Science & Technology

The Convenient Truth

No easy answers to climate change questions


In October, British Prime Minister Tony Blair called for "radical international measures" to curtail greenhouse-gas emissions, and fast. "We can't wait the five years it took to negotiate Kyoto," he said. Apparently, 2012 is too late. In hopes of taking stronger steps, however, many U.S. environmentalists want to defer any legislation until President Bush is out of office. Apparently 2007 and 2008 are too early. That gives us precisely three years—2009, 2010, and 2011—to save the planet.

All right, that was a cheap shot. I couldn't help myself. Something about the global-warming debate encourages overheated rhetoric. To listen to Blair, former Vice President Gore, and many other political figures and environmental activists, you would conclude that global warming is an onrushing cataclysm and that prevention requires all of us to take radical steps right away.

A fairer assessment would be many degrees cooler. It would hold that climate change is real and deserves action, but that the problem is nowhere near as overwhelming as the rhetoric commonly suggests, and the solutions nowhere near as difficult. As problems go, in fact, climate change appears to be one of the most convenient that humankind has ever faced.

Last month, the Intergovernmental Panel on Climate Change announced [PDF] that the Earth is definitely warming and that human emissions of greenhouse gases (principally carbon dioxide) are almost certainly an important cause. We have a problem. But what sort of problem?

A crisis, Blair says. "It is not in doubt," he said in October, "that if the science is right, the consequences for our planet are literally disastrous." He was commenting on a recent British government report (popularly known as the Stern Report) on the economic effects of warming. In The Baltimore Sun, Bryan Mignone, a science and technology fellow at the Brookings Institution, cites that report's conclusion with alarm: "The damage associated with warming under a 'do-nothing' policy is likely to be 5 percent to 20 percent of global gross domestic product, an outcome to which the word 'catastrophic' would seem to apply."

Not so fast. Other analyses come up with cost figures more like 3 percent of GDP, but leave that aside. Reanalyzing the Stern Report, Yale University economist William Nordhaus recently noted that a "high-damage" scenario might reduce global GDP by almost 14 percent in the year 2200. On the Stern Report's own assumptions, "This means that per capita consumption would grow from $7,800 today to only $81,000 in 2200," instead of $94,000 (in today's dollars). That's not good, but it hardly seems catastrophic.

The IPCC says that the world would continue to warm for decades even if all human greenhouse-gas emissions were to magically stop tomorrow, which of course they won't. In testimony last month before a House of Representatives panel, Kevin Trenberth of the National Center for Atmospheric Research said, "The 2007 IPCC report makes clear that even aggressive mitigation would yield benefits many decades in the future, and that no amount of mitigation can avoid significant climate change."

Carbon dioxide both accumulates and dissipates in the atmosphere very slowly. Because the stock of greenhouse gases already present in the atmosphere dwarfs any one year's emissions, and because any one year's emissions can be changed only slightly, stabilizing greenhouse gases is like turning an aircraft carrier, only much slower. Annual emissions might be stabilized toward midcentury, and atmospheric concentrations at some point after that; but sharp turns are impossible and short-term effects minuscule.

That would be cause for alarm in an emergency. And many people talk as if there were one. "We need to act soon, before we reach a tipping point," Sen. Barbara Boxer, D-Calif., said at a hearing in January. Echoing Blair (as is his wont), David Cameron, the leader of Britain's Conservative Party, recently told reporters that the "big question" is, "Are we going to act before it's too late?"

Actually, there is no "too late," because there is no particular CO2 target and no particular date by which it must be met. And there is no emergency. An emergency is a "now or never" situation, but climate change is a "now versus later" situation. Immediacy trades off against efficiency.

"What we do now makes a difference for the future," says Gerald Meehl, a senior scientist at the National Center for Atmospheric Research. "The longer we wait, the worse the problem gets." On the other hand, the more precipitously we act, the more we disrupt the economy. A coal-fired electric plant lasts 40 to 60 years; gradually replacing dirty old plants with clean new ones is much more efficient than abruptly decommissioning old plants and replacing them with—well, with nothing, because electric plants take years to build. Besides, the best carbon-cutting technologies are still in development. "We know from experience the length of time it takes to develop and implement new technologies in the electricity sector," says Revis James of the Electric Power Research Institute. "That's about 20 to 25 years."

This argues not for passivity, and not for delay, but for _gradualism_: setting up policies that will tighten the screws on greenhouse-gas emissions over the next few decades. The convenient truth about global warming, then, is that radicalism is as pointless as it is impractical. Slow-but-steady is not only the easiest approach; it is also the most effective.

Just as conveniently, the most efficient way to get started is also the simplest, albeit not the easiest politically: tax carbon emissions. "At around $30 per ton of CO2 over a 25-year horizon, experts seem to think this is the kind of price that will encourage the kind of technologies that are necessary," says Billy Pizer, an environmental economist at Resources for the Future, a Washington think tank. That would translate into an additional 27 cents or so on a gallon of gasoline and about a 20 percent increase in residential electricity bills (more like 34 percent for industrial users). Unpleasant, but hardly radical. Perfectly do-able, in fact.

Fortuitously, a carbon tax could also reduce the U.S. budget deficit and the geopolitical leverage of sinister "petrocracies" such as Iran, Russia, and Venezuela. Policy prescriptions don't come any more convenient than that.

Because significant warming is already baked into the cake (excuse the expression), climate change for at least the next 50 to 100 years will be a problem to be managed, not solved. Managing it will require mitigating whatever harms it causes: adaptation, in the standard parlance. This, too, turns out to be remarkably convenient. Few, if any, of the problems that climate change seems likely to exacerbate—flooding, storms, drought, tropical disease, habitat loss, extinction—are new or exotic. To the contrary, they are already front and center on the developmental and environmental agendas.

Roger Pielke Jr., a University of Colorado professor of environmental studies, points out that many communities around the world are already maladapted to their climates. (Just ask New Orleans.) In the 1990s, he notes, extreme weather events caused more than 300,000 deaths; malaria currently kills between 1 million and 2.6 million people a year. Climate change will affect those problems, but on the margins. Pielke cites a study finding that the global population at risk of malaria would double by 2080 without global warming; climate change increases malaria risk by a further 7 percent.

Climate change, then, is a reason to do more of what makes sense anyway: reduce coastal vulnerability and strengthen homes to minimize hurricane damage, improve public health and develop drugs to fight malaria, and so on. There is nothing radical about any of this. No rethinking of capitalism is required.

Given how neatly adaptation dovetails with the sustainability agenda, and given its immense potential to relieve whatever human suffering that global warming causes, one might think environmentalists would tout it to the skies. Some do, but many seem to believe that reducing harm distracts from the real job, which is to reduce emissions. In a blog post last year (at, an environmentalist named David Roberts made the point with startling candor. "In an ideal, abstract policy debate, sure, I'd say we should boost our attention to adaptation," he wrote. "But in the current political situation, I don't want to provide any ammunition for the moral cretins who are squirming frantically to avoid policies that might impact their corporate donors."

This is like denigrating HIV treatment and blocking condom distribution in order to discourage promiscuity. And it is every bit as callous and irresponsible. Where climate change is concerned, the truth—and this truth really is inconvenient, or at least sad—is that too many activists and politicians mistake panic for virtue.

© Copyright 2007 National Journal

Jonathan Rauch is a senior writer and columnist for National Journal and a frequent contributor to Reason. The article was originally published by National Journal.