Joe Barton's Committee has released a report they commissioned on the hockey stick by Wegman, Scott and Said (WSS). The focus of the report is much narrower than the NRC report and the results are basically a subset of the NRC report. In particular, both reports find that "off-centre" method used in Mann Bradley and Hughes' 1998 paper (MBH98) tended to produce hockey stick shapes in the first principal component (PC1). Unfortunately, WSS stop there and do not address the question of what difference this makes to the reconstruction (which is not the same as PC1). The NRC panel did address this question and found that it made little difference.
It would be cynical of me to suggest that the terms of reference for WSS were crafted so that WSS would only check this aspect of MBH98 and not whether it made a difference to the reconstruction. Not surprisingly, the usual suspects are using WSS to claim that the hockey stick is shattered into a bazillion pieces. For instance, the Wall Street Journal editorial page:
[WSS's] conclusion is that Mr. Mann's papers are plagued by basic statistical errors that call his conclusions into doubt. Further, Professor Wegman's report upholds the finding of Messrs. McIntyre and McKitrick that Mr. Mann's methodology is biased toward producing "hockey stick" shaped graphs.
Needless to say the NRC panel's findings are never mentioned in the WSJ editorial. (Nor in the WSS report for that matter.)
Wegman, Scott and Said are statisticians, not climatologists and this has lead to some errors in their interpretation of the literature. For example, the temperature graph in the first IPCC report is schematic and not quantitative, but they interpret it as if it was quantitative.
WSS do have a section that is not a subset of the NRC report -- Chapter 5, which claims to present a Social Network Analysis of authorships in temperature reconstructions. They have some pretty graphs but there is no quantitative analysis. It's possible that the temperature reconstruction community is so small that it causes difficulties with peer review but WSS don't have any numbers to support this. I think such an analysis would require you to come up with a quantitative measure and compare with other authorship networks.
All in all there seems little reason to refer to this report rather that the NRC one.
But the most serious flaw in WSS is this claim:
This committee does not believe that web logs are an appropriate forum for the scientific debate on this issue.
I mean, really.
Update: Comments from William Connolley and Michael Mann.
Part
7. Our committee believes that the assessments
that the decade of the 1990s was the hottest decade in a millennium and that
1998 was the hottest year in a millennium cannot be supported by the MBH98/99
analysis. As mentioned earlier in our background section, tree ring proxies
are typically calibrated to remove low frequency variations. The cycle of
Medieval Warm Period and Little Ice Age that was widely recognized in 1990 has
disappeared from the MBH98/99 analyses, thus making possible the hottest
decade/hottest year claim. However, the methodology of MBH98/99 suppresses this
low frequency information. The paucity of data in the more remote past makes
the hottest-in-a-millennium claims essentially unverifiable.
Part
8.
Although we have not addressed the Bristlecone Pines issue extensively in this
report except as one element of the proxy data, there is one point worth
mentioning. Graybill
and Idso (1993) specifically sought to show that
Bristlecone Pines were CO2 fertilized. Bondi et al.
(1999) suggest [Bristlecones] "are not a reliable
temperature proxy for the last 150 years as it shows an increasing trend in
about 1850 that has been attributed to atmospheric CO2 fertilization." It is
not surprising therefore that this important proxy in MBH98/99 yields a
temperature curve that is highly correlated with atmospheric CO2. We also
note that IPCC 1996 stated that "the possible confounding effects of carbon
dioxide fertilization need to be taken into account when calibrating tree ring
data against climate variations." In addition, as use of fossil fuels has
risen, so does the release of oxides of nitrogen into the atmosphere, some of
which are deposited as nitrates, that are fertilizer
for biota. Thus tree ring growth would be correlated with the deposition of
nitrates, which, in turn, would be correlated with carbon dioxide release.
There are clearly confounding factors for using tree rings as temperature
signals.
I've only had a quick look at the network analysis, but statements like this don't give much confidence in the authors "The block (cluster) structure is very clear. Michael Mann is a co-author with every one of the other 42."
Umm, yes. The data set consists of Mann and his co-authors. Much of the analysis of this graph seems to consist of repetition of the fact that (drum roll) Mann has written joint papers with every one of his co-authors.
The more relevant analysis is that of the top 75 researchers in the field, and here there's nothing to suggest that network links are any tighter than in any closely-defined field.
A big thing is made about cliques, but all you need to form a clique is one multi-authored paper.
How many ways can we wank stroke our totem?
This is all they got, folks. Same as it ever was: non-climatologists focusing on the totem, ignoring the other evidence.
Best,
D
"The most serious flaw in WSS is this claim:
>This committee does that web logs are an appropriate forum for the scientific debate on this issue."
Er, "does that" missing word somewhere?
Here is question. On page 47 under Figure 5.9 they say:
Both Esper et al. (2002) and Moberg et al. (2005)
indicate that current global temperatures are not
warmer that the medieval warm period.
I just gave a quick glance over their papers to refresh my memory and neither one says that. Also, the plots in Figure 5.9 are strange - I believe that they only show the reconstructions from the data and ignore the instrumental records used to calibrate.
I think the intended word is "doubts", as in
"This committee doubts that web logs are an appropriate forum for the scientific debate on this issue."
Just my guess.
But why don't they address the utter inappropriateness of thrashing out scientific issues in WSJ editorials?
*[Oops. My typo, not theirs. I fixed it. Tim]*
Dano
All I can hear is an echo.
You're preaching to an empty room.
The usual crowd have made their excuses and left.
Tim -
I appreciate all the insights of you and some commenters about items that WSS either missed or just weren't asked to consider. But I don't understand your reluctance to embrace the social network analysis section. That a congressman wants to analyze relationships jumped right off the page at me. Wouldn't we be well served by such an analysis of Representative Barton' network?
It would be time consuming to track all those phone calls, lunches, checks, earmarks, and votes, I admit. But wouldn't that be at least as useful to the general public as which proxies are used by which paleoclimatologists in which papers?
It's a Friday night/early Saturday, Mark, which typically means a bit of a slowdown in blog activity for everyone but the hard-drinking sociopaths over at CA. BTW, have you noticed yet how very little traction the Barton/Wegman report has gotten in the media?
I'm not sure that I see this in the report. Can you point me to a page, or a specific quote where this misinterpretation occurs?
Tim, I'm gonna nitpick a little here.
"The focus of the report is much narrower than the NRC report and the results are basically a subset of the NRC report"
I was under the impression that the NRC report stemmed from questions asked from the Barton committee, but which weren't quite? answered by the NRC report. (can't vouch for that, haven't read it yet, if anyone's read it, please chime in)
Hi all
Having a goo troll here this evening. Steve Bloom says 'BTW, have you noticed yet how very little traction the Barton/Wegman report has gotten in the media?' So what, does not mean it is not important, in general media only print AGW stories as they are biased.
A great day for honesty and truth.
Regards
Peter Bickle
Mark, the critique of the networking analysis doesn't seem to be that it was done, but rather that it was done badly.
According to David W.Scoots' homepage, he is in the Exxon network. He has received funding from Exxon in the past.
http://www.stat.rice.edu/~scottdw/
It is possible, that the funding has no impact on his conclusions in the report. On the other hand it can't be excluded.
Joe Bartons inquiry/Chemical industries inquiry/Fishing expeditions
I will be pleased to draw your attention to a similar action taken by the chemical industry against scientists in US. It is the chemical industry's lawsuit against Prof. David Rosner and Prof. Gerald Markowitz. The two professors have written a book about how the chemical industries and their trade organisations have tried to hide the connection between cancer and PVC/VCM and between lead pollution and health. The chemical industry is so upset over this books disclosure that they have filed a lawsuit. The layer of chemical industry went during the disposition on a fishing expedition to the files of the authors, peer reviewers, University of California Press and the Milbank Fund. This is similar to Joe Barton's fishing expedition.
In addition to this the chemical Industry has hired their own "scientist" to discredit the two professors. M&M have a similar role in their attempt to discredit MBH.
It looks like that the same master plan is behind the way the tobacco industry, the chemical Industry, the petrochemical industry and other industries are trying to discredit scientists.
The effect of these inquiries could be that no scientists want to be involved in areas where there could be a conflict with major financial interests. This could be what Joe Barton/American Petroleum Institute/ ExxonMobile/ the chemical Industry/The Marshall Institute/the tobacco Industry etc. aim at.
I find both cases interesting, fascinating and frightening.
http://www.deceitanddenial.org/intro.html
Hi KFL
Any part of the Wegman report that you can point to that is factually incorrect?
