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Can Copenhagen Succeed?

Recent Science Supports Moving Much Faster to Curb Emissions

Intergovernmental Panel on Climate Change Chairman Rajendra Pachauri SOURCE: AP/KHAN TARIQ MIKKEL An analysis of the warming in store, and the warming we can hope to prevent, shows that proposed policies will have to stretch to put us in a climate “safe zone”— especially for developing nations. Above, Intergovernmental Panel on Climate Change Chairman Rajendra Pachauri.

Copenhagen, Denmark—Among the many stories emerging during the past two weeks here at the 15th Conference of the Parties to the U.N.’s Framework Convention on Climate Change—a.k.a., “COP 15”—a major one has involved crowd control. The Bella Center, where key negotiations are set, has been thronged by tens of thousands of people. Although matters now seem to have calmed a bit, earlier in the week the lines for picking up media passes were many hours long and journalists were suffering, freezing, and then getting turned away. A clever article in New Scientist suggests the event organizers flunked Math 101 in their planning, but there’s another reason, too, for the chaos: All these people, all these activists and journalists and negotiators and observers, are crowding the building because they want to see something happen.

Something big.

There’s just one small problem. Over recent years, as scientists have continued to iterate their climate and economic models—attempting to factor human population changes, economic growth, and national policies into an exceedingly complex and contingent picture of the atmospheric and planetary future—a distressing theme has emerged. It is very possible that warming is now moving so fast that today’s politically viable policies simply can’t avert a serious risk of catastrophic climate impacts occurring, or suffice to keep climate change within a clear “safe zone.” In other words, whatever Copenhagen achieves, it may not be enough. That’s especially the case for low-lying island nations beset by sea level rise, and other developing countries whose calls for climate justice, and the strongest possible precautionary policies, have engendered much sympathy here.

To see the nature of the conundrum, consider the analyses provided by Climate Interactive, a consortium of scientists and modelers who have developed a very useful way of analyzing the science and policy nexus of the climate debate, which can otherwise seem like a confusing quicksand of information. The Climate Interactive model merges scientific projections of how bad global temperatures could be by the year 2100 with the expected impacts of various national and international policies upon those temperatures. As of the most recent analysis, the model presents the following information: On a business-as-usual trajectory, we can expect a cataclysmic 4.8° Celsius of warming by 2100. Meanwhile, the currently confirmed climate policies embraced by nations worldwide—without a Copenhagen agreement—only get us down to around 3.9°C.

So where do the current Copenhagen proposals fit in between these two markers? Well, that’s the real trick. The summit could always surprise us, but as one of the Climate Interactive collaborators, MIT’s John Sterman, recently observed to Andrew Revkin of the New York Times, “the negotiations must deliver the high end of current proposals and stretch beyond them, if the world is to have a reasonable chance of containing warming to below 2°C above pre-industrial levels, or the 1.5°C goal of many developing nations.”

It’s important to note the truly insidious way in which risk manifests itself in these discussions. Really, we don’t know how bad global warming is going to be in 2100; we only have estimates of the sensitivity of the climate to various carbon dioxide emission levels, surrounded by bars of uncertainty. But fundamentally, the climate system—and especially its potential feedbacks—is incompletely understood. So if all of our projections understate the climate sensitivity, there’s a risk of undershooting even with relatively strong policies, and still failing to reach a safe zone.

This line of thinking necessarily argues for ever-tougher, more precautionary policies—and runs smack into messy political realities. One is that the powerhouse countries at Copenhagen, such as China, India, and the United States, are setting 2°C as the target, and not something stronger, like 1.5°C. Another is that whatever approach heads of states agree upon at Copenhagen, getting the U.S. Congress to support such goals in legislation is something else altogether.

Yet at precisely this time, a growing movement argues that 2° Celsius—which corresponds to roughly 450 parts per million (ppm) of carbon dioxide in the atmosphere—simply isn’t “safe.” Famed NASA climate scientist James Hansen and the movement are pushing the boundaries of the conversation by calling for a return to levels of atmospheric carbon dioxide concentrations that we have already passed (we are currently at 390 parts per million), and that correspond to something more like 1.5°C. And in Copenhagen, a bloc of developing nations has also coalesced around this goal, citing the threats of submerged Pacific islands, a scorched Africa, and much else.

Certainly, not all scientists think the situation is as bad as Hansen does, although the UN Intergovernmental Panel on Climate Change Chairman Rajendra Pachauri has also opined in the past that 350 ppm is really the safe level. (Interestingly, Pachauri seemed unwilling to reiterate that view when asked at a press conference here today.) But in the end, picking a scientific winner in such a debate misses the point: The risk of being wrong ought to be too much to be tolerated when the planet itself is at stake. Precaution is really the only thing that makes any sense.

And that’s the anguishing thing about watching the Copenhagen climate negotiations evolve: If you really, really care about planetary risk avoidance, you can’t like the way things are going.

Chris Mooney is the author of several books, including The Republican War on Science and Unscientific America: How Scientific Illiteracy Threatens Our Future, co-authored by Sheril Kirshenbaum. He and Kirshenbaum blog at “The Intersection.”

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