Fake Skeptic Criticism of “Decadal Variations in the Global Atmospheric Land Temperatures”

Now that I’ve had the chance to study some of the other papers from the Berkeley team, I’d like to offer my thoughts on Decadal Variations in the Global Atmospheric Land Temperatures (Muller et al. 2011). But first, I’ll comment on another comment about that paper. It has already come under attack from the WUWT crowd, specifically from Doug Keenan. His criticisms are neither valid nor objective, in fact in my opinion his comment amounts to ignorant sniping of the worst kind.

His objections are mainly twofold. First, he objects to the application of a 12-month moving-average filter. He even goes so far as to quote Matt Briggs

Unless the data is measured with error, you never, ever, for no reason, under no threat, SMOOTH the series! And if for some bizarre reason you do smooth it, you absolutely on pain of death do NOT use the smoothed series as input for other analyses!

Keenan concludes “This problem seems to invalidate much of the statistical analysis in your paper.”

I myself have emphasized the problems with smoothing since it introduces artificial autocorrelation into the result. And I have pointed out the folly of analyzing a smoothed series without compensating for the smoothing (see for example here). What seems to escape Keenan (or he chose to ignore) is that Muller et al. do account for the smoothing in their analysis. Instead of applying statistical tests based on an error model for the data (in particular, a white-noise error model which we already know isn’t right), they do their statistical testing by Monte Carlo simulations (in which one generates a large number of artificial signals with the same basic properties in order to define their response to a given analysis). There is simply no merit in this criticism of Keenan’s.

His other main objection is the “statistical model” used. He first states that “most research on global warming relies on a statistical model that should not be used.” He’s referring to the AR(1) (1st-order autoregressive) model. I myself have emphasized the inadequacy of the AR(1) model for temperature time series, and Keenan even supports his assertion by referencing one of my papers (Foster et al. 2007)!

Alas, his reference is not really relevant. We did not show in that paper that an AR(1) model is inadequate for the noise in temperature time series, we showed that it is inadequate for the residuals from a century-scale linear fit. But as I said, I quite agree that an AR(1) model is inadequate for temperature time series — not only is it not correct, it’s not even a close enough approximation to give valid answers.

But Keenan is mistaken when he claims

Although the AR(1)-based model is known to be inadequate, no one knows what statistical model should be used.

On the contrary, I have strong evidence that for temperature time series, an ARMA(1,1) model is adequate. It’s almost certainly not exactly correct (all models are wrong, but some are useful), but it’s a close enough approximation to give valid answers. As a matter of fact I have recently submitted a paper for publication based on this post in which I show that the AR(1) model is inadequate, and argue that the ARMA(1,1) model is the right approach (at least until I see a better one) for trend analysis of temperature time series.

But the salient point is that Muller et al. (2011) does not depend on any statistical model at all. As I said before, they use Monte Carlo simulations for all their statistical testing, and don’t end up making any assumption about the appropriate model for the noise in their data. But Keenan says

BEST did not adopt the AR(1)-based model; nor, however, did it adopt a model that deals with some of the complexity that AR(1) fails to capture. Instead, BEST chose a model that is much more simplistic than even AR(1), a model which allows essentially no structure in the time series.

The implication is that Muller et al. (2011) assumes a white-noise model, which as I’ve already said, is not the case.

Keenan also describes an email exchange on this issue with Doug McNeall at the Hadley Centre, and says of McNeall

He still believes that the world is warming, primarily due to computer simulations of the global climate system.

I very much doubt that’s true. I’m confident that McNeall believes the world is warming, not based on computer simulations but on observed temperature data, the disappearance of glaciers worldwide, the migration of species, changes in the timing of seasonal cycles in the biosphere, disappearance of Arctic sea ice, tremendous mass loss in the Greenland and Antarctic ice sheets, increase in atmospheric humidity, etc. etc. This seems to me to be nothing more than Keenan’s attempt to imply computer simulations are useless (which they aren’t), and that global warming science depends on them (which it doesn’t).

