”on your link the fellow says 4 watts more will cause 1.2C warming. But that does *not* check. With total power 492W/m^2 from your diagram, maintaining the present temperature of 291K, an increase to 496 would only increase the temperature by (496/492) ^ .25 = 1.002026 times. Multiplying by the original 291K temperature, that means +0.59C, half of what the link stated. He evidently did not include the back radiation in the power maintaining the present temperature. It is of course only the proportional change in the total power the surface is receiving, that will cause (4th root) changes in the mean temperature.” - JasonC ( 4/23/01)
cogitator JasonC math is correct your link is not. There is nothing to argue about here.
I, and the climate science community in general, don't agree with JasonC's analysis. Feel free to believe him if you want to. I'm sure it makes you feel better.
I did research the question. JasonC's on shaky ground because he doesn't consider how the radiative forcing is actually translated into the physics of Earth's climate system.