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Climategate: Hiding the Decline?

Posted on 22 November 2010 by James Wight

This is the third part in a series on the fake scandal of Climategate (start here).

A second set of allegations relate to the University of East Anglia Climatic Research Unit (CRU)’s paleoclimate reconstructions, which use tree rings as a proxy for temperature change. Although this is a relatively obscure branch of climate science, it was prominently featured in the Summary for Policymakers of the IPCC Third Assessment Report (TAR). Consequently, it has become a prime target for contrarians; as the Muir Russell Review puts it, they have long argued that the way CRU handled data was “intended to bias the scientific conclusions towards a specific result and to set aside inconvenient evidence.”

In what is probably the most notorious of the CRU emails, dated 16/11/1999, Jones wrote:

I’ve just completed Mike’s Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) and from 1961 for Keith’s to hide the decline.

This email is often quoted by commentators with little or no understanding of what it refers to, so it is worth taking some time to explain the context. Jones was discussing a graph for the cover of an obscure 1999 World Meteorological Organisation (WMO) report, which depicted both instrumental temperature data and reconstructed temperatures based on tree rings. The “decline” refers to the fact that some tree ring series (though not all) diverge from instrumental records in recent decades, for reasons that are not fully understood (although there are grounds for believing it is only a recent phenomenon). The “trick” was a way of presenting the data in this one particular graph, namely to truncate the tree ring data at the point when it diverged.

Anyway, contrarians take the use of the words “trick” and “hide the decline” as evidence that this was done to deceive, and this was the allegation that the inquiry examined. More generally, the contrarians claim that the divergence problem “may not have been properly taken into account when expressing the uncertainty associated with reconstructions”.

Contrarians have also accused CRU researchers (in particular their leading expert on tree ring reconstructions, Keith Briffa) of cherry-picking tree ring series that would produce a favoured result, namely that the late 20th century was warmer than the Medieval Warm Period. They allege that Briffa’s selection of an obscure tree ring chronology from the Yamal peninsula in Siberia “had an undue influence on all of the lines appearing in Chapter 6 of the 4th IPCC Report” (AR4); and that CRU withheld access to the Yamal data. And they use all these alleged flaws in CRU’s work to claim that less confidence should be placed in the conclusions of that AR4 chapter (specifically, the conclusion that current temperatures are likely the warmest in 13 centuries).

Regarding the “hide the decline” email, Jones has explained that when he used the word “trick”, he simply meant “a mathematical approach brought to bear to solve a problem”. The inquiry made the following criticism of the resulting graph (its emphasis):

[T]he figure supplied for the WMO Report was misleading. We do not find that it is misleading to curtail reconstructions at some point per se, or to splice data, but we believe that both of these procedures should have been made plain — ideally in the figure but certainly clearly described in either the caption or the text. [1.3.2]

But this was one isolated instance that occurred more than a decade ago. The Review did not find anything wrong with the overall picture painted about divergence (or uncertainties generally) in the literature and in IPCC reports. The Review notes that the WMO report in question “does not have the status or importance of the IPCC reports”, and concludes that divergence “is not hidden” and “the subject is openly and extensively discussed in the literature, including CRU papers.” [1.3.2]

As for the treatment of uncertainty in the AR4’s paleoclimate chapter, the Review concludes that the central Figure 6.10 is not misleading, that “[t]he variation within and between lines, as well as the depiction of uncertainty is quite apparent to any reader”, that “there has been no exclusion of other published temperature reconstructions which would show a very different picture”, and that “[t]he general discussion of sources of uncertainty in the text is extensive, including reference to divergence”. [7.3.1]

Regarding CRU’s selections of tree ring series, the Review does not presume to say whether one series is better than another, though it does point out that CRU have responded to the accusation that Briffa misused the Yamal data on their website. The Review found no evidence that CRU scientists knowingly promoted non-representative series or that their input cast doubt on the IPCC’s conclusions. The much-maligned Yamal series was included in only 4 of the 12 temperature reconstructions in the AR4 (and not at all in the TAR).

What about the allegation that CRU withheld the Yamal data? The Review found that “CRU did not withhold the underlying raw data (having correctly directed the single request to the owners)”, although “we believe that CRU should have ensured that the data they did not own, but on which their publications relied, was archived in a more timely way.” [1.3.2]

In summary, while the inquiry did criticize an individual graph, it found no evidence of CRU intentionally manipulating tree ring data or downplaying the associated uncertainties to mislead the public.

Next: Perverting Peer Review?

