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Date November 2021 Marks available 4 Reference code 21N.2.bp.2
Level SL and HL Paper 2 Time zone
Command term Explain Question number 2 Adapted from N/A

Question

The graph shows the trend in flood events worldwide between 1980 and 2000.

[Source: Hugo Ahlenius, UNEP/GRID-Arendal https://www.grida.no/resources/7199. Source adapted.]

Describe the trend in flood events.

[2]
a.

Suggest two ways in which increased global temperatures can cause changes in sea levels.

Way 1:

 

Way 2: 

 

[4]
b.

Explain two corporate strategies used to address global climate change. 

Strategy 1:

 

Strategy 2: 

 

[4]
c.

Markscheme

Award [1] for identifying the overall trend of increase over time and [1] for identifying the fluctuation/periods of decline.

Quantification required for full marks.

a.

In each case award [1] for identification of a valid way and [1] for further development of how it has led to changing sea levels.

For example: Glacial melt of continental ice [1]. Increased volume of ocean water resulting is sea level rise [1].

Other possibilities include:

b.

In each case award [1] for identification of a valid corporate strategy and [1] for further explanatory development/exemplification related to how it addresses global climate change.

For example: The Lego company has established emission targets for manufacturing and distribution in partnership with the WWF [1]. This will reduce the amount of greenhouse gas emissions which are responsible for climate change [1].

Other possibilities include:

c.

Examiners report

The resource was accessible to most candidates and the majority of responses were able to identify the overall increase shown by the graph. Although many also described the obvious fluctuation of the trend a number failed to gain full credit by omitting this characteristic. Candidates also need to be reminded of the importance of quantification when describing graphical resources.

a.

The majority of candidates were able to identify glacial melt and thermal expansion as causes of sea level change. Many answers developed explanations of the processes by which these led to sea level change with reference to overall increases in water stored in the oceans and volume changes. Some answers however were lacking in the development of how their selected ways led to sea level change and simply stated that they caused an increase in sea level. The question required causes and not just description and a more thorough analysis of its requirements would have directed answers to a more analytical approach. Some answers erroneously looked at the seasonal melting of sea ice and some tried to link sea level rise to increased evaporation and rainfall. Evaporation was credited where reference was made to shrinking inland seas, but this approach was very rare. Pleasingly a small number did refer to isostatic readjustment.

b.

This question produced a polarity of answers. Many candidates were able to identify strategies and link them to named companies and valid institutions. Assorted strategies were outlined such as carbon offsetting, waste reduction, use of IT for meetings, use of renewable energy and recycling and these were developed to demonstrate how they could address climate change. Answers frequently referred to the reduction of carbon emissions in elements of the production cycle. Responses that took this approach scored well. Some candidates were able to identify and describe a strategy but did not develop it to explain how it could be used to address climate change and here credit was limited. A significant number of answers did not recognize what was required with reference to corporate strategies and instead gave generic responses that simply addressed methods that could be used to combat climate change or examined international treaties. Candidates must ensure that all elements of the syllabus are covered in their revision.

c.

Syllabus sections

Unit 2: Global climate—vulnerability and resilience » 2.3. Responding to global climate change » 2.3.3. Civil society and corporate strategies to address global climate change
Unit 2: Global climate—vulnerability and resilience » 2.3. Responding to global climate change
Unit 2: Global climate—vulnerability and resilience

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