By James Van Nostrand at Yale Environment 360
By Joschka Fischer in Project Syndicate
By Alex Halperin in California Sunday
By George Dohrmann and Finlay Mackay at Huffington Post Highline
By Tim Flacke, Leigh Phillips, Mae Watson Grote, Jose Quinonez, Margaret Libby and Cathie Mahon at the Aspen Institute
The Aspen Institute is an educational and policy studies organization based in Washington, D.C.