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The Montford Delusion

Filed under: — group @ 22 July 2010

Guest commentary by Tamino

Update: Another review of the book has been published by Alistair McIntosh in the Scottish Review of Books (scroll down about 25% through the page to find McIintosh’s review)

Update #2 (8/19/10): The Guardian has now weighed in as well.

If you don’t know much about climate science, or about the details of the controversy over the “hockey stick,” then A. W. Montford’s book The Hockey Stick Illusion: Climategate and the Corruption of Science might persuade you that not only the hockey stick, but all of modern climate science, is a fraud perpetrated by a massive conspiracy of climate scientists and politicians, in order to guarantee an unending supply of research funding and political power. That idea gets planted early, in the 6th paragraph of chapter 1.

The chief focus is the original hockey stick, a reconstruction of past temperature for the northern hemisphere covering the last 600 years by Mike Mann, Ray Bradley, and Malcolm Hughes (1998, Nature, 392, 779, doi:10.1038/33859, available here), hereafter called “MBH98” (the reconstruction was later extended back to a thousand years by Mann et al, 1999, or “MBH99” ). The reconstruction was based on proxy data, most of which are not direct temperature measurements but may be indicative of temperature. To piece together past temperature, MBH98 estimated the relationships between the proxies and observed temperatures in the 20th century, checked the validity of the relationships using observed temperatures in the latter half of the 19th century, then used the relationships to estimate temperatures as far back as 1400. The reconstruction all the way back to the year 1400 used 22 proxy data series, although some of the 22 were combinations of larger numbers of proxy series by a method known as “principal components analysis” (hereafter called “PCA”–see here). For later centuries, even more proxy series were used. The result was that temperatures had risen rapidly in the 20th century compared to the preceding 5 centuries. The sharp “blade” of 20th-century rise compared to the flat “handle” of the 15-19th centuries was reminiscent of a “hockey stick” — giving rise to the name describing temperature history.

But if you do know something about climate science and the politically motivated controversy around it, you might be able to see that reality is the opposite of the way Montford paints it. In fact Montford goes so far over the top that if you’re a knowledgeable and thoughtful reader, it eventually dawns on you that the real goal of those whose story Montford tells is not to understand past climate, it’s to destroy the hockey stick by any means necessary.

Montford’s hero is Steve McIntyre, portrayed as a tireless, selfless, unimpeachable seeker of truth whose only character flaw is that he’s just too polite. McIntyre, so the story goes, is looking for answers from only the purest motives but uncovers a web of deceit designed to affirm foregone conclusions whether they’re so or not — that humankind is creating dangerous climate change, the likes of which hasn’t been seen for at least a thousand or two years. McIntyre and his collaborator Ross McKitrick made it their mission to get rid of anything resembling a hockey stick in the MBH98 (and any other) reconstruction of past temperature.

Principal Components

For instance: one of the proxy series used as far back as the year 1400 was NOAMERPC1, the 1st “principal component” (PC1) used to represent patterns in a series of 70 tree-ring data sets from North America; this proxy series strongly resembles a hockey stick. McIntyre & McKitrick (hereafter called “MM”) claimed that the PCA used by MBH98 wasn’t valid because they had used a different “centering” convention than is customary. It’s customary to subtract the average value from each data series as the first step of computing PCA, but MBH98 had subtracted the average value during the 20th century. When MM applied PCA to the North American tree-ring series but centered the data in the usual way, then retained 2 PC series just as MBH98 had, lo and behold — the hockey-stick-shaped PC wasn’t among them! One hockey stick gone.

Or so they claimed. In fact the hockey-stick shaped PC was still there, but it was no longer the strongest PC (PC1), it was now only 4th-strongest (PC4). This raises the question, how many PCs should be included from such an analysis? MBH98 had originally included two PC series from this analysis because that’s the number indicated by a standard “selection rule” for PC analysis (read about it here).

MM used the standard centering convention, but applied no selection rule — they just imitated MBH98 by including 2 PC series, and since the hockey stick wasn’t one of those 2, that was good enough for them. But applying the standard selection rules to the PCA analysis of MM indicates that you should include five PC series, and the hockey-stick shaped PC is among them (at #4). Whether you use the MBH98 non-standard centering, or standard centering, the hockey-stick shaped PC must still be included in the analysis.

It was also pointed out (by Peter Huybers) that MM hadn’t applied “standard” PCA either. They used a standard centering but hadn’t normalized the data series. The 2 PC series that were #1 and #2 in the analysis of MBH98 became #2 and #1 with normalized PCA, and both should unquestionably be included by standard selection rules. Again, whether you use MBH non-standard centering, MM standard centering without normalization, or fully “standard” centering and normalization, the hockey-stick shaped PC must still be included in the analysis.