There are a lot of similarities between the way Joe Barton/M&M/American Petroleum Institute/ ExxonMobile/The Mashall Institute are trying to create uncertainty in respect of the climate science and the way the tobacco industry tried to create uncertainty about the epidemiologic methods used to assess the risk of passive smoking.
From http://www.tobaccoscam.ucsf.edu/pdf/9.6-JunkScience-Yach.pdf written by Derek Yach and Stella Aguinaga Bialous I have copied:
"The tobacco companies have carefully planned to undermine accepted epidemiologic practices and hoped that by partnering with a broad range of academic and private commercial interests, they could create confusion about the role of epidemiology and risk assessment in public policy development. The ultimate goal of the industry was to promote the trivialization of the risk of tobacco use, stating that nearly everything from eating Twinkies to crossing the street was harmful, and that tobacco was just one more "risky pleasure." "Among the notable academics enlisted by the industry are professors such as A. R. Feinstein of Yale University, editor of the Journal of Clinical Epidemiology, who on many occasions has presented the argument that the epidemiologic methods used to assess the risk of passive smoking are inadequate. In a 1992 article, Feinstein supported the tobacco industry's right to defend itself against the label of "bad guy" and criticized the "current atmosphere [in which a tobacco industry] consultant's stature, credibility, and integrity become instantly impugned and tarnished by the depravity of associating with the tobacco 'bad guy'". He did not mention, however, that he was a tobacco industry consultant and the recipient of highly secret "special project" awards".
American Petroleum Institute network is promoting the message "The climate science is uncertain", "the CO2 increase is good for the planet", "the current temperature increase is natural and not harmful" and "it will be to costly to implement Kyoto" from a shareholder value perspective.
To my understanding it is the same master plan Joe Barton/American Petroleum Industry have adopted and Ross Mckitrick, Steve Mcintyre, Fred Singer, Soon and Baliunas, and WWS have a similar role like Professor A.R. Feinstein.
In respect of smoking, it is a matter of freedom to smoke and it is a criminal act to mislead the public and to distort the science in respect of health effects. In respect of climate change, it is a matte of freedom to disagree with IPCC or with API etc, but it is a criminal act to distort the climate science in respect of the potential effect of the climate change.
If I have data that follows a sine curve (in reality) and I do an incorrect analysis on it, but nonetheless (despite my mistake) find that the data follows a sine curve does that mean the data does not follow a sine curve?
Of course not. To conlcude as much would be ridiculous.
But that's essentially what some are implying after the release of the WSS report (If you doubt this, got to ClimateAudit and read some of what is posted there.)
Even if Mann did an incorrect PCA analysis (which is by no means a given, since others [National Academy of Sciences] have reviewed his work and the WSS report was not even peer reviewed and statisticians are subject to errors like everyone else), that says absolutely nothing about whether the temperature data for the past 1000 years actually takes the shape of a hockey stick.
The whole debate about PCA focuses on individual trees and misses the greater forest. Much has been made of PCA with regard to Mann's papers, but PCA is simply a way of reducing data. Nothing more.
I suspect that this is the basic reason that WSS did not address the question about whether Mann's reconstruction of the temperature data is accurate. To do that, one has to consider actual data, rather than just considering statistical techniques (which should always be suspect, at any rate).
>Even if Mann did an incorrect PCA analysis (which is by no means a given, since others [National Academy of Sciences] have reviewed his work
Dear JB
did you read the nas/nrc report ? The bits that accepted the MBH finds hockey stick shapes in random noise ? The bits that said that MBH results require the bristle cone pines, and that bristle cones should not be used ?
And the bit that said reconstruction prior to 400 years ago have unquantifiable levels of uncertainty ?
yours
per
Per: "You did not address my main point, which was that showing Mann made errors in statistical analysis is not the same as demonstrating that his conclusions are false."
Perhaps you did not understand what I was saying, though I believe I made myself qite clear. More likley that you simply did not address my main point becasue you can not do so.
Cheers
"did you read the nas/nrc report ? The bits that" mentioned using Regularized Expectation Maximization (REGEM) to generate reconstructions and how REGEM has absolutely no requirement for using Principal Component Analysis (PCA)? What, you didn't see any mention of REGEM? Only a discussion about problems believed by a few to exist with PCA which is of zero consequence? What does that tell you about how knowledgeable that committee of "experts" is?
Hi JB
The Mann calibration was to 20th century temperature, which have risen strongly.
The proxy (Bristlecones) that most nearly matched that calibration was given several hundred times the weight on other proxies.
It so happens that the Bristlecones are not a proxy for temperature. But the Mann results follow the Bristlecone, and therefor show a disappeared or very small MWP.
Two errors you see.
1 Using the Mann method, any calibration to a rising trend will produce a result of rising trend.
2 Using the Bristlecones, and giving them several hundred times the weighting will produce a wrong result.
Per: Might I suggest you read the NAS report?
The NAS report can hardly be construed as a rejection of Mann's main point. In fact, the truth is the exact opposite.
"The basic conclusion of Mann et al.(1998,
1999)was that the late 20th century warmth in the
Northern Hemisphere was unprecedented during
at least the last 1,000 years.This conclusion has
subsequently been supported by an array of evi-
dence that includes both additional large-scale sur-
face temperature reconstructions and pronounced
changes in a variety of local proxy indicators,such
as melting on icecaps and the retreat of glaciers
around the world,which in many cases appear to be
unprecedented during at least the last 2,000 years.
Not all individual proxy records indicate that the
recent warmth is unprecedented,although a larger
fraction of geographically diverse sites experienced
exceptional warmth during the late 20th century
than during any other extended period from A.D.
900 onward."
Based on the analyses presented in the origi-
nal papers by Mann et al.and this newer supporting
evidence,the committee ï¬nds it plausible that the
Northern Hemisphere was warmer during the last
few decades of the 20th century than during any
comparable period over the preceding millennium."
[end quote]
from "Surface Temperature Reconstructions for the Last 2,000 Years (2006)" National Aacdemie Press
http://www.nap.edu/books/0309102251/html/1.html
NAS did take exception with Mann's statements about very short time periods (eg that "the 1990s are likely the warmest decade,and 1998 the warmest year,in at
least a millennium ") mainly as a result of what uncertainties**, but to characterize this exception as "rejecting his basic conclusion" is a gross misreading and/or mischaracterization of the findings of the NAS report.
**"because [as NAS said] the uncertainties inher-
ent in temperature reconstructions for individual
years and decades are larger than those for longer
time periods,and because not all of the available
proxies record temperature information on such
short timescales." -- Surface Temperature Reconstructions
for the Last 2,000 Years" -- US NAS
I google "plausible" and found:
"ADJECTIVE: 1. Seemingly or apparently valid, likely, or acceptable; credible: a plausible excuse. 2. Giving a deceptive impression of truth or reliability. 3. Disingenuously smooth; fast-talking: "Ambitious, unscrupulous, energetic, ... and plausible,--a political gladiator, ready for a 'set-to' in any crowd" (Frederick Douglass, Reconstruction [Atlantic Monthly Vol. 18, p. 764] 1866)."
Sounds about right.
Steve: What do you have against hard-drinking CA sociopaths who are on the net on Friday nights when they should be hunting for a wife? :)
Tim:
1. I agree that PC1 is not the same as the reconstruction and feel like I should get a medal for how hard I have pushed this issue (so that people practically understand it now).
2. It still bothers me that Mann has never addressed the off-centering itself. Has never acknowledged that it does mine for PC1s. That it is not conventional PCA (in any sense). That it was undisclosed. In fact, he has never said if it was intentional. I don't mind someone pointing out the effect on the recon to minimize the damage from the error. I do mind Mann's failure to adress the issue in the first place. It's not basic scientific ethics to behave in such a manner.
3. While I agree that effect on the recon is the important thing, neither MBH nor Steve nor VS nor BC nor NAS exactly HOW MUCH effect the method has on the reconstruction. (It could be imagined to have some because of the selection of a limited number of PCs).
4. This is a minor point, but the PC1 ITSELF was tauted in the text of MBH as showing the "dominant mode of variance". Given what NAS and MM have shown, this part of the text is exploded. In addition, figures 4.6 and 4.7 of Wegman report clarify how the Mannian method will mine for shapes in general out of networks. In that example: Mannian methods gives an approximation of an MWP shape from a network of one proxy and 69 noise sources, whereas conventional PCA shows more of a basic noise line.
Tim, It seems as though you're trying to make the same red herring argument about some kind of misinterpretation of the IPCC 1990 temp graphic that Gavin just made over at RC. Here's a shadow post of my response to Gavin. It applies to your post as well:
----------------------------
Gavin (at RealClimate said):
I don't think that is a point of misinterpretation by the Wegman group. They said:
Which is true. The two periods WERE widely recognized in 1990. So your claim of "poor understanding" I think doesn't hold and your criticism of their understanding is a red herring.
