John Holdren. The claim that this topic (mankind's use of fossil fuel and related CO2) is “extremely polarizing” among scientists and engineers is preposterous. The only scientists and engineers who consider the human influence on global climate to be controversial are (a) those who have not delved into the evidence and (b) those who are blinded by ideology. The national academies of science of every major country in the world that has one are unanimous in the view that human interference in the global climate system is a reality. This is a PowerPoint tutorial on what we know and how we know it. For another viewpoint, see article by Donald Rapp posted under "Warmers" titled "Climate Change, The Real Issues.".)
