Lets be precise here: The CO2 from fossil carbon stores is chemically speaking exactly like other C02.
That said, increasing the concentration might not be smart anyways, -I don't know, at this point I'm not really sure. (I used to be very skeptic, now I'm starting to think it might be correct and the proponents just don't get PR.)
Do you or do you not believe in the link between the burning of fossil fuels and climate change? If you do not, I am not going to get into a theological debate with a believer.
That said, increasing the concentration might not be smart anyways, -I don't know, at this point I'm not really sure. (I used to be very skeptic, now I'm starting to think it might be correct and the proponents just don't get PR.)