I don't think the real issue is that man has "no effect" on the earth's atmosphere.
The issue is one of the "relative effect" of man vs nature.
Do the math. Man's effect is dwarfed by nature. The sheer volume of the atmosphere, area of the earth's surface, area of the surface of the atmosphere at the edge of space, and continuous energy input by the sun dwarf all of man's effects.
The models they cite as showing man changing the climate also show that if man stopped doing what he is doing, it would have a minuscule "correcting" effect. If that is the case, then it means our effect in causing the "anomaly" is also minuscule. Hence, the draconian actions recommended have an enormous price for minuscule effect. In other words, it is a bad deal.
Very true.
We can mathematically prove that man creates around 0.6 Deg C on the earth. We can mathematically prove every animal and insect creates. But there is no catastrophic warming in effect.
don't worry mefistofelerevised the sky isn't falling.
Here is a real simple video on this:
http://www.youtube.com/watch?v=TjHLWwbN0SM