Continuing Problems with Paleoclimate Proxies

Discussion in 'Environment & Conservation' started by Jack Hays, Jan 11, 2021.

  1. Jack Hays

    Jack Hays Well-Known Member Donor

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  2. Jack Hays

    Jack Hays Well-Known Member Donor

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  3. Jack Hays

    Jack Hays Well-Known Member Donor

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    The proxy madness continues.

    CLINTEL’s critical evaluation of the IPCC AR6

    Posted on May 13, 2023 by curryja | 22 comments
    by Judith Curry

    Clintel has published a new report entitled “The Frozen Climate Views of the IPCC: Analysis of the AR6.”

    Zombie Hockey Stick

    Shortly after publication of AR6 WGI, I spotted some comments in twitter regarding the resurrection of the Hockey Stick. After wondering “what fresh new Hockey Stick hell is this?”, I didn’t investigate further.

    Well the Clintel Report did the work for me. Subtitle for Chapter 2:

    “A big surprise in the new IPCC report is the publication of a brand new hockey stick. The IPCC once again has to cherry pick and massage proxy data in order to fabricate it. Studies that show larger natural climate variations are ignored.”

    Excerpts from the Chapter:

    <begin quotes>

    The PAGES 2k group is specialised in climate reconstructions and back in 2013 was comprised of the majority of all active paleoclimatologists. The PAGES 2k Consortium (2013) published a reconstruction in which parts of the first millennium were occasionally as warm as present-day

    In 2019, PAGES 2k published a new version of the temperature development of the past 2000 years (PAGES 2k Consortium, 2019)11. Surprisingly, it differed greatly from the predecessor version. Even though the database had only mildly changed, the pre-industrial part was now suddenly nearly flat again. The hockey stick was reborn.

    The new hockey stick was immediately incorporated into the AR6 report (IPCC, 2021). Among the lead authors of AR6 chapter 2 is Darrell S. Kaufman who is a co-author of the new hockey stick in the PAGES 2k Consortium (2019). This is probably not a coincidence.

    Evidence suggests that a significant part of the original PAGES 2k researchers could not technically support the new hockey stick and seem to have left the group in dispute. Meanwhile, the dropouts published a competing temperature curve with significant pre-industrial temperature variability (Büntgen et al., 2020). On the basis of thoroughly verified tree rings, the specialists were able to prove that summer temperatures had already reached today’s levels several times in the pre-industrial past. However, the work of Ulf Büntgen and colleagues was not included in the IPCC report, although it was published well before the editorial deadline.

    Like its predecessor, the new hockey stick by PAGES 2k 2019 is based on a large variety of proxy types and includes a large number of poorly documented tree ring data. In many cases, the tree rings‘ temperature sensitivity is uncertain. For example, both PAGES 2k Consortium (2013) and PAGES 2k Consortium (2019) used tree ring series from the French Maritime Alps, even though tree ring specialists had previously cautioned that they are too complex to be used as overall temperature proxies.

    In contrast, Büntgen et al. (2020) were more selective, relied on one type of proxy (in this case tree rings) and validated every tree ring data set individually. Their temperature composite for the extra-tropical northern hemisphere differs greatly from the studies that use bulk tree ring input.

    In some cases, PAGES 2k composites have erroneously included proxies that later turned out to reflect hydroclimate and not temperature. In other cases, outlier studies have been selected in which the proxies exhibit an anomalous evolution that cannot be reproduced in neighbouring sites (e.g. MWP data from Pyrenees and Alboran Sea in PA13). Outliers can have several reasons, e.g. a different local development, invalid or unstable temperature proxies, or sample contamination.

