In November 2009, an external user hacked the server at the Climate Research Unit (CRU) of the University of East Anglia and copied thousands of emails and documents, spanning 13 years of communication between CRU scientists[1]. The stolen content began appearing anonymously across the internet and the public, especially climate change skeptics, used the information against CRU scientists[2]. Climate change skeptics selected excerpts from the documents to substantiate claims that climate scientists are manipulating their data. This generated public debate on human-driven climate change. Given the publicity and numerous allegations filed against the CRU scientists, the origin, impacts, and professional ethics of the CRU email controversy warrant study. Although the CRU scientists were not found guilty of scientific misconduct by numerous scientific organizations, the language used in their routine communication suggests they value their reputations about advancement of scientific knowledge[3][4].

The Hubert Lamb Building, University of East Anglia, where the Climatic Research Unit is based

Unauthorized Access of Scientific DocumentsEdit

On November 20th, 2009, CRU employees reported a security breach in their server, where approximately 160 MB of data, with 1,073 emails and more than 3,000 documents, were copied by an unauthorized user three days prior to the reporting[5]. The police investigation described the incident as a “sophisticated and carefully orchestrated attack on the CRU’s data files, carried out remotely via the internet”[5]. Two days after the security breach, the data were published on a Russian server and then published on "The Air Vent", a blog supporting climate change skeptics’ viewpoints[6][7]. The stolen documents and emails appeared on the blog as an anonymous post with the following introduction: “We feel that climate science is, in the current situation, too important to be kept under wraps. We hereby release a random selection of correspondence, code and documents. Hopefully it will give some insight into the science and the people behind it. This is a limited time offer, download now”[6][7]. This statement suggests the intentions of the data hackers were to expose private information regarding climate scientists and leaves interpretation of the content to the audience. As this content obtain more public views, the story received media coverage, with newspapers publishing articles about the documents hours after the police reporting, and public allegations against the scientist appeared across the internet[2][7][8].

Content of DocumentsEdit

Below are transcripts the most controversial emails:[9][6]

From: Kevin Trenberth <> 
To: Michael Mann <>
Date: Wed, 12 Oct 2009 13:31:15 +0000 

Dear Mike, 
...The fact is that we can't account for the lack of warming at the moment and it is a travesty that we can't... Our observing system is inadequate.

The email describes short term temperature drops and the deficiency of current models to accurately predict these variations. Skeptics claimed this email is evidence scientists are hiding data contradicting climate change[10]. However, the email does not state the models are wrong or an intention to mislead; on the contrary, Kevin was discussing his previously published paper which explains the deficiencies and does not imply recent temperatures are unusual or contradictory.[11]

From: Phil Jones <> 
Date: Tue, 16 Nov 1999 13:31:15 +0000 

Dear Ray, Mike and Malcolm, 
...I've just completed Mike's Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) and from 1961 for Keith's to hide the decline. 

This email describes a published graph showing global temperatures over the last few centuries as estimated from tree ring patterns. The "decline" is a result of the well-established "tree ring divergence problem", which states temperature estimates from tree rings are fairly accurate before about 1960 and diverge drastically from direct temperature measurements after 1960.[12] Thus, the tree ring data shows a decline in temperature in the last few decades, while to actual temperatures increased. Phil Jones and Michael Mann, two CRU scientists, eliminated this problem by substituting measured data for the tree ring-derived data in the last portion of the graph, as shown in this modified version of the graph. While this manipulation of the graph is misleading because the different data sources are not fully explained, this technique is a legitimate attempt to reconcile two data sets, and there is no pure data fabrication.

From: Phil Jones <> 
To: "Michael E. Mann" <> 
Date: Thu Jul 8 16:30:16 2004 

... I can't see either of these papers being in the next IPCC report. Kevin and I will keep them out somehow - even if we have to redefine what the peer-review literature is ! 

