Today’s article is about one of the D’Arrigo et al 2006 datasets.
D’Arrigo et al 2006, then under submission, had been cited in drafts of the IPCC Fourth Assessment Report. I had been accepted as an IPCC reviewer and, as an IPCC reviewer, I asked IPCC to make the data available to me or to ask the lead author to make the data available. That prompted a vehement refusal that I documented in March 2007 (link). Readers unfamiliar with the severity of data obfuscation by climate science community should read that exchange. (Some further light on the campaign emerged later in the Climategate emails.
D’Arrigo et al 2006 calculated more than a dozen new regional chronologies, but refused to archive or provide the digital chronologies until April 2012, more than six years later (by which time the paleo field purported to have “moved on”. Also, in April 2012, more than six years later, D’Arrigo et al provided information (somewhat sketchy) on which sites had been used in the various reconstructions, but measurement data for many of the sites was unavailable, including (and especially) the sites that had been sampled by D’Arrigo, Jacoby and their associates. Much of this data was archived in April 2014, a few months before Jacoby’s death. But even this archive was incomplete.
By then, D’Arrigo et al 2006 was well in the rear view mirror of the paleo community and there has been little, if any, commentary on the relationship of the belated and long delayed 2014 data archive to the 2006 article.
In several recent posts, I’ve discussed components of D’Arrigo’s Northwest Alaska (NWNA) regional chronology, which, prior to 2012, had only been available in the muddy form shown below.
The NWNA series goes from AD1297 to AD2000 and closes on a high note – as shown more clearly in the top panel below, which re-plots the post-1800 period of the NWNA chronology (RCS version; STD version is very similar.) Also shown in this figure (bottom panel) is the post-1800 period of the chronology (ModNegExp ) for the Dalton Highway (ak104) site, the only component of the NWNA composite with values in the 1992-2000 period (shown to right of red dashed line.)
Look at the difference right of the dashed line at AD1990. In the underlying Dalton Highway data, the series ends at almost exactly the long-term average, whereas the same data incorporated into D’Arrigo’s NWNA regional composite closes at record or near-record highs for the post-1800 period.
If the 1992-2000 Dalton Highway data doesn’t show record highs for the site chronology, then it is implausible to claim that it shows record highs for the regional chronology. So what’s going on here?
My guess is that the regional chronology has mixed sites with different average widths and that their rudimentary statistical technique didn’t accommodate those differences. If so, this would be the same sort of error that we saw previously with Marcott et al 2013, in which there was a huge 20th jump without any increase in component series (simply by a low value series ending earlier.) Needless to say, these errors always go in a hockey stick direction.
Climate Audit 
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So now we have D’Arrigo admitting out loud that 26 sites of her and Jacoby’s 36 were tossed simply because they didn’t think the government would like the “story” they told. Steve found one of the 26 missing sites and it confirmed his fears that D’Arrigo was telling the truth about her cherry pie method. Then, on one of the 10 “good” Jacoby sites Mann somehow lost the data from 1296-1500, which contrary to his claim is archived at NOAA since the early 1990s. That missing data happens to contain a spurious hockey stick blade. But it’s not in the 20th century.
On top of post hoc site selection and data truncations Steve shows in his last post, and in many others, that the shape of the site’s plot is highly sensitive to the data processing technique. I mean completely sensitive. And then using ensembles all these freedoms of site selection, truncations and choice of analysis method, can be used in combination to create virtually any story that is ordered up to the kitchen. Am I missing something?
Ron:
You’re missing that proxy selection is not a “now” issue. Has been discussed for almost two decades. Including remarks by the proxy pickers, admitting (while rationalizing) the proxy selection method.
For what it’s worth, I’m actually 90% on Steve’s side here. But acting like this is some big new revelation is silly, and shows a lack of reading the blog.
Plus really that’s more with the article a few days ago. This article is more about finding a repeat of the Marcott method error. And how, failure to share the proxy data meant that we didn’t find the Marcottian issue until now. That’s more what this article is about.
Anon, I respect your valuable contributions and we probably agree on 98% regarding tree rings as temperature proxies, but I disagree with your implication that old equals unimportant. The Climategate investigations were whitewashes. The upcoming Mann v Steyn trial might be the closest we ever get to a public hearing. The issues need to be simplified and crystal clear, (including new finds), if we would like to see the manufactured consensus fall.
Judith Curry just commented that she will be a witness at the Steyn trial, likely in regarding how Mann dishes it out but can’t take it. I am hoping Steve will also be there but afraid he has a much bigger part, too big to condense. It’ll be critical what gems are chosen.
Knowing Mann will use his credential and support of the expert field to say he was wronged, it will be critical to show that Mann’s support does not necessarily equate with his legitimacy. Steyn will be able to partially dig into this by quotes from his book, The Disgrace to the Profession. But they are indirect hits.
