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A Mistake with Repercussions

Filed under: — group @ 27 April 2006

Today, Science published an important comment pointing out that there were serious errors in a climate research article that it published in October 2004. The article concerned (Von Storch et al. 2004) was no ordinary paper: it has gone through a most unusual career. Not only did it make many newspaper headlines [New Research Questions Uniqueness of Recent Warming, Past Climate Change Questioned etc.] when it first appeared, it also was raised in the US Senate as a reason for the US not to join the global climate protection efforts. It furthermore formed a part of the basis for the highly controversial enquiry by a Congressional committee into the work of scientists, which elicited sharp protests last year by the AAAS, the National Academy, the EGU and other organisations. It now turns out that the main results of the paper were simply wrong.

Von Storch et al. claimed to have tested the climate reconstruction method of Mann et al. (1998) in model simulations, and found it performed very poorly. Now, Eugene Wahl, David Ritson and Caspar Amman show that the main reason for the alleged poor performance is that Von Storch et al. implemented the method incorrectly. What Von Storch et al. did, without mentioning it in their paper, was to remove the trend before calibrating the method against observational data – a step that severely degrades the performance of Climate Field Reconstruction (CFR) methods such as the Mann et al. method (unfortunately this erroneous procedure has already been propagated in a paper by Burger and Cubasch (GRL, 2005) where the authors refer to a personal communication with Von Storch to justify the use of the procedure). Another more recent analysis has shown that CFR methods perform well when used correctly. (See our addendum for a less technical description of what this is all about).

How big a difference does this all make? The calibration error in the temperature minimum around 1820, where one of the largest errors occurs, is shown as 0.6ºC in the standard case of 75% variance in the Von Storch et al analysis. This error reduces to 0.3ºC even in the seriously drift-affected ECHO-G run when the erroneous detrending step is left out. In the more realistic HadCM3 simulation, this error is just above 0.1ºC. The error margins (2 sigma) provided by Mann et al. and pictured in the IPCC report are ±0.17ºC (Fig. 2.21, the curves are reproduced in our addendum). It is therefore clear that the model test of Von Storch et al, had it been implemented correctly, would have shown a small but undramatic underestimation of variance and would have barely ruffled a feather.

Error made, error corrected, and all is well? Unfortunately not. A number of questions remain, which need to be resolved before the climate science community can put this affair to rest.

The first is: why did it take so long to correct this error, and why did the authors of the original paper not correct it themselves? The error is reasonably easy to spot, even for non-specialists (see addendum). And it was in fact spotted very soon after publication. In January 2005, a comment was submitted to Science which correctly pointed out that Von Storch et al. had calibrated with detrended data and had therefore not tested the Mann et al. method. As such comments are routinely passed to the original authors for a response, Von Storch et al. must have become aware of their mistake at this point at the latest. However, the comment was rejected by Science in May 2005.

In a paper dated July 2005, Zorita and Von Storch admit their error in passing, writing: “the trend is subtracted prior to the fit of the MBH regression/inflation model (von Storch et al. 2004). […] It seems, however, that MBH have exploited the trends”. It is thus clear that they knew that their central claim of the Science paper, namely that they had tested the Mann et al. method, was false. But rather than publishing a correction in Science, they wrote the above in a non-ISI journal called “Memorie della Societa Astronomica Italiana” that not many climatologists would read.

An unambiguous correction in Science, where the original paper appeared, would not only have been good scientific practice. It would have been particularly important given the large public and political impact of their paper. It would have been a matter of courtesy towards their colleagues Mike Mann, Raymond Bradley and Malcolm Hughes, who had suffered a major challenge to their scientific reputations as well as having to invest a large amount of time to deal with the Congressional enquiry mentioned above. And it would have been especially pertinent given the unusually vitriolic media statements made previously: in an interview with a leading German news magazine, Von Storch had denounced the work of Mann, Bradley and Hughes as “nonsense” (“Quatsch”). And in a commentary written for the March 2005 German edition of “Technology Review”, Von Storch accused the journal Nature for putting their sales interests above peer review when publishing the Mann et al. 1998 paper. He also called the IPCC “stupid” and “irresponsible” for highlighting the results of Mann et al. in their 2001 report.

There were at least two further issues with the Von Storch et al. paper:

– The model run of Von Storch et al. suffers from a major climate drift due to an inappropriate initialisation procedure. Despite starting in medieval times, the model was initialised from a present-day, rather than pre-industrial, climate state – i.e. from a climate affected by human-caused warming. As a result, the Northern Hemisphere temperature in the model drops by about 1.5 ºC during the initial 100-year adjustment phase and keeps drifting down for the coming centuries. This problem is never mentioned and this part of the experiment is not shown in publications, although climate modellers know that such severe disequilibrium must cause a long-lasting climate drift in the remainder of the run. After Osborn et al. (2006) documented this problem, Von Storch et al. repeated their experiment with improved initialisation. Their new run shows that about half the cooling from medieval times to the 19th Century in their original paper was due to this artificial drift, but again they have not published a correction or demonstrated the impact of this issue (see addendum).

– Von Storch et al. also looked at another model, stating: “Similar results are obtained with a simulation with the third Hadley Centre coupled model (HadCM3), demonstrating that the results obtained here are not dependent on the particular climate characteristics of the ECHO-G simulation.” They have repeatedly made similar claims in the media. This is important, as any model result is considered somewhat preliminary until confirmed with an independent model. However, their statement appears to us to be a serious misrepresentation of the HadCM3 results which were shown only in the online supplement to their paper (see addendum).

In their response to the Wahl et al critique, Von Storch et al acknowledge the original problem but in order to salvage their result, they introduce a large ‘red noise’ component into the proxies. This changes the nature of their test and implies an ‘a priori’ loss of low frequency variance instead of trying to calculate whether a particular methodology produces such a loss.