This email is describing papers published by climate change skeptics.[9] Based the language in the email, Phil Jones was attempting exclude these reports from the final IPCC report by utilizing his influence as a prominent researcher. One paper was left out of early drafts of the report but included in the final version, where its findings were mostly dismissed. This attitude of relying on prestige to exclude the reporting of certain scientific works is disconcerting and does seem to be evidence of ethical conflicts within the CRU.

From: Phil Jones <> 
To:, Tom Wigley <> 
Date: Wed Dec 3 13:57:09 2008 
When the FOI requests began here, the FOI person said we had to abide by the requests. It took a couple of half hour sessions - one at a screen, to convince them otherwise showing them what CA [ClimateAudit] was all about. Once they became aware of the types of people we were dealing with, everyone at UEA (in the registry and in the Environmental Sciences school – the head of school and a few others) became very supportive. I've got to know the FOI person quite well and the Chief Librarian - who deals with appeals... 

This email shows CRU was deliberately rejecting Freedom of Information (FOI) requests. CRU employees were receiving many requests from group attempting to discredit their work, making their frustration understandable; although, refusing to make their data publicly available is ethically questionable[9].

Response from Scientific CommunityEdit

Six independent investigations conducted by official scientific organizations concluded there is insignificant information to convict the CRU scientists of scientific fraud[13][14][15][4][16]. The Pennsylvania State University conducted a three-part investigation on Dr. Michael E. Mann after the university received numerous allegations against Dr. Mann for research misconduct[13]. The investigation concluded “Dr. Mann did not engage in any actions that seriously deviated from accepted practices within the academic community”[13]. The National Science Foundation, a key funding source for Dr. Mann’s research, conducted an investigation on his published works and concluded “no direct evidence has been presented that indicates [Dr. Mann] fabricated the raw data used for his research”[16]. The University of East Anglia conducted two investigations on the CRU scientists after the emails received significant media attention and concluded the scientists committed no scientific wrongdoings: "On the specific allegations made against the behaviour of CRU scientists, we find that their rigour and honesty as scientists are not in doubt"[15]. The United Kingdom Parliament and the United States National Oceanic and Atmospheric Administration conducted independent investigations to conclude there is “no evidence of inappropriately manipulated data” in the works published by the CRU scientists[14][4].

Response from Climate SkepticsEdit

Climate change skeptics criticized CRU scientists by stating the emails show a lack of honesty and openness. Patrick J. Michaels, a climatologist skeptical of human-driven global warming, contends the CRU scientists were attempting to prevent his research from being published. “This shows these are people willing to bend rules and go after other people’s reputations in very serious ways,” he said referring to the email from Phil Jones to Michael E. Mann which contains the line "I can't see either of these papers being in the next IPCC report. Kevin and I will keep them out somehow - even if we have to redefine what the peer-review literature is !"[7][9] Anthony Watts, owner of the blog "Watts Up With That?", questions the honesty and scientific integrity of the CRU climate scientists when he writes: "A few of the CRU e-mails suggest that manipulation of climate data in order to reduce the signature of natural climate variations, and to exaggerate the supposed evidence for manmade climate change, is OK with these folks. Apparently, the ends justify the means."[17]

Investigative committees found no evidence of deliberate scientific malpractice or fraud in the case; although, they were critical about the CRU scientists' communication practices. The Independent Climate Change Email Review Committee concluded: "there has been a consistent pattern of failing to display the proper degree of openness, both on the part of CRU scientists and on the part of the UEA"[18]. The committee concluded the modified graph by Phil Jones was misleading because it lacked proper labels, even though this was not intentional by the CRU scientists. [18] Similarly, James Hansen, director of NASA's Goddard Institute for Space Studies in New York, argues: "the data behind any analysis should be made publicly available."[19] He also believes organizations, such as IPCC or the National Academy of Sciences, should not try to block publication of "shoddy science" and instead should "summarize the full range of opinions and explain clearly the basis of the scientific assessment" because "the 'contrarians' or 'deniers' do not have a scientific leg to stand on."[19]

