Global Warming Effects of increase CO2

1
Global WarmingEffects 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 ModelsPredictions

• What do climate models lead us to expect?

4
Climate ModelsWhat is the current effect of CO2

• A net extra forcing of around 2 watts per
  square metre

2 W/m2
5
An additional 2 watts per square metre of
radiative forcing

• Scientific American March 2004

6
Contributions toClimate Forcing
Climate Forcing (W/m2)
0
1
-1
Greenhouse gases Carbon Dioxide
Greenhouse gases Methane
Greenhouse gases Chlorofluorocarbons
Greenhouse gases Nitrous Oxide
Greenhouse gases Ozone
Aerosols Black Carbon
Aerosols Reflective aerosols
Aerosols Cloud droplet changes
Land cover changes
Sun
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Feedback
Climate Forcing
8
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