Rutherford, Mann et al [2005]

Over at Daily Kos, Mann says that the Nomads (this is a new candidate name for the Hockey Team) have moved on and that RegEM, as in Rutherford, Mann et al [2005], is the new sheriff. At the end of the day, it’s hard to see how the RegEM method avoids any of the BàƒÆ’à‚⻲ger and Cubasch criticisms as a Daily Kos reader has pointed out (and Mann has yet to answer).

But today I’m going to visit another curiosity about Rutherford, Mann et al [2005].

There’s some very very curious relationships between Rutherford et al. and MM03. Rutherford et al. [2005] was submitted to Journal of Climate on July 23, 2003, at around the same time as MM03. As outlined below, I’ll bet dollars to doughnuts that the file "pcproxy.txt", the file at Mann’s FTP site (in Rutherford’s subdirectory) to which we were directed and now supposedly the "wrong file", was used in the original submission of Rutherford, Mann et al. [2005] and was fixed up after MM03 pointed out problems with it.

The proxy files presently at the SI for Rutherford, Mann et al. [2005] are identical to the proxy files archived with the MBH98 Corrigendum. They are undoubtedly consistent with the final version of Rutherford, Mann et al. [2005]. They are related to the MBH98 data, but the format is consistent not with MBH98, but with the later publication. Finally, as I speculated before, Rutherford, Mann et al [2005] use all the original screwy PC series.

Screwy PC Series in Rutherford, Mann et al [2005]
I’ll deal with these matters in reverse order. Early last year, based on the written description in the Rutherford prepring, I speculated that Rutherford, Mann et al [2005] used all the screwy PC series in calculations supposedly showing that the screwy PC problems did not "matter" as follows:

It may seem impossible to believe that calculations using the original flawed PC series of MBH98 are now presented as evidence that the calculation errors do not "matter", but the evidence is incontrovertible once you wade through Rutherford et al. [2005]. The data set (as used in Rutherford et al. [2005]) is not archived, so one has to rely on the descriptions in the text. The article itself states that 112 indicators were used in the AD1820 step and 22 indicators in the AD1400 step. These are exactly the same number of indicators as used in MBH98. There is no statement in Rutherford et al. [2005] that the PC series were re-calculated to correct the erroneous PC method. Thus, at this point, the evidence suggests that the Rutherford et al. [2005] dataset is identical to the MBH98 dataset. I’ll check this if and when the Rutherford et al. dataset as used is archived, but there’s not a shred of doubt in my mind on this point.

John A. is not blocked at Rutherford’s SI and archived the directory for me about 2 weeks ago and I’ve now taken a quick look at it. I’ve checked the above point and confirm that Rutherford, Mann et al [2005] did not fix their flawed PC method, but used precisely the same data as MBH98 itself – flawed PCs and all. So how this shows that the PC problems did not "matter" is a bizarre argument even by Hockey Team standards. Of course, it’s been peer reviewed by Andrew Weaver so being screwed up presumably doesn’t matter.

Nature versus Nurture
Here’s another curiosity. The MBH98 data version archived at Rutherford’s website http://fox.rwu.edu/~rutherfo/supplements/jclim2003a/data/mbh98/ is exactly the same as the data version archived at Nature in connection with the MBH98 Corrigendum. http://www.nature.com/nature/journal/v430/n6995/suppinfo/nature02478.html . This applies even to the temperature dataset anomalies-new.dat, which goes from 1854 to 1993. (Rutherford, Mann et al. say that they used the HadCRU (not HadCRU2) dataset going form 1856-1998, but archived something different. Neither MBH98 nor even the Corrigendum correctly identified the data version archived as anomalies-new.dat. There’s probably another version floating around; it’s the Hockey Team and they’ve "moved on".)

The proxy versions archived in the Corrigendum were supposed to be the versions used in MBH98. While they are related to the versions used in MBH98, they are actually the versions used in Rutherford, Mann et al. [2005]. If you look at the form of the proxy data sets archived for Rutherford, Mann et al [2005]/Corrigendum [2004], the data is collated for each step – see the files data1820.dat, data1800.dat, etc. The form and nomenclature of these files appears to be consistent with the file calls in Rutherford’s program, but do not work with the file calls in MBH98 programs archived last summer. So what was archived at Nature was not the data as used in MBH98, but the data as used in Rutherford, Mann et al [2005]. The data is obviously related but why wouldn’t they simply archive it in the form that they actually used in MBH98? I still can’t replicate their results exactly (nor can Ammann and Wahl, despite their claims to have "exactly" replicated MBH98). I doubt that much turns on this, but I can assure you that any business auditor would not be content with Hockey Team arm-waving and would insist on ironing this out. Little discrepancies are sometimes just that, but sometimes they are telltales for bigger problems. You never know what lies underneath a stone.

pcproxy.txt
Now let’s reflect a little on an old question, which keeps getting re-opened by the Hockey Team – pcproxy.txt, the "wrong file". It sure looks to me like this was associated somehow with Rutherford’s Journal of Climate article.

Originally in April 2003, Rutherford directed me to a location on Mann’s FTP site containing a file pcproxy.txt, dated in August 2002 (about 8 days after the FTP site was set up on July 31, 2002). There was also a Matlab version pcproxy.mat and Rutherford uses Matlab (Mann used Fortran). A few months later, on July 23, 2003, Rutherford submitted the first version of Rutherford, Mann et al [2003] to Journal of Climate. At around the same time, the phrase "pcproxy" occurred in a graph harvested from Rutherford’s website in 2002 by the Wayback Machine as reported here and shown again below. The figure shows that Rutherford is dealing with MXD data as well as MBH98 data – just as in Rutherford, Mann et al [2005] originally submitted in July 2003.

The form of pxproxy.txt is exactly compatible with the Matlab formats of Rutherford’s other work. So doesn’t it seem like a teensy bit likely that Rutherford actually used pcproxy.txt – warts and all?

After publication of MM03 in October 2003 (so the timing is about the same), Mann said that the data version [pcproxy] had been prepared especially in response to my alleged request for an Excel spreadsheet. We’ve discussed this sordid story before, as Mann’s story was a complete fabrication (this has not prevented Crowley from publishing the fabrication in Eos). Obviously it wasn’t prepared for us (and we noticed the problems and re-collated the entire data set), but why was it prepared and how was it actually used?

I’ll bet dollars to doughnuts that Rutherford’s original submission to Journal of Climate (dated July 23, 2003 just prior to MM03) used pcproxy.txt, collation problems and all (and that what Rutherford linked us to was the data collation that he was using for that study.) Then when MM03 pointed out the collation problems in pcproxy.txt, Rutherford and/or Mann realized his oops and deleted the pcproxy file. Mann then commenced his disinformation about us using the "wrong" data, when, in fact, it was Rutherford, Mann et al in their 2003 submission to Journal of Climate that used the "wrong file"

I’ve discussed on many occasions how MM03 has stood up – see MM03 Scorecard here. All the big criticisms have stood up – especially about the incorrect PC series, although we were then unable to explain why the MBH98 PC series were wrong (but did so in MM05- GRL). The only points that might not have applied to MBH98 (and we acknowledged this promptly were the collation errors, which we speculated might have been introduced by Rutherford at a later date.)

