LONDON - E-mails stolen from climate scientists show they stonewalled skeptics and discussed hiding data - but the messages do not support claims that the science of global warming was faked, according to an exhaustive review by the Associated Press.
The 1,073 e-mails show that scientists harbored private doubts, however slight and fleeting, even as they told the world they were certain about climate change. However, the exchanges do not undercut the vast body of evidence showing that the world is warming because of man-made greenhouse-gas emissions.
The scientists were keenly aware of how their work would be viewed, and, just like politicians, went to great pains to shape their message. Sometimes, they sounded more like schoolyard taunts than scientific tenets.
The scientists were so convinced by their own science and so driven by a cause "that unless you're with them, you're against them," said Mark Frankel, director of scientific freedom, responsibility, and law at the American Association for the Advancement of Science. He also reviewed the communications.
Frankel saw "no evidence of falsification or fabrication of data, although concerns could be raised about some instances of very 'generous interpretations.' "
Some e-mails expressed doubts about the quality of individual temperature records or why models and data didn't quite match. Part of this is the normal give-and-take of research, but skeptics challenged how reliable certain data were.
The e-mails were stolen from the network server of the climate research unit at the University of East Anglia in southeast England, an influential source of climate science, and were posted online last month.
The Associated Press studied all of the e-mails for context, with five reporters reading and rereading them - about one million words in total.
One of the most disturbing elements suggests an effort to avoid sharing scientific data with skeptics. It is not clear whether any data were destroyed; two U.S. researchers denied it.
The e-mails show that several mainstream scientists repeatedly suggested keeping their research materials away from opponents who sought it under American and British public records law. That raises a science-ethics question because free access to data is important so others can repeat experiments as part of the scientific method. The University of East Anglia is investigating the blocking of information requests.
"I believe none of us should submit to these 'requests,' " declared the university's Keith Briffa. The center's chief, Phil Jones, wrote: "Data is covered by all the agreements we sign with people, so I will be hiding behind them."
When one skeptic kept filing FOI requests, Jones, who didn't return requests for comment, told another scientist, Michael Mann: "You can delete this attachment if you want. Keep this quiet also, but this is the person who is putting FOI requests for all e-mails Keith [Briffa] and Tim [Osborn] have written."
Mann, a researcher at Pennsylvania State University, told the Associated Press: "I didn't delete any e-mails as Phil asked me to. I don't believe anybody else did."
The e-mails also show how professional attacks turned very personal. When former London financial trader Douglas J. Keenan combed through the data used in a 1990 research paper Jones had cowritten, Keenan claimed to have found evidence of fakery by Jones' coauthor. Keenan threatened to have the FBI arrest University at Albany scientist Wei-Chyung Wang for fraud. (A university investigation later cleared him of wrongdoing.)
"I do now wish I'd never sent them the data after their FOIA request!" Jones wrote in June 2007.
In another case, after initially balking on releasing data to a skeptic because it was already public, Lawrence Livermore National Lab scientist Ben Santer wrote that he then opted to release everything the skeptic wanted - and more. Santer said in a phone interview that he and others are inundated by frivolous requests from skeptics that are designed to "tie-up government-funded scientists."
The e-mails also showed a stunning disdain for global-warming skeptics.
One scientist practically celebrates the news of the death of one critic, saying, "In an odd way this is cheering news!" Another bemoans that the only way to deal with skeptics is "continuing to publish quality work in quality journals (or calling in a Mafia hit)." And a third scientist said the next time he sees a certain skeptic at a scientific meeting, "I'll be tempted to beat the crap out of him. Very tempted."
And they compared contrarians to communist-baiting Sen. Joseph McCarthy and Somali pirates. They also called them out-and-out frauds.
Santer, who received death threats after his work on climate change in 1996, said Thursday: "I'm not surprised that things are said in the heat of the moment between professional colleagues. These things are taken out of context."
When the journal Climate Research published a skeptical study, Penn State scientist Mann discussed retribution this way: "Perhaps we should encourage our colleagues in the climate research community to no longer submit to, or cite papers in, this journal."
That skeptical study turned out to be partly funded by the American Petroleum Institute.
The most provocative e-mails are usually about one aspect of climate science: research from a decade ago that studied how warm or cold it was centuries ago through analysis of tree rings, ice cores and glacial melt. And most of those e-mails, which stretch from 1996 to last month, are from about a handful of scientists in dozens of e-mails.
As part of the AP review, summaries of the e-mails were sent to seven experts in research ethics, climate science and science policy.