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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. 351
    caerbannog says:


    In light of recent studies of the influence of PDO on global temperatures…

    Are you referring to the study where the authors removed the long-term trend from their temperature time-series by differentiating it and then concluded that there was no long-term warming trend?

  2. 352
    chris says:

    Re # 305

    I don’t care about past ideological battles. I don’t care about the questioner’s motivation. It looks to me like an interesting and relevant question. It would be helpful to see an impartial response. Is there a website which makes a strong counter argument with facts and less passion?

    Try here:

    http://www.cru.uea.ac.uk/cru/people/briffa/yamal2000/

    or Tom P’s post #349 above…!

    I’m surprised you don’t care about the “questioner’s motivation”, natural feedback. That’s worthy of consideration I should think. In the case of the instigator of this particular storm in a teacup there does seem to be an extraordinary history of preemptive accusation of wrong-doing against scientists, that leads in essence precisely nowhere, while wasting a large amount of serious people’s time. The awesomely misguided “attack” on the so-called “hockey-stick”, for example, was shown to be scientifically without merit:

    Wahl ER, Ammann CM (2007) Robustness of the Mann, Bradley, Hughes reconstruction of Northern Hemisphere surface temperatures: Examination of criticisms based on the nature and processing of proxy climate evidence
    Climatic Change 85, 33-69

    http://www.metapress.com/content/h483676101066104/

    Ammann CM, Wahl ER (2007) The importance of the geophysical context in statistical evaluations of climate reconstruction procedures
    Climatic Change 85, 71-88

    http://www.metapress.com/content/c668835m747q4823/

    and McIntyre’s “critique” of Mann et al’s most recent paleoreconstruction:

    http://www.pnas.org/content/105/36/13252.abstract?ijkey=632a6e9c17f95c223f5ea8f18bb9c3f9dfe38df3&keytype2=tf_ipsecsha

    was simply pathetic (see links on same page)

    From a scientific point of view, we are interested in the entirety of the large body of paleoclimatology that informs our understanding of past climate and natural variation. That’s the value of Dr. Briffa’s work together with that of the multitude of other scientists who develop methodologies and analyses of this subject.

    Fundamentally, it’s all about the science. That’s how we find out about stuff of interest and value in the natural world. All the rest is self-serving rubbish, and it’s worth coming to a personal decision about what we think is important. When we’ve done that we might consider that the “questioner’s motivation” is actually of interest in how we use our valuable time…

  3. 353
    mike roddy says:

    This is only tangentally relevant, but as long as you’re talking about trees…

    Real Climate rarely addresses deforestation in detail, other than to give a nod to IPCC’s attribution of a 20% contribution to global emissions, and then maybe talking a bit about Brazil or Indonesia. Specifically, as with other sites, deforestation is not mentioned with respect to its impact in North America. This may be because the industrial forestry model, with replanting etc, is assumed to be less conducive to CO2 emissions than the kind of deforestation that occurs in the tropics.

    My own research indicates otherwise, and I have published an article on the subject that received no response from RC when I emailed it to you last year. The data came from post doc students in carbon forestry.

    This issue has enormous policy implications for the US and Canada. As Stern pointed out, avoided deforestation is a cheap and immediate way to reduce emissions- including right here in North America. It is also the one area of IPCC where the some of the data and language is not
    complete. This is because it was collected from academic foresters, many of whom are umbilically connected to the timber industry.

    Please look into this. I can refer you to the most highly regarded carbon forestry experts in the US, whose voices are often drowned out by industry. The media has also shied away from this issue, because they are big consumers of newsprint, which often comes from places such as the Canadian Boreal. Real Climate does not have this limitation, and this entire issue deserves a comprehensive look.

  4. 354
    Jonas N says:

    From # 321 ” Ideas and contributions have to evaluated on their merits, not from where they come from. – gavin”

    Ehh … did I really again miss the entire message of this post?

    [Response: Apparently you did. This post is about the overhyping of technical details into critiques and false assertions about scientist's integrity and the dramatic jumping to conclusions evident in the various responses. It is not, and never has been about the right of people to question or investigate the science themselves (despite what you might read elsewhere). - gavin]

    Isn’t the entire post, and many of the comments just an outcry over that Briffa and some more have been subjected to exactly what you claim to uphold so dearly?