The essential quote is:
"This conclusion has subsequently been supported by an array of evidence that includes both additional large-scale surface temperature reconstructions...."
But the NAS Panel didn't audit any of these reconstructions. It merely assumed the assertions that they support the conclusions of MBH98-9 are correct. OTOH Steve McIntyre has already posted on ClimateAudit material which indicates that none of these studies will pass muster either. Largely they rely on Bristlecones for any support for the 20th century being warmer than any time in the past 1000 years. But the Panel explicitly states that at least strip-bark Bristlecones aren't good temperature proxies and shouldn't be used. But that's the sort of Bristlecones used (mostly) in these studies. This rather contradicts the quote above, but hey! they're into the Rodney King philosophy, "Why can't we all just get along?"
I'm not sure what the right place to post this is, but what do y'all think of science blogs? It seems rather light on:
-any right wingers
-hard core science
-traditional physical science (as opposed to enviro stuff)
In particular, Tim Lambert is a computer guy. Not like Lumo a string Ph.D.
I'm not saying any of that is wrong, btw. I think hard core discussion of physics would get pretty boring. But still why don't they have more selection?
Let me be a bit more expansive than Dano.
Even if the hockey stick is fatally flawed, there's a cornucopia of other evidence. It's important, necessary, to counter the BS in detail. However, it's also important to realize how this ultimately moves through media conduits and into the public's mind.
1) The hockey stick is a critical, central factor in the conclusion GW is real and it is AGW.
2) Scientists are in disagreement over it.
3) There's disagreement in science over the reality of GW.
Of course, it matters little who is right or proven wrong on this level. I'm just noting this. I have no suggestions how to proceed. This kind of analysis provides possible avenues to leverage the public. Persuasion industry professionals need to devise workable approaches.
If you think Gore's film is a good to great tool directed at the right audience, then consider the following. This film did not originate with Gore, the politician, nor with any scientists. It originated from a media person, wife of one of the most successful TV producer/writers of recent years. She's been sleeping with the persuasion industry, basically.
An exercise some might find interesting. Scientific American's blog has solicited global warming skeptics to vent. I haven't looked for a couple weeks, but there were three consecutive comment threads starting in March or April, and I only read the third part way. I participated in the first two. If you read them and can shut off your inner voice debating and responding and just collect data, do pattern recognition, you'll end up with an outline of Exxon's script. You've got to ignore the details as important, just record. There's lots of repetition.
You can learn a lot. About how the campaign's creators thought. Here are a few items. There's an extreme narrowness, a careful selection, of what data and research to discuss. There's some detailed, convoluted, numerical scientific memes, like focus on the hockey stick. There's also another angle. The designers knew most of the public would fall asleep with real details, so they provided a detailed script for the scientific illiterate. As George's taxonomy points out, there's a great deal of personal, professional, slanderous accusations about scientists and media. Probably more commenters cite these reasons than any other. There's not an iota of evidence presented.
Again, inferring the content of Exxon's public message [script], you can analyze the content of it and conclude important things about how the campaign designers saw THEIR job, their points of leverage. These are their tools, and counter campaigning in such areas can be highly effective. In essence, you read their minds.
A good analysis, especially with other confirmatory data, can also lead you to Exxon's rationales and some idea of what's next.
I've mentioned this in passing a couple times, but I have an analysis to share. It's a very small data set, but it plugs in to many things. There's a GW Skeptic Phase Two coming. It's outline may be visible. It may have started. I'm concerned I haven't seen it addressed. I'm also concerned that implicit in much discussion among the good guys is that the goal is public and governmental acceptance of GW and AGW. For those who may assume this in their thinking, a word of caution. Exxon et. al. will admit GW, then admit AGW, but nothing much will change. Progress will be minimal. Again my data is limited. However, it does imply something about Exxon's own goal, which also makes sense.
If it's never occurred to you there might be a Phase Two, if you've been completely focused on the recognition/acceptance of AGW and nothing beyond, consider the possibility you've misdefined Exxon's goals. In this arena, that's misdefining the problem.
Later: KFL is correct, but in a highly wonky manner. The Tobacco Institute is the paradigm but proving it is a waste of time. Such campaigns will soon become widely used because the first ventures have been so successful. There's also one mother of a campaign that no one seems to have fully seen, the radical right's shifting of the American political landscape. Proving isn't the issue, seeing is. Seeing means identifying the operational mechanisms. This then leads to accepting the need for counter campaigns on the appropriate battlefield -- the minds of the public -- with the appropriate weapons.
Therefore, the legality of such behavior is a red herring at best. Getting involved in a legal battle with someone like Exxon will only result in them sucking all the blood out of you as well as all the soft tissue off you bones. Exxon is still appealing it's Exxon Valdez damages in Alaska while some fishing communities, especially Cordova, shrivel and slowly die. The campaign has goals. The campaign has means and mechanisms. These can be understood and conclusions derived. Done properly, these point to counter strategies with a potential for success.
TCO.
Seed intentionally made these selections of bloggers. They're blogs. It's not clear if the distraction is for or from .... no personal attacks. In the industry it's called demographics.
Nice try.
Huh?
Dave Dardinger said:
"It [NAS scientists] merely assumed the assertions that they support the conclusions of MBH98-9 are correct. OTOH Steve McIntyre has already posted on ClimateAudit material which indicates that none of these studies will pass muster either."
Where is the evidence for your claim about NAS merely "assuming" things?
Where is the evidence that indicates "none of these studies will pass muster either."?
Which specific studies are we talking about? Surely you must have a detailed list if you are claiming that none of these studies will pass muster. None is an all encompassing term, so "show me the data".
Surely, you must also be aware that at least some of the supporting evidence referred to by NAS in their report does not depend on information from bristlecone pines (eg, evidence of "melting on icecaps and the retreat of glaciers around the world,").
While I await your definitive proof that "NAS assumed assertions" and that "none of the studies will pass muster" , I will attempt to come to grips with what i perceive to be your basic underlying thesis:
To see if Mann is correct, we have to have a comittee (or a blogger) audit all the other studies that support him.
Do I have that correct?
I certainly hope not, because that would be patently absurd. Science simply does not work in such a manner, whereby a large number of scientists do studies and then wait to have the official "seal of approval" stamped on their results by a committee (or a lone blogger).
If several other independent** studies support Mann's conclusions, that is reason to believe that Mann probably got it right, not reason to believe that the other studies were all wrong (and all need auditing).
**"This conclusion has subsequently been supported by an array of evi- dence that includes both additional large-scale sur- face temperature reconstructions and pronounced changes in a variety of local proxy indicators,such as melting on icecaps and the retreat of glaciers around the world," from "Surface Temperature Reconstructions for the Last 2,000 Years (2006)" National Aacdemie Press http://www.nap.edu/books/0309102251/html/1.html
Dave Dardinger, you cut that quote right at the critical part - it goes on to mention evidence that does not rely on multiproxy reconstructions.
BTW, I just got banned from CA by JohnA, after I made the point that Steve's editorial misled (in exactly the same way your editing of that sentence does) by failing to note that his criticism only apply to a subset of the supporting evidence in the NAS report. They had an excuse - JohnA jumped in with another ad hom, I told him where he could go, he banned me - but the effect is nonetheless that yet another dissenter is banned from CA, which prides itself on not banning disenters.
Posted by: KFL: "According to David W.Scoots' homepage, he is in the Exxon network. He has received funding from Exxon in the past.
http://www.stat.rice.edu/~scottdw/
It is possible, that the funding has no impact on his conclusions in the report. On the other hand it can't be excluded."
And, if we wished to use their standard for 'science', we should focus 99% of our comments on those financial links to a 'clique' of known junk science supporters.
Lee, I personally thought his editorial was fine, but think you should be allowed to state your case that it wasn't.
Barry, who cares if he has minor previous oil funding. He is a very respected senior statistician. Much stronger standing then EITHER Mann or McI. He is the real deal! Chair of the NAS panel. Did you see that CV? 100+ papers. Buncha national societies.
But who cares? Don't you have the ability to read the report, see what points are made and learn? Can't you think critically? Is it all based on who sez stuff? I mean I am in the JohnA camp in "sidedness" but I know his arguments are weak. Is it really all about appeal to authority to you? Do you read the papers? Do you have a Ph.D.? College degree? HS degree? Didn't all your teachers say that you were supposed to learn how to think?
