So in the wake of news that the Arctic ice is melting faster than anyone expected, the UN climate summit is kicking off in New York today. It's true, nothing super-meaningful is going to come out of the conference—especially since President Bush has basically refused to attend, having decided to hold his own "summit" in Bali—but, as Matt Yglesias points out, the kabuki still serves a purpose, since it helps keep talks over how the world can best mitigate climate change moving in such a way that a new U.S. president could come into office in 2009 and, in theory, hit the ground running.

On a conference call last week with reporters, John Kerry and Tim Wirth—the main U.S. negotiator for the first Kyoto agreement—put the timeline in perspective. The Kyoto Protocol is set to expire in 2012. Kerry and Wirth estimated that it would take three years from the time that there's global agreement on a new treaty to actual ratification. So in order for there to be any chance of a new global treaty taking effect in 2012—and avoid having all the existing emission-reduction mechanisms in Europe and elsewhere come to a halt—the next U.S. president would, ideally, negotiate and get a new treaty agreed to by the end of 2009.

Kerry, for his part, seemed to think this would be insanely difficult but still doable: "If you have [a new president] who understands the nature of the challenge, who realizes the legitimacy of the crisis ... then I believe you can put experienced people in place and very rapidly move the United States," he said. "It'll be a push but we have no choice." The big question, though, is how effective the new treaty would actually be. Kerry also argued that, even though the last Kyoto agreement was nixed by the Senate 95-0, a new treaty that addressed concerns about China, India, and other developing countries could win the Senate's approval. We'll see. I'm mildly optimistic about Congress passing some sort of cap-and-trade system, less so about signing on to a global climate-change treaty in the near future. But I'd love to be wrong.

Note, too, that Kerry's scenario would depend on having a president who made global warming a top priority—higher than, say, health care or taxes. Unfortunately, that doesn't seem to be in the cards at this point in the campaign.