    He Briffa (and some of you) have been reviewed by a peer. In this case somebody who points out the number of datapoints used for a certain chronology really aren’t that many, and that other data is available, and that the statistically significant conclusions that can be drawn from one tree (YAD061) really aren’t that robust.

    Why then the fuss? And why so much about the person, the press, and everything else completely irrelevant. If Steve M is wrong, then he is. Bad for him. But I don’t really se anybody questioning his assertions. But I see an aweful lot about completely other things.

  5. 355
    Tim S. says:

    I look forward to Keith Briffa (when he is feeling better, of course) writing a detailed article in which he explains his data selection process regarding the Yamal tree-ring controversy. I think that science benefits when questions are both raised and then answered. The politics of climate change (from both sides of this issue) all too often muddy the waters of understanding.

  6. 356
    Jeffrey Davis says:

    Ocean temps are the hottest ever recorded.

    If we want to talk about where the action is for Earth’s temperature: ocean temps are the hottest ever recorded.

    (Why are we still debating this? The word on this came out, I believe, over a month ago. Don’t climate septics read?)

  7. 357
    Hank Roberts says:

    Tom P, or anyone, ImageShack says the Mac (OSX, Intel) needs a plugin but there isn’t one to see the images there. Any pointer welcome.

  8. 358
    Hank Roberts says:

    Mike Roddy, can’t get your link to work; pointer?

  9. 359
    Rod B says:

    Is Bill Maher the new climate science poster child??

  10. 360
    jd says:

    I can help wondering about tree ring data from Yamal which is tree-less tundra. What about tree ring data from Antarctica or the Sahara desert or the middle of the ocean?

    At least bristlecone pines are actual long-living trees.

    This whole thing looks like a stunt.

  11. 361
    Ray Ladbury says:

    Greg Kai,
    Don’t look for the “definitie” reconstruction–a new one will take its place in a year or so. Rather, ask yourself what all the reconstructions in aggregate are talling you–e.g. it’s warmer now than in the past 2000 years! That is how science works. Don’t focus on one data series in one paper for over a decade. That is not science. This is what the McAuditors are missing (well, that and about 30 IQ points).

  12. 362
    Ray Ladbury says:

    Tim S. says, “I look forward to Keith Briffa (when he is feeling better, of course) writing a detailed article in which he explains his data selection process regarding the Yamal tree-ring controversy. I think that science benefits when questions are both raised and then answered. The politics of climate change (from both sides of this issue) all too often muddy the waters of understanding.”

    Fine from a history of science, perspective–but it ain’t science. Science will have moved on by then to new understanding.

  13. 363
  14. 364
    Solomon Green says:

    I do not understand dendrology. However before I bacame a statistician, I was for several years involved in growing trees professionally. Growth depends on many things, light, moisture (both atmospheric and ground, temperature, nutrients, age and parasites are some that spring immediately to mind.

    As a statistician I believe that it is necessary to eliminate the effect of all other variables before one can be sure that there is a genuine correlation between any two. It is not even sufficient to hold all but two of the variables stationary while examining the correlation between the remainder, since until proved otherwise they are all interdependent.

    Tree rings are useful for determining age but to draw any firm conclusions as to temperature or other short term atmospheric conditions from ancient tree rings is to put faith before math.

  15. 365
    Ray Ladbury says:

    Chris says, “However, since then the average anomaly has been +0.41C (Jan 2008 to Aug 2009), which is comparable to 13 years ago (+0.42C for Jan 1995 to Aug 1996).”

    Please, tell me you are joking! You guys are down to comparing averages over 18 months! Thanks, next time I want to know whether to wear a jacket, I’ll tune into what you have to say–or the Weather Channel. They’re equally relevant to climate science.

  16. 366
    Steve Fish says:

    Hey jd (~360, 12:30PM):

    Because I share your concern about stunts offered up in serious communication (what this topic is about), I recommend that you re-post some serious and respectful questions so that you might actually get a substantive answer.

    Steve

  17. 367
    Tilo Reber says:

    dhogaza:
    “I also stated that the fact that changing the starting point by one year causes the slope to switch from negative to positive tells us something about using ten-year time periods,”

    Not really. The switch is from a very small negative to a very small positive. In both cases the .2C per decade temperature increase that you would expect from the CO2 increase is missing.

    Also, Gavin and Hansen have published papers that only included 10 years of data and they drew strong conclusions based upon that 10 years.

