MYTH 4: CO2 is the most common greenhouse gas.

FACT: Greenhouse gases form about 3 % of the atmosphere by volume. They consist of varying amounts, (about 97%) of water vapour and clouds, with the remainder being gases like CO2, CH4, Ozone and N2O, of which carbon dioxide is the largest amount. Hence, CO2 constitutes about 0.037% of the atmosphere. While the minor gases are more effective as "greenhouse agents" than water vapour and clouds, the latter are overwhelming the effect by their sheer volume and – in the end – are thought to be responsible for 60% of the "Greenhouse effect". Those attributing climate change to CO2 rarely mention this important fact.