    Steve McIntyre has studied the PAGES 2k proxy data base in great detail and summarized his criticism in a series of blog posts on his website Climate Audit. For example, the PAGES 2k Consortium (2019) integrated a tree ring chronology from northern Pakistan near Gilgit (“Asia_207”) which shows an extreme closing uptick. Incorporation of data series like this strongly promote the hockey stick geometry of the resulting temperature composite. McIntyre analysed the original tree ring data and found that the steep uptick in the Asia_207 chronology is the result of questionable data processing. When calculating the site chronology using the rcs function from Andy Bunn’s dplR package, the uptick surprisingly disappears. In fact, the series declines over the 20th century.

    Conclusion: The resurrected hockey stick of AR6 shows how vulnerable the IPCC process is to scientific bias. Cherry picking, misuse of the peer review process, lack of transparency, and likely political interference have led to a gross misrepresentation of the pre-industrial temperature evolution.
     
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  4. Jack Hays

    Jack Hays Well-Known Member Donor

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    There are some proxies that the alarmists don't publicize.
    California’s Mean Annual Temps Were Up To 3.8°C Warmer Than Today During The Last Glacial
    By Kenneth Richard on 15. May 2023

    Share this...
    From 14,000 to 45,000 years ago, when the atmospheric CO2 values were said to be under 200 ppm, California lakes record millennial-scale mean annual air temperature (MAAT) variations of over 12°C and intervals when it was nearly 4°C warmer than modern.
    Per a new paleotemperature reconstruction (Olson et al., 2023) from a California lake, there were periods during the last glacial when MAATs were both significantly colder (11.8°C) and warmer (23.9°C) than today (20.1°C).

    The Holocene, ~250-275 ppm CO2, has also had periods when paleotemperatures were multiple degrees warmer than modern.

    [​IMG]

    Image Source: Olson et al., 2023
    . . . .
     
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  5. Jack Hays

    Jack Hays Well-Known Member Donor

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    New Study: The Lowest Tibetan Plateau Glacial Temps Were Still 3°C Warmer Than Today
    By Kenneth Richard on 18. May 2023

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    “Even the lowest pollen derived Pleistocene MAT [mean annual temperature] estimates are still ∼3.5 to 2.5 °C warmer than the modern KPB MATs [Kunlun Pass Basin] of ∼ −6.1 °C.” – Schwarz et al., 2023
    The Kunlun Pass Basin (KPB) in the northeastern Tibetan Plateau is the largest alpine permafrost region on Earth.

    About 4 million years ago, during the Pliocene epoch, this location was permafrost-free. The mean annual temperatures (MAT) were more than 14°C warmer than they are today (Schwarz et al., 2023).

    While scientists have sometimes claimed the higher Pliocene CO2 concentrations (~420 ppm) were at least partly responsible for this warmth, it is well established that CO2 concentration changes follow temperature changes by centuries to millennia in paleoclimate reconstructions (Fischer et al., 1999;Monnin et al., 2001; Caillon et al., 2003; Stott et al., 2007; Kawamura et al., 2007). Since causes cannot lag effects, this largely precludes CO2 as a driving mechanism for ancient temperature fluctuations.

    To further clarify CO2 concentrations are not a climate driver, pollen records in the KPB indicate that even the lowest glacial temperatures and lowest CO2 concentrations (“below 200 ppm”) of the Quaternary ice age (last ~2.5 million years) were still “~3.5 to 2.5−°C warmer” than they are with today’s CO2 (~420 ppm) concentrations (Schwarz et al., 2023).

    [​IMG]

    Image Source: Schwarz et al., 2023
     
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  6. Jack Hays

    Jack Hays Well-Known Member Donor

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    The Canonized 100,000- And 41,000-Year Glacial-Interglacial Climate Cycles May Never Have Existed
    By Kenneth Richard on 6. July 2023

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    A new study identifies a major correlation flaw in paleoclimate research. The “missing” correlations are more common than correlations.
    In the past we have identified major contradictions in the widely-accepted contention that the entire Earth freezes its way into glacial climates that cyclically last roughly 100,000 years, interrupted by ~10,000-year interglacials.