Here’s where Rutherford and Mann get a little cheeky. Rutherford, Mann et al. [Journal of Climate 2005] stated:

It should be noted that some falsely reported putative “errors” in the Mann et al. (1998) proxy data claimed by McIntyre and McKitrick (2003) are an artifact of (a) the use by these latter authors of an incorrect version of the Mann et al. (1998) proxy indicator dataset…

You have to watch their language carefully. This is a little more craftily worded than Mann’s original allegations to David Appell (and some of his later public statements) and does not say that all the MBH98 errors identified related to pcproxy – only "some" of them and does not claim that we used incorrectly collated data in our calculations (although they slyly spread this disinformation elsewhere).

The irony here is that I’ll bet that the so-called "incorrect version" was the version used by Rutherford, Mann et al. in their July 23, 2003 submission to Journal of Climate. After MM03, they coopered up their calculations with a re-collation of the data. I’ll bet that the files presently archived in the Nature Corrigendum did not exist prior to MM03. In fact, they should be thanking us for pointing out a problem with the data that they had used in their Journal of Climate submission, although I won’t hold my breath waiting for a thank-you note.

BTW, in an earlier post, I pointed out that Rutherford, Mann et al. completely failed to discuss any of the problems raised in our 2005 papers. I wrote to Andrew Weaver about this, asserting that this constituted a lack of full, true and plain disclosure and ended up with very unsatisfactory answers as to why Rutherford, Mann et al. should be permitted to avoid discussion of PC problems which they knew to exist. Despite this lack of full disclosure, Weaver did not intervene and allowed a very incomplete record to be published. This ended up having some further effect as Houghton, in his testimony to Congress, credited Rutherford Mann et al. [2005] with supposedly discussing our 2005 articles even though this was untrue. It is frustrating that Weaver did not require full disclosure and that the authors Rutherford, Mann, Bradley, Hughes, Jones, Briffa and Osborn failed to provide it.

The New Sheriff
Mann now says that they’ve been using RegEM for over 6 years. There’s strong, verging on conclusive evidence, that the collation problems that Mann denied as existing as to MBH98 have affected their RegEM collations. So there are 4 years of calculations before MM03 which could be affected by splicing and collation problems – all of which are additional to the PC problems and bristlecones. In this case, not only did they move on, but they deleted the files when they de-camped.

60 Comments

  1. Posted Jan 28, 2006 at 10:27 AM | Permalink

    John A. is not blocked at Rutherford’s SI and archived the directory for me about 2 weeks ago and I’ve now taken a quick look at it.

    You can’t be serious that they’ve blocked you from accessing the site, surely.

    These people do claim to be scientists – right?

    Are true scientists afraid to have their methodology checked by others?

  2. John A
    Posted Jan 28, 2006 at 10:35 AM | Permalink

    I always thought "Kyoto Zombies" would have been a good name for the Hockey Team. They would have had a weblog called "Undead Climate – for Kyoto Zombies by Kyoto Zombies"

    I also think you missed a trick by not copyrighting your corrections to Mann’s original file. But heck, such is the ethical vacuum these days that plagiarism seems such a trivial offence, especially when they’re trying to save the world.

    I edited your writing for paragraphs after I realised that my eyes were watering trying to parse the original. I left the speling mistaks in the orignal though…

  3. John A
    Posted Jan 28, 2006 at 10:36 AM | Permalink

    Re: #1

    You must be new around these parts, stranger.

  4. Posted Jan 28, 2006 at 10:37 AM | Permalink

    Just found this article:

    The IPCC states that “most of the observed warming over the
    last 50 years” is of human origin. The report says that late 20th-
    century temperatures shot up above anything the earth had ex-
    perienced in the previous 1,000 years. Michael E. Mann, a geol-
    ogist at the University of Virginia and a lead author of the IPCC’s
    past-climate chapter, calls the spike “a change that is inconsis-
    tent with natural variability.” Lindzen dismisses this analysis by
    questioning the method for determining historical temperature.
    For the first 600 years of the 1,000-year chronology, he claims,
    researchers used only tree rings to gauge temperature and only
    those from four separate locations. He calls the method used to
    turn tree-ring width into temperature hopelessly flawed.

    Mann was flabbergasted when I questioned him about
    Lindzen’s critique, which he called “nonsense” and “hogwash.”
    A close examination of the IPCC report itself shows, for in-
    stance, that trees weren’t the only source of data “¢’‚¬? ice cores
    helped to reconstruct the temperatures of the first 600 years,
    too. And trees were sampled from 34 independent sites in a
    dozen distinct regions scattered around the globe, not four.

    You seem to have studied this data heavily. Which is correct?

  5. Steve McIntyre
    Posted Jan 28, 2006 at 12:07 PM | Permalink

    In the MWP portion of Mann’s reconstruction, there are 2 ice cores (Greenland, Quelccaya); and the rest are tree ring sites. There are 6 non-North American sites: Polar Urals, Tornetrask (Sweden), France, Morocco, Argentina and Tasmania and 27 North American sites which are combined into 3 principal component series which mine for hockey stick shaped series using Mann’s incorrect PC methodology (although bristlecones dominate anyway).

    Most of the series just function as noise in Mann’s methodology and the North American PC1 imprints the reconstruction; this in turn is dominated by bristlecones. Bristlecones have a 20th century growth spurt which specialists have attributed to non-climatic CO2 fertilization.

    It is correct to call Mann’s method “hopelessly flawed”.

  6. Brooks Hurd
    Posted Jan 28, 2006 at 1:47 PM | Permalink

    I remember several salesmen who worked with me on my first job telling me “if you can’t dazzle them with brilliance, then baffle them with BS.”

    I never really agreed with this approach, however it seems to me that Mann et all do accept this method for making their points.

  7. Posted Jan 28, 2006 at 3:37 PM | Permalink

    #2 : I suggest “Surreal climate” !

  8. Pat Frank
    Posted Jan 28, 2006 at 4:41 PM | Permalink

    Reading all the Rutherford and Mannish comings and goings, and tooings and froings that Steve described in the essay above, an adage spontaneously resolved itself in my mind, “Oh what tangled webs we weave, when first we practice to deceive.”

    It looks to me, Steve, granting your analysis, that Mann et al., have traversed from possibly (just barely) honest error into willful fraud. One is then led to wonder whether David Deming’s report that a climatologist tried to recruit him into getting “rid of the Medieval Warm Period” reflected what was a conscious project right from the start.

  9. Louis Hissink
    Posted Jan 29, 2006 at 12:42 AM | Permalink

    #4

    Nicholas, alas your article describes Mann as a geologist – he isn’t – http://www.realclimate.org/index.php?p=47 he has primary qualifications in math and physics.

    Geologist he sure isn’t but Brooks and I are.

  10. Posted Jan 29, 2006 at 1:30 AM | Permalink

    It seems to me, until there is evidence of decent correlation between tree ring width or density with temperature, any analysis which relies heavily on tree rings has to be highly suspect.

    I also think that perhaps the most reliable record we have of climate history is written evidence. While it may be subjective, rather than objective, it is evidence which is of a rather fixed nature – if the record says there was a drought in Europe 1253, then chances are there was. We don’t know how many mm (or inches) of rain fell there that year, but the record should give a rough idea. Until the past climate reconstructions match the anecdotal evidence, I don’t see how we can tell whether it’s trustworthy. Therefore “getting rid of the Medieval Warm Period” seems to be a difficult task to me. The only way would be to prove it was only a local phenomenon. But if the proxies don’t show it happening, then I would argue the proxies are probably wrong.

