NAS Panel deja vu

I wrote earlier about McIntyre’s attack on the NAS Panel on temperature reconstructions. McIntyre objected to two panelists because they were co-authors of co-authors of Mann, but not to the panelist who was a co-author of a co-author of McKitrick. In another post he also objects to another panelist, Kurt Cuffey, because Cuffey wrote:

Mounting evidence has forced an end to any serious scientific debate on whether humans are causing global warming. This is an event of historical significance, but one obscured from public view by the arcane technical literature and the noise generated by perpetual partisans.

McIntyre claims that this demonstrates prejudice, but Cuffey does not include the Hockey Stick as one of the pieces of mounting evidence. The only thing that Cuffey writes about temperature reconstructions is this:

Reconstructions of past climates, on timescales of millennia to millions of years, demonstrate that small changes in climate influences (like greenhouse gases) cause significant climate changes. And the magnitude of the changes is in the mid- to high range of predictions from the best climate models (published October 2004).

Obviously he’s not referring to the Hockey Stick, which shows little change in temperature before the 20th century.

However, it could be argued that one of the panellists has made up his mind about the Hockey Stick. That panelist is John Christy who reckons that the Hockey Stick was broken by Soon and Baliunas:

The conclusion in IPCC 2001 that human induced global warming was clearly evident was partly based on a depiction of the Northern Hemisphere temperature since 1000 A.D. This depiction showed little change until about 1850, then contains a sharp upward rise, suggesting that recent warming was dramatic and linked to human effects.[3] Since IPCC 2001, two important papers have shown something else.[4] Using a wider range of information from new sources these studies now indicate large temperature swings have been common in the past 1000 years and that temperatures warmer than today’s were common in 50-year periods about 1000 years ago. These studies suggest that the climate we see today is not unusual at all.

McIntyre, of course, makes no objection to Christy’s presence on the panel.

McIntyre is also unhappy with another panelist

[Bloomfield] is cited in two pers. comms. in Briffa et al [Holocene 2002] where Briffa describes how they went about estimating confidence intervals for their MXD reconstruction – you know, the one where they chop off the period after 1960. Out of all the statisticians in the world, why would they pick one who consulted on confidence intervals for one of the Hockey Team studies?

Ummm, because he knows something about the statistics of reconstructions?

I’ve seen all this before. Back in 2001, John Lott made similarly specious attacks on the NAS panel on firearms research, claiming that it was biased. You see, there is nothing to lose in making such criticisms. If the panel comes down against you, you can dismiss their findings as biased (this is what Lott ended up doing). And if they come down on your side, you can present their findings with: “Even though they were biased against me …”

Update: John Fleck finds a coauthorship chain connecting McIntyre with Mann: McIntyre – McKitrick – Michaels – Christy – Pielke Senior – Mann. OK, Lambert – Stanton – Stinson – Erdos.

Comments

  1. #1 Dennis Williams
    February 27, 2006

    As a completely impartial observer, there’s a couple of opinions I’ve formed about Lambert and McIntyre.

    1) Lambert absolutely hates the fact that McIntyre is basically a decent straightforward kind of guy (whether McIntyre’s one man crusade will get anywhere is another story). Lambert secretly wishes, of course, that McIntyre was some oil company shill; ‘twould make things so much easier

    2) Ol’ Tim, like your typical McIntyre detractor, and as I’ve pointed out on this blog before, cannot offer any refutation(zero, zip, zilch) of McIntrye’s technical arguments, which of course leads Lambert to post banal drivel like this.

    …and I’m sure the introduction of Lott into this argument must represent about 5 logical fallacies.

  2. #2 Dano
    February 27, 2006

    The earth is warming. Ecosystems are changing at rates not seen before according to our current understanding. This is not in dispute.

    The levels of CO2 in the atmosphere mean that comparisons to past climates are invalid. Denialists can’t explain why we wouldn’t expect the earth to warm when we inject CO2 into the atm – they have no models or theories of their own – all they have is a terrible two-like ‘Nnnnno!’

    Fortunately, decision-makers get it (they usu. don’t listen to ignoramuses) and are beginning to ask the questions on how to take steps to mitigate change (how do we get water? Where will we grow crops? What will power transportation? What sector do we cut oil out of so we can have a soft landing?) and to avoid future issues (how do we shift investment to new sectors? Where will environmental refugees go and how will that effect native populations?).

    The impetus for action is too great to wait for pouty little foot-stamping denialists to be satisified (which is likely never, as there is always something to quibble about).

    Best,

    D

  3. #3 Spence_UK
    February 27, 2006

    Re #1

    Great call, Dennis. I fully concur with your views, although I cannot make the same claim of being an impartial observer.

    There is an important distinction in how the NAS policy is worded that is not described here. The policy specifically states that biases should not be disqualifying, unless the person “is totally committed to a particular point of view and unwilling, or reasonably perceived to be unwilling, to consider other perspectives or relevant evidence to the contrary”.

    So bias and scepticism is acceptable, but being closed minded is unacceptable – what a refreshingly scientific approach!

    Note Christy uses words like “suggests” above when drawing conclusions; indicating a willingness to change his views as new information comes in. Cuffey uses words like “buried” and “debate ended”. These are subtle, but important differences in the context of the NAS policy; even if Cuffey’s remarks were on a wider (but related) topic.

  4. #4 Tim Lambert
    February 27, 2006

    Dennis, your claim to be completely impartial would be more plausible if you hadn’t previously stated that you believed that McIntyre had debunked the Hockey Stick. You haven’t actually addressed any of the points I raised in my post. Nor are you any good at reading my mind.

  5. #5 James
    February 27, 2006

    Tim,

    Cuffey refers to reconstructions of millinial scale – what else could these be other than the hockystick/spaghetti graph reconstructions? I would read this as explicitly including the hockeystick – minimal climate variability until anthropogenic GHGs arrived.

    And taking up Dennis’ point, when have you written a single sentence tackling McIntyre’s statistical work?

  6. #6 Tim Lambert
    February 27, 2006

    James, the evidence for AGW that Cuffey is citing is that there HASN’T been minimal climate variability. Which is the opposite of the Hockey Stick.

    When has McIntyre written a single sentence tackling the statistics in any of my posts?

  7. #7 Steve
    February 27, 2006

    “And taking up Dennis’ point, when have you written a single sentence tackling McIntyre’s statistical work?”

    Tim, tell the one again about when you identified that M&M confused degrees with radians and the degrees McKitrick one too. they were funny!

  8. #8 Ken Miles
    February 27, 2006

    Cuffey refers to reconstructions of millinial scale – what else could these be other than the hockystick/spaghetti graph reconstructions? I would read this as explicitly including the hockeystick – minimal climate variability until anthropogenic GHGs arrived.

    Cuffey is probably referring to Von Storch’s finding that the hockeystick underestimates variability and the perspectives article which was published in the same issue of science (Oct 2004).

  9. #9 Ken Miles
    February 27, 2006

    Steve – different M&M. Not McIntyre.

  10. #10 John Cross
    February 27, 2006

    James. I am not sure of your point. Cuffey has made statements about anthropogenic global warming however if you read the project scope of the NAS it says:

    The committee will address tasks such as identifying the variables for which proxy records have been employed, describing the proxy records that have been used to reconstruct surface temperature records for the pre-instrumental period, assessing the methods employed to combine multiple proxy data to develop surface temperature reconstructions, discussing the geographical regions over which proxy data can be reliably extrapolated, and evaluating the overall accuracy and precision of such reconstructions.

    There is nothing there about anthropogenic global warming what-so-ever. However Cuffey does have expertise in the area of using oxygen isotopes in regards to temperature reconstructions and thus in my opinion he should have a place on the committee.

    Spence: You state that “Note Christy uses words like “suggests” above when drawing conclusions; indicating a willingness to change his views as new information comes in.”

    I would like to point out that Christy also said “This depiction showed little change until about 1850, then contains a sharp upward rise, suggesting that recent warming was dramatic and linked to human effects.[3] Since IPCC 2001, two important papers have shown something else.[4] “ emphasis added.

    That is a fairly definite statement and his conclusion based on two papers is not that they suggest or imply that the hockey stick was wrong but actually show it. That seems like a fairly closed minded statement to me.

    Regards,
    John

  11. #11 Chris O'Neill
    February 27, 2006

    From Dennis Williams:

    “As a completely impartial observer,”

    love the irony.

  12. #12 Scott Church
    February 28, 2006

    Dennis Williams,
    “Lambert secretly wishes, of course, that McIntyre was some oil company shill; ‘twould make things so much easier’”
    He is an oil company shill Dennis! McIntyre consults for the Marshall Institute which is one of the most important anti-climate change astroturf organizations in the world and heavily funded by the fossil fuel industry. According to the institute’s web site, their Chief Executive Officer William O’Keefe was Executive Vice President and Chief Operating Officer of the American Petroleum Institute, on the Board of Directors of the Competitive Enterprise Institute and Chairman Emeritus of the Global Climate Coalition–all major fossil fuel industry funded astroturf groups. Among other major contributors the institute is heavily funded by Exxon Mobil, who has given them some $515,000 total since 1998 (for instance, see Exxon’s corporate funding reports for 2003 and 2004). McIntyre writes for them. He is also a strategic advisor for CGX Energy, another oil and gas exploration company.
    So yes, as a matter of fact this does make it much easier to demonstrate his motives for producing pseudoscience.
    “Ol’ Tim, like your typical McIntyre detractor, and as I’ve pointed out on this blog before, cannot offer any refutation (zero, zip, zilch) of McIntrye’s technical arguments, which of course leads Lambert to post banal drivel like this.”
    Tim has addressed McIntyre’s pseudoscience at length in several places including this post, this post where he discusses a paper of Ross McKitrick’s that drew heavily from McIntyre’s work, and this one where he discusses the McKitrick & McIntyre paper directly. These directly reference relevant peer-reviewed science and/or works that are based on it and well cited. McIntyre’s misdirected efforts have also been addressed in numerous other places as well (for instance, here, here, and here. Is this your idea of “zero, zip, zilch”?
    You claim to be “a completely impartial observer”, but the stridency of your remarks and your carelessness in fact-checking prove otherwise.

