The disclosure of climate data from the Climatic Research Unit at the University of East Anglia - Science and Technology Committee Contents

Memorandum submitted by the Public Interest Research Centre (CRU 45)

  The Public Interest Research Centre (PIRC) is a research group, focusing on climate and energy policy. We serve as a resource for policymakers and the public, drawing on scientific and technical materials to provide a clear analysis of their public policy implications.

PIRC welcomes the opportunity to submit evidence. In particular, we will focus on the implications of the CRU leak for the integrity of scientific research.


  Established in 1972, the Public Interest Research Centre is an independent charity (Registered No 266446). Our funding is provided by charitable foundations and individual donations. We do not receive any corporate or government funding.

  1.  Phil Jones' frequently cited proposal to employ "Mike's nature trick" to "hide the decline"[60] does not refer to any attempt to literally conceal information, or decline in the established temperature record.

  2.  This decline refers not to the temperature record, but to one paleo-climate record derived from tree-rings beyond the 1960s, universally recognized as divergent from established, directly observed late-20th century temperature records. Jones was preparing a reliable long-term temperature reconstruction for the World Meteorological Organisation, combining earlier tree-ring data with late 20th century temperature records. As the Pew Centre on Global Climate Change note,

    "It cannot be said that Jones was literally hiding this fact because two years before he wrote this email he was a co-author on the first paper to document this "divergence" issue. That paper, published in Nature in February of 1998, concluded publicly that these post-1960 tree ring data produce inaccurate temperature estimates".[61]

  3.  This background information is referenced in the WMO reconstruction to which Jones was contributing.[62] It is thus clear that none of this information was hidden. The word "trick" occurs frequently across the scientific literature, employed to mean essentially a statistical device, mechanism or "clever thing to do" in handling data.

  4.  Remarks concerning our inability to explain the apparent recent slowdown in rising temperatures refer to the details and complexities of tracking energy flows in the earth system, not whether climate change has stopped.

  5.  In another much-cited email, Dr Kevin Trenberth notes the "travesty" of being unable to explain very recent, short-term variabilities in the overall global temperature trend.[63] This opinion is not simply privately expressed here, but offered alongside a reference to a publicly available, published paper on the issue.[64] The idea that "private doubts" have been concealed from the public is therefore entirely without foundation.

  6.  In this paper Trenberth "unequivocally" backs the scientific consensus on climate change.[65] The issue he raises concerns nuances—in particular, short-term temperature variabilities—in this overall picture. Trenberth's area of study centres around the tracking of energy flows into and out of the climate system. His comment concerns the fact that, in his words "[t]he observing system we have is inadequate" in the difficult and important task of accounting for the complexities in the various mechanisms by which the earth system absorbs and releases heat—within the overall context of man-made climate change.

  7.  Trenberth wrote in a public statement:

    "It is amazing to see this particular quote lambasted so often. It stems from a paper I published this year bemoaning our inability to effectively monitor the energy flows associated with short-term climate variability. It is quite clear from the paper that I was not questioning the link between anthropogenic greenhouse gas emissions and warming, or even suggesting that recent temperatures are unusual in the context of short-term natural variability."[66]

  8.  The structure of the Intergovernmental Panel on Climate Change (IPCC) precludes individual scientists' "keep[ing] out" material or "redefine[ing] peer-review" in preparing reports—and the IPCC process was demonstrably not manipulated in this way.

  9.  In one email, Phil Jones appears to suggest that he and another scientist will endeavour to deliberately "keep out" two papers from the IPCC's Fourth Assessment Report.[67] This is undoubtedly an ill-advised remark, but must be considered in context. The comment was made in private correspondence, in which frivolous or semi-serious comments can be made in haste. Climate scientist Michael Mann comments, "No-one gets to redefine what peer reviewed" means, and the exclamation point underlines the fact that this was hyperbole."[68]

  10.  The exclusion of these papers demonstrably did not happen: these (highly contentious) papers were discussed in the IPCC report, the IPCC process precluding any such attempt at manipulation by individual scientists. As the Pew Centre note:

    "when writing their individual research papers, scientists are free to choose which published papers to cite based on their own judgment, and it is not standard practice to cite all relevant publications, since many are redundant and some lack credibility. In this case, the authors were contemplating the refusal to cite two discredited papers in the IPCC Fourth Assessment Report. In the end, since IPCC reports are more inclusive and comprehensive than individual research papers, both of the suspect papers were cited and discussed (p 466 of the Working Group I report cites Soon and Baliunas, 2003 and McIntyre & McKitrick, 2003; pdf/assessment-report/ar4/wg1/ar4-wg1-chapter6.pdf)."[69]

  11.  In considering this remark, the Committee must take into account these relevant mitigating factors. Its context raises doubts as to the seriousness with which it was made. These doubts are reinforced by the IPCC processes themselves, which are not susceptible to such manipulation, and by the fact that no evidence of wrongdoing was revealed.

  12.  Proposals by senior scientists—discussed as an option—to exclude flawed material from peer-reviewed journals represent a legitimate extension of the peer-review process in extraordinary circumstances.

  13.  As Michael Mann and Gavin Schmidt note, despite its importance as an authenticating and legitimating mechanism for scientific material, peer-review is not infallible, and can be undermined:

    "Put simply, peer review is supposed to weed out poor science. However, it is not foolproof—a deeply flawed paper can end up being published under a number of different potential circumstances: (i) the work is submitted to a journal outside the relevant field (eg a paper on paleoclimate submitted to a social science journal) where the reviewers are likely to be chosen from a pool of individuals lacking the expertise to properly review the paper, (ii) too few or too unqualified a set of reviewers are chosen by the editor, (iii) the reviewers or editor (or both) have agendas, and overlook flaws that invalidate the paper's conclusions, and (iv) the journal may process and publish so many papers that individual manuscripts occasionally do not get the editorial attention they deserve.

    "Thus, while un-peer-reviewed claims should not be given much credence, just because a particular paper has passed through peer review does not absolutely insure that the conclusions are correct or scientifically valid."[70]

  14.  It is clear that the concern discussed in the emails is that two journals—Climate Research and Geophysical Research Letters—are publishing material that is "deeply flawed", "crap"; "crap science", in each case apparently on account of an editorial agenda.[71] The scientists discuss various solutions: writing rebuttals in the journals; sending a letter of protest, signed by a large number of distinguished scientists, to the publishers, expressing their loss of faith in the journal's conduct; bypassing the publication altogether; or gathering and presenting "a clear body of evidence" of the editorial agenda compromising the publication. As the Pew Centre note:

    "To interpret this correspondence in proper context, one must recognize that science is a community-based professional enterprise. It is expected and appropriate that investigators choose in which journals to publish and recommend to their peers in which journals to publish or not publish. The notion of organizing a boycott against any journal that repeatedly departs from accepted scientific standards is both reasonable and ethical."[72]

  15.  Any attempt to exclude material evidently held to be flawed from leading journals must be compared with routine decisions by editors and reviewers to reject publication of material. Rather than an attempt at "suppression", this seems simply to have been an attempt to uphold the integrity of peer-review—an important but not infallible process—in one publication.

  16.   Guardian journalist Fred Pearce raises concerns that the putative independence and anonymity of the peer-review process was compromised in some cases.[73] Mann suggests this is misleading:

    "An editor often asks the scientists being criticised to review a new submission critical of their work. This is in fact expected behaviour since it often allows any misunderstandings or misinterpretations to be resolved ahead of time. It does not imply that the criticised authors have veto power over criticism. The role of the editor is explicitly there to adjudicate these issues and obviously will take into account potential conflicts before making decisions based on *all* of the reviews. The problems most often arise—such as in Soon and Baliunas (2003) or McIntryre and McKitirck (2003;2005) when the criticised authors are not involved at all."[74]

  17.  Unjustifiable attempts appear to have been made to withhold or prevent the release of information, in the context of: (a) a campaign of harassment, misrepresentation and vilification by a major industry-backed lobby; (b) CRU's contractual obligations to keep some data out of the public domain.

