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Hey Ya! (mal)

Filed under: — group @ 30 September 2009

Interesting news this weekend. Apparently everything we’ve done in our entire careers is a “MASSIVE lie” (sic) because all of radiative physics, climate history, the instrumental record, modeling and satellite observations turn out to be based on 12 trees in an obscure part of Siberia. Who knew?

Indeed, according to both the National Review and the Daily Telegraph (and who would not trust these sources?), even Al Gore’s use of the stair lift in An Inconvenient Truth was done to highlight cherry-picked tree rings, instead of what everyone thought was the rise in CO2 concentrations in the last 200 years.

Al Gore apparently confusing a CO2 curve for a tree

Who should we believe? Al Gore with his “facts” and “peer reviewed science” or the practioners of “Blog Science“? Surely, the choice is clear….

Yamal sub-fossil larch trees in river sedimentMore seriously, many of you will have noticed yet more blogarrhea about tree rings this week. The target de jour is a particular compilation of trees (called a chronology in dendro-climatology) that was first put together by two Russians, Hantemirov and Shiyatov, in the late 1990s (and published in 2002). This multi-millennial chronology from Yamal (in northwestern Siberia) was painstakingly collected from hundreds of sub-fossil trees buried in sediment in the river deltas. They used a subset of the 224 trees they found to be long enough and sensitive enough (based on the interannual variability) supplemented by 17 living tree cores to create a “Yamal” climate record.

A preliminary set of this data had also been used by Keith Briffa in 2000 (pdf) (processed using a different algorithm than used by H&S for consistency with two other northern high latitude series), to create another “Yamal” record that was designed to improve the representation of long-term climate variability.

Since long climate records with annual resolution are few and far between, it is unsurprising that they get used in climate reconstructions. Different reconstructions have used different methods and have made different selections of source data depending on what was being attempted. The best studies tend to test the robustness of their conclusions by dropping various subsets of data or by excluding whole classes of data (such as tree-rings) in order to see what difference they make so you won’t generally find that too much rides on any one proxy record (despite what you might read elsewhere).

****

So along comes Steve McIntyre, self-styled slayer of hockey sticks, who declares without any evidence whatsoever that Briffa didn’t just reprocess the data from the Russians, but instead supposedly picked through it to give him the signal he wanted. These allegations have been made without any evidence whatsoever.

McIntyre has based his ‘critique’ on a test conducted by randomly adding in one set of data from another location in Yamal that he found on the internet. People have written theses about how to construct tree ring chronologies in order to avoid end-member effects and preserve as much of the climate signal as possible. Curiously no-one has ever suggested simply grabbing one set of data, deleting the trees you have a political objection to and replacing them with another set that you found lying around on the web.

The statement from Keith Briffa clearly describes the background to these studies and categorically refutes McIntyre’s accusations. Does that mean that the existing Yamal chronology is sacrosanct? Not at all – all of the these proxy records are subject to revision with the addition of new (relevant) data and whether the records change significantly as a function of that isn’t going to be clear until it’s done.

What is clear however, is that there is a very predictable pattern to the reaction to these blog posts that has been discussed many times. As we said last time there was such a kerfuffle:

However, there is clearly a latent and deeply felt wish in some sectors for the whole problem of global warming to be reduced to a statistical quirk or a mistake. This led to some truly death-defying leaping to conclusions when this issue hit the blogosphere.

Plus ça change…

The timeline for these mini-blogstorms is always similar. An unverified accusation of malfeasance is made based on nothing, and it is instantly ‘telegraphed’ across the denial-o-sphere while being embellished along the way to apply to anything ‘hockey-stick’ shaped and any and all scientists, even those not even tangentially related. The usual suspects become hysterical with glee that finally the ‘hoax’ has been revealed and congratulations are handed out all round. After a while it is clear that no scientific edifice has collapsed and the search goes on for the ‘real’ problem which is no doubt just waiting to be found. Every so often the story pops up again because some columnist or blogger doesn’t want to, or care to, do their homework. Net effect on lay people? Confusion. Net effect on science? Zip.

Having said that, it does appear that McIntyre did not directly instigate any of the ludicrous extrapolations of his supposed findings highlighted above, though he clearly set the ball rolling. No doubt he has written to the National Review and the Telegraph and Anthony Watts to clarify their mistakes and we’re confident that the corrections will appear any day now…. Oh yes.

But can it be true that all Hockey Sticks are made in Siberia? A RealClimate exclusive investigation follows:

We start with the original MBH hockey stick as replicated by Wahl and Ammann:

Hmmm… neither of the Yamal chronologies anywhere in there. And what about the hockey stick that Oerlemans derived from glacier retreat since 1600?

Nope, no Yamal record in there either. How about Osborn and Briffa’s results which were robust even when you removed any three of the records?

Osborn and Briffa (2006) Supplemental Material

Or there. The hockey stick from borehole temperature reconstructions perhaps?

No. How about the hockey stick of CO2 concentrations from ice cores and direct measurements?

Err… not even close. What about the the impact on the Kaufman et al 2009 Arctic reconstruction when you take out Yamal?

Oh. The hockey stick you get when you don’t use tree-rings at all (blue curve)?

M08

No. Well what about the hockey stick blade from the instrumental record itself?