  13. #13 James
    February 28, 2006

    Scott Church,

    Your accusation that McIntyre is an industry shill is a serious one, and you better back it up. None of your links demostrate your assertion in any way.

  14. #14 James
    February 28, 2006

    Tim,

    “James, the evidence for AGW that Cuffey is citing is that there HASN’T been minimal climate variability. Which is the opposite of the Hockey Stick.”

    Well unless I’m in some sort of looking-glass world, I thought that MBH purported to demonstrate that there was minimal climate variablity (on a millenial scale) until the 20th century. So, are you suggesting that Cuffey is an anti-HS guy? And/or is he disregarding the paleo stuff?

    And again I’ll ask, do you have any explicit criticisms of McIntyres work?

  15. #15 James
    February 28, 2006

    Scott Church,

    The links you provide do not lay a glove on McIntyre. Why don’t you post what you think are the meaningful paragraphs, and we can have a chat about them?

  16. #16 Scott Church
    February 28, 2006

    James,
    I beg to differ. Every one of my links regarding McIntyre’s affiliations with the fossil fuel industry either speak directly about him or an organization he is associated with. The first one is to his actual bio at the Marshall Institute site, and my links regarding that association’s affiliations clearly demonstrate the institute’s ties to the fossil fuel industry. The Marshall Institute is specifically mentioned in the Exxon Mobil funding reports I linked for 2003 and 2004 (do a PDF search of the documents for “Marshall”). My link to the 2003 Annual report of oil and gas exploration firm CGX Energy specifically refers to McIntyre as a “strategic advisor” and even states that Northwest Exploration Company Limited, where McIntyre was President, was CGX’s predecessor company (again, do a PDF Search of the document for “McIntyre”).
    All of this was in response to Dennis Williams’ erroneous claim that McIntyre has no ties to big oil, and each link is directly relevant.
    As for the links I provided to Tim’s posts, all either speak directly to McIntyre’s pseudoscience or to work by his colleague Ross McKitrick that made references to McIntyre and drew at least indirectly from his work. The external references to Realclimate address the McKitrick and McIntyre hockey stick paper. In the first one their misrepresentations of the original Mann et al. paper are discussed along with various bogus claims they made regarding the use of Principle Component Analysis in the hockey stick derivation (see the “Myth 4″ section). That paper also links other rebuttals and peer-reviewed research that bears directly on falsehoods in McIntyre’s claims, including a reference to an upcoming paper by Rutherford et al. in Journal of Climate that has since been published. The second one goes into much more detail about the nature of PCA and how McIntyre and McKitrick misrepresent it for their own purposes. The Mann et al. paper I linked is a direct rebuttal of McIntyre and Mckitrick as well.
    I fail to see how all of this “doesn’t lay a glove” on McIntyre. It clearly demonstrates both his bias, and his lack of understanding of the science involved.

  17. #17 James
    February 28, 2006

    Sott,

    You have to be kidding? Just because ther Marshall Institute carries a reference to McIntyre’s bio, he’s an indistry shill? Get real.

    How about, instead of linking to alleged rebuttals at realclimate, you post your actual objections to McIntyre’s work right here, and we can duke it out?

    Same challenge applies to Tim, who has so far dodged this request.

    Sheesh.

  18. #18 Chris O'Neill
    February 28, 2006

    According to James:

    “Scott Church, The links you provide do not lay a glove on McIntyre.”

    This wouldn’t be the same James (i.e. Lane) who couldn’t find the quote “In other words, using correct PC methodology, how much does the large-scale hockey-stick shape change if the bristlecone pine data are excluded?” on the page http://www.realclimate.org/index.php?p=128 when advised on John Quiggin’s blog that this is one place where Mann had made an answer to his question? If so then there is no surprise that he can’t find a glove laid on McIntyre.

    There is further material regarding McIntyre’s mistakes at False Claims by McIntyre and McKitrick regarding the Mann et al. (1998) reconstruction
    and at On Yet Another False Claim by McIntyre and McKitrick .

  19. #19 Scott Church
    February 28, 2006

    James,
    It was not a “reference”. It was a bio detailing McIntyre’s role as a hired consultant at the Marshall Institute, which in point of fact is a world class hack astroturf front group. Yes James, this absolutely does make him an industry shill. If it doesn’t, please tell us what would.
    My “alleged rebuttals at Realclimate” were quite specific regarding McIntyre’s claim that the 20th centurt global average temperature rise in the MBH98 reconstruction (the hockey stick) was an artifact of the use of Principle Component Analysis with infilled data and the convention by which certain networks of proxy data were included. Both articles were fully cited on these points including (to name just a few);
    Cook, E.R., J. Esper, and R.D. D’Arrigo, Extra-tropical Northern Hemisphere land temperature variability over the past 1000 years, Quat. Sci. Rev., 23, 2063-2074, 2004.
    Esper, J., E.R. Cook and F.H. Schweingruber, Low-frequency signals in long tree-line chronologies for reconstructing past temperature variability, Science, 295, 2250-2253, 2002.
    Jones, P.D., K.R. Briffa, T.P. Barnett and S.F.B. Tett, High-resolution palaeoclimatic records for the last millennium: Integration, interpretation and comparison with General Circulation Model control run temperatures, Holocene, 8, 455-471, 1998.
    Jones, P.D., Mann, M.E., Climate Over Past Millennia, Reviews of Geophysics, 42, RG2002, doi: 10.1029/2003RG000143, 2004.
    Mann, M.E., R.S. Bradley, and M.K. Hughes, Global-scale temperature patterns and climate forcing over the past six centuries, Nature, 392, 779-787, 1998.
    Mann, M.E., R.S. Bradley, and M.K. Hughes, Northern Hemisphere Temperatures During the Past Millennium: Inferences, Uncertainties, and Limitations, Geophysical Research Letters, 26, 759-762,
    1999.
    Mann, M.E., Ammann, C.M., Bradley, R.S., Briffa, K.R., Crowley, T.J., Hughes, M.K., Jones, P.D., Oppenheimer, M., Osborn, T.J., Overpeck, J.T., Rutherford, S., Trenberth, K.E., Wigley, T.M.L., On Past Temperatures and Anomalous Late 20th Century Warmth, Eos, 84, 256-258, 2003.
    Rutherford, S., Mann, M.E., Osborn, T.J., Bradley, R.S., Briffa, K.R., Hughes, M.K., Jones, P.D., Proxy-based Northern Hemisphere Surface Temperature Reconstructions: Sensitivity to Methodology, Predictor Network, Target Season and Target Domain, Journal of Climate, in press, 2004.
    Moberg, A., DM. Sonechkin, K Holmgren, NM Datsenko, & W Karlin. Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data. (doi:10.1038/nature03265).
    Realclimate also has another “alleged rebuttal” of McIntyre’s pseudoscientific hockey stick criticisms, another one here (including supplemental PCA data here), this article on the Moberg et al. reconstruction (which by the way, independently confirms the hockey stick effect using methods very different from those of Mann et al., and for which McIntyre’s criticisms would be irrelevant to even if they were correct), and this one which discusses the hockey stick in general. Again, all cited to the peer-reviewed science.
    Post my “actual objections” you say? I linked these posts precisely because they do in fact contain my specific objections to McIntyre’s work, and they’re cited directly to his publications on each point as well as those of his colleagues Willie Soon, Sallie Baliunas, and Ross McKitrick–all industry shills as well.
    As for my reliance on “alleged rebuttals at Realclimate”, I’ve got news for you James. It doesn’t get more relevant than the published peer-reviewed science on the subject!.
    I’m afraid I haven’t the time to “duke it out” with you until you’ve read what’s already been provided to you.

  20. #20 Tim Curtin
    February 28, 2006

    Perhaps we could broaden the argument a bit?

    The tree-ring proxies for temperature relied on by Osborne & Briffa in their Science article this month assume that there is a POSITIVE correlation between tree rings and temperature, such that

    y(t) = a + x(t) …….(1)

    where y is the predicted temperature, and x is the “regional growing season temperature” from the “predictor” (i.e. tree rings) (equation from Briffa et al, 2002).

    But in reality tree ring widths are the result of several factors, including site slope and orientation, soils, temperature and – above all – precipitation. Recently derived tree ring data from Bighorn Basin shows that there, tree rings (x) are positively correlated (over 100 years to 1995) with precipitation, and NEGATIVELY with temperature, so that we have

    x(t) = a – y(t) + z(t)…..+ u(t) …..(2)

    where z denotes precipitation and u all the other factors ignored by Briffa & co.

    Thus Briffa’s equation should read:

    . y(t) = a – x(t) +z(t) ….+u(t) …..(3)

    So am I right that tree rings are hardly a valid proxy, being evidently based on bogus correlations that became possible only because precipitation was ignored? If so, the MBH hockey stick and the arguments over its existence become irrelevant, for it may well be there is NO aggregate evidence that tree rings taken together constitute a valid proxy for temperature now or in the past (Osborne and Briffa 2005 could only find ten or so tree ring series that had any correlation at all with temperature, with average correlations of less than 0.5). BTW, the Bighorn Basin tree rings were cut in Wyoming as recently as 1998, although apparently Mann claims it has been “too difficult” for any new tree rings to have been cut since the 1970s. My source asks not to be cited as this data is pre-publication but clearly explosive, which may explain why Science for example is unlikely ever to publish it.