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Comments 51 to 100 out of 103:

  1. Albatros #48 Ideological Rant? dear dear - a perfectly reasonable comment I would have thought. Phila #49 In other words Prof Jones did lose the original data (was it something about not enough hard disk space back then?) - but if anyone cares to back-engineer all his documented corrections to it from the current result (back to the 1980's), then it can be resurrected. Sounds like a job for M&M. A spot of sloppy record keeping is only to be expected of those promoting 'the greatest moral challenge of our age'.
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  2. Re: Ken Lambert You know, if "repeated ideological rants" were added to the Comments Policy, then perhaps you'd have no comments left on threads anymore. The Yooper
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  3. KL #51 "A spot of sloppy record keeping is only to be expected of those promoting 'the greatest moral challenge of our age'. " You know, this is really tiresome. I think I'll take what is and isn't acceptable record keeping for scientists from scientists, rather than from an ideologically fixated engineer with a terminal case of confirmation bias.
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  4. so when tree ring data diverges from the predicted theory or instrument data we throw out the tree ring data and overlay the instrument data. i've always had an issue with that. if the proxy data is not valid then don't use it for prior periods. that is the essence of cherry picking. there is no way to gloss over the 'hide the decline' statement in my humble opinion. if we throw out proxy data in the recent period because we think there was a drought condidtion then how do we know the prior proxy data were also not influenced by climate issues that we can't verify since they happened before instrument data? we still can't explain why the past decade has shown no increase in temperatures even though CO2 continues to increase at a linear rate. the following website shows that temperatures and OLR are not following the predicted models. something else besides CO2 is driving our climate.
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    Moderator Response: It is not true that "the past decade has shown no increase in temperatures." See (and please comment on one of these threads, not this thread, for that topic): "It's Cooling," "It Hasn't Warmed Since 1998," "Global Temperatures Dropped Sharply in 2007," "Keep Those PJs On: La Nina Cannot Erase Decades of Warming," and "European Reanalysis of Temperature Confirms Record Warmth in 2010." Regarding temperature's correlation with CO2, see "There’s No Correlation Between CO2 and Temperature," and if you want to discuss that topic, do so on that thread.
  5. Re #44 JMurphy wrote "it was all a big conspiracy (along with all those other enquiries, which came to the same result), but you have exposed the hidden truth by your dogged determination." Oh dear! Oh dear! In the OP this thread cites the Muir Russell Review as saying:- "We do not find that it is misleading to curtail reconstructions at some point per se, or to splice data, but we believe that both of these procedures should have been made plain — ideally in the figure but certainly clearly described in either the caption or the text.” [1.3.2]" And then tries to defend this by saying :- "But this was one isolated instance that occurred more than a decade ago. The Review did not find anything wrong with the overall picture painted about divergence (or uncertainties generally) in the literature and in IPCC reports." One isolated instance? So why did the IPCC when adopting this flawed data use just one isolated instance as a major argument in its Assessment Reports? No, JMurphy, this is nothing to do with conspiracy theories or dogged determination but everything to do with scientists employed at public expense trying, however sincerely, to make the evidence fit the hypothesis and an all too gullible international quango being lead by the nose.
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    Moderator Response: The IPCC did not use the same graph that appeared on the cover of the 1999 WMO report. They used a similar graph which the Review apparently had no problem with. - James
  6. damorbel #55 "this is nothing to do with conspiracy theories or dogged determination but everything to do with scientists employed at public expense trying, however sincerely, to make the evidence fit the hypothesis and an all too gullible international quango being lead by the nose. " Even if we take the idea that the "Nature trick" was dodgy, you have to ask the question: what material difference to the scientific conclusions would be made by discarding this data analysis? The answer to this question is none at all. Unless you have some evidence to present, rather than just opinionated assertion with no basis in evidence.
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  7. After all the enquiries, it is astonishing to find deniers demanding that the enquirers be themselves enquired into. Or, "let's keep having enquiries until they reach the conclusions we want".
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  8. Re #56 kdkd You wrote:- "Even if we take the idea that the "Nature trick" was dodgy, you have to ask the question: what material difference to the scientific conclusions would be made by discarding this data analysis?" I take it you are referring to the CRU substituting thermometer measurements for tree ring measurements for the 20thC section of the 'hockey stick' temperature graph? This 'unidentified' substitution avoided disclosing the fact that the tree ring record does not show the temperature rising in the 20thC. I am not providing new evidence of temperature trends, just drawing attention to the Muir Russell Review which says that substituting the instrumental (thermometer) record without identifying the substitution is unacceptable.
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  9. Re #57 No, tobyjoyce, no need to for "the enquirers be themselves enquired into", just read what they write!
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  10. damorbel #58 I've seen much worse in the peer reviewed literature. This doesn't seem to be a damning inditement to me, more a side issue that the so-called-sceptics can (as usual) blow up out of all proportion to its importance.
