the Air Vent

Because the world needs another opinion

The Return of Yamal

Posted by Jeff Id on December 2, 2009

Something I was unaware of was the cooperation between Briffa and the collectors of the Yamal data and paper.  Keith Briffa has an odd writing style where he’ll flat contradict his own paper and still come to the same conclusions.  In this case I’ve long wondered about Hantemirov’s paper on Yamal and one particular statement in it.   Keith Briffa Hokeysticizated Yamal after this graph was produced and his version is the one always used.  In this case the unhockeysticizated version is discussed before publication.  Oddly Briffa refused coauthorship.

From: Rashit Hantemirov <rashit@ipae.uran.ru>
To: Keith Briffa <k.briffa@uea.ac.uk>
Subject: Re: Yamal paper for The Holocene special issue
Date: Wed, 21 Aug 2002 17:56:18 +0500
Reply-to: Rashit Hantemirov <rashit@ipae.uran.ru>

Dear Keith,
thank you very much for editing our paper. It’s a pity you strike your name off the list of authors, you
make an important contribution to writing paper. Your corrections and additions surely improve paper.

I would only notice the next sentence (page 8):

‘The low interannual variability and the minimum occurrence of cold extremes during the 20th century, argue that the most recent
decades of this long summer record represent the most favourable climate conditions for tree growth within the last four
millennia.’

I’m not sure that this statement follows unambiguous from results presented in this paper. Because mean temperatures during last
decades, according presented reconstruction, are not exceptional. Besides, e.g. period about 1700 BC, according this
reconstruction, represent probably the same conditions taking into account low variability, low occurrence of extremes and high
mean temperature.
May be to soften this statement and replace ‘the most favourable’ with something like ‘highly favourably’ or ‘probably the most
favourable’?

Thank you once more for invaluable assistance.

Best regards,
Rashit M. Hantemirov

(I’m sorry for the late answer, I just come back from the trip to
the north.)

Lab. of Dendrochronology
Institute of Plant and Animal Ecology
8 Marta St., 202
Ekaterinburg, 620144, Russia
e-mail: rashit@ipae.uran.ru
http://ipae.uran.ru/8personalies/dendro.html#3

I’ve bolded the important bit’s.  The most favorable comment was written by Keith Briffa after seeing this data:

The most favorable ‘fastest growing’ section according to Brifa is the bit in the bottom right corner. Now in the paper Holocene_v12a[1] the final version from what I gather read like this:

Recent warming is also clear, especially if it is judged to have
commenced at the beginning of the nineteenth century. The low
interannual variability and the minimum occurrence of cold
extremes during the twentieth century argue that the most recent
decades of this long summer record represent one of the most
favourable climate conditions for tree growth within the last
four millennia.

I’ve always wondered how that fit the interpretation of the incredibly flat curve above.  In one of these emails I learned that Hantemirov was a young guy trying to work in this field.  Briffa collaborated with them to get a lot of data from the Yamal region.  I think this last paragraph in the papers discussion (link above) is pretty telling about the poor quality of temperature records from tree ring data.

The more northerly tree-line suggests that the most favourable conditions
during the last two millennia apparently occurred at around ad
500 and during the period 1200–1300. It is interesting to note that
the current position of the tree-line in Yamal is south of the position
it has attained during most of the last three and a half millennia,
and it may well be that it has not yet shifted fully in response
to the warming of the last century.

So from that version of Yamal using corridor standardization Briffa has used a different method on the same data and his reconstruction looks like this:

https://noconsensus.files.wordpress.com/2009/10/yamal-with-dozen-overlay-zoom1.jpg

Briffa Yamal using same data as Figure 1 - Black line is his version.

20 Responses to “The Return of Yamal”

  1. dearieme said

    “the most favourable conditions during the last two millennia apparently occurred at around ad 500 and during the period 1200–1300.”
    So the upswing to hot weather must have coincided with the Romans coming from Italy to Britain, and the Normans coming from France. Now Britain has lots of immigrants from Bangladesh and Somalia – which are even hotter than Italy and France – so that must mean we are on another upswing to a record hot spell, mustn’t it?

