An Inconvenient Price

Economics is "the dismal science," in part because it puts a price tag on the pleasure of moralizing. This is pertinent to the crusade, often masquerading as journalism, aimed at hectoring developed nations into taking "strong" actions against global warming. For such nations (developing nations have more pressing priorities), the question, plainly put, is: How much are they willing to pay—in direct expenditures, forgone economic growth, inefficiencies and constricted freedom—in order to have a negligible effect on climate change?

Zealots say fighting global warming is a moral imperative, so cost-benefit analyses are immoral. Like our Manichaean president, they have a simple fixation: Are you with us or not? But in his book "Cool It: The Skeptical Environmentalist's Guide to Global Warming," the Danish economist Bjorn Lomborg suggests that global warming, although real, is not apt to be severe; that many of its consequences will be beneficial, and that the exorbitant costs of attempting to substantially curtail it would squander resources that, put to other uses, could have effects thousands of times more ameliorative. He offers cautionary calculations:

The warming that is reasonably projected might be problematic, although not devastating, for the much-fretted-about polar bears, but it will be beneficial for other species. The Arctic Climate Impact Assessment anticipates increasing species richness.

Global warming was blamed for 35,000 deaths in Europe's August 2003 heat wave. Cold, however, has caused 25,000 deaths a year recently in England and Wales—47,000 in each winter from 1998 to 2000. In Europe, cold kills more than seven times as many as heat does. Worldwide, moderate warming will, on balance, save more lives than it will cost—by a 9-to-1 ratio in China and India. So, if substantially cutting carbon dioxide reverses warming, that will mean a large net loss of life globally.

How cool do we want the world to be? As cool as it was when the Arctic ice pack extended so far south that Eskimos in kayaks landed in Scotland? Just cool enough to prevent the oceans from inundating us?

The U.N.'s 2007 report estimates that by 2100, sea levels will rise about a foot—as much as they have risen since 1860. That will mean a number of local problems, not a planetary crisis. More people now live near coasts (which is why hurricanes have become more costly; they have not become more frequent or violent), but protecting people and property from the sea would be far less costly than attempting to turn down the planet's thermostat.