Guest Post by Willis Eschenbach
The official report of the Pennsylvania State University Inquiry Committee into the actions of Dr. Michael Mann is available here. It is the Report of the Inquiry that Mann says exonerated him completely of the three most important allegations.
From Cartoons by Josh
The Inquiry Report was written by professors. As you might expect, it has plenty of extra words and paragraphs. So let’s take a tour through just the highlights of the Inquiry Report.
The quotations in bold italics are from the report. Nothing is taken out-of-order, and I have endeavored to include sufficient context. Here’s where the story started:
Beginning on and about November 22, 2009, The Pennsylvania State University began to receive numerous communications (emails, phone calls and letters) accusing Dr. Michael E. Mann of having engaged in acts that included manipulating data, destroying records and colluding to hamper the progress of scientific discourse around the issue of anthropogenic global warming from approximately 1998. These accusations were based on perceptions of the content of the widely reported theft of emails from a server at the Climatic Research Unit of the University of East Anglia in Great Britain.
Given the sheer volume of the communications to Penn State, the similarity of their content and their sources, which included University alumni, federal and state politicians, and others, many of whom had had no relationship with Penn State, it was concluded that the matter required examination by the cognizant University official, namely Dr. Eva J. Pell, then Senior Vice President for Research and Dean of the Graduate School. The reason for having Dr. Pell examine the matter was that the accusations, when placed in an academic context, could be construed as allegations of research misconduct, which would constitute a violation of Penn State policy.
A fine start. Numerous people are calling for an investigation, so Penn State will look to see if one is justified. They go on to cite the relevant policy statements that Mann may or may not have violated:
Under The Pennsylvania State University’s policy, Research Administration Policy No. 10, (hereafter referred to as RA-10), Research Misconduct is defined as:
(1) fabrication, falsification, plagiarism or other practices that seriously deviate from accepted practices within the academic community for proposing, conducting, or reporting research or other scholarly activities;
(2) callous disregard for requirements that ensure the protection of researchers, human participants, or the public; or for ensuring the welfare of laboratory animals;
(3) failure to disclose significant financial and business interest as defined by Penn State Policy RA20, Individual Conflict of Interest;
(4) failure to comply with other applicable legal requirements governing research or other scholarly activities.
RA-10 further provides that “research misconduct does not include disputes regarding honest error or honest differences in interpretations or judgments of data, and is not intended to resolve bona fide scientific disagreement or debate.”
That seems quite clear. Then they look at the “purloined emails” (love the term they use) and discuss what they plan to investigate:
From November 30 to December 14, 2009, staff in the Office for Research Protections culled through approximately 1075 of the emails that were purloined from a server at the University of East Anglia. Emails were reviewed if they were sent by Dr. Mann, were sent to Dr. Mann, were copied to Dr. Mann, or discussed Dr. Mann (but were neither addressed nor copied to him). In summary, the following were found:
• 206 emails that contained a message/text from Dr. Mann somewhere in the chain;
• 92 emails that were received by Dr. Mann, but in which he did not write/participate in the discussion; and
• 79 that dealt with Dr. Mann, his work or publications; he neither authored nor was he copied on any of these.
From among these 377 emails, the inquiry committee focused on 47 emails that were deemed relevant. On December 17, 2009, the inquiry committee (Pell, Scaroni, Yekel), Dr. Brune and Dr. Foley met to review the emails, discuss the RA-10 inquiry process and go over what their respective activities would be. It was agreed that these individuals would meet again in early January and that they would use the time until that meeting to review the relevant information, including the above mentioned e-mails, journal articles, OP-ED columns, newspaper and magazine articles, the National Academy of Sciences report entitled “Surface Temperature Reconstructions for the Last 2,000 Years,” ISBN: 0-309-66144-7 and various blogs on the internet.
Well, that all sounds impressive, until you finish reading the entire report. At that point you realize that the paragraph above is the last you hear of any of this stuff. None of the important questions are ever answered. Which 47 emails were deemed to be relevant, and why? What was learned from the 47 relevant emails? Which “blogs on the internet” did they review, and what were the results? Which OP-ED columns did they read, and what did they conclude? We never find out anything further. The rest of the report is silent on everything listed in that section.
So it is just handwaving about the emails, presenting lots of numbers and no content. They also list all those things that they are supposedly going to look into, newpapers and journal articles … and then they never refer to any of that again. Without details, that is just filler, hollow claims without a stitch of followup or substantiation. Meaningless. We don’t even know if they understood the import of the emails, or which ones they found important. Nothing.