I think I get the Seed comment now. Seed asked his buddies to blog with him. That's why it is all lefty and lightweight stuff. Not complaining. Just wondered.
But who is Seed?
JB asks "Where is the evidence that indicates "none of these studies will pass muster either."?
"none" might be an overstatement, but certainly the bulk of the evidence they gave was suspect. In deciding that Mann's conclusion was "plausible" the NAS was a bit handwavy but explicitly referred to as evidence several studies which contained the exact same problems they were criticizing Mann for. The evidence is on ClimateAudit. Um, try here, here and here to start.
Which specific studies are we talking about?These are a good start:
Crowley and Lowery 2000, Esper et al 2002, Cook et al 2004, Moberg et al 2005, Rutherford et al 2005, Hegerl et al 2006, Osborn and Briffa 2006.
TCO
I'll keep this as short and simple as possible because you're obviously ignorant about magazine publishing and, apparently, general researching. Many of these details were discussed on the Seed website at the beginning of 2006 and so may still be there. You can answer your own questions.
Seed is not a science magazine, it's a culture magazine. Anyone with some understanding of publishing, or perhaps even science, could look at the magazine and website and see this. Science is the content. Check your local newsstand and you'll see numerous publications with content that's selective of larger categories, much of it not obvious. One good way to get at this is get 6 months of issues and analyze the advertising.
Someone identified in demographic data a way to slice and dice based on identity, a sort of psychology need they could fill, the opportunity to make lots of money. The auto industry works on a similar identity-based market segmentation. The person/people with the idea either had, or raised from investors, lots of money. Lots. I won't even guess the cost these days, but a typical national magazine start-up used to expect 3-7 years until profitability. So it's many, many millions. And, as a note, it's a very ballsy or very foolhardy business venture in today's media environment. So someone is very certain of what they saw and a persuasive salesman.
They have a name for this specific demographic segment. They've likely run beaucoup studies and numbers prior and post startup. One of the marketing tools they've come up with is ScienceBlogs. There's no indication the funders, idea people, or magazine publishers are loopy, so it's safe to assume the blogs are designed to attract their target demographic to the magazine. In simple terms it's a tool, not the product.
You're asking why they would choose certain bloggers, and types of bloggers and subjects, to attract certain people to the site. Stipulating that they are executing this successfully, the specific answers are proprietary business secrets that are closely held. If you want to negotiate with the publishers the purchase of the back cover for the next ten issues, I'm certain they will explain all this in great detail. You can likely find good explanations of "publisher" on the web.
Like many lefties I see commenting on ScienceBlogs, you appear unclear about the concepts of business decision making, advertising and marketing, and return on investment. You clearly are uninformed about the magazine industry. Someone may know details beyond what I've told you, but that's a very basic intro to magazine startup and Seed's startup. Obviously, your initial thought was correct. This is an inappropriate forum to get informed answers, so beyond that your questions become transparent. In fact, you become a teaching example at that point. [Regular readers will please note that flag and remember cautions about content focus.]
A reminder -- the Seed-specific information was on the magazine's website 6 months ago. There's a search function somewhere on that site. Someone else may want to give you instructions on how to use it, but I have to shut down my computer and go out.
To clarify: what's wrong with the seven specific studies I listed is that they all relied on tree-ring data - bristlecone and/or foxtail pine - in constructing their proxies. So they don't actually constitute "independent evidence" that Mann's claim is plausible. Rather they are "dependent" evidence - dependent on data the NAS has rejected.
Which doesn't mean you might not be able to fix those other studies. Perhaps some are salvageable. The conclusions might be robust to the exclusion of the suspect data. But one would have to go investigate each of them in much the same way as Mann's to be sure. We can't simply assume the conclusions are robust. Thus, the claim that there's all this other data that backs up MBH turned out to be much weaker than it at first appeared.
What the AGW advocates seem to be missing is that if they want other scientists, and the general polulace, to accept their views, they must demonstrate their points using robust, and well accepted scientific methods. It seems pretty clear by now that the Mann et al corpus is gravely flawed.
Face it guys. Credibility has been lost. Like Bob Dylan said "I don't believe you". Its not that I deny AGW. I just don't know. But truth is that your efforts to convince us have FAILED. Your work has been found poor quality, and lacking in scientific cred.
Seems to me that is a bit of a problem if you want to be taken seriously.
Dear JB
>Based on the analyses presented in the origi- nal papers by Mann et al.and this newer supporting evidence,the committee ï¬nds it plausible that the Northern Hemisphere was warmer during the last few decades of the 20th century than during any comparable period over the preceding millennium.
"Plausible" does not meet the normal scientific standards of proof; this is scarcely an endorsement of MBH. The committee's specific conclusions on various matters show that the MBH report is not proof of anything, due to the numerous flaws that the report mentioned.
Addressing your specific point; evidence that an analysis is wrong is evidence that you cannot use the results of that analysis. The committee have shown mbh to be flawed.
yours
per
> Science simply does not work in such a manner, whereby a large number of scientists do studies and then wait to have the official "seal of approval" stamped on their results by a committee (or a lone blogger).
True. Unfortunately, the corrollary is also true; that if a committee goes through a scientists' study, and find to be crap, it very often is crap.
>If several other independent** studies support Mann's conclusions, that is reason to believe that Mann probably got it right, not reason to believe that the other studies were all wrong (and all need auditing).
one of the point that wegman's report makes is that the independent studies share proxies and authors, i.e. that at a science and social level, these are not independent.
Both NAS and wegman have identified major sources of error in the analyses used; it remains to be seen if any of these studies pass muster.
per
People need to understand that something big has happened here. This is not opinion. Not conjecture. Not politics. Not industry payola. It is fact. Plain and simple.
Not only has the iconic foundation for the A in AGW been completely demolished, which is a setback that its proponents will probably not realise for a little while, but the issue of federal funding for science projects is going to tighten up with data and methodology access requirements, and, obviously, supporting statistical data such as is required by all other fields that affect public policy.
There will be some good come from this in terms of accountability. But there will also be bad. The loss of prestige that science will suffer with policy makers due to the huge egos of a few recalcitrant scientists can do nothing to enhance funding of worthwhile, potentially controversial, projects.
>People need to understand that something big has happened here. This is not opinion. Not conjecture. Not politics. Not industry payola. It is fact. Plain and simple.
I think Jack has a point. It is fascinating to see that Mann resorts to his standard tactics of ad hominem argument; that the report was written by people "with no apparent background at all in the relevant areas".
While it may be well and good to use smear tactics against comparative unknowns such as M&M, I think the attempt to rubbish statisticians who appear to be at the forefront of US statistics may soon run into problems.
delighted !
per
Skookum: Thanks man. I will go look at more of the site, using the search function. If you want to talk more about it, that would be cool. I love to talk the bizness. HAve little publishing background. Have a very good business mind.
P.s. The "secret" aspect seems a little overdone and kooky.
A little note from the reality-based community, courtesy of Live Science.
http://www.livescience.com/
Scorching U.S.: First Half of 2006 Sets Heat Record
...
The average temperatures of the first half of 2006 were the highest ever recorded for the continental United States, scientists announced today...Scientists have previously said that 2005 was the warmest year on record for the entire globe.
It's all MBH's fault, if they hadn't published their paper, it would definitely be cooler...
Per: "Addressing your specific point; evidence that an analysis is wrong is evidence that you cannot use the results of that analysis. The committee have shown mbh to be flawed."
No, you still have not addressed my point. That's twice now.
Here's what I posted above after the first time you did not address my point:
You did not address my main point, which was that showing Mann made errors in statistical analysis is not the same as demonstrating that his conclusions are false.
With regard to this statement by you:
"one of the point that wegman's report makes is that the independent studies share proxies and authors, i.e. that at a science and social level, these are not independent."
Here's what NAS said that was relevant to this subject:
"Surface temperature reconstructions for periods
prior to the industrial era are only one of multiple
lines of evidence supporting the conclusion that
climatic warming is occurring in response to human
activities,and they are not the primary evidence."
So. Are we to assume that all such evidence is tainted by social bias? That streches the bounds of credulity, to say the least.
In the absence of proof, speculation about bias due to "social networks" among climate scientists does not even belong in a legitimate scientific conversation. It is closer to conspiracy theory than it is to science.
If you have evidence of such bias, by all means, show it to us. Incidentally, it is not enough to show that such "social networks" exist, but you must also show that they imply bias and that such bias renders invalid the conclusions of all the other studies that support mann's conclusions.
To do this, one has to do actual science, by the way.