In a genuine example of irony, it seems that even Anthony Watts and his cohorts now say that they believe the world is warming. The ironic part is that the Watts crowd wants us to believe that they never doubted it! All of which is rather effectively belied by quotes from a “paper” on which Watts is first author — not to mention what has consistently oozed from Watts’ blog for years.

Keenan only offers “spin” on Muller et al. (2011). What’s probably most offensive is the hubris which permeates his post, the insultingly condescending tone with which he implies the Berkeley team should go “back to school” and even suggests introductory textbooks on time series analysis.

Hubris and condescension are what we’ve come to expect from posts at WUWT. The only real surprise is just how fervently WUWT is attempting to smear the Berkeley team, their results, and Richard Muller now that the Berkeley team has had the audacity to contradict what Watts & Co. have been asserting for years. The Berekeley group have become WUWT’s current favorite target of ridicule. What a strange reaction from a blogger who originally declared he would “accept whatever result they produce, even if it proves my premise wrong.”


36 responses to “Fake Skeptic Criticism of “Decadal Variations in the Global Atmospheric Land Temperatures”

  1. I don’t read many papers but there can’t be that many which directly accuse others of fraud right in the title

    Then again there probably aren’t that many that use blogs as sources either.

    • You might note this profile of Keenan from RealClimate:

      As an aside, Keenan has made a cottage industry of accusing people of fraud whenever someone writes a paper of which he disapproves. He has attempted to get the FBI to investigate Mike Mann, pursued a vendetta against a Queen’s University Belfast researcher, and has harassed a French graduate student with fraud accusations based on completely legitimate choices in data handling. More recently Keenan, who contacted Wigley after having seen the email mentioned in the Pearce story, came to realise that Wigley was not in agreement with his unjustified allegations of ‘fraud’. In response, Keenan replied (in an email dated Jan 10, 2010) that:

      .. this has encouraged me to check a few of your publications: some are so incompetent that they seem to be criminally negligent.

      Sincerely, Doug


      • 1) One of the panoply of Autism related syndromes.

        2) An eager political neophyte willing to do dirty work for actual wealthy men or political insiders — who don’t even know (or care) if the goop exists — just so the goop can feel a part of The Big Game

        3) Just an ass.

  2. richardjamestelford

    “All models are wrong but some are useful”

    Keenan has taken the first part of Box’s adage to heart. He knows the model must be wrong, and if he just suggests enough problems, someone might believe him. I don’t think he can conceive of the possibility that some climate model might be useful.

    • I don’t know.. if someone came up with a model in which temperatures returned to 20th-century norms within a decade and stayed there forever, regardless of forcings (extra CO2, volcanic eruptions, meteorite impacts, sun going nova, whatever) then he’d struggle to find any problem whatsoever with it, and no doubt would find it very useful.

  3. From Keenan over at Judith’s blog:

    “Their papers would not pass in an introductory course in time series.”

    I find this fascinating.

    He is staking his reputation on the assertion that scientists with acknowledged expertise and years of experience in advanced statistical analysis of complicated problems have produced a paper that would not pass the scrutiny of an introductory course’s standards.

    I suppose he could be right. On the other hand, he could simply be a blind partisan. If I had to bet my mortgage, I’d go with the latter.

    • You are assuming he has a (good) reputation. This is a question which is open to debate.

      • Rattus,

        “You are assuming he has a (good) reputation. This is a question which is open to debate.”

        From Keenan’s “expose” on a certain scientist that was published in E&E (the one that sharper00 links us to):
        “I am grateful to David Henderson, Phil D. Jones, Richard S. Lindzen, and Stephen McIntyre for reading drafts (without necessarily endorsing them) and to the editor, Benny J. Peiser.”

        Me thinks he is not impartial and has an axe to grind. I would not place much stock in Keenan’s vitriolic musings.

  4. Sharper00, nice comment over at WUWT. Looks like that crowd has passed the first stage of denial and are working on the second stage.