In reply, MM complained that the MBH98 PC1 (the hockey-stick shaped one) wasn’t PC1 in the completely standard analysis, that normalization wasn’t required for the analysis, and that “Preisendorfer’s rule N” (the selection rule used by MBH98) wasn’t the “industry standard” MBH claimed it to be. Montford even goes so far as to rattle off a list of potential selection rules referred to in the scientific literature, to give the impression that the MBH98 choice isn’t “automatic,” but the salient point which emerges from such a list is that MM never used any selection rules — at least, none that are published in the literature.

The truth is that whichever version of PCA you use, the hockey-stick shaped PC is one of the statistically significant patterns. There’s a reason for that: the hockey-stick shaped pattern is in the data, and it’s not just noise it’s signal. Montford’s book makes it obvious that MM actually do have a selection rule of their own devising: if it looks like a hockey stick, get rid of it.

The PCA dispute is a prime example of a recurring McIntyre/Montford theme: that the hockey stick depends critically on some element or factor, and when that’s taken away the whole structure collapses. The implication that the hockey stick depends on the centering convention used in the MBH98 PCA analysis makes a very persuasive “Aha — gotcha!” argument. Too bad it’s just not true.

Different, yes. Completely, no.

As another example, Montford makes the claim that if you eliminate just two of the proxies used for the MBH98 reconstruction since 1400, the Stahle and NOAMER PC1 series, “you got a completely different result — the Medieval Warm Period magically reappeared and suddenly the modern warming didn’t look quite so frightening.” That argument is sure to sell to those who haven’t done so. But I have. I computed my own reconstructions by multiple regression, first using all 22 proxy series in the original MBH98 analysis, then excluding the Stahle and NOAMER PC1 series. Here’s the result with all 22 proxies (the thick line is a 10-year moving average):

Here it is with just 20 proxies:

Finally, here are the 10-year moving average for both cases, and for the instrumental record:

Certainly the result is different — how could it not be, using different data? — but calling it “completely different” is just plain wrong. Yes, the pre-20th century is warmer with the 15th century a wee bit warmer still — but again, how could it not be when eliminating two hand-picked proxy series for the sole purpose of denying the unprecedented nature of modern warming? Yet even allowing this cherry-picking of proxies is still not enough to accomplish McIntyre’s purpose; preceding centuries still don’t come close to the late-20th century warming. In spite of Montford’s claims, it’s still a hockey stick.

Beyond Reason

Another of McIntyre’s targets was the Gaspe series, referred to in the MBH98 data as “treeline-11.” It just might be the most hockey-stick shaped proxy of all. This particular series doesn’t extend all the way back to the year 1400, it doesn’t start until 1404, so MBH98 had extended the series back four years by persistence — taking the earliest value and repeating it for the preceding four years. This is not at all an unusual practice, and — let’s face facts folks — extending 4 years out of a nearly 600-year record on one out of 22 proxies isn’t going to change things much. But McIntyre objected that the entire Gaspe series had to be eliminated because it didn’t extend all the way back to 1400. This argument is downright ludicrous — what it really tells us is that McIntyre & McKitrick are less interested in reconstructing past temperature than in killing anything that looks like a hockey stick.

McIntyre also objected that other series had been filled in by persistence, not on the early end but on the late end, to bring them up to the year 1980 (the last year of the MBH98 reconstruction). Again, this is not a reasonable argument. Mann responded by simply computing the reconstruction you get if you start at 1404 and end at 1972 so you don’t have to do any infilling at all. The result: a hockey stick.

Again, we have another example of Montford implying that some single element is both faulty and crucial. Without nonstandard PCA the hockey stick falls apart! Without the Stahle and NOAMER PC1 data series the hockey stick falls apart! Without the Gaspe series the hockey stick falls apart! Without bristlecone pine tree rings the hockey stick falls apart! It’s all very persuasive, especially to the conspiracy-minded, but the truth is that the hockey stick depends on none of these elements. You get a hockey stick with standard PCA, in fact you get a hockey stick using no PCA at all. Remove the NOAMER PC1 and Stahle series, you’re left with a hockey stick. Remove the Gaspe series, it’s still a hockey stick.