And again, no. But wait, maybe there is something (Update: Original idea by Lucia)….

Nah….

One would think that some things go without saying, but apparently people still get a key issue wrong so let us be extremely clear. Science is made up of people challenging assumptions and other peoples’ results with the overall desire of getting closer to the ‘truth’. There is nothing wrong with people putting together new chronologies of tree rings or testing the robustness of previous results to updated data or new methodologies. Or even thinking about what would happen if it was all wrong. What is objectionable is the conflation of technical criticism with unsupported, unjustified and unverified accusations of scientific misconduct. Steve McIntyre keeps insisting that he should be treated like a professional. But how professional is it to continue to slander scientists with vague insinuations and spin made-up tales of perfidy out of the whole cloth instead of submitting his work for peer-review? He continues to take absolutely no responsibility for the ridiculous fantasies and exaggerations that his supporters broadcast, apparently being happy to bask in their acclaim rather than correct any of the misrepresentations he has engendered. If he wants to make a change, he has a clear choice; to continue to play Don Quixote for the peanut gallery or to produce something constructive that is actually worthy of publication.

Peer-review is nothing sinister and not part of some global conspiracy, but instead it is the process by which people are forced to match their rhetoric to their actual results. You can’t generally get away with imprecise suggestions that something might matter for the bigger picture without actually showing that it does. It does matter whether something ‘matters’, otherwise you might as well be correcting spelling mistakes for all the impact it will have.

So go on Steve, surprise us.

Update: Briffa and colleagues have now responded with an extensive (and in our view, rather convincing) rebuttal.


759 Responses to “Hey Ya! (mal)”

  1. 401
    dhogaza says:

    To conflate disagreement and dishonesty, to me, is a dull rhetorical axe.

    Well, there are only two possibilities for disagreement on something as basic as this:

    1. absolute ignorance of statistics

    2. dishonest

    Since you are offended by Ray’s having chosen #2, that leaves us with #1. Rather than disagreeing, why not go learn a bit so you understand that this is the statistical equivalent of stating that 2+2 equasl 4, and there’s no room for “disagreement”.

  2. 402
    dhogaza says:

    In both cases the .2C per decade temperature increase that you would expect from the CO2 increase is missing.

    Tilo Reber, you know very well that climate science does not claim that temperatures will increase 0.2C every decade in monotonically increasing style, that natural variability is known about and acknowledged within climate science, and that all that’s stated is in terms of statistically valid, long-term trends.

    Building strawmen versions of science to knock down is nothing short of lying.

  3. 403
    Cumulus says:

    Ray #394, I mostly agree with your comments. There needs to be a permanent group out there, some third party, to which scientists can go and have the data or methods in controversial papers reviewed/audited in **private**. Such a group would be comprised of independent experts in the relevant field. Upon conclusion of the investigation they would release their findings in a report for all to see. That is one, ethical and fair way, to conduct an audit.

    Anyhow, I’m not sure where the confusion crept in with my earlier message, probably me, I’m tired and wasn’t making myself clear. Please go and try and tell the “group think” at ClimateAudit what you just told us here. The auditing of these sensitive and complex issues in the public forum, nay the internet of all places, is ludicrous and destined to end in a circus. McIntyre will deny that until he is blue in the face, but that is the reality. Truth is, he probably wants a fiasco, how can people take AGW seriously when it is in the middle of a circus? Doesn’t matter if the allegations are wrong, doesn’t matter if they do not change the conclusions of the research. The idea is to caste doubt and undermine the credibility of the science.

    I think someone should ask for McIntyre to have his income taxes audited for all to see in the public forum. All of it, including everyones opinions and what he may have done wrong, or could have done, or should have done. Even if there was no wrong doing, at the end of the day he would look bad. That would not be right, it would not be fair, but if was someone’s intention to cast doubt on his credibility, they would have succeeded.

    Now I’m not seriously suggesting that someone do that. But I hope people get the analogy that I am trying to make here.

    NB: Ray, I urge you and Tom P to please contact the National Post and express your concerns and views on this matter (see my earlier post for their contact details). They really do need to get the message.

  4. 404
    Mark P says:

    Gavin

    Interesting article. Stripping away the hyperbole, ad-hominems, debates on the scientific method and the merits of archiving data on both sides of the debate, I just want to ask some specific, clear questions about the Briffa (2000) paper and McIntyre’s allegations.

    My understanding is that McIntyre has made a specific criticism of the science in the Briffa (2000) paper. His criticism is that the tree core sample set used in the calibration period is statistically poor. He further alleges that this significantly weakens the scientific conclusions of the Briffa (2000) paper. More specifically, he seems to make the following criticisms of Briffa (2000):

    1) In the calibration period, too few tree cores are used. He alleges at http://www.climateaudit.org/?p=7142 that”The counts decline from 24 in 1956 to only 10 in 1990 and 5 in 1995-96″. He further claims at http://www.climateaudit.org/?p=7257 that this is too few to be statistically valid given the RCS method used in Briffa (2000): “… it was not of an adequate size in the modern period for Briffa’s RCS standardization”.

