Date | May 2019 | Marks available | 7 | Reference code | 19M.2.SL.TZ0.6 |
Level | Standard Level | Paper | Paper 2 | Time zone | Time zone 0 |
Command term | Suggest | Question number | 6 | Adapted from | N/A |
Question
Identify four strategies for limiting the impact of burning fossil fuels without reducing their use.
Suggest a range of practical procedures that could be carried out to measure the abiotic and biotic impacts of an oil spill in an aquatic ecosystem.
Even though there is growing global support for ecocentric values, the global consumption of fossil fuels continues to rise each year.
With reference to energy choices in named countries, discuss possible reasons for this situation occurring.
Markscheme
use of scrubbers on factories/power plants;
use of catalytic converters on vehicles;
regulating quality of exhaust gases;
using low sulphur coal resources;
restoring ecosystems damaged by pollutants / eg liming of acidified lakes;
sequestration/CCS;
afforestation/reforestation/reducing deforestation;
masks reducing inhalation of toxic gases/emissions;
building of sea defences;
vaccination/anti-malarial programmes;
Credit any responses identifying other valid strategies that don’t involve reducing fossil fuel use. Do not credit “increasing efficiency of vehicles/machinery using fossil fuels” ...these will only limit impact by reducing consumption, which is explicitly excluded by question.
[4 max]
identify a transect / sampling scheme to compare conditions over time/distance;
carry out multiple samples at each site to ensure reliability;
measure oil content/concentration using chemical tests;
measure light penetration using Secchi disc;
(use appropriate probes/meters/logging devices) to measure temperature/oxygen concentration/pH/salinity;
measure change in O2 concentration of samples kept in dark as a measure of BOD;
sample invertebrate populations using kick samples/Eckman grab/water samples;
Lincoln Index/mark-release-recapture may be used to quantify fish/larger invertebrates;
identify species present and abundance of each;
use this to calculate a biotic index evaluating sensitivity/tolerance of species present;
use similar data to calculate diversity with a diversity index;
count total numbers of birds/fish etc clearly impacted/killed by oil;
Credit any other procedures of equivalent detail and validity to those given above.
No additional credit for evaluating procedures/discussing impacts.
If response simply indicates measuring a named abiotic factor they can be credited for MP5 but can only gain one mark in total for any number of such factors. To gain further credit for other abiotic factors they should indicate some detail of the procedure beyond simple use of a probe/meter/logging device.
Award [4 max] for responses that address only biotic or only abiotic impacts.
[7 max]
The following guide for using the markbands suggests certain features that may be offered in responses. The five headings coincide with the criteria given in each of the markbands (although “ESS terminology” has been conflated with “Understanding concepts”). This guide simply provides some possible inclusions and should not be seen as requisite or comprehensive. It outlines the kind of elements to look for when deciding on the appropriate markband and the specific mark within that band.
Answers may include:
- understanding concepts and terminology of environmental value systems, ecocentrism, origins/influences on EVS, alternative energies, renewable/non-renewable, fossil-fuel technologies/infrastructure, impacts of global warming/climate change, sustainability, self-restraint, self-sufficiency, energy availability/affordability/reliability, energy security, etc;
- breadth in addressing and linking energy choices eg fossil fuels, renewables, nuclear etc and influences upon these choices through cultural, political, economic, technological, environmental, geographical factors etc Also factors influencing growth of ecocentrism eg education, cultural backgrounds, globalised media, climate change/energy-related disasters etc;
- examples of factors promoting fossil fuel energy choices eg availability of coal in Russia, fracking in USA, falling price of coal worldwide, etc and technological factors eg low technology in LEDCs, existing infrastructure in MEDCs etc and economic factors eg China’s dependency on industry, LEDCs seeking rapid economic growth etc and energy security issues eg Middle East oil, oil in USA, all kinds of fossil fuel in Russia, coal in China etc. Also, examples of influences promoting ecocentrism eg global social media, climate change disasters, NGOs eg Greenpeace, education on sustainability eg IB ESS, international movements eg UN Sustainable Development Goals etc;
- balanced analysis distinguishing and weighing against one another potential reasons for the simultaneous growth in both fossil fuel consumption and ecocentrism.
- a conclusion that is consistent with, and supported by, analysis and examples given eg “while the widespread impacts of fossil fuel use and globalised media have promoted a growing support for ecocentric values in the wider populace, it is the governments that ultimately make decisions and their priorities often lie with the economics and politics that favour the continued use of these fuels”;
[9 max]
Refer to paper 2 markbands, available under the "your tests" tab > supplemental materials.
Examiners report
Many candidates were able to identify appropriate strategies to reduce impacts without reducing the use of fossil fuels although these were often mixed with inappropriate strategies that did imply reduced use of the fuels.
Responses often failed to score well because they just listed factors that could be measured or described how they might be affected, but gave minimal or no practical details of how they could be measured.
Many candidates approached this question well, discussing difficulties with alternative fuels and economic and political pressures for the continued use of fossil fuels. Weaker responses had few relevant and specific examples and a limited range of different reasons for the paradox.