  21. #21 Tim Lambert
    February 28, 2006

    No, Tim Curtin, the proxies don’t assume that. Try reading some the links that Scott posted.

  22. #22 Tim Curtin
    February 28, 2006

    Thanks Tim Lambert for the arm waving but could you be more specific?

  23. #23 Jack Lacton
    February 28, 2006

    Gee, the ad hominem attacks are getting worse, which means that the ‘anti’ brigade are losing the argument.

    Steve McIntyre has done some of the most important work on exposing climate change fraud over the last year than anyone. The Realclimate ‘rebuttals’ Scott refers to, among other references, are absurd and fail to refute any of his claims. He has come out of left field for the Hockey Stick Team and demonstrated beyond any doubt that the series formed by them are statistically unsound. Beyond any doubt if you did high school stats, that is.

    However, don’t panic, pro-AGW believers, as the NAS panel will make sure that it doesn’t upset the government funded apple cart that many of its members are benefiting from.

  24. #24 Spence_UK
    February 28, 2006

    John C.

    Thanks for your thoughtful reply to my post.

    The section of Christy’s statement you highlight is referring to the content of a paper, rather than his own opinion. It is entirely reasonable to say “Paper X has shown A, but paper Y has shown not A”, as the statements are limited in scope to the papers themselves. But when Christy draws a broader conclusion, reflecting his opinion, he keeps it open ended.

    That said, I want to avoid microscopic analysis of everything these people have said in the past. I suspect madness lies that way ;) The key point from my post is that this topic has made certain assumptions (e.g. that bias should disqualify panellists) which are not in line with stated NAS policy.

    There is also another point (perhaps not appropriate here!) over whether the NAS policy is a good one. I think it has some problems; but that is the policy they have in place, so that is what they should adhere to.

  25. #25 John Cross
    February 28, 2006

    Spence, I think that I agree with you!! I agree that bias on a topic should not exclude participants. I am happy with the composition of the NAS Committee and feel that both Cuffey and Spencer will add to it.

    I also agree that we should avoid microscopic analysis of what was said. For example I could argue that Christy did not say that Paper X shows this and Paper Y shows that. Instead he held a view based on two papers that they were right and the opposing point was wrong. But one might accuse me of being mad to make such a fine point and – depending on the phase of the moon – I might even agree.

    Regards,
    John

  26. #26 Spence_UK
    February 28, 2006

    Thanks John.

    Now, in the long held blogosphere tradition, we must trade insults :-) En garde!

    Seriously though, because the field of paleoclimatology is so small I don’t think you can fully avoid conflicts of interest etc. So the NAS policy reflects an unachievable ideal in this case. My preference would be to change the policy in this respect to declare conflicts of interest and maintain a balance through transparency, rather than a belief that there is such a thing as a perfect committee.

    My one criticism of the panel as it stands would be to have an independent statistician as well as the expert statisticians in the field of research. (i.e. add one person, but take no-one away) Statistics is a funny game and sometimes people in the field are too close to the coal face to ask the right questions.

  27. #27 z
    February 28, 2006

    “Stephen McIntyre has worked in mineral exploration for 30 years”

    Imagine the kerfuffle had it read “Stephen McIntyre has worked in environmental protection regulation for 30 years”.

    See also the various references to the Association of Petroleum Geologists (in terms of awarding Crichton’s book as a science book) as just “scientists”.

  28. #28 Chris O'Neill
    February 28, 2006

    Two things that amaze me even if McIntyre’s reconstruction is correct are

    1. McIntyre’s reconstruction tries to suggest that the medieval warming period didn’t end until well into the 15th century. According to Lamb, in his 1965 study of the evidence for the medieval warming period, “[M]ultifarious evidence of a meteorological nature from historical records, as well as archaeological, botanical and glaciological evidence in various parts of the world from the Arctic to New Zealand . . . has been found to suggest a warmer epoch lasting several centuries between about A.D. 900 or 1000 and about 1200 or 1300.”

    McIntyre would have us believe that Lamb was wrong by 200 years.

    2. McIntyre’s reconstruction completely ignores temperatures since 1980 which are now nearly 0.5 degrees C warmer than 1980 which itself was warmer than the years immediately preceeding it. If his reconstruction had not ignored these years it would have been clear that MBH98′s original conclusion “Northern Hemisphere mean annual temperatures for three of the past eight years are warmer than any other year since (at least) AD 1400″ was completely unaffected.

    Why was McIntyre not interested in a clear presentation of the evidence?

  29. #29 Dennis Williams
    February 28, 2006

    Scott Church

    McIntyre says(post and comment #35);
    http://www.climateaudit.org/?p=400#more-400

    I’d be curious to hear T.L.’s opinion on this.
    Tim, is McIntyre an oil company shill?

  30. #30 John Cross
    February 28, 2006

    Mr. Williams:

    In your link Mr. McIntyre says … it’s despite explicit statements that I am not being financed by ExxonMobil or anyone else and I am not doing this to save the carbon economy. I?m doing this from my savings and I?m doing this because I find it interesting.

    Now, one of the points that Mr. McIntyre has made time and again is that claims must be substantiated. It is not enough for someone to say something unless they can back it up and the information examined by others.

    So have you seen Mr. McIntyre financial records? How about his tax returns? Without something to back up his claim, how can you put it forward as an argument?

    Regards,
    John

  31. #31 Ken Miles
    February 28, 2006

    I thought that MBH purported to demonstrate that there was minimal climate variablity (on a millenial scale) until the 20th century. So, are you suggesting that Cuffey is an anti-HS guy? And/or is he disregarding the paleo stuff?

    Cuffey cited a study which found that MBH underestimated early climate variability.

  32. #32 Dano
    February 28, 2006

    Yes, by golly – an amateur should audit the financial records and tax returns of people who insist on substantiation. Excellent point John C.

    So, are you suggesting that Cuffey is an anti-HS guy?

    Most people familiar with the issue (and not attempting to obfuscate, hand-wave or mendacicize) recognize that the “shaft” of the “HS” is not straight. The science has moved on. The folks who want to “bring down” the hockey stick are bashing an 8-yr old paper that has been passed by. Not that this information will stop them, but hey.

    Best,

    D

  33. #33 Dano
    February 28, 2006

    whoops. linky

  34. #34 Dennis Williams
    February 28, 2006

    John Cross,

    I’ve eliminated the usual hearsay and innuendo on this subject and presented direct statements from McIntyre and your advice to me is…Just assume that he’s lying. What’s the point of this debate?
    I would suggest that we dismiss our antagonists as liars at our own peril.

  35. #35 James
    February 28, 2006

    Scott,

    I asked you to quote a few paragraphs that allude to McIntyre’s “mistakes” and you reply with a barrage of links to Hocky Team rebuttals. I’ve read all these before. Why don’t you provide your own argument?

    Two questions:

    1) Is MBH98 robust to the presence or absence of the bristlecone pines?

    2) What is the r2 statistic for the 1400 reconstrction in MBH98 (and Ammann et al, since we’ve “moved on”)

    Should be simple enough to answer these two questions. You’ll recall that I sent the first one to realclimate, without an answer (or indeed being posted at all)

  36. #36 Dano
    March 1, 2006

    If I may:

    It is simple:

    1) The lastest paper shows that the general finding is that MPRs are robust to any three proxies being taken out.

    2) It’s in Fig 3 (IIRC – the figger thingy with the grey boxes an’ stuff with r^2 values). It’s low. What’s your point?

    Anyway, did you notice that Murrican decsion-makers are starting to ask folk for input about a regulatin’ system to mitigate fyoocher GHG emissions?

    WOW! you might think. Sheesh, no one is paying any attention to the Hockey Stick at the policy-maker level! Quick! you may say. We need a better disinformation campaign!!!

    *heart*

    *cute smiley*

    *unicorn*

    Best,

    D

  37. #37 Dano
    March 1, 2006

    If I may,

    Dennis:

    I don’t want to speak for John, but I read his comment to say: ‘let’s “audit” and find out’. These audity things are big on some blogs, so it’s probably OK to audit, don’tcha think? After all, some folk are calling for any ol’ person to be able to audit stuff. Why not? Fer sure, code and stuff should be looked at. Data, too.

    Lots of data should be audited, some say.

    Right, Dennis?

    I’m sure you’ll agree.

    Best,

    D

  38. #38 Scott Church
    March 1, 2006

    Dennis,
    “I’ve eliminated the usual hearsay and innuendo on this subject and presented direct statements from McIntyre and your advice to me is…Just assume that he’s lying. What’s the point of this debate?
    I would suggest that we dismiss our antagonists as liars at our own peril.”

    Per the link to Climate Audit you provided above, McIntyre claims that he has made “explicit statements that I am not being financed by ExxonMobil or anyone else…. I am also doing this without any ‘coordination’.” In comment 35 at the same post he states that,
    “I have no appointment or office with the George Marshall Institute, either as a “contributing writer” or otherwise. I have made two presentations in Washington at a meeting room on Capitol Hill in Washington co-sponsored by the George Marshall Institute. My travel expenses were paid, but I did not receive an honorarium or fee for the presentation.”
    He is entitled to deny whatever he wishes, as are you in his support. Nevertheless,
    A)   Unless United Airlines has begun accepting Monopoly money since I last flew, paid travel expenses are compensation.
    B)   As for having “no appointment or office with the George Marshall Institute”, their own web site explicitly says otherwise. Not only does Marshall report that he is one of their contributing writers, they even post his presentations and writings at their web site for public download.
    C)   Likewise, Exxonmobil’s own corporate giving reports for 2003 and 2004 name the Marshall Institute–and therefore its staff as benefactors.
    D)   According to the oil and gas exploration firm CGX Energy, McIntyre is “doing this with their coordination” as one of their strategic advisors. The company’s annual reports to their investors for 2000 and 2001 say likewise.
    You’re right Dennis–you have “eliminated the usual hearsay and innuendo” from this discussion. You’ve documented McIntyre’s denials for us, and it’s straightforward to compare his words with those of his benefactors. If McIntyre feels that lies are being spread regarding his connections with Exxonmobil and the fossil fuel industry, then he needs to sue Exxonmobil for publicly advertizing their support of the astroturf group that employs his services, the Marshall Institute for advertizing his affiliations with them to the world and making his work available at their public web site, and the oil and gas exploration company that employs him as a “strategic advisor”.
    Which brings us right back to what everyone has been saying all along. McIntyre is in fact, an industry shill and has a powerful motive for promulgating the climate change pseudoscience he’s become famous for. If you think otherwise, you’re going to have to do better than this. All the best.

