1. How can the world stabilise carbon dioxide emissions?
Challenge:
How can the world stabilise carbon dioxide emissions?
Teachers’ notes

2. Using this challenge Learning outcomes
See Science at Work teachers’ notes.
Preparation
You may wish to obtain background information about the Kyoto Protocol for students.
Starter
Establish the context: What is climate change, and how is human activity contributing to it?
Main activity
Work through the slides. Answers are provided on Teacher slides 3 and 4. At Student slide 2, explore the idea of breaking up the problem of climate change into ‘wedges’. The wedges each represent a reduction in carbon emissions of 1 billion tonnes per year. Breaking the problem down in this way makes it manageable. A variety of today’s technologies could then be combined to tackle the issue.
At Student slide 7, emphasise that offsetting does NOT improve efficiency. It is an alternative approach that can limit the effects of car use in the short to medium term.
Plenary
Review the central premise: The wedges break a big problem down into specific areas that can be addressed using technology available today. This means we can tackle climate change now, without waiting for new developments.
Teacher slide 1

3. Using this challenge Differentiation – Easier
Student slide 1: Build on the cake idea. Students can think of this as a pie chart to represent the total emissions that must be ‘saved’. Each wedge is part of this total volume of carbon dioxide.
Differentiation – Harder
Extension: Break students into groups and ask them to discuss and report back on ideas for achieving further wedges of emissions reductions (energy efficiency in buildings, use of renewable and nuclear energy, biofuels and biological storage of carbon in forests are some examples). Students could also try the online game Carbon Crisis, which builds on the wedges idea ( – link opens in a new window).
Teacher slide 2

4. Answers
1. Climate change may have negative consequences, such as rising sea levels, unpredictable and severe weather. We may be unable to prevent, manage or overcome these problems.
2. Wedges break a single, seemingly insurmountable problem into many smaller problems. This allows scientists to identify a combination of technologies that can be combined to help reach a solution.
3. Transport is vital for the flow of goods and people that underpins the modern, global economy. (Hint: What products do we use? Where do our food and products come from? Where do we travel to?)
4. Single-occupant car journeys, empty lorries, low use of public transport, old and inefficient car engines, driving that reduces fuel economy. (Hint: Break this down into the things – engines, cars – and actions – driving, sharing – that could be improved.)
5. This question is open-ended but ideas could include engine fuel efficiency, driving speed (high speeds use more fuel), car sharing, local sourcing of food and goods, use of public transport. (Hint: Break down someone’s day and look at where they go and what they eat/use.)
6. More efficient engines have been developed, and smaller, lighter car models introduced.
Teacher slide 3

5. Answers
7. The car then emits less carbon dioxide for a given journey. (Hint: Think about total miles travelled in a week, and then the gallons of fuel required.)
8. Although the driver’s car emits carbon dioxide, targetneutral projects prevent or remove a similar amount of emissions. So, the driver's car use has no net (overall) impact on carbon dioxide emissions. (Hint: Think of adding and removing sand from a bucket – as long as the same amount is removed as is added, the bucket does not overflow.) This is NOT an efficiency improvement, but complements energy efficiency measures.
Teacher slide 4
© BP International Ltd 2008

6. How can the world stabilise carbon dioxide emissions?
Challenge:
How can the world stabilise carbon dioxide emissions?
Challenge presentation

7. The Carbon Mitigation Initiative
The world’s carbon dioxide emissions rise every year, causing an increase in the rate of global warming.
BP and the Ford Motor Company have sponsored the Carbon Mitigation Initiative (CMI) at Princeton University. CMI has identified many ways to reduce carbon dioxide emissions.
1. Why is it important to tackle climate change?
Student slide 1

8. The CMI concept of ‘wedges’
CMI’s solution uses the idea of ‘wedges’.
Wedges work like slicing up a large cake. You can’t eat it in one go, but you can slice it up and share the pieces.
Each of CMI’s wedges represents a reduction in the world’s carbon emissions of 1 billion tonnes.
2. How can wedges help to solve the challenge of climate change?
Student slide 2

9. Energy efficiency in transport
One way to save a wedge of emissions is to improve ‘energy efficiency’. Transport is one area we could work on.
3. Why is transport important today?
4. In what ways might transport not be energy efficient?
Student slide 3

10. What can governments do?
Governments control many aspects of how people use transport today. The state of California has passed tough laws to cut greenhouse gas emissions, including those from transport.
5. What are some areas that these laws could address? (Hint: Think about how people buy and use cars.)
Student slide 4

11. What can industry do?
The BP Carson refinery in California produces low emission fuels. These help drivers reduce their impact on climate change. Car makers have also responded to the California laws.
6. How might car makers have changed their cars to meet the new laws?
Student slide 5

12. What can drivers do? There are over 24 million cars in the UK.
Drivers can reduce emissions by choosing energy efficient cars, joining car share schemes or using environmentally friendly fuels that help reduce pollution and improve fuel economy.
7. Why does getting more ‘miles per gallon’ reduce the impact of using a car?
Student slide 6

13. Carbon offsetting
Another way to address emissions is to offset them. Offsetting works like a set of scales, as shown in the diagram.
BP has set up a non-profit initiative called targetneutral. Drivers can calculate their CO2 emissions, then contribute to projects that prevent or remove that amount of emissions.
8. Why does targetneutral reduce a driver’s impact on climate change?
Student slide 7