    This 100,000-year glacial-interglacial cycle supposedly lasted only 41,000 years until the last 900,000 years or so.

    But many recent studies show the climate was warmer than today during what has been referred to as the last glacial period, when CO2 was allegedly under 200 ppm. For example:

    New Study: The Lowest Tibetan Plateau Glacial Temps Were Still 3°C Warmer Than Today


    California’s Mean Annual Temps Were Up To 3.8°C Warmer Than Today During The Last Glacial


    New Study Finds Australian Sea Temperatures Multiple Degrees Warmer Than Today During The Last Glacial


    Another Study Says Europe Was At Times Warmer During The Last Glacial When CO2 Levels Were 40% Lower


    10 Recent Studies Affirm It Was Regionally 2-6°C Warmer Than Today During The Last Glacial


    And now another analysis (Jonas, 2022) points out the lack of correlation between Milankovitch cycles and climate and the chaotic, widely varying, non-cyclical nature of glacial and interglacial climate durations and amplitudes. The non-correlations, or “missed cycles,” occur just as or more often than the ones that “hit.”

    The conclusion is that “there never was a 41,000-year cycle,” and “there is no 100,000-year cycle” either.

    Instead, Earth has operated and continues to operate as a “coupled, non-linear, chaotic system.”

    [​IMG]

    Image Source: Jonas, 2022
     
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  7. Jack Hays

    Jack Hays Well-Known Member Donor

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    Steve McIntyre is back, and that's bad news for Michael Mann.
    MBH98 Confidence Intervals
    Nov 10, 2023 – 10:55 AM
    Continued from here. (Please see #158.)

    The Dirty Laundry residual datasets for AD1000, AD1400 and AD1600 were each calculated using Mann’s “sparse” instrumental dataset, but the resultant sigmas and RE(calibration) statistics don’t match reported values. In contrast, the Dirty Laundry residual dataset for the AD1820 step, which was calculated by Tim Osborn of CRU because Mann “couldn’t find” his copy of the AD1820 residual data, used a different MBH98 target instrumental dataset – the “dense” instrumental series.

    Question: is it possible that Mann had two versions of the residual data: sparse and dense? And that he chose the dense version for MBH98 statistics (sigma, RE_calibration) because it yielded “better” statistics, but inadvertently sent the sparse version (with worse values) to Osborn?

    This appears to be exactly what happened. If one uses the Dirty Laundry values for the reconstruction in 1902-1980 versus the MBH98 dense temperature series, one gets an exact replication of reported MBH98 calibration RE and sigma (standard error of residuals) for the AD1400 and AD1600 step and reported MBH99 calibration RE for the AD1000 step.

    [​IMG]

    Conclusion: We KNOW that MBH98 calculated residual series using the sparse target because they were sent to Osborn in the Dirty Laundry email and shown in the MBH99 submission Figure 1a. We KNOW that MBH98 calculated residual series using the dense target because of the reported RE_calibration and sigma values in MBH98. The corollary is that MBH98 calculated two sets of residual series and then selected the “better” values for display without disclosing the worse values. Or the selection operation.

    MBH99 confidence intervals are related to MBH98 confidence intervals, but different. They were a longstanding mystery during the heyday of Climate Audit blog. In next post, I’ll review MBH99 confidence intervals. We’re a bit closer to a solution and maybe a reader will be able to figure out the balance.

    Over and above, this particular issue is another even more fundamental issue: the use of calibration period residuals to estimate confidence intervals when there is a massive failure of verification period r^2 values. Prior to Climategate, I had written several posts and comments in which I had raised the issue and problem of massive overfitting in the calibration period through a little discussed MBH98/99 step involving a form of inverse regression. (Closer to PLS regression than to OLS regression – some intuitions of OLS practitioners have to be set aside.) There are some very interesting issues and problems arising from this observation. And even some points of potential mathematical interest. I’ll try to elaborate on this in a future post. . . .
     