    [Response: I'm not a tree ring person, so my opinion on this is perhaps not worth much, but RCS creates one single tree-ring growth curve for the area, which is used to detrend all the trees. I can certainly see that having enough trees to calculate the growth curve would be cruical, but once that is defined, you can apply it to as many or as few as you want. Thus the claim that 10 or 12 trees is too few for one particular portion seems a step too far. Obviously more is better, but whether 10 or 12 is enough depends on what uncertainty level you are ok with. It isn't going to be a hard and fast rule. - gavin]

    2) The calibration tree cores appear highly atypical compared with the rest of the sample population. They are at the upper end of the age range and some of them show statistically extreme growth spurts in recent times. At http://www.climateaudit.org/?p=7241 he states “There is a profound inhomogeneity in the age composition of the living trees in the [Briffa (2000)] CRU archive relative to the subfossil archive” and on the same thread he shows example of growth spurts in some of the trees.

    [Response: If you look at the fossil trees you will see similar things, and of course there is a systematic issue related to sampling living trees that might well be younger on average than the fossil ones. Tom P. above showed that the Yamal curve was robust to homogenising the age structure, and frankly I have a lot more confidence in Keith Briffa to do this right than I have in McIntyre. - gavin]

    Your article above and Briffa’s response here http://www.cru.uea.ac.uk/cru/people/briffa/yamal2000/ both seem to focus on the ad-hominem parts of McIntyre’s threads, ie they address the implied allegation of cherry-picking of the calibration set. While this may be interesting, it does not in my view address McIntyre’s specific scientific criticisms of the calibration set which I have tried to summarise above.

    [Response: Perhaps you will notice that it is the implied allegations that were objectionable. No-one has any problem with McIntyre making his own chronologies or his own reconstructions as long as the decisions he makes about what to include or not and how to process the data is sound and properly described in a paper. - gavin]

    Questions to you, Gavin. Do these specific criticisms of the science in Briffa (2000) have any merit? If they are without merit, what are the specific rebuttal points which defend Briffa (2000) against them? If they do have some merit, how much do they weaken the scientific conclusions of the Briffa (2000) paper?

    [Response: I doubt very much that the issue raised have much merit. That reconstruction was the one that was made with that source material. With more source material (which is apparently being processed and added in) the chronology will change somewhat I suppose, but I'm happy to wait and see what comes out. - gavin]

    Just to be clear, I am not interested in
    - ad hominem answers (motivations, accusations of cherry picking, etc)
    - defences based on the fact that other scientific studies produce similar results to Briffa 2000,
    - discussions of what calibration set pre-selection or pre-processing might or might not have been done, and whether it was or was not valid. If it is not explicitly mentioned in Briffa (2000) or other contemporaneous referenced material then I’m not interested in it.

    I am genuinely trying to understand the science behind dendroclimatology, but I often struggle to find the science behind the personalities – I hope your reply can help me.

    Mark

  5. 405
    Ray Ladbury says:

    Walter Manny, OK, what would you call it when someone KNOWINGLY uses a time series too short to be representative and draws conclusions for a LAY audience who is not sufficiently sophisticated to recognize the invalidity of the exercise. Personally, I think dishonesty is a charitable label. It borders on criminal fraud.

  6. 406

    Walter, the point is that there are statistical tests for significance. If those are too much trouble, there are rules of thumb, such as the “30-year climatological trend” idea, which is floating around.

    But if you’re fussing about with trends at 111 versus 120 months, do you really feel that that is an “honest” endeavor? A significant endeavor? And just which group of people keeps harping on this short timeline, anyway?

    Responding to these (IMO, foolish) claims doesn’t add up to “trying to have it both ways.”

  7. 407
    ghost says:

    RE: Barton’s post 376 “What part of “cosmic ray flux has shown no trend for 50 years while temperatures have increased sharply….”, I have not yet seen a denial theory trumpeted to the effect that ‘temperature simply lags cosmic flux by about 50 years, as illustrated by this graph of the past…50 years’ but I imagine it is/will be out there somewhere.

    On the general denial topic, if we are able to reduce GHGs enough to slow AGW, then the continuing cry will be ‘See–the temperature is cooling, so AGW never existed. That SOB Al Gore cost us a lot of money for nothing.’ We’ve seen the same spin about Y2K–’they got all cry-wolfed up about Y2K problems, and they never happened, so it was just a bunch of hysteria’ (ignoring the massive commitment of money, time, and personnel that was responsible for avoiding the problem.’) In a way, the short-circuit about hurricane warnings is similar–’the government said Hurricane X could be deadly, but looky here, the hurricane landed, but no one died. They scared the residents for nothing.’ (Nevermind that the reason no one died is that everybody evacuated the area.)
    On the general denial topic, if we are able to reduce GHGs enough to slow AGW, then the cry will be ‘See–the temperature is cooling, so AGW never existed.’

  8. 408

    #396 Walter Manny

    Here is where you and yours get yourselves into the soup:

    Actually, your reply is more easily connotatively rhetoric, while Ray is more clearly and connotatively described as responsive, informative and descriptive.

    http://www.merriam-webster.com/dictionary/rhetoric

    How is your statement not dishonest?

    http://www.merriam-webster.com/dictionary/dishonest

    In other words, since your statement is not trustworthy with regard to relevant context, why would anyone trust if, i.e. the statement/implication that the last 10 years (or whatever) is flat is dishonest when weighed in consideration of the overall warming trend caused by human contributions to greenhouse gases. You can of course use the lame argument that you only meant to discuss the short term, but it is a ridiculously weak, even pathetic, argument…, considering the fact that you already know 10 years is meaningless in the context of AGW.

