1. Climate ‘fix’ could deplete ozone
Unit 3 Ideas in Context P7(H) Paper
Paul Kerr
The Derby High School, Bury

2. What is climate and weather?
Climate – average weather conditions over a period of at least 30 years
Weather – current conditions in the atmosphere, e.g. Rain. The Sun drives all of the Earth’s weather systems

3. Changing temperatures

4. Correlation? Temp & C02 level rising 
Ice core evidence confirms similar changes in the past 
Scientists know C02 warms the atmosphere 
Computer models show global temperatures are related to rising C02 levels 

5. Cause? – The Greenhouse Effect

6. Changing Climates - Effects
Natural factors
Distance from the Sun changes
Amount of radiation from the Sun changes in cycles
Volcanic eruptions increase C02 levels
Human factors
Emission of greenhouse gases C02, CH4, H20 vapour

7. Changing Climates - Risks
Melting ice (glaciers and ice caps)
Rising sea levels (coastal changes)
Extreme weather
Effects on food and water resources
Human health (e.g. Malaria)
Financial (e.g. Insurance)

8. Changing Climates - Action
Use the car less Turn the heating down Use non-fossil fuels....
Buy local produce Reduce air travel Recycle more Avoid standby...

9. 1991 Mount Pinatubo Eruption

10. Volcanic Cooling
Sulfate (S02) particles reflect sunlight (Albedo) to counteract Global Warming
Sulfates provide a surface on which chlorine gases in POLAR stratospheric clouds can become activated causing chemical reactions that destroy Ozone (03) molecules
Atmospheric layers
Ozone (03) protects us by absorbing harmful UV radiation. After the eruption of Mt Pinatube 03 decreased over Antarctica

11. Sulfate Injection
Military jets and tanker aircraft or high altitude balloons could deliver sulfates into the stratosphere.
Clouds form due to sulfate injection.
Up to 90% reflection occurs, enhancing Albedo.
Geo-engineering or climate-engineering is a deliberate method of changing the Earth’s climate to try to counteract Global warming

12. The Ozone Layer Ozone production
Ozone absorbs dangerous UV radiation, protecting us below
Ozone destruction
Sulfates activate chlorine gases in polar clouds.
Cl + O3 → ClO +O2
A free oxygen atom can release the chlorine atom to do further damage
ClO + O → Cl +O2

13. Dr Simone Tilmes
I measured O3 levels in the atmosphere and used computer simulations to estimate future 03 loss if sulphate injections continued
Over the next 20yrs this could destroy as much as ¾ of the 03 layer over the Arctic
Arctic – North Pole

14. Dr Simone Tilmes
The expected recovery of ozone over Antarctic could also be delayed by about 30 to 70 yrs
Antarctic – South Pole
Sep 1979
Oct 2007
1987: Montreal Protocol. World agreement to ban CFC’s (Cl, F and C).
2050 fully repaired?
(2080 – 2130?)

15. Dr Simone Tilmes
More research is needed before society attempts global
geo-engineering solutions in the future.
We should not rule out this approach. Politicians will have to decide what is most important. They need to know what is good and bad about it.

16. Risks (bad) v Benefits (good)
Sulfate injection
Benefits
Reduce Global Warming
Risks
Ozone depletion
Holes in Ozone layer
Increased UV exposure leading to increased cases of skin cancer
Cancelling Sulfate injection
Benefits
Ozone layer protected
Risks
Global warming
Melting ice caps and glaciers
Rising sea levels
Extreme weather
Disease
Financial costs ?