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  11. damorbel wrote : "One isolated instance? So why did the IPCC when adopting this flawed data use just one isolated instance as a major argument in its Assessment Reports?" Two assertions there (concerning the data and the IPCC), neither with any proof. Perhaps you don't need any ? Until you back up your 'arguments', you are just blindly repeating whatever you've read elsewhere.
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  12. damorbel wrote : "I am not providing new evidence of temperature trends, just drawing attention to the Muir Russell Review which says that substituting the instrumental (thermometer) record without identifying the substitution is unacceptable." You are certainly, though, providing new interpretations of Muir Russell, which says nothing like what you claim.
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  13. Re #62 JMurphy you wrote:- "Muir Russell,which says nothing like what you claim." Perhaps my copy and past isn't working! Do tell me what I should have seen.
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  14. damorbel #63 I believe that you are insinuating that the use of the 'Nature trick' has major consequences for the conclusions that we should draw from the larger body of scientific knowledge. Do you have evidence for this, or is this just more pointless bluster from a so-called sceptic?
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  15. damorbel wrote : "Perhaps my copy and past isn't working! Do tell me what I should have seen." All you have to do is look at the report, do a search for the word 'unacceptable' (or any similar word) and see how the results relate to your claim that Muir Russell says that "substituting the instrumental (thermometer) record without identifying the substitution is unacceptable". What do you find ?
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  16. Damorbel, My last post to you-- then as far as I'm concerned you can keep yelling about conspiracies into space. Please very carefully read the post by JMurphy here. The critique has been acknowledged. The splicing refers to the front cover schematic from a single obscure WMO report back in 1999. It has nothing to do with the IPCC assessment reports as you falsely claim. Why do 'skeptics' have such a horrid time applying the correct context and with fact checking? Please actually read some of the scientific literature published on the divergence issue with certain dendro chronologies in the last 20th Century (e.g.., Yamal). I provided a hyperlink for a Google scholar search here. Actually your attempts here to fabricate a 'debate' on a non-issue (the WMO cover schematic) and insistence on making multiple unsubstantiated accusations of wrong doing continues to undermine what little, if any, credibility most self-professed 'skeptics' have. So perhaps I should be encouraging you to continue....either way you are wasting both your time and that of others. Sorry for the terse comment, but I've simply run out of patience.
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  17. JMurphy, You have the patience of a saint. Thank you for your efforts!
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  18. Re #65 JMurphy you wrote:- "All you have to do is look at the report," Since I have already cited paragraph 23 (p13) of the report (cited in the OP) as the main thrust of my contribution, I think you will agree that for me to do a search based on your recommendations would be wasting my time; but then I have no objection to reading the results of a search done by you using your own recommendations. You have of course read the relevant paragraph as cited in the OP?
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  19. Re #66 Albatross, you wrote:- "the splicing refers to the front cover schematic from a single obscure WMO report back in 1999. It has nothing to do with the IPCC assessment reports as you falsely claim". If that is the case, why does paragraph 23 of the Muir Russell Report read as follows:- "in respect of a 1999 WMO report figure .... we find that, given its subsequent iconic significance (not least the use of a similar figure in the IPCC Third Assessment Report)"? Oh yes, I have the patience of a Saint too!
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  20. damorbel: "...they both are consequences of the kind of bad science done at CRU." Which produced temperature anomaly results nearly identical to those of AGW skeptics Spencer & Christy at UAH. Therefor AGW skepticism is clearly all a vast conspiracy of nonsense with no scientific basis! Thank you for introducing me to 'skeptic' logic. With this tool at the ready I can 'prove' ANYTHING!
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  21. Albatross wrote : "You have the patience of a saint." Well, it's not really that difficult when all you have to work against are comments like these from damorbel, which have no basis in reality but are the interpretations of someone who doesn't want to accept AGW : There is not the slightest doubt that Muir Russell identified the failure to draw attention to the source of the 20thC data used to substitute for the 'off message' tree rings as a serous deficiency. There is more than doubt because you have interpreted that in the way that you want to. If that is the case, why does paragraph 23 of the Muir Russell Report read as follows:- "in respect of a 1999 WMO report figure .... we find that, given its subsequent iconic significance (not least the use of a similar figure in the IPCC Third Assessment Report)"? As Albatross wrote, that has no effect on anything in any IPCC Reports. Reading the whole paragraph that you have butchered, you can see what the reality is : On the allegation that the references in a specific e-mail to a „trick‟ and to „hide the decline‟ in respect of a 1999 WMO report figure show evidence of intent to paint a misleading picture, we find that, given its subsequent iconic significance (not least the use of a similar figure in the IPCC Third Assessment Report), the figure supplied for the WMO Report was misleading. We do not find that it is misleading to curtail reconstructions at some point per se, or to splice data, but we believe that both of these procedures should have been made plain – ideally