    How is being honest about other peoples dishonesty a bad thing? Or are you going to claim that those bloggers in RC are mean because they are attacking my dishonesty with honesty?

    If what you are representing is not representing honestly the relevant perspective, it is dishonest.

  9. 409
    Richard Sycamore says:

    Tom P’s analysis is intriguing. Perhaps he can write it up in full so that we can benefit from the wisdom of his insight?

  10. 410
    Eli Rabett says:

    For the Yamal thread:

    CTG at 389 asks if the auditors have been audited. Been there, done that

    BTW, Nigel is Steve in drag. Something that would have been useful to know.

  11. 411
    Hank Roberts says:

    The ‘emeritus effect’ has been quantified:
    http://www.nature.com/naturejobs/2009/091001/full/nj7264-681a.html

    Likely the same applies to auditors.
    This is a strong argument for having many journals, many reviewers, and for that matter many, many auditing firms — not only a few large ones that can be dominated by older people who have lost their edge and critical sense.

    It’s, as one person interviewed in the article says, rather depressing if you’re among the older people, but we knew it happened.

    It’s good news for the younger people coming up who still have their critical edge on.

  12. 412
    Deep Climate says:

    #404
    Good to see some of the issues with McI’s analysis coming out.

    Meanwhile, I’m having trouble posting here on my analysis of McIntyre’s evolving charges of cherry-picking. Some of the outrageous language (reference to addicts etc.) he used is getting caught in the spam filter.

    http://deepclimate.org/2009/10/04/climate-auditor-steve-mcintyre-yamal/

  13. 413
    Hank Roberts says:

    > in drag
    As in using a sock puppet? Just to be clear.

    [Response: Tim Lambert at Deltoid has looked into this before. - mike]

  14. 414
    EW says:

    Cumulus said:
    http://www.realclimate.org/index.php/archives/2009/09/hey-ya-mal/comment-page-8/#comment-137195

    I can understand that they are frustrated after having to wait almost 10 years, but why should anyone be under any obligation to release their data for public audit by a private individual on the internet of all places?
    This may be a new concept for you, but for e.g., in the phylogenetic studies based on DNA sequences, the said sequences, all software used for processing and the parameters of the analyses, often with the whole input files, must be archived prior even submitting the paper in the completely open internet databases as GenBank and Treebase. Otherwise it would not be even considered for submission.
    So, if anyone wants to check the calculations, be it a private individual, or a colleague working in the field, they can. Even most of the software is open source.

  15. 415
    Hank Roberts says:

    Erm, if you look at Eli’s link to the old Usenet info, don’t click the link in that page to “climate2003.com” without your Javascript guard up; it appears to me that the URL is in the hands of one of those superficially convincing marketing companies that puts up a maze of endless links to stuff, or worse.

    Just googling for doublequote Steve McIntyre doublequote space doublequote Nigel Persaud doublequote finds ample documentation of the sockpuppetry.

    Aside: at least where I live, being ‘in drag’ is unlike a sock puppet in every way — not lying, not deceptive, and fun to be around. Theater, not bunkum.

  16. 416
    Ron Broberg says:

    re47:

    Gavin,

    I want to publicly thank NASA/GISS for putting source code for GISTEMP and ModelE online. I am one of those that have downloaded the code. I was able to compile the code on an Ubuntu Linux system with some additional downloads. Except for ‘step 5′ in GISTEMP. Had some problems there.

    Having access to the code was a cool treat for me. Made me look much closer into the published accounts of GISTEMP and USHCN. It help educate me. It made me a better advocate for AGW science.

    And maybe I’ll be able to crack ‘step 5′ yet! :-)

    With sincere thanks.

  17. 417
    Mark P says:

    Gavin

    Thanks for your response. I appreciate your time, your response raises a few more questions for me:

    >> I can certainly see that having enough trees to calculate the growth curve would be cruical, but once that is defined, you can apply it to as many or as few as you want. Thus the claim that 10 or 12 trees is too few for one particular portion seems a step too far. Obviously more is better, but whether 10 or 12 is enough depends on what uncertainty level you are ok with. It isn’t going to be a hard and fast rule. – gavin

    I disagree, there IS going to be a hard and fast rule. McIntyre refers to a paper [Bunn et al, Tree Ring Research Vol 60(2)] which shows some evidence that the RCS method is weak with small numbers (15) of trees unless the signal amplitude is very large. What test does Briffa (2000) apply to its calibration set during the RCS process, and does its 12 tree set pass this test?

    [Response: Knowing what Briffa (2000) does or does not do would be best served by reading Briffa (2000) and not asking me. Similarly, understanding Bunn et al is best started by reading Bunn et al (online here). In it you will find that the statement about numbers is related to the construction of the RCS growth curve (for which a minimum of 15 trees was suggested). This is exactly in line with my previous comment and does not support your contention in the slightest. To quote (my highlighting):

    The RCS method is sensitive to the number of series used to generate the regional curve. If the model runs containing 15 trees are subset (115 of the 10,000 models runs), then the mean coherency between the input signals and the RCS chronology for the multi-centennial time scales is 0.76.

