There is a better explanation for global warming than air pollution, two Harvard researchers say: the Sun is increasing in brightness and radiance.
"Changes in the Sun can account for major climate changes on Earth for the past 300 years, including part of the recent surge of global warming," claims Sallie Baliunas, an astronomer at the Harvard-Smithsonian Center for Astrophysics (CfA).
"We're not saying that variations in solar activity account for all of the global rise in temperature that we are experiencing," cautions her CfA colleague, astrophysicist Willie Soon. "But we believe these variations are the major driving force. Heat-trapping gases emitted by smokestacks and vehicles -- the so-called greenhouse effect -- appear to be secondary."