in the figure but certainly clearly described in either the caption or the text. Surely you can work out what could be classed as misleading (a picture on the cover of a WMO report) and what isn't, i.e. the data or the way it may have been used subsequently ? I am not providing new evidence of temperature trends, just drawing attention to the Muir Russell Review which says that substituting the instrumental (thermometer) record without identifying the substitution is unacceptable. Still not representative of anything in the Muir Russell Report, no matter how many times I look at your interpretation and the reality again. In fact, there are no references to "deficiencies" or anything "unacceptable", with regard to this matter. Perhaps there are two versions of the report - the real one and the one that so-called skeptics have interpreted for their own ends ? One isolated instance? So why did the IPCC when adopting this flawed data use just one isolated instance as a major argument in its Assessment Reports? Still no information forthcoming as to what this relates to, with regard to "flawed data" or the Assessment Reports. Still waiting for examples. I am also still waiting forlornly for answers to the questions I asked previously : Do you believe all "dendrochronological" data is fiction, or are you referring to a particular set of data ? Do you believe that "dendrochronological" data (i.e. temperature reconstruction) gives a more accurate reading for temperature in the 20th Century than thermometers ? Have you ever heard of the Divergence Problem ? What are you referring to when you write "the method and location of the measurements were different" ?
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  22. Re: damorbel (70,71) (70) So, you're prepared to show, via evidenciary process, specifically how the WMO figure used led to the figure used in the TAR; and to specifically discuss those similarities in the figures themselves. After all, I'm sure you've done your homework to support your allegations of wrongdoing that would entail not only a 7th investigation into "climategate" but an additional investigation into the Muir Russell commission itself? Because that is what you're claiming, right? Or is it that all you have is a case for logic in absencia (and there's nothing saintly about that)? (71) This is what the Muir Russell report did not clear CRU of: 1. Sloppy record keeping 2. Having a kind of crappy attitude 3. Failing to properly annotate or explain via comment the specific nature of a graph used on the WMO 1999 Report cover (where admittedly, from a graphic arts perspective, proper annotation would have played havoc with the presentation...perhaps the WMO should have repeated the graph in the report with the proper explanatory text...so it's all the WMO's fault!!!). So, whatcha got? If something substantive, I expect you to write it up & submit it (Tip: E&E have a track record for publishing material like this, I'm sure they would make room for it) for publication. Fame and fortune await you. Or you've got nuttin'. Which is it? PS: I'm tired of the constant injection of unsupported innuendo and invective into this thread by those who see nothing but what they wish to see, instead of what verifiable sources actually say (this last bit not aimed specifically at you, damorbel, though portions of it certainly do apply). The Yooper
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  23. CB, Try and wrap your head around this logic: "...they both are consequences of the kind of bad science done at CRU." Hmm, yet skeptics (e.g., Lindzen and Michaels) frequently cite the CRU temperature data to advance their arguments that the planet is not warming much or to claim that the models are overestimating the amount of warming. So CRU science/data is only crap when it is advancing your belief that climate scientists are "incompetent", but when you want to show allege that the warming is not that bad, then CRU data suddenly become a perfectly credible source again. Also note, from post #70, "similar" does not mean "the same". Isn't it now almost 2011? Yet some people seem stuck somewhere between 1999 and 2001.
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  24. Albatross wrote: "So CRU science/data is only crap when it is advancing your belief that climate scientists are "incompetent", but when you want to show allege that the warming is not that bad, then CRU data suddenly become a perfectly credible source again." I know! Isn't it wonderful!? With new improved 'Skeptic' Logic (tm, patent pending) it is now possible to firmly believe two mutually exclusive things at the same time. Just think of the possibilities!
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  25. JMurphy @75, Thanks. For those wondering, more about the divergence problem can be found in a Nature paper here.
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  26. 77.Albatross There would be no logic problem in suggesting a data set is insufficient to prove A while at the same time being sufficient to disprove B. You'll have to be more specific to allow us to make a call on that.
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  27. kdkd #56 "Even if we take the idea that the "Nature trick" was dodgy, you have to ask the question: what material difference to the scientific conclusions would be made by discarding this data analysis" A post of mine has already been deleted on this matter. Please re-instate it if your SS blog is to be taken seriously. Perhaps now is the time to note that kdkd is also a 'Moderator' on this blog and has the power to purge my and other posts without explanation. If the Moderators of this(to date)excellent blog start purging opposition views whilst being partisan AGW contributors themselves - then they will end up talking to themselves and therefore stifling proper debate.
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    Moderator Response: Three of your posts have been deleted. One contained direct accusations of tax fraud, and two more contained graphic descriptions of the alleged sexual practices of those who disagree with you. None of those were appropriate for this site, and the decision to delete them was straightforward. (Also, to address your concern, please note that none of them were moderated by kdkd or any other individual involved in the debate with you).
     