In response to my question 'Where is the evidence that indicates "none of these studies [supporting Mann] will pass muster either"? ', Glenn Raphael posted that
' "none" might be an overstatement" '
Might be? You think? How about "definitely is"? There is no such thing as 100% certainty with regard to anything in science. Such claims basically amount to pure unadulterated hogwash.
"but certainly the bulk of the evidence they gave was suspect."
According to whom? Some blogger with no formal training in climate science somewhere?
Simply providing a couple links from a weblog (Climate Audit) is not proof that "certainly the bulk of the evidence they [NAS] gave was suspect."
This highlights a basic problem with the whole way the Mann paper is being dealt with: outside the normal scientific process, too often by people who have no formal expertise in the areas they are making claims about.
I am not referring to statistics here. I am referring to tree ring analysis and other scientific subjects that are relevant to historic temperature reconstructions.
There is a proper scientific way of adressing problems with scientific research (that has worked brilliantly for hundreds of years, by the way) and the proper way is not through web logs and congressional comittees and the like.
The way that the "issue" over the Mann paper is being dealt with has become utterly absurd, with politicans, bloggers and other nonscientists weighing in on the science in scientific areas in which they have little or no expertise.
I have no problem with people challenging others' scientific research. Indeed, that's how science progresses, but when someone does it on a weblog or in a congressional comittee it is simply not a legitimate substitute for the regular scientific process -- not even close.
JB, the comments you are responding too also reflect a somewhat common meme about what the NAS report said - and that meme is wrong. Please allow me to jump in with a bit of further discussin of the kinds of claims that you responded to here.
The NAS report's summary split the analysis into two kinds of evidence. The multiproxy reports, from Mann et al and its follow-ons, were limited by the NAS report to less than they originally claimed - the NAS committee ended up saying that the quantitative results of those analyses were solid going back 400 years, with decreasing utility because of increasing uuncertainty going further back to 900AD, and effectively unusable before 900 AD. Whel they acknowledged some statistical problems with those analyses, they also said that the primary reasons for the uncertainty were sparsity and uneven geographic distribution of proxy records as one goes further backin time. They DID limit the Mann et al global quantitative claims, but that was only one part of their report.
In the same summary, in adjacent paragraphs, they also pointed to many lines of additional evidence that independently suport the conclusion that something anomalous was going on in late 20th century climate, on at least a millenial time frame. This includes quantitative evidence from high latitude and tropical ice cores (dealt with independently because of differing uncertainties), global glacier ice balance and retreat, observations of glacial melt in places where we have evidence that it hasnt happened in many thousands of years, evidence of rooted sub-glacier plants being uncovered for the first time in many thousands of years, and so on. These lines of evidence were covered in their own chapters in the report.
The report then says that the combined quantitative and qualitative data from this additional evidence supports the quantitative claim from the Mann and follow-on multiproxy studies that temps in the late 20th century were globally anomalous on millenial time scales. They specifically said that the quantitative multiproxy claims were plausibleeven if too uncertain in thero won context, and they did this in the context of all this additional suporting data showing something anomalous happening in the late 20th century.
MacIntyre/Wegman/etc HAVE shown some data source and statistical problems with various of the multiproxy studies - and are claimign they apply to later studies but have not done a good job of extending thair analyses to all the other later reports, so that part of the cliam is IMO suspect.
But, (to get back to where I started this post) the NAS limitation and Wegman partial statistical criticism are being presented as if they cut the legs out from any claims further back than 400 years, and by some 'sceptics' as fi they cut off any claims for anthropogenic causes for climate change. This is being done in many cases by behaving as if the Mann et all work was the only evidence that existed, or at least including ONLY mentins of that work in their analysis, and that leads to implications that are simply false.
BTW, this was the point I was making, and being attacked for, when I was banned from Climate Audit.
The fact that the precise quantitative global results from the multiproxy studies have more uncertainty than previously claimed does NOT mean the millenial evidence for late 20th century cimate anomalies is not strong, even if the suporting data does not allow precise quantitative calculation of the global temps during those millenial time frames.
"definitely is" is also an overstatement, unless you're willing to point out which specific study you believe does pass muster. Otherwise you're just throwing them all at the wall and hoping one sticks, knowing most won't.
To pass muster, the study needs to (a) support Mann's conclusion(not all do!), and (b) not be tainted by methods and data sources already rejected (by NAS, Wegman and M&M so far) in the previous analysis of Mann's study.
It shouldn't require domain expertise to see this.
I'm fairly new to this topic, and checked out the Wikipedia article. It looks like it's been edited to include the results of this report as if they were completely uncontroversial.
JB, you said to per:
Your sentence above is peculiar in that you are saying that Mann had valid conclusions even if the method was erroneous. You can say he got the right "answer", but you can't say his "conclusion" was correct because a conclusion is the result of a method and there are flaws in that method. The broken clock that is right twice a day is still broken.
I understand you want to argue that AGW is still a problem. That's a fine discussion. But up to this point you are unwilling to agree that there are serious problems with MBH98. If that is the case, why should anyone bother discussing the other evidence when a NAS panel and now Wegman's report say MBH98 has serious problems. Yes the NAS panel says AGW is still a problem, just as you are. I understand you accept that part. Can you accept the part that says there are flaws in his methodology? If you do, then we can indeed move on and look at the other evidence understanding that MBH98 is not part of that evidence. If you are not concerned about errors in the methodology, then we aren't talking about science anymore.
JB
>You did not address my main point, which was that showing Mann made errors in statistical analysis is not the same as demonstrating that his conclusions are false.
I barely know how to proceed with this. We do not have godlike knowledge of what temperature was, so how can we possibly compare a reconstruction against perfect knowledge ? How then can we show his conclusions are false ?
Back in the real world, what we can show is that his method was broken. We cannot rely on the results from a broken method. It is that simple.
>"one of the point that wegman's report makes is that the independent studies share proxies and authors, i.e. that at a science and social level, these are not independent."
I am quite happy with this; the bit of the nas report you quote has nothing to do with this point, so irrelevant. I do not see why you find this even to be controversial; the relatively small number of proxies available has been commented on by the hockey-team.
When a renowned statistician makes the point that the "statistics" practiced in a small, demonstrably inbred, scientific sub-community has severe problems, and that this inbred community could do worse than take competent statistical advice, I think that is a strong criticism. And for the record, the NAS report identifies many of the same criticisms identified by Barton's committee, and makes some pretty trenchant comments.
>There is a proper scientific way of adressing problems with scientific research (that has worked brilliantly for hundreds of years, by the way) and the proper way is not through web logs and congressional comittees and the like.
Oh, let's just get this right. The NAS comittee was commissioned by- congress ! Both the NAS and barton committees are populated by- scientists ! Both the NAS and Barton committees have published findings severely criticising MBH, with substantial implications for other multi-proxy studies.
I think your theme is unsupported. There have been loads of examples of scientists who have made wrong/ outrageous/ important claims, having their work reviewed by government committees. These claims are accepted, rejected or committees aren't sure. When it comes to claims that determine public policy, it is very important to sort out what is good and bad science.
FWIW, i agree with lee that mbh is not absolutely central to theories of AGW. But i think it is embarrassing !
yours
per
Maria, just look at the number of edits in the history tab and you'll notice that this is a very very controversial lemma in wiki. See also the discussion tab.
KFL, a short note on your message of 15th July, as this is way off topic. As (now retired) worker in the chlorine/VCM/PVC industry, I have followed the debate about the "non-disclosure" of the chemical industry that VCM (the building block for PVC) is a carcinogen. Of course, when that was discovered (in animals) begin seventies, that was not trumpeted to the media, but within a few years, after it was clear that this also was the case for humans, around 1974, all (Western) factories changed equipment so that workers were only exposed to levels with very low cancer risk. No new cases of VCM related cancer were noticed for workers starting labour in VCM factories after 1975.
The chronology can be read in the chemical industry archives (linked at the Markowitz and Rosner page).
Thus if Markowitz and Rosner say that the VCM industry tried to hide that for the government, I don't think so, and even if that was the initial intention of some manufacturers, it didn't last for long. I don't think that intimidation is the best way to react on M&R's book (Greenpeace tried to shut my mouth with a process in Hamburg, Germany, didn't help much...), but the chemical industry has little to blame themselves in this case.
Btw, a process by Greenpeace against former CEO's of the Italian VCM/PVC industry for manslaughter was lost by them, as the verdict was that the CEO's did introduce all necessary measures, after the discovery that VCM is a human carcinogen.
Per: "I think your theme is unsupported."
Ah, yes, my "theme" -- that science does not work through the proclamations of blogs and committees.
Completely unsupported. Yes, indeed.
Everyone knows that science has been moving forward for hundreds (indeed thousands) of years due to comittees and blogs.
