The Reef Tank has kindly republished one of the How to Talk to a Climate Skeptic articles, the one about the claim that observed temperature increases indicate a much lower sensitivity to doubled CO2 than the general consensus figure of 3oC.
It is an old argument, but it still comes up frequently here and elsewhere so bears some repeating.
You can not use only the current temperature to assess sensitivity to 35% increased CO2 because:
- the oceans have a large heat capacity so it will take several decades to see the full effect
- CO2 is constantly rising
- CO2 is not the only factor affecting climate