As readers likely know, I have long followed The Hockey Stick Debate. It is, in fact, the reason I became interested in the global warming discussion. And while I've written about it a fair amount in the past, to the point of writing two (short) eBooks on the subject, I haven't discussed it much in some time. The reason is simple - the debate has largely died off.
I could go on and on about how climate science has largely abandoned the infamous Hockey Stick, claiming to support it while only publishing results very different from it, but the reality is climate scientists have largely tried to distance themselves from the subject. I suspect they have largely because the problems surrounding the subject became too much for them to bear, meaning a tactical retreat was in order.
Whatever the reason, the point is debates over paleoclimatic reconstructions have died down so much there's been little reason for me to write about them until today. Today, a new story has broken which will be a source of great interest. I came across the news because I saw a link to a news article whose headline says:
How a single word sparked a four-year saga of climate fact-checking and blog backlash
This caught my eye for a variety of reasons, including my interest in the rise in "fact-checking" by the media (which often isn't really fact-checking). Naturally, I clicked on it. I never anticipated it'd be about a subject I know well, a 2012 paper by Joelle Gergis and co-authors.
There's a lot of backstory to this topic, and I'm not going to go into it today. Today, I just want to give people a brief introduction to the subject. According to the article:
Following the early online release of the paper, as the manuscript was being prepared for the journal’s print edition, one of our team spotted a typo in the methods section of the manuscript.
While the paper said the study had used “detrended” data – temperature data from which the longer-term trends had been removed – the study had in fact used raw data. When we checked the computer code, the DETREND command said “FALSE” when it should have said “TRUE”.
Both raw and detrended data have been used in similar studies, and both are scientifically justifiable approaches. The issue for our team was the fact that what was written in the paper did not match what was actually done in the analysis – an innocent mistake, but a mistake nonetheless.
Instead of taking the easy way out and just correcting the single word in the page proof, we asked the publisher to put our paper on hold and remove the online version while we assessed the influence that the different method had on the results.
The difference between using detrended and non-detrended data is an important one, and the choice of which to use raises all sorts of questions and concerns. That's a topic for another day, but a key point to understand is the reason Gergis et al had thought to use detrended data in their methodology was to rebut criticisms related to things like a problem known as the Screening Fallacy. While Gergis now claims this error was merely a "typo" of "a single word in a 74-page document," the reality is the intended analysis was always supposed to have been done on detrended data. That is why authors of the paper, including Gergis herself, wrote things like:
Although it was an unfortunate data processing error, it does have implications for the results of the paper. We wish to alert you to this issue before the paper goes into final production.
This was an error in analysis, not a "typo" that made consisted only of "a single word in a 74-page document." Additionally, while Gergis claims that it was her and her co-authors decision to have the paper put on hold instead of "just correcting the single word in the page proof," the reality is the paper was rejected because of this error. Journal of Climate editor John Chiang wrote to Gergis:
After consulting with the Chief Editor, I have decided to rescind acceptance of the paper- you’ll receive an official email from J Climate to this effect as soon as we figure out how it should be properly done. I believe the EOR has already been taken down.
Also, since it appears that you will have to redo the entire analysis (and which may result in different conclusions), I will also be requesting that you withdraw the paper from consideration. Again, you’ll hear officially from J CLimate in due course. I invite you to resubmit once the necessary analyses and changes to the manuscript have been made.
I hope this will be acceptable to you. I regret the situation, but thank you for bringing it to my prompt attention.
Gergis later wrote to Chiang:
Just to clarify, there was an error in the words describing the proxy selection method and not flaws in the entire analysis as suggested by amateur climate skeptic bloggers.
Over recent days we have been in discussion with colleagues here in Australia and internationally about the use of detrended or non detrended data for proxy selection as both methods are published in the literature .
People have argued that detrending proxy records when reconstructing temperature is in fact undesirable (see two papers attached provided courtesy of Professor Michael Mann) .