One could view this story as a positive example for the self-correcting process of science: erroneous results are eventually spotted and corrected, even if it sometimes takes time. If only science were at stake here, we’d need say no more: this would have been a sometimes inappropriately sharp, but otherwise regular technical debate about improving the methodology of proxy reconstructions.

Unfortunately, while the dispute has been used in the public arena to score political points, e.g. to discredit the IPCC process and to question all of the relevant climate science, the significance of this dispute for the bigger picture has been wildly blown out of proportion (see here for a previous discussion). We hope that after this new correction, the discussion can move on to a more productive level. The key issue is how we can improve reconstructions of past large-scale climate variability – of which by now almost a dozen exist. We should not lose sight of the fact that the debate here is about a few tenths of a degree – a much smaller change than is projected for the next century. It is also important to remember one principal point: Conclusions on whether recent warmth is likely to have been unprecedented in the past millennium, or the recent extent of human-caused warming, are based on the accumulation of evidence from many different analyses and are rarely impacted by a technical dispute about any one paper such as this.

137 Responses to “A Mistake with Repercussions”

  1. 1
    TCO says:

    The paranthetical comment by Amman and Wahl (a new method has been developed) seems irrelevant. The paper that is under examination is MBH98. Unless the comment is meant to imply some agreement with the general criticism around that paper. That it had flawed methods. Why cite the new method if the old one is not in error?

    [Response: That a better method is now used, does not mean that past methods were in error. Newtonian mechanics is perfectly servicable in most circumstances even though general relativity is better. Things do indeed ‘move on’… – gavin]

  2. 2
    Dano says:


    If wishes were horses, then dreams would ride.



  3. 3
    jim edwards says:

    Quite Ironic !

    Isn’t this reflective of the same basic argument that M&M [the Climateaudit people] have been making for several years ? – That the claims of scientists should be checked before they are allowed to affect substantive public policy ? [Forget for a moment whether any of their other claims have merit or not.]

    Doesn’t this make sense ? The ecological and economic effects are too great to let anybody stall or turbocharge government response without their work being checked. Of course, it would make imminent sense for government to fund training and work of scientists doing the checking.

  4. 4
    teacher ocean says:

    Scientists are people. And people make mistakes. I am a scientist and I don’t have one colleague who considers him or herself above making mistakes [even among ones who think of themselves as semi-godlike]. The problem with applying too much prestige to one journal [like Science] or one paper [like the Von Storch et al paper] simply undermines the scientific process. It’s science papparazzi at its worst. And our society focuses too much on good vs bad scientist rather than good vs bad science. When mistakes are made, it is the responsibility of other scientists to correct it. Hence the peer review system.

  5. 5
    pat neuman says:

    re 3. You think it’s OK that the knew their central claim of their Science paper was false but rather than publish a correction in Science they made a correction in a journal that not many climatologists read? And, you think that when mistakes are made it is the responsibility of other scientists to correct them? I think there needs to be accountability and justice when some mistakes are made. It’s not OK to say we’re human and humans make mistakes. We already know that, too well.

  6. 6
    teacher ocean says:

    Re #4: Yes, but doesn’t Science get any blame? If the scientists’ mistake is so huge and obvious [which in this case it seems to be], then how come no scientist caught it in peer review? How many reviewers did the journal send their manuscript to for peer review? How selective were they in chosing reviewers? Journals like Science and Nature like to sensationalize science. But when mistakes are exposed, they don’t always allow authors to make corrections after the paper is published. Do we know that the authors did not submit their corrections to science for sure? Maybe they did and Science didn’t want to publish it? All I am saying is I don’t know, and I won’t assume.

    I do however have an issue of Nature from a few years ago advocating the use of foraminifer shells in ocean science as their cover story over a beautiful scanning electron microphotograph of a radiolarian.

    Good science begins and ends with contructive and “quality” peer review.

  7. 7
    Arthur Smith says:

    Yeah, that is VERY strange behavior from Science – do you know any more about the review history of the rejected comment? Was any reason given?

    Disclosure: I work for the Physical Review (American Physical Society) journals, where we are very careful about the integrity of peer review.

  8. 8
    Mark A. York says:

    Teacher Ocean that sounds like some editorial/graphics decsion to me. It happens at most NY houses in books too. The art department just liked the “look” of something that wasn’t the focus of the story. I would consider that peripheral at best.

  9. 9
    teacher ocean says:

    Re Arthur Smith: I don’t know anything about the review history of the original paper or any comments. I am very curious about this.

    Mark A York: Yes but Nature is a VERY prestigious SCIENCE journal. They can’t afford to make mistakes like that. They aren’t offering the public aesthetics, they are supposed to be offering “extremely high quality” science.

  10. 10
    raypierre says:

    What’s at issue is not just a matter of making mistakes. Mistakes are a normal, even essential, part of the progress of science, and many people I respect enormously have made mistakes in doing something new, which, once corrected, led to genuine progress. If scientists were too fearful about making mistakes, it would impede creativity. People need to take risks.

    What has been happening in the Von Storch affair is far more serious than the normal risk of false steps. When you do a calculation which appears to give radically different results from that of a generally respected researcher, and when the result being questioned is considered “important,” you don’t immediately launch a holy war declaring the older result “nonsense” to all and sundry. You don’t let your results be misquoted and over-interpreted by senators without issuing corrections. What you do is look at your results very carefully and make very, very sure that you are the one that’s right and not the other guy. If you’re going to raise the kind of big noise that Von Storch did, you have an obligation to be doubly sure you are right, and to take pains to leave no stone unturned. When others suggest ways you might be wrong, you have an obligation to consider them very carefully. When you do find you are wrong, it is not appropriate behavior to cover it up by burying your admission in an obscure journal hardly anybody ever reads.

    So, this is not part of the normal process of making a mistake. This is about the cover-up, and about irresponsibility in attempting to “take down” another scientist’s results without applying the usual cautions and professional courtesy when there is some question about who is right. In fact, a good title for this post would have been “How not to make a mistake.”