  18.  Some emails suggest attempts to keep scientific data out of the public domain, and possibly to delete emails either in anticipation of or response to FOI requests. While such behaviour is unjustifiable, the emails concerned contain evidence of the overarching context of these remarks: the concerted campaign of harassment, misrepresentation and vilification to which the scientists were exposed. As Phil Jones says in one of the emails concerned, "As an aside and just between us, it seems that Brian Hoskins has withdrawn himself from the WG1 [Working Group 1 of the IPCC] Lead nominations. It seems he doesn't want to have to deal with this hassle."[75] NCAR's Caspar Amman wrote in one email: "Oh MAN! will this crap ever end??"[76] Gavin Schmidt writes in one email of the way FOI requests were used to harass scientists:

    "The contrarians have found that there is actually no limit to what you can ask people for (raw data, intermediate steps, additional calculations, residuals, sensitivity calculations, all the code, a workable version of the code on any platform etc), and like Somali pirates they have found that once someone has paid up, they can always shake them down again."[77]

  19.  One FOI submission to the UEA by Climate Audit contained the following paragraph:

    "I hereby make a EIR/FOI request in respect to any confidentiality agreements) restricting transmission of CRUTEM data to non-academics involing the following countries: [insert five or so countries that are different from ones already requested 1]" (emphasis added).

  20.  The request, clearly designed to generate repeated FOI submissions, was treated as vexatious and turned down.

  21.   Nature blogger Olive Heffernan notes:

    "Between 24 July and 29 July of this year, CRU received 58 freedom of information act requests from McIntyre and people affiliated with Climate Audit. In the past month, the UK Met Office, which receives a cleaned-up version of the raw data from CRU, has received ten requests of its own."[78]

  22.  John Houghton, former co-chair of the IPCC told the BBC that information was routinely leaked and manipulated in the public domain by a critical fossil fuel industry lobby to undermine the IPCC:

    "Professor Houghton said that in future it would be wise to offer the IPCC protection from harassment in its work. `IPCC meetings were open to all—including (representatives) from organisations such as [fossil fuel industry lobbying coalition] the Global Climate Coalition whose clear agenda was to weaken our work and our conclusions.

    A particular way they continually did this was to publish selected provisional material from the IPCC process, for example draft chapters or contributions not meant for publication, and used this to discredit the IPCC and the process.

    For people being targeted, it is very difficult to be completely open when provisional material emerging during the process is being used as stick to beat the scientists with'."[79]

  23.  This does not excuse failures to adhere to the openness that robust scientific practice demands, or apparent attempts to circumvent FOI requests, but helps explain why—absent malicious or conspiratorial motives—information was withheld.

  24.  As the Pew Centre note, the CRU had contractual obligations to keep some data private—problematic in terms of transparency, but fundamentally an institutional problem:

    "The CRU is barred by non-publication agreements with some countries' meteorological services from releasing to the public a small amount (less than 5%) of the weather station data the CRU uses to estimate landp-surface temperature trends. The university has confirmed that the CRU is legally barred from releasing these data. A few commentators have used this situation as a basis for accusing the CRU of suppressing data."[80]

  25.  Gavin Schmidt notes:

    "From the date of the first FOI request to CRU (in 2007), it has been made abundantly clear that the main impediment to releasing the whole CRU archive is the small % of it that was given to CRU on the understanding it wouldn't be passed on to third parties. Those restrictions are in place because of the originating organisations (the various National Met Services) around the world and are not CRU's to break. As of 13 November, the response to the umpteenth FOI request for the same data met with exactly the same response. This is an unfortunate situation, and pressure should be brought to bear on the National Met Services to release CRU from that obligation. It is not however the fault of CRU."[81]

  26.  In investigating CRU's responses to FOI requests, the Committee must determine whether such requests represented a pernicious form of harassment through unreasonable, time-consuming requests for extraordinary quantities of data; and whether information was withheld due to contractual obligations.

  27.  No relevant evidence or data has had to undergo a correction or been found to be wrong as a result of the affair.

  28.  As Myles Allen, head of the Climate Dynamics group at Oxford, has commented, the CRU leak leaves us "without any evidence that any number, anywhere, is actually wrong."[82]

    "If it could be proved that figures had been deliberately altered to give a specific result then it would be very serious, but so far no evidence has emerged from these Climatic Research Unit (CRU) emails of any error in the HadCRUT instrumental temperature record at the centre of the row, never mind proof of deliberate intent to mislead ..."

  29.  Fred Pearce's investigation for the Guardian has substantiated this: none of the emails indicates extant erroneous information in the scientific literature requires correction.

  30.  The data sets and scientific literature the emails discuss represent a small portion of the scientific evidence supporting anthropogenic climate change. The flaws and compromises widely alleged are insufficient to seriously undermine this evidence.