  2. stan said

    Did Briffa use Mannian statistical techniques to derive his graph from the same data that produced the fourth part of the graph above? Or does he have his own tricks?

  3. Jeff,
    Really nice!
    TL

  4. Chris S said

    How common is it for papers to be “ghost written” or amended by Scientist who are then not named as co authors or contributors?
    I had previously read this e-mail and it seemed innocuous until you placed it in context.

    Many papers may need to be looked at again in the light of the leaked e-mails.

  5. Mike S said

    “I’ve always wondered how that fit the interpretation of the incredibly flat curve above.”

    Actually, that bit makes sense. The last few data points have an overall range (max-to-min) of less than 2 degrees, and the temperature anomalies dip only slightly below zero. Hence, “low
    interannual variability and the minimum occurrence of cold extremes”.

    They definitely needed the “one of the…”, though, for their statement to work. From the graph, the period around -530 looks nearly as good, and around -585 looks better. Around -1700 would have them all beat if not for what looks like just one much colder year. Don’t see any legitimate way to make the claim that the last little bit was “the most favourable climate conditions for tree growth within the last four millenia.”

  6. John F. Pittman said

    JeffID, it is even more interesting when you read what was written in 1997 that I started my post “Context” out with the following quote:

    From: Eugene Vaganov evag@xxxxxxxxx.xxx

    To: k.briffa@xxxxxxxxx.xxx

    Subject: from Vaganov

    Date: Thu, 6 Mar 97 14:40:15 +0000 (KRS)

    The specific objectives of this proposal are the development of two supra-long (each spanning 6-9000 years up to present) continuous larch ring-width chronologies at two distant each other high-latitude locations of Siberia (Yamal and Taimyr peninsulas). Ring-width chronologies developed from coniferous trees growing at the polar timberline in Siberia contain a very strong climatic signal, mainly summer air temperatures. With these chronologies high-resolution continuous and quantitative reconstruction of summer temperatures will be made.

    3.2 OBJECTIVES This research will make a major contribution to our knoweledge of high-resolution climate variability at high latitudes of Western and Middle Siberia throughout the Holocene using the unique potential of tree-ring data. The specific objectives of this proposal are as follows:

    – to develop two supra-long (each spanning 6-9000 years up to present) continuous ring-width larch chronologies at two high-latitude locations of Siberia; – using these tree-ring chronologies, to make a multi-millennial high-resolution continuous and quantitative reconstruction of summer temperatures;

    – to analyse spatio-temporal patterns of temperature variability at these locations over a range of timescales (annual, decadal, multi-decadal and centennial) and their connections with various forcing factors and other annual resolution records being developed elsewhere in the Arctic and Subarctic.

    3.3. BACKGROUND Reconstruction and analysis of natural climatic changes through the whole Holocene at high latitudes are of great importance as climatic conditions, especially air temperature, are most variable and sensitive to various forcing functions (Budyko, 1980; Jones and Kelly, 1983; Intergovernmental Panel on Climate Change, 1990). However, there are a minute quantity of long, precisely-dated and high-resolution proxy climatic series for these regions.

    Tree rings as a proxy indicator of the past climatic conditions are of special interest as they allow to reconstruct climatic parameters with seasonal and annual resolution for many hundred and thousand years, to provide an exact absolute and relative dating of the tree-ring data, to establish high-frequency climate changes (from interannual to centennial timescales) with high confidence, to obtain dendroclimatic information practically for every site where trees grow at present or grew in the past.

    Ring-width chronologies developed from coniferous trees growing at the polar timberline in moderate-continental and continental regions of Siberia contain a very strong climatic signal, mainly summer air temperatures of tree growth year (Graybill and Shiyatov, 1992; Briffa, Jones, Schweingruber, Shiyatov and Cook, 1995; Hantemirov, 1995; Vaganov, Shiyatov and Mazepa, 1996). The explained variance over the calibration and verification periods is highest reported in the literature to date (65-70%) and it allows to make a quantitative reconstructions of summer temperatures. These chronologies and temperature reconstructions will be the first to be so long, reliable, annually-resolved and precisely-dated with known reliability across the whole of northern Hemisphere. These reconstructions will allow to compare and contrast the details of temperature changes at the moderate-continental region of Yamal Peninsula with the continental region of Taimyr Peninsula and allow modern and predicted temperature patterns to be compared with variability patterns of pre-industrial era.