  39. #39 James
    March 1, 2006

    Scott, are you aying that Mcintyre is one of the Marshall Intitute’s staff?

  40. #40 Tim Curtin
    March 1, 2006

    Dano said:

    1) The lastest paper shows that the general finding is that MPRs are robust to any three proxies being taken out…

    Dano: any average of 14 events series is quite likely to be “robust” to any 3 being removed, for that is in the nature of averages. Osborne and Briffa claim that 14 proxies are enough for total coverage of the whole of NH weather for 1200 years, even in Wymoming where the correlation between tree rings is known to be negative and even in the Arctic where there are no tree rings, but O&B can tell us the temperature there in 1066 to at least 2 decimal points (plus or minus 5C like all IPCC predictions).

  41. #41 Ken Miles
    March 1, 2006

    McIntyre is in fact, an industry shill and has a powerful motive for promulgating the climate change pseudoscience he’s become famous for. If you think otherwise, you’re going to have to do better than this.

    I’ve got to (partially) stick up for McIntyre here. Compared with most (all?) of the clowns who make the ranks of global warming skeptics, McIntyre is far and away the best of them. He does publish in peer reviewed journals (not just Energy & Environment) and he has raised some genuine concerns (such as access to data – I’m staying away from the more technical arguments as I don’t know enough to judge).

    He does tend to overplay his hand a bit, and climateaudit is a cesspool of idiots, but still credit should be given where it’s due.

  42. #42 Ken Miles
    March 1, 2006

    Scott, are you aying that Mcintyre is one of the Marshall Intitute’s staff?

    It seems pretty obvious that Scott isn’t saying that. Just that he is affiliated with the Marshall Institute and derives some compensation (such as travel expenses) from them.

  43. #43 Chris O'Neill
    March 1, 2006

    Even if McIntyre’s temperature reconstruction from AD 1400 to 1980 is correct, one thing he always fails to show is the temperatures from the instrument record after 1980 which have risen nearly 0.5 degrees C. If he had included these in his reconstruction it would have been clear that MBH98‘s conclusion that “Northern Hemisphere mean annual temperatures for three of the past eight years are warmer than any other year since (at least) AD 1400″ was still true.

    The question is, why doesn’t McIntyre ever show temperatures after 1980?

    Another problem with McIntyre’s temperature reconstruction is that it shows the medieval warm period ending well into the 15th century. Lamb, in his 1965 study, said “[M]ultifarious evidence of a meteorological nature from historical records, as well as archaeological, botanical and glaciological evidence in various parts of the world from the Arctic to New Zealand . . . has been found to suggest a warmer epoch lasting several centuries between about A.D. 900 or 1000 and about 1200 or 1300.”

    McIntyre would have us believe that the medieval warming period actually ended 200 years later than previously believed.

  44. #44 nanny_govt_sucks
    March 1, 2006

    “Even if McIntyre’s temperature reconstruction …”

    If you believe that McIntyre has actually done his own multi-proxy temperature reconstruction, then you don’t understand McIntyre’s work at all.

  45. #45 James
    March 1, 2006

    Oh, come on, Chris.

    McIntyre has never proposed a reconstruction of any sort. That’s one of Mann et al’s canards. You have shot yourself in the foot with this one.

  46. #46 Scott Church
    March 1, 2006

    Ken and James,
    “I’ve got to (partially) stick up for McIntyre here. Compared with most (all?) of the clowns who make the ranks of global warming skeptics, McIntyre is far and away the best of them.”
    “Scott, are you saying that Mcintyre is one of the Marshall Intitute’s staff?”
    I agree Ken. Though I consider McIntyre to be an “industry shill” I do concur that he’s a far sight more respectable than the worst of them. And James, while the Marshall web site does not report him as being “staff” in the sense of being a salaried employee (I used the term a little loosely in my last post), they do report him as being affiliated with the institute and he does receive some level of remuneration for his services. Marshall states that they rely on his contributions to advance their agendas, and Exxonmobil funds them precisely because they benefit from them. McIntyre himself concedes that Marshall has received some $500,000 from Exxonmobil, and this figure agrees well with the figure of $515,000 since 1998 cited by Exxonsecrets.org (cited there to Exxonmobil’s own financial reports to the IRS). It’s a safe bet that Exxonmobil has not sunk over half a million into Marshall solely out of the kindness of their loving hearts! Nor is Marshall proudly advertizing McIntyre and his works at their site when he’s not on their team.
    This does not make McIntyre on the take to nearly the same degree as say, Fred Singer or Pat Michaels, but it is a damn sight further down the industry shill road than “no appointment or office with the George Marshall Institute, either as a contributing writer or otherwise”, and “not being financed by ExxonMobil or anyone else….” All the best.

  47. #47 Tim Curtin
    March 1, 2006

    Ken Miles said (1st March 01.50 am):
    Scott, are you saying that Mcintyre is one of the Marshall Intitute’s staff? It seems pretty obvious that Scott isn’t saying that. Just that he is affiliated with the Marshall Institute and derives some compensation (such as travel expenses) from them.

    Ken,I have news for you: Tim Lambert has been employed for the past ten years by none other than John Howard, chief Kyoto denier in Australia. More than that he has attended conferences at which his presence was most likely also largely funded by said JH. Meantime, apart from biting the hand that feeds him, I notice that he graciously makes himself available to students for 3 hours a week, probably rather less than he spends running this absurd blog. I also note that his publication record apart from said conferences is rather sporadic albeit brilliant in its own way (nut none are related in any way to climate issues). No doubt he will think the above is unfair, but then he has defamed the late Julian Simon for “deceit” on the basis of one incorrect statement in a 700 page book (almost certainly more in just that book than said Tim Lambert has published in his lifetime so far, but he’s a bit coy on the word count in his publication list).

    Joking like the above aside, can we not agree that affilations and funding are less important than the intrinsic worth of what one has to say, whether it be said by Mann, McIntyre, or Lambert?

  48. #48 Chris O'Neill
    March 1, 2006

    In James’ opinion:

    “McIntyre has never proposed a reconstruction of any sort.”

    What’s the problem? Forgotten how to click on a link, McIntyre’s temperature reconstruction from AD 1400 to 1980, the “Recalculated” curve in the graph? There’s also their neighbouring page, “Corrected Version” curve which for reasons I have yet to determine is significantly different from their first page. You can also check out their recontruction in their 2005 Energy and Environment paper (third part of figure 1).

  49. #49 Chris O'Neill
    March 1, 2006

    In James opinion:

    “McIntyre has never proposed a reconstruction of any sort.”

    What’s the problem? Forgotten how to click on a link, McIntyre’s temperature reconstruction from AD 1400 to 1980, the “Recalculated” curve in the graph?

    There’s also his neighbouring page, “Corrected Version” curve which for reasons I have yet to determine is significantly different from the curve on his first page.

    You can also check out his reconstruction in his 2005 Energy and Environment paper (third part of figure 1).

  50. #50 John Cross
    March 1, 2006

    Mr Williams: you said I’ve eliminated the usual hearsay and innuendo on this subject and presented direct statements from McIntyre and your advice to me is…Just assume that he’s lying.

    Well, as Dano, and Mr. Church have said the point is that if you are going to make claims then you should be able to verify them. In fact, I am surprised to hear that you think the opposite and that we should accept the word of researchers without looking at their data.

    Regards,
    John

  51. #51 Tim Lambert
    March 1, 2006

    Tim Curtin, I am employed by UNSW, not John Howard. It says so right on the sidebar so you have no excuse for getting it wrong. If you find the truth about Julian Simon so unpalatable, I suggest you stop reading this blog.

  52. #52 Dano
    March 1, 2006

    nanny_g_s said on 3/1/06 03:04 AM:

    If you believe that McIntyre has actually done his own multi-proxy temperature reconstruction, then you don’t understand McIntyre’s work at all.

    Absolutely! The man has done no work to show the robustness of the denialist hypothesis [increase in atm CO2 has not warmed the planet]. Nor has anyone else. It’s all hearsay.

    The claims of the denialists and contrascientists have no empirical backing.

    Simple, yet complex.

    Best,

    D

  53. #53 Spence_UK
    March 1, 2006

    Chris,

    You’ve misunderstood McIntyre’s point. Mann claimed that his procedure was robust to the removal of dendroclimatic indicators and to the statistical method applied. McIntyre ran the method by removing just one of the dendroclimatic indicators and found the result changed. The graph demonstrates the large change in the result, the graph is not there as an alternative reconstruction.

    This point is important so I’ll repeat it: the graph is not to show an alternate reconstruction, it is to demonstrate the original reconstruction lacks robustness.

    The large change in reconstructed temperature shows that minor adjustments (that should be irrelevant) to the MBH98 algorithm or data produce entirely different reconstructions, therefore the result is not reliable.

    McIntyre is not the only one to make this claim. Burger and Cubasch drew the same conclusion in their later paper (cited below), by applying a different tweaks to the algorithm. You will also note Burger and Cubasch present graphs of temperature in their paper. They also do not claim these are valid reconstructions, they merely present them to show the lack of robustness.