  11. 11
    teacher ocean says:

    Re: Raypierre: OK, the authors have been grossly irresponsible [maybe even calculating], but my question still stands: why didn’t peer review catch it? Didn’t Science send this paper to the researchers agaianst whom the holy war was declared by Von Storch for review?

    Yes, it seems to be more “calculated” than just an innocent mistake. But “peer review” is supposed to be the guard against this kind of thing. I think the journal should take some of the responsibility.

    [Response: One shouldn’t necessarily infer that Von Storch et al knew the result was wrong at the time they submitted it. They should have checked more carefully, but I wouldn’t want to jump to the conclusion that they knew it was wrong at the outset. As for peer review, remember that peer review is a very imperfect process, the more so for journals like Nature and Science where the author has only a very limited space to explain his or her methods. The most crucial step in peer review will always be the “self peer review” that an author subjects his or her own work to. Mistakes do get made by editors about the qualifications of reviewers. I also know about some cases where editors have over-ruled serious objections raised by reviewers. Since the peer review process is confidential, we don’t have any way of knowing precisely what went wrong in this case. If I had been sent the paper to review, I’m not certain I would have spotted the the clues that the result was wrong, just from what the what was in the paper. In retrospect, it’s clear enough, and it was probably always clear to experts in the thick of the subject. But keep in mind that reviewers are besieged with papers they need to look at, and don’t have time to do a lot of deep investigation. The reviewers most likely to take the time to do that (I recall from my own unhappy time as an editor) are the authors whose work is being attacked, and those are precisely the reviews that an Editor is most likely to over-ride. –raypierre]

  12. 12
    Steven T. Corneliussen says:

    In my opinion Arthur Smith (#7) asks a crucial question. So I hope that a RealClimate or other appropriate scientist answers it directly, reporting what is known about Science’s rationale or explanation or lack of them — and that Science’s editor in chief Donald Kennedy then does too. It looks like the e-address for people to send their own queries to Dr. Kennedy is He’s a serious man about questions like this. I hope he answers this one.

  13. 13
    Robert Bucke says:

    All scientists make mistakes (including myself).

    Diligent scientists double-check and make few mistakes. They don’t rush half-baked work off to Science.

    All scientists make mistakes.
    Decent scientists correct them, rather than trying to cover them up. The response of Von Storch et al. is still an attempt to cover up, an elaborate smoke-screen trying to tell us: the mistake didn’t matter.

  14. 14
    TCO says:

    Response to Gavin’s “in the post” response to my #1. In certain regimes (speeds), Newtonian mechanics is equivalent to relativity. In other regimes, it is dramatically inadequate. If the difference affects the answer significantly, then (yes), the Newtonian work is WRONG. If it doesn’t affect the answer significantly, then bringing in the newly discovered GR, is a non sequiter. If it’s in a regime where both are equivalent, then mistakes found in a method relying on Newtonian assumptions will also be mistakes with GR assumptions.

    I almost get the impression that the comments about new methods and such are an attempt to deflect criticism of the earlier work. Think about it this way, Gavin (made up example):
    A. The unit cell of gold was determined in 1900 to be 1.00 Angstroms using a lab scale X-ray diffractometer.
    B. Now, in 2000, comes out a paper using synchrotron radiation updating the earlier result and showin 1.0014 Angstroms to be the unit cell size.
    C. I come back and re-examine the earlier paper and see that they made an incorrect assumption of space group. The unit cell must be 1.50 Angstroms.
    D. Analysis: the updated method is irrelevant to the critique of the earlier work. If it were relevant than it would have (in addition to using a more powerful X-ray) have corrected the earlier paper’s space group and shown that the unit cell was 1.5021.
    E. Capisce? ;-)

    P.s. Please do not censor this post. If you value truth-seeking and debate, you need to allow replies to replies and let the discussion proceed. If you are weary of the subject, I will understand if you don’t continue discussion. But I don’t agree with the policy of “on high reply” and then disallowing a response.

    [Response: Science works in many different ways. Some new results do overturn exisiting assumptions and show that previous work was incorrect. Other results sharpen results (based on better measurements for instance) that were within the uncertainties of the older work – that actually happens much more often. A good example of the first is the mass of the electron. I should probably check, but I recall that modern measurements are significantly outside the error bounds of the first estimates. While a simple example of the second effect could be something like the age of KT boundary. The only point I was making is that newer results do not automatically imply that older results are wrong. – gavin]

  15. 15
    TCO says:

    I’m also (very) interested in the comments about the Burger and Cubash paper implications.

    1. That paper was very critical of work and conclusions from some of the authors of this blog (of MBH98) and presented a very interesting analysis to show this. This blog’s author’s have never directly addressed B&C’s main thesis. The “full factorial of 64 methods” that shows significant differences in the reconstruction by making changes to the method. (I’m not saying you don’t have a response…but you haven’t made it.)

    2. In the arena of this particular topic, I wonder if your implied criticism of B&C for using the detrended data affects their central thesis? Does the graphic showing significant variablity for the 64 method variations collapse if non-detrended data is used? Or is this a side issue?

    [Response: There is a strong case to be made (as above) that the ‘detrending’ variants are ‘a priori’ not valid and so shouldn’t have been included in their analysis. Similarly, the effect of the ‘rescaling’ step is always shown to be positive and so this too can be decided ‘a priori’. I don’t know what the remaining 16 variants would look like. However, you can do better than all of these seemingly arbitrary choices by using better methods (for instance as described in Rutherford et al, 2005) and the results are very similar. That is a much better test of robustness. – gavin]

  16. 16
    Eli Rabett says:

    TCO’s example points to an error without a practical consequence. Those who were using the 0.1 nm (more SI and HTML friendly) value did not have their results distorted. There is a very famous example of a bad measurement that did have consequences that rippled through physics and chemistry. I have it from a professor who was involved as a graduate student and young faculty member.