    I’m not a scientist, I’m just someone interested in well researched, well argued information about past and present climate among other things. I’m afraid the antics of Mann and company have made it necessary to be very skeptical of any climate evidence prevented until it’s thoroughly verified, at least to my eyes.

    Thanks for the information. I’m looking forward to more analysis of the research.

  11. Steve Bloom
    Posted Jan 29, 2006 at 2:06 AM | Permalink

    We do seem to have been a little short on the MWP here in California: http://tinyurl.com/bj6f8

    But of course these are just more proxies that can’t mean anything in the face of anecdotes.

    John writes: I put Steve’s very long URL into tinyurl.com. It points to the same place.

  12. Posted Jan 29, 2006 at 2:12 AM | Permalink

    #11, you seem to have missed the point entirely.

    Anecdotal evidence is quite firm that there was a warm period during Medieval times IN EUROPE.

    A number of proxy studies have been carried out IN EUROPE back to Medieval times.

    Therefore, those proxy studies should show that warm period. Additionally, we should be able to estimate just how warm it was based upon the records from that time, and check that the reconstruction shows approximately the correct amount of warming.

    For example, I have heard that the historical record shows crops grown in Greenland during that period. If the type of crop is known, and we know roughly what temperature range that type of crop can survive and grow in, then we can guess the temperature at that location and time. If proxies which purport to be able to show what the temperature what at that location and time show something different, that throws doubt upon the accuracy of the proxy.

    It seems to me, until this kind of research has been done, the assertion that proxies are a valid way to measure past temperature is just that – an assertion.

    At the very least, it’s necessary to compare the proxies against recorded, modern-day temperatures to have even a vague idea of whether they’re an accurate measure of temperature. This means tree rings and ice cores. However, comparing the proxy results to historically known temperatures would be a better sanity check.

    As for whether the MWP was a global phenomenon – this evidence you show (I only see an abstract, hard to judge how accurate it is) seems to be at odds with other evidence I have seen from other proxies. I will look for and re-analyze those other studies. But I don’t see how it alters my point, that tree rings aren’t necessarily reliable, especially if you’re trying to refute that point by referring to plankton growth (!).

  13. Posted Jan 29, 2006 at 2:17 AM | Permalink

    OK, I’m sorry, there is a link to the full article there, I just didn’t see it because it’s at the side.

  14. Posted Jan 29, 2006 at 2:17 AM | Permalink

    … and it seems to be subscription-only so I can’t read it anyway. Oh well.

  15. Posted Jan 29, 2006 at 2:31 AM | Permalink

    I must apologise for posting so many comments and getting side-tracked.

    I have absolutely no idea of the veracity of this information, or any potential bias, as I have never heard of this site before, but this is interesting:

    CO2 Science

    According to the studies summarised there, there is evidence of a MWP in NW Alaska, the Canadian Rockies, Chesapeake Bay, the Atlantic Coast and Panama. There is also, supposedly, much evidence of drought in Central and Western USA during that period, but I’m not knowledgeable enough to say whether drought conditions are necessarily linked to high temperatures. My intuition is not to make this assumption without something to back this kind of link up. For all I know, warmer could also mean wetter, at least in some areas.

    They don’t specifically mention California, so it may well be the case that this MWP did not extend there, although it’s pretty suspicious if it was present in Alaska and Panama, but not California, geographically speaking.

    Still, I think there is quite a bit of evidence it wasn’t related only to Europe. However, as you point out, there is other evidence that some areas were spared the MWP. I’m not sure how to reconcile that, except to say that maybe it affected some of the world, but not all of it. I just don’t know.

    Regardless, as I said, in areas where we know the MWP had an effect, any proxies not showing that effect from those locations ought to be suspect and reviewed. Additionally, proxies for which the mechanism of the relationship between temperature and proxy data isn’t properly understood should be used with extreme caution – such as tree rings.

    If I were studying climate, I think I would want to work on algorithms for de-auto-correlating the data, to see if I could reconstruct signal from single proxies which could have recognisable features useful for verifying the data being examined. I wouldn’t just throw the data into a big data soup and see what I could cook up. But that’s just me.

  16. John A
    Posted Jan 29, 2006 at 2:23 PM | Permalink

    Cooling usually brings droughts and the expansion of deserts. For example the Sand Hills of Nebraska were just sand dunes during the Little Ice Age (they’re covered in grass now).

  17. GeorgeT
    Posted Jan 29, 2006 at 3:34 PM | Permalink

    #12: Nicholas, the best reference I’ve seen describing wriiten and other anecdotal records is H.H. Lamb’s “Climate History and the Modern World.” It’s filled with old photos, drawings, stories and other useful info. It also includes some evry interesting time series (such as tree line histories in Europe and the Sierra Nevada, storminess indices for the North Sea, and frequency of crop failures in the British Isles). Worth a read, and worth owning!

  18. Steve McIntyre
    Posted Jan 29, 2006 at 3:35 PM | Permalink

    Nicholas, if you go to the bristlecone category http://www.climateaudit.org/index.php?cat=15 and scroll down, you will see a picture of a dead medieval California foxtail in what is now tundra; and a diagram of lowering treelines from the MWP – they have been advancing up in the 20th century but have not reached MWP levels as the picture vividly illustrates. Higher MWP treelines are very characteristics throughout the American west.

    There were also higher treelines in Siberia – if you look at my posting on Naurzbaev. So if regional, the phenomenon appears to have included Europe, Greenland, Siberia, Alaska and California.

  19. Steve McIntyre
    Posted Jan 29, 2006 at 3:40 PM | Permalink

    #8 – Pat, I’ve seen speculation that the “get rid of the MWP” quote belonged to Overpeck, who wrote one of the first multiproxy studies.

    Remember how MBH98 said that they used series that they did not use – there’s an email inadvertently archived at Mann’s FTP site where they say it would be “better for our purposes” if they did not use one of those series. I pointed out to them that those “purposes” were not stated in their methodology section and inquired as to what they were and got many expletives but no direct answer.

  20. Posted Jan 29, 2006 at 5:34 PM | Permalink

    Re #11:

    Steve (Bloom), the full article about the Californian foraminifera has some interesting points:

    Our findings point to the possibility that anthropogenic warming has affected marine populations since the early 20th century, although only the ocean warming of the late 20th century has been confidently attributed to the accumulation of greenhouse gases

    and

    Our results indicate that the variability of foraminifera in the California Current in the 20th century is linked to variations in SST and is atypical of the preceding millennium. Given that the trend in global SSTs has been attributed to increases in greenhouse gases in the atmosphere (17–19), it follows that the best explanation for this ecosystem aberration is anthropogenic warming that has passed a threshold of natural variability.