    [Response: I did? Hmmm... Perhaps you could remind me of where I drew a 'strong conclusion' based on linear trends that weren't even close to significant? or where Jim did either? - gavin]

    The problem with the flattening of the temperature trend, whether it be slightly positive or slightly negative is not its length, but rather that it is not explained by any known elements of natural variation. The only element of natural variation that seems to point to a solution is the Svensmark cosmic radiation theory.

  18. 368
    David B. Benson says:

    Tkearney (331) — Roger Bacon was an early European advocate of empiricism:
    http://en.wikipedia.org/wiki/Roger_Bacon
    but the scientific method didn’t thoroughly take hold until Francis Bacon:
    http://en.wikipedia.org/wiki/Francis_Bacon#The_New_Instrument
    I don’t give him sole credit.

  19. 369
    Jim Galasyn says:

    One of the “young dendros” speaks!

    Unlike many of the people posting here, I have actually cored trees and studied the rings. … I have to say, McIntyre sounds reasonable when he questions the wisdom of attaching significance to such a truncated data set, and I wonder how the work of Briffa obtained such prominence

    Great, so you’ll be publishing your critique in the peer-reviewed literature soon, yes?

  20. 370
    Hank Roberts says:

    Solomon Green says:
    > I do not understand dendrology

    Yes you do, you were doing it, before you became a statistician.
    http://www.google.com/search?q=define%3Adendrology

    Dendrochronology is what you don’t understand.

  21. 371
    mike roddy says:

    Hank Roberts, #358:

    The link is
    http://forestcouncil.org/pdf/CO2emissions-Roddy.pdf

    You and others would probably be more interested in the background research, detailing the methodology. I don’t have a link, but will send it to you on request if you email me at greenframe@aol.com.

    I’ve been at this a long time, and have been before Congressional committees on timber industry subsidies. As you probably know, there are a lot of problems with our timber consumption in addition to CO2.

  22. 372
    Steve Fish says:

    Solomon Green (~364, 1:00PM):

    I know very little about this area of science although I generally trust the scientists, especially when they have a body of work on a subject. Because of your strong assertion regarding tree rings being valid for age but not for any other variable, could you please explain your analysis of Briffa’s methods in his research articles on the subject?

    Steve

  23. 373
    Tilo Reber says:

    Gavin:
    [Response: I did? Hmmm... Perhaps you could remind me of where I drew a 'strong conclusion' based on linear trends that weren't even close to significant? or where Jim did either? - gavin]

    No problem:

    http://www.sciencemag.org/cgi/content/abstract/1110252

    From abstract:
    “This imbalance is confirmed by precise measurements of increasing ocean heat content over the past 10 years. Implications include (i) the expectation of additional global warming of about 0.6°C without further change of atmospheric composition; ”

    [Response: Those trends in that OHC data set are very significant indeed. And they remain significant in recent updates to the OHC numbers by Levitus and others. The issue is not the period of time, but the ratio of signal to noise. 10 years is not enough for the global tempertures, it can be enough in other metrics. - gavin]

  24. 374
    Cumulus says:

    For those of you are not aware, Ross McKitrick published an intriguing diatribe in the Canadian newspaper the National Post on Friday, 2 October, that ran under the title:

    “Ross McKitrick: Defects in key climate data are uncovered

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

    By Ross McKitrick”

    Read the entire missive at:

    http://network.nationalpost.com/np/blogs/fpcomment/archive/2009/10/01/ross-mckitrick-defects-in-key-climate-data-are-uncovered.aspx

    or using this link: http://tinyurl.com/yg4d7pu

    Aside from the clearly libelous title, you will notice that McKitrick’s missive contains misinformation, bias and distortion. The angle is clearly to try and paint the whole AGW theory as a big lie which is built on a house of cards.

    McKitrick assures readers at ClimateAudit.org that he was not informed by the newspaper that they were going to run with “Only by playing with data can scientists come up with the infamous ‘hockey stick’ graph of global warming”.

    McKitrick has stated at ClimateAudit.org that he is not interested in asking the paper to issue a correction, and has been quite dismissive and cavalier about the whole sad affair.

    Anyhow, I urge all those concerned to contact the National Post and request them to (at the very least) issue a correction, those expressing their concerns should also point out the misinformation and misleading parts included in McKitrick’s missive. Really, this is the kind of thing I would have expected from Lord Monckton.

    I urge readers who are offended/concerned by this piece to please express your (polite and quantitative) concerns to all of the following people at the National Post:

    Tcorcoran@nationalpost.com
    kmcparland@nationalpost.com
    jturley-ewart@nationalpost.com

    Somebody should probably also notify Briffa.