As a great deal of other research has shown, you can even reconstruct past temperature without bristlecone pine tree rings, or without any tree ring data at all, resulting in: a hockey stick. It also shows, consistently, that nobody is trying to “get rid of the medieval warm period” or “flatten out the little ice age” since those are features of all reconstructions of the last 1000 to 2000 years. What paleoclimate researchers are trying to do is make objective estimates of how warm and how cold those past centuries were. The consistent answer is, not as warm as the last century and not nearly as warm as right now.

The hockey stick is so thoroughly imprinted on the actual data that what’s truly impressive is how many things you have to get rid of to eliminate it. There’s a scientific term for results which are so strong and so resistant to changes in data and methods: robust.

Cynical Indeed

Montford doesn’t just criticize hockey-stick shaped proxies, he bends over backwards to level every criticism conceivable. For instance, one of the proxy series was estimated summer temperature in central England taken from an earlier study by Bradley and Jones (1993, the Holocene, 3, 367-376). It’s true that a better choice for central England would have been the central England temperature time series (CETR), which is an instrumental record covering the full year rather than just summertime. The CETR also shows a stronger hockey-stick shape than the central England series used by MBH98, in part because it includes earlier data (from the late 17th century) than the Bradley and Jones dataset. Yet Montford sees fit to criticize their choice, saying “Cynical observers might, however, have noticed that the late seventeenth century numbers for CETR were distinctly cold, so the effect of this truncation may well have been to flatten out the little ice age.”

In effect, even when MBH98 used data which weakens the difference between modern warmth and preceding centuries, they’re criticized for it. Cynical indeed.


The willingness of Montford and McIntyre to level any criticism which might discredit the hockey stick just might reach is zenith in a criticism which Montford repeats, but is so nonsensical that one can hardly resist the proverbial “face-palm.” Montford more than once complains that hockey-stick shaped proxies dominate climate reconstructions — unfairly, he implies — because they correlate well to temperature.



Criticism of MBH98 isn’t restricted to claims of incorrect data and analysis, Montford and McIntyre also see deliberate deception everywhere they look. This is almost comically illustrated by Montford’s comments about an email from Malcolm Hughes to Mike Mann (emphasis added by Montford):

Mike — the only one of the new S.American chronologies I just sent you that already appears in the ITRDB sets you already have is [ARGE030]. You should remove this from the two ITRDB data sets, as the new version should be different (and better for our purposes).

Here’s what Montford has to say:

It was possible that there was an innocent explanation for the use of the expression “better for our purposes”, but McIntyre can hardly be blamed for wondering exactly what “purposes” the Hockey Stick authors were pursuing. A cynic might be concerned that the phrase actually had something to do with “getting rid of the Medieval Warm Period”. And if Hughes meant “more reliable”, why hadn’t he just said so?

This is nothing more than quote-mining, in order to interpret an entirely innocent turn of phrase in the most nefarious way possible. It says a great deal more about the motives and honesty of Montford and McIntyre, than about Mann, Bradley, and Hughes. The idea that MM’s so-called “correction” of MBH98 “restored the MWP” constitutes a particularly popular meme in contrarian circles, despite the fact that it is quite self-evidently nonsense: MBH98 only went back to AD 1400, while the MWP, by nearly all definitions found in the professional literature, ended at least a century earlier! Such internal contradictions in logic appear to be no impediment, however, to Montford and his ilk.

Conspiracies Everywhere

Montford also goes to great lengths to accuse a host of researchers, bloggers, and others of attempting to suppress the truth and issue personal attacks on McIntyre. The “enemies list” includes RealClimate itself, claimed to be a politically motivated mouthpiece for “Environmental Media Services,” described as a “pivotal organization in the green movement” run by David Fenton, called “one of the most influential PR people of the 20th century.” Also implicated are William Connolley for criticizing McIntyre on sci.environment and James Annan for criticizing McIntyre and McKitrick. In a telling episode of conspiracy theorizing, we are told that their “ideas had been picked up and propagated across the left-wing blogosphere.” Further conspirators, we are informed, include Brad DeLong and Tim Lambert. And of course one mustn’t omit the principal voice of RealClimate, Gavin Schmidt.

Perhaps I should feel personally honored to be included on Montford’s list of co-conspirators, because yours truly is also mentioned. According to Montford’s typical sloppy research I have styled myself as “Mann’s Bulldog.” I’ve never done so, although I find such an appellation flattering; I just hope Jim Hansen doesn’t feel slighted by the mistaken reference.

The conspiracy doesn’t end with the hockey team, climate researchers, and bloggers. It includes the editorial staff of any journal which didn’t bend over to accommodate McIntyre, including Nature and GRL which are accused of interfering with, delaying, and obstructing McIntyre’s publications.

