Peer-to-Peer Review: How 'Climategate' Marks the Maturing of a New Science Movement, Part I

Please click for Part II and Part III.

How a tiny blog and a collective of climate enthusiasts broke the biggest story in the history of global warming science – but not without a gatekeeper of the climate establishment trying to halt its proliferation.

It was triggered at the most unlikely of places. Not in the pages of a prominent science publication, or by an experienced muckraker. It was triggered at a tiny blog – a bit down the list of popular skeptic sites. With a small group of followers, a blog of this size could only start a media firestorm if seeded with just the right morsel of information, and found by just the right people. Yet it was at this location that the most lethal weapon against the global warming establishment was unleashed.

The blog was the Air Vent. The information was a link to a Russian server that contained 61 MB of files now known as Climategate. Within two weeks of the file’s introduction, the story appeared on 28,400,000 web pages.

Not entirely the “death of global warming” as many have claimed – what happened with Climategate is much more nuanced and exponentially more interesting than the headlines convey. What was triggered at this blog was the death of unconditional trust in the scientific peer review process, and the maturing of a new movement – that of peer-to-peer review.

This development may horrify the old guard, but peer-to-peer review was just what forced the release of the Climategate files – and as a consequence revealed the uncertainty of the science and the co-opting of the process that legitimizes global warming research. It was a collective of climate blogs, centered on the work of Stephen McIntyre and Ross McKitrick, which applied the pressure. With moderators and blog commenters that include engineers, PhDs, statistics whizzes, mathematic experts, software developers, and weather specialists – the label flat-earthers, as many of their opponents have attempted to brand them, seems as fitting as tagging Lady Gaga with the label demure.

This peer-to-peer review network is the group that applied the pressure and then helped authenticate and proliferate the story.

Now, as expected, the virtual organism that is the global warming establishment resisted release of the weapon. At the first appearance of the Climategate files, which contained a plethora of emails and documents from the University of East Anglia’s Climate Research Unit, the virtual organism moved to halt their promulgation. Early on, a few of the emails were posted on Lucia Liljegren’s skeptic blog The Blackboard. Shortly after the post, Lucia, a PhD and specialist in fluid mechanics, received an email from prominent climatologist Gavin Schmidt from the NASA Goddard Institute for Space Studies (GISS). It said in part, “[A] word to the wise… I don’t think that bloggers are shielded under any press shield laws and so, if I were you, I would not post any content, nor allow anyone else to do so.”

In response to my inquiry about his email, Schmidt posited, “I was initially concerned that she might be in legal jeopardy in posting the stolen emails.” Gavin Schmidt was included in over 120 of the leaked correspondence.

Gavin_SchmidtGavin Schmidt

When asked if she thought the Climategate documents were a big deal at first sight, Lucia responded, “Yes. In fact, I was even more sure after Gavin [Schmidt] sent me his note.”

Remember these names: Steven Mosher, Steve McIntyre, Ross McKitrick, Jeff “Id” Condon, Lucia Liljegren, and Anthony Watts. These, and their community of blog commenters, are the global warming contrarians that formed the peer-to-peer review network and helped bring chaos to Copenhagen – critically wounding the prospects of cap-and-trade legislation in the process. One may have even played the instrumental role of first placing the leaked files on the Internet.

This group can be thought of as the first cousins to Andrew Breitbart’s collective of BIG websites – obsessively curious, grassroots investigators that provide vision to the establishment’s blind eye. Peer-to-peer review is the scientific version of the undernews.

To fully understand how this amorphous body came about, one has to press rewind – back to the introduction of the now famous “hockey stick” graph, and how this iconic image inadvertently gave birth to this group.


On October 14, 1998, Michael Mann, Raymond Bradley, and Malcolm Hughes, also known as Mann et al (1999), penned a paper entitled Northern Hemisphere Temperatures During the Past Millennium: Inferences, Uncertainties, and Limitations and submitted the study to the scientific journal Geophysical Research Letters (GRL). Given the acknowledged uncertainties and limitations expressed in the title, it is hard to believe that the graph showcased in the paper would later become the poster child of certainty for a scientific consensus on global warming – but it would become just that. The paper, an extension of a study published earlier that year in Nature magazine, included a reconstruction of global temperature variation over many centuries.

Part of the science of reconstruction claims that tree rings viewed in the cross-section of specific trees can be used to infer temperatures in the past. Subscribers to trees as temperature proxies believe that they provide a picture of past temperatures at times when thermometers were not present. The paper was published by GRL in 1999, and included the first hockey stick that stretched back to 1000 AD.


It is hard to overestimate the influence that this iconic image has had on the discourse over anthropogenic global warming, or temperature increases due to human emissions of CO2. From its introduction, the hockey stick graph, named for its shape resembling Wayne Gretsky’s weapon of choice, was seen as compelling evidence in the case for man induced global warming. The graph showed a relatively stable temperature trend over the past 1000 years, until about the 1900s, where the graph takes a turn upwards, followed by another dramatic turn sharply upwards at around 1960 through the time of the publication of the article.

What was alarming about this graph was that the up trend coincided quite closely to the beginning of the industrial revolution, widely thought to start at about 1850. If true, the graph’s temperature increase could be tied to the introduction of carbon dioxide emissions – pointing to man and machine steering the earth toward a collision course with the apocalypse. Theories of man-induced climate change had been around long before Mann et al, but their graph gave the effect of italicizing, underlining, and boldfacing the problem of global warming.


The utility of the hockey stick graph to convey this alarming belief was quickly realized, with a variation of the graph appearing on the front cover of a World Meteorological Organization report entitled WMO Statement on the Status of the Global Climate in 1999 (above). This version of the graph included temperature reconstructions of three different groups of climate scientists, including Michael Mann, as well as Phil Jones and Keith Briffa, the latter two both from the University of East Anglia’s Climate Research Unit – the university where the Climategate files originated. This graph was even more compelling than the Mann et al (1999) hockey stick because it provided a graphical scientific consensus of man-induced global temperature increase.

Michael_MannMichael Mann

Now, the WMO’s 1999 report was not just any obscure scientific climate audit. The World Meteorological Organization is one of the founders of the Intergovernmental Panel on Climate Change (IPCC) – the very body that is tasked with evaluating the risk of climate change caused by human activity. The inclusion of the hockey stick on the front cover was an indication that the graph would also be highlighted in the gold standard of global warming reports – the IPCC’s 2001 Third Assessment Report (IPCC TAR). The IPCC TAR is the document that provides governments with policy prescriptions to mitigate the effects of global warming.

The indication proved to be true, with the hockey stick graph being highlighted in not one, not two, but six different places throughout the report. Again, a scientific consensus was implied – providing a nice tidy story.

Its inclusion cemented the hockey stick as the iconic image for proponents of man-induced climate change. The graphs colorful and prominent display, in a sense, incited environmentalists to enlist with the camp of urgent action, and even inspired Al Gore to include a variation of the stick in his Oscar-Awarded documentary “An Inconvenient Truth.”

With its big screen debut, the hockey stick had pierced pop culture. It was now big time.

(More to come.)


Please let us know if you're having issues with commenting.