    Moderating this site is a tiresome chore, particularly when commenters repeatedly submit offensive or off-topic posts. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site.
     
    Finally, please understand that moderation policies are not open for discussion in comment threads. If you would like to compliment or complain about the site's moderation policies or how they are implemented, please do so via email to John Cook.
  28. You know, Damorbel, the Global Warming Policy Foundation (a well known skeptic group), use as their logo a graph which purportedly shows global cooling over the last decade. Of course that graph contains a significant error for the year of 2003 & only covers the period of 2001-2008 (a very serious case of cherry picking). MacLean, another climate skeptic, spliced together weather balloon & satellite temperature anomalies in order to "hide the incline"-& didn't mention it anywhere in his paper-even though the paper's conclusions rested almost entirely on this spliced data. So, no doubt you're going to want to see some serious inquiries done into both of these cases of "unacceptable" behaviour-or does that only apply to people who are putting out views that you disagree with?
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  29. Another point, Damorbel. From my reading of Briffa's data, the divergence doesn't kick in until the 1960's &-as I've said elsewhere-is believed to be the result of long-term drought conditions in the area. As I also said before, this divergence does highlight the danger of using tree-ring data as a proxy where direct temperature measurements are already available. It certainly doesn't reveal any malfeasance on the part of Jones or Briffa-no matter how much you try & spin Muir's findings. As to the impact of this divergence on the role of dendrochronology in Paleo-climate work-it doesn't really effect it at all, as long as you have other proxies to which you can compare the data. So, at the end of the day, this is a "controversy" only in the minds of skeptics like yourself-not in actual reality!
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  30. Marcus #81 There is a simpler explananion: After 1960, the tree ring data did not fit the rising thermometer record - so the tree ring 'decline was hidden' by truncation. Of course thermometer temperatures have been around since about 1860 (100 years prior to 1960) so why should the tree rings from 1860 to 1960 be included at all? Well clearly the reason is that they formed one of those 'multiple lines of evidence' right up until 1960 - when ...well they didn't any more so were simply discarded. All this shows is that tree rings were probably unreliable proxies - all through the time series and that they were used only to support the narrative of increasing warming up until they started to diverge. That is the dodgy part of the 'Nature' trick. The argument then goes - if one bit of this 'science' is dodgy - how do we know that the rest is rock solid - it is called credibility - and that is what all the Climategate fuss is about.
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  31. #81 Marcus at 09:38 AM on 24 November, 2010 the divergence doesn't kick in until the 1960's The simplest explanation is Andrew Ellicott Douglass died on March 20, 1962 (at an age of 94). Up to that time tree ring data were kept in sync with climate out of respect for his climate - sunspot cycle theory. After that things started to deteriorate rapidly and climate diverged from solar activity. In this upheaval trees, for his honor alone, decided to follow sunspots, not climate.
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  32. KL @ #82: "The argument then goes - if one bit of this 'science' is dodgy - how do we know that the rest is rock solid - it is called credibility - and that is what all the Climategate fuss is about." Except that is not a logical argument in any way, shape or form--and that's even if we assume for the sake of this post that the "Nature trick" does cast doubt on the reliability of tree-ring proxies. Baby, bath water, and all that.
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  33. KL, Your "arguments" make no sense whatsoever. Do you now deny that the planet has warmed since 1960? The other day you told me that you agree the planet has warmed. So why keep a specific chronology if it is well-established that the trees in the Yamal region, for some reason, are no longer behaving as suitable thermometers? You seem to think that the "divergence problem" applies to all the dendro chronologies, it does not. Would you rather that they used misleading and erroneous paleo data even though scientists knew from multiple, independent observational data that the planet had warmed quite a bit since 1960? Sorry, but you really do need to learn more about paleo reconstructions and dendro chronology, before opining on these matters. Your comments thus far, indicate that you are only too happy to believe/see whatever fits your ideology, even if it means ignoring the facts and science. Nothing nefarious is going on here; really there isn't. And the data were not "simply" discarded as you claim. As you and others have been told multiple times, several papers have been written on the "divergence problem" going back to 1998.
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  34. BP #83 If you're going to post conspiracy theory nonsense, at least either present evidence, or make it clear that you're "joking"
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  35. KL # Various I see you still can't get over the idea that you've got to look at more than just the temperature data.
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  36. Albatros #85 "Nothing nefarious is going on here; really there isn't. And the data were not "simply" discarded as you claim. As you and others have been told multiple times, several papers have been written on the "divergence problem" going back to 1998." Oh, OK so the divergence problem is something peculiar only to the 20th century and only after 1960?? So it is fine going back to say AD1560, or AD1060 or however old these trees are? And how do we know that? Furthermore - we all seem to agree that Jones 'lost' the original raw data - and we could reconstruct it by taking CRU's reconstruction and 'back-winding' it using Jones' documented correction methods in the published literature? Has anyone done that in order to verify what the raw data was, and whether it had been 'corrected' correctly?