    (Burger, G., and U. Cubasch (2005), “Are multiproxy climate reconstructions
    robust?”, Dec 2005, GRL/32, L23711)

  54. #54 Dano
    March 1, 2006

    1. Why all this fetishization of an original, outdated paper? Do folk in the UK fetishize, say, the Spitfire and insist it should be used in today’s battles?

    2. Why all the focus on just one indicator among scores that show warming of the planet?

    3. How come the fetishizers don’t atomistically scrutinize the CO2 levels in the atmosphere?

    4. Don’t the fetishizers realize the rest of the planet has moved on? Can’t they find something else to atomistically quibble about? Like, say, the information Blair used to mislead his people in war?

    Best,

    D

  55. #55 Tim Curtin
    March 1, 2006

    Tim Lambert – and who funds the UNSW and the leisurely lifestyle it affords if not John Howard’s Commonwealth Government? Your blog supports more deception than you have ever found in Simon, including the continuous slanders against McIntyre.

  56. #56 Spence_UK
    March 1, 2006

    Dano,

    I’m not really interested in engaging in a political debate on a blog, I find they are generally pretty futile. So I’ll avoid most of your overtly political comments. I’m sure there are plenty of other bloggers willing to take you up on that side of the argument; I’d rather stick to the scientific aspects.

    The issues raised in Burger and Cubasch paper are most certainly not out of date, and these issues could well apply to many of the other multi-proxy reconstructions, including some of the most recent ones. Although with everyone keeping their data so close to their chest, just applying these simple tests can be time-consuming. So the implication we are all concentrating on just one old paper is simply false. Paleo climate reconstructions in the scientific literature will go on for a long time yet, and we will learn new things from this.

    Understanding the errors and limitations in Mann et al. will help future reconstructions to be more accurate – that is how science works. Understanding any errors and limitations in McIntyre and McKitrick will help future temperature reconstructions also. But misinterpreting what was written in a paper (as Chris has done above) teaches us nothing.

  57. #57 James
    March 1, 2006

    Dano,

    I asked:

    “2) What is the r2 statistic for the 1400 reconstrction in MBH98 (and Ammann et al, since we’ve “moved on”)”

    You replied:

    “2) It’s in Fig 3 (IIRC – the figger thingy with the grey boxes an’ stuff with r^2 values). It’s low. What’s your point?”

    Fig 3 in MBH98 is for the period 1845-1901. As the “proxies” in this series contain actual instrumental temperature records, it is not surprising that the reconstruction for this period is skillful.

    We know from McIntyre’s emulation that the r2 statistic for the 14th century step is approximately zero, that is, it has no skill, this part of the reconstruction is worthless. We also know from Mann’s source code that he calculated r2 for the earlier stages but did not report the adverse statistic. That is the point.

    But I suspect you already knew that.

  58. #58 John Cross
    March 1, 2006

    Spence: I hate to spoil the fun when we were starting to agree, but I think that a certain amount of “misinterpertation” is understandable. I note that McIntyre is fairly selective about what he corrects and is not above letting the misrepresentation stand.

    That said, I do agree with your last paragraph (at least the first two sentences).

    Regards,
    John

  59. #59 Ken Miles
    March 1, 2006

    Tim C, you get the award for the worst contribution to this thread. Most ad homs, least content. You are doing a fine job however in confirming my prejudices about global warming skeptics.

    PS. Learnt about how temperature scales work yet?

  60. #60 Tim Curtin
    March 1, 2006

    Dano, you said: Don’t the fetishizers realize the rest of the planet has moved on? Can’t they find something else to atomistically quibble about?

    Your link to a proposed bill in the US Senate for a mandatory market-based GHG regulatory system shows a flow chart for GHG in the US that omits any mention of nuclear energy, for the good reason that it omits no GHG. One has to be suspicious of the sincerity of non-sceptics who cannot bring themselves to campaign for adoption of nuclear power as the cheapest and safest way of reducing GHG. AS for safety and storage etc, here’s a hint, from Physics Today, Dec 2003, p.34: “an area the size of a football field is adequate for storing the spent fuel from hundreds of years of a power plant’s operation….”

  61. #61 Spence_UK
    March 1, 2006

    John,

    Hey we were never going to agree on everything!

    I would stress that my comment above does not say misinterpretation does not happen. A certain amount of misinterpretation is inevitable, because language and communication aren’t perfect, and we don’t always get the time we need to analyse scientific papers, etc., in sufficient detail to get the full picture. However I stand by my point that misinterpreting papers rarely teaches us anything (other than perhaps how to be better communicators!) as it simply muddies the water.

    As for letting misinterpretations stand – this is a pretty highly polarised debate, and to be honest I think you just have to accept that each side is only going to point out the mistakes of the other side, and rarely from their own side. Sure it does happen occasionally but it is the exception rather than the rule. I suspect the best you can hope for is that people will back down and admit their own errors when a clear enough argument is presented to them, and there are certainly no shortage of people on both sides of the debate that won’t even do that.

    I hope this post makes sense. It seemed very waffley when I was writing it!

  62. #62 Dano
    March 1, 2006

    We know from McIntyre’s emulation that the r2 statistic for the 14th century step is approximately zero, that is, it has no skill,

    Yes. Like I said the .02 is in the paper somewhere. But,

    It is now 2006. We are not in 1998. 2006. Not 1998.

    2006.

    In 2006, we have ~a dozen or so subsequent MP reconstructions, all of which have greater skill and are used in concert with dozens of utterly different indicators across scores of disciplines that say roughly the same thing.

    That is: there are, literally, piles of other empirical evidence to point to that say roughly the same thing.

    Policy-makers are given executive summaries of the piles of evidence that say roughly the same thing.

    They are not given one chart from 8 years ago. They are given executive summaries of cross-disciplinary empirical findings.

    The majority of them indicate the climate is changing at a likely unprecedented rate.

    So, the point you bring up? It matters not a bit.

    No one cares about that one chart from 8 years ago, inflated by some people to make it seem as if it is the only thing decision-makers see when they are briefed.

    Get it? That constructed narrative has been passed by. Buh-bye. TTFN. Toodles. Ciào!

    So. The thing you’re concentrating on?

    SFW.

    Jus’ sayin’.

    *heart*

    Best,

    D

  63. #63 Dano
    March 1, 2006

    Gosh, thanks Tim Curtin!!!!

    Do you want me to help you find an e-mail addy so you can share your umbrage with our electeds?

    Best,

    D

  64. #64 Chris O'Neill
    March 1, 2006

    According to Spence_UK:

    “You’ve misunderstood McIntyre’s point.”

    Have a look at the third part of figure 1 and read the accompanying text in McIntyre’s 2005 Energy and Environment paper.

    McIntyre’s point was that MBH98′s reconstruction could only be achieved if some particular proxies were included AND if the erroneous choice of principal components used by MBH98 were used. His point was that if you choose his method which he believes is correct (notwithstanding expert mathematicians disagreeing with him) then his result is robust to changes in data. The third part of figure 1 in McIntyre’s 2005 Energy and Environment paper is produced using what he believes is a correct method for producing a reconstruction. If you don’t call something produced by what you believe is a correct method for producing a reconstruction, a reconstruction, then what do you call it?

    In any case, any possible outcome that McIntyre has produced ignores the temperature rise since 1980 so anything he has done does not change MBH98′s conclusion that “Northern Hemisphere mean annual temperatures for three of the past eight years are warmer than any other year since (at least) AD 1400″.

    So the question remains, why doesn’t McIntyre ever show temperatures after 1980?

  65. #65 nanny_govt_sucks
    March 1, 2006

    Chris, I think you’re really off the deep end here. I’ll throw out this life preserver and hopefully we can reel you back in:

    McIntyre is a statistician. He doesn’t do climate reconstructions, he just checks the work of others from a statistical perspective.

    Hope that’s clear.

  66. #66 nanny_govt_sucks
    March 1, 2006

    “If you don’t call something produced by what you believe is a correct method for producing a reconstruction, a reconstruction, then what do you call it?”

    A correction to the MBH98 method, regardless of the veracity of that method.

  67. #67 James
    March 2, 2006

    Dano:

    “Yes. Like I said the .02 is in the paper somewhere.”

    No it’s not, and you know that. Stop lying.

    Many of the problems with MBH generalise to the other multiproxy studies, specifically the selection and worth of proxies. Read Burger and Cubasch.

    Jus’ sayin’.

  68. #68 Chris O'Neill
    March 2, 2006

    I said:

    “If you don’t call something produced by what you believe is a correct method for producing a reconstruction, a reconstruction, then what do you call it?”

    James said:

    “A correction to the MBH98 method, regardless of the veracity of that method.”

    Oh, so no-one produces reconstructions only “methods”. And if roses had a different name they wouldn’t be roses any more. Yeah sure.

    But since the only thing that denialists like James will even consider is the gospel according to McIntyre, here is what McIntyre says in MM05, page 81:

    “The strong negative bias of the two outlier series is evident, as is the closer relationship of the 6 series average to the MM-type reconstruction.”

    So McIntyre says he’s responsible for a type of reconstruction, not a type of “method”, or “result”.

    In any case, all of McIntyre’s “results” or “methods” or whatever you want to call them completely ignore the temperature record after 1980. The question is, why?

  69. #69 Spence_UK
    March 2, 2006

    Chris,

    McIntyre is very clear that the temperature graph he presents – like the original MBH98 – has no statistical skill. He does not claim anywhere that his graph represents historical temperature. He describes it as a “reconstruction” only to give it the same context as Mann’s graph, but he is quite clear in all cases that neither has any merit. By discussing it (as you have above) in terms of what that historical temperature “means”, you are entirely missing the point.