  25. 375

    Jim Cross:

    In light of recent studies of the influence of PDO on global temperatures and the suggestions that there may be factors that magnify the solar irradiance influence, fifty or sixty years (or perhaps 100) might be more useful.

    Variance accounted for in NASA GISS temperature anomalies, 1900-2007:

    Solar cosntant: 2.5%

    PDO index: 4.0%

    Ln CO2: 75%

    Exercise for the student: Can you arrange these numbers in descending order by magnitude? Which process is having the largest effect? The smallest?

  26. 376

    Tilo Reber:

    The only element of natural variation that seems to point to a solution is the Svensmark cosmic radiation theory.

    What part of “cosmic ray flux has shown no trend for 50 years while temperatures have increased sharply” do you not understand?

  27. 377
    luminous beauty says:

    Solomon Green,

    As a statistician I believe that it is necessary to eliminate the effect of all other variables before one can be sure that there is a genuine correlation between any two. It is not even sufficient to hold all but two of the variables stationary while examining the correlation between the remainder, since until proved otherwise they are all interdependent.

    Perhaps while growing trees professionally you heard of something called Leibig’s Law of the Minimum? This is primarily why climate sensitive dendro specimens are carefully chosen according to strongly limiting criteria rather than randomly selected from general population stands of a given species. Furthermore, information beyond mere ring width such as cell size and number, chemical composition and atomic isotope analysis are used to remove confounding effects. A simple explanation is provided here:

    http://www.youtube.com/watch?v=vqicp4PvHrY

    If you want to learn more, good introductory textbooks are:

    http://www.amazon.com/Tree-Rings-Climate-H-Fritts/dp/1930665393/ref=ntt_at_ep_dpi_1

    And:

    http://www.amazon.com/Tree-Rings-Basics-Applications-Dendrochronology/dp/9027724458/ref=pd_sim_b_3

    For more up-to-date graduate level study, there’s:

    http://www.amazon.com/Tree-Ring-Analysis-Biological-Methodological-Environmental/dp/0851993125/ref=pd_sim_b_2

    And:

    http://www.amazon.com/Methods-Dendrochronology-Applications-Environmental-Sciences/dp/0792305868/ref=pd_sim_b_2

  28. 378
    Phil. Felton says:


    Tkearney says:
    3 October 2009 at 7:04 AM
    For an deconstruction of McIntyre’s analysis and McKitrick’s Da Vinci Code-style claims, read something from actual working climate scientists
    ….

    Um, Einstein was not an ‘actual working’ physicist

    He certainly was, his office was within half a mile of where I’m typing this! That he was working as a technical assistant in the Swiss Patent Office while completing work on his PhD in order to support his family because he hadn’t been able to get a teaching position is irrelevant.

  29. 379
    Steve Bloom says:

    Re #353: Mike, I don’t think it’s so much a lack of interest as a consequence of where the expertise of the RC authors is focused (not in the biological sciences), and of the fact that ten times as many posts still wouldn’t be keeping up with the breadth of the science. That said, there was a recent forestry-related RC guest post by Jim Bouldin, who I believe does have the expertise to address the issue you raise, so getting in touch with him seems like the thing to do.

  30. 380
    Cumulus says:

    Someone by the name “The Lorax” has been trying to ask some questions at ClimateAudit.org about the Briffa case and the perils of conducting audits in the public forum. It has been interesting, no depressing, to watch. CA closed ranks and bombarded Lorax with vitriol, ad hom attacks and childish remarks. To say that they rallied to McIntyre’s and McKitricks defense (no questions asked) would be a gross understatement. They even chided Lorax by offering to “baby sit him/her” and telling him/her to “read THE BLOG” (“The Blog” being the entire CA site, which apparently is of biblical importance).
    Other than the poor Lorax, it has been crickets at CA, everyone high-fiving everyone else, and continuing to make allegations against Briffa.
    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? There are more official and appropriate means for doing audits. Lorax tried to tell CA that but they just got more aggressive and condescending.

    I think that this needs to be said. Briffa erred by delaying, he also made some perplexing choices of which tree rings to include or which not to include. He did have options, he could have said “I will have my data audited, but it will be done in private by an unbiased and independent third party. The findings of that audit will only be released upon its conclusion.” The tree-ring matter needs to be resolved, but to draw that work into the public forum as has been done by McIntyre, McKitrick and Piekle Jnr. before it has been resolved is absolutely nuts.

