----- IPCC 2007 WG-1 AR4 Carbon dioxide only causes 1.1°C of warming if it doubles. That’s according to the IPCC. Did you know that?
CO2 no-feedback sensitivity Climate Etc.
Hence, the CO2 no feedback sensitivity can only be calculated using models. Determination of the no feedback sensitivity has two parts:
¦calculation of the direct radiative forcing associated with doubling CO2
¦determination of the equilibrium change of global mean surface temperature in response to the CO2 forcing
The IPCC TAR adopted the value of 3.7 W/m2 for the direct CO2 forcing, and I could not find an updated value from the AR4. This forcing translates into 1C of surface temperature change. These numbers do not seem to be disputed, even by most skeptics. Well, perhaps they should be disputed.
So once we calculate the direct no feedback CO2 forcing (to a doubling of CO2,
it is often stated that all scientists agree that the Earth’s temperature would respond by increasing 1C.