Tag Archives: IPCC

McKitrick hides the context

[UPDATE, Nov. 30:  I have added at the end a response from Ross McKitrick (originally posted as a comment at Judith Curry’s website), along with my additional commentary. Also the third paragraph has been slightly amended to clarify that the two out-of-context Phil Jones quotes, misleadingly juxtaposed and reversed by McKitrick, were originally three months apart.]

Son of climategate? SwiftHack 2.0? Dejavugate (as in “deja vu all over again”)? Whichever moniker one prefers for the latest release of stolen CRU emails, it is  very clear that a new round of out-of-context quote mining and error-filled “analysis” is already unfolding. And the leader out of the gate, so to speak, appears to be Ross McKitrick, whose recent National Post piece on the IPCC and the latest batch of stolen emails is now being spread far and wide.

In one particularly outrageous and error-filled passage, McKitrick accuses IPCC  AR4 co-ordinating lead authors Phil Jones and Kevin Trenberth of selecting their team of contributing authors solely on the basis of whether they agree with the pair’s scientific views. He even goes so far as to accuse Jones of “dismissing” (i.e. rejecting as a contributing author) one qualified expert who, supposedly in Jones’s own words, “has done a lot, but I don’t trust him.”

But the record clearly shows that it was Trenberth who made that last comment, and that he was expressing misgivings about the quality of the researcher’s work, not whether he was on the “right side” of scientific issues.  And the expert in question, climatologist Joel Norris, was in fact selected by Trenberth as a contributing author. Even worse, McKitrick has reversed the order of  the  Jones quotes (originally three months apart) , taken them out of context, and then juxtaposed them to make it appear as if they were part of the same exchange. Meanwhile, an examination of the two separate email discussions show chapter co-ordinators trying to fill out their team with authors who will be able to contribute effectively, in complete contradiction to McKitrick’s central thesis.

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Another “climategate” whopper from McIntyre

By Deep Climate

There’s been quite a stir about NCAR Senior Scientist Kevin Trenberth and his upcoming presentation at the American Meteorological Society Annual Meeting. Some of that spilled over here in a spirited discussion of Trenberth’s failure to blockquote a cited paper by Hasselmann (there has since been a new version which appears to be a sincere if hasty fix). The original controversy, though, largely centered on Trenberth’s withering attack on the climate science contrarians and his characterization of them as “deniers” and “charlatans”, which, needless to say, has caused howls of outrage throughout the contrarian blogosphere.

No one has been more outraged by Trenberth’s broadside than Steve McIntyre, who decided to bring what Judith Curry called a “historical perspective” and revisited a “climategate” controversy about “keeping papers out” of IPCC AR4. McIntyre dismissed Trenberth’s defence of Phil Jones as a “first time IPCC writing team member” as “readily demonstrated to be untrue”. McIntyre’s ironclad proof? Despite Trenberth’s claim of being an IPCC “veteran”, both Trenberth and Jones had exactly the same IPCC resume as Chapter 2 contributing authors for the Second and the Third Assessment Reports, before becoming lead authors together in AR4.

I’m sure regular Deep Climate readers will be shocked – just shocked – to find out that a closer look behind McIntyre’s selective facts tells a completely different story. Trenberth was clearly referring to experience as a lead author (contributing authors are not on the “writing team”). And both Jones and Trenberth may have been Chapter 2 contributing authors on previous IPCC reports, but Trenberth was also both a Chapter and Technical Summary Lead Author  in both 1995 and 2001. So, once again, the latest “climategate” scandal proves to be yet another outright falsehood from McIntyre.

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Muir Russell report on CRU: “Their rigour and honesty as scientists is not in doubt”

The long-awaited Muir Russell report on various controversies concerning the work of the Climatic Research Unit (CRU) at the University of East Anglia was released today.

The report thoroughly examined various accusations of improper conduct, and in the main exonerated CRU scientists Phil Jones, Keith Briffa and Tim Osborn of wrongdoing in such areas as scientific research, peer review and the IPCC process, finding that “their rigour and honesty is not in doubt”. The report does criticize CRU, and indeed the University, for a lack of openness, particularly in the handling of freedom of information requests.

There is plenty to digest here, and the report will no doubt generate much commentary in the days to come. For now, though, I’ll present the report’s  summary of findings, along with pointers to previous Deep Climate discussion of some of the issues.

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Revisiting TAR Figure 2-21, part 1: Another false claim from Steve McIntyre

In the “climategate” din, one accusation is shouted perhaps louder and more often than any other: the so-called “trick” supposedly played by IPCC lead author Michael Mann to “hide the decline” in Keith Briffa’s Northern Hemipshere extra tree-ring proxy-based reconstruction, featured along with three others in a key chart in the 2001 WG1 Third Assessment Report (TAR).