    – The Climatic Research Unit of the University of East Anglia, Norwich, Great Britain is one of the world’s leading research organisation specialising in the study of climate change: climate history, current climates, projected changes and impacts. Dr. K.R.Briffa, Senior Research Associate at the Climatic Research Unit, has considerable experience in climatology and with the use of statistical methods of climate analyses and dendroclimatic reconstruction, especially with regard to large-spatial-scale reconstructions of climate patterns and published many articles on the theoretical and practical aspects of dendrochronology and dendroclimatology, and on use of paleoclimate data for understanding current and possible future climates.

    Dr K.R.Briffa (Climatic Research Unit) will be the responsible scientist on the proposed project and he will take part in analysing growth-climate relationships, developing statistical models of tree growth, extracting climatic signal, reconstructing and analysing climatic conditions of the remote past.

    The Russian laboratories together with the Climatic Research Unit of the University of East Anglia during 1997-1999 will be analysing the material obtained (standardization of individual series, development of mean chronologies, studying growth-climate relationships, developing statistical models of tree growth, extracting climatic signal, reconstructing and analysing climatic conditions of the remote past). This work will be finished at the end of 1999.

  7. John F. Pittman said

    It appears that CPS should have the ring widths divided by the latewood or even early wood density.

    Looking at Briffa said where the dates of optimal growth listed in quote above and this from Dr. Briffa appear to be in conflict with the quote you provided:

    “”>>On Mon, 3 Nov 1997, Keith Briffa wrote:

    >> I have been agonising for months that these results are not some

    >> statistical artifact of the analysis method but we can’t see how. For just

    >> two species (spruce in the western U.S. Great Basin area and larch in

    >> eastern Siberia) we can push the method far enough to get an indication of

    >> much longer term growth changes ( from about 1400) and the results confirm

    >> a late 20th century apparent fertilization! The method requires

    >> standardizing (localized mean subtraction and standard deviation division)

    >> by species/age band so we reconstruct relative (e.g. per cent change) only .

    >> We have experimented with integrating the different signals in basal area

    >> and density(after extracting intra ring ring width and density data where

    >> available) within a ‘flat mass’ measure which shows a general late 20th

    >> century increase – but whether this incorporates a defensible relative

    >> waiting on the different components (and what the relative carbon

    >> components are) is debatable. We now need to make some horrible simplistic

    >> assumptions about absolute carbon in these (relatively small) components of

    >> the total biomass carbon pool and imlpications for terrestrial and total

    >> carbon fluxes over the last few hundred years – and beyond! Without these

    >> implications we will have difficulty convincing Nature that this work is

    >> mega important.”

  8. Brian B said

    Probably a dumb and already answered question, but do we know that the Briffa divergence actually diverges from the local temp records corresponding to the tree ring series in his various papers?
    We know they diverge from the global adjusted temps records which he fit them to and which we also know are something of a mess. And presumably they diverge even from UAH during the period they overlap, but has anyone actually looked at the local rather than the “teleconnected” relationship of the divergence?
    Perhaps what diverged were local and global temps?

  9. Atomic Hairdryer said

    I get the feeling from some of the emails that there was a certain amount of friction between Briffa and other Hockey Players and he may have been under peer pressure to conform to the agreed consensus. The private emails do seem to show more concerns regarding the reliability and accuracy than the papers or press releases.

  10. Jeff Id said

    #8 type “circling yamal” in the search window on the left.

  11. Kenneth Fritsch said

    I get the feeling from some of the emails that there was a certain amount of friction between Briffa and other Hockey Players and he may have been under peer pressure to conform to the agreed consensus. The private emails do seem to show more concerns regarding the reliability and accuracy than the papers or press releases.

    I keep hearing that Briffa was kind of the voice of reason in these emails, but when I see what he had to say in those as cited by Jeff ID above I see a Briffa very willing to work from a conclusion. Please someone show me the “other” Briffa with email examples.