Spy Story

The book concludes with speculation about the underhanded meaning of the emails stolen from the Climate Research Unit (CRU) in the U.K. It’s really just the same quote-mining and misinterpretation we’ve heard from many quarters of the so-called “skeptics.” Although the book came out very shortly after the CRU hack, with hardly sufficient time to investigate the truth, the temptation to use the emails for propaganda purposes was irresistible. Montford indulges in every damning speculation he can get his hands on.

Since that time, investigation has been conducted, both into the conduct of the researchers at CRU (especially Phil Jones) and Mike Mann (the leader of the “hockey team”). Certainly some unkind words were said in private emails, but the result of both investigations is clear: climate researchers have been cleared of any wrongdoing in their research and scientific conduct. Thank goodness some of those who bought in to the false accusations, like Andy Revkin and George Monbiot, have seen fit actually to apologize for doing so. Perhaps they realize that one can’t get at the truth simply by reading people’s private emails.

Montford certainly spins a tale of suspense, conflict, and lively action, intertwining conspiracy and covert skullduggery, politics and big money, into a narrative worthy of the best spy thrillers. I’m not qualified to compare Montford’s writing skill to that of such a widely-read author as, say, Michael Crichton, but I do know they share this in common: they’re both skilled fiction writers.

The only corruption of science in the “hockey stick” is in the minds of McIntyre and Montford. They were looking for corruption, and they found it. Someone looking for actual science would have found it as well.

581 Responses to “The Montford Delusion”

  1. 551
    Phil Clarke says:

    I see Mr McIntyre has got a whole post out of information that was published in Mann et al 2009, viz

    “”In addition to the tests described by ref. S1 which removed alternatively (a) all tree-ring data
    or (b) 7 additional long-term proxy records associated with greater uncertainties or
    potential documented biases (showing the temperature reconstruction was robust to
    removal of either of these datasets), we here removed both data sets simultaneously from
    the predictor network (Fig. S8). This additional test reveals that with the resulting
    extremely sparse proxy network in earlier centuries, a skillful reconstruction is no longer
    possible prior to AD 1500. Nonetheless, even in this case, the resulting (unskillful) early
    reconstruction remains almost entirely within the estimated error bounds of the original

    Must be a slow news day. I notice also that he seems to conflate the 7 potentially problematic datasets – which encompasses Tiljander, Benson, Isdale and McCulloch – and places all the ‘blame’ for the reduced skill before 1500AD on Tiljander alone. Sloppy.

    Perhaps worth repeating the IPCC paleo-summary

    “”Average Northern Hemisphere temperatures during the second half of the 20th century were very likely higher than during any other 50-year period in the last 500 years and likely the highest in at least the past 1,300 years. Some recent studies indicate greater variability in Northern Hemisphere temperatures than suggested in the TAR, particularly finding that cooler periods existed in the 12th to 14th, 17th and 19th centuries. Warmer periods prior to the 20th century are within the uncertainty range given in the TAR.”

    As you were.

  2. 552
    Phil Clarke says:

    Update: It has been pointed out at CA that the non-Tiljander proxies dropped as problematic do not extend back past 1500. Looks like Tiljander must shoulder the blame for the reduction in skill pre-1500. One could argue that this should have been made clear, however it was me who was sloppy, not Mr McIntyre.

  3. 553
    Phil Clarke says:

    But I was of course, correct in spirit, if not in actual detail ;-)

  4. 554
    MilanS says:

    Can Steve McIntyre respond to this post at your page? If yes, then I am going to believe that this is really about the science. Audiatur et altera pars …

  5. 555
    dhogaza says:

    Can Steve McIntyre respond to this post at your page? If yes, then I am going to believe that this is really about the science

    Science, re-defined in front of our very eyes …

  6. 556
    two moon says:

    #546 Ray Ladbury: Thanks for recommending Weart. For the record, I believe that evolution is “settled science” and I never heard of Velikovsky. “Which side is publishing” is not such a simple metric. It might only indicate which side has power. That’s why a common forum would, in my opinion, do much to restore trust. All the best, I’m out.

  7. 557
    Ray Ladbury says:

    Two Moon says, ““Which side is publishing” is not such a simple metric. It might only indicate which side has power.”

