Bill McKibben

I spent the last few nights of the recent Poznan climate conference sleeping in the By the Way youth hostel, an excellent accommodation filled with excellent young people who had done excellent work at the negotiations. After the final day of deliberations, many of these young people visited the doubtless excellent discotheques of Poznan, returning home beginning about 4 a.m. in various states of excited giddiness. This allowed those of us (well, the one of us) of a more elderly persuasion an excellent opportunity to lie awake, thinking over the events of the days just past. And what I kept thinking about was the old model of the universe, which held that the Earth was at the center.

This so-called “Ptolemaic Universe” seemed obvious — since our planet clearly stood still, and since the other planets rotated around it daily, it was pretty darned clear that we were the stationary middle. It’s true that attempts to map the slightly odd orbits of those planets — which at various points would “retrograde,” or turn backward — cast some doubt, but not enough to really shake anyone’s faith. The Greek astronomers invented all sorts of flourishes to make the orbital calculations work: deferents and epicycles, equants and eccentrics, little wheels within wheels that preserved the theory for a very long time, more than a thousand years — till finally Copernicus came along with some new data and blew the whole thing up.

In somewhat the same way, we’ve all agreed to suspend disbelief for a long time and keep pretending that the process to do something about global warming is working. The text of the developing treaty is stupendously complicated, with a thousand fixes to plug various leaks: how you count where the carbon will come from, and who will pay what to whom, and what about those forests, anyway? The debate is staggeringly dull, and incredibly hard to follow. Every once in a while, some expert or another will emerge to say that the European Union has backslid on its intermediate targets, or that the global financing facility needs to be reconstituted, or so on.

But the real problem with the whole process is that, for some time now, it has been out of phase with the science of global warming. It’s impossible to take the most recent science, and the real world that it describes, and square it with the model being put together at these endless Conferences of the Parties (last week was the 14th, and the rainy, raw, dreary Polish weather matched the mood). The most obvious way to state this would be: The Arctic has now melted, 50 years ahead of the schedule that scientists had predicted when these talks were in their infancy. What does that tell you?

The language of these negotiations is numbers, and so the less obvious but more pragmatically powerful way to state it is: These interminable talks are designed to build a machine that would halt the atmospheric concentration of carbon dioxide somewhere in the neighborhood of 450 to 550 parts per million. They’re so loaded with loopholes, and the timetables are so slow, that they probably wouldn’t accomplish even that, but that’s the goal. The theory is that the world we need is a 450 world, based on the science from five and 10 and 15 years ago.

But a year ago, our leading scientific authority on climate change, NASA’s James Hansen, said that was wrong. All the data that he and his team assembled suggested that 350 parts per million was the maximum possible if we wished to keep “a planet similar to that on which civilization developed, and to which life on earth is adapted.” They pointed to not just the Arctic melt, but the shocking thaw of sub-tropical glaciers, the shifting of monsoonal rain patterns, and the rapidly developing fear that Greenland and the West Antarctic could raise sea levels much more quickly than we’d previously imagined. They said — in the context of these talks — that the sun does not in fact revolve around the Earth.

If such a view grows to be accepted, the implications are enormous. We would have to move much more quickly — we’re already at 387 parts per million, i.e., too high — and we’d have to cut much more deeply. Hansen’s calculations show that you’d need to be done burning coal by 2030, and much sooner in the developed world, if you were going to keep enough carbon out of the atmosphere to allow the chance for forests and oceans to cycle CO2 out and someday return us to 350. In essence, a 350 world would demand emergency action.

Since change comes slowly, work on the treaty has continued little affected for the last year. But the new data was beginning to sink in. (I should note my own interest here — I’ve spent the last year helping to run, a global campaign designed to spread this news far and wide.) Early in these Polish talks, the Lesser Developed Countries and the small island nations started talking a lot about “survivability.” They’d begun to figure out that following the negotiating script meant they’d soon be hauling their flags down from in front of the U.N. because their nations would have disappeared beneath rising seas or spreading deserts. This “survivability,” they said, corresponded with “350.”

And then, on the last day of the talks, Al Gore gave his speech, which drew everyone into the main conference hall. It was a good talk, but by far the longest and loudest applause came when he formally announced the new reality. “Even a goal of 450 parts per million, which seems so difficult today, is inadequate,” he said, adding that we “need to toughen that goal to 350 parts per million.” People erupted — probably not the Chinese and American delegations, and definitely not the Saudis and the Russians, but all the people who’d spent the last few years struggling with the idea that their work was getting increasingly off-the-point. It was a way of saying: We’ve been engaged in saving the treaty, not saving the world — and we’d rather save the world.

Given the momentum of the talks, they will drag on — nations have February deadlines for submitting responses to drafts, and new meetings in March and June, and everything points toward Copenhagen next December, where a final pact is supposed to be signed. But it’s hard to see now how that’s going to happen. Both Hansen, the leading scientific authority on climate change, and Gore, the leading political voice, have endorsed the idea of 350 as the only rational target. They’ve said the world circles the sun. Now we have to proceed on that understanding. It won’t be easy — “political reality” says it’s impossible. But political reality is easier to change than scientific reality. Since we can’t change the laws of physics, we’re going to have to try and change the laws of man.