On “Hackergate”: What the Stolen Emails Say About Climate Science

This post is by staff scientist Lisa Moore and EDF’s chief scientist, Steven Hamburg.

As you know by now, a few weeks ago, hackers stole over a decade’s worth of emails from the University of East Anglia’s Climate Research Unit (CRU). Climate change deniers cherry-picked a few phrases from those emails, took them completely out of context, and claimed that they disprove global warming. Nothing could be further from the truth.

There are already a lot of thorough responses to this manufactured non-scandal, including several RealClimate posts (e.g., here and here); a Nature editorial; statements from leading scientists and professional organizations such as the American Meteorological Society and the American Geophysical Union; an Associated Press analysis; a story in Time magazine; a Washington Post interview of a science historian; and (our favorite) a “Climate Denial Crock of the Week” video from Peter Sinclair, featuring Beavis and Butthead. Because the facts can’t be stated too many times, here’s our own response.

The data showing climate change are solid and overwhelming

The evidence for global warming comes from thousands of thermometer readings over many decades, analyzed independently by different research groups. CRU is one of four agencies that reports global temperature trends. Each of these four—NASA, NOAA, CRU, and the Japan Meteorological Agency (JMA)—works independently of the others to process raw temperature data. Even though they use different methods, all four agencies’ results show marked warming trends over the past several decades:

schelsinger figure

Figure by Dr. Michael Schlesinger, Univ. of Illinois, using results from all four agencies.

You can even do the analysis yourself since the raw data are available online. This sort of independent verification is a hallmark of scientific research. Scientists are always double-checking each other’s work to see if they can replicate the results. When multiple, independent researchers come to similar conclusions, it increases their confidence in their understanding of whatever is being studied. In this case, the data clearly show global warming.

And even beyond all this temperature data, the signs of global warming are everywhere:

  • Satellite data, photographic records, and on-the-ground observations confirm that ice sheets and glaciers are melting.
  • Tide gauges and satellite data show that sea levels are rising.
  • Ground surveys by researchers and citizen scientists, and satellite data, have documented dramatic changes in the geographic ranges and lifecycle timing of Earth’s plants and animals.

As with the temperature record, these datasets have been assembled and analyzed by independent researchers from a variety of specialties. Together, these independent lines of evidence consistently show a rapidly warming world.

What the stolen emails really said

Despite this overwhelming body of evidence, the climate change deniers claim to have proof that global warming is a fraud. Their claim is based on two cherry-picked phrases from the stolen emails, taken wildly out of context. Here they are, with the real story.

In the first email, from 1999, Dr. Phil Jones says “I’ve just completed Mike’s Nature trickof adding in the real temps to each series … to hide the decline.” Denialists are latching desperately to “trick” and “hide the decline” in an attempt to nullify the whole body of evidence for global warming. Here’s what they’ve completely misunderstood:

First, as Nature explains, “’trick’ [is] slang for a clever (and legitimate) technique”. In fact, the technique mentioned in the email was published in Nature by Dr. Michael Mann (thus “Mike’s Nature trick”).

Second, what about the “decline”? This refers to the well-known “divergence problem” between tree ring data and actual temperature records. Prior to about 1960, tree ring density tracked temperature change quite well, so scientists considered tree rings a decent proxy for temperature when or where actual measurements were not available. But for reasons scientists are still trying to figure out, tree rings became less responsive to temperature around 1960. In fact, if you compare actual temperatures to tree rings over that time period, the tree ring record appears to decline, even though we know from thermometers that temperatures continued to increase. So it’s wrong to use the tree rings as part of a temperature reconstruction if you know they’re inaccurate. Dr. Jones was “adding in real [temperature data]” to replace those faulty proxies. Nefarious, eh?

The second email that climate change deniers cling to is by Dr. Kevin Trenberth, in which he said, “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.” Here, Trenberth was lamenting the fact that we don’t have adequate observing systems in place to track the details of how heat is distributed among Earth’s systems over short time periods. In fact, Trenberth has explained this problem at length, for example in this paper [PDF]. Remember that science advances by focusing on what we don’t know. In this case, Trenberth was drawing attention to a gap in our understanding of (and the shortage of available data on) short-term internal climate variation. Don’t mistake a discussion of specific uncertainties for a lack of overall understanding.

