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What do the 'Climategate' hacked CRU emails tell us?

What the science says...

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Several investigations have cleared scientists of any wrongdoing in the media-hyped email incident.

Climate Myth...

Climategate CRU emails suggest conspiracy

“[T]he 1079 emails and 72 documents seem indeed evidence of a scandal involving most of the most prominent scientists pushing the man-made warming theory - a scandal that is one of the greatest in modern science. […] emails suggesting conspiracy, collusion in exaggerating warming data, possibly illegal destruction of embarrassing information, organised resistance to disclosure, manipulation of data, private admissions of flaws in their public claims and much more.” (Andrew Bolt, Herald Sun)

At a glance

What do you do if you cannot overturn well-established scientific theories by fair means? In the case of climate science deniers, you cheat. You play foul.

This is exactly what happened in November 2009. Sometime earlier, the email server at the Climatic Research Unit, University of East Anglia, was hacked (an illegal act in itself). A huge number of emails were stolen, sifted through and a selection was made available for download on a Russian server. The timing of the release was unsurprising, for early the following month the COP15 Climate Summit was due to be held in Copenhagen.

Selectively quoting parts of an email message removes all context. One of the most widely-quoted sentences, that will do nicely as an example, was as follows:

"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."

Those fanatically promoting this conspiracy theory encouraged people to take such sentences at face value. The implication that was intended to be the take-home in this case was that climate scientists were covering up declining temperatures. However – and serial misinformers have a long track-record in this kind of thing - it means nothing of the sort. The people in that email were not talking about measured temperatures. Let's take a look at the context to find out what it really meant.

"Mike's Nature trick" referred to a technique described in a 1998 Nature paper, presenting a 600 year-long global temperature reconstruction by Michael Mann and colleagues. Michael is a palaeoclimate specialist who has for many years used tree-ring growth patterns in ancient wood to reconstruct conditions at the time those rings formed. The basic idea is that in cold, dry years, trees grow more slowly so their rings are relatively narrow and densely-spaced. In warm wet years, it's the opposite.

The "trick" is the technique of plotting recent instrumental data (i.e. weather observations) alongside the reconstructed tree-ring data for the time they overlap. It's a good way of checking if the reconstructed tree-ring data are representative and meaningful. They're no good for anything if they are not.

So, what does the “decline” refer to? It's also known as the 'divergence problem', a point on the timeline beyond which the reconstructed tree-ring data stop being representative and meaningful. This is a well-known issue in certain tree-ring datasets from specific places. What happens is that when plotted against instrumental temperature data, the reconstructed tree-ring data fall away – decline - below the instrumental data. This is a recent phenomenon that only showed up after about 1960. Prior to that, it hadn't been a problem.

Climate scientists started discussing the decline in the literature as long ago as 1995 – by which time they had many years of data showing that, where present, it stood out like a sore thumb. It seems to have been caused by an apparent loss in temperature-sensitivity with respect to certain species of trees growing in certain areas. Something had changed, making affected datasets unrepresentative of actual conditions.

All that ado about nothing. Just how much taxpayer's money was wasted on all the public inquiries that followed is anyone's guess. None were necessary. All you need to remember is that when it comes to climate science deniers, the difference between fair means and foul is at best blurred and more usually non-existent.

Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!

Further details

In November 2009, the servers at the University of East Anglia in Britain were illegally hacked and emails were stolen. When a selection of emails between climate scientists were published on the internet, a few suggestive quotes were seized upon by many claiming global warming was all just a conspiracy. A number of independent enquiries have investigated the conduct of the scientists involved in the emails. All have cleared the scientists of any wrong doing:

  1. In February 2010, the Pennsylvania State University released an Inquiry Report that investigated any 'Climategate' emails involving Dr Michael Mann, a Professor of Penn State's Department of Meteorology. They found that "there exists no credible evidence that Dr. Mann had or has ever engaged in, or participated in, directly or indirectly, any actions with an intent to suppress or to falsify data". On "Mike's Nature trick", they concluded "The so-called “trick”1 was nothing more than a statistical method used to bring two or more different kinds of data sets together in a legitimate fashion by a technique that has been reviewed by a broad array of peers in the field."
  2. In March 2010, the UK government's House of Commons Science and Technology Committee published a report finding that the criticisms of the Climatic Research Unit (CRU) were misplaced and that CRU’s "Professor Jones’s actions were in line with common practice in the climate science community".
  3. In April 2010, the University of East Anglia set up an international Scientific Assessment Panel, in consultation with the Royal Society and chaired by Professor Ron Oxburgh. The Report of the International Panel assessed the integrity of the research published by the CRU and found "no evidence of any deliberate scientific malpractice in any of the work of the Climatic Research Unit".
  4. In June 2010, the Pennsylvania State University published their Final Investigation Report, determining "there is no substance to the allegation against Dr. Michael E. Mann".
  5. In July 2010, the University of East Anglia published the Independent Climate Change Email Review report. They examined the emails to assess whether manipulation or suppression of data occurred and concluded that "we find that their rigour and honesty as scientists are not in doubt."
  6. In July 2010, the US Environmental Protection Agency investigated the emails and "found this was simply a candid discussion of scientists working through issues that arise in compiling and presenting large complex data sets."
  7. In September 2010, the UK Government responded to the House of Commons Science and Technology Committee report, chaired by Sir Muir Russell. On the issue of releasing data, they found "In the instance of the CRU, the scientists were not legally allowed to give out the data". On the issue of attempting to corrupt the peer-review process, they found "The evidence that we have seen does not suggest that Professor Jones was trying to subvert the peer review process. Academics should not be criticised for making informal comments on academic papers".
  8. In February 2011, the Department of Commerce Inspector General conducted an independent review of the emails and found "no evidence in the CRU emails that NOAA inappropriately manipulated data".
  9. In August 2011, the National Science Foundation concluded "Finding no research misconduct or other matter raised by the various regulations and laws discussed above, this case is closed".

Just as there are many independent lines of evidence that humans are causing global warming, similarly a number of independent investigations have found no evidence of falsification or conspiracy by climate scientists.

Note: Updated on July 8, 2023 to correctly name CRU as the Climatic Research Unit.
Updated on July 12, 2024 to use archived links where needed and to open links in a new tab

Last updated on 8 July 2023 by John Mason. View Archives

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The House of Commons report on the emails stolen from CRU has vindicated Phil Jones -- he has "no case to answer":

The focus on Professor Jones and CRU has been largely misplaced. On the accusations relating to Professor Jones's refusal to share raw data and computer codes, we consider that his actions were in line with common practice in the climate science community. We have suggested that the community consider becoming more transparent by publishing raw data and detailed methodologies. On accusations relating to Freedom of Information, we consider that much of the responsibility should lie with UEA, not CRU.

In addition, insofar as we have been able to consider accusations of dishonesty--for example, Professor Jones's alleged attempt to "hide the decline"--we consider that there is no case to answer. Within our limited inquiry and the evidence we took, the scientific reputation of Professor Jones and CRU remains intact. We have found no reason in this unfortunate episode to challenge the scientific consensus as expressed by Professor Beddington, that "global warming is happening [and] that it is induced by human activity"

Official statement from Climatic Research Unit (CRU)

In an interview with Andrew Freeman, historian Spencer Weart puts Climategate and the global warming skeptic phenomenon in perspective:

"...we've never before seen a set of people accuse an entire community of scientists of deliberate deception and other professional malfeasance. Even the tobacco companies never tried to slander legitimate cancer researchers."