    This – and the graphs – indicate that the change to more tropical foraminifera species already started in the first halve of the century, which is mainly connected to solar changes, and was on full strength in mid-1970’s, while the attribution of GHGs to the warming of the oceans is confined to the second halve, and mainly after 1975, but even that is questionable. References 17-19 are for Levitus ea. 2001, and Barnett ea. 2005. Levitus ea. 2005 only points to others (Hansen) to suggest that the ocean warming of the past five decades may be attributed to GHGs, but at the same time warns that natural variability may have a large influence for decadal periods (like the 1980-1990 heat content decrease of the oceans!). Barnett tries to link the ocean’s heat content to GHGs with a model, but the model results (significantly!) don’t catch any observed cycle between 10-100 years…

  21. Peter Hartley
    Posted Jan 29, 2006 at 9:42 PM | Permalink

    Re #11:

    I had a quick google or two after looking at the cited article on Planktonic Foraminifera off California and discovered some rather interesting facts.

    1. Looking at the origianl article, one discovers in Figure 1 that the plankton that have increased drammatically at the end of the 20th century are Globigenerina bulloides, Neogloboquadrina dutertrei, Globigerinoides ruber and Orbulina universa.

    2. Googling one finds a second article, Environmental control of living symbiotic and asymbiotic foraminifera of the California current by Ortiz, J. D.; Mix, A. C.; Collier, R. W.in Paleoceanography, Volume 10, Issue 6, p. 987-1010 in which it is stated “Species that benefit from symbiont photosynthesis (Orbulina universa, Neogloboquadrina dutertrei, Globigerinoides ruber, and Globigerinita glutinata) dominate the offshore fauna”.

    3. One then immediately asks “is it possible that the unusual 20th century behavior of these species is another indication of the powerful CO2 fertilizer effect that makes all plants (including plankton that benefit from photosynthesis) grow better?” This would seem to be an obvious hypothesis. Hopefully the authors of the first cited article did something to rule that out. These plankton might otherwise be the “bristlecones of the sea” so to speak.

    4. One goes back to the first article. No mention of “CO2 fertilization”, “aerial fertilization” or even, unbelievably the word “photosynthesis”.

    Now I know nothing about this field, but something sure is starting to smell a little “fishy” here. Are there any experts around who can tell us what is going on in this case?

  22. Steve McIntyre
    Posted Jan 29, 2006 at 10:00 PM | Permalink

    Peter, I posted up a comment on Glob bulloides earlier this year in connection with Moberg, including the following quote:

    Advantages of this proxy are (1) its unique association with the summer monsoon (G. bulloides has a subpolar habitat and would be absent in the tropics except for wind-driven upwelling), (2) linear correlation with the surface cooling due to upwelling, apparently unbiased by other influences,

    The offshore Oman coldwater diatoms are one of the very few proxies that drive up 20th Century results in Moberg. It sounds as though thre is a similar situation offshore California: increased presence of subpolar diatoms, which naturally is interpreted as evidence of global warming. Now it may be correlated to warming in the sense that increased monsoon activity does seem to be connected with warmer climates, but the diatoms themselves are direct indicators of colder water. Rather ironic in both cases.

  23. Steve Bloom
    Posted Jan 29, 2006 at 11:07 PM | Permalink

    Re #18: Steve, I followed the picture link to the related article, noticed it was based on incomplete research from 2003 and then checked Google Scholar to see if there was a peer-reviewed paper by now. There is: http://www.ingentaconnect.com/content/arn/hol/2005/00000015/00000004/art00001. The last sentence in the abstract: “Further, we find that the pattern of high-elevation conifer growth rates during the last half of the twentieth century are different than any time in the past 1000 years, indicating a distinct biological signature of global climate change.” Hmm, that conclusion sounds kind of familiar. Anyway, while there certainly is an MWP signature (and actually the CA foramins have one too, although it’s faint), the current warming is greater. I have to say, these two papers make me wonder how many other studies are now out there that bolster the Hockey Team’s conclusions with completely independent proxies.

    Re #20: And so, Ferdinand, thanks to you Hansen, Barnes and Levitus stand discredited. As if Hansen doesn’t have enough problems right now. :) Just so everyone who can’t see the full paper is clear on this point, the authors made no reference to a possible solar explanation for the warming earlier in the 20th century. Rather, they refer to the conclusion of Barnett et al (2001) that models show GHGs to be the likely culprit, even though such warming would not have been directly measurable at the time since its magnitude was less than background variability.

    Re #21: A few thoughts, Peter: Notice first of all that the two lists only have two species in common, so there’s no obvious difference in response based on symbiont photosynthesis or the lack thereof. Second, the paper found that other species (the cold water varieties) have tended to do worse, which means it’s hard to imagine any kind of uniform fertilization effect. Third, a paper like this is not going to recapitulate the entire field of foramin study, e.g. information about how these foramin species behave in other locations, but I suspect following the citations or just googling would turn that up.

  24. Posted Jan 30, 2006 at 12:30 AM | Permalink

    Since I can’t understand the technical words in those articles, can someone else tell me how this conclusion of “high elevation conifer growth rates… indicating a distinct biological signature of global climate change” meshes with the previously discussed unexplained growth spurt in conifers which could not be explained by temperature data?

    My understanding was the researchers looking at the pine tree rings found a growth spurt in the late 20th century which did not co-incide with higher temperatures than normal as measured, and there were thoughts that maybe it could be due to CO2 fertilisation. What’s different about this new case that makes the conclusion that the unusal growth is temperature-based in this particular case? In fact, where’s the proof that higher temperatures mean faster tree growth necessarily, at all? The data I saw suggested that unusually higher temperatures actually retard growth. Have I gone wrong somewhere?

  25. James Lane
    Posted Jan 30, 2006 at 12:43 AM | Permalink

    Re #23

    Steve, that paper seems to be reporting the anomolous growth of high altitude North American pines in the 20th century, previously noted by Graybill and Idso (1993) who explicity ruled out temperature as the cause, speculating about CO2 fertilisation.

    It would be interesting to know how the authors address Graybill and Idso (if they do) in the body of the paper.

    It’s also worth noting that these are not “independent proxies” – they’re the bristlecones!

  26. Pat Frank
    Posted Jan 30, 2006 at 1:01 AM | Permalink

    #23 — According to a 16,000-year drill-core reconstruction of sea temperatures off northern California, the California Current was about as warm as now 1000,1400, 2900, 8600, and 8900-9600 years ago, and warmer than now 2800, 3200, 10,000, 12,000, and 14,000 years ago. Those data are in A. Barron, L. Heusser, T. Herbert, and M. Lyle (2003) “High-resolution climatic evolution of coastal northern California during the past 16,000 years” Paleoceanography 18, 1020. The abstract is here: http://tinyurl.com/7l2p4. A 1000 year record is clearly not adequate to show the range of spontaneous climate variability.

    About GCMs, Roger Pielke, Sr. published (2004 Climate Research 25, 185–190) a test of “the Canadian Center for Climate Modelling and Analysis coupled model I (CGCM1) ensemble, the CGCM2, the Goddard Institute for Space Studies (GISS) model, and the Geophysical Fluid Dynamics Laboratory (GFDL) model),” and not one of them showed significant CO2-induced warming prior to about 1950.

    It’s hard to see how a warming that is below the natural noise would systematically influence foraminifera populations. That plus the lack of GCM-retrodicted warming means whatever was helping formainifera to grow in the early 20th century was not CO2-induced warming. Especially, that is, if one wants to believe that GCMs can reliably retrodict temperature.

