I'd be curious to see sources for that since every source I've read has said (roughly) 96% of CO2 is from natural sources.
If you were curious to see sources for that, you would have found them already, because they are trivial to locate. You are a liar, or can't use google. Which is it? I bring this up every time I see a global warming discussion on slashdot and related comments have often been scored up to 5; both mine, and replies to mine. I like to start by saying that we put out more than ten times as much as volcanism, perhaps you've seen the discussions before. No? How interested are you in this subject, again?
Consider the postage stamp: its usefulness consists in the ability to stick to one thing till it gets there. -- Josh Billings