George Monbiot reveals the most damaging email in The Knights Carbonic. Here is an excerpt, revealing the depth of the climate conspiracy:

"Then began the most hazardous task of all: our attempt to control the instrumental record. Securing the consent of the scientific establishment was a simple matter. But thermometers had by then become widely available, and amateur meteorologists were making their own readings. We needed to show a steady rise as industrialisation proceeded, but some of these unfortunates had other ideas. The global co-option of police and coroners required unprecedented resources, but so far we have been able to cover our tracks.
Our co-option of the physical world has been just as successful. The thinning of the Arctic ice cap was a masterstroke. The ring of secret nuclear power stations around the Arctic Circle, attached to giant immersion heaters, remains undetected, as do the space-based lasers dissolving the world’s glaciers.
Altering the migratory and reproductive patterns of the world’s wildlife has proved more challenging. Though we have now asserted control over the world’s biologists, there is no accounting for the unauthorised observations of farmers, gardeners, bird-watchers and other troublemakers. We have therefore been forced to drive migrating birds, fish and insects into higher latitudes, and to release several million tonnes of plant pheromones every year to accelerate flowering and fruiting. None of this is cheap, and ever more public money, secretly diverted from national accounts by compliant governments, is required to sustain it."

Another amusing parody is Newtongate: the final nail in the coffin of Renaissance and Enlightenment ‘thinking’ which scrutinizes the private correspondance of Isaac Newton to cast doubt on Newtonian physics and integral calculus.

MediaMatters examines many of the claims coming out of "Climategate", exposing how the emails have been distorted and misrepresented.


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Comments 51 to 75 out of 81:

  1. I can't be bothered to "define" smart consumption for you. You've don't it twice for your self I don't suppose anything I have to say will make any impact. And, yes, I can see you're lost; but as you say, you're not the subject of this thread so I'll leave that there.
  2. batvette @49, the review board was not from the same faculty as Michael Mann, and hence independent. As to the "other flaws", we have been through this before @29, 35, and 37 above. There we established that: 1) You just make up "facts" because they suit your argument; and 2) The allegations against Michael Mann where reviewed using the standard procedures as laid down by their by-laws for Penn State, procedures which are in line with those typically required in US and Australian universities. You had nothing of substance to say then, and the mere passage of time adds nothing to your attempts to beat up an issue where none exists.
  3. batvette "It comes down to people don't drive their kids to Disneyland." Why wouldn't they if they had an electric vehicle and there were recharge/replace facilities along the highways instead of servos? Or they could choose high speed rail powered by electricity (from renewable sources). You're confusing conservation with efficiency. Conservation is about using less of something in order not to waste it. Efficiency is about using the best resource for the task. For transport, using fuel that doesn't have to be mined, transported and burned is much more efficient.
  4. batvette wrote : JMurphy, is this statement disinformation or false? "Michael Mann's conduct was examined by an internal, not independent, review board of the entity which employed him and stood to lose credibility if it were revealed he acted improperly." This is what I've been saying, it's all that I'm saying, (on that matter) and if you are going to accuse me of "purveying disinformation" please specify what about it is. It's very simple : The guidelines for such an investigation - acceptable to be used for any other individual except Dr Mann, according to the so-called skeptics, it would appear - are : The Committee shall consist of at least five tenured University faculty members, each of whom should have no conflict of interest and be competent, in the judgment of the Vice President for Research, to evaluate the questions before the Committee. In this case, the individuals involved came from the Departments of Biology, Chemistry and Physics, Computer Science and Electrical Engineering, Anthropology, and Human Development and Family Studies. Again, unbiased enough for any individual except Dr Mann, presumably. Ultimately, if Dr Mann had acted improperly, and it could be proved that he had, the university would have been more than keen to ensure that punishment would have been swift and proportional - if only to preserve the integrity and professionalism of the university itself. The fact that it found no such thing, due to the distinct lack of any form of evidence in the real world, still smarts with the so-called skeptics. Less of the disinformation and more of the facts, please.
  5. We can only wish Wegman would be subjected to such diligent inquiry by his employing institution. As for McIntyre, he's not at risk, no institution employs him, so who will conduct an official investigation? It's good to be a skeptic; all the glory, none of the responsibility...
  6. @JMurphy: The only disinformation is your continued accusation that's what I am doing when I state: "Michael Mann's conduct was examined by an internal, not independent, review board of the entity which employed him and stood to lose credibility if it were revealed he acted improperly." Which I simply asked you to point out what about it was such- you could not, [inflamatory deleted] [inflamatory deleted] ... that because University of Pennsylvania faculty members are from different departments than Dr. Mann, this constitutes an unbiased form of review in a matter which could place the institution's reputation at stake, but buying I'm not. This form of review which is standard at large universities is fine and dandy for matters of scope on a scale of student-teacher interactions, academic controversies like scoring papers, etc. When their work becomes influential enough that it leads to national and international policy affecting all of our lives being forged down the road, it is wholly inadequate and amounts to "good 'ole boy" culture of corrupt justice. You provide a passage which supports just what I am saying, inasmuch as it describes how these faculty members should not have a "conflict of interest", if you can describe how they all do not share the same interests of being faculty members under the employ of the same institution I'm all ears.
    Response: [Dikran Marsupial] Please acquaint yourself with the comments policy; any more of this inflamatory tone from any participant on this thread and I will start deleting posts.
  7. It would seem a large number of people would like PennState to break the law over this. Universities function under three things: National laws, their bylaws/regulations and their charter, given them by the government. Their regulations state how accusations of misconduct (in teaching or research) should be treated. This comes under the terms of their charter and if they do not respect those procedures the government can have an external enquiry, remove their charter and they're out of business. On the other hand, any acts which violate national law is prosecuted in court. Justice is blind. No one can decide, outside of the described terms, that some situation is big enough or annoying enough or news-worthy enough to treat in a special or partial way. That is corruption. What batvette and others are advocating is that people should act corruptly and treat some complaints differently to others because, well, they just feel they should. Pointing at the system and saying "well, that looks like 'good 'ole boy' culture" either has to be substantiated and tackled under national law or has to be seen as a bit of a 'look! rabbit!' trick to distract from their desire for lynch-mob 'justice'.
  8. Very true, les. Having posted a link previously to the guidelines for such a enquiry (To establish a means to handle inquiries and/or investigations into questions of ethics related to research and other scholarly activities), it would appear that such guidelines are fine for everyone except those like Dr Mann, who, presumably, should be subject to the full force of criminal law - as long as it leads to serious consequences for him. If such a legal route were also to acquit him, then the legal route must also be dismissed as biased and part of that all-encompassing conspiracy, Mann will then be judged by the blog 'scientists' and commentariat, and their followers, in the docks of the Denialosphere. In the end, nothing will satisfy some people except the public humiliation of climate scientists, following a show-trial decided by debate and a show of hands...
  9. 58 - JMurphy - yes, I was nodding in the direction of your post. I've been racking my mind to think of any organisation - publicly or privately funded - which tackles complaints in general and misconduct in particular, with anything but an internal panel of professionals from around the organisation; given that the complaint isn't a violation of national law. ...and I mean examples from within the modern western democracies - I'm not, of course, including the USSR, Maoist China etc. I'm sure no one on any part of the mainstream political spectrum would want to encourage political interference anywhere near that level...
  10. les wrote: "I'm sure no one on any part of the mainstream political spectrum would want to encourage political interference anywhere near that level..." Haven't been keeping tabs on Ken Cuccinelli, have ya? :]
  11. 60 CBDunkerson ;)
  12. The link to the US Department of Commerce in point 8 of the list of inquiries clearing the scientists (Intermediate rebuttal) is now broken.
  13. I got a 60 page report with ove 228 points of legiminate criticism (with propoer citation) why the trial and questioning may be fuzzy.

    [DB] If you want to be taken seriously, dispensing denialist literature with a sweeping hand-wave does you no favors.

    A focus on the science is best.

