Cause for Optimism at the UN Climate Talks in Lima, Peru?

This year's global temperatures will have been the highest since records began in 1880. Against that background, almost 200 nations are meeting in Peru, establishing strategy for another global climate-change summit next year in Paris. They got a recent boost when the US and China made an announcement on cutting carbon. We look at the objectives and the chance for success with former US Senator Tim Wirth, the top international climate negotiator for the Clinton Administration and now Vice Chairman of the United Nations Foundation, and Steven Cohen, Executive Director of Columbia University's Earth Institute and a Professor in the School of International and Public Affairs.

Thanks to Sasa Woodruff for production assistance.