    I should once again point out that I don't know very much about tree rings - though I am capable of checking references. - gavin]

    >> Tom P. above showed that the Yamal curve was robust to homogenising the age structure,

    Tom P has done some great work – kudos to him for doing so. But I think he’s on the wrong track. McIntyre alleges that the calibration trees are atypical compared with the total data set. He appears correct – they are atypical at least as far as age goes. Tom P has demonstrated that making the rest of the data set atypical in the same way has little impact on the results. Fair enough. But that absolutely does not address the criticism of the calibration trees. Given what we know about the entire Yamal data set, the calibration trees are still atypical. Making the rest of the data set atypical won’t help that. We are still left with questions:- Does Briffa (2000) mention the atypicality of the calibration trees? If not, why not? If it does, how does it compensate for their atypicality, or does it show that it doesn’t matter?

    As an aside Tom has shown that the results are highly sensitive to the calibration trees:- removing a single tree out of the 250-plus in the sample set has a significant impact on the Briffa (2000) results. It reduces the hockey stick height from about 2.75 units to about 2.35. That’s about 20% of the entire result attributable to one out of the 250 plus trees in the sample. Does Briffa (2000) test the robustness of its results to the type, or number of the calibration trees? Does the fact that Briffa (2000) results shows significant variation with the removal of just one tree mean that McIntyre’s criticism has merit at least in part?

    [Response: That's nuts. Do you think that anyone trusts a paleo-curve so much that a 0.4 sigma unit change on an individual year or decade has any consequence? Your definition of 'significant variation' is clearly at odds with mine. - gavin]

    >> and frankly I have a lot more confidence in Keith Briffa to do this right than I have in McIntyre

    That’s ad hominem – exactly what I didn’t want, it’s unhelpful

    >> I doubt very much that the issue raised have much merit. That reconstruction was the one that was made with that source material. With more source material (which is apparently being processed and added in) the chronology will change somewhat I suppose, but I’m happy to wait and see what comes out.

    So on the one hand you’re happy to wait and see, but on the other you’ve published a 1300 word blog entry stating that McIntyre is categorically wrong? Again I find that unhelpful.

    [Response: Perhaps you should read the top post again. I think it's pretty clear that the objection is to McInytre's unfounded implications that something underhand was going on. And yes, his rejection of 12 trees he doesn't like with no justification to create a new chronology (which we are now to understand wasn't meant to be a chronology at al) was wrong. - gavin]

    Looking forward to some clarity

    Mark

  18. 418
    Cumulus says:

    Dhogaza, you may or may not be right about the Financial Post fabricating that inflammatory blurb. Even if the Financial Post did, if McKitrick or McIntyre did not agree with that statement why have they not contacted the post to issue a correction? If they don’t, we can only conclude that they agree with the statement that:

    “Only by playing with data can scientists come up with the infamous ‘hockey stick’ graph of global warming”

    And that speaks volumes as to the real motive of their public “audits”.

  19. 419
    Tilo Reber says:

    dhogaza #401:
    “Tilo Reber, you know very well that climate science does not claim that temperatures will increase 0.2C every decade in monotonically increasing style, that natural variability is known about and acknowledged within climate science, and that all that’s stated is in terms of statistically valid, long-term trends.”

    Yes, I’m well aware that natural variability is able to mask the supposed effects of CO2. I have no problem with natural variability. And I have no problem with the idea of using a long enough time period so that most of the natural variability can be removed when drawing a trend line. But here is my issue. The period of time we are talking about is history. We have all of the data about it. We should be able to say that the current relatively flat trend is caused by ENSO or PDO or Volcanoes, or whatever. But we cannot identify an element of natural variability that is responsible for the flattening. For that reason the flattening becomes important, even though it is only 11 years.

    [Response: Can we move off this topic? some people might find the endless discussion of 10 or 11 or 9 years trends endlessly fascinating, but that would not include me. Pretty much everything that can be said has been said a dozen times. - gavin]

  20. 420
    Tilo Reber says:

    Gavin:
    [Response: If you look at the fossil trees you will see similar things, and of course there is a systematic issue related to sampling living trees that might well be younger on average than the fossil ones. Tom P. above showed that the Yamal curve was robust to homogenising the age structure, and frankly I have a lot more confidence in Keith Briffa to do this right than I have in McIntyre. - gavin]

    Actually, Gavin, Tom P’s data shows that the Briffa results are not robust. As Craig Loehle has posted, Larches seem to get more sensitive to temperature variation as they get older. Maybe that’s because their roots are deeper and they have less issues with water – who knows. But what we do know is this – the trees that Briffa has to represent the modern era are on average much older than the trees that Briffa has to represent older history. So when Tom begins to pull out trees, most of the trees that come out first are the trees in the older version. What we can see from his graphs is that the now older data begins to climb as compared to the contemporary data. Finally, when all of the younger trees have been removed from the older history we see Tom’s last chart. Now the trees from the earlier history are as old as the trees in the current era. The result shows that there is a peak around 800 that is larger than that around 2000. And there are peaks around 200 and 1450 that compete with 2000.