    According to him (the sanitized version can be found various places on the net including ) when Millikan was working on his oil drop experiment he needed a value for the viscosity of air. He assigned a graduate student to remeasure this more precisely than had been previously done. The student (not my teacher) went to the library, looked up previous work, took an average, and went off to the lab to set up his experiment. The average of his first few measurements came up right on the average of the previous work. The student wrote up his thesis and went off to either fame and glory or obscurity, I don’t know which. Millikan finished the oil drop experiment, using the viscosity value that he had been given and published.

    About 10-15 years later an X-ray method found a slightly (though significantly) different value for the electron charge. There was a furious controversy. The best line that came out of this is that Millikan was rumored to have said: “in 1910 God revealed the charge on the electron to me, to my knowledge there has been no further revelation.”

    Remeasurment of the viscosity of air using several methods, found that it was slightly (but significantly) different from the previously used value. Enough to bring the oil drop and x-ray determinations into agreement, some 25 years after the original publication by Millikan.

  17. 17
    Eachran says:

    This is a good and important post.

    Establishing the truth and accounting for it is one of the most important responsibilities we have as members of humanity. It is, I would say, one of the most significant features of late 20th century global society that, collectively, we have decided to reckon and account for the truth. Everything from the Nuremberg trials to the Truth and Reconciliation Commission in South Africa to the setting up of international institutions to monitor a fairer world bear testament to this. There is no ducking and weaving on this issue and especially not for “scientists”.

    One of the components of this “reckoning”, as I call it, is the recognition of fault : to say “sorry I got this wrong” or, even on occasion, “I lied”. Another equally important component is to forgive and not to forget but to “record” so that future generations (assuming we make it through global warming) “know”.

    Clearly the work of Mr von Storch is an egregious example of “I wasnt too clever with my work” and deserves criticism, and he, along with those implicated – publishers or others – ,should account for themselves to “put the record straight”.

    What more? Well… we are all facing catastrophe with global warming and we need to be honest with each other and to tell the truth if we are going to survive. Equally importantly we need to be vigilant for the next onslaught of the deniers.

    This comment by the “Group” helps the process : please keep going, dont weaken and thanks.

  18. 18
    david Iles says:

    I am an artist and not a scientist. I have been following your discussion and a few others rather avidly in an attempt to understand the parameters of the problem and the way that science works in terms of how reliable the information we in the public are getting on GW. I want to thank you all for offering me this free education.

    Every chance that the public (this includes Legislators) get to dismiss GW they will jump on it. We would love to continue with our northern lives in the way we have come to accept as normal. As long as people can believe that the science is in dispute they will use it for justification. The no-need-to-act side of this argument will always be greeted with relief and open arms.

    What the public needs is a clear statement of the science of GW, and the opinion of the risks we are incurring by ignoring it, by as many leading scientists as are willing to sign onto a statement to that effect.
    (See Comment 64 for my suggestion)
    Dr Hansen has done this. As far as I can tell he stated his informed opinion and not scientifically verifiable fact. This did not make itself clear in his statements to the press and that is truly unfortunate. Clarity on where opinion starts and science ends is an extremely important distinction.

    From what I have been reading the actual peer reviewed science on this most critical of issues is not fully formed. Some scientists are saying we need to wait until we have a better understanding. I fear this will bring a widespread understanding as we watch our planet irreversibly change, from this wonderfully diverse and generous Holocene home we have always known, to a inhospitable, and truncated world, where bird song is replaced with the death rattle, and the western banquet we now expect becomes a hard fight to snatch food from the mouths of rats and cockroaches.

    I have read in other discussions here, about the inadequacy of personal responsibility (i.e. busing, biking, hybrid cars, etc.) and I am sure it is true this alone will not solve the problems we face. I wonder how many of you would agree with this statement: in order to survive this century we will require a world war two-type focus and effort? We will need to mobilize all of our energies, intelligence, and creativity, towards an acceptance and implementation of policies for rabid change. We will have to develop a system of peer review and techniques for modeling new technologies that can move with the urgency made necessary by our inattention and inaction of the past. We will need to (as they did in world war two) require manufacturers and businesses to put up their resources to meet the worlds changing needs. We will have to be willing to export ideas and technology because of the global nature of the problem. And, finally we will absolutely need to cooperate on a global scale to make this work. It will require diplomacy and negotiation that has no precedent in history.

    The start to all of this is up to climate scientist and the quality of the reporting on these issues. That is why I request a clear unambiguous non-jargon filled statement on what we can expect if we continue to move slowly or not move at all on global warming and the variety of causes and problems it presents to us as a species as well as all of our fellow species here on earth.

    I apologies for the length of this comment, and appreciate the indulgence of those who stuck with it.

  19. 19
    Dano says:

    RE 14, 15 and the lurking cheer squad:

    Even though a few folks may wish the worldview they chose for themselves turns out to actually be true, what raypierre says in 10, especially his

    When you do a calculation which appears to give radically different results from that of a generally respected researcher, and when the result being questioned is considered “important,” you don’t immediately launch a holy war declaring the older result “nonsense” to all and sundry.

    is what is left after you stop being distracted by the FUD phrases and hand-waving.

    The reason why certain people with vanity sites can’t get cooperation is because of the italicized. Who in their right mind wants to cooperate with someone who acts this way? It’s like insisting that the scam victim help with the perpetrator’s accounting.

    Now, sadly, this non-cooperation conveniently (and unfortunately), allows the shills to paint the non-cooperators with a brush full of ‘bad actor’ paint. Next we get thunderous denunciations from employees of think tanks in WSJ and other legacy media, usenet boards echoing the latest WSJ op-ed in such volume it becomes spam, and finally certain decision-makers repeating the spam as conventional wisdom.

    It’s time, folks, to stop playing the ‘this deserves a serious discussion’ game and call it for what it is: a game of recycling the same old tired arguments, over and over, regardless of their merit. Period. That’s what it is.



