Earth Talk - Nature or Man?: Skeptics say people don't affect global warming that much; scientific bodies disagree

Upward of 800 skeptics (most of whom are not scientists) took part in the second annual International Conference on Climate Change -- sponsored by the Heartland Institute, a conservative research group -- in March. Richard Lindzen, the featured speaker and a meteorologist at the Massachusetts Institute of Technology, told the gathering that "there is no substantive basis for predictions of sizeable global warming due to observed increases in minor greenhouse gases such as carbon dioxide, methane and chlorofluorocarbons."