  5. Of course the world is warming! Its just coming out of the little ice age, that’s all. But the sort of warming we believe in is different to the sort of warming you believe in. You have to use a different sort of thermometer to measure it. And once you have measured it, you should not talk about it, because then we’d have to agree about it, and we can’t agree about anything except that you are wrong (and corrupt, of course).

  6. “The Berekeley group have become WUWT’s current favorite target of ridicule. What a strange reaction from a blogger who originally declared he would “accept whatever result they produce, even if it proves my premise wrong.”

    I don’t think Muller knows what he stepped into. Sadly, this may cause some heads to explode.

    “Global warming in my evaluation is real and much of it, if not most of it, is caused by humans,”

    –Richard Muller, Sept. 28, 2011


    • Rob Honeycutt

      What’s fascinating is to watch the psychology of all this playing out over at WUWT. I think Watts might have almost (maybe) actually grudgingly accepted the results. Of course he was going to be annoyed by something but I think he might have come around to tossing in the towel on the surface station issue. But what he has created there at WUWT is a highly vocal, highly partisan, bitter, mean following of climate change deniers (deniers with a capital “D”).

      So, what you have are the “enablers” who keep the alcoholic drinking. Watts basically uses these folks to avoid having to accept that there is no basis for his position on climate change. It’s like a bunch of drinking buddies telling the guy, “Nah, all you need is a good stiff drink.”

  7. I thought that the BEST team were a bit arrogant that they were going to judge whether others got it right, others who’s data was in agreement, was BEST ever even likely not to confirm the reality of global warming?

    • Rob Honeycutt

      Who knows? Think of the mark they would have made on the science if they’d found either way, that the temperature was rising faster OR slower than the other data sets! We can claim all day long that it was certain they’d come up with the same results, as we expected (and they did). But we could have been surprised somehow.

      My take is the BEST project goes a long way toward vindicating the work of Hansen and Jones. That’s a very very good thing.

  8. Tamino, I never thought I’d agree with anyone that agrees with Watts about anything but in fact the Muller AMO paper is quite unconvincing, on statistical grounds (not to mention their radical idea that there thermohaline circulation can contribute to global T variability on 2-5 year timescales).

    I don’t think the problems Keenan is raising are important but there is a more basic problem, which is that I can’t even figure out what they did. They test the significance of their correlation of AMO vs. global T series in a plausible (Monte Carlo) way, and conclude it is significant. But they don’t demonstrate whether the AMO correlation with T is greater than the ENSO correlation with T. The autocorrelation in the two time series has been messed with and by a different amount (almost certainly) for AMO vs. ENSO, but I cannot find anywhere in the paper where they make it clear how (or whether) they have accounted for this. Yet it is that point which is supposed to be their discovery. Correct me if I’m wrong, as I’d be very happy to discover that Muller & Co are doing better work than they appear to be, so far.

    [Response: Bear in mind that this post is about Keenan’s criticism, it’s not really about Muller et al. 2011. If find Keenan’s blanket condemnation of their statistics wholly unfounded and unsupported by his arguments, and I believe it’s motivated by other than scientific rationality.

    But that doesn’t mean I agree with Muller et al. 2011. In fact I’m about half-way done with my next post, which is about that very topic.]

    • Timothy (likes zebras)

      You would expect that would be the sort of thing a reviewer would comment on, so it’s a shame that Muller et al decided to go to the Media before peer review was complete.

    • Hi Eric,

      Could you take a look at my post (#353, Unforced variations) on RealClimate and comment on whether or not it’s a reasonable summation of the issues?

      I’m particularly interested in your thoughts on the correlation with the ‘Pinatubo’ temperature fluctuation. Wouldn’t this be an obvious point of discussion when they infer possible physical significance from the observed correlations – the fact that the AMO index strongly correlates with a temperature fluctuation we know it didn’t cause?