    Last edited: Nov 23, 2023
  8. Jack Hays

    Jack Hays Well-Known Member Donor

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    Here's the thread being pulled from the sweater.
    « Mann’s “Dirty Laundry”
    MBH98 Confidence Intervals »
    “Dirty Laundry” Residuals
    Continued from previous post link.

    The data associated with the Climategate “dirty laundry” email had other interesting information on Mann’s calculation of confidence intervals and the related calculation of RE statistic. This post draws heavily on offline comments by Jean S and UC, both long before and after Climategate.

    The left panel below is Tim Osborn’s summer 2003 plot of the AD1000 residuals in one of the “dirty laundry” datasets sent to him by Mann. It matches the AD1000 data in the right panel – Figure 1a in the submission version of Mann et al 1999. UC had noticed this figure in submission version in 2006 or so.

    [​IMG]

    While the plot of calibration residuals was not carried forward into the published version of Mann et al 1999, an identical figure showing the spectrum of calibration residuals appears in both versions (see below). This almost certainly precludes an unreported switch of the calculation of calibration residuals between submission version and publication (though, with Mann et al, nothing can be excluded.)

    [​IMG]

    Here’s the rub: the standard errors (RE_calibration) values reported in MBH98 and MBH99 are lower (much higher) than values calculated using the Dirty Laundry data.

    The RE_NH_cal(ibration) values for MBH98 were reported in its original statistical SI (link) and, for MBH99, in its running text. The MBH98 sigmas (standard error of residuals) for each step can be extracted from the archived stepwise reconstruction mannnhem.dat (NOAA link). The standard error of residuals in the Climategate “dirty laundry” datasets (AD1000, AD1400, AD1600) can be trivially calculated. Osborn did so in his August 2003 Climategate I document entitled Mann uncertainty.docx. I verified the calculation – values are shown below. The calibration RE (RE_cal) is trivially calculated as 1- (se_residuals/sd_obs)^2. (The standard deviation of the target observation data used in the above Dirty Laundry datasets is 0.2511.)

    [​IMG]

    Conclusions:

    The Dirty Laundry residual datasets do NOT match the reported RE calibration or sigmas (standard error of residuals) reported for MBH98 (AD1400, AD1600) or the RE calibration reported for MBH99, even though the Dirty Laundry residuals for AD1000 match Figure 1 in the MBH99 submission. The calculation of MBH confidence intervals was a standing puzzle in pre-Climategate discussion – see review here – and never fully resolved. While the reported numbers do not match the data in the Dirty Laundry residual datasets, the glimpses of the underlying reconstructions in the Dirty Laundry datasets provides data that can be used to finally resolve the calculation of MBH98 confidence intervals. More on this in next post. See here . . .
     
  9. Bowerbird

    Bowerbird Well-Known Member

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    upload_2023-11-24_14-49-47.jpeg

    Talk about dragging up old news. 15 years. That is how long people have been examining this data. And somehow in all that time no one has noticed this before?
     
  10. Bullseye

    Bullseye Well-Known Member

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    you do understand that climate progression goes back centuries, yes? Many trends don't even appear for decades or centuries.
     
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  11. Jack Hays

    Jack Hays Well-Known Member Donor

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    Oh, but they have noticed it. The fact that you couldn't be bothered to follow the topic does not mean that others were similarly uncurious or interested.
     
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  12. Sunsettommy

    Sunsettommy Well-Known Member

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    Yeah, more evidence of Dr. Manns incompetence is brought out that is what she is trying hard to ignore.
     
  13. Jack Hays

    Jack Hays Well-Known Member Donor

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    I'm not sure it was incompetence. IMHO he fudged to get what he considered the "right" answer and one that would boost his career. In that regard he calculated correctly.
     
  14. bringiton

    bringiton Well-Known Member

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    It's not incompetence. It is obvious dishonesty.
     
