J.R. Dunn had a nice essay in The American Thinker on January 31, titled, “Resisting Global Warming Panic.” Key graf:

“One curious element involves certain facts that, on first consideration, would appear to be crucial but never seem to come up in debate. I have spent several years trying to track down the actual values of two numbers – the annual amount of carbon dioxide emitted by all human activities, and the amount of carbon dioxide already present in the atmosphere. There are as many answers as there are sources, the first ranging from 3 billion to 28 billion tons, the second from 750 billion tons to 2.97 x 1012 tons, a number so large that there’s no common English word for it. Variations of this size – up to three orders of magnitude – suggest a serious lack of basic knowledge. The fact that it never comes up suggests that scientists are well aware of this. (It’s doubtful we’ll see the question addressed in this week’s IPCC report either.)”

I note, however, that the weight of the atmosphere is calculable, though very, very large, of course. A millibar is a measure of atmospheric weight. And if he know how much the atmosphere weighs, and what the usual percentage of CO2 in the atmosphere is, we ought to know how much carbon dioxide is “already present in the atmosphere.”