Back to the report. Next they discuss who would make up the inquiry team, followed by this explanation of how they defined the allegations against Dr. Mann:
At the time of initiation of the inquiry, and in the ensuing days during the inquiry, no formal allegations accusing Dr. Mann of research misconduct were submitted to any University official. As a result, the emails and other communications were reviewed by Dr. Pell and from these she synthesized the following four formal allegations. To be clear, these were not allegations that Dr. Pell put forth, or leveled against Dr. Mann, but rather were her best effort to reduce to allegation form the many different accusations that were received from parties outside of the University. The four synthesized allegations were as follows:
1. Did you engage in, or participate in, directly or indirectly, any actions with the intent to suppress or falsify data?
2. Did you engage in, or participate in, directly or indirectly, any actions with the intent to delete, conceal or otherwise destroy emails, information and/or data, related to AR4, as suggested by Phil Jones?
3. Did you engage in, or participate in, directly or indirectly, any misuse of privileged or confidential information available to you in your capacity as an academic scholar?
4. Did you engage in, or participate in, directly or indirectly, any actions that seriously deviated from accepted practices within the academic community for proposing, conducting, or reporting research or other scholarly activities?
I was surprised by the vague, broad, and unspecified nature of these allegations. If they actually had read and understood the purloined CRU emails, I would have thought that they would have identified the specific instances of things in the emails that looked shonky. But at least they cover the ground.
After further procedural matters, they report how they decided on what exact questions to ask Dr. Mann:
… it was decided that each committee member would send Dr. Foley specific questions that would be added to the four formal allegations and that would be used by the committee during the interview of Dr. Mann. These were compiled into one document. It was also decided that during the upcoming interview of Dr. Mann, Dr. Foley would ask each of the initial questions with follow up questions coming from the other committee members, and he would moderate the interview.
That is followed by their report of the first actual piece of investigation, their interview with Dr. Mann. They report on this interview as follows:
In an interview lasting nearly two hours, Dr. Mann addressed each of the questions and follow up questions. A recording was made of the meeting, and this recording was transcribed. The committee members asked occasional follow-up questions. Throughout the interview, Dr. Mann answered each question carefully:
• He explained the content and meaning of the emails about which we inquired;
• He explained that he had never falsified any data, nor had he had ever manipulated data to serve a given predetermined outcome;
• He explained that he never used inappropriate influence in reviewing papers by other scientists who disagreed with the conclusions of his science;
• He explained that he never deleted emails at the behest of any other scientist, specifically including Dr. Phil Jones, and that he never withheld data with the intention of obstructing science; and
• He explained that he never engaged in activities or behaviors that were inconsistent with accepted academic practices.
OK. They met with Mann for two hours, what I would see as a preliminary interview to get his claims on the record so they could be checked. He told them he was totally, completely innocent and as pure as new driven snow. The interview was recorded and transcribed.
So far, the inquiry was going very, very predictably, basic stuff. First Step. Initial Interview With Subject. Subject denies everything. Interview recorded, transcribed, and done. Check the first box on the checklist.
But at that point, things take an astounding turn. Here is the very next event in the chronology, as described in the very next paragraphs of the Report.
On January 15, 2010, and on behalf of the inquiry committee, Dr. Foley conveyed via email an additional request of Dr. Mann, who was asked to produce all emails related to the fourth IPCC report (“AR4”), the same emails that Dr. Phil Jones had suggested that he delete.
On January 18, 2010, Dr. Mann provided a zip-archive of these emails and an explanation of their content. In addition, Dr. Mann provided a ten page supplemental written response to the matters discussed during his interview.
They asked him to provide them emails? They asked him to assemble and send them the evidence against himself?
He works for Penn State. The ownership of the emails is theirs. They are investigating him. The very, very first thing that is done in an investigation of this sort is to do an email dump of the subject of the investigation. Then the investigators go through to see what they can find.
THEY ASKED MANN TO ASSEMBLE THE EMAIL EVIDENCE AGAINST HIMSELF!!! I know I’m shouting and that’s impolite, but it needs to be shouted. If any one thing about this Inquiry characterizes the bumbling incompetence of the Inquirers, surely it is that single fact — that they let him pick and choose the evidence to be used against him. I mean, you could stop right there and go home knowing all you need to know about the quality and impartiality of the Inquiry.