    Please show where McIntyre claims his “reconstructions” skillfully estimate historical temperature. Likewise, Burger and Cubasch present “reconstructions”, 64 of them to be precise, as opposed to MM’s 3, but equally claims none of them have statistical skill.

    McIntyre doesn’t ignore the post 1980 instrumental record. His point is (that you seem to be struggling with) is that the historical temperature estimation has no skill (have I made this clear enough yet?). Just like Burger and Cubasch claim the historical temperature record has no skill. If you accept this point, made by McIntyre, McKitrick, von Storch (04), Burger and Cubasch (05) you are comparing the post 1980 instrumental record to a bunch of random numbers; therefore you cannot make the claim that the 1990′s were warmer than the last 600/thousand years, because you do not know accurately what the temperature was in the last 600/thousand years. The only flaw in the logic is that you believe “one of the 3 curves must be right”, whereas McIntyre’s claim is “none of the 3 curves are right”.

  70. #70 mtb
    March 2, 2006

    Spence: You said: “As for letting misinterpretations stand – this is a pretty highly polarised debate, and to be honest I think you just have to accept that each side is only going to point out the mistakes of the other side, and rarely from their own side. Sure it does happen occasionally but it is the exception rather than the rule. I suspect the best you can hope for is that people will back down and admit their own errors when a clear enough argument is presented to them, and there are certainly no shortage of people on both sides of the debate that won’t even do that.”

    Actually, Spence that is an awfully bleak conclusion. I think that the BEST we can hope for is a whole lot better than that. In reality, it doesn’t really matter whether the protagonists on each side back down, admit errors, etc. What REALLY matters is that this highly visible discussion on an important, even vital, topic, on several blogs (each with their own cluster of views, values, attitudes, beliefs; their own cast of supporters, decryers, hangers on, lurkers etc) is airing the topic in a way that could never have happened before the development of the internet.

    It has to be a good thing for people involved in the debate, climate scientists and others, to be aware that their work will come under scrutiny (perhaps I should say intense scrutiny) in this day and age. It is a good thing if scientists thinking about publishing take special care about their work, and attend to what is expected of good science. And it is a good thing that more people are learning, very quickly I’ll bet, what good science really is. And it is a good thing that peer reviewers will take more care about their work, and a good thing that science journals will begin insisting that scientists comply with their already high standards re data archiving and the like.

    And it must be a good thing that science lecturers around the world will have their students following this “debate” to demonstrate how, in fact, science works. What exactly ad hominem attacks are. The consequences of not following sound scientific practice. etc etc.

    It can only be good if major policy decisions are based on better quality science, and a better informed public. And my best hope is that THAT is the outcome we will achieve from this debate.

    We should acknowledge the dilemma that some of the brave scientists are in, suddenly faced with the intensely bright spotlight of blog scrutiny, when none of us really understood just how powerful blogging could become – even one year ago.

    Scientists who did their work and prepared their papers for publication in an earlier, long ago, era had no idea that their work would come under such scrutiny. But now the spotlight of blog scrutiny has fallen on their work, the practical solution for those scientists is surely to review their work to see if it actually does meet the suddenly widely understood high standards. It it does meet the standards, good. Go with it. If it doesn’t, surely the smart thing to do is to say, “Hey, I was young, it was a different era, I didn’t really understand. I got it wrong. How can we work together to do a better job in future.” Not too surprising an admission in this incredibly complex world we live in, where none of us can hope to know more than the smallest sliver of that which is to be known.

    So all power to you bloggers, from every side. It is good work you are involved in, one and all.

  71. #71 Dano
    March 2, 2006

    Well, James, I’m not going to get drawn into an atomistic quibble about an old paper that has, today, at best the tiniest of utilities, if used to brief anyone at all.

    It’s a non-starter.

    And I don’t have the paper with me, but Mann et al were explicit in the paper that wrt the multiproxy calibration going back to the year 1400 they had not enough data to make useful predictions. I also recall the figger 3 shows extensive areas of grey pixels that indicate lack of robustness in those areas. Anyone with any experience reading papers at all would have read this paper and said it needs work.

    But, the constructed narrative works on the rubes who can’t understand or read the paper so they fall for the line that Mann et al were hiding something.

    It’s just not true, and your line that I’m lying is, in fact, wrong. Too bad for your little constructed narrative you want to believe because it sound so good to you. See my comment above for context on your narrative and how wrong it is.

    HTH,

    D

  72. #72 Spence_UK
    March 2, 2006

    mtb,

    I think your points are off at a slight tangent to mine. I wasn’t really addressing the utility of blogs, my comments weren’t really even specific to blogs, more to the wider climate science debates, both in and out of the scientific community.

    Bias is a very important factor, even at a peer-reviewed level. If you haven’t seen it, I’d recommend a look through some of Roger Pielke Jr’s thoughts on the subject over at Prometheus, where he has discussed the influence of bias in peer-reviewed journals.

    It is simply a fact of life that we are quick to criticise those we disagree with, and give those who we agree with a pretty loose rein. That doesn’t make an argument false, it doesn’t make blogging a waste of time, it is just a straightforward recognition of the realities of the way people apply critical thought and debate. Awareness of this practicality can only help to understand arguments. What counts isn’t the speed of the criticism, or who makes it, but the validity of the statements made.

    Out of curiousity, who do you think might use your quote – “Hey, I was young, it was a different era, I didn’t really understand. I got it wrong. How can we work together to do a better job in future.” – and why? This is the sort of thing that I believe is a rare event (not impossible, but rare) because it means people have to change strongly held beliefs.

  73. #73 James
    March 2, 2006

    Dano:

    “And I don’t have the paper with me, but Mann et al were explicit in the paper that wrt the multiproxy calibration going back to the year 1400 they had not enough data to make useful predictions. I also recall the figger 3 shows extensive areas of grey pixels that indicate lack of robustness in those areas”

    Pitiful.

  74. #74 Dano
    March 2, 2006

    What is pitiful? that I can’t recall the paper verbatim, or that you used an argument that can’t hold water?

    But enough of this.

    It is now 2006.

    In the year 2006, we have ~a dozen or so subsequent MP reconstructions, all of which have greater skill and are used in concert with dozens of utterly different indicators across scores of disciplines that say roughly the same thing.

    That is: there are, literally, piles of other empirical evidence to point to that say roughly the same thing.

    Policy-makers are given executive summaries of the piles of evidence that say roughly the same thing.

    They are not given one chart from 8 years ago. They are given executive summaries of piles of cross-disciplinary empirical findings.

    The majority of them indicate the climate is changing at a likely unprecedented rate.

    So, the point you bring up? It matters not a bit.

    No one cares about that one chart from 8 years ago, inflated by some people to make it seem as if it is the only thing decision-makers see when they are briefed.

    Get it? That constructed narrative has been passed by. Buh-bye. Long gone.

    Best,

    D

  75. #75 James
    March 2, 2006

    What’s pitiful is that you contest a point I made, then when caught out protest that it “doesn’t matter/moved on”.

    I would have thought a discussion of the skill of the multiproxy reconstructions was quite germane to a thread about, er, multiproxy reconstructions. But there you go.

  76. #76 Chris O'Neill
    March 3, 2006

    According to Spence_UK:

    “you are comparing the post 1980 instrumental record to a bunch of random numbers”.

    In that case we’d better cut off funding for all paleo-climate research since all they produce is a “bunch of random numbers”.

    If McIntyre is so good at understanding analyses of paleo-climate data, when is he going to do something useful and publish his reconstruction? Or are you saying that through sheer bad luck, virtually all of the proxies suddenly become inaccurate before 1500, all of the tree-rings, all of the dO18 in caves, in ice, in sediments, in coral and every other dO18 capture process, all of them are useless before 1500? When is McIntyre going to produce a reconstruction that shows that MBH’s actual results, which are the thing that really matters, are wrong? Several more recently produced reconstructions have been done using different methods from MBH98. McIntyre hasn’t said anything about most of these methods. Mann referred to some of these and to papers testing the validity of them in http://www.dailykos.com/story/2006/1/20/7194/94155 .

    If you really believed that someone used the wrong method to get the right results in the past well fine but how long does it take for you to realize that the only thing that matters now is that we have the right result now. When will the contrarians move on to arguing the thing that really matters, i.e. that we have the right result now?

    BTW Spence_UK also said: “but he (McIntyre) is quite clear in all cases that neither has any merit.” Yeah sure, he prints a big graph in his publications which is significant in a particular way and then buried somewhere in the text says it’s just a random number.

  77. #77 James
    March 3, 2006

    Chris,

    Actually, McIntyre has quite a lot to say about Mann’s Daily Kos interview:

    http://www.climateaudit.org/index.php?s=daily+kos

    BTW, unlike your pal Dano, you seem to think that MBH’s results are “the only thing that really matters”. I thought the paleo team had “moved on”?

  78. #78 Spence_UK
    March 3, 2006

    Chris,

    “In that case we’d better cut off funding for all paleo-climate research”

    This is called a hyperbole. You’ve taken something I said and drawn a ludicrous conclusion from it, and are trying to pin that ludicrous conclusion on me. If anything, my opinion that the existing reconstructions are unreliable suggests that perhaps we need to put more effort into paleo-climate research.

    I see we’re also trotting out the usual fallacies about “negative” research. Negative research (i.e., this doesn’t work, this paper is not correct) is just as valid and valuable in the scientific context as “positive” research. Statistical studies have underlying assumptions that aren’t always obvious. By getting a better understanding of these underlying assumptions and the statistical qualities of the data, you can pave the way for better research. That’s why Steve has been involved in peer review for various paleo climate papers in climatology, that is why he is giving presentations to the NAS panel. What he has to say is clearly important, even if he doesn’t answer your pet question.