  15. bringiton

    bringiton Well-Known Member

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    :lol: So, if they can just stonewall long enough, anti-fossil-fuel scaremongers can make their lies into "the consensus"...?

    Somehow, I kinda figured it'd be something like that...
    No, because evil, lying scum like Michael Mann delay releasing their data or the algorithms they use to manipulate and falsify it for years, or even decades, if they can ever be compelled to release them at all.
    Honest climate scientists noticed there was an issue right away. They just couldn't get the data and algorithms from Mann, so they couldn't tell exactly how the manipulation and falsification was being done.
     
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  16. Bullseye

    Bullseye Well-Known Member

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    Somewhat contradictory that she's argued, attacked, and demeaned those of us whose view on GW are more moderated and balanced and puts an insulting image on a post that calmly explains the issue. Raises the question as whether she's interested in discuss or name calling and insults.
     
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  17. Jack Hays

    Jack Hays Well-Known Member Donor

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    "Uninterested" intended. My apologies.
     
  18. Jack Hays

    Jack Hays Well-Known Member Donor

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    Bingo.
     
  19. Sunsettommy

    Sunsettommy Well-Known Member

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    I agree there is dishonesty in it but some of his incompetence has been exposed in numerous Climate Audit postings.
     
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  20. Jack Hays

    Jack Hays Well-Known Member Donor

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    This is starting to look like research misconduct.
    Mann’s Other Nature Trick
    Nov 24, 2023 – 2:51 PM
    In today’s post, I will report on some excellent work on MBH98 by Hampus Soderqvist, who discovered an important but previously unknown Mike’s Nature Trick: Mann’s list of proxies for AD1400 and other early steps was partly incorrect (Nature link now dead – but see NOAA or here). Mann’s AD1400 list included four series that were not actually used (two French tree ring series and two Moroccan tree ring series), while it omitted four series that were actually used. This also applied to his AD1450 and AD1500 steps. Mann also used an AD1650 step that was not reported.

    Soderqvist’s discovery has an important application.

    The famous MBH98 reconstruction was a splice of 11 different stepwise reconstructions with steps ranging from AD1400 to AD1820. The proxy network in the AD1400 step (after principal components) consisted 22 series, increasing to 112 series (after principal components) in the AD1820 step. Mann reported several statistics for the individual steps, but, as discussed over and over, withheld the important verification r2 statistic. By withholding the results of the individual steps, Mann made it impossible for anyone to carry out routine statistical tests on his famous reconstruction.

    However, by reverse engineering of the actual content of each network, Soderqvist was also able to calculate each step of the reconstruction – exactly matching each subset in the spliced reconstruction. Soderqvist placed his results online at his github site a couple of days ago and I’ve collated the results and placed them online here as well. Thus, after almost 25 years, the results of the individual MBH98 steps are finally available. . . .

    Our response has always been that the relevant question was not whether the hockey stick pattern of the stripbark bristlecones was a distinctive pattern within the North American tree ring network, but whether this pattern was local and specialized, as opposed to an overall property; and, if local to stripbark bristlecones, whether the stripbark bristlecones were magic world thermometers. The 2006 NAS panel recommended that stripbark bristlecones be avoided in temperature reconstructions, but their recommendation was totally ignored. They continued in use in Mann et al 2008, PAGES2K and many other canonical reconstructions, none of which are therefore independent of Mann et al 1998-99.

    While most external attention on MBH98 controversy has focussed on principal component issues, when I reviewed the arc of Climate Audit posts in 2007-2008 prior to Climategate, they were much more focused on questions pertaining to properties of the inverse regression step subsequent to the principal components calculation and, in particular, to overfitting issues arising from inverse regression. Our work on these issues got sidetracked by Climategate, but there is a great deal of interesting material that deserves to be followed up on.
     
