U.S. Top Scientist: World Must Act Now to Reverse Climate Change

“The world needs ultimately to completely decarbonize,” says John Holdren, Obama’s science advisor. Here’s what he says about why we need to do it—and whether we can.

Read the complete article:
http://news.nationalgeographic.com/2015/12/151207-climate-change-holdren-white-house-science-paris/