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    Moderator Response: The divergence from temperatures since the 1960s is seen in only some tree ring series, in particular those at high northern latitudes. However, both the diverging and non-diverging tree rings are in good agreement back to the Medieval Warm Period. – James
  37. KL #88 "So it is fine going back to say AD1560, or AD1060 or however old these trees are? And how do we know that?" Good agreement with ice core data and other proxies. More recently (pre-1960) you can show that the thermometer record and the tree ring proxies are in good agreement, but after that there's a decline in reliability of the proxies. So hiding the decline refers to this. "Hide" in this instance is a shorthand for "producing a graph that is straightforward for the reader to view and interpret". I suspect that given that there is good independent validation with other records, reverse engineering the original raw data would be seen as an ineffective use of limited resources. If the CRU had realised that the data set was going to be so important, they would have curated is better in the early days (I hit that problem from time to time with my work too, although these days I have a very effective process).
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  38. kdkd #89 "Hide" in this instance is a shorthand for "producing a graph that is straightforward for the reader to view and interpret". I assume you are joking with this preposterous explanation. The tree ring issue is not important enough for me to drill down into the proxies and study their methodologies. Whether the MWP was warmer or cooler than the present is not as critical as monitoring OHC, SLR and trying to work out WV-CO2 feedback interactions and the magnitude of TOA imbalances. As far as CRU 'losing' the raw data - the advantage of being 50+ is that you can remember (just) the state of computer technologies going back 30 years. Twenty years ago you could get 1.44MB onto a 3.5" floppy. A big HDD was 340MB. 250MB on a Travan tape drive. 250MB is a lot of data in a simple format of that era. You could store a helluva lot of numbers in simple text files on tapes or even floppies. Lack of storage space seems like a convenient excuse which might impress the kiddies used to GB not MB.
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  39. Re: Ken Lambert (90) I too go back a ways, to the days of punch cards, when even a dummy terminal with a baud rate in kb was a pipe dream. Given that, if the "lost" data was already in digital form, I also share your credulity about the 'lack of storage space' just 20 years ago (I was working with near-Gb-sized files saved to tape even then). However, I am not informed enough on that particular aspect to then proceed into conflation & conspiracy. If you can work out some particulars on that aspect & share, I'd be interested in knowing more. Just wanted you to know I thought you had a good point there. The Yooper
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  40. @88, KL says: Oh, OK so the divergence problem is something peculiar only to the 20th century and only after 1960?? And: So it is fine going back to say AD1560, or AD1060 or however old these trees are? And how do we know that? Oh please, KL. For instance: Wilmking, M., R. D'Arrigo, G. C. Jacoby, and G. P. Juday (2005), Increased temperature sensitivity and divergent growth trends in circumpolar boreal forests, Geophys. Res. Lett., 32, L15715, doi:10.1029/2005GL023331 This recent, widespread divergence in growth response seems unique over the past three centuries, and may relate to different microsite responses of individual trees to temperature-induced drought stress or other factors. Or: K. R. Briffa, T. J. Osborn and F. H. Schweingruber, Large-scale temperature inferences from tree rings: a review These ‘hemispheric’ summer series can be compared with other reconstructions of temperature changes for the Northern Hemisphere over the last millennium. (..) However, in many tree-ring chronologies, we do not observe the expected rate of ring density increases that would be compatible with observed late 20th century warming. This changing climate sensitivity may be the result of other environmental factors that have, since the 1950s, increasingly acted to reduce tree-ring density below the level expected on the basis of summer temperature changes. I found the Mann et al, 2008, Proxy-based reconstructions of hemispheric and global surface temperature variations over the past two millennia paper to contain thoughtful analysis and full of interesting observations. This rather fresh paper (Jesper et al, 2009, Trends and uncertainties in Siberian indicators of 20th century warming) even argues that there is no divergence problem when long term trends are carefully preserved. But there are many more, e.g. Briffa et al. 1998a, 2001, 2002a, 2004. One could go on and on about the divergence problem. So, it's clear that the divergence has been widely discussed in the literature and the papers describe the possible impacts on reconstructions and the basis on which the decision is made to truncate at 1960 instead of leaving the affected proxies out completely. A number of these papers have already been mentioned earlier in this thread and other linked threads, Google Scholar gives access to loads of relevant literature and multiple posters before have tried to point KL to relevant literature. Yet KL still insists not knowing the reasons underlying the decisions. Why, KL, if you care about this, don't you make the effort to educate yourself and read some of the articles presented to you instead of ignoring them and simply piling on more noise in the next post? KL also writes: As far as CRU 'losing' the raw data [..] If I recall correctly, Jones' "lost data" issue was about CRU's local copy of direct temperature readings maintained by other institutes