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  21. Jack Hays

    Jack Hays Well-Known Member Donor

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    Mann's work is being deconstructed.
    MBH98 Weights – an Update
    Nov 26, 2023 – 2:10 PM
    In numerous ancient Climate Audit posts, I observed that all MBH98 operations were linear and that the step reconstructions were therefore linear combinations of proxies, the coefficients of which could be calculated directly from the matrix algebra (described in a series of articles.) Soderqvist’s identification of the actual proxies enables calculation of the AD1400 weights by regression of the two “glimpses” of the AD1400 step (1400-1449 in the spliced reconstruction and 1902-1980 in the Dirty Laundry data) against the proxy network. The regression information is shown in an Appendix at end of this post.

    The figure below shows the weights for (scaled) proxies as follows: left – weights from my previous (ancient) calculations from “first principles”; right – from regression of reconstruction “glimpses” against Soderqvist identification network.

    I haven’t yet tried to retrace my linear algebra using the new identification. The linear algebra used in the diagram at left also reconciles to five nines to the Wahl-Ammann calculation. So it can safely be construed as the weights for the AD1400 network as listed in the Nature SI, but not the actual MBH98 network, the weights of which are shown on the right.

    [​IMG]

    Within the overall similarity, there are some interesting differences in weights arising from the use of four lower order NOAMER (pseudo-) PCs rather than four tree ring series from Morocco and France. The problematic Gaspe series (what Mark Steyn referred to in his deposition as the “lone pine”) receives nearly double the weighting in the MBH98 data as actually used, as opposed to the incorrect listing at Nature. Also, the NOAMER PC6 is almost as heavily weighted as the notorious Mannian PC1. It will be interesting to see how heavily the Graybill stripbark bristlecones and other data that Mann had analysed in his CENSORED directory feature in this other heavily weighted PC. My guess is that combination of principal components and inverse regression will show the heavy weighting of stripbark bristlecones and downweighting of other data that we pointed out almost 20 years ago. . . . .
     
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  22. Sunsettommy

    Sunsettommy Well-Known Member

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    HA HA HA HA HA......

    How can anyone still support Mann's pseudoscience paper when it has too many problems in it.

    The paper is garbage therefore should be considered refuted and retracted.
     
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  23. bringiton

    bringiton Well-Known Member

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    It should have been retracted the moment he refused to provide his data, because that proved he was lying about it.
     
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  24. Jack Hays

    Jack Hays Well-Known Member Donor

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    So much for the hockey stick.
    New Study: The ‘Global Tropics As A Whole’ Were As Warm Or Warmer Than Today 10,000 Years Ago
    By Kenneth Richard on 4. December 2023

    “…by about 10 kyr ago, regional MST values consistently approached or exceeded today’s value of about 23°C” – Baxter et al., 2023
    According to a new temperature reconstruction published in Nature, the Horn of Africa and “global tropics as a whole” were “1.6°C warmer than today” throughout the Early and Middle Holocene. This is “consistent with compilations from the global tropics.”
    This region’s mean surface temperature (MST), 23°C, is nearly the coldest in the last 10,000 years. It was as warm or warmer than today not only 10,000 years ago, but also from about 55,000 to 30,000 years ago, when Earth was experiencing glacial conditions and CO2 concentrations were said to be below 200 ppm.
    [​IMG]

    Image Source: Baxter et al., 2023
     
  25. Jack Hays

    Jack Hays Well-Known Member Donor

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    After decades of cover-up, the truth is coming out.
    Discovery of Data for One of the “Other 26” Jacoby Series
    Dec 12, 2023 – 1:32 PM
    We’ve long discussed the bias imparted by ex post selection of data depending on whether it went up in the 20th century. Likening such after-the-fact selection to a drug study carried out only on survivors.

    The Jacoby and d’Arrigo 1989 network was a classic example: the original article reported that they had sampled 36 northern treeline sites, from which they selected 10 with the “best record…of temperature-influenced tree growth”, to which they added a chronology of Gaspe cedars that was far south of the northern treeline at low altitudes.