While anthropogenic trends may inflate correlation coefficients, this can be dealt with by allowing for autocorrelation when assessing significance. If any linear trends ARE removed when validating individual proxies, then the validation exercise will essentially only confirm the ability of the proxies to reconstruct interannual variations. However, in an exercise of this nature we are also intrinsically interested in reconstructing longer-term trends. It therefore appears to be preferable to retain trends in the data, so that we are also assessing the ability of the proxies to reconstruct this information.
Both approaches have been widely used in the past, and that both are supported in the literature. Thus we believe that either approach is entirely justifiable. In terms of revisions to our paper, we plan to compare the influencing of using detrended and non detrended proxy selection in a supplementary section but it is very unlikely to result in a rewrite of the paper. Instead, there will be correction of the correct method used in the paper and reference to additional supplementary material where appropriate.
Given this paper was originally submitted for review on 3 November 2011 and was extensively reviewed by three expert assessors, my strong preference would be for permission to submit a revision of the original manuscript rather than an entirely new submission. That said, we will of course follow your advice on how best to proceed.
The journal's Chief Editor Anthony Broccoli saw this and pointed out the inconsistency in Gergis's description, as previously she said it was "an unfortunate data processing error" yet now wrote "there was an error in the words describing the proxy selection method":
Your latest email to John characterizes the error in your manuscript as one of wording. But this differs from the characterization you made in the email you sent reporting the error. In that email (dated June 7) you described it as “an unfortunate data processing error,” suggesting that you had intended to detrend the data. That would mean that the issue was not with the wording but rather with the execution of the intended methodology.
Would you please explain why your two emails give different impressions of the nature of the error?
Both Tony and I read your initial email (dated June 8 for me, I’m in Taipei) to mean that you had intended to detrend during the predictor selection, but that subsequently you had discovered that you had not. Given that you had further stated that “Although it was an unfortunate data processing error, it does have implications for the results of the paper,” we had further took this to mean that you were going to redo the analysis to conform to the description of the proxy selection in the paper.
Assuming this to be true, my reasoning was that since you are likely to use a different subset of proxies in the recalculation, it allows for the possibility of a significantly different result and conclusion. It was on this basis that I requested that you resubmit the paper (and not because of flaws in the analysis method). I understand that the results may well remain essentially the same after the redo, but this is not something that I can assume to be true .
The communication between Gergis, her co-authors and the journal show this was not merely some "typo" that could be fixed by changing "a single word in a 74-page document." Similarly, that communication shows it was not Gergis or her co-authors decision to have the paper taken offline and its publication put on hold. In fact, the opposite was true. Gergis and her co-authors attempted to simply dismiss the problem as a "typo," but the editors of the Journal of Climate wouldn't accept their argument.
There is much more to this story, including details about how the paper was re-submitted and eventually published four years later, as well as technical points about things like why using non-detrended data would have been wrong. I'm sure many will come up and be discussed over the next few weeks. For now though, I just want to draw people's attention to this development and highlight a bit of how utterly false the narrative being spun by people like Joelle Gergis is.
As a final note, while Gergis writes:
It turned out that someone else had spotted the typo too. Two days after we identified the issue, a commenter on the Climate Audit blog also pointed it out.
The website’s author, Stephen McIntyre, proceeded to claim (incorrectly) that there were “fundamental issues” with the study. It was the start of a concerted smear campaign aimed at discrediting our science.
I should point out I am not part "of a concerted smear campaign," and if she believes I am, she is paranoid. Also, her claim she and her co-authors "spotted the typo" two days prior to anyone else is simply false. The e-mail communication between her and her co-authors shows that is false beyond any doubt.
That and other falsehoods by Joelle Gergis are matters for another day though.
July 13, 10:50 PM Update: I submitted a comment to the site hosting Joelle Gergis's article which pointed out the article contains a number of falsehoods. It was only a few paragraphs long, focused solely on issues raised in the article and didn't use any sort of inappropriate language or tone. This is the result:
— Brandon S? (@Corpus_no_Logos) July 14, 2016
Maybe I need to start taking screenshots of any comments I post.anywhere. Censorship seems the norm anymore.