    Come on, Two Moon, do you really understand so little about science. Do you really think there is a massive conspiracy to suppress dissenters from the consensus? Do you really think that if the ideas of the dissenters had merit that they would not find a publication outlet–Nature, Science, JGR, PRL, EOS… Remember that what drives climate scientists–and what advances their careers–is a desire to understand climate. If the dissenters had anything worth saying, those who adopted their ideas would prosper, while those who rejected them would stagnate. Look who is publishing and look who is stagnating. It really is your best guide to truth in science.

  8. 558
    two moon says:

    #557 Ray Ladbury: In every other field of human endeavor the ability to be heard is a function of power. There is no reason that science should be an exception. One does not need to believe in any conspiracy to acknowledge this; it is a commonplace of modern (or rather, postmodern) social science. And in any case, if the dissenters’ case is so weak, then the most powerful and efficient way to quash them is to meet them in a common forum. Best regards.

  9. 559
    Doug Bostrom says:

    Ray Ladbury:

    Do you really think that if the ideas of the dissenters had merit that they would not find a publication outlet–Nature, Science, JGR, PRL, EOS…

    Anyway, assuming there were somehow the ability to suppress papers by tacit agreement among a plethora of individuals with disparate if not competing interests, the time when that was possible ended arguably 15 years ago. Particularly in this arena of investigation any “outsider” work would not lay hidden for long; there are ample facilities for publishing outside of “official channels.” To wit, the various contrarian carney shows, whose often freakish array of alternative perspectives are nonetheless inevitably scrutinized to the point of absurdity thanks to their enthusiasts’ proclivity for redundant presentation wherever actual scientists may be found to tap on the shoulder.

  10. 560
    dhogaza says:

    two moon:

    And in any case, if the dissenters’ case is so weak, then the most powerful and efficient way to quash them is to meet them in a common forum.

    Well, yes, they’re met in a “common forum” known as the scientific press. If their work is sufficiently shoddy, they’re shown the door – before publication.

    That is how it should be. You may argue all you want that the earth has two moons, two moon, but you’re not going to get your hypothesis past the gatekeepers of the scientific press. Again, as it should be.

  11. 561
    Patrick 027 says:

    Re 558 two moon –
    if the dissenters’ case is so weak, then the most powerful and efficient way to quash them is to meet them in a common forum. Best regards.

    It would waste (assuming the goal is not satire) too much space to put research articles in publications proving the moon is made of cheese (it’s got craters, Swiss cheese has holes, by Glen Beck style logic: ergo…) or that the moon landings were faked or that the Earth is flat, or that purified water can do magic, or that you can get jewelry by staring at it through a shop window, or that a bacterial flagellum could not have evolved, – you know, common sense stuff like that…

    G&T managed to get their work out there; publishing it in Nature or Science would not have changed the fact that they’re arguments just don’t hold any water (they didn’t do any new science, they just took what was already known, and then tried to use that to argue against what is already known – a search for logical inconsistency, which might have been worthwhile if they’d known what they were doing and if they’d gone after contrarian ‘theory’) – unless it were edited, removing all the errors and non-sequitors, after which it would be no different than a physics book such as the kind a climate scientist would use…

    Point being, we don’t always need to wait for work to be published in a particular forum to know that it’s worthless. The more obvious junk generally tends not to get into quality publications.

  12. 562
    Hank Roberts says:

    > the most powerful and efficient way to quash them

    Because as we all know, the green party runs the world

    That’s one of “the 50 best science blogging posts of the year” from

  13. 563
    Hank Roberts says:

    The key quote from that link:

    \Yes, there are mafias. There are those spared the kicking because they have connections. There are established cliques who decide what appears in Science, who gets to give a spoken presentation and who gets kicked down to the poster sessions with the kiddies. I know a couple of people who will probably never get credit for the work they’ve done, for the insights they’ve produced. But the insights themselves prevail. Even if the establishment shoots the messenger, so long as the message is valid it will work its way into the heart of the enemy’s camp. First it will be ridiculed. Then it will be accepted as true, but irrelevant. Finally, it will be embraced as canon, and what’s more everyone will know that it was always so embraced, and it was Our Glorious Leader who had the idea. The credit may not go to those who deserve it; but the field will have moved forward.

    Science is so powerful that it drags us kicking and screaming towards the truth despite our best efforts to avoid it. And it does that at least partly fueled by our pettiness and our rivalries. Science is alchemy: it turns shit into gold. Keep that in mind the next time some blogger decries the ill manners of a bunch of climate scientists under continual siege by forces with vastly deeper pockets and much louder megaphones.\

  14. 564
    Michael says:

    Gavin, you’ll be pleased to hear furhter from Judith Curry.

    Apparently you’re all doing “shoddy science”.

