National Geographic: Behind all the fanfare around this week's UN Climate Summit, which will bring 120 heads of state to New York on Tuesday, looms one big question: Will the nations of the world agree on a path to avoid the most dangerous consequences of climate change, such as dramatic sea-level rise and extreme droughts and storms?
The answer will not come during the official summit. This week's event is not a negotiating session for the next international agreement; that will happen in December 2015, when countries...