  20. 20
    raypierre says:

    Whatever you can say about Senator Inhofe (and you can say a lot), he certainly did a very effective job at making the Senate aware of Von Storch’s work. What I’m wondering about is: where are the champions in the Senate (of any party, I’m not picky) who can effectively communicate the importance of Von Storch’s error? I don’t want to sound political here: I’m trying to focus on the issues of communicating science. From looking at speeches in the Senate, it often seems to me that Senators arguing on the opposite side to Inhofe do not have a sufficient command of the science to make their side of the case effectively. What do others think about the situation?

  21. 21
    Gavin says:

    I have very little confidence that a) anyone was particularly swayed by Inhofe’s speeches, and b) whether anyone will be swayed by a step by step deconstruction of them. There are plenty of sensible people on the Hill and the hard work of explaining the science mostly goes on behind the scenes and not on the floor. The role of posts like this is to provide background and information, but as others have pointed out – Inhofe and others like him are not being driven by the science, and so arguing at the level on the science is merely to switch the debate away from actual issues.

  22. 22
    Grant says:

    Re: #21

    I have very little confidence that a) anyone was particularly swayed by Inhofe’s speeches, and b) whether anyone will be swayed by a step by step deconstruction of them.

    The real harm caused by Senator Inhofe’s statements to the senate is that they enter the congressional record and become fuel for contrarians, not just in policymaking circles but in the public consciousness. So, entering the refutation into the public record is also important.

    I very much doubt that Inhofe would be persuaded to behave any differently, even if confronted with irrefutable proof. Inhofe will remain in the senate until he is voted out of office by the people of Oklahoma. If senators can show his naivete, misunderstanding, and primitive thinking on the senate floor, it’ll probably do more to persuade Oklahoma voters than any (far more precise and forceful) refutation on the pages of RC.

  23. 23
    Jean S says:

    Sorry if this has been covered here before (I could not find it from the FAQ), but could you explain in layman’s terms how the methodology in von Storch paper is inferior to that Mann et al study? Thanks!

    [Response: This is stated clearly in the Wahl et al abstract (emphasis added):
    von Storch et al. (Reports, 22 October 2004, p. 679) criticized the ability of the “hockey stick” climate field reconstruction method to yield realistic estimates of past variation in Northern Hemisphere temperature. However, their conclusion was based on incorrect implementation of the reconstruction procedure. Calibration was performed using detrended data, thus artificially removing a large fraction of the physical response to radiative forcing.]

  24. 24
    Dano says:

    it often seems to me that Senators arguing on the opposite side to Inhofe do not have a sufficient command of the science to make their side of the case effectively. What do others think about the situation?

    I fully agree, for both sides – I can’t imagine anyone thinking Barton wrote those questions nor anyone thinking he understood more than .06% of the testimony. Nor would I expect more than 2-3% of the House to, either, as the skills necessary to succeed as a politician aren’t shared by scientists (which is part of the problem).

    The key, though, is whether staffers understand the issues, or whether lobbyists have non-understanding staffers’ ears.

    Certainly in committee there should be enough sunlight leaking through that fact-based evidence should sway decision-making.



  25. 25
    Grant says:

    Definitely off topic, my apologies.

    What are the best RC posts about the attribution of global warming to anthropogenic causes?

  26. 26
    Hank Roberts says:

    Grant — start with independenet historical information, copiously referenced. Once you have this basic material read, it’s easier to understand the specific papers being discussed as new science here.

    Discovery of Global Warming (Weart)
    The history of scientific research on climate change from the 19th century to the present, told in a set of hyperlinked essays.

  27. 27
    Mark A. York says:

    I would assert that the articles offered in Science are high quality despite what cover art may not match up to some article contained therein. Unless of course they aren’t, which I doubt.

  28. 28

    Re #18:

    If you are expecting a society-reconstructing manifesto to emerge on realclimate, you are asking the wrong folks. Climate scientists are, as is pointed out elsewhere on this thread, not very good politicians, just as politicians are not very good scientists.

    I think the main policy issue we grappling with here is just how to get to a society which can tell the difference between good information and bad information. That isn’t as grandiose a task as you would have us take on, but it’s still enormously important and very difficult. Realclimate’s only policy mission is to get real science on the table and fake science off the table. Frankly, we seem to be at a loss as to how to do this.

    It often seems that in debates with a strong technical component, the side which is lying, unconstrained by complex, equivocal truth has the advantage. As a general rule, false issues are exagerrated and real issues are minimized. Climate change is unfortunately just one major issue of several where the public and the political sector seems to have increasingly bad information.

    Perhaps if we could reach the point where a network of trust were (re-?) established between genuine scientists and genuine centers of power and influence, we could as a society make better decisions. Failing that, probably any major shake-up would make things worse. In most situations there are more ways to get things wrong than to get them right. A society that can’t use its knowledge effectively is not much better off than one that doesn’t have it in the first place.

    By the way, let me recommend the movie “Thank You for Smoking”, which is not altogether off topic here. The story is a farce, and the moive is not entirely successful, but the methodologies at the core of the story are strikingly realistic, as anyone who has been following the climate policy debate can attest. The scene at the beginning where the tobacco lobbyist on the TV panel attacks the serious, well-intentioned (and dumbfounded) cancer specialist as if he were the most contemptible sleaze imaginable is, at least to a climatologist, well worth the price of admission.

  29. 29
    Grant says:

    Re: #26,

    Thanks for an outstanding resource. However, the actual question is:

    What are the best RC posts about the attribution of global warming to anthropogenic causes?

    [Response: We actually haven’t done many on this though we have asked a couple of people in the D&A community to guest post on the subject. It is a bit of an oversight! However, you can start with for a “poor man’s” attribution study. The follow on paper is also interesting, there is a pop-sci on that available at . I’ll see if I can’t rustle up a post on your specific question though. – gavin]

  30. 30
    Eachran says:

    I was thinking of doing a post on the accessibility of science following on from a number of your recent lead posts but I didnâ??t (looking after visiting family and friends for a few weeks distorts time) : Raypierre raises the issue again in 20 above.

