I'm surprised by the number of posters here who think it's ok to insult Devo......sure his original post seems to be one-sided...but almost all of the responses here are blindingly one-sided on the opposite side of the coin....and most likely from individuals with no science background.
Science is a methodology where hypotheses are tested using multiple independent tests to provide statistically significant results either supporting the hypothesis or not. Experiments try to test the effect of some given variable on the system, by keeping other variables constant. If experiments support the hypothesis then it becomes an accepted theory...but it never becomes a scientific fact..because we can NEVER be 100% certain that a future experiment won't refine it such that our conclusions are shown to be erroneous. Basically...science can disprove theories...but it can never entirely prove theories.
When we talk about the carbon dioxide debate...whether it is significant in causing warming effects on a global scale....we are unable to utilize science in it's pure sense as no two tests can be considered independent...they all take place in the same system...our world....and are thus not independent. Nor can we only change one variable as almost infinite variables exist and change in our ecosystem that are beyond our control. Cause and effect on a global scale is almost impossible to rectify...at least using rational thought.
This "97%" argument..that 97% of scientists accept CO2 as being the major player here is very loosely thrown around......
A very well written and balanced article was written in Forbes yesterday...it talks about the 97%......
http://www.forbes.com/sites/warrenmeyer/2012/02/09/understanding-the-global-warming-debate/
Is CO2 the driving factor in rising global temperature? Who really knows?....But it appears unlikely. Is global warming happening?....Probably...but even that is not scientific fact...just a theory that has some evidence for it and some against. If global warming is happening what is causing it.....no one knows....the retreat of the last ice age....increases in solar activity....increases in water vapour in the atmosphere...there are complex feedback loops in our ecosystem the workings of which we have only started to scratch the surface of understanding.
I certainly don't have the answers....but I sure as hell know that none of you have them as well.