    Also, what we need to do to mitigate the imnpacts of AGW is independent of the tree ring proxies. There are several other temperature reconstructions (which do not use tree rings) which we can use to place the warming of the 20th and 21st century in context. Question the tree rings all you want, fair enough let us do the analyses properly and be transparent, but at the end of the day those tree ring analyses are not a make or break for the theory of AGW as McKitrick is implying.

    Why are people who are posting here, not there (at CA) asking some difficult questions about McKitrick’s paper, how McIntyre ties in with McKitrick’s paper, the contents of McKitrick’s paper?
    There are obviously some CA trolls here trying to be disruptive. Don’t go to CA to be disruptive but to try and start some dialogue, to present a n alternative view and to debate the science.

  31. 381
    Hank Roberts says:

    http://www.agu.org/pubs/crossref/2009/2009GL040142.shtml

    “… increase in solar-cycle averaged TSI from the Maunder Minimum to the present amounts to (0.9 ± 0.4) Wm−2. In combination with climate models, our reconstruction offers the possibility to test the claimed links between climate and TSI forcing.”

    Citation: Steinhilber, F., J. Beer, and C. Fröhlich (2009), Total solar irradiance during the Holocene, Geophys. Res. Lett., 36, L19704, doi:10.1029/2009GL040142.

  32. 382
    Hank Roberts says:

    Simon Green wrote:

    > As a statistician I believe that it is necessary to eliminate the
    > effect of all other variables before one can be sure that there is
    > a genuine correlation between any two.

    Are you referring to something like this?

    Estimating the strength of genuine and random correlations in non-stationary multivariate time series
    M. Müller, G. Baier, C. Rummel and K. Schindler 2008 EPL 84 10009 (6pp) doi: 10.1209/0295-5075/84/10009
    http://dx.doi.org/10.1209/0295-5075/84/10009

  33. 383

    #365 Ray, correct reasoning would dictate a reflection of Temperature Vs CO2, as a mirror, in the short term, not driven by astronomical cycles as the lags of distant past, but a CO2 forced reverse lag tempered by winters. World wide sst’s are the warmest ever, along with GT’s as high as recorded, even with a much weaker El-Nino than 1997, 2.5 times weaker, we are warmer . it is astounding to read someone claiming flat temperatures.
    I cant explain why some do not study climate in a comprehensive way, coming with incoherent conclusions.
    Reading the numbers with an agenda perhaps warps intellectual processing? If those who claim temperatures as being flat care to reason, a little bit more, then why are they? As they claim……. flat? If CO2 doesn’t have any radiative powers, why are the temperatures so high? Should the temperature anomalies vary up and down the 0 degree mark? Despite variances driven by ENSO?

  34. 384
    Marion Delgado says:

    It’s a worse-than-unserious question/objection in this case to talk about hiding data. The data was not Briffa’s but the Russians’. Assuming PaulC above is sincere and not trolling, all the people that bring that up to him are either abysmally ignorant or completely dishonest. They don’t really merit a response in the latter case, and I wish him luck in the former case.

  35. 385
    Tom P says:

    Cumulus,

    Read what I have written on the Climate Audit here:

    http://www.climateaudit.org/?p=7241

    as well as posted above. Briffa’s CRU archive is extremely robust to an age-sensitive test. There is no reason from the statistics to think that there has been any conscious or inadvertent bias in constructing the Yamal chronology.

    Steve McIntyre’s critique was rather uncooked (to be kind) but he appeared to be in quite a rush to find fault and has left behind a bit of a mess.

  36. 386
    Eli Rabett says:

    Jim Cross is wrong in #344. Data, like it or not is intellectual property and if someone has shared data with you, you cannot give it to a third party without their permission. More bluntly put if anyone tried it no one would ever share data with them again because no one would trust them. This is a well established ethical constraint

    It appears that what we have here is McIntyre berating the wrong party. Without wading through the morass, did McIntyre ever ask the Russians for the cores or the associated data??

  37. 387
    mike roddy says:

    Thanks, Steve Bloom, for the reference to Bouldin’s post. The problem is that he says nothing about human impacts at ground level, which is of course mostly industrial logging. Reducing these practices is where we could really make some headway.

    I suggest that you ask Dr. Hansen of UC Davis to make the next post on the subject.