    I believe that the AGW argument is won. From the trivial issue of people, including some UK Government ministers, using Prius as fashion accessories, for example, to the more serious issues where in France, for example, barely a day goes by without French TV running something on global warming or some Department somewhere boasting about its eco credentials. Believe me : many people in France are terrified about the future. Only last night M. Bayrou (a respected centre right politician), in a TV discussion, highlighted global warming as the issue to be addressed.

    But the accessibility issue goes somewhat deeper because it demands people to behave in a different way. To think like a scientist requires a level of rationality that is unfamiliar to the lives of most people. People like to survive in comfort : they donâ??t like to think about the consequences of their actions unless it is proscribed by law. And as we know there are laws and there are laws : I donâ??t see Mr Newton or Mr Einstein embedded in the US constitution for example even though the laws deriving from the work of these two gentlemen have profound effects on the way we live. I shall stop here and perhaps this weekend draft somethingâ?¦.. but maybe notâ?¦we shall see.

    On Grantâ??s request for a primer : Father William recommended IPCC to me and I thought it was very readable and I believe Hank Roberts (was it? Sorry if it was someone else) recommended Stanford University website which I thought was terrific. Just click on the links and educate yourself and good luck it is worth the effort.

  31. 31

    Oops, Sorry About That: Climate Change is Real, After All
    RealClimate today points out that the key piece of peer-reviewed research used politically by climate denialists was, well, botched: Today, Science published an important comment…

  32. 32
    Dano says:

    RE 28:

    It often seems that in debates with a strong technical component, the side which is lying, unconstrained by complex, equivocal truth has the advantage. As a general rule, false issues are exagerrated and real issues are minimized.

    Well, this is the nub. Statements of certitude and unequivocation are looked upon by the gullible as…well…equivocating, aren’t they? The spam that is out there is certain in its citations and denunciation, isn’t it (with certain notable exceptions, of course)?

    Shouldn’t we be able to focus on, first, how to show folk to first turn ON their BS detector, and second, fine tune it to – as Hank is pointing out in another current thread – ask very simple questions when one suspects the salesmen selling you certitude?

    After all, the denialists are all certain that they are correct, whereas the scientists are not certain they are correct. That, basically, is the difference here IMHO.



    [Response: That’s the essence of the problem identified in Steve Schneider’s oft-truncated quote, which if memory serves went something like “Can we be honest, or can we be effective? I hope we can be both.” The skeptics’ certitude makes it tempting to respond by trying to appear more certain than we are, which is a tendency that has to be resisted. That’s why I think it is so important to learn how to communicate the implications of uncertainty — which do not generally imply that inaction is the best course. –raypierre]

  33. 33
    Eli Rabett says:

    As far as a primer, and as out of date as it is (hint, hint) Jan Schloerer’s climate FAQs at Bob Grumbine’s site is still pretty good as are many of the other FAQs there:

  34. 34
    JohnLopresti says:

    It is rewarding to see the inductive process supply a course correction, as peer review serves an essential aim; although some time is lost, the colloquy on the internet has hastened the resolution in this instance. It is a pity a briefly extant sortie of experiments depicted the hockeystick as resting on a tilted surface, as it were, thereby apparently yielding less climb along the vertical axis thru time.

    Within the science community frameworks often create disparities.

    The explanation of the applicability of Newtonian and Einsteinian physics in one comment in this thread approaches a way to appreciate each view for its utility, as science’s views obsolesce.

    Separately, looking only at the Einsteinian calculus, there are proponents of various interpretations of some concepts; and historians have divergent records of the specifics of some experiments. But it is serving as a foundation for further development, imperfectly though it be used.

  35. 35
    david Iles says:


    Thanks for your response Michael and for the movie recommendation.

    Marcel Proust wrote in Swans Way:

    “The facts of life do not penetrate into the
    sphere in which our beliefs are cherished; as it was not they that
    engendered those beliefs, so they are powerless to destroy them;
    they can aim at them continual blows of contradiction and disproof
    without weakening them; and an avalanche of miseries and maladies
    coming, one after another, without interruption into the bosom of a
    family do not make it lose its faith in either the clemency of its
    God or the capacity of its physician.”

    And from Goerge Orwells original (unpublished) introduction to Animal Farm:

    “At any given moment there is an orthodoxy, a body of ideas
    which it is assumed that all right-thinking people will accept
    without question. It is not exactly forbidden to say this, that or
    the other, but it is ‘not done’ to say it, just as in mid-Victorian
    times it was ‘not done’ to mention trousers in the presence of a
    lady. Anyone who challenges the prevailing orthodoxy finds himself
    silenced with surprising effectiveness. A genuinely unfashionable
    opinion is almost never given a fair hearing, either in the popular
    press or in the highbrow periodicals…”

    Your goal of trying to build a society, which can tell the difference between good information and bad information, or as Dano puts it turn ON their BS meters, while a noble one, is hopeless with about half the population.

    53% of Americans believe that God created us in our present form and of those 44% think he did it 10,000 years ago exactly as the bible said, (CBS News Poll. April 6-9 2006) these numbers have remained consistent every since they started asking this question 40 years ago.

    I was not trying to get climate scientists to rebuild society. I was trying to get you to make a simple one page, and intelligible statement, stating what we are likely to face as humans if we continue to move slowly on global climate change. I was asking for a majority vote of informed opinion among climate scientists – a petition- not another long and technically complex paper on CO2 climate forcing, or an argument about tipping points as compared to rapid climate change. It is clear you love to argue the details and I can tell you all would love to nuance the whole issue to death, but most of us just donâ��t understand you. We need a simple basic statement like: If we do not put a major effort into addressing global climate change in the next twenty years we will severely impair most of humanity abilities to survive past 2100?