Who am I to question you opn this point?
MC, you said
I understand you want to argue that AGW is still a problem. That's a fine discussion. But up to this point you are unwilling to agree that there are serious problems with MBH98. If that is the case, why should anyone bother discussing the other evidence when a NAS panel and now Wegman's report say MBH98 has serious problems. Yes the NAS panel says AGW is still a problem, just as you are. I understand you accept that part. Can you accept the part that says there are flaws in his methodology? If you do, then we can indeed move on and look at the other evidence understanding that MBH98 is not part of that evidence.
Let me get this straight. The report says there is problem with MBH. The report also says that AGW is a problem. Now you want to accept the part that says that there is a problem with MBH, but reject the part that accepts AGW and instead move on and look at other things?
I'll make you a deal. I will accept what they say about MBH if you accept what they say about AGW.
Regards,
John
Where does it say that?
Nanny, did you read the whole post before you asked? There are actually several places where the report says that. FOr example this quote"
"It should also be noted
that the scientific consensus regarding human-induced global warming would not be
substantively altered if, for example, the global mean surface temperature 1,000 years ago was
found to be as warm as it is today."
Responding to John Cross:
I did not say I rejected the AGW references in the NAS report.
Your suggestion of deciding science by lets make a deal is novel. I suggest deciding each issue on its merits.
MC: So you are saying that you accept that AGW is proceeding as the NAS seems to think?
Your suggestion of deciding science by lets make a deal is novel.
Yeah, although I wouldn't be surprised if it happenes at times. But I only used it to make a point. However, if you are interested in lets make a deal I would be pleased to bet on future temperatures increasing.
Regards,
John
MC said: "You can say he got the right "answer", but you can't say his "conclusion" was correct because a conclusion is the result of a method and there are flaws in that method."
Ok, I stand corrected. The example that I was thinking of when I made the statement was the following:
Johannes Kepler made aritmetic mistakes in his analyis and notheless got the right result regarding the orbits of the planets.
I suppose someone somewhere might say, "Goodness, he made math errors, his work is therefore complete bunk."
But that does not change the reality of Kepler's result one iota.
For some to imply the NAS report was a "rejection" of Mann's results is simply a mischaracterization of the report.
Where is the indication of a problem in that quote?
I understand that the report does not deny AGW, but it says nothing about AGW as a "problem" as far as I read.
Nanny, I don't think that the position of the NAS is in doubt on that issue. However, to be clear, the report does say:
Consequently, their analysis enables an investigation of
the relationship between variations in climate and the frequency and severity of extreme events,
a subject that is of major societal concern in relation to projected global warming.
Unless you wish to take the position that their concern is that we will experience fewer extreme events!
I was referring to the Wegman report. My apologies as now I see that both the NAS report and the Wegman report were being discussed.
>For some to imply the NAS report was a "rejection" of Mann's results is simply a mischaracterization of the report.
did you look at the remit of the NAS committee ? It was not to come to a value judgement solely on the MBH paper, and the way it was performed. It was on the validity of temperature reconstructions.
They have said that the MBH method had statistical flaws. They have said that the MBH reconstruction for the northern hemisphere is sensitive to the exclusion of bristlecone pines (i.e. it's crap). They have made numerous other severe comments on the validity of the MBH results.
But sure, they didn't "reject" it, whatever that would mean.
yours
per
They have made numerous other severe comments on the validity of the MBH results.
I think I'm going to start calling per 'Amber'.
It's as if he's trapped in amber - why, the world stopped eight years ago and nothing has happened since the publication of a first paper!
Amber, stop stroking your totem and try to catch up with the rest of the planet, eh?
Hint: if you want to be an effective FUD purveyor, you have to do it where there are rubes.
Best,
D
It is always possible to find insignificant errors/mistakes?
I will claim that it is possible to find small errors, mistakes or lack of theory in most empirical analyses with no effect on the outcome of the analysis. There will always be assumption you can't check or data is not as well behaved as you want them to be. In addition to this most computer programs used in an analysis are moving targets i.e. you will constantly try to improve the programs in order to get better or more reliable results or to include more data in the analysis. Therefore it will not be possible in all cases to rerun exactly the same program and the same data once again and produce exactly the same results years later.
If one wants to discredit a paper on "reconstruction of temperature", "lead pollution", "PCV/CVM" etc. is only a matter of start working to stir something up. This can be done by hiring some corrupted sciencetists like Soon, Baliunas, Lomborg, M&M, WSS, etc.
The next step is to blow up these small errors/mistakes using third party organisations like American Enterprise Institute, The Marshall Institute etc using a lot of funding. This will create a lot of media attentions in the neoconservative media, which are controlled by the neoconservatives. Thus it is a matter of incest.
This is the prescription for, what we have experienced in the Hockey Stick discussion and I many other discussion.
I do not think it is OK to use this prescription.
However, I will welcome any scientific discussions within the scientific community.
Nanny: I thought that was the case (which is why I asked if you had read the post). If you do go back and read it you can see that MC's comment applied directly to the NAS. None-the-less apology accepted and consider it closed.
At the recommendation of www.realclimate.org I have been reading Spencer Weart's wonderful and worthwhile "Discovery of Global Warming" website.
One relevant observation is that of all the scientists who worked on the suite of issues, none was exactly correct on any issue, all of them simplified and speculated. Yet they measured and experimented and asked questions. They drew tentative conclusions to goad others to learn more. Slowly, usually haltingly, the ball moved forward.
Sort of like Mann et al.
PS. What are we to make of a "sack puppet"?
PS. What are we to make of a "sack puppet"?
Sock puppetry of the p*nis (apparently I can't link to the site).
Best,
D
Hi Klaus
"The next step is to blow up these small errors/mistakes"
1 They used a non temperature proxy, the Brislecones.
2 They overweighted it by several hundred times.
3 They calibrated the data wrongly to a short period rising trend, and mine for data that shows a rising trend in the 20th Century.
4 They ignored standard statistical tests, that showed the data had no "skill".
5 They republished based on similar data many times, with related authorship, and call them all independent.
6 They refuse to freely release their data and methods to third parties to test replication.
7 Mann writes his own indecipherable fortran program to do the job, when standard statistical software is available.
These are not "small errors/mistakes".
In all repects their research is fatally flawed, and wrong.
>I will claim that it is possible to find small errors, mistakes or lack of theory in most empirical analyses with no effect on the outcome of the analysis.
yes; but the issue is that the NRC and wegman panel have said that there are errors in MBH which completely change the outcome; and that is even avoiding the minor issue that Mann knew that his reconstruction failed r2, but just "forgot" to mention it.
.some corrupted sciencetists like Soon, Baliunas, Lomborg, M&M, WSS...
yes, I can see how you are a real scientist. Your attention for detail, your care for the truth; and where is the evidence to back up your claim of corruption ?
>Therefore it will not be possible in all cases to rerun exactly the same program and the same data once again and produce exactly the same results years later.
strange, because lots of other groups manage to do this. Lots of other groups archive their data and methods honestly and openly. It's not rocket science.
yours
per
Per: "But sure, they didn't "reject" it, whatever that would mean."
Perhaps I am missing the obvious in the NAS report, but if Mann's study is fatally flawed as you claim, it would seem to me that that it will be rejected by the climate science community after they take another look at it.
If "the NRC and wegman panel have said that there are errors in MBH which completely change the outcome" as you claim (though I must admit I did not read that anywhere: perhaps you could post the relevant lines?), I'm sure that some climate scientist somewhere will take another look at it.
It is exceedingly difficult to believe that everyone in the climate science community is either stupid, dishonest or "inbred" as some seem to assume (sans evidence). I am quite certain that some scientists are actually interested in and capable of finding out the truth independent of what others might be saying.
Perhaps I have a little more faith in the standard scientific process than you do, but for all its flaws, it has worked very well for a long time now. Rubbish is eventually rejected.
If you have a better system, please feel free to suggest it, but bear in mind that there are very good reasons for the current scientific process (publishing in peer-reviewed journals) and it is certainly superior to "science by blog" or "science by committee."
The problem with both of the latter is that there is no quality control -- none.
That is not to say that some blogger or statistician may not do good science and find errors in someone else's study or even discover something new. But if they do, they should publish their stuff in the peer reviewed journals like everybody else. Perhaps then it would not come down to "review at the beshest of a congressional comittee" as it has in this case.
And by the way: I simply don't buy the unsubstantiated claim that "all the reviewers are biased against individuals with no PhD in climate science and would never publish anything by them." In the absence of evidence, this is little better than conspiracy theory.
They used a non temperature proxy, the Brislecones
MarkR, would you like to go to a dendro listserv and try to argue your position there?