  21. 421
    dhogaza says:

    And that speaks volumes as to the real motive of their public “audits”.

    I’m extremely aware of their real motives. Just pointing out how things work in the press. I used to write an occasional column on natural history topics for my local daily and at times, the headline provided by the copywriter would make me cringe.

  22. 422
    Tom P says:

    Richard Sycamore,

    Thanks. I’d certainly be willing to put together a concatentation of my comments for RC and/or CA, although I’m waiting to see what Steve McIntyre’s promised response is first.

    I think there is some merit in taking on McIntyre’s criticism head on. I’m also rather impressed by the robustness of Briffa’s analysis having put some fairly stringent sensitivity tests on it.

  23. 423
    dhogaza says:

    We have all of the data about it. We should be able to say that the current relatively flat trend is caused by ENSO or PDO or Volcanoes, or whatever.

    You’re suggesting that climate scientists aren’t aware that 1998 was an El Niño year, or 2008 La Niña?

    Whatever, Tilo, whatever.

  24. 424
    Tom P says:

    Tilo Reber,

    Cross-posted from CA:

    You say:
    “What we can see from his graphs is that the now older data begins to climb as compared to the contemporary data.”

    No it doesn’t – the noise increases but the average remains the same at around an index of 1 until the 20th century – the hockeystick is maintained.

    http://img121.imageshack.us/img121/723/yamal72to200.gif

    If you look more carefully you can discern a slightly warmer period around 1100 (index of 1.2) and a cooler period from around 1500 to the 1800′s (index of 0.7). These would be the MWP and LIA.

    You said:
    “Finally, when all of the younger trees have been removed from the older history we see Tom’s last chart. Now the trees from the earlier history are as old as the trees in the current era. The result shows that there is a peak around 800 that is larger than that around 2000. And there are peaks around 200 and 1450 that compete with 2000.”

    The last chronology excluding all but the cores less than 250 years is statistically invalid. I posted it for completeness to show that the only way to break the hockeystick was to take out so many cores that the all we are seeing for most of the record is noise.

    I was concerned that there might be a few people with a weak grasp of statistics who might want to claim sudden very warm periods of a few decades scattered around the last two thousand years on the basis of this invalid chronology – at least you are not alone in making this error.

  25. 425
    Phil. Felton says:


    Cumulus says:
    4 October 2009 at 12:19 PM
    Dhogaza, you may or may not be right about the Financial Post fabricating that inflammatory blurb. Even if the Financial Post did, if McKitrick or McIntyre did not agree with that statement why have they not contacted the post to issue a correction? If they don’t, we can only conclude that they agree with the statement that:

    “Only by playing with data can scientists come up with the infamous ‘hockey stick’ graph of global warming”

    And that speaks volumes as to the real motive of their public “audits”.

    When challenged on this by Lorax I think McKitrick squirmed out of it by saying that he never had any input about the title and text immediately following. When I pointed out “And as an author when that title/comment does not accurately represent your comments don’t you have an ethical responsibility to write a clarifying comment to the publication? If they don’t publish it why would you ever write for them again?”
    McKitrick replied: “I don’t have a problem with the title. As far as I am concerned what this story is about it that a data set has been revealed to have a defect: the sample collapses just at the time the most prominent feature of the series emerges, a feature not shared in a comparable data set.” and “As for the NP article blurb, it is ambiguous because it refers to the “infamous ‘hockey stick’ graph”, which I take to refer to the MBH98 graph, and calling that episode “playing with data” is not inappropriate for what happened there.”

    So yes McKitrick does agree with the FP statement.

  26. 426
    Tilo Reber says:

    dhogaza:
    You’re suggesting that climate scientists aren’t aware that 1998 was an El Niño year, or 2008 La Niña?

    I’m saying that they are aware, but that it doesn’t explain the flat trend. And neither do any of the other natural elements of variation. Compensate for ENSO and you still get a near flat trend.

  27. 427
    Sean says:

    Hi there, I have what I think should be a straightforward & fundamental question about this topic, although as a layman I could be way off. I appreciate that the details of the algorithms used by Briffa and Mcintyre are beyond my scope so I won’t even touch it; so, I will leave those two to duke it out.
    However, I am wondering how the Siberian Yamal tree ring data can be used to extrapolate worldwide temperature. Perhaps these trees serve as decent proxies for determining local temperatures (given adequate treatment of the dataset). But, as I understand it this data has been used to generate [edit] global mean temperatures. In today’s world ‘Just because Antarctica is cooling doesn’t necessarily mean that the globe is as well’. If someone could reconcile these issues for me I would be grateful.

    [Response: Global mean temperatures are obviously the average of all the local temperatures. When you go back in time, the coverage of local temperatures gets worse than when compared to the modern instrumental record and so you have to assess how much weight to give the (fewer) records and over what time period that is valid. No single time-series for a specific location is simply assumed to be equivalent to global mean or hemispheric temperature, and that was never assumed for this Yamal record. Read Mann et al (2008) for an up-to-date summary of what is involved in these things. - gavin]

  28. 428
    Richard Sycamore says:

    Tom P,
    I think we should look very closely at what you’ve done. Perhaps it can be applied more generally to some of the other questionable analyses that have been perpetrated by that unsavory character. If he had any credibility he’d publish papers instead of launching half-cooked half-analyses from the confines of his comfortable echo chamber. What are his credentials, anyways?