But as tempting as going home might be at this point, the report continues, and so perforce we also must continue along the weary trail of their tortured caricature of an inquiry. However, as we proceed, remember that they asked him to assemble the evidence against himself. I’d heard stories that professors were out of touch with the real world, but c’mon, folks, don’t professors watch cop shows once in a while? That’s bozo level Investigation 101. Do an email dump of his machine and the email server, then compare the emails that were deleted from his computer to the emails that remain in the server.
But nooooo, he’s their esteemed colleague, that would be unseemly, so they politely asked him to send them the email evidence showing whether he had deleted emails or done anything else underhanded … words fail me.
After their killer hard-hitting look at the email question, and their collegiate discussion with their esteemed colleague, what did they look into next? The Penn State clown car careens on to the next step in their relentless inquiry, as shown by the next paragraph:
On January 22, 2010, the inquiry committee and Dr. Brune met again to review the evidence, including but not limited to Dr. Mann’s answers to the committee’s questions, both in the interview and in his subsequent submissions. All were impressed by Dr. Mann’s composure and his forthright responses to all of the queries that were asked of him. At this point, Dr. Foley reviewed the relevant points of his conversation with Dr. Gerald North, a professor at Texas A&M University and the first author of the NAS’ 2006 report on Dr. Mann’s research on paleoclimatology. Dr. Foley also relayed the sentiment and view of Dr. Donald Kennedy of Stanford University and the former editor of Science Magazine about the controversy currently swirling around Dr. Mann and some of his colleagues. Both were very supportive of Dr. Mann and of the credibility of his science.
Just kidding about the relentless inquiry, that was it. Four days after getting the emails from Mann, the party was over. At that point, looking for evidence was passé. All relevant questions had been asked. They were finished with the inquiry part, no more evidence collection, that was it, time to examine the collected evidence.
The above paragraph says that with the inquiry safely behind them and all relevant evidence gathered, they met to consider that evidence. Bear in mind that the totality of the evidence that they report being collected by their inquiry was:
1. Mann denied everything, and they were impressed with his style.
2. Two friends of Mann told Dr. Foley that they were supportive of Mann.
3. None of the emails chosen by Mann showed any evidence of wrongdoing.
Based on that evidence, four days later, on January 26, 2010, the inquiry committee met to announce their findings.
After a careful review of all written material, and information obtained from the purloined emails, the interview of Dr. Mann, the supplemental materials provided by Dr. Mann and all the information from other sources, the committee found as follows with respect to each allegation:
OK, moment of truth, drum roll, please …
Regarding the first charge, ladies and gentlemen of the Jury, did Dr. Mann engage in, or participate in, directly or indirectly, any actions with the intent to suppress or falsify data? How does the Penn State Jury find?
As there is no substance to this allegation, there is no basis for further examination of this allegation in the context of an investigation in the second phase of RA-10.
So take that, you callous unbelievers, there’s no need for any kind of further investigation. Case closed, total exoneration. And further …
The so-called “trick” was nothing more than a statistical method used to bring two or more different kinds of data sets together in a legitimate fashion by a technique that has been reviewed by a broad array of peers in the field.
Nonsense. The “trick” is a way to hide adverse data, something that scientists should never do. At least they have proven conclusively that the inquiry committee members were neither statisticians nor mathematicians. And that they weren’t investigators either, or even inquirers. But I digress …
Regarding the second allegation, did Dr. Mann engage in, or participate in, directly or indirectly, any actions with the intent to delete, conceal or otherwise destroy emails, information and/or data, related to AR4, as suggested by Phil Jones, how does the Jury find?
As there is no substance to this allegation, there is no basis for further examination of this allegation in the context of an investigation in the second phase of RA-10.
The emails Mike provided showed no wrongdoing regarding AR4, so again no investigation is necessary … I’m not sure how they got around the CRU email where Mann told Jones that he would pass Jones’s request to (illegally) delete any AR4 emails on to Gene Wahl. That one is real hard to peanut butter over, but somehow they did it.
Maybe that email wasn’t one of the 47 relevant emails. Or maybe it was, but they just identified the 47 relevant emails and never asked Mann about them … we don’t know.
In any case, regarding the third allegation, did Dr. Mann engage in, or participate in, directly or indirectly, any misuse of privileged or confidential information available to him in his capacity as an academic scholar, how does the Jury find:
As there is no substance to this allegation, there is no basis for further examination of this allegation in the context of an investigation in the second phase of RA-10.
Same same, no investigation needed, everything is for the best in this the best of all possible worlds for the first three inquiries.