  38. 388
    MarkB says:

    Solomon Green (#364),

    You stated:

    “Tree rings are useful for determining age but to draw any firm conclusions as to temperature or other short term atmospheric conditions from ancient tree rings is to put faith before math.”

    after stating:

    “I do not understand dendrology.”

    Perhaps you should work to understand dendrology by reading the variety of studies in the literature. Else, you’re strong conclusion about its usefulness is putting faith before facts.

  39. 389
    CTG says:

    Isn’t it about time there was a ClimateAuditAudit site, where the work of McIntyre could be subject to independent scrutiny?

    After all, by removing 12 cores and substituting 34 different cores, isn’t McIntyre guilty of precisely the offence that he (didn’t) accuse Briffa of? Who is holding McIntyre accountable?

  40. 390
    Hank Roberts says:

    Mike, follow the link to Jim Bouldin’s website; what you see here is the climatology aspect but his website will have much more of interest to you.
    He’s taught me a lot just as an amateur reader and wildland restoration geek.

  41. 391
    Walter Manny says:

    Ray (334), thanks for the follow-up, though I’m not sure why you brought up the 1998 cherry-pick. I didn’t. Once again, though, to try to stimulate your curiosity about post-1999 data, I would refer you to:

    http://www.woodfortrees.org/plot/hadcrut3vgl/last:111/mean:12/plot/hadcrut3vgl/last:111/trend

    Absolutely, I picked data in and around sample size 111 to find the flat linear trend, and while there is nothing special about the “double-Nelson” 111, there is surely nothing special about 120 either, is there? With the UAH data, I can find the flat trend line at 115:

    http://www.woodfortrees.org/plot/uah/last:115/mean:12/plot/uah/last:115/trend

    Yes, farting around with these graphs proves nothing, but I am intrigued by the lack of curiosity exhibited by so many posters here about other than “hot” interpretations of recent temperature trends. Isn’t it trying to have it both ways to critique decadal temperature flatness as mere “weather” and in the next breath talk up the record-breaking 2009?

    In any event, it’s back to the Ministry of Silly Graphs with me (Cleese and Palin still live!)

  42. 392
    Deep Climate says:

    Decadal doesn’t mean “over the course of a decade”. It means from one decade to the next. So there is no “decadal flatness”. So far there has been global warming in every decade since the 1970s.

    I discussed this misunderstanding in these recent posts:

    http://deepclimate.org/2009/09/25/nyts-andy-revkin-backtracks-but-not-nearly-enough/

  43. 393
    Ray Ladbury says:

    Walter Manhy, If you want to play areound with short time series, that is your business–not particular illuminating in my opinion. Where I object is when you and others contend that 10 years worth of data invalidates 30 years worth, or 130 years worth. The only way you can get “cooling trend” is by fooling around until you find the right starting and endpoints. To contend that that has any meaning at all is dishonest.

    On the other hand, to say that ocean temperatures are higher than they’ve ever been in the instrumental period or to call attention to record low ice extent in 2007 is perfectly valid when those facts are viewed as part of a long-term trend toward higher temperatures or shrinking icecaps. At this point, to contend that the planet is not warming well beyond anything experienced in human civilization requires one to ignore a mountain of facts.

    In contrast, denialists must distort the data to the point where it is utterly unrecognizable before they have anything that supports their sanguinity. Silly is only one adjective that applies.

  44. 394
    Ray Ladbury says:

    Cumulus, Now hold on just a wee minute. One does not release data one has obtained elsewhere without the express consent of the individual one got it from AND from whoever signs the paycheck of said individual. There is nothing to stop McI or any other Frauditor from going to the Russians and asking for the data. There is no reason why, given McI’s lack of publication record, the Russians should take him seriously, but if they did, McI could then audit the data to his hearts content. Ignoramuses who know nothing of how science is done have no business criticizing Briffa or other working scientists. NONE! Science doesn’t advance by “audits”. It advances when other researchers improve on a previous result and in so doing either confirm or refute it.

    To date, ALL reconstructions show a hockey-stick like rise in the 20th century. Some hockey sticks have long handles, some shorter, but the anomalously large rise in temperature in the 20th century AND EXTENDING INTO THE 21ST, is undeniable. Briffa’s work is thereby confirmed.

  45. 395
    CTG says:

    Re #391 W Manny

    You are right that there is nothing special about 111 or 120 months as a sample size. Why? Because at that length of time, most of the variance in the graph is coming from internal variability (i.e. weather), not the long-term trend.

