CO2 and methane as greenhouse gases (9.2) (R)

Question 1

What is the purpose of greenhouse gases in the atmosphere?

Answer 1

Greenhouse gases in the atmosphere maintain temperatures on Earth high enough to support life

Question 2

3 needed

What are some required examples of greenhouse gases?

Answer 2

• Water vapour
• carbon dioxide
• methane

Question 3

Describe the greenhouse effect

Answer 3

1. Electromagnetic short-wave radiation passes through the layer of greenhouse gases easily
2. The Earth’s surface absorbs most of the radiation and warms up.
3. The Earth’s surface radiates (reflects) energy as long-wave infrared radiation.
4. Some of the infrared radiation passes through layer of greenhouse gases into space.
5. Some of the infrared radiation is absorbed by greenhouse gases in the atmosphere (long-wave does not as easily pass through the layer of greenhouse gases)
6. The lower atmosphere warms up to point to allow life on Earth to exist

Question 4

Some human activities (…) the amounts of greenhouse gases in the atmosphere

Answer 4

increase

Question 5

2 needed

What greenhouse gases do human activities create more of?

Answer 5

• carbon dioxide
• methane

Question 6

How do humans increase the amount of carbon dioxide in the atmosphere?

Answer 6

By burning fossil fuels (in combustion)

Question 7

How do humans increase the amount of methane in the atmosphere?

Answer 7

Farming cattle releases methane

Question 8

What are many scientists theories about the increase of the temperature in the Earth’s atmosphere based on?

Answer 8

peer-reviewed evidence

Question 9

Describe many scientists’ theories about how human activities will affect the atmosphere?

Answer 9

many scientists believe that human activities will cause the temperature of the Earth’s atmosphere to increase at the surface

and that this will result in global climate change

Question 10

Why is there debate about whether climate change is real? What does this lead to?

Answer 10

It is difficult to model such complex systems as global climate change

This leads to simplified models, speculation and opinions presented in the media that may be based on only parts of the evidence and which may be biased

Question 11

What is the importance of peer review in climate change?

Answer 11

To check accuracy of evidence (data) and conclusions

Question 12

What is a major cause of climate change?

Answer 12

An increase in average global temperature

Question 13

4 needed

Describe some potential effects of climate change?

Answer 13

• glaciers and polar ice melting
• sea levels rising (due to thermal expansion and melting glaciers putting more water into ocean)
• patterns of rainfall changing, producing floods or droughts
• habitats changing

If you can’t recall one of these, pick another one (the specification only requests 4 of any)

Question 14

Discuss the scale, risk and environmental implications of global climate change

Answer 14

Scale - affects everybody and everything in the world

Risk - is already and will continue to disrupt the lives of potentially billions

Environmental impacts - reduced biodiversity, soil salinisation, desertification, etc

Question 15

What is the carbon footprint?

Answer 15

The total amount of carbon dioxide and other greenhouse gases emitted over the full life cycle of a product, service or event

Question 16

How can the carbon footprint be reduced?

Answer 16

By reducing emissions of carbon dioxide and methane

Question 17

6 needed, exhaustive non-specification list

What are some actions to reduce global climate change?

Answer 17

• Use alternative sustainable sources of energy for fuel (e.g. solar energy) rather than burning fossil fuels
• Taxing companies that fossil fuel to incentivise them to use more sustainable sources that don’t emit greenhouse gases
• Putting PV solar panels onto roof as source of energy
• Use electric cars or bikes rather than petrol/diesel ones
• Eat less meat - as meat industry produces much methane and greenhouse gases
• Improve insulation at home (e.g. double glazing) to reduce amount of gas needed to be burnt in boiler

Question 18

Why may actions to reduce global climate change be limited?

Answer 18

Economic of developing countries are based on energy obtained from cheaper, more abundant and more reliable fossil fuels