    And she knows this because she’s getting emails from engineers and the like how tell her that they “don’t believe” in the confidence levels claimed by climate researchers, because, well, they just don’t believe it.

    Judith has outdone herself.

    Go and have a read over at Kloor’s….. if you can bear it.

  15. 565
    Ray Ladbury says:

    Two Moon,
    In science, the ability to be heard is also a function of power–explanatory and predictive power. If your ideas do a better job of explaining the evidence and providing understanding of the subject, they will be heard. Those who adopt them early will prosper. Those who reject them will fail. Those of us who actually work in science know this is how it works. And we also know that it does in fact work. By all means apply social theory to science, but understand the frigging community you are applying it to–their motivations, values, etc.

    Or you can simply apply the maxim of a much more astute observer of human nature–the people and groups act in accord with their perceived interests. In this case, the interests of the scientific community are furthered by increased understanding of their subject matter. Telling the truth is in their own interest.

  16. 566
    Silk says:

    “This matter cries out for a common public forum–even a series of face-to-face encounters”

    What? Like the IPCC?

    There /is/ a global forum where Climate Science is discussed. It’s got quite a few publications, you know.

  17. 567
    Radge Havers says:

    two moon @ 558

    “In every other field of human endeavor the ability to be heard is a function of power. There is no reason that science should be an exception.”

    Why? Just because you can’t think of a reason?

    “One does not need to believe in any conspiracy to acknowledge this; it is a commonplace of modern (or rather, postmodern) social science.”

    There’s power and then there’s power. Power in science comes largely from doing good science. That’s because the social structures supporting science are more tightly focused on promoting merit. There are exceptions, for example review the Sokal affair. Then just for larfs, swing on over to pomo and get down with some postmodern silliness.

    “And in any case, if the dissenters’ case is so weak, then the most powerful and efficient way to quash them is to meet them in a common forum.”

    Yeah right, because cynically created memes don’t take root in poorly informed peoples’ heads like kudzu. Naive.

  18. 568
    dhogaza says:

    Regarding Judith’s appearance at Keith Kloor’s (there’s a follow-on interview with Gavin), she at least admits this:

    Doing drive-bys at other blogs is very hazardous (e.g. my drive by last week at RC).

    Well, Judy, the problem wasn’t so much doing a drive-by, but rather posting a drive-by full of factual error, then showing up again in a hissy fit when the errors were pointed out.

    It’s obvious she still doesn’t understand that the car wreck that resulted was a single-car accident with her at the wheel.

  19. 569
    Doug Bostrom says:

    The interviews dghoza points out are pretty useful for assessment purposes.

    Gavin Schmidt

    Judith Curry

    A coherent synopsis, way better than fragmented discussion on multiple websites, helpful for discerning between offers of judicious, circumspect advice, claims founded on evidence.

  20. 570
    two moon says:

    #567 Radge Havers: I assume that you refer to “Fashionable Nonsense” by Alan Sokal and Jean Bricmont. It has an honored place in my library. And thank you for reinforcing my point: Sokal and Bricmont’s targets would similarly claim that authentic understanding of their disciplines exists exclusively within their peer-reviewed community. I do not believe that Sokal’s targets and climate scientists are on the same level; climate scientists make an incomparably more valuable contribution. The broader point remains nonetheless valid in my view: without a common forum for direct engagement with their critics, climate scientists risk continued erosion of public trust.

  21. 571
    ccpo says:

    570 @twomoon: “The broader point remains nonetheless valid in my view: without a common forum for direct engagement with their critics, climate scientists risk continued erosion of public trust.”

    I submit the engagement will remain relatively ineffective outside of two things: undeniable crisis (meaning something even Joe Average Just Let Me Get Through The Week would realize is some serious #$#$) and or a response similar to that given to Monckton of late.

    We simply are not wired to worry about very long term issues. Nate Hagen has written a good bit about discount rates at

    Thus, a little bit of beating over the head will be necessary. This has been well demonstrated by the presence of blogs such as RC during the same period when understanding of climate science and ACC actually declined seriously. While that decline is largely the result of inappropriate actions on the parts of a relatively small group of ideologues and their followers (who are only too willing to accept what the ideologues say due to the Discount Rate), it has still happened.

    It will take some serious %^&* to get past the hard wiring we have.