and not about proxy data. It has nothing to do with this topic on proxies... Maybe you conflated those issues with McIntyre's Yamal proxy data which he had for all long time already while still complaining that Jones wouldn't give that same data to him? Although offtopic, it is worth noting that KL is also a bit inaccurate about the time period in which CRU did not backup their original temperature readings. The following quote is from CRU's website: We are not in a position to supply data for a particular country not covered by the example agreements referred to earlier, as we have never had sufficient resources to keep track of the exact source of each individual monthly value. Since the 1980s, we have merged the data we have received into existing series or begun new ones, so it is impossible to say if all stations within a particular country or if all of an individual record should be freely available. Data storage availability in the 1980s meant that we were not able to keep the multiple sources for some sites, only the station series after adjustment for homogeneity issues. We, therefore, do not hold the original raw data but only the value-added (i.e. quality controlled and homogenized) data. Perhaps you can remember how much data storage did cost in the 1980's, KL?
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  41. Cynicus @92, Thanks for taking the trouble to address KL's misinformation and his misunderstandings. Not sure why KL suddenly moved the goal posts shifted to losing the global surface temperature data. Anyhow, that accusation is just another red herring. Jones was not even in charge of CRU in the eighties when their copy of the surface data were lost. This is my understanding of what happened. The CRU copy of the temperature data seems to have been lost when they moved offices several times back in the 1980s. No global surface temperature data has been lost, the original owners or proprietor of those data still have those data. And CRU now probably once again has a copy of the temperature data. If people are going to make serious accusations it sure would help, and add to their credibility, if they were to first take the trouble to do some of their own research, rather than parroting myths from contrarian sites or blogs.
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  42. cynicus #92 A thoughtful and detailed comment cynicus. I started running computers in my business in 1981. 8" floppies and Winchester HDD existed which I would suggest would easily have held all the time series temperature data CRU worked with in that era right up to the present. A station, date, time and temperature in simple format would occupy a very small amount of electronic space. 5" floppies could hold 1.2MB (from memory). A large piece of software in the late 1980's would load from 6 x 5" floppies. I did not say that CRU lost data on the proxies. "No global surface temperature data has been lost, the original owners or proprietor of those data still have those data. And CRU now probably once again has a copy of the temperature data" I thought Jones was quoted as saying that they did not have the resources to reconstruct that data. Nothing about 'once again has a copy'. Has it been confirmed that someobody else had a copy which could be restored to CRU?? If no, what this means is that someone has to re-assemble all the data from the 'original proprietors or sources' which would be national weather services etc. I would have thought that was a pretty big job. The AGW case argues that massive changes to global energy use is urgently required. This involves huge economic and political challenge for all countries. You are arguing that key raw data upon which this case was constructed was lost due to 'moving offices'. I can read Captain Cook's 'raw' log from his voyage of discovery of Australia (1769-70), Darwin's 'raw' account of the voyage of the Beagle, Elizabeth 1's 'raw' latin lessons and letters to her father - but not Phil Jones' 'raw' data from 25 years ago. Hello??
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  43. KL #94 #90 I see you're still exclusively interested in the temperature/heat data. It is possible to take the analysis from a different viewpoint. Why don't we look at all non-temperature/heat content data comprising evidence for anthropogenic warming. In this comment I indicated a few variables which are completely 100% independent of the temperature/heat content record which are also evidence for anthropogenic climate change. So the way to test your hypotheses that the temperature record is unreliable, and that the OHC/TOA data contradicts the theory of anthrpogenic warming) is to ascertain whether these independent lines of evidence contradict the temperature data provide support for your hypothesis. I strongly suspect that they do not. This way we dodge the uncertainties inherrent in the various temperature/heat content records, but still retain a rigorous approach to understanding the evidence. At the moment your analysis lacks sufficient rigour.
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  44. @KL: "The AGW case argues that massive changes to global energy use is urgently required. This involves huge economic and political challenge for all countries." Actually, transitioning away from fossil fuels is not only an imperative from the point of view of AGW theory (which you have yet to successfully challenge in all these months spent here), but it is also a strategic necessity. Oh, and AGW theory isn't based on lost data, but on sound, verified science. The fact that the original, non-normalized data (still available from national weather services) is or isn't in CRU's possession is completely irrelevant. It's a red herring, just like pretty much your entire contribution to this site. One year later, it's clear to anyone who knows anything about the science that Climategate was a fake scandal. The fact that it has pretty much disappeared from public consciousness - replaced by damning ties between climate denialist billionnaires and the Tea Party - is clear testimony that this particular act of disinformation by unscrupulous political activists has been relegated to the dustbin of history.