    By the way, your statement,

    “Or are you saying that through sheer bad luck, virtually all of the proxies suddenly become inaccurate before 1500, all of the tree-rings, all of the dO18 in caves, in ice, in sediments, in coral and every other dO18 capture process, all of them are useless before 1500?”

    Is simply more hyperbole. I’m not saying that at all. I am saying the existing paleo climate constructions have a number of weaknesses both in data and methodology, and citing more than one paper (not just MM, but vS and BC) to back this view up. None of the papers say anything like what you’ve written above. But the papers do suggest that existing global temperature reconstructions are very unreliable.

    Incidentally, Burger and Cubasch found that the reconstruction they tested began to wobble as late as the end of the 19th century, and had fallen apart by 1600. So no, there isn’t some strange cutoff at 1500.

    Science doesn’t stop, Chris. People will be trying to do bigger and better paleo climate reconstructions for the next hundred years, I suspect. Perhaps more accurate, more detailed, higher bandwidth, greater length etc. That isn’t a bad thing in my view.

  79. #79 Tim Curtin
    March 3, 2006

    Chris O’Neill: “When will the contrarians move on to arguing the thing that really matters, i.e. that we have the right result now?”

    Hi Chris: Well if you are right about AGW,I have to tell you that IPCC’s forecast of up to 4C warming has already been achieved this summer but about 50 years early in Canberra, Australia, yet life goes on very comfortably (even if not so well in Perth, WA, with its coldest ever summer). My garden blooms as never before. So IPCC is right and “climate change is the greatest threat facing humanity” according to Tim Flannery, and worse than terrorism, according to Tony Blair (if I lived in Baghdad I would rather take my chance with “climate change” (summer temperatures having always been above 40C for the last 5000 years) than with Sunni/Shia terrorism. What then? I myself have this week sold my Excel coal shares and bought Toro uranium, even though the Prospectus quotes the Ausralian Labor Party’s Manifesto’s commitment that no new uranium mining will be permitted if it ever returns to power, alhough it is also committed to ratifying Kyoto in full. BTW perhaps you (and Dano and Ken Miles) could tell us what you-all have done to put your money where your big mouths are. I recognise that clowns like Tony (WMD) Blair see no choice but to go nuclear – when it comes to picking investments it’s good to go with the flow (until just before the bubble bursts, which perhaps would be when our fearless 3 see the light, I hope they let me know in time to sell Toro).
    But I wonder if we “do have the right result now”. Dendrochonology began at the University of Arizona. Some of its researchers’ recent study of tree rings at Bighorn Basin shows clearly a NEGATIVE correlation between tree rings and instrumental temperatures there since 1895. Karl Popper suggested some 50 years ago that if an hypothesis was rejected just once by empirical data, then it would have to be revised or discarded. It is the inability/refusal by Mann’s hockey team to admit that all too many of their proxies fail this test, leading them to frauds worthy of Ken Lay’s Enron, which has prevented the emergence of a scientific consensus on whatever “climate change” there may be in Huston or Canberra.

  80. #80 Tim Lambert
    March 3, 2006

    This is Tim Curtin, from the link that Ken posted:

    That emissions of carbon dioxide are responsible remains to be proved, and you of all people should know there is no econometric modelling that demonstrates this essentially implausible result, given that the increase in atmospheric CO2 of about 100 ppm over 200 years (a growth rate of 0.15 per cent p.a.) has only reduced the non-CO2 components of the atmosphere from 99.972 ppm to 99.962 ppm – small changes may have big effects, but that such a further change over the next century (0.01 per cent) could raise the average temperature in Britain by 50.00 per cent in 20-100 years (as claimed by the IPCC as well as by Bob May in Sydney recently) seems unlikely (albeit a delightful prospect to refugees from that climate like me).

    Says it all, really.

  81. #81 Tim Curtin
    March 3, 2006

    “Says it all, really.”

    Thanks Tim Lambert. When Celsius whoever he may have been picked freezing point for 0C on his scale, then if IPCC and Flannery cite temperature changes of +4C as “the greatest threat facing humanity”, 4C sounds big (since average annual temps in UK are around 10C), but if the IPCC cited all temperatures in Kelvins, then the % equivalent of an increase of 4C would not sound very alarming. So I am all in favour of citing all temperatures in Kelvins.

  82. #82 Tim Lambert
    March 3, 2006

    Nobody except you talks about % changes in Celsius because it’s completely meaningless. A change of 4 degees C is a change of 4K. Duh.

  83. #83 John Cross
    March 3, 2006

    Tim Curtin: Does the above quote that Dr. Lambert provides still represent your point of view?

    Spence_UK: I can still agree with some of what you wrote above. However I would like to clarify none thing. You stated that I am saying the existing paleo climate constructions have a number of weaknesses both in data and methodology, and citing more than one paper (not just MM, but vS and BC) to back this view up.

    Now, M&M’s argument is that the statistical results for the 15th are not valid. vS provides an interesting take on things but still shows that the current warming is larger than previous periods. While I have not read BC, I have read the review of it by others (including M&M) and I gather from it that while there are a number of possible reconstructions depending on your prior assumptions, none show previous warm periods being warmer than the current ones.

    So to summarize, according to M&M, you can’t tell if we are warmer than anyother time. The others imply that we are currently in an “unprecedented warm period”. For those who are interested in paleoclimatology reconstructions and comparing them to today’s temperature the results tend to support what has been said all along.

    However I belong more to the field that tends to not put a lot of weight on the value of comparing current temperatures to previous temperatures. If we are unsure of temperature, how certain are we of the forcings that cause temperature (I know I am asking for arguments from some members of the climate community)?

    What I find interesting about BC is that most of the reconstructions do follow MBH quite closly but when they differ significantly, they differ by being a great deal cooler than the MBH. If there were the correct ones, it could have serious implications for the climate sensitivity value implying that climate will be more sensitive than less to changes of CO2. To me this is the important lesson of BC.

    Just some random thoughts.

    Regards,
    John

  84. #84 James
    March 3, 2006

    John,

    I think you’re missing the point. Neither M&M or B&C propose alternative reconstructions. They’re pointing out (in different ways) that the reconstructions alluded to are not robust.

  85. #85 Eli Rabett
    March 3, 2006

    One has to go further than John Cross. First there is an important difference between climate variability and climate sensitivity. Variability is (at least in my view) a pseudo-random variation in climate attributable to internal causes which may have chaotic components. Sensitivity is the response of the climate system to external forcings such as land use, volcanoes, fossil fuel burning, industrial emissions, solar changes. To an extent all of the external forcings can be put on a common basis in terms of energy fluxes at the top of the atmosphere.

    vS&Z point out that the Mann reconstructions imply a very low value to climate sensitivity. M&M and various other denialists hold that the intrinsic variability is so high that one cannot claim that the current excursion is outside the natural variability. This is very different from vS&Z

  86. #86 Spence_UK
    March 3, 2006

    John,

    It is a mistake to treat the graphs generated by either McIntyre or Burger and Cubasch as temperature reconstructions. They are outputs from a statistical method, achieved by mixing and matching methods that have been declared as valid by one of the many multi-proxy studies in existance. They haven’t claimed their alternate histories are “better” than MBH, but they are checking the reliability of the results.

    The problem with having a large number of different methods that claim equal validity, is that if they give substantially different answers, then the statistical significance attached to each of those is weakened. For example, if I have 20 different methodologies that I can apply, and each produces a quite different result, the chances are one of those results will be significant at the 95% level. But that arrives by chance alone; it doesn’t mean we have discovered something of merit. Burger and Cubasch identified no less than 64 different methodologies by cross comparing different multi-proxy studies. And most of them have no merit, even when tested against just one loose measure of statistical skill.

    On the other hand, if the results turned out to be robust to changing methodology, the statistical significance would not have been weakened.

    But B&C don’t stop at identifying the lack of robustness. They look into possible causes, and say there is no one simple cause, but they suggest the extrapolation of the linear relationship between the proxy and the temperature record is most likely to be one of the major issues. They point out that proxies are calibrated over a narrow range, but then that linear assumption degrades as you move further from the calibration region. At best, it will remain linear but the error grows as you move from the centre, but at worst the linear relationship could break down completely outside the calibration interval.

    The point here, is that the areas where it may have been warmer in the past, coincide with the areas on the multiproxy studies that have the greatest error – and an error that the current group of studies substantially underestimate. This leads to the conclusion that the studies are simply too unreliable in their present form to deduce that it is warmer today than at any time in the last 1000 years.

    vS is a different analysis – he claims that the MBH method underestimates past variability, which means the graph could have gone both up and down by a much larger margin. He doesn’t put a figure on this though – it is dependent on the proxies. His reconstructions are based on model outputs and therefore not related to “true” historical temperature, but an abstract “artificial” historical temperature, so it is impossible to draw conclusions about “true” previous temperature from this paper.

    Of course everyone wants to interpret these results in their own way to determine whether or not climate change is an issue. I have my own take on this, which involves fractals, self-similarity, scale invariance and the Hausdorff dimension. But that debate is for another day :-)

  87. #87 Dano
    March 3, 2006

    James tap-danced:

    What’s pitiful is that you contest a point I made, then when caught out protest that it “doesn’t matter/moved on”.

    nooooooo, I said what you said about MBH98 ‘hiding something’ isn’t true.

    THEN I said the issue moved on.

    I would have thought a discussion of the skill of the multiproxy reconstructions was quite germane to a thread about, er, multiproxy reconstructions. But there you go.

    It is. Relaying falsified talking points not based in fact isn’t really a discussion, though. It’s astroturf.

    Thanks!

    Best,

    D

  88. #88 Dano
    March 3, 2006

    James misspoke:

    BTW, unlike your pal Dano, you seem to think that MBH’s results are “the only thing that really matters”. I thought the paleo team had “moved on”?