    [​IMG]

    In 2004 and 2005, I made a determined effort (link) to obtain the measurement data for the 26 sites that weren’t included in the final calculation. Jacoby refused. I tried over and over to get this data, but was never successful.

    Gordon Jacoby died in October 2014. In June 2014, a few months prior to his death, the Lamont Doherty Earth Observatory unit of Columbia University (Jacoby’s employer) archived a large collection of tree ring data collected by Jacoby and associates (link). By then, it was 25 years since publication of Jacoby and D’Arrigo 1989 and 8 years since publication of D’Arrigo et al 2006.

    By then, the paleoclimate community had “moved on” to the seeming novelties of PAGES2K. A few Jacoby and d’Arrigo series re-appeared in PAGES2K. I wrote a couple of articles on these new Jacoby and d’Arrigo avatars: on their Central Northwest Territories (Canada) series in January 2016 here; and on their Gulf of Alaska series in February 2016 here and here. But the articles attracted little interest. Jacoby and D’Arrigo had successfully stonewalled availability of data until no one was interested any more. Not even me.

    However, while recently refreshing myself on ancient MBH98 issues, I discovered something interesting: buried in the dozens of measurement data sets in the belated 2014 archive was one of the datasets that Jacoby had withheld back in 2004. (Thus far, I’ve only found one, but there may be others.) It was a northwest Alaska dataset collected in 1979 – . What did the withheld data show? Despite the passage of time, I was interested.

    Long-time readers will undoubtedly recall Jacoby’s classic data refusal:

    We strive to develop and use the best data possible. The criteria are good common low and high-frequency variation, absence of evidence of disturbance (either observed at the site or in the data), and correspondence or correlation with local or regional temperature. If a chronology does not satisfy these criteria, we do not use it. The quality can be evaluated at various steps in the development process. As we are mission oriented, we do not waste time on further analyses if it is apparent that the resulting chronology would be of inferior quality.

    If we get a good climatic story from a chronology, we write a paper using it. That is our funded mission. It does not make sense to expend efforts on marginal or poor data and it is a waste of funding agency and taxpayer dollars. The rejected data are set aside and not archived.

    As we progress through the years from one computer medium to another, the unused data may be neglected. Some [researchers] feel that if you gather enough data and n approaches infinity, all noise will cancel out and a true signal will come through. That is not true. I maintain that one should not add data without signal. It only increases error bars and obscures signal.

    As an ex- marine I refer to the concept of a few good men.

    A lesser amount of good data is better without a copious amount of poor data stirred in. Those who feel that somewhere we have the dead sea scrolls or an apocrypha of good dendroclimatic data that they can discover are doomed to disappointment. There is none. Fifteen years is not a delay. It is a time for poorer quality data to be neglected and not archived. Fortunately our improved skills and experience have brought us to a better recent record than the 10 out of 36. I firmly believe we serve funding agencies and taxpayers better by concentrating on analyses and archiving of good data rather than preservation of poor data.

    They may also recall Rosanne D’Arrigo’s remarkable 2006 presentation to a dumbfounded NAS Panel, to whom she explained that you had to pick cherries if you want to make cherry pie, as I reported at the time (link):

    D’Arrigo put up a slide about “cherry picking” and then she explained to the panel that that’s what you have to do if you want to make cherry pie. The panel may have been already reeling from the back-pedalling by Alley and Schrag, but I suspect that their jaws had to be re-lifted after this. Hey, it’s old news at climateaudit, but the panel is not so wise in the ways of the Hockey Team. D’Arrigo did not mention to the panel that she, like Mann, was not a statistician, but I think that they already guessed.

    D’Arrigo et al (2006) was relied upon by both NAS Panel and IPCC AR4, but, once again, D’Arrigo refused to provide measurement data – even when politely asked by Gerry North, chair of the NAS Panel. . . .
     
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