There’s also been some discussion of emails that reveal scientists’ frustration about what they felt was harassment by the denier camp. Some of these emails are unseemly or even downright insulting to particular individuals, but ultimately we think these comments are merely a reminder that scientists are human and can say not-so-nice things about other people in private.

The bottom line is that there is absolutely no evidence that these scientists altered data. And even if you completely ignore CRU’s temperature reconstructions, you’re still left with an overwhelming amount of independent evidence that Earth is warming rapidly, and that this trend is due to human activities.

The real scandal is that by intentionally sowing confusion, climate change deniers have delayed action on climate change for a very long time. We owe it to our economy, national security, health, and ecosystems—and to future generations—to ignore these kinds of “nontroversies” and finally pass strong cap-and-trade legislation.

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  1. astroknott
    Posted December 18, 2009 at 6:25 pm | Permalink

    Well at least you guys finally addressed this issue. I find it interesting you call it hackergate rather than climategate. It appears more likely that this was leaked by a whistle blower rather than hacked but I digress. I have looked over these emails myself and I find your characterizations of them interesting. What they actually show is a clear pattern of abusive and deceptive behavior. They clearly demonstrate a desire by these scientists to hide their data. Science is supposed to be transparent and open. If the science is there, if the science is solid, then what is the purpose of not complying with freedom of information act requests? This is all paid for with taxpayer money and this information should have been freely available all along.

    Typically when science makes mistakes they are quickly rectified. The Brontosaurus having the wrong head for example. Honest mistake, rectified and admitted to when discovered. Or the Piltdown man. Actual hoax, but again, rectified and admitted to when discovered. Now if these examples had been handled like these emails have been handled then where would science be?

    Your treatment of this is bad for science. This IS a scandal, and not a non-scandal as you say. Scientists who disagree with the so called consensus are ignored, blacklisted, called names, etc. Does “denier” mean anything to you? If you have the science then PROVE your case and quit name calling. You claim that the evidence is overwhelming yet we see that the evidence is suspect.

    No other branch of science has this level of near vitriol. I can question aspects of plate tectonics and not be called a “denier”. I may have the theory explained to me by an expert but I wont be insulted. Only in this branch of science is this kind of behavior tolerated. Why? I can tell you why. Because this branch of science is being used as a tool to advance a political ideology. The entire environmental movement has been hijacked by leftist ideologues, and is nothing but a tool used to advance that ideology. This isn’t about science. This isn’t about the environment. These are just the tools being used.

    The truth will eventually win out. It’s just a matter of time. The only question I have is how much damage with be done to science and the United States before it happens.

  2. michael stephenson
    Posted December 20, 2009 at 9:56 am | Permalink

    naysayers can shout fraud and sham all they want. The fact is that mankind destoying ecosystems all over the world in order to further industry. Compare the world to what it was 30 years ago and then dare to tell us that we are not going from bad to worse. Rivers are drying up, there is less precipitation in the winter months and glacier ice is melting much faster than it was replaced. That did not start to happen until a certain level of carbon emissions was reached. The air quality the average person breathes has steadily gotten worse over the last couple of decades. What do you think we should do about that? I say taking care of the planet is taking care of humankind.

  3. Scott S.
    Posted December 21, 2009 at 1:34 pm | Permalink

    The fact that ‘scientists’ have fudged data and tried to hide observations that counter their theory is not real science; it is fraud clear and clear.

    Instead of successfully hiding data and keeping their theory intact, they have now put into question the whole idea of anthropologic climate warming, one would think doing exactly opposite of what they were attempting.

    Good move!

    And by calling them ‘stolen e-mails’, EDF displays a prickly attitude that shows their more petulant side.

    The fact is that climate is a product of more than CO2 emmissions; it includes solar radiation, solar storms, sunspot activity, the amount of albedo and more.

