Washington Post: Scientists around the globe have rejected their main arguments — that the climate isn’t clearly warming, that humans aren’t responsible for it, or that the whole thing doesn’t amount to a problem. Public opinion has also shifted and even Exxon Mobil talks about greenhouse gases. But this spring, it’s been obvious: Doubt is not dead. In fact, as Congress considers placing a national limit on emissions, Washington’s climate skeptics have been louder than usual — and they’ve …