Nikolov and Zeller

The Mystery of Equation 8 refers, and offers me my title. For a while now, there has been some weird septic stuff floating around about how the planet is warmer-than-it-would-be-without-an-atmosphere not because of the greenhouse effect or anything like that, but because of gravity. Nikolov and Zeller I think, though for all I know others are thinking the same. There are several threads, and vast piles of comments, at WUWT - for example, this one; or the original. Since it was all obviously septic nonsense wrapped up in equations, I didn't even bother to think about it, in much the same way…