  9. Before I get too exercised about all this, (not that likely). Who the hell is Keenan?

    • Gavin's Pussycat

      What the hell is a rhetorical question?

    • This comment at the top of the thread (now–it’s recent as of this writing) tells you a lot about who Keenan is–or at least what he is.

    • Captain Kangaroo’s illegitimate child with Mrs. Green Jeans.

    • Richard, Keenan is a first degree idiot, and kind of an aggressive one. Even though UK oak rings don’t have a very good signal:noise ratio for regional climate recon, he is noted among other things, for the position that they nevertheless are a quite good *global* indicator of cyclical temperature variations. Under the assumption that some dendro scientists at Queen’s University of Belfast were hiding some type of science-altering tree ring data, he pursued lawsuits to force them to release their data, which they did. He comes on to the ITRDB forum every now and then and tries to act like he knows more on the topic than the world’s leading dendrochronologists, and gets fairly shouted down.

    • Richard C, hi,

      See ‘The Guardian disappoints’ article on realclimate.org, linked to from the second post in this thread (author: Rohan), for context. The section you are interested in is titled ‘Part 5: Chinese weather stations’.

    • Horatio Algeranon

      Before I get too exercised about all this, (not that likely). Who the hell is Keenan?

      Well, if you are talking about hell, perhaps getting exorcised would be a better idea.

  10. @”As a matter of fact I have recently submitted a paper for publication based on this post in which I show that the AR(1) model is inadequate, and argue that the ARMA(1,1) model is the right approach (at least until I see a better one) for trend analysis of temperature time series.”

    Unfortunately there is no discussion on this particular topic in the referenced post. Could you elaborate or redirect to the manuscript?

  11. Quick question on a very quoted part of the recent BEST findings – they say:

    “If the long-term AMO changes have been driven by greenhouse gases then the AMO region may serve as a positive feedback that amplifies the effect of greenhouse gas forcing over land. On the other hand, some of the long-term change in the AMO could be driven by natural variability, e.g. fluctuations in thermohaline flow. In that case the human component of global warming may be somewhat overestimated.”

    Wouldn’t also exist a possibility that the human component might be underestimated ???

  12. Keenan as a fake skeptic is not a surprise.

    From his website:

    About the author: I used to do mathematical research and financial trading on Wall Street and in the City of London; since 1995, I have been studying independently.

    “…financial trading on Wall Street and in the City of London;”

    You can’t can’t get any better training in developing the skills of fraud and deceit than the practice of financial trading on Wall Street and in the City of London.

  13. On his website he writes: ” I used to do mathematical research and financial trading on Wall Street and in the City of London; since 1995, I have been studying independently.” http://www.informath.org/

    He has some involvement at wiki to do with charges of fraud against Wei-Chyung Wang:

    He has made such charges in Energy & Environment, to do with UHI:

    Click to access EnE07a.pdf

    He writes about climate, dice, etc.

  14. This is a comment on Watts’ page about Keenan

    “What is it about Global Warming that so attracts the incompetent?”

    I don’t think they mean it the way you’d think they do

  15. If your data shows warming, never smooth it. Never, ever, calculate the trend. Never even look at the data, unless you pick only the tiny bits of it that show cooling.

    If they never denied the warming, I wonder what all the fuss with the “hide the decline” email or the pictures of thermometers in parking lots were all about.

  16. Some comical incoherence over there at WUWT. Within days we’ve gotten:

    -complaints that the BEST papers are not surprising to them, that they accepted the earth was warming all along
    – alongside general attacks on the BEST authors
    – and a return to the same old litany of postings about how NCDC/GISS/CRU can’t be trusted because of their sinister adjustment methods. Which of course they wouldn’t say if BEST papers were so unsurprising to them.

    It doesn’t matter how many independent workers find that they get about the same results as everybody else (GISS/NCDC/CRU), with any reasonable choice of analysis method. There will remain a population of WUWT contributors and commenters who think there is some sort of fraud inherent in the data processing.