    The minimum trend length that has any statistical significance (in the global temp record, not as a general rule) is 21 years, as discussed here: http://moregrumbinescience.blogspot.com/2009/01/results-on-deciding-trends.html.

    That would be 252 months, which would make the graph look like this: http://www.woodfortrees.org/plot/hadcrut3vgl/last:252/mean:12/plot/hadcrut3vgl/last:252/trend

    Flat, much?

  46. 396
    Russell Seitz says:

    Barton Levenson asks:

    “Al Gore was one of Roger Revelle’s students in the 1960s, which means he’s taken at least one more climatology course than George Will has. Do you know who Revelle was? Do you know what he did?

    Roger’s achievements as an IGY organizer and godfather of CO2 monitoring should not be confused with his very popular survey of environmental science for humanities students .

    As a subsequent record of peer reviewed primary publications even shorter than than McIntyre’s indicates, the keystone of Al’s Sixties science education was a gut course as celebrated as Physics for Poets and Rocks for Jocks,

    So sophomoric an introduction to climatology could only benefit complete tyros like, well, Steve McIntyre and the Climate Audit audience, so I suggest we club together to buy Steve a copy of the course materials , or better still, a Gore Vice Presidential Library card, so he can check out the originals, and benefit from the marginal notes by Al’s long suffering and never ending stream of science tutors.

    As to Gavin’s objection that ;

    “This post is about the overhyping of technical details into critiques and false assertions about scientist’s integrity and the dramatic jumping to conclusions ”

    Is the debate over, or are we waiting for the station to stop at the next death train?
    In the run up to Copenhagen, hyperbole is contagious as swine flu, and instead of investing in a vaccine, both sides seem to be doubling down on their advertising budgets.

  47. 397
    Walter Manny says:

    Ray: “To contend that that has any meaning at all is dishonest.” Here is where you and yours get yourselves in the soup, repeatly. To conflate disagreement and dishonesty, to me, is a dull rhetorical axe. I don’t believe all this animus advances the ball one way or the other, but that said, I do appreciate your observations on the subject, as always.

  48. 398
    Mike says:

    Ray Ladbury says:
    “At this point, to contend that the planet is not warming well beyond anything experienced in human civilization requires one to ignore a mountain of facts.”

    I understood the Holocene thermal maximum was warmer than the current climate? As shown by the vostok/greenland ice core climate reconstructions. So it “may be the warmest its been in the last couple o centuries(i wouldnt debate that) And possibly for the last couple o millennium(it was declining from the maximum) but the warmest during human civilization may be a bit o a stretch.

    I dont believe what is being implied by the tree ring reconstruction critique is that the current instrumental trend is flawed, more so that the possibility of the historical oscillations may be understated?

    [Response: Actually it's not clear if the early Holocene was warmer globally. It certainly was in northern hemisphere summers (as a function of orbital precession - closest approach to the sun was in August instead of January at present times), but there was less tropical insolation and evidence of cooler tropics at that point. However, whether it was or not, it was driven to a large extent by the slowly changing orbit - not something that is relevant over the last 50 years. - gavin]

  49. 399
    Hank Roberts says:

    Walter, you’re claiming that the math used in statistics — how to determine how many samples are needed to assess a trend — is a matter of opinion over which reasonable people can disagree.

    Reasonably innumerate people may well disagree with the math.

    But you know it’s dishonest to claim as meaningful a span that’s insufficient to be meaningful mathematically for the statistical test being done.

    If it doesn’t add up, that’s not a matter of honest disagreement, except among people who can’t count that high.

  50. 400
    dhogaza says:

    McKitrick assures readers at ClimateAudit.org that he was not informed by the newspaper that they were going to run with “Only by playing with data can scientists come up with the infamous ‘hockey stick’ graph of global warming”.

    This actually would appear to be one of the rare cases where McKitrick is telling the truth. Copyeditors, at traditional newspapers (and I’m sure their online editions), not columnists or journalists, write headlines, and news articles may appear with different headlines in different editions (back when newspapers had multiple editions per day, at least!).

    McKitrick has stated at ClimateAudit.org that he is not interested in asking the paper to issue a correction, and has been quite dismissive and cavalier about the whole sad affair.

    Of course. His article is every bit as bad as the headline. After all, he ends the article by saying “this [briffa's research] is not science”.


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