    It is sad to see such an calamitous event occuring in science, and no amount of excuse-making can cover it up.

  4. Bruce Clements
    Posted December 21, 2009 at 6:25 pm | Permalink

    More dangerous than Dr. Moore’s rebuttal is her missing the tactics and fundamental honesty of the political left with regard to environmental solutions. But then, I would bet she never voted for Bush. I wonder if she leads a “conservative” lifestyle. It seems that a large part of what environmentalist want is for people to live conservatively.
    Further, Dr. Moore has little credence here except with the fellow travellers. After all, I’m a so-called denier yet I’m not on the payroll of any of the advocates, either side. What about the good doctor? Doing policy work for one side doesn’t make you remotely believable. At least not with anything I’ve read on this blog.
    For years I believed in liberal policies until I stopped excusing all of the biased, narrow mindedness of the left. As the respondent above suggests, the “POLITICS” of the environmental movement is afflicted with the same nonsense and tactics of the race lobby. That’s why I stopped contributing to the EDF, and other such organizations, about ten years ago.
    and by the way, do me a favor and tell your treehugging friend to get his/her Prius out of the left lane. Learn HOW to drive you’ll reduce emissions without wrecking the economy. Oh yes, you would save trees by eliminating all that junk (paper)mail I get from you folks.

  5. Posted December 22, 2009 at 4:45 pm | Permalink


    A small portion of the climate data compiled by CRU (which is in the UK, not the US) is classified because those data originate from national meteorological agencies and in the past were often given to CRU on the condition that access to them be restricted.  There is an international World Meteorological Organization resolution that allows member states to place restrictions on data “for reasons such as national laws or costs of production.”  Ideally, all data would be freely available to all researchers, but in practice that’s not the case.  So it’s not a product of any decision made by CRU that they wouldn’t share all their data, but rather the product of the policies of national meteorological agencies.

    As we explained in the post, the conclusion that recent climate change is mostly due to human activities rests on a large amount of evidence, collected over many decades by large numbers of independent scientists from a wide array of specialties, and analyzed many times and in many ways by independent researchers. It is NOT the work of a handful of scientists from a single discipline or one university. All science is similar – our understanding of other scientific issues is built out of many independent measurements, experiments, and analyses, all critiqued (sometimes heatedly!) in the peer review process and in the scientific literature. Scientists just want to get as close to the truth as they can, wherever it leads. In fact, the CRU emails show this process at work.

    The most constructive thing that scientists disputing the conclusions of CRU (or, for that matter, disputing anything in any scientific discipline) can do is to produce independent analyses and submit them to peer-reviewed journals for publication. While one might be able to make a case that any single journal has a bias, there are many possible journals to submit to. The gray literature is very ineffective at separating sound science from unsound science, whereas the peer review process is a well tested mechanism for separating the good from the bad.

    – Lisa & Steve

  6. astroknott
    Posted December 22, 2009 at 7:14 pm | Permalink

    Yes I know the CRU is in the UK I guess I wasn’t clear about that. There is a freedom of information act in the UK as well. This was funded with taxpayer money as is almost all climate research. Taxpayer money from the US, the UK, AU, etc. etc. It is all public funding and therefore should be openly available to all.

    You say some of this was classified. I will just take your word for it. In the reading of the emails that didn’t appear to me to be a concern of these scientists. Maybe I missed something, but it looked more like they just didn’t want the fact that they had virtually no evidence to support their claims to become public knowledge.

    You talk about peer review. These emails clearly show how the peer review process has been perverted by these people. They were peer reviewing each other! Peer reviews that didn’t agree with them were being kept out of important scientific journals. It is clear that this was done intentionally and maliciously. There are literally thousands of scientist that openly and loudly disagree with the IPCC. They are being ignored by the media and by governments worldwide.

    I really have trouble believing you guys don’t already know this stuff. But in case you really are unaware you should go here:


    I know you will probably call this a “denier” site and therefore unworthy of your attention, but it is just a collection of links to hundreds of news articles. You guys continue to claim “consensus”, volumes of data collected over decades, etc. The fact is that there is NOT a consensus, and many of the data collectors do not agree with the IPCC.