And as to the final allegation, did Dr. Mann engage in, or participate in, directly or indirectly, any actions that seriously deviated from accepted practices within the academic community for proposing, conducting, or reporting research or other scholarly activities, how does the Jury find?
The Jury finds nothing!
Fooled you, huh, and it fooled me too. But then I remembered that these are university professors. They know the rules. And it’s against the rules to deal conclusively with every single item on any given agenda. For at least one item, you are required to form a new committee to further investigate the matter. And true to their code, they decided Allegation Four was just too tough to answer. So they closed their report by punting the ball to a new committee. This is a committee to do an investigation into allegation four …
And that was it, folks. That was the inquiry that Mann says “exonerated” him of any wrongdoing on the first three allegations of misconduct. The inquiry that decided that there was no need for an investigation on the three most important allegations, case closed.
But wait, it gets worse. You remember that the Report said the interview with Mann was recorded and transcribed? Perhaps it got misplaced or something, because it hasn’t been released. So the Inquirers haven’t bothered to let us know what questions Mann was asked, or what his answers were.
But at least the Inquirers have been good enough to tell us the crucial information, that they were impressed by Dr. Mann’s composure and his forthright responses …
Me, I’m sitting here at my keyboard and busting out laughing at this pitiable grade-school excuse for an inquiry. I mean, it’s the perfect storm of inquiries. Ask Mann if he’s innocent, ask him if he’s got any incriminating emails, talk to two of his friends, collect a bit of unspecified information from unknown “sources”, and then deny the need for any further investigation, based on the lack of evidence of wrongdoing … that’s delicious. They studiously avoid collecting any evidence, so studiously that they don’t talk to a single critic of Mann’s actions.
And then they say that there isn’t enough evidence to justify an investigation, and they decline to show us any of the evidence! Man, that is as sweet a scam as I can imagine, right up there with Catch-22.
In a bizarre way, the outcome of this Inquiry is custom made for Michael Mann. Here’s why. You remember that for years we couldn’t tell if Mann had done anything wrong with the Hockeystick, because the data wasn’t released?
Well, to close the circle, now we can’t tell if Mann was forthright with the Inquiry Committee, or even what he questions he was asked, because the data wasn’t released.
Perfect symmetry.
Penn State Alumni, where is the outrage? Might be out there and I missed it, but roar, Nittany Lions, roar!
OTHER VOICES
Steve McIntyre has interesting analyses here and here. In the latter he highlights issues arising from the fact that this was an inquiry into whether enough evidence exists to justify an investigation, and not the subsequent investigation itself.
This was an inquiry, for which you would expect lower standards of proof. All you need is enough facts to justify an investigation. Now me, at that lower standard I thought the Climategate emails were prima facie evidence that an investigation was warranted, not some pissant inquiry. But despite their dedicated and exhaustive searches for evidence, the dedicated Inquirers couldn’t even satisfy that lower inquiry standard and ask for an investigation … ah, well.
Steve also discusses Cuccinelli here.
Steve Milloy raises addition questions here.
Fox News weighs in from the right.
Bishop Hill adds to the story here.
Lucia hosts a discussion at the Blackboard.
The Report of the final Investigation into the part of the Inquiry that couldn’t be decided by the previous Inquiry is here. The Investigation into the fourth allegation of the Inquiry report says there was nothing to see here, move along. I know you are surprised by that news.
Jeremy: “Seismology, for instance, doesn’t go out presenting their best understanding of earthquake prediction to secure tons of extra funding because they feel they could predict the next big earthquake with more funding.”
I’m not talking about funding, rather the comunication of the science, and I am sure that seismologists simplify the science when they’re talking to the public.
“Phil Jones has also said (Jones & Mann 2004):
“…Our assessment affirms the conclusion that late 20th century warmth is unprecedented at hemispheric and, likely, global scales.”
It’s hard to imagine that the man is being taken completely wrong by the public based on such comments.”
I’m not familiar with the context of this quote, but I don’t see the relevance to my claim that “not statistically significant” is misinterpreted as “no significant warming” or “no warming”.
Willis Eschenbach: “The post-1960 data doesn’t fit the theory. Which makes the theory (at least for those particular tree rings) very doubtful.”
Possibly, although not necessarily. It would depend on the weight of other evidence. What we know is that the proxies diverge from the measured temperatures. That’s a puzzle, which may cast doubt on the theory or may have an explanation that is consistent with the theory. But we don’t know enough yet to make a definitive judgement.