  22. 572
    John Mashey says:

    re: #570 Two moon
    Let me an offer an analogy to what you’re saying.
    Medical researchers have published much research in peer-reviewed journals that strongly indicate linkage of smoking with disease. However, biology is a lot complex than the sophomore physics (conservation of energy, GHG behavior) behind AGW. If your 12-year-old (kid, grandkid) starts smoking regularly, nobody can predict whether or not they’ll die of luing cacner, heart disease, or whatever, or when. Folks like Steve Milloy are critics of the general medical conclusion. Therefore, until medical researchers are regularly willing to meet Milloy (and friends) in common forums and direct engagement, our trust in those researchers should erode, presumably to the point where you encourage any children or grandchildren to start smoking early, it’s good for the local economy. Also, the likelihood of death from smoking-related disease is lower than that of AGW problems, for most people.
    Meanwhile, if you’d like to get more informed on the organization behind the critics, try this. You will understand that the cigarette analogy was no accident. For example, apparently you would claim that scientists should meet Joseph Bast, whose job for years was helping tobacco companies, meaning helping them addict kids. Tobacco funding is down, so in last few years he’s been doing the adjacent market of climate anti-science, using all teh PR machinery and contact lists built over decades.

  23. 573
    Steve Metzler says:

    two moon (#570):

    The broader point remains nonetheless valid in my view: without a common forum for direct engagement with their critics, climate scientists risk continued erosion of public trust.

    It’s been tried and it doesn’t work. The well-intentioned posters who have substantive contributions to make get drowned out by the denialist Noise Machine™. Once McIntyre or Watts’ legions get wind of a forum discussion on AGW, it needs to be heavily moderated. They are just drones that ceaselessly regurgitate denier canards that have been debunked time and time again.

    reCaptcha: insights starved (how apropos!)

  24. 574
    Radge Havers says:

    two moon @ 570

    “The broader point remains nonetheless valid in my view: without a common forum for direct engagement with their critics, climate scientists risk continued erosion of public trust.”

    Not much for me to add to the follow-up by other posters other than a) to point out the obvious that RC and quite a number of other sites already do a stellar job of presenting broad, interactive straight talk on climate and b) offer a little conjecture on my part.

    There is a even broader issue of how public discourse on a whole spectrum of issues, including climate, is being purposely polluted by propaganda and demagoguery. For example, critics often point to the role of the FCC and how some of its political appointees have, over the years, permitted consolidation of media outlets–to the effect that the free exchange of ideas has been stifled and respect for thoughtful analysis has been undermined. It may be worth examining those kinds of structural issues over blindly advocating a theory that turning all discussions into a kind of verbal mud wrestling will somehow sort it all out for the best. What’s fittest in that instance may also turn out to be what’s most perniciously idiotic.

  25. 575
    Steve Metzler says:

    Oh wait though… there may be a way. How about a special forum where certain individuals are invited to post, *unmoderated*. They are given a password. The general public can’t post, but they can read all the interchanges between the climate scientists and the invited skeptics.

    I think that would fly. And it could be hosted on any forum, even here, because it can’t be hijacked by people that haven’t been invited to participate.

  26. 576
    Doug Bostrom says:

    “The broader point remains nonetheless valid in my view: without a common forum for direct engagement with their critics, climate scientists risk continued erosion of public trust.”

    Ignoring that a vanishingly small fraction (anybody care to guess?) of people actually bother to read any of this stuff. How decimal places out is this group?

    As an experiment, travel to various climate blogs, look at the names in comments, see just how microscopic this community really is.

    If there’s utility to comments on climate blogs, it’s in keeping track of whatever rubbish has been most recently launched into the larger and actually significant world of George Will etc.

  27. 577
    tempterrain says:

    Is the Judith Curry who was recently involved in a sharp exchange of words with Gavin Schmidt the same Judith Curry who in October 2007 wrote in the Washington Post

    “In his Outlook essay “Chill Out,” Bjorn Lomborg rightly notes that skepticism about climate change is no longer focused on whether it the earth is getting warmer (it is) or whether humans are contributing to it (we are). The current debate is about whether warming matters, and whether we can afford to do anything about it.

    In this debate, Lomborg has positioned himself squarely in the skeptics’ camp. But he has some of his facts wrong — and he fails to appreciate the risks that global warming bring to us all.

    On the facts, Lomborg writes that the Kangerlussuaq glacier in Greenland is “inconveniently growing,” somehow undercutting the argument that the world is getting warmer. But NASA research shows that Greenland’s Kangerlussuaq glacier is not growing; it is simply spilling into the sea.

    Lomborg also misrepresents some conclusions of the U.N.’s Intergovernmental Panel on Climate Change. He is skeptical about the claim that polar bears “will be decimated by global warming as their icy habitat melts.” But the report shows that, even under the best-case scenario, about two-thirds of the current polar bear population will be lost by 2050.