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  45. A reminder to those floating red herrings about alleged lost data: "No off topic comments. Stick to the subject at hand. If you have something to say about an unrelated topic, use the Search form in the left margin to find the appropriate page."
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  46. archiesteel #96 "Oh, and AGW theory isn't based on lost data, but on sound, verified science. The fact that the original, non-normalized data (still available from national weather services) is or isn't in CRU's possession is completely irrelevant. It's a red herring, just like pretty much your entire contribution to this site." The topic of this thread is Climategate - hiding the decline. Hiding the delcine relates to the treatment by CRU's Jones of tree ring temperature proxies which were spliced with thermometer data after 1960 - when the proxy no longer matched the warming trend. All the raw global thermometer data was collected and many (if not all) 'corrected' by CRU to produce the surface temp series HADCRUT etc. As even kdkd says ""Even if we take the idea that the "Nature trick" was dodgy...", indeed we surely can ask for an independent verification of the CRU 'corrections' to the raw surface temperature data - by simply asking CRU for a copy of the raw data. Unfortunately CRU 'lost' this raw input data Of course it has has the output with a description of how it was processed in the literature somewhere going back in time. In plain language - do dodgy once and don't be surprised if others want to look at your other 'tricks' to verify there is no other 'dodginess'. Archiesteel - I can't remember which thread I last conversed with you but your ungenerous remark does not fit with my recollection of the weakness of your contribution.
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  47. KL #98 Oh for goodness sake. I pointed out a method by which you could evaluate the importance of anthropogenic warming with using all the questionable high uncertainty measurements to one side, or as secondary data. But as your ideologically motivated argument relies on magnifying this uncertainty out of all proportion to its importance, you refuse to look at anything except a very small part of the temperature record. Very poor methods there, you've really got to try a lot harder. Very poor indeed.
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  48. @KL: "The topic of this thread is Climategate - hiding the decline." Actually, the true topic is how that innocuous phrase was misrepresented by climate "skeptics" - something which you continue to do to this day it seems, even though no one seriously believe there was anything misleading or dishonest about the phrase in its proper context. "All the raw global thermometer data was collected and many (if not all) 'corrected' by CRU to produce the surface temp series HADCRUT etc." Please provide actual evidence that the corrections to the data made it less represenative of reality. If you do not have any evidence of this, then you are making baseless accusations, which is not a logically tenable position. "In plain language - do dodgy once and don't be surprised if others want to look at your other 'tricks' to verify there is no other 'dodginess'." Except there was no dodginess in the first place. "when the proxy no longer matched the warming trend" Indeed, because tree ring proxies since the 1950s do not accurately represent actual temperatures. The misleading thing would have been to *continue* using the proxies past this date. "Archiesteel - I can't remember which thread I last conversed with you but your ungenerous remark does not fit with my recollection of the weakness of your contribution." At least my contributions make sense, and are not a series of confused deductions based on erroneous premises. So say my contributions are weak all you want, they are the rock of Gibraltar compared to yours. (Nor do I constantly whine about being "censored" when my comments are redacted due to inflammatory language. Instead, I take it like a responsible adult. You should try it. This is just a website, after all - it's not as if we're being paid to post here, right?) "The argument then goes - if one bit of this 'science' is dodgy - how do we know that the rest is rock solid" Uh, by analyzing it? I mean, that is the logical thing to do. On the other hand, if we were to apply your logic to professional climate deniers like Singer, Lindzen, Watts and McIntyre - who have been shown to be wrong over and over again - then none of them should have *any* credibility left, and you should criticize them as much as you do actual climate scientists.
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  49. archiesteel #100 "Uh, by analyzing it? I mean, that is the logical thing to do. On the other hand, if we were to apply your logic to professional climate deniers like Singer, Lindzen, Watts and McIntyre - who have been shown to be wrong over and over again - then none of them should have *any* credibility left, and you should criticize them as much as you do actual climate scientists." Thats exactly what we are doing here - analysing the science as 'modestly informed' non-expert professionals. I don't rely on Singer, Lindzen, Watts or McIntyre for information - although I have read some of their stuff it is not for some time. In fact I have not looked at WUWT for months. There is more than enough grist to be milled in these threads. It is much more satisfying examining the AGW (via CO2GHG) protagonists arguments and seeing if they are internally consistent and fit with other AGW data. I have never claimed that they had no case - but that the case is more or less exaggerated.
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  50. @KL: " I have never claimed that they had no case - but that the case is more or less exaggerated." Yes, and you have been unable to demonstrate any such exaggeration. It's clear you are here for political reasons, i.e. to continue to muddy the waters and delay any action on AGW. In fact, it took me about 5 minutes to figure this out the first time I read one of your posts...
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