The Center of the Warm

"My feeling is, it's indisputable that greenhouse gases have increased. Some of that increase, though not all, was caused by human activity." He says it's possible that changes in greenhouse gases will entail temperature changes. But using models to predict what those changes will be 50 or 100 years in the future is difficult--and risky.

After sorting through the confusion, then, the level of concern people afford greenhouse warming may turn out not to be a matter of science.

"It comes down to politics," Balling says. And talking to him at length makes it impossible not to wonder how his scientific attitudes may be affected by his personal and political attitudes. He voices concerns about how proposed remedies for global warming might profit developing countries at the expense of the United States. On the flip side, he wonders what a dramatic reduction in carbon-fuel use would do to nations that are not as far along in their development as is the U.S.

Whether one decides global warming is a serious or relatively minor threat also depends, at least in part, on values and personality: Is it arrogant to think that humans can throw off the atmospheric balance of the planet, putting ourselves and other species in jeopardy? Are we overestimating our own importance? How can we balance those suspicions against our knowledge that we may already have set off irreversible, undetected consequences?

In answer to those questions, scientists can offer probabilities, Balling says, but that's all.

And, he offers with a smile, learning the answer to one question sometimes raises five or six more.