    I am a painter. I understand nuance. I spend days slightly changing colors to complement each other, it is deeply satisfying, but sort of irrelevant if polar and Greenland ice sheets flow into the sea, farmlands dry up, forests burn, tundra�s release there stored methane and the methane hydrates frozen in the oceans raise to the surface bringing the global temperatures up to where only scorpions and cockroaches can survive. They may in time develop a system of aesthetics but it will probably be fairly different from my own.

    The life threatening and eminent nature of this problem requires all of us to move outside of our area of comfort and at least make a clear statement about where we are heading if we do not make a widespread effort to change. You are the people whose opinions matter, because they are informed. I know you all have opinions about this, what can you agree on?

    I suspect we will wake up to the realities of GW as the oceans seep into our houses and our forests burn. Shouldn’t we at least cry fire in a common language.

    If I simply do not know what I am talking about could someone just take a minute to tell me, please?

  36. 36
    Grant says:

    Re: #35

    > If I simply do not know what I am talking about could someone just take a minute to tell me, please?

    You know what you’re talking about. It was an eloquent appeal for what may, in fact, be a better strategy for reversing public misinformation.

  37. 37
    pat neuman says:

    re 6.


    I do not know how many reviewers get a manuscript for a peer review process.

    National Weather Service (NWS) supervisors send staff manuscripts to NWS scientific services branch for review. My paper on earlier spring snowmelt runoff and increasing dewpoints in the Upper Midwest was sent to NWS Central Region scientific services, but I received no reply. I ended up giving my presentation at the workshop (NWS Climate Prediction Center and Desert Research Institute in Reno, NV, 2003) without hearing back from NWS on whether or not my paper had been approved.

    Thus I was not allowed to hand out my paper on climate and hydrologic change in the Red River basin and the Upper Midwest because the NWS scientific services did not act on my request to have it approved (even though they had more than six weeks to review it). How much time is usually needed by an agency staff to complete review of a paper. If the scientific services branch approves the paper is it then considered peer reviewed?

  38. 38
    teacher ocean says:

    Re Pat Newman: It depends on the journal. Some journals are quick, like AGU [American Geophysical Union] journals will mostly have a decision with reviewers’ comments in 3 months. I am reviewing a paper for an AGU journal which gave me 14 days to return my review. Science and Nature do a quick pre-review where in a week’s time you know if they have deemed your paper appropriate to be sent out for review. I’ve served on panels for the National Science Foundation and know from that experience that each proposal is sent to 7-8 reviewers, but if 3 reviewers respond NSF officers consider themselves lucky. If they get less than 3 reviews for a proposal, then a panel member[s] has to submit a review the proposal.

    I recently had an experience with a scientific journal that illustrates the imperfection [or maybe perfection–don’t want to sound jaded :)] of peer review. I submitted a paper to a journal [let’s leave it nameless] and received 4 reviews. On a scale of 1 [excellent] to 5 [poor] my manuscript received two 1’s, a 2 and a 5. The editor went with the 5. Naturally I will submit elsewhere, but my feeling is not all editors are as fair as Raypierre is [post #11] and sometimes want to support the status quo even if three other reviewers support the authors’ conclusions. But the editor’s decision is final. However, and I am sincere about this, rejections and bad reviews ultimately make a stronger paper, so I am not too upset, just have to work to make my conclusions stronger :)

  39. 39
    Hank Roberts says:

    David Iles:
    You ask for a clear simple statement.

    Raypierre’s latest, just published, is the best I’ve seen.

    You can’t just give this to someone — it’s over 20 pages. I’ve tried, with people who don’t read science — they try and fail to get through it, and I don’t know how it could be clearer. But there’s some mental buffer size that overflows at about 2 pages of real uninterrupted information, nowadays, in many people.

    You can — I do — start from this and find a page, or two, of words worth excerpting that people can sit and slowly read through and get it.

  40. 40
    Grant says:

    Re: #35

    Your post really hit home.

    First of all, in defence of the RC guys, that is not the stated purpose of this site. And maybe, Al Gore is doing more of what you ask for than all the scientists in the world combined.

    But this site is VERY VERY NECESSARY. We live in a democracy, so ultimately the tide will be turned by voter opinion. And a lot of voter opinion is made when discussing news stories over a beer. Ordinary lay citizens want to be able to contradict misinformation, and the more solid background (and refutation of contrarian arguments) they have, the easier and more effectively they can do it. A lot of folks get that here.

    Second, many of us here are scientists, but not climate scientists. We’re unafraid to dive into the latest from Geophysical Research Letters, but without RC it takes so much longer to “get up to speed,” and we know we’re unsure of many of the details (and that the devil is in the details), that RC has made our task immensely easier.

    Twice in the last month I’ve been asked to prepare background information on AGW for very public forums — one for a weblog I subscribe to, the other for a feature story in the local “arts weekly.” Fact is, when people find out you’re a scientist they expect you to be an authority on everything from the DNA sequence of nematode worms to string theory. Well, I’m not. But I’m eager to learn more than “just enough.” And I really don’t want a “dummies guide to global warming.” I want a background summary with a strong technical side, expert opinion, and references to the literature that I can read for myself.

    That’s what I find here. The endless discussion of nuance helps me fill in the gaps, so that I can speak with much greater confidence and persuasiveness. The technical bent enables me to understand the issues far beyond oversimplified naivete. And the literature references enable me to go to the source, read new ideas and new findings, and evaluate them for myself.

    THANK YOU RC. And thank you, David Iles

  41. 41
    teacher ocean says:

    Re #39 [Grant]: I couldn’t agree with you more.

  42. 42
    david Iles says:

    Grant and Ocean,

    I did not for a minute mean to imply that RC is not very valuable in its current form. I also value this site I appreciate being able to listen in on these important discussion even when I don’t understand the scientific details.

