1. Global Warming Effects of increase CO2

2. Carbon dioxide
Can we be completely sure that the climate changes we observe are caused by anthropogenic emissions of carbon dioxide?
Not completely sure
But it is likely:

3. Climate Models Predictions
What do climate models lead us to expect?

4. Climate Models What is the current effect of CO2
A net extra ‘forcing’ of around 2 watts per square metre…
Average 240 W/m2
Average
240 W/m2
150 W/m2
On Average
390 W/m2
+ 2 W/m2

5. An additional 2 watts per square metre of ‘radiative forcing’
Scientific American March 2004
From Scientific American

6. Contributions to Climate Forcing
Climate Forcing (W/m2) -1 +1
Greenhouse
gases
Carbon Dioxide
Methane
Chlorofluorocarbons
Nitrous Oxide
Ozone
Aerosols
Black Carbon
Reflective aerosols
Cloud droplet changes
Land cover changes
Sun

7. Increased Climate Forcing Increased Water Vapour Negative Positive
Feedback
Increased
Climate Forcing
Increased
Water Vapour
Negative
Positive
Climate
Forcing
Global
Temperature
More Evaporation
Decreased
Climate Forcing
Increased
Cloud Cover

8. Probably the best we can hope for in the next century.
The Future…
CO2 levels will rise
Very roughly,
If we make a 50% cut in GLOBAL emissions
CO2 will stabilise at twice historical levels
Probably the best we can hope for in the next century.

9. IPCC Predictions…