    Finally, Figure 1 in a 1999 paper by C. I. Millar & W. B. Woolfenden “The Role of Climate Change in Interpreting Historical Variability” Ecological Applications 9, 1207–1216 shows that giant sequoia and bristlecone pine tree-ring proxies indicate higher temperatures than now in the California Sierra Nevada over the interval of about 1100-1400 CE, i.e., the MWP. They also discuss anomalously low conifer tree lines from those dates.

  27. Geoff Smith
    Posted Jan 30, 2006 at 4:22 AM | Permalink

    Re#23

    Steve B. – This site is becoming so data-rich that it’s hard to keep track of all the posting. However, you should read Steve M.’s discussion of Bunn here (CA & June 2005).

  28. Louis Hissink
    Posted Jan 30, 2006 at 4:40 AM | Permalink

    I like doing this,

    plant growth is also seriously affected by the magnitude of the electric field they are in.

    http://www.telecomlab.gr/2002/oct/rhodes/pap3rs/n%20061%20_p461%20-%20p467_.pdf

    is one paper – Googling gets heaps more.

    So plant/tree growth may not necessarily be due to temperature alone.

    Sorry :-)

  29. Steve Bloom
    Posted Jan 30, 2006 at 12:44 PM | Permalink

    Re #27: Thanks, I hadn’t spotted Steve’s post on that the first time through. Unfortunately, the paper is sub-blocked so all I have to work with is the abstract. I’ll look into this more, though.

    Re #26: Of course there are past temperature changes, climate being variable, but recall that the claims made by the IPCC for MBH were explicit in talking about recent climate. (IMHO the fact that the current warming has a greater amplitude than any in the past 1,000 years never did have much scientific meaning, but was emphasized in the Summary for Policymakers to show that current circumstances are atypical; i.e., the climate doesn’t just do this sort of thing by itself every few hundred years. The existence of the MWP, even an MWP greater in amplitude than the recent warming, has no effect on this argument.) What has always been scientifically important is the rate of change and the fact that the cause is anthropogenic. Also, I don’t think there scientific support for your idea that past broad climate trends are “spontaneous.” Natural (with causes), yes, spontaneous, no. I’ll have a look at your other references.

    The foramin paper proposes a mechanism for differential warming that would have had the effect of concentrating the temp increase in a specific ocean layer. Apparently these foramins are sensitive to rather small temp changes.

  30. Posted Jan 30, 2006 at 2:02 PM | Permalink

    In a book entitled “People of the Great Ocean” Philip Houghton – a friend of mine – speculated that the Polynesians – who arrived in NZ 800-900 years ago – voyaged in a period whan the climate was warm and not too windy (they travelled in open canoes). Two way voyaging from NZ to polynesia ceased shortly after – probably because it became colder and stormier.

    So this provides some evidence that the MWP got as far as the S Pacific.

    And did not John Daly track down a sacred lake in Japan where they had recorded ice formation/breakup for more than a thousand years?

  31. Pat Frank
    Posted Jan 30, 2006 at 5:52 PM | Permalink

    #29 — How does one claim a result has little “scientific meaning” at the same time one says it shows atypical behavior and is centrally featured in a report that is touted as the most thoroughly peer-reviewed climate science available? That seems rather like an effort to both have your cake and eat it as well.

    The AGW claim rests on only two legs. One is theoretical justification in terms of GCMs. The second is the purported smoking gun of MBH98. The GCMs, by virtually every measure, are inadequate. The second has been thoroughly deflated by MM03 and following. There’s literally nothing left to the AGW claim except the insistence of the purveyors. The rest, including the foram study by Field, et al., amount to little more than tendentious rationalizations.

    About climate in general, no one knows what it does every few hundred years and so your dismissal of climate variability has no scientific meaning. Dansgaard-Oeschger events, of which there have been about 18 over the last 60,000 years, however, show 5-10 degree C warming over a few decades. That makes those warming events about 10-20 times faster than the 20th century rate. No one knows why D-O events happen, but happen they do. Climate is at least semi-chaotic, meaning that swings can occur spontaneously due to the near-random oscillations of underlying processes. Almost no one disputes that.

    What’s also true is that the Holocene climate has been abnormally stable compared to past climates. We’ve been spoiled in that sense. Climate could easily return to a more variable regime without that shift having anything whatever to do with fossil-fuel CO2.

  32. Steve Bloom
    Posted Jan 30, 2006 at 11:04 PM | Permalink

    Re #31: “The AGW claim rests on only two legs. One is theoretical justification in terms of GCMs. The second is the purported smoking gun of MBH98.” Wrong, wrong, wrong. My goodness, Pat, you need to be more careful about assertions like that. Try, for starters, increasing temps on the surface, in the troposphere and (most important) in the oceans clearly linked to steadily rising GHGs with no other cause credibly proposed. Perhaps you forget that your argument on this point would be not only with me and thousands of climate scientists, but also the proprietor of this site.

  33. ET SidViscous
    Posted Jan 30, 2006 at 11:51 PM | Permalink

    Well maybe except for the troposphere bit (warming less than surface temperatures, which goes against AGW theory, hence the UHI effect discusions) and the whole “clearly linked” bit. Because Pat’s whole point was that it’s the GCMs and MBH that are purportedly doing the “clearly linking”

    But you have to throw that in don’t you, otherwise your points don’t stand at all do they.

    But it was nice of you to point the exact bits that are in contention, well not to you of course.

    I’ve always wondered. If GHGs are warming the atmosphere, and this in turn warms the ocean (Please don’t tell me it’s CO2 in the water warming the oceans). Then how does this whole AGW is causing more and/or worse hurricanes work then.

    Since Hurricanes are natures way of getting excess heat from the ocean into the atmosphere. If the atmosphere is the one doing the warming that wouldn’t quite work would it. Because Hurricanes are predicated on the atmosphere being cooler than the ocean, not vice versa.

  34. Pat Frank
    Posted Jan 31, 2006 at 1:01 AM | Permalink

    #32 — Steve you’re making the classical error of supposing that science explains through inductive extrapolations. It doesn’t, ever. Any scientific link between recent global temperatures and CO2 can be made purely and only at the GCM level. Outside of an explanation by theory, there is no explanation in science. If you insist on connecting CO2 and global temperature despite the inadequate theory, you traverse from an error of science to an error of logic, namely “post hoc, ergo propter hoc,” — ‘it came before this and therefore caused this.’

    The “no other cause credibly proposed” is meaningless in the absence of a full theory of climate change. How can all causes be credibly assessed when those known are known inadequately, and others not known are, well, not known.

    What makes your comment so telling is that you make it despite that the GCMs are inadequate. This is perhaps unlike those who actually know the GCMs to be inadequate and tout AGW anyway. In view of that last, I can only conclude that they, like you apparently, don’t understand the grounds upon which valid claims may be made within science.

    Within science, data have explanatory meaning in the context of theory, and nowhere else. My arguement about what is and is not science rests on what one finds in science journals — theory and result — the opinions of your thousands of scientists notwithstanding. The GCMs are inadequate to provide falsifiable meaning to rising global temperatures. AGW is little more than luridly politicized inductively-based conclusion-mongering. If environmental radicals, Congresspeople among them, hadn’t picked up that ball and run with it, James Hanson’s 1988 testimony before Congress would have, and properly, pretty much begun and ended there.

