A fascinating, hot-off-the-presses story emerges from the emails that were hacked yesterday from the University of East Anglia’s Hadley Climatic Research Centre. It is one of many exchanges that shed light on the priority that the global warming alarmists give to politics and career advancement over science.
The story began when Steve McIntyre, the same researcher who was largely responsible for destroying Michael Mann’s “hockey stick” graph purporting to show unprecedented warming in the 20th century, turned his attention to a famous article published by Keith Briffa of East Anglia’s CRU in 2000. This article analyzed the diameters of tree rings, including rings from an area called Yamal in Siberia, and conveniently generated another hockey-stick shaped graph. You can read an account of the ensuing controversy here. McIntyre’s work appeared to show that Briffa had cherry-picked trees in order to get the result he was looking for. One fact that this story highlights is that global warming alarmists publish their results in scientific journals, but refuse to make the underlying data publicly available so that the validity of their analyses can be checked.
McIntyre’s revelations caused a firestorm of controversy, in response to which the alarmist community circled its wagons to fend off the threat from an outsider. This process can be clearly seen in the East Anglia emails.
The alarmists’ effort to respond to McIntyre was complicated by the fact that Briffa had been ill and undergone surgery, and was then recuperating. So several of them wrote to Briffa’s co-author, Tim Osborn, for advice on how to respond to McIntyre’s critique. Osborn replied on September 29, 2009:
Hi Mike and Gavin, thanks for your emails re McIntyre, Yamal and Keith. I’ll pass on your best wishes for his recovery when I next speak to Keith. He’s been off almost 4 months now and won’t be back for at least another month ….
Regarding Yamal, I’m afraid I know very little about the whole thing — other than that I am 100% confident that “The tree ring data was hand-picked to get the desired result” is complete crap. Having one’s integrity questioned like this must make your blood boil….
Apart from Keith, I think Tom Melvin here is the only person who could shed light on the McIntyre criticisms of Yamal. But he can be a rather loose cannon and shouldn’t be directly contacted about this….
So: these scientists don’t really have any idea whether McIntyre’s critique of Briffa’s work is correct or not. Even Briffa’s co-author professes ignorance. There is one person they could approach who could “shed light on the McIntyre criticisms of Yamal.” But they don’t do it. Why? Because “he can be rather a loose cannon and shouldn’t be directly contacted….” In other words, his loyalty to the cause of climate alarmism may not be absolute. This is much like the case noted here where Michael Mann, one of the recipients of the above email, warns against sharing information with someone named Andy because he is “not as predictable as we’d like.”
Despite having no idea what the facts are, the alarmists don’t hesitate to formulate a position. Thus, on the next day, September 30, Osborn writes:
Keith’s temporarily come in to get a handle on all this, but it will take time. Likely outcome is (1) brief holding note that no cherry-picking was done and demonstrating data selection is defendable by our time tomorrow; (2) longer piece with more evaluation etc. in around a week. No point is posting something that turns out to be wrong.
That’s good enough for Osborn’s fellow alarmists. Michael Mann replies:
great–thanks Tim, sounds like we have a plan. in our post, which we’ll target for tomorrow as well, we’ll simply link to whatever CRU puts up and re-iterate the sentiment of the temporary short response (i.e. that there was no cherry-picking, a careful and defensible selection procedure was used) and we’ll mostly focus on the broader issues, i.e. that any impact of this one series in the vast array of paleoclimate reconstructions (and the importance of the paleoclimate reconstructions themselves) has been over-stated, why these sorts of attacks are not legitimate science, etc.
Note that the alarmists are willing to denounce McIntyre’s work as “not legitimate science” even though, at this point, they still have no idea whether his analysis was right or wrong. That is not, however, what they tell the outside world. On September 29, Andrew Revkin, environmental reporter for the New York Times, wrote to Mann asking about McIntyre’s critique:
needless to say, seems the 2008 pnas paper showing that without tree rings still solid picture of unusual recent warmth, but McIntyre is getting wide play for his statements about Yamal data-set selectivity.
Has he communicated directly to you on this and/or is there any indication he’s seeking journal publication for his deconstruct?
