Posted by Jeff Id on October 25, 2014
Doug Cotton has been dropping comments here for a couple of years now. Like many skeptic blogs, the threads become polluted with his unusual brand of CO2 based climate change denial. His argument has changed dramatically over the years but in fairness (or perhaps unfairness) to him, he says it has not. Now I think I have been more patient here than any other blog with his unusual proclamations but have been forced to snip many of his recent comment. Doug has even surpassed me as the most snipped commenter here and while I was well ahead of other readers he leaves me running a distant second.
I have spent a few days this week asking and Doug has spent time answering questions about his theory. Currently, he has talked himself into a very tight corner with respect to his CO2 doesn’t cause warming theory. In fact, it seems pretty clear to me that he has disproven his own theory but we are awaiting an answer. I decided to put it here because the old thread was way too long.
We are considering two planets with equal albedo. Both planets are dry and one has a non-absorbing Nitrogen (N2) atmosphere, the other has an absorbing Carbon Dioxide (CO2) atmosphere. They experience the same solar input and all other features are the same. Doug has proclaimed the truth of Loschmidt’s temperature gradient which matches the dry adiabatic lapse rate so we agree in the existence of the gradient, he has agreed that the planets each emit at the same temperature when viewed from space, and he admits that the average emission altitude of the CO2 planet is higher than the ground level emission of our Nitrogen planet.
If the atmosphere is cooler as we go higher in altitude, and the emission temperatures of both are the same yet the average emission altitude of the CO2 planet is non-zero, then the ground temperature of the CO2 planet must be warmer than the N2 planet – global warming theory is proven. Doug doesn’t seem to yet realize just how much of a pickle he has gotten himself into and at the time of writing this post he has gone offline for the night (in his area) but when he comes back, I anticipate he will explain how his theory can correct these statements such that his theory is not proven wrong.
I did not expect his admission of the above points as they completely disprove his conclusion that CO2 does not cause warming. He must rectify the conflict in his reasoning or concede the point.
We shall see.