    And as for rising global temperatures, we’d all be more confident about that if Phil Jones would release the details of his temperature reconstructions. The stonewalling by Jones and Mann is wonderful politics, and shameful science.

  35. Posted Jan 31, 2006 at 1:13 AM | Permalink

    Re: #33

    Nobody in their right mind is proposing that warming causes more hurricaes. Even those scientists who believe that the warming is anthropogenic typically don’t claim such nonsense. Of course, there are a number of idiots who are making these claims. But they have nothing to back it up at all. One of the saddest, most funny, most aggrivating things I have ever seen was a graph of hurricane damage, in dollars, over time – being represented as “proof” that hurricanes are getting worse.

    I feel sorry for those who have an open mind and truly believe the evidence points to very significant anthropogenic warming, since with people like the ones I mentioned above on your side, who needs enemies? Every piece of garbage like that only makes their whole argument look more silly. Which is a pity because I think one CAN make a cogent argument that there is significant anthropogenic warming based on current evidence. Unfortunately, most such arguments are very poorly made and full of holes. I think this represents big gaps in our knowledge. But unfortunately it seems that there are those who believe that they must deny that such gaps exist in order to push their agenda.

    I have total respect for those who believe the evidence is clear, AS LONG AS (1) they can point to the evidence and it can stand up to scrutiny (2) they have explanations for ambiguous/contractictory evidence, and don’t just dismiss it as irrelevant, and (3) they start with the data and form their conclusions, rather than starting with conclusions and forming the data. At the moment, I personally think the balance of evidence is that we simply don’t have enough evidence for either a positive or negative assertion on the topic, but that the one thing we do know is that the climate seems to vary significantly despite us. My mind will remain open. But people making claims, which are prima facae false, and not only that but ridiculous, do the entire scientific community a disservice. As do those who refuse to submit to scrutiny and refuse to accept criticism.

  36. David H
    Posted Jan 31, 2006 at 2:22 AM | Permalink

    Re: 35 “Nobody in their right mind is proposing that warming cause more hurricanes.”

    They surely are! Yesterday here in the UK every TV and radio news bulletin and every newspaper ran an AGW scare story as they do every few days. The carbon trust regularly runs a TV ad that says so. The fact that we now have these very expensive (paid for by UK tax payers) ads and propaganda makes more people sceptical.

    Even if the science doesn’t give one doubt, the fact that we are constantly told that there are to be no significant benefits from global warming ought to make one question the theory a bit more. “It’s an ill wind that blaws naebody guid.”

    On the hand you may be right about their minds!

  37. Posted Jan 31, 2006 at 4:13 AM | Permalink

    I doubt I have to point this out to anyone, but see here and here and here and here.

    The notion that global warming is making the most destructive storms worse or more frequent is one of the most compelling appeals for greenhouse emission reductions. It has absolutely no basis in fact.

    Yes, as you noticed, I said “nobody in their right minds”, not “nobody”. As Mr. SidViscous points out, some people, who might possibly know what they are talking about, even believe a warmer planet would lead to less, and less severe hurricanes. If I wanted to be an alarmist in the most convincing way possible, I would choose to raise alarm over data that is at least ambiguous, as opposed to totally unsupportive of that position — but that’s just me.

    Even our friends over at RealClimate deal with the issue more delicately than usual, although somehow they still manage to predict our impending doom.

    Sorry for being off topic again :(

  38. Mark
    Posted Jan 31, 2006 at 9:40 AM | Permalink

    re: 34 ” “post hoc, ergo propter hoc,” “¢’‚¬? “it came before this and therefore caused this.’ ”

    actually, there’s strong evidence that warming occured FIRST, then came a rise in CO2. i’ve seen many reconstructions (sans bristlecones) indicating CO2 concentrations lag temperature changes. this is part of the solar forcing argument. we have warmed significantly since the LIA, which ended long before the GHG increases were noticed.

    for my take, as long as GCMs are incapable of predicting changes we already know about (MWP, LIA, etc.), exactly how are we to guarantee their predictions for the future are suddenly accurate?

    mark

  39. fFreddy
    Posted Jan 31, 2006 at 2:20 PM | Permalink

    Re #36 David H

    Yesterday here in the UK every TV and radio news bulletin and every newspaper ran an AGW scare story as they do every few days.

    And when that poor whale get lost up the Thames, Jon Snow of Channel 4 news managed to blame it on global warming.

    And regarding where our taxes are going, have you seen this one ?
    These boondoggles are taking on a life of their own …

  40. ET SidViscous
    Posted Jan 31, 2006 at 2:37 PM | Permalink

    And to think, it was Maggie that started it all as a Union Busting scheme.

  41. John A
    Posted Jan 31, 2006 at 3:52 PM | Permalink

    Re #38

    Following a link from that state-sponsored propaganda, I get to where I find this:

    1970s: Series of studies by the US Department of Energy increases concerns about future global warming.

    1979: First World Climate Conference adopts climate change as major issue and calls on governments “to foresee and prevent potential man-made changes in climate”.

    1. Anyone know of any studies by the US Dept of Energy about concerns for future global warming in the 1970s?

    2.What and where was this “First World Climate Conference”?

  42. Hans Erren
    Posted Jan 31, 2006 at 4:48 PM | Permalink

    re 40:
    re 2 john do you use google? First hit from “climate conference 1979″:

    http://www.wmconnolley.org.uk/sci/iceage/wcc-1979.html

    WMO proceedings of the World Climate Conference: a conference of experts on climate and mankind. Geneva, 12-32 February 1979. WMO – No. 537. ISBN 92-63-10537-5.

    It’s part of Williams orwellian rewriting of history of the predicted ice age in the ’70s. The problem is that the big advocate on this topic was Bryson a few years earlier.
    See this photocopy from Newsweek April 28 1975: http://www.numberwatch.co.uk/cooling1.pdf

  43. David H
    Posted Jan 31, 2006 at 5:15 PM | Permalink

    Re #37

    To be convincing the models need to explain all the temperature variations including ice ages and, as I said in comment 7 on p508 (Holloway), the shift in annual max and min temperature from the solstices. The latter has been reported as evidence of negative feedback.

  44. John A
    Posted Jan 31, 2006 at 5:42 PM | Permalink

    Yes, Hans, the WMO Conference of 1979. ;-)

  45. Louis Hissink
    Posted Feb 1, 2006 at 12:28 AM | Permalink

    Re #43

    No one knows what causes the ice ages, (the LIA seemed the result of the earth passing through a meteor swarm in space, Google Choson annals), so the models will never ever be able to predict climate.

    Ever.

  46. John A
    Posted Feb 1, 2006 at 5:24 AM | Permalink

    Louis ,

    I would suggest you google “Maunder Minimum” first

    Did anyone notice who wrote the timeline that climatechallenge.gov.uk uses as its primary source?

    Note: This document was created by Green House Network with editing by Ross Gelbspan and by cross-referencing a timeline posted on http://www.newscientist.com.

    Small world, isn’t it?