Mann, ignorant of the facts, responds by slandering McIntyre:
Hi Andy, I’m fairly certain Keith is out of contact right now recovering from an operation, and is not in a position to respond to these attacks. However, the preliminary information I have from others familiar with these data is that the attacks are bogus.
It is unclear that this particular series was used in any of our reconstructions (some of the underlying chronologies may be the same, but I’m fairly certain the versions of these data we have used are based on a different composite and standardization method), let alone any of the dozen other reconstructions of Northern Hemisphere mean temperature shown in the most recent IPCC report, which come to the conclusion that recent warming is anomalous in a long-term context.
So, even if there were a problem w/ these data, it wouldn’t matter as far as the key conclusions regarding past warmth are concerned. But I don’t think there is any problem with these data, rather it appears that McIntyre has greatly distorted the actual information content of these data.
Given what is said in the other emails, that last attack on McIntyre appears to be simply fabricated out of whole cloth. Mann concludes by buttering up Revkin:
Fortunately, the prestige press doesn’t fall for this sort of stuff, right?
Of course not! Revkin replies, “Thanks heaps.”
At the same time they were issuing these assurances to outsiders, however, the alarmists’ internal communications were much more equivocal. On September 30, the day after he corresponded with Revkin, Mann asked Tim Osborn to confirm that a key 2006 paper co-authored by Osborn and Briffa was untainted by what is implicitly acknowledged to be Briffa’s bad Yamal data:
And Osborn and Briffa ’06 is also immune to this issue, as it eliminated any combination of up to 3 of the proxies and showed the result was essentially the same (fair to say this Tim?).
Osborn’s reply is hedged at best, and includes a rather insouciant admission that he is “amazed” that the journal Science agreed to publish his paper in the first place:
yes, you’re right: figs S4-S6 in our supplementary information do indeed show results leaving out individual, groups of two, and groups of three proxies, respectively. It’s attached.
I wouldn’t say we were immune to the issue — results are similar for these leave 1, 2 or 3 out cases, but they certainly are not as strong as the case with all 14 proxies.
Certainly in figure S6, there are some cases with 3 omitted (i.e. some sets of 11) where modern results are comparable with intermittent periods between 800 and 1100. Plus there is the additional uncertainty, discussed on the final page of the supplementary information, associated with linking the proxy records to real temperatures (remember we have no formal calibration, we’re just counting proxies — I’m still amazed that Science agreed to publish something where the main analysis only involves counting from 1 to 14!
But this is fine, since the IPCC AR4 and other assessments are not saying the evidence is 100% conclusive (or even 90% conclusive) but just “likely” that modern is warmer than M[edieval] W[arm] P[eriod]. …
So, this Yamal thing doesn’t damage Osborn & Briffa (2006), but important to note that O&B (2006) and others support the “likely” statement rather than being conclusive.
Another member of the climate alarmist cabal, Tom Wigley, gave this darker assessment of Briffa’s errors with regard to the tree ring data on October 5. Note in particular his concern about the alarmists’ practice of withholding data from public review:
It is distressing to read that American Stinker item. But Keith does seem to have got himself into a mess. As I pointed out in emails, Yamal is insignificant. And you say that (contrary to what M&M say) Yamal is *not* used in MBH, etc. …
But, more generally, (even if it *is* irrelevant) how does Keith explain the McIntyre plot that compares Yamal-12 with Yamal-all? And how does he explain the apparent “selection” of the less well-replicated chronology rather that the later (better replicated) chronology?
Of course, I don’t know how often Yamal-12 has really been used in recent, post-1995, work. I suspect from what you say it is much less often that M&M say — but where did they get their information? I presume they went thru papers to see if Yamal was cited, a pretty foolproof method if you ask me. Perhaps these things can be explained clearly and concisely — but I am not sure Keith is able to do this as he is too close to the issue and probably quite pissed of[f].
And the issue of with-holding data is still a hot potato, one that affects both you and Keith (and Mann). Yes, there are reasons — but many *good* scientists appear to be unsympathetic to these. The trouble here is that with-holding data looks like hiding something, and hiding means (in some eyes) that it is bogus science that is being hidden.
I think Keith needs to be very, very careful in how he handles this. I’d be willing to check over anything he puts together.
