Global Warming: Get Used To It

The most inconvenient truth about global warming is that we cannot stop it. Please don't mistake me for a skeptic. I'm fully persuaded by the evidence that climate change is real and serious. Of the 12 hottest years on record, 11 have occurred since 1995. Temperatures have risen by 0.74 degrees Celsius over the past century. (If that seems small, keep in mind that the difference in temperature between the ice age and now is about 5 degrees C.) And human activity appears to be one important cause. The concentration of greenhouse gases in the atmosphere has risen dramatically since the industrial revolution. Methane has doubled and carbon-dioxide levels are up 30 percent since 1750. The projections going forward are highly plausible scientific estimations. The recent report from the Intergovernmental Panel on Climate Change predicts that by 2100, temperatures will have risen by somewhere between 1.1 and 6.4 degrees, and as a result, sea levels will rise by 18 to 59 centimeters. The trouble is, if you accept all these facts and theories about global warming, it is difficult to see how any human response launched today can avert it.

The gases that are warming the Earth have built up over hundreds of years. They do not disappear or dissipate easily. Even if the world adopted the most far-reaching plans to combat climate change, most scientists agree that the concentration of greenhouse gases will continue to rise for the next few decades. In other words, global warming is already baked into Earth's future.

Scientists estimate that simply to keep greenhouse gases at their current levels, we would need to slash carbon-dioxide emissions by 60 percent. Given current and foreseeable technology, that would require cutting back on industrial activity across the globe on a scale that would make the Great Depression look very small. In fact, the future will almost certainly involve substantially greater emissions of CO2. Most studies predict that the world will double its consumption of energy by 2050. Since much of that growth in consumption will take place in China and India, it will involve the burning of fossil fuels.

Between them, these two countries are currently building 650 coal-fired power plants. The combined CO2 emissions of these new plants is five times the total savings of the Kyoto accords--that is, if the Kyoto targets were being adhered to by Western countries, which they are not. Even under the most optimistic scenarios the industrialized world will continue to burn substantial amounts of coal and oil.

I state these facts plainly not to induce fatalism or complacency. It's scandalous that we're not weaning ourselves off dirty fuels. Perfecting just two new (and almost workable) technologies--clean coal and hybrid cars--would be a giant leap forward. We could be experimenting with hundreds more technologies and techniques. But even so, the Earth would still warm substantially over the next few decades. So in addition to our efforts to prevent and mitigate climate change, we need to employ another strategy--adaptation.

No one likes to talk about adapting to global warming because it seems defeatist. But the result is that, as we debate the meta-theories about global warming, we're increasingly unprepared to deal with its consequences. Whether or not CO2 emissions are triggering certain reactions in the atmosphere, we can see that sea levels are rising. What are we going to do about it?

In an intelligent, practical speech last September, the president of the British Association for the Advancement of Science, Frances Cairncross, urged that we begin such a discussion. "We need to think about policies that prepare for a hotter, drier world, especially in poor countries," she said. "That may involve, for instance, developing new crops, constructing flood defenses, setting different building regulations or banning building close to sea level." She points out that adaptation programs could move forward fast. Unlike plans to slow down global warming, which require massive and simultaneous international efforts, adaptation strategies can be pursued by individual countries, states, cities and localities.

Three years ago the Pew Foundation sponsored an excellent study, "Coping With Global Climate Change," which focused on the role of adaptation. The report found that moving in this direction would be costly and fraught with uncertainty and error. Yet, the authors point out, humankind's long history has shown it's possible; we have adapted as the environment around us has changed. The costs of relocating seaside communities are extremely high, but they will be even higher if we wait 20 years. The most important conclusion of the Pew study was that early planning is far more effective than managing the consequences of a breakdown. In other words, strengthening the levees in New Orleans costs much, much less than rebuilding the city.

Many environmental advocates fear that talking about coping with global warming will hamper efforts to slow it down. In fact, we have no alternative but to do both. Mitigation and adaptation complement each other. In both cases, the crucial need is to stop talking and start acting.