  47. Mark
    Posted Feb 1, 2006 at 10:09 AM | Permalink

    i think the full-blown ice ages are also tied to the earth’s “wobble” on its axis.

    mark

  48. Steve Sadlov
    Posted Feb 1, 2006 at 3:35 PM | Permalink

    It would seem that bringing in experts in noise analysis from the electomagnetism study community may be a productive thing to do.

    I tend to believe, as mentioned in the thread above, that there are notable negative feedback characteristics in the climate system. Also, the quasi chaotic / quasi quantum variation behaviors that we are becoming increasingly cognizant of in the paleo climate record are not unlike those of extremely complex, low power electrical networks or, by way of a similar analogy, radio frequency communication networks, in their expression.

    Another thought I’ve had is to use Six Sigma methodology, especially measurement systems analysis, to get a better handle on just what are the characteristic innate variations in the system. Intuitively, I tend to suspect that so called AGW is well within expected innate variabilty of the system. In other words, what are the “warning limits” and “spec limits” of key system paramters? And if we are currently withing both the warning and spec limits of the process / system, then clearly, the whole debate is much to do about nothing.

    Thoughts? Comments?

  49. Martin Ringo
    Posted Feb 1, 2006 at 4:31 PM | Permalink

    Let me ask, what I hope is, a fundamental question about the Rutherford, Mann et al use of RegEM (or any missing observation algorithm predicated on a likelihood function over the whole data set). Let Y be the data set for the estimation; let X be the data set (on the same variables but over a different period) for the verification. The — or at least one of the — problems with X is that there are missing observations precluding the application of a verification statistic in the period covered by X. Divide X in to X1 observed and X2 missing.

    Suppose we fill in the missing observations in X with an algorithm based on the likelihood function of Y, X1 and X2 (which is what the Expectation Maximization does). Now we can run the verification tests, at least they will compute. However, what have we done? We have tested on data that was manufactured from a likelihood function dependent on Y. Thus, we are testing an estimate from Y with data that is partially composed of observation estimates from the likelihood function with Y in it. I don’t know if Sir Ronald Fisher is rolling over in his grave, but the procedure strikes me as fraught with problems particularly in determining the critical region of rejection (not verified beyond the probability associated with random variation). I do not know what this says about the relative performance of two estimating procedures, say reconstruction I versus II. But I do think it is a dubious practice to test estimates against other estimates based, in whole or part, on the same underlying data.

    Are these concerns valid or am I missing something on how Rutherford et al used the RegEM procedure (e.g. the RegEM was only applied to the X1 and X2 data, as opposed to the Y, X1 and X2 data)? Note, with regard to the parenthetical exception, it would appear that the first thing to do, have creating the filled-in data set X, would be to test the hypothesis that those series in X with missing values came from the same time-series distribution as the similar series in Y. If the null hypothesis (same distribution) is not rejected, then proceed with the verifcation test. If the null is rejected, then there is an obvious question of the meaning of the verification statistics.

  50. Steve McIntyre
    Posted Feb 1, 2006 at 10:18 PM | Permalink

    Martin, I think that your concerns are all valid. One of the problems with all of these guys, including Schneider, is that none of them seem to worry about statistical issues. The only sense that I can make of it is that they are lapsed applied math guys and lapsed physicists, whose mentalities are different than people coming from economics and stats backgrounds, who have are more aware of the problems of spurious relationships. All these guys seem very quick to assume that "proxies" are temperature plus noise, without considering the possibility of totally spurious relationships. They "reify" things way too fast, it seems to me.

    I’ve done a very pretty reduction of the MBH98 algorithm to linear algebra (I’ve embedded this in my emulation of their algorithm and replicate all the verbal diarrhea and hundreds of lines of Fortran code in only a few lines of R.) It’s one of 10 things that I keep meaning to finalize.

    At the end of the day, my guess is that the RegEM algorithm is going to simply be something like MBH98 which (in its 15th century portion) boils down to a multiple regression between one spurious series (bristlecones) and 21 white noise series (the other proxies). Look at my post on Huybers #2 where I outlined this. I thought that this was rather a clever post but it didn’t attract much interst. I ought to write it up as it’s quite interesting.

  51. John S
    Posted Feb 1, 2006 at 11:21 PM | Permalink

    A fundamental distinction is between interpolation and extrapolation.

    Nothing anyone does can change that fact that to create a temperature series prior to 1850ish you need to engage in extrapolation. RegEM is one way to do interpolation – that doesn’t necessarily mean that it is ideal for extrapolation. As economists are wont to say, “there is no such thing as a free lunch”. If you are extrapolating then you have to face all the sorts of problems that everyone else faces when extrapolating.

    But hey, economists pretty much ditched PCA before it even got started in the profession. What would they know?

  52. Steve McIntyre
    Posted Feb 1, 2006 at 11:39 PM | Permalink

    speaking of PCA, that reminds me of an old post http://www.climateaudit.org/?p=107. Looking at how I did this post, I’d have a much longer teaser if I re-did it today.

  53. John S
    Posted Feb 2, 2006 at 12:02 AM | Permalink

    My first pass at the difference between MBH98/99 and Rutherford et al is that it’s the difference between maximum likelihood estimation and least squares. There are a lot of layers to go through so I can’t be sure at the moment. Is that really it?

  54. Steve McIntyre
    Posted Feb 2, 2006 at 12:12 AM | Permalink

    I’ll post up some notes on the regression module in MBH, which is a little different than anyone thinks.

    In MBH98, they do a principal components analysis on 1082 temperature gridcell series. This is a different step than the tree ring step. Then they regress 1-11 temperature PCs (depending on the step) against the proxies, including tree ring PCs. In RegEM, they have a ridge regression step and they compare the selection of the ridge parameter to selecting the number of temperature PCs to retain. But at the end of the day, you still only have 22 proxies in the 15th century network – I haven’t parsed through the code yet to see what happens. It’s good that they’ve archived code, but I haven’t had time yet to work through the steps and see how the individual functions work.

  55. Terry
    Posted Feb 2, 2006 at 12:50 AM | Permalink

    Steve:

    You wrote:

    I’ve done a very pretty reduction of the MBH98 algorithm to linear algebra (I’ve embedded this in my emulation of their algorithm and replicate all the verbal diarrhea and hundreds of lines of Fortran code in only a few lines of R.) It’s one of 10 things that I keep meaning to finalize.

    I would encourage you to finalize this, it sounds very interesting.

    It seems like it would be worthwhile (publishable?) in its own right independent of the whole “is MBH98 correct” debate. If it could be shown to have approximately the same “power” as MBH98 it would be (in a perfect world) heralded by the hockey team as a valuable addition to the immensely useful tools they claim to have developed.

    It’s simplicity suggests it could have wider applications than the MBH98 algorithms. Perhaps it would make it possible to predict what current proxy observations should be given current temperatures (relevant to your “bring the proxies up to date” point). Perhaps all the statistical tools and knowledge about linear regression could then be applied to it and some interesting implications about confidence intervals and robustness addressed (just speculating).

  56. Jeff Norman
    Posted Feb 2, 2006 at 1:06 AM | Permalink

    Re #30,

    Bryan Leyland,

    I too have have considered the Mauri arrival in New Zealand to be strangely coincidental with a MWP. I like the calmer ocean hypothesis.

    Other coincidences include but are not limited to:

    1. The Tule culture which spread eastward from Northern Alaska, across the Arctic Archipelago about 1,000 years ago and then later disappeared.