    My post was about the issue of communicating about this science – that threatens to have such a profound effect on everyone – in a way that can be discussed and evaluated over a beer among a broad range of peoples interests and abilities. Everyone deserves to hear the message. I made a bit of joke of the way you guys split what appear to be microscopic hairs at times but that does not mean I donâ��t value your purpose in doing so. Specificity is one of the beauties of science.

    I simply want to see a petition taken among informed scientist of what we are currently doing in regards to GW and what the effects of continuing are likely to be. I understand this is a world wide, immensely complex experiment, that humans are doing with very little geological history to rely on for precedent. But like I said you all have opinions is it unfair of me to ask to get a sense of what they are across a spectrum of climate scientists?

    Thanks for the site and for the chance to interact.

  43. 43
    Joseph O'Sullivan says:

    I have not commented in a while. It is good to see RealClimate keeping up with recent developments of science in the public forum, and a hat tip to RC and Raypierre especially for taking the time to respond to the comments!

    Beyond the details of climate science I think it is necessary to tell the non-scientific public how science works. The general points, like what “theory” means when scientists use it to the process of getting published in a scientific journal, are a necessary background. This is clear from some of the threads in the past posts.

    The Peer Review: A Necessary but not Sufficient Condition was a great example of explaining the scientific publication process. Maybe a ongoing series of posts or links of how science works to help to the non-scientist, or something like this ;)

    Some of the things I have seen is calling some of the conclusions or results in papers assumptions or unsubstantiated. Often these are issues addressed in earlier studies and the papers cite to them. To understand what the authors refer to it often means looking at the literature cited to. Each paper usually just covers one issue (the issue covered is usually right in the title) and to understand a field a series of papers need to be reviewed. Here are two useful syntheses of recent climate research:

    Another issue is when scientists make a scientific claim is how certain they are. A very helpful and illuminating statement was given in response by RC to a comment I made in the Worldwide Glacier Retreat post: “we scientists tend not to raise alarms until we are very sure”. Science is based on finding the basis the workings of the physical world and is not like politics or public relations where the goal is persuading people to be on your side of a debate often at the expense of factual correctness. I recall Raypierre in response to a comment writing that the most important thing for a scientist is to be factually correct.

    I think the recent comment that Science published is an example of this process. The far majority of studies confirm the conclusion of Mann et al and the conclusions of the Von Storch paper have not withstood closer examination.

    However I wonder if the editors and peer reviewers of Science were influenced by the public debate about GW. Maybe they thought the Von Storch paper was a close call but not something that should be published, but then they considered the claims of some (e.g. Pat Michaels) that the Journal Science seems to be one-sided in publishing papers that confirm Anthropogenic GW and approved the Von Storch paper so they would not appear one sided? Perhaps this is also the reason the January 2005 comment was rejected?

  44. 44
    Don Baccus says:

    “I simply want to see a petition taken among informed scientist of what we are currently doing in regards to GW and what the effects of continuing are likely to be.”

    The IPCC reports aren’t petition-based but do represent a wide consensus among climate researchers as to how much we can expect temperatures to rise.

    As I understand it (from the POV of a layman with a technical background) there’s far less consensus on the EFFECTS of various levels of warming. It’s far easier to state with some certainty “given a doubling of atmospheric CO2, the average global temperature will rise N degrees” than it is to predict what will happen when temperatures rise that much.

    In fact, the uncertainty as to what will happen as a consequence of global warming is what’s opened the door for the skeptics current favorite trick. “Yeah, OK you’re right after all, it will warm … BUT IT WILL BE GOOD FOR US!!!!”

    Those of us with less of a vested interest in the status quo look at the uncertainty and say, “ummm, well, what research there is doesn’t support the notion that it will be good for us, and why the heck do we want to run an experiment with potentially very nasty outcomes on our own kids and grandkids in the first place?”

    There’s a lot of research going on as to what kind of effects we should be expecting, but there’s an awful lot to learn and that uncertainty is something you can expect skeptics to harp on and harp on and harp on without letup.

  45. 45
    pat neuman says:

    re 38. 37.

    Good explanation in 38 on how peer review works for non-government employed scientists. I still have a couple question though.

    In a government agency, are the peer reviewers employed by the same agency as the person submitting the paper for review?

    I worked for the National Weather Service. If NWS scientific services had reviewed and approved of my paper, could I have said it was peer reviewed?

  46. 46
    teacher ocean says:

    Re #44 [Pat Newmann]: I don’t know anything about the National Weather Service and I am also curious about the answer to your question. But NSF is a government agency also so maybe this will help. Reviewers and panelists for NSF proposals and programs are DEFINITELY not NSF employees, though final decisions about funding are made by NSF officials, naturally. Also, NSF has very strict rules about “conflict of interest.” For example, you can’t review or join panel discussions about a proposal written by your PhD advisor, anyone you’ve collaborated with in the last 5 years [I think that number is right] or any of your former or current students or postdocs. Hope that helps…

  47. 47
    teacher ocean says:

    Wait, I don’t think I answered your question fully Pat Neuman. Peer reviewers for NSF proposals CANNOT be employed by the same institution/agency as the scientists submitting the proposals. That goes under the conflict of interest thing again.

  48. 48
    teacher ocean says:

    I posted something before my “wait” comment but it hasn’t shown up yet :)

  49. 49
    Matt says:

    Real Climate does a good job, pesenting things that are well researched. It would be fun if they spent some time on the more speculative uncertainities of climate, theories we cannot prove but we suspect, or alternative theories where the evidence is slim. This is the fun stuff.

  50. 50
    pat neuman says:


    re 46-48

    In Oct. 2000 I sent a similar draft article on earlier snowmelt runoff in the Red River basin to the Editor-in-Chief of Environmental Protection Magazine. I used my government computer to send it because I had no other email access at that time, but I included a disclaimer that the effort was by me as private citizen. My supervisor found out what I’d done, confiscated my work computer for several months then issued disciplinary action for use of government computer in expressing personal views. Peer review probably wasn’t the issue in 2000, 2003 or 2005 with NWS, climate change was.