Early drafts of the Intergovernmental Panel on Climate Change's next report were leaked online yesterday.
The report is due to come out in four parts, beginning in September 2013. But draft chapters from the IPCC's Working Group I, which analyzes the science of climate change, were posted last night at StopGreenSuicide.com, a website created by climate skeptic Alec Rawls.
Rawls, who says he dropped out of Stanford University's doctoral program in economics to pursue interests in "moral theory and constitutional law," is one of several hundred "expert reviewers" who volunteered to vet the Working Group I draft, part of the U.N. climate panel's extensive editing process.
"I believe the leaking of this draft is entirely legal, that the taxpayer funded report is properly in the public domain under the Freedom of Information Act, and that making it available to the public is in any case protected by established legal and ethical standards," Rawls wrote on the website yesterday.
In a statement released this morning, the IPCC said it was investigating the matter.
"Material appearing to be the draft of an Intergovernmental Panel on Climate Change (IPCC) report has been published on several websites," the statement said. "The IPCC is looking into this and will issue a more detailed statement later."
The leaked drafts, part of the IPCC's fifth major assessment of climate change, say the evidence that underpinned the group's 2007 report "has further strengthened."
The Nobel Prize-winning panel's 2007 report "concluded that warming of the climate system is unequivocal," a leaked summary of its latest analysis says. "New observations, longer data sets, and more paleoclimate information give further support for this conclusion. Confidence is stronger that many changes, that are observed consistently across components of the climate system, are significant, unusual or unprecedented on time scales of decades to many hundreds of thousands of years."
The report says there is a more than 95 percent chance that human activities have caused "more than half" of the increase in global surface temperature since the 1950s, and there is "high confidence that this has caused large-scale changes" in the ocean, snow and ice, and sea level since the second half of the 20th century.
Still, skeptics were quick to argue that the new report undercuts the IPCC's earlier work, pinning their analysis on a few sentences in the draft report's discussion of the sun's influence on climate change.
"IPCC AR5 draft leaked, contains game-changing admission of enhanced solar forcing," read the headline on a popular skeptic blog, "Watts Up With That?"
But several climate scientists said skeptics were misinterpreting the leaked drafts' conclusions.
"Mountains from molehill," Pacific Institute President Peter Gleick wrote on Twitter. "Out of context, old rejected wording. But oooh, secrets!"
NASA climate scientist Gavin Schmidt, also writing on Twitter, cautioned that "ppl shouldn't think that a line from SOD" -- second-order draft -- "is new consensus."
Many revisions still to come
Researchers were also quick to note that the leaked analysis was still preliminary and very likely to change before it is officially released next fall.
The analysis is due to undergo several additional rounds of editing over the next several months.
More than 250 scientists, working as coordinating lead authors, authors and review editors, put together the Working Group I draft.