New York Times: The last-minute deal at the United Nations Climate Conference in Warsaw keeps hopes for a comprehensive successor agreement to the 1997 Kyoto protocol alive. But let us be clear: Much more decisive action will be needed if we are to stand any chance at fending off the dangers of climate change. We now have just one more shot, next year in Peru, to make more substantive progress toward a successor agreement before the crucial 2015 Paris conference. Even before then, it will be crucial for governments...