Editor;
Re: Myths about global warming (PM Mailbag Friday, 25 December 2015) – “MYTH 4: CO2 is the most common greenhouse gas.” It is not. It is the most abundant non-condensing greenhouse gas. This means, that unlike water vapor, which can only be a feedback, CO2 can be a forcing as well as a feedback. Most of the heat absorbed by greenhouse gases are absorbed by water vapor, but it is CO2 which initiates the change in temperature.
NiCuCo