Impact on Public OpinionEdit

Many believed that Climategate was, as UK journalist Fred Pearce puts it, "a public relations disaster."[20] For instance, A. A. Leiserowitz, Director of the Yale University Project on Climate Change, argues: "Climategate had a significant effect on public beliefs in global warming and trust in scientist," but mostly among conservatives. [21] American author and political commentator, Steven F. Hayward, believes: "Climategate did for global warming controversy what the Pentagon Papers did for the Vietnam war 49 years ago: It change the narrative decisively."[22] Patrik Jonsson, a spokesperson of the nonprofit news organization Christian Science Monitor, states: "while public opinion had steadily moved away from belief in man-made global warming before the leaked CRU emails, that trend has only accelerated."[23]

Research suggests Climategate had a temporary effect on public opinion.[24] Climate scientist, Greg Goldsmith, states: “intense media coverage of an event such as 'climategate' was followed by bursts of public interest, but these bursts were short-lived.” Goldsmith suggests there is "no long-term change in the level of climate change scepticism.”[24] Goldsmith specifically tracked searches for "climategate" from November 1 to December 31 and found that the search frequency dropped by 50 percent every six days.[25] In addition, Jon Krosnick, professor of psychology and polling expert at Stanford University, argues that there is not much evidence that the "general public in the United States is picking up on the (University of East Anglia) emails. It's too inside baseball."[26]


Based on a review of sources for climategate, the CRU scientists involved in this email controversy do not portray the definition of professionals. The language used in their email conversations suggest the scientists were attempting to suppress data contradicting their previously published works. By the definition of a professional, a researcher is a person who investigates scientific questions in order to advance human knowledge and understanding of natural phenomena. Based on this criteria, the CRU scientists do not exemplify professional researchers as their emails suggests they were prioritizing their scientific reputations over advancing human knowledge; thus, these scientists represent careerists. They prioritize their careers over their profession. This case can be extended by reviewing the emails and documents in the controversy that were less publicized by the media. This extension will further the case by providing a more complete review of this email controversy.


  1. Climate Research Unit: History of the Climatic Research Unit. (2016).
  2. a b Hickman, L. & Randerson, J. (2009, November 20). Climate sceptics claim leaked emails are evidence of collusion among scientists. The Guardian.
  3. Adam, D. (2010, July 8). Climategate scientists cleared of manipulating data on global warming.
  4. a b c National Oceanic and Atmospheric Administration. (2011, February 24).
  5. a b Norfolk Constabulary. (2012, July 19). Norfolk Constabulary: Police closes UEA investigation.
  6. a b c Costello, J. (2010). The Climategate Emails. Jouhn Costello and the Lavoisier Group Inc., [online]
  7. a b c d Revkin, A. C. (2009, November 20). Hacked E-Mail Is New Fodder for Climate Dispute. The New York Times. Retrieved from
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  12. Cook, J. (n.d.). Climate Science Glossary. Retrieved from
  13. a b c Yekel, C. (2010, June 4). RA-10 Final Investigation Report Involving Dr. Michael E. Mann. The Pennsylvania State University.
  14. a b The United Kingdom Parliament House of Commons. (2010, March 31). The disclosure of climate data from the Climatic Research Unit at the University of East Anglia - Science and Technology Committee.
  15. a b The University of East Anglia. (2010, September 2). UEA Independent Climate Change E-mails Review.
  16. a b National Science Foundation Office of Investigations. (2011, August 23). Closeout Memorandum on Case Number A09120086.
  17. Watts, A. (2009, November 22). Spencer on elitism in the IPCC climate machine. Retrieved May 6, 2018, from
  18. a b Adam, D., & correspondent, environment. (2010, July 7). “Climategate” review clears scientists of dishonesty over data. The Guardian. Retrieved from
  19. a b Begley, S. (2009, November 28). James Hansen Talks About Climate Change | Newsweek Environment | Retrieved May 6, 2018, from
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