“You see, if we know the tree ring widths don’t fit the temperature post-1960, there is absolutely no reason to assume they will do so pre-1860…”
That would depend on other available evidence. As for “hiding the decline”, if the method is understood and accepted as legitimate among scientists I don’t see a problem.
This isue also highlights some of the problems in science communication, since science is often hedged with caveats and uncertainties that the public can find unsatisfactory.
@ur momisugly Luke Warneminde:
I will re-clarify my point more carefully this time:
Tree growth measurements before 1960 does agree with direct temperature measurements and is an accurate proxy for temperature.
Tree growth measurements after 1960 does not agree with direct temperature measurements and is not an accurate proxy for temperature.
“Tree rings are a critically important proxy for reconstructing the high resolution climate of the past millennium and are the dominant data type in most large scale hemispheric reconstructions [e.g. Mann et al., 1999; Esper et al., 2002; D’Arrigo et al., 2006]. The statistical calibration and verification of tree-ring based reconstructions have made the science of dendrochronology perhaps the most rigorous of those available in this regard. Such records are invaluable for placing recent climatic changes in a long-term context, which can aid considerably in the detection of anthropogenic change.” (D’Arrigo et al., 2007, pg. 1-2)
“The divergence problem has important consequences for the utilization of tree-ring records from temperature-limited boreal sites in hemispheric-scale proxy temperature reconstructions (Jones et al., 1998; Mann et al., 1999; Briffa, 2000; Briffa et al., 2001; Esper et al., 2002; Cook et al., 2004a; Moberg et al., 2005; D’Arrigo et al., 2006; Hegerl et al., 2006). The principal difficulty is that the divergence disallows the direct calibration of tree growth indices with instrumental temperature data over recent decades (the period of greatest warmth over the last 150 years), impeding the use of such data in climatic reconstructions.” (D’Arrigo et al., 2007, pg. 8)
“The inability of many reconstruction models to verify in the recent period has compelled a number of researchers to eliminate recent decades from their calibration modeling, effectively shortening the available periods for direct calibration and verification testing between tree rings and climate (e.g., Briffa et al., 2001; Cook et al., 2004a; Rutherford et al., 2005; D’Arrigo et al., 2006). (D’Arrigo et al., 2007, pg. 8)
“Other important issues to consider in evaluating the divergence problem are whether or not this phenomenon is unprecedented over the past millennium, and to what extent it is spatially constrained to northern latitude (boreal) forests. A recent analysis by Cook et al. (2004a) suggests that the divergence is restricted to the recent period and is unique over the past thousand years. It is thus likely to be anthropogenic in origin.” (D’Arrigo et al., 2007, pg. 10)
I have shared with you here a selection of relevant quotes from D’Arrigo, R. et al. On the ‘Divergence Problem’ in Northern Forests: A review of the tree-ring evidence and possible causes. Glob. Planet. Change (2007), doi:10.1016/j.gloplacha.2007.03.004 which I believe explain my points stronger than I can myself.
The recent divergence problem, although caused by a number of complex factors, appears to be unique to the last 50 years and paleoclimatologists remain confident in the accuracy of the reconstructions of temperatures between the 1500s and 1960s.
I meant to have included a link to the D’Arrigo et al. paper:
http://www.ldeo.columbia.edu/~liepert/pdf/DArrigo_etal.pdf
Simplifying the science does not mean presenting a selectively-distilled version of the truth. Seismologists reporting to the local media in Southern California generally start off all post-earthquake reporting with “of course it is impossible to predict earthquakes.” It is almost always this way. Climate scientists seem to start off with quotes like the one I gave you for Phil Jones, “We have 9x% percent confidence that mans activities will lead to catastrophe.” I’m surprised the difference isn’t obvious, and I’m surprised anyone feels like it is impossible to present scientific truth in its full state to the general public. Frankly I can’t think of a better way to insult humanity in general.
If I’m reading you right, your claim centered around Phil Jones’ statement being watered down to become Phil Jones saying that there has been no warming. I presented an example of Phil Jones spouting non-caveated “scientific truth” on the matter.
To my mind, any scientist who is willing to go on public record as saying things without qualification and explanation of assumptions puts him/herself on the chopping block for precisely what your example demonstrates. If you are a scientist and the public calls on you to report to them, you must present the whole truth all of the time, or expect to become a political football that gets kicked around.
Thank you for sharing. If these quotes “explain my points stronger than I can myself” then all you seem to be saying is that you choose to believe a line of argument that many people find flawed. The apparent flaws have been stated repeatedly in this thread.
