Representatives of nearly 200 countries, including the United States, are meeting in Doha, Qatar in an effort to stem greenhouse gases and slow the warming of the planet. Almost everyone agrees it's a global problem that demands a global solution. What promises should the U.S. make? What about the world's biggest producer of environmentally harmful gasses -- China?

Steven Wojtal, professor of geology, Oberlin College

Roger Pielke, Jr, professor of environmental studies, University of Colorado

J. Craig Jenkins, Director, Mershon Center for International Security Studies, The Ohio State University