    Lomborg’s attitude toward risk is also troubling. He focuses only on the middle range of the panel’s projections, dismissing the risk from the higher end of the range. But if the risk is great, then it may be worth acting against even if its probability is small. Think of risk as the product of consequences and likelihood: what can happen and the odds of it happening. A 10-degree rise in global temperatures by 2100 is not likely; the panel gives it a 3 percent probability. Such low-probability, high-impact risks are routinely factored into any analysis and management strategy, whether on Wall Street or at the Pentagon.

    The rationale for reducing emissions of carbon dioxide is to reduce the risk of the possibility of catastrophic outcomes. Making the transition to cleaner fuels has the added benefit of reducing the impact on public health and ecosystems and improving energy security — providing benefits even if the risk is eventually reduced.

    In his cost-benefit analysis, Lomborg considers only one policy option for reducing carbon emissions — the Kyoto Protocol — and says its worldwide cost would be about $180 billion per year. But the debate over the economics of global warming is more wide-ranging than Lomborg would have it. More than a dozen different studies have examined the economic impact of Kyoto-level controls. Some have concluded that it could have relatively small negative effects, such as those cited by Lomborg. Others have predicted small positive effects. Moreover, by focusing only on the Kyoto Protocol, Lomborg ignores potentially better policies that could cost far less than Kyoto and deliver higher economic growth worldwide.

    Lomborg gets it right when he calls for an ambitious public investment program in clean-energy technologies. But he mistakenly assumes that existing technologies and strategies can’t make a big dent in carbon emissions at an affordable price. We’re developing hybrid and electric cars, building wind farms and ocean wave energy stations. New batteries, fuel cells and solar panels are smaller, better and cheaper than they were just a few years ago. I am in awe of the new technologies that I see being developed at Georgia Tech, and such research is happening at the nation’s major research universities and in the private sector.

    As scientists continue to challenge and improve the quality and understanding of climate records and models, skepticism by scientists conducting such research is alive and well. But oversimplifying the situation, using misleading information and presenting false choices is not useful in the public debate over global warming.

    Lomborg seems to have missed it, but a sensible debate has begun on how to best respond to global warming – in national and local governments, universities and the private sector — in the U.S. and around the world. There is no easy solution to this problem; the challenge is how best to develop options that are feasible, efficient, viable and scalable. Lomborg is correct to be concerned about the possibility of bad policy choices. But I have yet to see any option that is worse than ignoring the risk of global warming and doing nothing.”

  28. 578
    melty says:

    “Thank goodness some of those who bought in to the false accusations, like Andy Revkin and George Monbiot, have seen fit actually to apologize for doing so.”

    Can anyone point me to the place where Andy apologizes? I must have missed it.

  29. 579
    Chris Watkins says:

    Haven’t posted here before. I’ve read a few hundred of the previous posts but not all of them, and I’m obviously late to the party :)

    I have a question.

    The papers I’ve seen (which I’m sure are not all the relevant ones :) ) from MBH98 through to WA2007, all seem based on PCA. There are intricate on deciding how many principal components to retain before regressing against temperature….hmmm.

    Erm…these methods seem just a tad old-fashioned now. Has anyone done a Bayesian analysis, which would enable using different error models, and testing out models that, for example, might even cope with intermittently unreliable proxy series, in a principled way? Given that these reconstructions involve combining multiple series of different lengths with (presumably) different types of errors, and possibly time-varying reliability, … I’m assuming that a wider range of statistical techniques have actually been tried?

  30. 580
    Doug Bostrom says:

    Heavily freighted w/political commentary and dog whistle assertions without cites such as “natural climate variability is not well understood and is probably quite large” though it is, can anybody w/expertise offer some commentary on this paper by a pair of B-school profs?

    A statistical analysis of multiple temperature proxies: Are reconstructions of surface temperatures over the last 1000 years reliable?

    It’s the fad du jour at WUWT. Notably circulated and celebrated even though apparently not yet quite published.

  31. 581
    apeescape says:

    Chris Watkins,

    AFAIK, Mann et al. (2008) also uses a screening out process that weeds out proxies of a certain time period that doesn’t correlate well w/ instrumental records (which is different from PCA in reducing overfitting). And yes, they do cross-validate estimation methods with each other.

    I’m sure RC will get to this, but there is a new paper out by McShane and Wyner (two statisticians) for the Annals of Applied Scientists that says the uncertainty in the “hockey stick” is understated.