Obama's Climate Deal in Beijing Makes a Global Agreement in Paris Likelier

When Presidents Barack Obama and Xi Jinping announced a pact on Nov. 11 to control their nations’ pollution, they answered long-standing calls from other countries for leadership in global warming diplomacy. Obama pledged that the U.S. will reduce its greenhouse gas emissions to at least 26 percent below its 2005 levels by 2025. China said it expects its emissions to peak by 2030, and it will increase the share of power produced from noncarbon sources such as nuclear and solar to 20 percent. Critics were quick to call their actions insufficient or superficial, but the move signaled each nation’s commitment to steps they’ve already taken on their own—and trust that each will continue to make progress.

Both leaders had more than their own emissions in mind. On Dec. 1, diplomats from all over the planet will gather in Lima, Peru, to discuss a comprehensive United Nations greenhouse gas reduction pact expected to be reached at a summit in Paris at the end of 2015. The negotiators will consider everything from minor technicalities to the biggest questions: Is there an outer acceptable limit for overall greenhouse gas pollution? Who will determine whether countries are sticking to their emissions-reduction promises, and how will the ones that miss their targets be punished? How much financial support will developing countries need to make the switch to clean energy sources?