  29. 429
    dhogaza says:

    What are his credentials, anyways?

    He has a BS in Mathematics, just like me.

    Which makes him as much an expert as I am.

    And no one mistakes me for an expert …

  30. 430
    Walter Manny says:

    Ray (405) If someone were knowingly to use a time series too short to be representative and to draw conclusions for a lay audience not sufficiently sophisticated enough to recognize the invalidity of the exercise, that would be dishonest, yes. Who dunnit? McIntyre, Briffa, Gore, Watt, Hansen? (In other words, I admit I have not had time to read this entire thread word for word.)

  31. 431
    Hank Roberts says:

    Beware trolling; google the name +climate and consider, before responding.

  32. 432
    Hank Roberts says:

    Hmmmm, Tom P, I see you responded already. Please think twice and check.

  33. 433

    Re;339
    “For AGW, I have the feeling, maybe untrue, that many outsiders are “believer” by default, but then when they start to scratch a little bit (because they have the basic math and physics skills to do so) they doubt more and more….”

    I’ve found the opposite to be true. If you take a zero dimensional model and equate the rate at which energy from the Sun is absorbed to the energy at which energy is radiated back to space, you obtain a value of Earth’s average temperature of about -18 C. The actual value of the Earth’s average temperature is about 15C.The reason for the difference is the natural greenhouse effect. Then it would seem to follow that adding more greenhouse gases would enhance that natural greenhouse effect.

  34. 434
    Jerry says:

    I live in a democracy, not in a technocracy. I am sorry about that, but that’s the fact jack. The snark and sarcasm that you folks use won’t win anyone over except for the converted.

    I’ve been using open source software for 20 years, and am a big believer in open sources, and transparency.

    I really would like to know why various data sets have been archived so poorly. Science is nothing if not repeatable, and I’ve never thought closed data said much about science.

    I think Steve McIntyre should be publishing, or presenting his publishing efforts and how they are denied or whatever his excuse is.

    But I just cannot take your site seriously, in large part because of the snark and sarcasm that is often used to bully people and seemingly shut them up.

    I just don’t recall any of my physics, or engineering, or chemistry, or biology professors acting that way towards the cranks that approached them, or telling us about how the great scientists would act that way.

    Once again, I live in a democracy, of the people, by the people, for the people. If talking to the people is frustrating to you, I can understand that, I can sympathize with you, I really couldn’t give a shit though, because the end result of your act is to encourage the people to treat all scientists and engineers and mathematicians and doctors etc., as the man behind the curtain.

  35. 435
    Hank Roberts says:

    Jerry, look people up before you believe the snark is sincere.

    The recent nastiness above is probably misrepresentation to try to make it appear someone concerned about climate change is writing that stuff. But look up the name of the poster +climate and consider the track record.

    You can’t assume anyone is nasty or evil — they may just be pretending to be a nasty person on the side they imagine is their enemy. People are weird.

  36. 436
    Cumulus says:

    Jerry if you think this is bad….go and see how they deal with dissenting views at CA. I come here often, and this is one of the very few times RC has adopted this tone. Can’t say I agree with it– perhaps they finally got fed up taking the high road and trying to engage McIntyre et al. on an intellectual level. Anyhow, be careful to extrapolate beyond this story.

  37. 437
    Hank Roberts says:

    Thankyou to

    Tom P (who) says: 3 October 2009 at 12:57 PM
    > Here are the chronologies perhaps a friendlier format

    Those links display fine in my (Mac/Intel/FF) browser, thank you very much.

  38. 438
    Ron Broberg says:

    re: 443 I live in a democracy, not in a technocracy. I am sorry about that, but that’s the fact jack. The snark and sarcasm that you folks use won’t win anyone over except for the converted.

    In one of my first physics classes, my professor posed a question and asked how many students supported one proposed solution. Then asked how many supported an alternative. Then he told us: “Let this be a lesson to you all. Science is not a democracy. And you are all wrong. If you care to know the answer, go look it up.”

    And that’s not only a fact, Jack. That there is an anecdote.

  39. 439
    Eli Rabett says:

    Jerry, a huge amount of the paleoclimate data is available on line. Noaa is one archive.

    What the noise here is about one series that until recently has been held as research material by a group which shared it with some others. You may be a huge believer in open access, but intellectual property is also important. The balance between them can be tricky, but jihads against the group that did not own the data for not sharing it are, well, very typical of Steve McIntyre.

    Hank: In drag as in wearing the clothes of others. No fun. We could have gotten through the thing a lot faster if we knew it was Steve (should have suspected tho). What is interesting is the huge number of wrongnesses that McIntyre through up. At the end only a few remained but that is all that anyone remembers. The same thing is happening with Briffa.

  40. 440
    Ron Taylor says:

    Jerry, the people who run this site are working scientists who volunteer their time to help people understand climate science. Yet, they all too frequently encounter posters here who are like the smart-assed freshman who struts into class and tells the professor he does not know what he is talking about. I am often amazed by the patience of the people at RC.