According to self-appointed climate science auditor Steve McIntyre, Mann took it on himself to truncate Briffa’s data set and replaced the deleted data with instrumental temperature data, thus creating less of a drop at the end of the resulting smoothed chart. But a closer examination shows the evidence for instrumental “padding” is far from certain. And the difference engendered between different possible “padding” values is minimal in any case.

Even worse, the key element of McIntyre’s narrative, namely the claim that Mann himself truncated Briffa’s data set, is false. In fact, it turns out that the actual data set used by Mann (as sent by Tim Osborn on Keith Briffa’s behalf) contains values only up to 1960 – exactly as in the figure produced in TAR. So once again, we have another egregiously false accusation from Steve McIntyre, one that has been echoed by McIntyre acolytes and CruTape Letters authors Steven Mosher and Thomas Fuller.

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Mike Hulme sets Lawrence Solomon and Marc Morano straight

The latest false scandal in climate science hit the blogosphere over the weekend. National Post columnist Lawrence Solomon [not to be confused with atmospheric chemist and IPCC WG1 chair Susan Solomon] wrote a column with the outlandish claim:

The UN’s IPCC misled the press and public into believing that thousands of scientists backed its claims on manmade global warming, according to Mike Hulme, a prominent climate scientist and IPCC insider.

Charges of  a “phony UN IPCC consensus” are already reverberating on contrarian blogs around the world, thanks to the quick efforts of climate science disinformation specialist Marc Morano.

But now Mike Hulme, a professor of climate change at the University of East Anglia, has set the record straight. His “correcting and clarifying” statement is unambiguous in its disavowal of Solomon’s and Morano’s misinterpretation:

I did not say the ‘IPCC misleads’ anyone – it is claims that are made by other commentators, such as the caricatured claim I offer in the paper, that have the potential to mislead.

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How to be a climate science auditor, part 2: The forgotten climategate emails

In this installment, I’ll look at another technique in the climate auditor’s toolbox, namely selective quotation. Once again, our example case study will involve accusations by Steve McIntyre concerning the use of paleoclimatologist Keith Briffa’s tree-ring based reconstruction in a key figure from the IPCC Third Assessment Report.

Arguing from a cherrypicked selection of quotes from the “Climategate” emails, McIntyre has claimed that IPCC authors Chris Folland and Michael Mann pressured Briffa to submit a reconstruction that would not “dilute the message” by showing “inconsistency” with multi-proxy reconstructions from Mann and Briffa’s CRU colleague Phil Jones. Briffa “hastily re-calculated his reconstruction”, sending one with a supposedly larger post-1960 decline before. According to McIntyre, Mann resolved this new “conundrum” and simply “chopped off the inconvenient portion of the Briffa tree-ring data”.

But a review of the emails – including some that have never been quoted before – clearly contradicts McIntyre’s version of events:

  • Jones and Briffa were concerned that Mann had an outdated version of the Briffa reconstruction, and both urged the adoption of the newer “low frequency” one, more appropriate for comparison with other multi-century reconstructions.
  • Far from pressuring Briffa to change his reconstruction right away, Mann questioned whether an immediate change was required, or even possible, and counselled waiting for the next revision.
  • CRU colleague Tim Osborn advised Mann that he and Briffa “usually stopped” the “low frequency” reconstruction in 1960, and went one better in his later “resend” to Mann, by explicitly removing the post-1960 data.

I’ll also show how McIntyre has changed his narrative along the way , in an effort to prove that the true “context” of the famous “trick” to “hide the decline” is somehow an indictment of the IPCC. (Speaking of which, be sure to take the poll at the end about McIntyre’s next move). But first, once again, here is the cause of all the fuss, namely Figure 2-21 from Chapter 2 of the IPCC Third Assessment Report – Working Group I: The Scientific Basis (2001).

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McIntyre provides fodder for skeptics

[This post was updated on December 12 to provide additional context that strengthens the original analysis – see below for details.]

This so-called Climategate is really getting out of hand, isn’t it?

Steve McIntyre has published allegations – twice now – that an internal IPCC authors’ debate about the inclusion of Briffa’s tree-ring reconstruction in a key figure from the 2001 WG1 Third Assesement Report was driven by concern about the post-1960 “decline” in tree-ring widths, a decline that showed a marked divergence with the instrumental tempertaure record.

The Climategate Letters show clearly that the relevant context is the IPCC Lead Authors’ meeting in Tanzania in September 1999 at which the decline in the Briffa reconstruction was perceived by IPCC as “diluting the message”, as a “problem”, as a “potential distraction/detraction”. [Emphasis added]

McIntyre even claims that lead author Michael Mann worried that showing the series with this decline would give “fodder” to “skeptics”.

But even a cursory examination of the emails in question shows that the discussion was really about other aspects of the reconstruction, specifically obvious discrepancies between Briffa’s reconstruction and the other two under consideration over the major part of the reconstruction’s length. Thus, once again, McIntyre’s speculations are shown to be utterly without foundation.

Even worse, McIntyre left out intervening sentences within the actual proffered quotes in what appears to be an unsophisticated attempt to mislead.

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