    I’ve said no such thing. Something is preventing you from comprehending the written word.

    Why do you need to spread falsehoods to make your claim? Oh, wait: that’s all you’ve got. Carry on.

    Oh, and what Rabett & Cross said.

    Best,

    D

  89. #89 John Cross
    March 3, 2006

    James: I agree that M&M do not and I think I was quite clear in saying so. I am not as convinced as you about the results of BC. From what I understand (and if anyone has a link to the paper I would appreciate it – the one on ClimateAudid didn’t work) they said that there were a number of prior assumptions that had to be made in order to reconstruct. They showed the range of these reconstructions and while they all vary, there are none that show a period warmer that the current time.

    Eli: Many have gone much further than me – to quote WC “if I have not seen further it’s because giants have been standing on my shoulders”.

    I agree with your comments about vS and I was indeed referring to climate sensitivity.

    Regards,
    John

  90. #90 John Cross
    March 3, 2006

    Spence: I have been cross-posting so I didn;t see your comment. I need to get the paper and see what it says. I know that McIntyre reflects your view, but I have seen others that feel different. However I suspect that we will indeed have different interpretations of it.

    My final thought for now is that if in fact the calibration relation breaks down in warm temperatures then the climate sensitivities based on paleo-reconstructions are again underestimating climate sensitivity.

    Regards,
    John

  91. #91 Spence_UK
    March 3, 2006

    John,

    I suspect the link at ClimateAudit was removed by request. Scientific papers come with a copyright, and obtaining a copy should result in the author and journal receiving an nominal (but small) fee, unless either the author or journal choose to give it out freely. I had no luck in finding a copy on the web, so I’m assuming that the authors have not made it freely available.

    You can acquire it free from the AGU (if you have a subscription) or for a small fee (if you don’t) from here:

    http://www.agu.org/pubs/crossref/2005/2005GL024155.shtml

    Alternatively, there should be an academic or technical library near you that will stock the journal, which may work out cheaper, especially if you have a lot of articles you wish to catch up on.

  92. #92 Dano
    March 3, 2006

    I let my subs lapse else I’d have quoted from the BC paper by now, so I apologize (apologise) for not lending my historic services to this debate.

    Hopefully I’ll have them back up within two weeks, but that requires me driving to Seattle and giving a signature (no fax accepted).

    And let us note that, for the most part, this ‘debate’ is not being carried out because of the flood of contradictory papers being published in the journals…

    Best,

    D

  93. #93 Tim Curtin
    March 3, 2006

    Tim Lambert:

    Yes a change of 4 in C is the same as a change of 4 in k, but why does not the IPCC use k? In my UK example, its predictions sound more alarming when stating UK’s annual average temperature will rise from 10C to 14C (40%) in 50-100 years than if one says it will rise from 287.15k to 291.15k (1.4%). Presentation is everything when advocacy reigns, as IPCC showed with its use of the hockey stick as backdrop. Or are you saying that measuring change is meaningless?

  94. #94 Dano
    March 3, 2006

    I suspect this is too narrow of a cultural reference for folks down there:

    I read the comment immediately above and think of the sound that Scooby and Shaggy made when they started to run, but instead their feet ran in place for a while before they started going forward.

    It’s dodgy, I know, but so much more amusing than trying to imitate a tap-dancing sound…

    Rooby-doo!

    Best,

    D

  95. #95 Ian Gould
    March 3, 2006

    Better yet, Tim, let’s restate the predicted change in Megakelvins that way it sounds even smaller.

    And if that doesn’t work, there’s always the GigaKelvin…

  96. #96 Tim Lambert
    March 3, 2006

    Dano, Scooby Doo was a fixture on Oz TV. I’ll give you a narrow cultural reference: I think Curtin’s line would work as a hard-hitting question delivered by Norman Gunston to the IPCC.

  97. #97 Chris O'Neill
    March 4, 2006

    James says:

    “I thought the paleo team had “moved on”?”

    You’re not getting the point here James. The paleo team have moved on to better methods and testing of methods. The results haven’t changed very much from MBH98.

  98. #98 Kenneth Blumenfeld
    March 4, 2006

    Tim Curtin,

    It is not that you *shouldn’t* use percentages when comparing temperatures in Celsius, it is that you CAN NOT. Shall we reiview the basic levels of data?

    Nominal: Values have no numeric significance nor any logical ordering; 1 for grapes, 2 for strawberries 3 for cement trucks. And so on.

    Ordinal: Values have logical ordering, but that’s all. Like a ranking system. 0 for strongly disagree, 1 for disagree, 2 for don’t know or care, 3 for agree, 4 for strongly agree. You can not add, subtract, multiply or divide these values. You can, however compare them (qualitatively, that is).

    Interval (ding ding ding!): As implied by the name, these values have a consistent “interval size,” but they have an arbitrary zero point. So the distance between 4 degrees C and 5 degrees C is the same as the distance between 856 degrees C and 857 degrees C. You can therefore add and subtract these data, but you may not, I repeat: may not, multiply, divide or compare them in “ratio” terms. Bringing us to…

    Ratio: values that have a natural, logical, zero point and consistent interval size. Like Kelvins (because zero means zero), or weight in kg, or population.

    Dano:
    I believe Rich Hall–formerly of SNL and a lesser known HBO series in the 1980s called “Not Necessarily the News”– had a “sniglet” (made-up word that should be a real word) for the revving up of one’s feet before running. I think he called it the “Flintstep.”

  99. #99 Chris O'Neill
    March 4, 2006

    Spence_UK wrote:

    “I see we’re also trotting out the usual fallacies about “negative” research. Negative research (i.e., this doesn’t work, this paper is not correct) is just as valid and valuable in the scientific context as “positive” research.”

    The point I was trying to get at is that McIntyre is not very good at understanding analyses of paleo-climate data, even if he’s only admitting to not being very good at it himself. His criticisms of MBH’s use of Principal Components Analysis are rubbish. If he really understood PCA he would know that there is no fundamental need for the data to be centered to get a valid set (albeit with origin shifted) of Principal Components. The Principal Components are just the values of the data resolved onto the eigenvectors of the data covariance matrix, with the only proviso being that the eigenvectors have to pass through the centroid of the data when the data is not centred at zero. The data-noncentredness makes no difference to the covariances, so it makes no difference to the covariance matrix eigenvectors. And contrary to what McIntyre says, there is no need to normalize (or standardize as he calls it) the data to have variance equal to one. Refer to a tutorial to see that normalization doesn’t need to be used. McIntyre also has the idea that there is no formal rule for deciding how many PCs are needed. Yes, I’m sure he’s looked for one.

    Spence_UK also wrote:

    “Incidentally, Burger and Cubasch found that the reconstruction they tested began to wobble as late as the end of the 19th century, and had fallen apart by 1600.”

    “fallen apart” meaning up to 0.5 degrees C different from MBH. As I’ve said before this 0.5 degrees C does not change the conclusion that it is now warmer than anytime since 1400. You don’t need to be very accurate to reach this conclusion. On a related point, I don’t know why so many people are obsessed with whether the medieval period is warmer than now when there is little argument that it was quite likely warmer, say, 8000 years ago. Why is it so important to some people that the medieval period in particular was warmer than it is now?

    Spence_UK wrote later:

    “B&C point out that proxies are calibrated over a narrow range, but then that linear assumption degrades as you move further from the calibration region.”

    One of the advantages (if you can call it that) of the 20th century for calibrating proxies is that the 20th century covers such a wide temperature range, from little ice age temperatures at the beginning to warm age temperatures at the end. This enables paleo-climatology to test proxies over this range against instrument temperatures. So any unknown non-linearity in proxies is not going to come into play unless the paleo-temperature is outside the calibration range. As far as I know the paleo-proxies are always below the highest temperature values occuring in the calibration period, so there’s no chance of underestimating temperature due to unknown non-linearity.

    Spence_UK also wrote:

    “Science doesn’t stop, Chris.”

    Nice to be reminded of the bleeding obvious.

  100. #100 Tim Curtin
    March 4, 2006

    Kenneth Blumenfeld: you said “It is not that you *shouldn’t* use percentages when comparing temperatures in Celsius, it is that you CAN NOT.”

    Of course, economists have known for about 200 years that you can have ordinal, non-additive, utility, but not cardinal – additive – utility. However most ordinary people – especially very ordinary people like Tony Blair – when told about this or that numerical increase in something like temperature will if told “4C up on 10C will be catastrophic” might well think, “gosh, you are right, that sounds big or even, that’s 40%, crikey, this is worse than bombs on the underground”. A few if not Blumenfeld will say that’s only 4C on 287k, perhaps not so scary. My view is (1) that the changes in the atmosphere as between CO2 and non-CO2 are inconsequential and even self-correcting (water vapour has been described as forcing as well as feedback, so more of one forcing combined with less of another may not matter much), but even if the change is to more forcing from CO2 from less from non-CO2, there is still also a concomitant decline in non-CO2 feedbacks when CO2 increases. But let’s assume that the outcome is AGW of 4C or k on 10C or 287k, what’s the problem, especially in Baghdad? I know of no definitive assessment that warming to that extent is harmful. There is no proven linear relationship or any other between polar melting and sea-level rise, and Lovelock would probably agree that there are likely to be self-correcting factors at work (eg more rain uplift from the oceans). Otherwise there is massive evidence for the beneficial impact of CO2 on agricultural and timber yields, and for the fact most people prefer warmer climates to colder. Finally, when nearly all true believers in AGW except Lovelock unite to prevent adoption of nuclear energy as the proven most cost-effective way to reduce CO2 emissions whilst maintaining living standards, can we have anything but scorn for both their science and their integrity?

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