The Volokh Conspiracy - The Phanerozoic Debate:

Today's NYT has a very informative and balanced story on the scientific debate over the relationship between carbon dioxide levels and global termperatures during the Phanerozoic era (roughly 550 million years ago to the present). One thing William Broad does particularly well in the story (and he was given ample space by his editors in which to do this) is to identify precisely where paleoclimatologists and geologists agree and disagree — something much popular reporting on climate science fails to do. It also points out the potential relevance of this dispute for contemporary climate change policy discussions. Here is a taste:

In recent years, scientists have made sizable gains in what was once considered an impossible art — reconstructing the history of Earth's atmosphere back into the dim past. They can now peer across more than a half billion years. . . .

The discoveries have stirred a little-known dispute that, if resolved, could have major implications. At issue is whether the findings back or undermine the prevailing view on global warming. One side foresees a looming crisis of planetary heating; the other, temperature increases that would be more nuisance than catastrophe.

Perhaps surprisingly, both hail from the same camp: scientists who study the big picture of Earth's past, including geologists and paleoclimatologists. . . .

the experts who peer back millions of years, though they may debate what their work means, do agree on the relevance of their findings. They also agree that the eon known as the Phanerozoic, a lengthy span from the present to 550 million years ago, the dawn of complex life, typically bore concentrations of carbon dioxide that were up to 18 times the levels present in the short reign of Homo sapiens. . . .

Where the specialists clash is on what the evidence means for the idea that industrial civilization and the burning of fossil fuels are the main culprits in climate change.

The story also notes that as paleoclimatic research becomes more relevant to policy debates, politics rears its ugly head.

Skeptics say CO2 crusaders simply find the Phanerozoic data embarrassing and irreconcilable with public alarms. "People come to me and say, 'Stop talking like this, you're hurting the cause,' " said Dr. Giegengack of Penn.

Those interested in climate policy should read the whole thing.

	[Jonathan Adler, November 7, 2006 at 1:02pm] Trackbacks The Phanerozoic Debate: Today's NYT has a very informative and balanced story on the scientific debate over the relationship between carbon dioxide levels and global termperatures during the Phanerozoic era (roughly 550 million years ago to the present). One thing William Broad does particularly well in the story (and he was given ample space by his editors in which to do this) is to identify precisely where paleoclimatologists and geologists agree and disagree — something much popular reporting on climate science fails to do. It also points out the potential relevance of this dispute for contemporary climate change policy discussions. Here is a taste: In recent years, scientists have made sizable gains in what was once considered an impossible art — reconstructing the history of Earth's atmosphere back into the dim past. They can now peer across more than a half billion years. . . . The discoveries have stirred a little-known dispute that, if resolved, could have major implications. At issue is whether the findings back or undermine the prevailing view on global warming. One side foresees a looming crisis of planetary heating; the other, temperature increases that would be more nuisance than catastrophe. Perhaps surprisingly, both hail from the same camp: scientists who study the big picture of Earth's past, including geologists and paleoclimatologists. . . . the experts who peer back millions of years, though they may debate what their work means, do agree on the relevance of their findings. They also agree that the eon known as the Phanerozoic, a lengthy span from the present to 550 million years ago, the dawn of complex life, typically bore concentrations of carbon dioxide that were up to 18 times the levels present in the short reign of Homo sapiens. . . . Where the specialists clash is on what the evidence means for the idea that industrial civilization and the burning of fossil fuels are the main culprits in climate change. The story also notes that as paleoclimatic research becomes more relevant to policy debates, politics rears its ugly head. Skeptics say CO2 crusaders simply find the Phanerozoic data embarrassing and irreconcilable with public alarms. "People come to me and say, 'Stop talking like this, you're hurting the cause,' " said Dr. Giegengack of Penn. Those interested in climate policy should read the whole thing.