"Some of the stories that gripped our attention in 2014 will probably be forgotten in a few years — if not a few weeks. But there's one story that President Obama argues we'll be living with for decades to come.
"There's one issue that will define the contours of this century more dramatically than any other. And that is the urgent and growing threat of a changing climate," he said in September, addressing the United Nations Climate Change Summit.
Even as Obama struggled with other big challenges this year, climate was one area where he managed to get some traction."