Robert C. Balling, Jr. -Former Director of Climatology current GIS-MAS program director, School of Geographical Sciences Arizona State University
"There is no doubt that CO2 is a greenhouse gas, and holding everything else constant, elevated CO2 will act to warm the Earth. But as we see in the CO2 story, the levels of this gas have fluctuated enormously over the history of the Earth, and the ecosystems of the planet have evolved to cope with these variations. To suddenly label CO2 as a "pollutant" is a disservice to a gas that has played an enormous role in the development and sustainability of all life on this wonderful Earth."
"An Inconvenient Truth" is billed as the scariest movie you'll ever see. It may well be, but that's in part because it is not the most accurate depiction of the state of global warming science. The enormous uncertainties surrounding the global warming issue are conveniently missing in "An Inconvenient Truth."