • granular and block disintegration (rock breaks down into grains/blocks)
  • freeze-thaw (blocks break off due to ice expansion)
  • salt crystal growth (crystals in pores create stress).

Do not credit erosion processes such as sand abrasion.

Award [1] for each process outlined (not simply named) and a further [2] for the brief explanation offered.

For example: Exfoliation involves layers of rock peeling off [1] due to expansion/contraction due to (large) temperature range/changes [1] in the presence of some moisture/water [1].

[6 marks]

b.

Sustainability has been defined in a number of ways. One common one is using resources wisely without compromising the needs of future users. Within an extreme environment the resource base is quite fragile. There are a variety of approaches to analysing the question based on sustainable activities.

Indigenous people have generally lived sustainably in these environments. More recent activity by newer arrivals has not been as sustainable. Human activity includes settlement, infrastructure, communications, and resource development, including tourism. This more recent development has had adverse effects not only on the environment, eg degradation of soil or fauna within ecosystems, but perhaps on the culture of indigenous people.

Good answers may discuss the concept of sustainability and the degree to which environmental, social and economic needs can all be met in periglacial environments. Good answers might be carefully structured around different periglacial environments/places/levels of development and may discuss the extent to which sustainable goals can be met in each.

At band D, two human activities should be described and their sustainability commented on.

At band E, expect either more detailed explanation of different activities, or some discussion of the concept of sustainability in relation to periglacial environments.

At band F, expect both.

Marks should be allocated according to the markbands.

[10 marks]

c.

Question

Outline two ways in which people have adapted their outdoor activities to extremes of weather in hot, arid environments.[4]

a.

Distinguish between the terms “accumulation” and “ablation” in the glacial environment.[2]

b.i.

Explain two reasons why many glaciers are retreating.[4]

b.ii.

“Global climate change will create more opportunities than challenges for indigenous populations.” Discuss this statement, with reference to one or more extreme environments.[10]

c.
Answer/Explanation

Markscheme

In each case, award [1] for the factor and [1] for further development/ exemplification.

For example: People wear long, loose / light-coloured robes/clothes [1] as such garments allow air to circulate / reflect insolation [1] / provide protection from the sun during the day and are warm at night [1].
Turbans provide protection from the sun [1] and can be wrapped around the face in sand storms [1].
Nomadic herders stay in tents [1] that are easily dismantled and moved [1].
Daily routine [1] – work done in the cool of the morning [1].
Nomadic herders move their animals [1] in order to be close to sources of water during a dry season [1].

Long term-agricultural adaptations that reflect climatic conditions (such as irrigation) are not acceptable.

Accept other valid suggestions.

a.

Award [1] for each statement. Two simple statements (no need for explicit distinction) acceptable for [2].

• Accumulation – increase of snow and ice on the glacier [1].
• Ablation – the melting of glacial ice [1].

b.i.

In each case, award [1] mark for the factor and [1] for further development.

Possible reasons include:

• global warming (either caused by humans or part of a natural cycle)
• changes in precipitation levels
• increased volcanic activity
• changes in ocean currents
• El Niño
• sunspot activity.

For example: Many glaciers retreat due to higher temperatures / global warming [1] caused by enhanced greenhouse effect [1].

b.ii.

There are many different indigenous populations that may be used. Examples include, but are not limited to, the San, Tuareg, Fulani, Inuit, Nenet, Saami.

The question is not limited to one area, so references may be made to more than one indigenous population and more than one extreme environment.

Indigenous peoples are among the first to face the direct consequences of climate change, owing to their dependence on, and close relationship with, the environment and its resources (for food, cultural identity). Climate change exacerbates the difficulties already faced by vulnerable indigenous communities, including political and economic marginalization, loss of land and resources, human rights violations, discrimination and unemployment.

However, global climate change in the Arctic may bring increased navigation during the winter, and a warmer climate has lengthened the growing season so potential yields may increase, more opportunities for sedentary agriculture / forestry / tourism / sea fishing / hunting.

Opportunities / benefits in hot, arid areas may include better grazing potential, more food production and more reliable water supplies.

Some may argue that climate change will have little or minor effect on their chosen example.

Good answers should progress beyond simply agreeing with, or rejecting, the statement and will discuss the validity of the statement by considering such things as the scale of the climate change, the degree to which indigenous population groups have assimilated in society, etc.

Another approach might be to provide a structured discussion of different kinds of opportunities and challenges found in an extreme environment and arrive at an evidenced conclusion.

At band D, expect some description of impacts on an indigenous population. (including answers that do not specify who the indigenous peoples are).

At band E, expect either more detailed explanation of opportunities and challenges for indigenous populations or a structured evaluation of the statement.

At band F, expect both of these elements.

Marks should be allocated according to the markbands.

c.
Scroll to Top