    You “warmers” are simply WRONG! I think most of you know it but don’t care because it serves your anti-capitalist agendas. If you don’t know it then you should do a little more research. Science has been politicized and its a disgrace that it has. In no other area of science is there any meaningful devision between the left and the right. Science is what it is. It doesn’t matter if you are a conservative or liberal. The truth is the truth. What we see here is a concerted effort to manipulate the truth to serve an agenda. It’s all exposed now for all to see. Your attempts to gloss over this scandal are only making it more obvious.

  7. paul
    Posted January 16, 2010 at 5:04 am | Permalink

    Lisa Moore writes:

    “Climate change deniers cherry-picked a few phrases from those emails, took them completely out of context, and claimed that they disprove global warming. Nothing could be further from the truth.Climate change deniers cherry-picked a few phrases from those emails, took them completely out of context, and claimed that they disprove global warming. Nothing could be further from the truth.”

    Here we have a typical example of a scientist acting in a very unscientific manner on this issue. Anyone who is even remotely informed on this issue knows that prior to about 2 years ago this issue was called global warming. It wasn’t the “deniers” that changed the lexicon it was in point of fact the advocates of the theory of man made global warming. Also, I do not know of anyone who is engaged in debating this issue denying climate change, which are exactly the words used by Lisa Moore. What is in fact in contention is whether or not climate change (global warming)is being caused by human beings.

    So if Lisa Moore was a professional and unbiased scientist (which she should be by the very nature of her profession), she would not characterize those that disagree with her in such an unprofessional and denigrating manner.

    As to cherry picking the CRU emails, it is her that is cherry picking them, as if I were to take the time, I could find hundreds of examples of these so called scientists fudging the data, attempting to subvert FOIA requests, and turning the peer review process into a sham.

    Not to mention thus far on this site that is solidly promoting human made global warming, thus far those that are taking the time to comment on this issue are not in your camp.

    This particular issue has been created and fostered by none other than The Club of Rome, Edmund De Rothschild, Maurice Strong and the UN for no other real purpose than to have a global government as quoted recently by the new head of the EU, as well as the Secretary General of the United Nations. The carbon trading derivative scheme to be run by the IMF and the World Bank.

    If you truly were real scientists on this website as well as those that are in the CRU, you would have not problem with the peer review process, as it is the leaked CRU emails more than anything show that these scientists do not promote open and unbiased research.

    A typical example of the irrational hysteria surrounding this issue was a response by Al Gore recently in a Congressional hearing about this matter. When asked if there was a real consensus on this issue, he resorted to talking about those that still do not believe that we landed on the moon! He shows utter contempt for those that do not agree with him and his made up hockey stick.

    For those of you that would like another side to this story, I highly suggest either Lord Monckton’s research into it, or ilovecarbondioxide(dot)com

  8. paul
    Posted January 16, 2010 at 5:17 am | Permalink

    Another example of your blatant bias regarding this issue is that you have made no mention about Climategate that Phil Jones has stepped down from his position at the University of East Anglia’s Climate Research Unit, and that Michael Mann the creator of the discredited “hockey stick” is currently being investigated by the University of Pennsylvania on this issue!

    Keep up the unbiased reporting, you only show your unprofessionalism in all of its ugly glory. Thank you.

  9. Posted January 23, 2010 at 9:36 am | Permalink

    Thank you for carefully defining the word “trick.” I went to Dictionary.com too, and you’ve conveniently omitted the first four definitions of the word “trick.” It’s sad you had to go all the way to number four to try to argue this was not about deception.

    trick (trĭk)
    An act or procedure intended to achieve an end by deceptive or fraudulent means. See Synonyms at wile.

    A mischievous action; a prank.

    A stupid, disgraceful, or childish act or performance.

    You clearly lack intelligence, or think the American people do.

  10. Posted March 17, 2010 at 3:45 am | Permalink

    I read a few of your blog posts. Keep up the good work. Look forward to reading more from you in the future.best luck man.