    Yes, we live in a democracy. But guess what? The outcome of global warming will not be determined by popular vote, but by the laws of physics. The people here know where we are headed based on those laws and they get understandably distressed with scientifically incompetent or dishonest efforts to discredit the science.

  41. 441
    Jim Eager says:

    Sorry, Jerry, science is not a democracy, and that’s a fact jack.

  42. 442
    Jonathan Baxter says:

    RE 433: “Then it would seem to follow that adding more greenhouse gases would enhance that natural greenhouse effect.”

    It does. By 1 degree for a doubling of CO2. No-one disputes that (well, some do, but not many). The dispute is over the feedback multiplier: you need 4X or more to justify the alarmist scenarios. The best the current state of climate science can do is put the multiplier somewhere between 0.5 and 5.0 (Lindzen has evidence for the smaller end of the range).

    [Response: And the ice age provides evidence for a number of around 2x (i.e. giving a 3 deg C/2xCO2) change. Who do you trust more - a geological processes that dominated climate for 2.5 million years, or Lindzen? ;) - gavin]

  43. 443
    stevenc says:

    Intellectual property is the property of the entity paying for the study. If Monsanto pays for it then it belongs to Monsanto, if Ford pays then it is Ford’s property, if the study is paid for with tax dollars then the intellectual rights belong to the tax payers. If you pay for the study yourself then you have absolute rights to the intellectual property.

  44. 444
    Eli Rabett says:

    Climate2003, as Hank said, has gone the way of all bad pages everywhere. fortunately we have the Wayback machine, and most of the links are there

    I give the link as a tinyurl, because the spam filter here clobbers USENET and web.archive links

    http://tinyurl.com/y9wynex

  45. 445
    Jack DeBeers says:

    Regular lurker, rare commenter.

    Sorry to interrupt the conversation but after reading the head post, it’s hard to believe that Steve McIntyre could pick any random set of tree rings from the internet and use them as temperature. Is anyone familiar with the data he chose or are they just unknown selections? And apparenlty he just writes his own software to make it all look good. Isn’t the original software good enough?

    Is this a scam or something, are these trees temperature sensitive, has anyone checked his numbers? Sorry if this has been covered somewhere else in this seriously long thread.

  46. 446
    Ron Broberg says:

    BTW, Jerry and SteveNC. I actually agree with ‘open sourcing the data and methods.’ It’s McIntyre&Co’s greatest contribution to the fields. But it’s a change from the way things used to be done. Like all change, some people and institutions resist more than others. But its change that is coming.

    Traditionally, peer review of results prior to publication was the standard by which reliability of analysis was determined. Careless or biased mistakes were supposed to be caught at that point. “Independent confirmation” wasn’t taking the original scientists’ raw data and running your own analysis, it was to develop an independent data sets (such as the satellite data sets) which helped to bolster or put in doubt the original published results. In essence, you were supposed to ‘repeat the experiment.’ Not just ask for the scientists’ data and ‘repeat the analysis.’

    But like I said, times change. More climate scientists, maybe even most, are becoming comfortable with idea of publishing raw data. Now there is more data and code for climatology available on the web than for any other science field that I am aware of. The number of places for deniers to hide behind their cries of Fraud! and Cheaters! is rapidly shrinking. The pitchfork and torches crowd is getting restless as their arguments continue to fall apart.

  47. 447
    Martin Vermeer says:

    Jerry (and others), nobody seems to recognize the tone of this post as an artfully crafted pastiche of McIntyre’s standard mode of discourse — the snark, the sarcasm, the routine assumption of bad faith, the lot. Yes, it grates. Yes it does ;-)

  48. 448

    Tilo Reber: maybe you’ve read about the paper by McLean, de Freitas and Carter alleging that ENSO accounts for all variability. That claim has been thoroughly debunked here and by Tamino.

    Do a bogus correlation of derivatives of the style of McLean et al. and you get a positive correlation between SOI and temperature. Correlate the actual data, and you get a negative correlation – all over the recent years you think are so important. Tilo, how about downloading the data sets and checking for yourself? Not too hard for someone so confidently sneering at professional scientists.

  49. 449
    Philippe Chantreau says:

    In 426, Tilo Reber says this: “Compensate for ENSO and you still get a near flat trend.”
    That is false. John Cook had a recent post on it at Skeptical Science.

    http://www.skepticalscience.com/Global-warming-and-the-El-Nino-Southern-Oscillation.html
    It refers Fawcett 2007 and Thompson 2008.

  50. 450
    Eli Snyder says:

    “The snark and sarcasm that you folks use won’t win anyone over except for the converted.”

    You sure? It works great for SNL, John Stewart et. al.

    There is a point of incredibility past which to engage a completely ludicrous argument in a serious and straightforward manner merely legitimates it. Most issues of political weight in our culture have long since passed that point. Beyond it, the only reasonable response is ridicule.

    The problem is that most people who are capable of following a serious debate on this technical a subject have already made up their minds. Anyone still on the fence must be there because they can’t follow the substance of the “debate” (put in quotes because a series of real, cogent arguments vs. a series of blatant falsehoods, misrepresentations and fallacies is not much of a debate).

    Therefore I think a little sarcasm is warranted, to remind people of how utterly silly the opposition arguments really are.


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