Police Inquiry Prompts New Speculation on Who Leaked Climate-Change E-Mails

The original e-mails, released in 2009 on the eve of a high-stakes United Nations climate conference in Copenhagen, sowed doubts about the scientists’ research and integrity and galvanized skeptics who challenge the scientific consensus that global warming is under way. It set off six separate official inquiries, all of which cleared the researchers of scientific misconduct.

Then the controversy receded. Yet recently, speculation about the identity of the person who leaked the messages has surged with the release of new e-mails and signs that a police inquiry is under way in Britain.

In November, just before another major international climate conference opened, this time in Durban, South Africa, another round of e-mails between the scientists were distributed online. Like those released in 2009, they were part of a trove taken from a computer server at the Climate Research Unit of the University of East Anglia in England; as before, the e-mail hijacker alerted the public to the e-mails in comments posted on various blogs.

But November’s leaker left additional clues behind as well. Not much — an encrypted file and a note ending in what seemed to be a taunt — but enough to revive fervent speculation about what sort of person might be behind the stunt.

The note, somewhat cryptic, seemed to suggest that efforts to fight global warming siphoned money from worthy causes like fighting poverty. “Every day nearly 16,000 children die from hunger and related causes,” it said.

Then the note’s author seemed to dangle a challenge for hackers and programmers, saying that even though he was releasing 5,000 e-mails, “The rest, some 220,000, are encrypted for various reasons.”

“We are not planning to publicly release the pass phrase,” the note added coyly.

The stunt was enough to jump-start a police investigation that had long seemed dormant.

In December, citing a request from British law enforcement, the Justice Department asked that Automattic, the parent company of the blog host WordPress.com, preserve three days of digital logs for three blogs where the links to the latest e-mails first appeared. In a raid in Leeds, England, the police also confiscated laptops from the home of one blogger; he says the police have told him that he is not a suspect.

The note, the encrypted file and the fresh signs of police interest have inspired musings on both sides of the climate divide.

Kert Davies, the research director of the environmental group Greenpeace, suggested that the note was “a strong clue on the predisposition of the hacker.”

“It smells a lot like a certain quadrant of the denier community,” he said. “They pretend to be concerned that we are impeding development in poor countries. Only certain think tanks think that way and play that way” — mostly in Europe, he said.

Some have noted that in 2009, the online trickster used the initials R.C. and linked to a zip file named “FOI2009,” an apparent reference to Freedom of Information statutes in both Britain and the United States.

(Much of the criticism of climate scientists at the University of East Anglia centered on delays in responding to Freedom of Information requests, usually from climate skeptics, for access to all of their data and even their e-mails.)

This time, he signed his blog comments simply as “FOIA,” a common nickname for the leaker in online discussions of the e-mail affair.

Myron Ebell, director of energy and global warming policy at the Competitive Enterprise Institute in Washington and a frequent spokesman for climate change skeptics, said the encryption of the file had challenged his thinking on FOIA’s identity.

Previously, he said, he had assumed the leaker was an employee of the University of East Anglia who had been troubled by the denial of requests for the prompt public release of scientists’ full data and e-mails under Britain’s Freedom of Information Act.

But a principled commitment to open information is not in keeping with an encrypted file, Mr. Ebell said. So he suspects a different kind of intelligence is at work.

“It is very suggestive of someone who has thought through how to cause the con men at the C.R.U. the maximum possible anxiety,” he said, referring to the Climate Research Unit at the University of East Anglia. “It is like knowing your building has a bomb in it that could be detonated at any time.”

Yet Brendan DeMelle, executive director of DeSmogBlog, a Web site devoted to debunking what it describes as misinformation campaigns by deniers of climate change, suggests that the encrypted file is merely a desperate attempt to distract people from the fact that the scientists were vindicated.

“It is sort of bait,” he said. “It raises questions on what else is out there. In the end, uncertainty is their product.”

The three blogs where comments were submitted alerting the online community to the new e-mails are all known for their critiques of the work of climate scientists.

Asked if he had any clues to the leaker’s identity, Steve McIntyre, the Canadian blogger who runs climateaudit.org, said, “I don’t know who it is and I can’t think of any reason why anyone would think I did.” He has not been contacted by any law enforcement entity, he said.

Roger Tattersall, a Web content manager at the University of Leeds who had two laptops confiscated by British police constables last month, did not shed light on the mystery, either. “I do not wish to issue a denial, because it invites the assumption that there is an accusation or suspicion,” said Mr. Tattersall, who authors a blog known as Tallbloke’s Talkshop. He added, “The police have stated that I am not a suspect.”

In an e-mail provided by Mr. Tattersall to The New York Times, his lawyer emphasized that his client would have cooperated with the police without their needing a search warrant. The Norfolk constabulary, which carried out the raids, refused to comment on the raid or any investigation.

Jeff Condon, the author of a blog called The Air Vent, said he had no idea who posted the links to the e-mails on his blog.

Yet he said he found it interesting that for the most part, the phantom posted links on blogs like his own, where many of those who commented seem conversant in technology.

“Most of my readers are college graduates, 50 percent have Ph.Ds,” he said. “This is the kind of people that the guy who dropped the links” sought to reach, he said.

Still, Mr. Condon said he did not believe that “FOIA” is a serious person. At times, he said, he has assumed that the leaker is a mischievous student.

“No adult with sensitive information would release it that way,” he said. “It’s pranklike behavior.”

Yet among scientists whose e-mails were released and whose research practices were then investigated, the signs that an investigation is afoot have revived hopes that the e-mail thief will ultimately be unmasked.

“It seems to me the authorities wouldn’t have acted without some actionable intelligence,” said Michael Mann, a scientist at Pennsylvania State University who specializes in climate modeling and whose messages came in for particular scrutiny in 2009. “They must know something that we don’t yet know.”