  31.  As Nature note:

    "Nothing in the e-mails undermines the scientific case that global warming is real—or that human activities are almost certainly the cause. That case is supported by multiple, robust lines of evidence, including several that are completely independent of the climate reconstructions debated in the e-mails."[83]

  32.  The Pew Centre explain:

    "The two data sets highlighted in accusations of misconduct are very limited and consist of:

    — High-latitude tree ring data that inaccurately suggest that local temperatures declined after 1960; thermometer readings from the same locations demonstrate that the tree rings accurately reflected local temperatures prior to, but not after 1960.

    — A small fraction of the weather station data used by the CRU to estimate global surface temperature change ...

    "The key point is that those data that comprise the most important evidence for human-induced climate change are not in play in the emails, including those documenting:

    — snow and ice cover;

    — sea level rise;

    — ocean heat content;

    — surface temperature records maintained in the U.S. (NASA, NOAA);

    — upper and lower atmospheric temperatures monitored by satellites;

    — atmospheric water vapor;

    — greenhouse gases;

    — solar activity; and

    — modeling experiments.

    "As a result, the evidence for rapid warming of the Earth in recent decades remains unequivocal, including:

    — Worldwide loss of snow and ice.

    — Rising sea levels.

    — Records of rising global surface temperatures maintained in the U.S. by NASA and NOAA.

    "Further, the evidence for human dominance of recent warming remains very strong, including:

    — Concomitant warming of the troposphere and cooling of the stratosphere (a greenhouse effect signature).

    — Without the strong warming effect of human-induced rise in atmospheric greenhouse gas concentrations, the observed changes in solar activity over the past several decades would have led to a slight cooling of the Earth's surface.

    — Climate models only reproduce the warming of the past 50 years when they include the observed rise in atmospheric greenhouse gas concentrations."[84]

  33.  In conclusion, whilst this affair certainly merits further investigation, the media's allegations of wrongdoing have been decontextualised and seriously exaggerated.

February 2010;

Email from Tom Wigley to colleagues, 24 April 2003. Available at:

60   Email from Phil Jones to colleagues, 16 November 1999. Available at: Back

61   Analysis of the Emails from the University of East Anglia's Climatic Research Unit, Pew Centre on Global Climate Change report, December 2009. Available at: Back

62   "CRU update 2", 24 November 2009. Available at Back

63   Email from Kevin Trenberth to colleagues, 12 October 2009. Available at: Back

64   Kevin Trenberth, "An imperative for climate change planning: tracking Earth's global energy", Current Opinion in Environmental Sustainability, Vol 1, pp 19-27; doi:10.1016/j.cosust.2009.06.001. Available at: Back

65   Peter Sinclair, "Climate Crock Sacks Hack Attack Part 1". Available at: Back

66   Kevin Trenberth, "Statement: Kevin Trenberth on Hacking of Climate Files". Available at: Back

67   Email from Phil Jones to colleagues, July 8 2004. Available at: Back

68   Correspondence with Michael Mann, February 2010. Back

69   Pew Centre, op citBack

70   "Peer review: a necessary but not sufficient condition", Realclimate, 20 January 2005. Available at: Back

71   Email from Michael Mann to colleagues. Available at: Back

72   Pew Centre, op citBack

73   Fred Pearce, "Emails reveal strenuous efforts by climate scientists to `censor' their critics", Guardian, 9 February 2010. Available at: Back

74   Correspondence with Michael Mann, February 2010. Back

75   Email from Phil Jones to colleagues, 20 August 2008. Available at: Back

76   Email from Caspar Amman to colleagues. Available at: Back

77   Email from Gavin Schmidt to colleagues. Available at: Back

78   "McIntyre versus Jones: climate data row escalates", Climate Feedback, 12 August 2009. Available at: Back

79   "Harrabin's Notes: Debating the IPCC", BBC Online. Available at: Back

80   Pew Centre, op citBack

81   Gavin Schmidt, "The CRU Hack: Context", Realclimate, 23 November 2009. Available online at: Back

82   Myles Allen, "Science forgotten in climate emails fuss", Guardian, 11 December 2009. Available online at: Back

83   "Climatologists Under Pressure", op citBack

84   Pew Centre, op cit. Back

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