The only glimmer of hope for your position would seem to be “the recent analysis by Cook et al. (2004a) [which] suggests that the divergence is restricted to the recent period and is unique over the past thousand years.” Perhaps you could explain why anyone would believe the divergence to be unique (and possibly anthropogenic)?
Jeremy: “Simplifying the science does not mean presenting a selectively-distilled version of the truth.”
I didn’t say that it did. You wanted the data to be “displayed wholly naked and dirty”. I was pointing out that communicating science is not easy, and is subject to misrepresentation, especially when people take a pre-determined position through which they view scientific statements.
“Climate scientists seem to start off with quotes like the one I gave you for Phil Jones….”
As I say, I’m not familiar with the context of that quote, but here are couple by a scientist who speaks on climate matters:
“Global Warming, as we think we know it, doesn’t exist.”
“This in fact is the greatest deception in the history of science.”
Not many caveats there.
http://www.canadafreepress.com/2007/global-warming020507.htm
“If I’m reading you right, your claim centered around Phil Jones’ statement being watered down to become Phil Jones saying that there has been no warming.”
You were reading me right, although I wouldn’t say that the quote was “watered down” so much as distorted.
My example demonstrates that where a scientist expresses caveats, there will always be people who will take advantage to distort the message. In those cases, the scientist is not at fault, in fact is in a no-win situation.
If he presents all the caveats and nuances, he risks losing the audience and/or a distortion of the message. If he simplifies the message, he risks being accused of not presenting the “whole truth”.
Brendan H says:
October 20, 2010 at 11:21 pm
Oh, please, that’s wishy-washy handwaving. Although we don’t have enough evidence to make a definitive judgement, we certainly know that at this point the theory (that we can trust the tree rings to be accurate about temperature in say 1533) is wrong. We don’t know why it is wrong, so you are right, we can’t make a definitive judgement.
But we can say that until we do understand what is going on, we cannot trust that proxy. And we certainly do not have the slightest scientific evidence to say it is valid to just cut out the part that doesn’t agree with the theory.
@ur momisugly Frank:
First, the correlation between tree growth and temperature between 1880 and 1960 is strong enough to be more than a coincidence. Also, the mechanism for how temperature affects tree growth is well understood. The combination of strong correlation and solid explanation is sufficient for attributing temperature as a major factor of tree growth between 1880 and 1960.
Second, the divergence effect is not a universal effect. It seems to be more regionally applicable to circumpolar forest growth than to more southern forest growth. This implies that a regional or local factor is causing the divergence effect, rather than the failure of a global factor such as temperature.
Third, the tree growth reconstructions of temperature have a strong correlation with other independent reconstructions of temperature such as those from ice bore holes, coral, glacier length, etc. This correlation with other independent reconstructions adds significantly to the confidence of its accuracy.
Are there any good reasons why tree growth reconstructions are unreliable? Peer-reviewed climate science doesn’t seem to think so. Why not?
Willis Eschenbach: “Although we don’t have enough evidence to make a definitive judgement, we certainly know that at this point the theory (that we can trust the tree rings to be accurate about temperature in say 1533) is wrong.”
Your claim, “is wrong”, certainly sounds like a definitive judgement. But to use your own reasoning, if we don’t have enough evidence to make a definitive judgement, then there’s no justification for making a definitive judgement.
“And we certainly do not have the slightest scientific evidence to say it is valid to just cut out the part that doesn’t agree with the theory.”
Sounds like another definitive judgement. When you say that “we certainly do not have the slightest scientific evidence” for omitting part of the proxy record, are you saying that scientists have offered no arguments or reasons for treating the record in this way?
Or do you mean that you are not convinced by the arguments and reasons offered by climate scientists?
“Are there any good reasons why tree growth reconstructions are unreliable?”
There are as yet unexplained divergences from thermometer data!
“Peer-reviewed climate science doesn’t seem to think so. Why not?”
They have a lot invested in the orthodoxy of manmade global warming.
(BTW can we move away from this fetish about peer-review? It is merely a sign that published work is, as far as a few people selected by journal editors can see, plausible, NOT that it is correct. As far as the data are concerned that requires replication. As for the interpretation, that requires that no-one comes up with alternatives that fit the data and even then acceptance will always remain provisional.
@ur momisugly Dan:
Temperature reconstructions from tree growth data after 1960 do not correlate well with direct temperature records. There is evidence of this being caused by a complex combination of local and global factors, such as global dimming caused by aerosols and increased drought.
