Skeptic commenter Jimbo provides a neat summary of the AGW argument:
Co2 is a greenhouse gas.
The world has warmed.
Man’s co2 has had a part in that warming.
But hang on a minute Jimbo:
The ocean heat content rose
The surface air temperature rose (UHI caveat on amount)
The troposphere temp rose
Outgoing longwave radiation increased.
CO2 and water vapour can’t create energy.
Therefore extra energy entered the system from outside via diminished cloud cover.
Therefore any extra heat from additional ‘greenhouse gases’ ‘trapping’ energy’ can only be a secondary factor, otherwise Outgoing longwave radiation would have decreased.
Therefore the majority of the warming has been caused by other, natural factors.