Date | May 2015 | Marks available | 4 | Reference code | 15M.1.bp.3 |
Level | SL and HL | Paper | 1 | Time zone | |
Command term | Distinguish | Question number | 3 | Adapted from | N/A |
Question
The graph shows total carbon dioxide (CO2) emissions by region from 1990 to 2010.
Describe the trend of CO2 emissions in Asia between 1990 and 2010.
Suggest two reasons why CO2 emissions in Europe have decreased since 1990.
Distinguish between global climate change and the enhanced greenhouse effect.
Markscheme
Any two valid descriptive points for [2] plus [1] for accurate quantification/use of data from the vertical axis (actual figures or proportions).
- The emissions have increased.
- Sharp rise in emissions after 2002.
- Emissions relatively stable in the 90s.
Award [1+1] for each valid and distinct reason, provided that it is developed by means of detail and/or exemplification.
For example: Development of renewable/alternative sources of energy [1] replacing fossil fuels [1].
Possibilities include:
- policies to reduce use of fossil fuels (including Kyoto protocol)
- political will (including growth of green parties)
- more efficient vehicles/appliances
- improved public transport systems
- education/increased awareness lowering consumption
- industries relocating outside of the region.
Credit should also be given to attempts to explain the decrease by referring to periods of economic recession.
Award [1] for a valid description of global climate change and [1] for a valid description of the enhanced greenhouse effect. The final [1+1] are reserved for any two valid distinguishing characteristics between the two.
Descriptions:
Global climate change is the change in the global pattern of climate precipitation, temperature, winds, pressure systems). The enhanced greenhouse effect is the increasing amount of greenhouse gases in the atmosphere as a result of human
activities.
Distinguishing characteristics could be:
- GCC can relate to any aspect of climate whereas the EGE specifically impacts upon temperature
- GCC can have natural causes whereas the EGE is anthropogenic
- GCC can involve cooling/glacial periods whereas EGE is associated with global warming
- EGE is a major cause of GCC.
Examiners report
On the whole there were no problems describing the trends with a smaller increase in emissions until 2002 after which they increase significantly. The quantification, however, was mostly poorly done since many candidates read the upper boundary of the Asian plot rather than the compound values. This limited many responses to 2 of the 3 marks available.
Mostly good answers with reference to the outsourcing of many polluting industries to elsewhere; increased awareness of the governments and individuals; targets linked to agreements like the Kyoto protocol; increased usage of renewables like wind or alternatives like nuclear; etc. Some responses were a bit minimalistic and lacked development or failed to identify two reasons that were distinct.
A few very clear full mark responses that accurately described what each of these are and how they differ or are linked. Unfortunately many responses struggled to correctly understand what the enhanced greenhouse effect is, with much confusion about radiation and irrelevant reference to ozone. Often they were accurately described but the distinguishing characteristics were not presented clearly.