I would go after Mann’s support group by presenting the Climategate emails that demonstrate the level of their collusion to circle the wagons against nosey skeptics, for which our host was numero uno.
I happen to find one email today that I’m sure Steve has read. Phil Johns writes to Christian Azar of Chalmers U. but cc’s 20 others and addresses one of them, Steve Schneider, editor and chief of the journal Climate Change. Jones is clearly corraling the community to persuade Schneider that is fine to stone wall McIntyre’s request for MBH data and code, which Jones claims they don’t need.
http://assassinationscience.com/climategate/1/FOIA/mail/1074277559.txt
This is exactly the type of behavior one now suspects Fauci used to corral the Proximal Origins authors and others. It is the most poisonous venom to truth an science and is understandable by a third grader, group scheming.
Here Steve and TCO and other openly discuss the issues dealing with Steve Schneider in a post a 1-1/2 years after Jones’s email to Scheider. https://climateaudit.org/2005/08/27/science-editorial/
Funny that at the end of Jones’s email Azar replies that it’s generally good to share whatever is needed for reproducibility. Clearly he does not have a clue Jones was not really asking him.
Ron _ i saw J curry’s comment that she will testify. However, I recall that the only expert that made id through the dalbert standard was the statistican. Curry did not pass the daubert standard since the case deals with whether Simberg/steyn knowingly made false statements therefore curry wasnt an expert on what Steyn know ie curry maybe an expert but not an expert on what either simberg or steyn knew
Following your first link, in the comments you said back in March 2007:
“Astonishingly, in the entire corpus of the four IPCC assessment reports, there is no intermediate-complexity exposition of exactly how doubled CO2 physically connects to 2.5 deg C increased temperature that would explain the issue to readers who are interested in understanding the matter from first principles”
As far as I’m aware, we still await such an exposition.
I think the first order hand-wavy explanation is greenhouse effect (re-radiation, giving partial “blanket). Plus the amplification effect of higher humidity (generated by the previous sentence).
I do agree that simplified conceptual energy models, would be good, as a further complication. (Although I think expecting them to give the same numerical result is unreasonable.) Unfortunately, warmers rely on the GCMS instead, which are really complex systems. Be nice for something in between. Like in the earl business where there are some good intuitive explanations (deeper gassier, seal types, etc.) along with the ornate 4-D seismic and gamma traces.
Then again, this article isn’t about that. And we can’t litigate every issue in every article. Asking for some info on how Marcott’s doing would be closer. 😉
The attempts to stitch together series with different begin/end dates is so lacking in rigor. ugh. And causes all sorts of chaos.
The cult of Michael Mann continues at the BBC: https://www.bbc.co.uk/sounds/play/m001qw93
Long time no chat.
JohnA is the only one (after Steve) who has read the blog more than I. Still remember attack/yap dog Bender saying to read the blog…and I was all like, I’m saltier than you, young pup!
John A and Anonymous, At the Mann vs Steyn and Simberg trial currently proceeding Mark Steyn questioned Mann on the stand about his use of tree ring proxies in the hockey stick. Although Steyn did not know enough to recognize evasions, (follow the pea), Mann made what I believe to be inaccurate statements in his replies.
Mann said that the divergence problem only applied to Briffa’s MXD but that all the other tree rings track instrumental temperature and do not have a divergence problem. Mann also said that he only used tree ring data up to 1980 because that was all the data that was available at the time. Mann said the he showed instrumental and tree ring plots only side by side when I know that even in MBH98/99 that he padded the last twenty years of the tree ring plots with instrumental data as his smoothing technique to give an upturn to the end that would have otherwise made a downturn using conventional padding methods. Can you supply more expert opinions after listening to Mann’s verbatim testimony re-enacted here at minute 53:35 onwards? Thanks. https://climatechangeontrial.com/ep-7-mann-ann/
Thanks for the link. I’d been following live when time allowed using the court webex. This is much better!
Should any of Mann’s models be able to predict the mid-century decline in temperature? There was no decline in greenhouse gas emissions so there should be no correlation there. The decline has regularly been ascribed to the effects of smog.
https://investigativeeconomics.substack.com/p/michael-manns-hockey-stick-graph
fwiw
I though S McIntyre did an excellent job on his testimony in the Mann vs Simberg trial.
very calm, soft spoken yet extremely good recall on specifics, especially on cross, very professional presentation,
compare and contrast with mann’s self conclusionary statements on the accuracy on mbh98 & 99.
During mann’s direct testimony by Williams, Mann commented that the residuals (r2?) had little or no meaning. With Wyner, McIntyre, McKintrick and someone else stating the R2 stat was 0.02, it should have put serious question Mann’s willingness to disclose.
One last point that McIntyre made that was telling was the required disclosure of all adverse information which was sorely lacking in both mbh98 & 99
Ref to Hockey Stick; Mann
The field is mostly junk science, unfortunately. Same problem with nutritional research.
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