This strikes me as a damning commentary on the entire alarmist enterprise. Meanwhile, not only are Briffa’s data flawed and seemingly cherry-picked, the assumptions on which the tree-ring studies are based may be bogus in the first place. The email collection includes these two messages from a plant scientist, both within the last 60 days:
Dear Professor Briffa, my apologies for contacting you directly, particularly since I hear that you are unwell. However the recent release of tree ring data by CRU has prompted much discussion and indeed disquiet about the methodology and conclusions of a number of key papers by you and co-workers.
As an environmental plant physiologist, I have followed the long debate starting with Mann et al (1998) and through to Kaufman et al (2009). As time has progressed I have found myself more concerned with the whole scientific basis of dendroclimatology. In particular;
1) The appropriateness of the statistical analyses employed
2) The reliance on the same small datasets in these multiple studies
3) The concept of “teleconnection” by which certain trees respond to the “Global Temperature Field”, rather than local climate
4) The assumption that tree ring width and density are related to temperature in a linear manner.
Whilst I would not describe myself as an expert statistician, I do use inferential statistics routinely for both research and teaching and find difficulty in understanding the statistical rationale in these papers. As a plant physiologist I can say without hesitation that points 3 and 4 do not agree with the accepted science.
There is a saying that “extraordinary claims require extraordinary proof”. Given the scientific, political and economic importance of these papers, further detailed explanation is urgently required.
Dr. Don Keiller.
Tree ring studies are vitally important to the conclusions reached by the U.N.’s IPCC report, which is the main foundation for the claim that anthropogenic global warming has been “proved.” That being the case, one would think that Briffa, one of the two or three primary authors of the tree ring studies, would have a ready response to these very basic questions. But no: he did not reply to Dr. Keiller’s email. That prompted this second inquiry from Dr. Keiller:
Dear Professor Briffa, I am pleased to hear that you appear to have recovered from your recent illness sufficiently to post a response to the controversy surrounding the use of the Yamal chronology; (http://www.cru.uea.ac.uk/cru/people/briffa/yamal2009/cautious/cautious.htm) and the chronology itself; (http://www.cru.uea.ac.uk/cru/people/briffa/yamal2009/)
Unfortunately I find your explanations lacking in scientific rigour and I am more inclined to believe the analysis of McIntyre (http://www.climateaudit.org/?p=7588) Can I have a straightforward answer to the following questions
1) Are the reconstructions sensitive to the removal of either the Yamal data and Strip pine bristlecones, either when present singly or in combination?
2) Why these series, when incorporated with white noise as a background, can still produce a Hockey-Stick shaped graph if they have, as you suggest, a low individual weighting?
And once you have done this, please do me the courtesy of answering my initial email.
Dr. D.R. Keiller
Again, one might assume that if the science surrounding global warming is settled, the alarmists would have good answers to such basic questions, and certainly would be willing to engage in debate in a spirit of open-minded inquiry. Such, however, is not the case. Phil Jones of East Anglia advised Briffa against trying to respond to the plant scientist on October 20:
There is a lot more there on CA now. [I’m pretty sure CA is Climate Audit, a web site where McIntyre posts.] I would be very wary about responding to this person now having seen what McIntyre has put up.
You and Tim talked about Yamal. Why have the bristlecones come in now. http://www.climateaudit.org/?p=7588#comments
This is what happens – they just keep moving the goalposts. Maybe get Tim to redo OB2006 without a few more series.
As far as I can tell from the email archive, Briffa never did respond to the plant scientist. Jones’s email warning Briffa to be “very wary about responding to this person now having seen what McIntyre has put up” was written just three weeks ago. It, along with the rest of the email archive, makes an utter mockery of the alarmists’ claim that the science of global warming is settled in their favor.
On the contrary, the conclusion an observer is likely to draw from the CRU archive is that the climate alarmists are making up the science as they go along and are fitting facts to reach a predetermined conclusion rather than objectively seeking after truth. What they are doing is politics, not science. When I was in law school, this story was told about accountants: A CEO is going to hire a new accountant and summons a series of candidates. He asks each applicant, “What is two plus two?” The first two candidates answer, “Four.” They don’t get the job. The third responds, “What do you want it to be?” He gets hired. The climate alarmists’ attitude toward data appears to me much the same as that fictional accountant’s attitude toward arithmetic.
UPDATE: More here and here.