    2. The Cahokia culture which constructed incredible mound cities in the area of St. Louis about 1,000 years ago and then later disappeared.

    3. The Great Zimbabwe culture which build city complexes in Africa about 1,000 years ago and then later disappeared.
    4. The Mongol culture which invaded most of the Eurasian landmass about 800 years ago and stayed or left. In today’s Mongolia they experience winter weather conditions called (variously) “Zud”, a killing cold resulting in the deaths of Mongolians and their livestock. It seems to me that there would have to be several generations of non-Zud like conditions to allow for a horde mounted on sturdy steppe ponies.

    As I said these are only coincidences and probably do not count as objective data points like Planktonic Foraminifera say, but then Planktonic Foraminifera are natural and human history just isn’t. Right?

    That covers most of the Earth with the exception of South America and Europe. Of course we all now know that Europe did not experience a global MWP, just a regional one. ;-)

  57. Buddenbrook
    Posted Nov 29, 2008 at 10:23 PM | Permalink

    Mann and Gavin in their latest 28th Nov 2008 write:

    itself now discredited, “the hockey stick is discredited” claim”

    (a clear dig at CA) and to substantiate the claim that the criticism of the hockey stick would have “now” been discredited, they give links, via a wikipedia site, to articles that are from 2-4 years ago. As a highlight a posting on rc by Mann from December 2004 that refers to Rutherford [this study here] to prove McIntyre and McKitrick wrong. Is this really the best they can come up with 3-4 years later? Why are there no better counter arguments available on realclimate than the repetition of these age old assertions?

    Counter-arguments of which they never commented on?

    So to enquire: Where can you follow the *real* debate? With points and counter points and the requirement to substantiate your claims and admit errors? Does it exist? There must be thousands of climate scientists, surely some of them are engaging in productive discussions and debates?
    Who do I go to from the (C)AGW side to read substantiated, analytical counter arguments to what is posted here on CA, to better understand the nature of this confrontation/disagreement over the credibility of paleoclimatic records and graphs?

    And how alone is the Hockey Stick in it’s field of study? Is there a library of paleoclimatic graphs somewhere on the net that you can browse for a comparison?

    It’s pretty depressing to go to the “other side”, and try to listen to their arguments, and end up here, Rutherford 2005.

    • Dave Dardinger
      Posted Nov 30, 2008 at 8:21 AM | Permalink

      Re: Buddenbrook (#58),

      Who do I go to from the (C)AGW side to read substantiated, analytical counter arguments to what is posted here on CA

      When you find this “Holy Grail” site, please come back and tell us where it is. I’ve been searching for it for over 10 years now.

  58. Posted Nov 30, 2008 at 2:02 AM | Permalink

    Just sent this comment to RC but I’m doubtful this will ever see the light of day there:

    ===========================================

    We will, of course, be fascinated to find out in what peer-reviewed literature we will find the disconfirmation that “the Hockey Stick is discredited” – perhaps it will be the Ammann and Wahl so-called “Jesus Paper” (on the grounds that it has miraculously risen from the dead) where the brave authors invent their own statistical tests in order to acquit the Hockey Stick. These statistical tests have been heard of before in the standard statistical literature and, I’m willing to bet, never will be heard of again.

    Will it be from Professor Edward Wegman? Nope. Here is a statistician of first rank and impeccable credentials who did the heavy lifting of dissecting the Hockey Stick. His verdict?

    “Where we have commonality, I believe our report and the [NAS] panel essentially agree. We believe that our discussion together with the discussion from the NRC report should take the ‘centering’ issue off the table. [Mann's] decentred methodology is simply incorrect mathematics …. I am baffled by the claim that the incorrect method doesn’t matter because the answer is correct anyway.
    Method Wrong + Answer Correct = Bad Science.

    The papers of Mann et al. in themselves are written in a confusing manner, making it difficult for the reader to discern the actual methodology and what uncertainty is actually associated with these reconstructions.

    It is not clear that Dr. Mann and his associates even realized that their methodology was faulty at the time of writing the [Mann] paper.

    We found MBH98 and MBH99 to be somewhat obscure and incomplete and the criticisms of MM03/05a/05b to be valid and compelling.”

    But then what does he know? All Mann could do is what he always does with scientific criticism of his works – impugn the motives of the critics.

    What of the NRC Report and Gerry North perhaps? Always willing to help out friends?

    CHAIRMAN BARTON. … Dr. North, do you dispute the conclusions or the methodology of Dr. Wegman’s report?
    DR. NORTH. No, we don’t. We don’t disagree with their criticism. In fact, pretty much the same thing is said in our report.

    What about Peter Bloomfield?

    Our committee reviewed the methodology used by Dr. Mann and his coworkers and we felt that some of the choices they made were inappropriate. We had much the same misgivings about his work that was documented at much greater length by Dr. Wegman.

    What about statistical authorities on PCA and Mann’s use of it? “Bulldog” Tamino thought Ian Joliffe would approve of Mann’s exciting method, an effort which spectacularly rebounded when Joliffe demanded a retraction and an apology and ended with this:

    I am by no means a climate change denier. My strong impressive is that the evidence rests on much much more than the hockey stick. It therefore seems crazy that the MBH hockey stick has been given such prominence and that a group of influential climate scientists have doggedly defended a piece of dubious statistics. Misrepresenting the views of an independent scientist does little for their case either. It gives ammunition to those who wish to discredit climate change research more generally. It is possible that there are good reasons for decentred PCA to be the technique of choice for some types of analyses and that it has some virtues that I have so far failed to grasp, but I remain sceptical.

    So apart from Mann’s dogged insistence on never mentioning the words “McIntyre” or “McKitrick” and never, ever dealing with the substance of the criticisms made of his use of statistics by extremely well qualified scientists, we are no nearer to any explanation as to how the criticisms of the “Hockey Stick” have been discredited, except by repeating that they have been discredited over and over.

    Someone here is in denial, and I don’t think its the climate realists. When will Mann deal with substance and not spin?

    =====================================================================

  59. Posted Feb 24, 2010 at 8:14 AM | Permalink

    Hi,
    @Dave Dardinger and Buddenbrook – did you find this ‘Holy Grail’ site or do you know one that is really relevant? Would be very useful for my thesis on New Zealand and the Mauri.
    Cheers

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  1. [...] Here is the technical documentation of software SPLINA and SPLINB. The additive regression model appears to be a practical option for analysing spatially varying effects of several predictors on observed phenomena. It is attractive from the point of view of overcoming curse of dimension problems associated with the analysis of noisy multivariate data. Moreover its implementation is a straightforward extension of standard thin plate spline methodology. Splines are a standard technique well defined by statisticians and suitable for reconstruction of past climates from proxy records. Yet climate scientists associated with Michael Mann continue to develop ad hoc methodologies with questionable assumptions without the benefit of statisticians as criticised in the Wegman report. The lesson for successful prediction is like the old saw: brain surgery is not for do it yourselfers.Share and Enjoy:These icons link to social bookmarking sites where readers can share and discover new web pages. [...]

  2. [...] not entirely self-contained and so I re-visited some of our previous comments on Rutherford et al here here here here . I’m going to reprise two issues today: Collation Errors, a small but amusing [...]

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