I'd be happy to sign you in so you can argue your assertion with people who do this for a living.
Let me know.
Best,
D
MarkR, don't forget
8. They assumed a linear relationship between tree rings and temperature, when it is well known that too hot or too cold conditions inhibit tree growth.
9. They didn't compare tree rings to local grid cell temperatures, but instead compared trees to global average temperatures as if a tree in California somehow knows what is going on globally.
(that was supposed to be #8 and #9 but for some reason they came out numbered 1. and 2. Weird.)
Dano
You already know the answer:
From Wegman:
"Although we have not addressed the Bristlecone Pines issue extensively in this
report except as one element of the proxy data, there is one point worth
mentioning. Graybill and Idso (1993) specifically sought to show that Bristlecone
Pines were CO2 fertilized. Bondi et al. (1999) suggest [Bristlecones] "are not a reliable temperature proxy for the last 150 years as it shows an increasing trend in about 1850 that has been attributed to atmospheric CO2 fertilization." It is not surprising therefore that this important proxy in MBH98/99 yields a temperature curve that is highly correlated with atmospheric CO2. We also note that IPCC 1996 stated that "the possible confounding effects of carbon dioxide fertilization need to be taken into account when calibrating tree ring data against climate variations."
Hi Nanny Govt Sucks
Sure.
I'll add them to the list.
You already know the answer:
From Wegman (etc).
I asked if YOU wanted to argue "your" point on a dendro listserv with people who do this for a living (rather than parrot something a non-climatologist wrote).
Let me know.
Best,
D
Hi Mark
Thank you for your reply to my posting.
The best reply to your remarks can be found on RealClimate.
If your points are valid scientific points of views, I am sure that Mann et Al already have included them in their analysis. I am looking forward to se the next version of Hockey Stick. This should basically end the discussion. However, the way I am reading ExxonMobile network, you and others will continue for years to discredit one of the most outstanding scientists within the temperature reconstruction.
I expect that Michael Mann will experience the same harassments like that Herbert Needleman have experienced. He is one of the leading scientists within lead pollution. He pointed out that lead in gasoline will reduce the intelligence of children. He has for years been haunted down by people probably funded by the ExxonMobile network.
It not a fair treatment of Michael Mann and it is not productive to spent so much energy and time on a eight years old paper, that qualitatively shows the same results as several other papers.
Hi KFL
Why couldn't you answer the above question:
"Any part of the Wegman report that you can point to that is factually incorrect?"
You say, "This should basically end the discussion". I notice you personally can't reply to my remarks. If you don't understand the answers, why do you have such a fixed opinion?
RealClimate don't answer any awkward quesions.
They just refer you to another web page which they say dealt with it, although in fact it doesn't.
PS And no, neither I nor most of the rest of the world work for your imaginary global Exxon world conspiracy type thingy.
PPS The best way to save the children is to spend resources on things that matter, and that are real.
MarkR
Perhaps you could give us a list of things that are real, thusfar in the unreal column we have global warming and the negative effects of lead on the developing human brain. Anything else?
But if MarkR gives us a list of things that are real, how shall we know that it is really a list? And can we really, definitively, establish the existence of MarkR? Perhaps he is the ghost of a departed quantity, to borrow a phrase from Bishop Berkeley.
I can tell you that the "Hockey Stick" is an illusion, and that money spent on the basis that it is real, is a complete waste.
Then money is real?
Teh Wegman report is biased.
The report by Wegman et al is not a scientific paper by a political manifest produced to discredit Mann et al. The recommendation 1-4 is outside probability theory, statistics, mathematics etc.
Joe Barton has hired Wegman et al as independent statistician, but no honest statistician will accept such a political involvement in a report.
The report is biased in respect of requesting a lot of documentation from Mann, Bradley and Hughes and almost nothing from McIntyre and McKitrick.
The report is biased in respect of doing a network analyse of Mann et Al and doing nothing in respect of the network around Joe Barton, ExxonMoblie and McIntyre/McKitrick.
The report is biased in respect of not investigation the huge number of mistakes and filtering McIntyre and McKitrick have done in respect of analysing the work of Mann et all.
The report is biased in respect of not setting up an alternative method for estimation and not estimating an alternative temperature curve to the "Hockey Stick". This would bring the climate science a little step forward.
The report is biased in respect of not showing the personal financial interests Joe Barton has in supporting the petrochemical industry. Joe Barton is one of the top receivers of funding from ExxonMobile.
In respect of ExxonMobile conspiracy, it is well documented, that American Petroleum Institute set up at taskforce in 1998 to start discrediting the climate science and that Exxon have spent more than 100 mills. USD in doing this. Please refer to a memo written by Joe Walker, American Petroleum Institute dated 3. April 1998:
http://www.environmentaldefense.org/documents/3860_GlobalClimateScience…
The report is biased in not using the "the principles of utmost good faith" in presenting the whole case.
Hi MarkR/Bristlecone
You have raised the question about the Bristle cone problem. On Real Climate I have found:
http://www.realclimate.org/index.php/archives/2005/02/dummies-guide-to-…
"Basically then the MM05 criticism is simply about whether selected N. American tree rings should have been included, not that there was a mathematical flaw?
Yes. Their argument since the beginning has essentially not been about methodological issues at all, but about 'source data' issues. Particular concerns with the "bristlecone pine" data were addressed in the followup paper MBH99 but the fact remains that including these data improves the statistical validation over the 19th Century period and they therefore should be included.
8) So does this all matter?
No. If you use the MM05 convention and include all the significant PCs, you get the same answer. If you don't use any PCA at all, you get the same answer. If you use a completely different methodology (i.e. Rutherford et al, 2005), you get basically the same answer. Only if you remove significant portions of the data do you get a different (and worse) answer."
Hi Ferdinand Engelbeen/PVC/VCM
To my understading the same masterplan has been used in the PVC/VCM case and in the Hockey Stick case.
You personel experience is not in line with what Markowitch/Rossner have stated in their book.
If we are going to discuss this subject, I will suggest, we find an appropriate weblog.
I love that justification! As long as the data improves the statistical validation - INCLUDE IT! Who cares if the data is a temperature proxy or not! We have data on the number of pirates in the population, Dow Jones averages, mongoose cranial measurements, whatever - INCLUDE THEM if they improve the statistical validation!
Who cares if the data is a temperature proxy or not
Do you want to argue "your" point on a dendro listserv with people who do this for a living (rather than parrot something a non-climatologist wrote)? I'll sign you in.
Let me know.
Best,
D
Dano, feel free to relay to your dendro buddies that I don't think the strip-bark bristlecones from Graybill 1993 are a temperature proxy. Let me know what they say.
Oh, yeah. And that trees don't grow so well in too-hot, or too-cold conditions, thereby making them a poor temperature proxy.
Have a good day.
Dano, feel free to relay to your dendro buddies that...
Shorter na_g_s:
I don't have the courage to argue "my" point with people who do this for a living.
Best,
D
"8) So does this all matter?
No. If you use the MM05 convention and include all the significant PCs, you get the same answer. If you don't use any PCA at all, you get the same answer. If you use a completely different methodology (i.e. Rutherford et al, 2005), you get basically the same answer. Only if you remove significant portions of the data do you get a different (and worse) answer."
If you use conventional PCA, the bristlecones are relegated to PC4 (explaining on 8% of the variance). So you have to retain four PCs to get the bristleconces into the reconstruction.
If you don't use PCA at all, and simply take the arithmetic mean, you don't get a hockeystick (this statement on RC is false). This is because the Mannian PCA grossly overweights the contribution of the bristlecones.
MBH99 does not adquately address the bristlecone issue - bizarrely, they apply a correction to the 19th century while the pulse in ring growth is apparent in the 20th century.
Rutherford et al, 2005 is similarly dependant on the bristlecones.
Dear James, "not using PCA" is not the same as "taking the arithmetic mean".
Hi Tim
I think it's evident from James' post that he knows that already.
I don't think so. Not using PCA at all [doesn't change the result](http://www.realclimate.org/index.php?p=121).
Hi Tim
From your RealClimate link:
"5) What happens if you just use all the data and skip the whole PCA step?
This is a key point. If the PCs being used were inadequate in characterizing the underlying data, then the answer you get using all of the data will be significantly different. If, on the other hand, enough PCs were used, the answer should be essentially unchanged."
From the Wegman Report (page 33):
"Figure 4.4: One of the most compelling illustrations that McIntyre and McKitrick have produced is created by feeding red noise [AR(1) with parameter = 0.2] into the MBH algorithm. The AR(1) process is a stationary process meaning that it should not exhibit any long-term trend. The MBH98 algorithm found 'hockey stick' trend in each of the independent replications.
