Since we're not projecting a proof, the level of analysis is incidental to the data. I notice a correlation between umbrellas and water falling from the sky. Is there a causality? It needs to be determined. The same correlation exists between umbrellas and windshield wipers. Causality? The other possible explanations are coincidence and error, which can be revealed by replication.

In the case of CO2 there is some deduction that enters the picture. CO2 is a greenhouse gas (GHG.) (If you fill a vessel with it, and shine a light on it, it gets warmer than an identical vessel-light combination filled with air. Happens every time.) And then, the incidence of CO2 in the atmosphere has increased by 40% in the industrial age. That's after a million years of virtually no change. The conclusion implied by those premises is that the atmosphere is warming.

The predictions based on those models were set down 40 years ago. Temperatures, ocean levels, glacial decreases, droughts, storms, etc. It's happening. The warming, its feedbacks, the climate sensitivity -- is pretty much settled, unless you have some revolutionary information. If it's not CO2 behaving as predicted and expected, burden is on you to show how, and what it then might be. Solar cycles, Milankovitch cycles, and obliquity cycles have been proposed, and ruled out. You'll have to think up something new, and a way of detecting it.

--imm