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Controversial climate scientist Michael Mann, who helped raise global warming’s profile by representing temperatures as a rapidly escalating “hockey stick,” has filed a defamation lawsuit against skeptics at the National Review and the Competitive Enterprise Institute.

Mann said statements by the two organizations that compared him to convicted child molester Jerry Sandusky were offensive and defamatory, and called them the latest in a series of attacks he and other climate scientists have faced.

“Unsatisfied with their lacerations of his professional reputation, defendants have also maliciously attacked Dr. Mann’s personal reputation with the knowingly false comparison to a child molester,” the complaint reads.

Mann described the comments as one in a chain of attacks he has faced for his research into the effects of carbon dioxide -- and mankind -- on the climate.

'Defendants have also maliciously attacked Dr. Mann’s personal reputation with the knowingly false comparison to a child molester.' — the case of Dr. Michael E. Mann vs. The National Review and The Competitive Enterprise Institute

“There is a larger context for this latest development, namely the onslaught of dishonest and libelous attacks that climate scientists have endured for years by dishonest front groups seeking to discredit the case for concern over climate change,” Mann wrote on his Facebook page, where he had earlier announced the lawsuit.

The case centers on a sentence in a July 13 blog post that called Mann “the Jerry Sandusky of climate science, except that instead of molesting children, he has molested and tortured data in the service of politicized science.”

Written by CEI’s space technology and policy analyst and reposted by the conservative National Review website, those words were eventually removed, said Sam Kazman, general counsel at CEI.

“That was partly premised on the fact that Mann himself had spent time at Penn State,” Kazman told FoxNews.com. “Looking back at it after a few days, we decided it was somewhat inappropriate. But the piece itself is up there.”

But Kazman defended the larger post, which accused Penn State of whitewashing an investigation into Michael Mann to avoid negative publicity.

“Mann demanded retractions and apologies, and even though we had removed one or two sentences that involved the rhetoric, we thought the basic claims were substantially supported and declined to do anything more,” Kazman told FoxNews.com.

David Rivkin, lead counsel for the National Review, said the lawsuit was meant to silence critics.

“Michael Mann holds himself out as a twenty-first century man of science but with this lawsuit he shows that his thinking is medieval at best," Rivkin told FoxNews.com. "There is nothing enlightened about trying to use the courts and the libel laws to silence your critics."

"The First Amendment provides robust protections for speech about public figures and policy debates," he said. "We anticipate full and complete vindication that the Constitution protects these opinions."

Mann, a professor and director of the Earth System Science Center at Pennsylvania State University, is a climate scientist whose research has focused on global warming. Mann's seminal work was a 1998 climate study that showed a sharp, hockey-stick-shaped increase in the world's temperatures based on an analysis of age rings in trees. Despite ongoing criticism, the study formed the backbone of global warming theories -- until leaked e-mails from top climate scientists cast fresh doubt on Mann's methodology.

Mann has spent years battling back against those concerns, and what he described as an "onslaught of attacks."

John B. Williams, Mann's lawyer, did not immediately return FoxNews.com phone calls.

“There’s irony in a global warming proponent trying to freeze discussion of this issue,” Kazman told FoxNews.com.