> Concentrated CO2 is harmful. It causes discomfort, irritability, increases inflamation of asthma and other issues. I have never heard even the most retarded environmentalist claim that atmospheric CO2 is in danger of suffocating people, or any other plant or animal for that matter. > As CO2 in the atmosphere increases greenery also increases to compensate. The simple fact that atmospheric CO2 levels are higher now than 50 years ago conclusively disproves this hypothesis.