  12. hpx83 said

    Dear Jeff,

    Since you were nice enough to link me last time, I thought this might interest you. I ran through the GHCN dataset again, this time calculating average adjustments per year for the entire dataset. I can’t really figure out what the results mean, but doesn’t logic say that upwards adjustments should be just as common as downward adjustments? Shouldn’t the “average annual adjustment” over a longer timeperiod bounce around the zero line? Or is there some strange factor that I am not aware of that makes thermometers constantly give to low readings…..?

    Hoping you have better knowledge of statistics than I do, this dataset just keeps getting worse and worse…..

    // hpx

    http://savecapitalism.wordpress.com/2009/12/02/ghcn-database-adjustments/

  13. Ayrdale said

    “Hokeysticizated”…”unhockeysticizated” bear repeating…they may even make it into the OED eventually, but hokey and hockey need smoothing and flattening. Perhaps they may be a little less challenging if we came up with a verb meaning to smooth and flatten data a la Keith Briffa/Phil Jones … perhaps “crugating” ?

  14. dearieme said

    The bobbies are taking an interest.
    http://www.dailymail.co.uk/news/article-1232722/Professor-climate-change-scandal-helps-police-enquiries-researchers-banned.html

  15. Paul Linsay said

    Do these people even remotely understand the concept of noise? If someone has the data for these plots it would be interesting to make a distribution of the values. If I were a betting man I’d guess they are distributed as a Gaussian.

  16. David said

    Ross McKitrick had a good piece recently on the hockey stick:

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

    http://www.financialpost.com/opinion/story.html?id=2056988&p=1

    Also, check out what the historical temperature looked like before the hockey stick:
    http://www.theregister.co.uk/2009/11/30/crugate_analysis/print.html

  17. Kondealer said

    “The low interannual variability and the minimum occurrence of cold extremes during the 20th century, argue that the most recent decades of this long summer record represent the most favourable climate conditions for tree growth within the last four millennia.”

    Is Briffa blind, or just thick?

    We know it is not the former so it must be the latter.

    In fact anyone with half a brain would recognise from Figs, 5, 9 and 11. that Briffa’s statement is not supported by the evidence.

    On the otherhand maybe Briffa was been very clever by not wanting to have his name associated with a paper that so clearly contradicts his own and the other members of “The Team’s” work.

  18. Kondealer said

    Dearieme, unfortunately the article says they are treating him as a “victim”. More’s the pity. They should throw him in jail, to prevent further conspiracy, while an investigation into the real crime occurs.

  19. John F. Pittman said

    #11 K Fritsch you asked “I keep hearing that Briffa was kind of the voice of reason in these emails, but when I see what he had to say in those as cited by Jeff ID above I see a Briffa very willing to work from a conclusion. Please someone show me the “other” Briffa with email examples.”” There are others in the “context” post I did.

    Dr. Briffa emailed:

    Peck, you have to consider that since the TAR , there has been a lot of argument re
    “hockey stick” and the real independence of the inputs to most subsequent analyses is
    minimal. True, there have been many different techniques used to aggregate and scale
    data – but the efficacy of these is still far from established. We should be careful not
    to push the conclusions beyond what we can securely justify – and this is not much other
    than a confirmation of the general conclusions of the TAR . We must resist being pushed
    to present the results such that we will be accused of bias – hence no need to attack
    Moberg . Just need to show the “most likely” course of temperatures over the last 1300
    years – which we do well I think. Strong confirmation of TAR is a good result, given
    that we discuss uncertainty and base it on more data. Let us not try to over egg the
    pudding.
    For what it worth , the above comments are my (honestly long considered) views – and I
    would not be happy to go further . Of course this discussion now needs to go to the
    wider Chapter authorship, but do not let Susan (or Mike) push you (us) beyond where we
    know is right.

    Professor Keith Briffa,
    Climatic Research Unit
    University of East Anglia
    Norwich, NR4 7TJ, U.K.

  20. J. Peden said

    #16 David:”Also, check out what the historical temperature looked like before the hockey stick:
    http://www.theregister.co.uk/2009/11/30/crugate_analysis/print.html

    Well worth a view, nice style, too:

    A not unreasonable idea, you might think, since our energy (unless you live by a volcano vent) is derived from the sun.

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