The Supreme Court rules that the EPA can regulate auto emissions of greenhouse gases. And a new report from the U.N.'s Intergovernmental Panel on Climate change predicts increased hunger, water shortages and massive floods as the world's temperature rises.
Michael Robinson-Dorn, assistant professor of law; director, Berman Environmental Law Clinic at the University of Washington School of Law
Vicki Arroyo, director of policy analysis at the Pew Center on Global Climate Change
Linda Mearns, senior scientist, director of the Institute for the Study of Society and Environment; National Center for Atmospheric Research