Discussion: Because the red noise time series have a correlation of 0.2, some of these time series will turn upwards [or downwards] during the 'calibration' period and the
MBH98 methodology will selectively emphasize these upturning [or downturning] time series."
The point is, because of the Mann computation method, any data series with a correlation of 0.2 or above will produce a Hockey Stick, including Red Noise.
So to that extent, RealClimate are correct. It really doesn't make any difference at all to the result, as long as at least one of the data series, any data series, has a correlation of above 0.2.
A number of series of random data will produce a hockey stick.
The only problem is that the result will fail the statistical skill test:
"This example illustrates (if the code is correct) a situation, similar to MBH98, where the R2 statistic correctly indicates no statistical skill in the predictions, but the RE statistic erroneously indicates statistical skill.
Conclusions hinge on the choice of statistic and where you set the benchmark. MM05 obtain a critical value for RE of greater than 0.5 using random red-noise data in a replication of the procedure used in MBH98. Non-existent statistical skill of the models is one of the main arguments in MM05 against the reconstruction method in MBH98."
http://www.climateaudit.org/?p=655
That is why Mann chose to ignore, or hide the R2 test result.
All his results failed this test.
Ever wondered why Mann didn't just use a simple moving average?
Hi MarkR - a never ending story
If you will spent some time in investigating
a. the memo written by Joe Walker, American Petroleum Institute, 3.april 1998
b. the techniques developed by Edwards L. Bernays - then father of spin and public relation
c. the way M&M and Joe Barton are attacking the Hockey Stick team
d. the way many third party organisations are dealing with Global Warming
you will realize, that you are a victim of a public relation campaign.
This is to me a big surprise to se, that several intelligent and well educated individual are more or less defenceless for such public relation campaigns.
The first six lessons in public relation are:
1)The message you want to convey to the public much be simple, but not necessarily truth
2)The message must be simple to be read, simpel to be understand and soft in language
3)The massage much be understandable for the most stupid 2/3 part of the population
4)The message must focus on the inner devil or engel...
5)The message must not be directly false or at first hand not to be proven to be false
6)The message must be repeated again and again even if it is not correct
To protect the message against being unveiled by knowledgeable individuals or individuals with a high etical standards, a public relation campaign - parallel to the main campaign - will also discredit these individuals.
A public relation campaigns could be adressed to the public, to the politicians , to TV, to Radio or letters to the editors, etc.
The Hockey Stick case fits into this description:
American Petroleims Instituts message:
Global warming is harmles
Cllimate science is uncertain
Kyoto is bad for US and won't work
To protect their message from beeing unveiled they have a parallel campaign saying:
Michael Mann et al are producing flawed science
The grassroot organisations are manipulation the public
This public relation campain will continue over many years until American Petroleum Institute will realize, that it will be too costly for the shareholders not to fight global warming. Joe Bartons inquiry or similar campaigns will follow 1, 2, 5, 10, 15,.. years from now. A never ending story.
This techniques have been or are being used by the Catholic Church, The facists, The communists, The Nazzi regime, etc. After the 2.world war these techniques have been adopted by the American Corporations, The Neo-conservative, the Bush Administration, The third party organisation like American Petroleum Institute(Exxon Mobile) for god or for bad.
I am not advocating for, that these public relation techniques can't be used at all. There will be many cases where these methods to some extent could make good sense. However, there are many examples from Corporate America, where the use of these method are similar to a criminal act. The Hockey Stick case is just one example.
I think, this broader view must be included in the Hockey Stick Discussion.
KFL: So far as I can see, your analysis applies more strongly to the hockey team than it does to the sceptics!
I love that justification! As long as the data improves the statistical validation - INCLUDE IT! - nanny
Oy vey! Then what do you suppose? If the data improves the statistical validation we should IGNORE IT?
So far as I can see, your analysis applies more strongly to the hockey team than it does to the sceptics! - mbt
So why not help us see as far mtb. Do you have anything half as impressive as what Lee has offered? Or just an bald assertion devoid of any evidence? If so, why take it seriously?
"Dear James, "not using PCA" is not the same as "taking the arithmetic mean".
Tim, what, then, does "not using PCA" mean? The RC link you provide simple asserts that you get the same result. It says nothing about what this alternative method is. And if it gives the same result, why use PCA at all?
(As a footnote, the Mann method is not really PCA at all, but we can set that aside).
nanny_govt_sucks says "trees don't grow so well in too-hot, or too-cold conditions, thereby making them a poor temperature proxy.'
This statement makes me laugh out loud. Bristlecone pine trees "don't grow so well" period -- even under "ordinary" circumstances.
Anyone who has ever seen Bristlecone pines firsthand atop a windswept mountain ridge in the American southwest will know that they often grow under what can only be termed inhospitable conditions: extremes of heat and cold, poor soil, low moisture, etc.
Some of these trees are thousands of years old and are stunted to the max, often looking more like a bush than a tree, sometimes with only a few live branches.
There may be a legitimate reason not to use bristlcones as a temperature proxy but based on what I know of Bristlecones, I'd have to say that the one given above -- "trees don't grow so well in too-hot, or too-cold conditions" -- is most probably not one of them.
Climatically related temperature changes over the past thousand years are undoubtedly much smaller than seasonal (sometimes even daily) temperature changes to which the Bristlecone pines are normally accustomed.
If anything, the bristlecone pines are better adapted than most trees (indeed, perhaps all other living things) to temperature fluctuations. If they were not, they would simply not be able to live as long as they do.
My comment was about trees in general, not specifically about bristlecone pines.
Oh, Tim, in the original post you wrote:
"It would be cynical of me to suggest that the terms of reference for WSS were crafted so that WSS would only check this aspect of MBH98 and not whether it made a difference to the reconstruction."
No worries. Dr. Wegman has just said this is exactly the limit that was placed on his work and on his presence today in the committee -- that's all he was asked to do and that's all he is there to do.
nanny_govt_sucks says "My comment was about trees in general, not specifically about bristlecone pines."
That may be, but much of the criticism of using trees as temperature proxies is aimed specifically at the Bristlecones and the first post above where you made the point that "too hot or too cold conditions inhibit tree growth" was a response to/reinforcement of a post by MarkR, who states categorically that "bristlecones are not a temperature proxy".
What matters is not whether trees "generally" are not a good temperature proxy but whether the specific trees being used are good temperature proxies.
I'm not a tree expert, so I'll have to let those who are make the final judgement in that regard.
Hi Jimbo
It just means that Bristlecones are doubly useless as temperature proxies.
Jimbo,
Well, we could look at the peer-reviewed literture by the "dendro guys".
Graybill & Idso (1993) - who collected much of the bristlecone data used by MBH - concluded that the 20th century growth pulse could not be explained by temperature, and speculated about C02 fertilisation as the cause. Hughes (yes, the Hughes in MBH) stated that the anomolous 20th century growth was "a mystery" (Hughes & Funkhouser, 2003)
MarkR:
would you like to take "your" factless argument to a dendro listserv to try to defend "your" argument?
That is: do you have the courage of "your" convictions to defend them to folk who do this for a living?
Let me know.
James:
Hughes ...stated that the anomolous 20th century growth was "a mystery" (Hughes & Funkhouser, 2003)
Hence the instrumental record.
If you have citations from empirical evidence that the calibration is off because of x,y,z, please cite them.
----------
Can't wait for the astroturfers energy to wane!
Best,
D
MarkR says: "It just means that Bristlecones are doubly useless as temperature proxies."
You might be right, but I'll reserve judgement on that until I have read the papers referenced above by James and some more recent papers on the subject as well.
Folks who are confused about the "hockey-stick" wars and who want to see how deniers "pull fast ones" should google up a PDF copy of the Wegman Report and have a look at figure 4.1. A major argument used against Mann et al is that Mann's data-centering convention "mines" noisy data for "hockey stick" leading principal components. To make that case, M&M generated a big set of random noise time-series and computed principal components from it using Mann's data-centering convention. And yes, in many cases,leading principal components computed from this sort of random noise do have that "hockey stick" shape. But there's a *big* catch here, and someone with sharp eyes should have no trouble spotting it.
To see what I mean, check out the Wegman Report Figure 4.1. Figure 4.1 shows Mann's "hockey-stick" plotted right next to a "noise-only" hockey-stick. They look pretty similar, don't they? Looks pretty bad for Mann, doesn't it? But take a closer look at fig 4.1 -- in particular, look at the Y-axis scales of the two "hockey-stick" plots. You'll see something **very** fishy.