Date | November 2016 | Marks available | 6 | Reference code | 16N.2.bp.5 |
Level | SL and HL | Paper | 2 | Time zone | |
Command term | Explain | Question number | 5 | Adapted from | N/A |
Question
The diagram shows the proportions of land and water at each degree of latitude and the locations of some cold extreme environments.
(i) Estimate the latitude at which the percentage of land is highest in the Northern Hemisphere.
(ii) State one reason why extreme cold environments can even be found at latitude A.
(iii) Briefly outline the seasonal variations in temperature likely to be found at latitude B.
Explain the characteristics and formation in periglacial environments of:
(i) patterned ground;
(ii) thermokarst.
Referring to examples, evaluate the varied economic opportunities in hot, arid environments.
Markscheme
(i) latitude: 67° North (accept 65–70° N inclusive) [1]
[1 mark]
(ii) altitude/elevation [1]
[1 mark]
(iii) Award [1] for each of the following:
- most months below freezing
- wide range of monthly temperatures
- lowest temperatures (–40°C) in June/July
- highest temperatures (could reach +5°C) in November/December.
[2 marks]
(i) Award up to [2] for a description of the characteristics and up to [2] for an explanation of formation, up to a maximum of [3].
Characteristics include:
- patterned ground consists of stone-circles, polygons and stripes [1]
- they can be up to several metres wide [1].
Formation points include:
- formation occurs in soils that have experienced intense frost heave [1]
- steep slopes/gradient cause the circles to be replaced by polygons [1]
- role of ice sorting/differential frost heave [1]
- solifluction may play a role [1].
[3 marks]
(ii) Award up to [2] for a description of the characteristics and up to [2] for an explanation of formation, up to a maximum of [3].
Characteristics include:
- wet hollows/depressions/lakes [1]
- uneven/irregular relief/hummocks [1].
Formation points include:
- permafrost melting, leading to wet areas/lakes [1]
- ice lens growth explaining hills/hummocks/higher areas [1]
- doming due to frost heave [1]
- warming climate may explain increased thermokarst [1].
[3 marks]
Most hot environments are not densely populated due to the challenging nature of the environment. Expect details of opportunities to include forms of agriculture including nomadism (the traditional way of dealing with insufficient amounts of rainfall and pasture) or commercial crops in places with irrigation (in areas close to rivers or oases), eg cotton, dates.
Other examples include mineral and oil exploitation, or possibly tourism using the arid environment as an attraction (either natural features or cultural landscape, eg world heritage sites).
Good answers may evaluate the relative merits of these opportunities (eg high value of oil and some tourism industries compared with the low profitability of some forms of agriculture). Good answers may also evaluate the sustainability/durability of some types of activity. Another approach might be to evaluate the likelihood of opportunities being exploited, or not, in different places (eg conflict or local poverty could deter potential visitors in some arid places).
At band D, two opportunities should be described.
At band E, expect either more detailed explanation of two opportunities or some evaluation of how the opportunities may vary in terms of potential/realized benefits (eg for different places, environments, societies or levels of development).
At band F, expect both.
Marks should be allocated according to the markbands.
[10 marks]
Examiners report