By David L. Brown
We all know the story: A certain desert-dwelling canine has its eye on an indigenous bird and goes to all kinds of extremes in an attempt to catch the avian speedster. This is, of course, the imaginary world of Wile E. Coyote and the Roadrunner.
Now a recurring episode in the on-going tale of the coyote and the bird is being used as a metaphor for the situation the human race may face if suspicions prove correct that the Earth is passing tipping points of warming and climate change that cannot be reversed. In the 13 October 2006 issue of SCIENCE magazine, (“Trying to Lasso Climate Uncertainty,” pgs. 243-244) environmental scientist Brian O’Neill, a staffer at the International Institute for Applied Systems Analysis ( IIASA) uses a metaphor from the cartoon series to make his point about all the factors we do not yet understand about the environment.
The classic scene to which he refers takes place when Wile E. Coyote, in hot pursuit of the Roadrunner, runs off the edge of a cliff. In violation of the laws of physics, the coyote stops in mid-air, not realizing that he is about to fall. Then, when he looks down he suddenly plummets toward the canyon floor, fading into the far distance. After a brief pause we see a little “puff” of dust to signal the end of his fall. Here is an illustration that reflects the lesson that Wile E. repeatedly fails to learn:
O’Neill fears that humanity may already be in a situation analogeous to that in which Wile E. Coyote finds himself after running off the cliff, but still unaware of his coming fall. According to the SCIENCE interview with O’Neill, an American climate scientist who works in the IIASA’s headquarters near Vienna, Austria:
A few weeks ago, Brian O’Neill hunkered down around a table with a dozen other climate scientists in Cape Town, South Africa, to talk about the future of the planet. It was no idle speculation: Whatever they agreed upon–they knew in advance–would have clout. They were hammering out the final draft of a chapter on research methods for the massive “Fourth Assessment” of the Intergovernmental Panel on Climate Change (IPCC). The product of 3 years of consensus-building among several hundred researchers from around the world, the IPCC report is the scientific bedrock on which policymakers will negotiate everything from carbon taxes to long-term greenhouse gas targets.
But for all its authority, the IPCC exercise left O’Neill with a nagging concern: What were they leaving out? “It’s important that we climate scientists speak with a single voice,” he said in an interview back in his office, high up in the attic of a former Habsburg palace outside Vienna. But “the extreme scenarios that tend to fall out of the IPCC process may be exactly the ones we should most worry about,” he says.
“Researchers desperately need a strategy for tackling climate uncertainties,” says O’Neill, who heads the IIASA’s Population and Climate Change (PCC) Program and is a co-leader of the Greenhouse Gas Initiative. He holds a Ph.D. in Earth Systems Science and an M.S. in Applied Science, both from New York University. He points out that one of the potential “cliffs” that climate scientists should learn more about is the potential for the Atlantic thermohaline conveyor system to stall or reverse, throwing northern and western Europe into the deep freeze. Scientists worry that global warming could abruptly change or even shut down the conveyor. The SCIENCE article continues:
The second big question to emerge from the IIASA sessions is how can we tell if mainstream research is headed in the wrong direction? O’Neill, Michael Oppenheimer, and Mort Webster, climate scientists at Princeton and the Massachusetts Institute of Technology in Cambridge, respectively, use the term “negative learning” to describe cases in which scientific consensus builds around the wrong model. “This is what happened with ozone,” says Oppenheimer. People believed that ozone’s key interactions are with other gases, until scientists realized that the critical reactions driving ozone depletion occur on the surfaces of airborne particles. With revised reaction rates, it was suddenly clear that the planet’s protective ozone layer was in much bigger trouble than had been thought. Oppenheimer proposes that scientists team up with philosophers and historians to find common signs of negative scientific learning. A search for such red flags could be built into climate science’s regular review process. And O’Neill says more funds should be set aside to explore hypotheses outside the mainstream.
You can read more about how the ozone problem continues to confound scientists in a post from earlier today by my associate Val Germann. Clearly, what we thought we knew about ozone is once again turning out to be wrong. Ominously, there is evidence of similar mis-calculations in many areas concerning the planet’s environment. For example, the SCIENCE article quoted another researcher, Michael Schlesinger, a climate scientist at the University of Illinois, who noted that polar ice sheets are melting more rapidly than anticipated, and some observers fear that this could lead to a catastrophic sea-level increase (Science, 24 March, p. 1698). “Things are happening right now with the ice sheets that were not predicted to happen until 2100,” Schlesinger says. “My worry is that we may have passed the window of opportunity where learning is still useful.”
Clearly, O’Neill is correct that we desperately need to learn more about the many intertwined factors that are acting to change our planet, and the data on which to make decisions about the future are often fuzzy to say the least. One of O’Neill’s focuses at IIASA is on the emerging industrialization of China and what effects we can expect to see in future years. The SCIENCE article reports:
Different predictions of how the country’s population will age and urbanize–and how carbon-emission policies will shape Chinese consumption–have an enormous effect on global climate change scenarios. But obtaining accurate demographic data has been difficult. With the help of a Chinese member of his new team, O’Neill has done an analysis revealing that the IPCC assumptions about China’s rate of urbanization and energy consumption could be off by a factor of 2.
So can we learn from the experience of Wile E. Coyote and stave off or mitigate the worst effects of climate change? In view of the many uncertainties, “negative learning,” and failure to follow up on alternative avenues of research, that remains very much to be seen. And if indeed we have already “run off the cliff,” there may be no alternative to metaphorically following the hapless coyote on his freefall to the desert floor below.
That would be no occasion for laughter, because the collapse and crash of the entire planetary environment would cause more than any comical little “poof” of dust, perhaps something more akin to the impact that ended the Cretaceous Era 65 million years ago. That event wrote finis to the Age of the Dinosaurs. Will the next event mark the end of human civilization? Stay tuned.