  14. Apparently there has been a fresh batch of emails release from CRU. Fresh round of hacked emails
  15. "Apparently there has been a fresh batch of emails release from CRU." Hmmm. The perpetrator claims to be deeply deeply concerned about transparency and openness... and is therefor anonymous.
  16. What a distraction from the real issues; just what the deniers needed. But there's a bit of good news in the Guardian article: Norfolk police have said the new set of emails is "of interest" to their investigation to find the perpetrator of the initial email release who has not yet been identified. Wasn't there a self-proclaimed major news outlet recently involved in an email hack scandal in the UK? Seems like a trend developing ...
  17. Philippe Chantreau - The Richelieu quote was from me, directed towards josiecki and pointing out how out of context quotes were abused by folks wishing to deny the science. 

  18. Since late 2009 this somewhat heated debate has gone on, "deniers" are falliing off the wagon by droves.  Only the most  "attached to their arguments"  persons can fail to accede to some facts, inconvenient or not, that the reality bearing down will affect us all the same.


    "It's not that warm", saith the lobster, turning pinkish..

  19. All:

    Per his/her request, the most recent post of josiecki has been deleted. DSL's response to it has also been deleted. 

  20. Waiting for a response....


    [JH] You hae requested that all of your comments be deleted. Your request will be honored.

  21. I seriously object to the actions of the moderator in complying with josiecki's requist.

    She does not have the right to request the deletion of anybody's posts other than her own.  Nor does she have the right to remove the context of other people's replies to her by removing her posts.  Therefore the complete removal of all her posts is an unreasonable request that should not have been complied with IMO.

    This situation is very different from that in which a poster immediately after posting discovers an error in their post and requests removal before others have responded.  Rather, we have had several days worth of debate removed because josiecki found it personally embarassing just how little she could defend her opinions (none of which, I believe, she ever offered substantive support of).

    I request that the moderators actions in removing those post be reconsidered by the entire moderation team and that the posts be reinstated.


    [DB] The matter has been brought up for discussion.

  22. I'm torn.  I agree with Tom re the posts replying to Josiecki.  On the other hand, I'd argue that error is the actual reason Josiecki wants all the posts removed.  After all, if she believes in the truth of those posts, she'd defend their publication.  I'm also sad about losing such an excellent, sustained example of empty rhetoric.

  23. DSL, a reasonable compromise would be to restore all the posts, but to snip the contents of josieki's posts as per her request with an explanation that her request is the reason for the snip.  Moderators call, of course.


  24. This is indeed a dilemma. Restoring the responses but not the posts would be unfair and even somewhat misleading. Now that decision has been taken to remove all the posts and associated responses, I think mods should stick with it and leave it at at that. Restoring per request only should be grounds for selectively restoring responses, but that would put undue burden on the mods, and the authors would probably be unsatsified because of a loss of context. No real good option, I think it should be left alone now.

  25. Wow, look what happens when you have a life away from online threads...

    A few days back I was reading a rather disingenuous post by josieki and asked her two questions about her observation that science, from her personal experience, is often corrupt. My questions were directed at her personal experience and inquired if working in the corporate world of science for profit that certain shareholder issues may have had more to do with creating the air of corruption she precived then any other explanation…it was her world I wondered if she had considered that possibility. After her opening salvo aimed at the integrity of science she attempted to anchor her point to "Climategate"

    It was her mention of Climategate that caused me to log in and reply I responded and thought I had accurately characterized the nature of this non-conspiracy conspiracy. She started this with an attempt to kick a dead horse that has long ago been shown to be a rotting corpse of cherry pick snippets and out of context personal correspondence that in no way has been shown to establish evidence of scientific collusion in the service of an agenda that is counter to the findings. Now she gets to have my own post pulled and retreat into the ether and anyone who was engaged by her is to suffer a moderated silence?

    The beauty is that there is still a world outside of thread discussions and moderation...time to go enjoy the day.

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