Temperature reconstructions from tree growth data before 1960 correlate very well with not only direct temperature records between 1880 and 1960, but also with other, independent temperature reconstructions (from proxies such as ice bore holes, glacial length, etc.).
There is no evidence that the factors that are appear to be causing the post-1960 divergence effect had much of an effect before 1960. There is no evidence that this divergence effect is not unique to the last 50 years. There is some evidence, however, that the factors causing this divergence effect are unique to the last 50 years.
The correlation of pre-1960s tree growth to direct temperature records and other reconstructions is too strong to be coincidental.
Sorry, Matt, that’s wrong. Tree growth correlates much more closely to rising CO2 than to temperature, as these thirty peer reviewed studies show. I have more studies if you’re interested. Just ask.
“Hide the decline” was a devious attempt to hide that discrepancy, and Mann’s apologists have been scrambling to make up excuses for his shenanigans ever since he was caught playing his tree ring games.
Brendan H says:
October 22, 2010 at 2:33 am
My apologies for my lack of clarity. There are two different judgements involved.
There is no final word on whether or not the pre-divergence part of the tree ring records are a valid proxy or not. No definitive judgement. We simply don’t have any evidence.
However, the fact that the post-divergence records are not a valid proxy for temperature means that the tree ring records as a whole are not a valid proxy for temperature. And because of that, at present we we have no reason to trust the pre-divergence records.
We may get to that point, we may someday be able to explain the divergence problem. We may get a definitive judgement on the question someday.
But right now, we can make a very different definitive judgement, which agrees with many other people who have studied the question. The judgement is that at present, we should avoid using those proxies in reconstructions.
There is an associated problem. Since the divergence occurs during the calibration/validation period of the observational record, the divergence means that we cannot calibrate and validate the proxy … so yes, we can make a definitively judgement at this point that we should not use these proxies until we understand them.
@ur momisugly Jeremy:
The justification of truncation arises when it is unjustifiable to reconstruct temperature from data which does not track temperature accurately enough. The climate science community has generally agreed that it is unjustifiable to reconstruct temperature from post-1960 tree growth data due to the divergence effect.
People are not just ignoring the divergence effect, though. Precisely because it casts some doubt on our understanding of tree growth, significant research is being focused on understanding this effect.
On the question of caveats, the intended reader of science literature is not the average citizen, but instead somebody knowledgeable about the topic they are reading. When discussing tree growth reconstructions, the divergence effect is regularly discussed. Does there need to be a bold warning for readers saying “THE SCIENTIFIC UNDERSTANDING ON THIS TOPIC IS NOT YET COMPLETE”? It is precisely because the scientific understanding is incomplete that there is scientific literature. It is unreasonable to expect somebody to wait until certainty to present scientific research, because that day will never come. Tree growth reconstruction literature works the same way: the divergence effect is discussed as a problem in our understanding that needs to be solved, but does not invalidate the entire collection of research and data.
@ur momisugly Jeremy:
Concerning “deleting data” and “truncating a reconstruction”, there is a significant difference between the two. “Deleting data” involves hiding something which you don’t want to be found. “Truncating a reconstruction” involves maintaining a high standard of reliability of the data used. The divergence effect hasn’t been “hidden” by climate scientists in order to deceptively boost public confidence in climate reconstructions. Instead, there has been a large amount of scientific focus on understanding and explaining the divergence effect. Explaining the divergence effect to the lay public is not a high priority for climate scientists because they shouldn’t have to.
The climate science community has reached conclusions for immediate action and have published their extensive reasoning in decades of scientific literature. Due to the nature of paradigmatic science, scientists will never claim that they are 100% confident in their results, but to dismiss decades of scientific reasoning with a handful of claims like “That’s a big scientific no-no!” is completely unreasonable.
As for what you wrote about the data being “dressed up in the best new suit the emperor could buy”, that is precisely what a metaphor is. You are describing the data being figuratively dressed up in a suit. To insist that the data was literally dressed up in a suit is ridiculous. You did use a metaphor. That is not what “actually happened”.
Furthermore, your metaphor is slightly confusing. With your use of the phrases “displayed wholly naked and dirty in the streets” and “the best new suit the emperor could buy”, you seem to be alluding to the fable of the emperor’s new clothes, where the emperor is tricked into walking down the streets naked, thinking he is wearing an expensive, invisible set of clothes. Your invocation of this fable was probably unintentional, but if not, I’m confused about what you are implying.
