Mainstream scientists say that this much carbon dioxide could warm the earth, on average, by 3 to 5 degrees Fahrenheit. By comparison, that is about half as much as it has warmed since the depths of the last ice age 18,000 to 20,000 years ago. A change of this magnitude would likely have widespread consequences for the world's climate, weather and human life. Their work is not expected to be finished for at least a year, and the Kyoto agreement still must be ratified by a sufficient number of countries after that. Dr. Ausubel predicts that this evolution will produce a carbon-free energy system by the end of the 21st century.
Analysts say the discrepancy is evidence that the economy is being decoupled from carbon.
The agency reported this month that the same is generally true in China, the biggest consumer and producer of coal in the world, where coal production has been reported to be dropping lately. It is said to run at 60 miles per gallon of gasoline in town, and 71 on the highway, and to travel 600 to 700 miles on a tank of gas. Other auto makers are also planning hybrids, which are being viewed as a transition, ultimately, to vehicles powered by hydrogen fuel cells that emit no carbon. And while auto companies are looking down that track, some of the world's biggest energy companies are looking to provide the appropriate fuels. Hydrogen, in particular, has attracted fresh interest.