[ClearCase_guy]

Look at Post #7, the last graph, showing levels of CO2 over time. It fluctuates in a consistent pattern that has nothing to do with human activity, as much of this graph covers time prior to man's industrialization.

Proof that the rise is not due to man? No.
Reasonable doubt? You bet.

[cogitator]

It's always surprising to me that some people think there is doubt about the anthropogenic cause of the currently-observed rise in atmospheric CO2 concentrations (what the Keeling curve displays). I don't even include this in my profile because there are so many other good sources on the Web that address this subject. Below are five different links on this subject. If you think there's doubt after perusing these links... well, then you could never be convinced that it gets darker at night based on arguments that the Sun is not visible then.

The first one, from 1996, dates back to the heyday of Usenet, and contains an itemized list of various types of evidence. I have used some of these points in different FR discussions.

Why does atmospheric CO2 rise ?

"The CO2 rise is natural"

How do we know that recent CO2 increases are due to human activities?

How Do We Know that the Atmospheric Build-up of Greenhouse Gases Is Due to Human Activity?

Ice Bubbles Reveal Biggest Rise in CO2 for 800,000 Years

Reasonable doubt? You bet.

Maybe O.J. didn't murder Nicole and Ronald Goldman, either.