@ur momisugly PhilJourdan:
The increasing accuracy of temperature measurements does not invalidate previous temperature measurements. An accurate global trend of temperature can still be determined with previous temperature measurements.
As for your question about inquiries about temperature deviation, I’m not sure exactly what you are asking, but there has been significant research put into understanding the divergence effect.
There are no significant issues with the reliability of temperature records to call into doubt the conclusion that the temperatures in the last 10 years are extremely probably the highest in the last several millennia.
Matt says:
October 23, 2010 at 9:08 pm
Lets go over your logic a step at a time.
1. We have some tree ring data.
2. From about 1960 onwards, for unknown reasons, the theory that the tree rings are a proxy for temperature breaks down for this particular data, and the two records “diverge”.
3. Lack of the recent data means that we can’t do a proper calibration/validation on the data.
4. Lack of temperature data in the early part of the record means that we have absolutely no idea of the “divergence problem” exists in the early part of the record.
5. Therefore, it’s fine to use a record that we can’t calibrate, that has a “divergence problem” in recent times, and that we have no idea whether it was affected by the “divergence problem” in previous times.
You sure you want to go with that? Because the NAS didn’t. In the North Report hey recommended that the bristlecones not be used. They didn’t say “oh, just cut off the part that doesn’t fit the theory.” They said DON’T USE THEM.
Now you come along to tell us that throwing away part of a dataset that doesn’t agree with your theories is just fine … and you want us to believe you understand the scientific method?
I would like to apologize for my late reply. Sorry.
What is your reasoning behind your assertion that a “lack of […] recent data means that we can’t do a proper calibration/validation…”?
I have no reason to believe that a proper calibration cannot be done with the data available from 1880 to 1960. Could you explain yours?
What is your reasoning behind your assertion that a “lack of temperature data in the early part of the record means that we have absolutely no idea of the ‘divergence problem’ exists in the early part of the record.”?
I have explained in a previous post that it is not true that we have “absolutely” no idea whether the divergence effect exists before 1880. I will acknowledge that our understanding of the divergence effect and whether it is unique to post-1960 is lacking, but to conclude that the entire tree-growth reconstruction is unreliable is an unreasonable jump in logic.
Cook et al. explain in “Extra-tropical Northern Hemisphere land temperature variability over the past 1000 years” [Edward R. Cook, Jan Esper, Rosanne D. D’Arrigo, Extra-tropical Northern Hemisphere land temperature variability over the past 1000 years, Quaternary Science Reviews, Volume 23, Issues 20-22, Holocene climate variability – a marine perspective, November 2004, Pages 2063-2074, ISSN 0277-3791, DOI: 10.1016/j.quascirev.2004.08.013.
(http://www.sciencedirect.com/science/article/B6VBC-4DCWF1D-3/2/d75d0e6dbbaa582cbf5efab00f082bc9)]:
“Whether or not a similar loss of sensitivity has occurred in the past is unknown with any certainty, but no earlier periods of similar divergence are apparent between the ‘North’ and the other regional chronologies. This result suggests that the large-scale loss of climate sensitivity documented by Briffa et al., 1998a and Briffa et al., 1998b is unique to the 20th century, which argues for an anthropogenic cause.”
For reconstructions prior to the 1200s, no claims can be made about whether there was a similar divergence effect. For reconstructions between the 1200s and 1880, however, it is reasonable to claim that there was no similar divergence effect. Between 1880 and 1960, it is unreasonable to claim that there was a divergence effect. After 1960, it is unreasonable to claim that there was not a divergence effect.
The NAS did not recommend that the bristlecone subset not be used because of the divergence effect. The NAS recommended that the bristlecone subset not be used because they were shown to be much more susceptible to CO₂ than temperature, making them a poor dataset for temperature reconstruction.
To conclude, I ask: what is the point in arguing the invalidity of tree-growth reconstructions?
Are you implying that all temperature reconstructions are invalid?
Would you then imply that the climate science community does not have sufficient understanding of paleoclimatology to assert that the last decade is probably the hottest in human history?
Would you then imply that the climate science community does not have sufficient understanding of climatology to assert that the last century of observed warming is mostly caused by anthropogenic emission of greenhouse gases such as CO₂ and CH₄?
Would you then imply that the climate science community does not have sufficient understanding of anything to assert that if significant and immediate action is not taken to curb global greenhouse gas emissions, it is likely that there will be an increase in negative climate consequences (such as drought, flooding, disease vector migration, etc.)?
Do you think that it is reasonable to believe that line of logic, with the weight of reputable scientific study against it at every level?