Paris Deal Would Herald an Important First Step on Climate Change - New York Times

PARIS President Obama and more than 100 world leaders will convene with thousands of diplomats on Monday on the outskirts of Paris to open two weeks of intense negotiations aimed at forging an accord that could begin to avert the most devastating effects of global warming and redefine the economy of the 21st century.

Here is a guide to what is at stake. If the talks fail as they did in two previous attempts to achieve such a deal then nations will continue on a trajectory that scientists say locks the planet into a future of rising sea levels, more frequent floods, worsening droughts, food and water shortages, destructive hurricanes and other catastrophic events.

Recent scie