Bradley on the Hockey Stick 2
Time after time when reading Bradley's defence of the Hockey Stick, I was struck by how he avoided the criticisms that were actually made of the paper, preferring instead to knock down a series of strawmen. There are also parts that are grossly misleading.
Take this next excerpt for example, where Bradley describes McIntyre and McKitrick's Nature submission in 2004.
The authors then went on to make a similar pitch to the editors of Nature, who asked us to respond. Once they read our response it was clear that there was no point in publishing the discussion and so the criticism was rejected.
Coming after a long section in which Bradley belittles the M&M critique of the Hockey Stick, anybody reading that would surely conclude that there was a problem with the content of the M&M paper, an idea that can be assessed by reviewing the Nature correspondence.
Or what about the bit where he touches on the statistical issues:
...Detective Mann was on the case and soon discovered the reason [why M&M's result was so different]: they had not, in fact, repeated our analysis in the same way.
By changing the statistical procedure, these critics had effectively eliminated a sizeable set of data from the western United States. It was no surprise, then, that their graph was quite different from ours. Instead of a hockey stick-shaped curve, theirs was more U-shaped, with strange warm period in the fifteenth century...This flew in the face of all that we knew about the fifteenth century, a time when glaciers advanced around the world.
I suppose you can say that it is true that they had not repeated the analysis in the same way - they had of course corrected a significant error in the statistics. I leave readers to make up their own minds about how straight Bradley is being with his readers when he tries to pass this off as a failing of M&M.
McIntyre's position to on the MWP is, I believe, that he doesn't know whether there was an MWP or not, but he thinks it unlikely that tree rings will ever be able to tell us the answer. He has explained many times that he and McKitrick have not created an alternative reconstruction, they have simply shown that Mann's result of no MWP is only obtained by using dodgy data and incorrect statistics. If by processing the dodgy data in a statistically correct manner, you get a "strange warm period in the fifteenth century", that simply reinforces the point that tree rings don't have the answer.
Presumably Bradley knows this though.
Reader Comments (54)
You need to consider who the audience for this book is for the author , his looking at the already 'faithful' who want conformation of the 'faith ' and those that have some concern but little depth of knowledge on the actual subject . Its not about the science its about selling the message , its the real difference between advocacy and science , for in advocacy to tell the story in the way that best pushes the ideas you support not layout the facts in fair and equal manner .
So such trick is the norm for what they want to achieve , the only problem is the public interest in this is dropping like a stone and this is a market with lots of books pushing the same message anyway with this one just being another in long list .
KnR says it spot on this polemic is all about conformation and reinforcing of belief for the heaters Plus when did the weather in the 15th century suddenly become so well know? what with all the glaciers and cooling! they cannot even look to last year and explain that weather !
Does Bradley cover at all the process of writing MBH98? That would be an interesting story!
I mean, Mann's history around 1995-1997 is rather odd to me. A completely unknown _grad student_ (he didn't get his Ph.D from Yale until 1998 although he apparently defended already in 1996) joined forces with two big shots (Bradley, Hughes) to write a "ground breaking paper". He apparently moved under the wings of Bradley (to UMass) long before (at least in 1996) finishing his studies at Yale. Moreover, Mann's thesis advisor (J. Park) has been given no credit whatsoever in the "hockey stick stories" although the methodology used in MBH was essentially developed (with Park) already at Yale.
We have another rising star in the ilk of Dr Mann, John Abraham whose only contribution seems to that hr made a critique of one of Monckton's lectures.
As for the political intimidation bit of the title, that's a piece of brass necked hypocrisy if ever I've seen one from a man who accused another academic, who'd mentioned him 31 times in a 90 page document, of plagiarism, and suggested he' d drop the charge if said academic pulled a report critical of Bradley's work on MBH98 from the Library of Congress.
Jean
There's a little about how Bradley and Mann came to work together:
He then goes on to describe Mann applying for an Alexander Hollaender fellowship that allowed him to return to Amherst.
The bit about McIntyre having proposed an alternative reconstruction is weird. I really get the impression that people like Bradley simply do not understand McIntyre's reasoned agnosticism about tree-ring based reconstructions.
Jean again
He doesn't say much about the process of producing the paper, apart from saying that Mann did the statistics while he and Hughes chose the data.
Trees are not thermometers.
It is such flawed assertions that has done great damage to climate science.
You cannot reduce chaos and complexity of our world to such simplistic terms.
You cannot derive tales of global doom and catastrophe based on a simplistic belief that ultimately humanity is sinful.
"Presumably Bradley knows this though."
Of course he does. The whole bloody Team knows this. This is so typical of how those fraudsters twist things to make it look like good, old fashioned, honest applied scepticism is bad/wrong. I can only conclude now that all these scientists on the AGW gravy train are being wilfully misleading. Cognitive dissonance only goes so far. These people are just dirty rotten scoundrels.
Does he elaborate on "Mike's Nature Trick", the divergence problem, corruption of the peer review process, refusals to disclose data, IPCC breaking its own rules, or any of the other dodgy practices necessary to secure more tax payer funding for shonky scence?
Mac says-
"Trees are not thermometers?"
But the Queen of Hearts said they are the BEST thermometers, didn't she?
Now I AM confused.
Signed,
Alice Wonderland
I wonder what caused glaciers to advance in the 15th. century, and what caused them to stop advancing
Was it something to do with the disovery of the Americas, or is that just a conspiracy theory?
Yes, I agree with zx, KnR pretty much summarized it. Given the falling interest in the "now discredited" ( to use a warmist term) hockey stick, I don't think the publisher is going to make back the advance paid for the rights to this master piece.
That is an "inconvenient truth."
It's all on the cover of the book. Everyone but the Zombies already know that the author of the book is on the same team as the empowered political establishment.
"As the earth heated up." and cooled. And stayed the same. Funny how Warmers keep leaving information out of their declarations.
Andrew
Which evidence he quotes to affirm this?!
In the 15th Century (1400 to 1500) glaciers in the Alps were retreating!
See this chart from : Hanspeter Holzhauser, Michel Magny and Heinz J. Zumbul. Glacier and lake-level variations in west-central Europe over the last 3500 years. The Holocene 15,6 (2005) pp. 789-801
There is a clear retreat in that century, although less than at present and much less than in the Viking and Roman eras.
Bish, you quote Bradley:
As I pointed out in this post, when cancer researcher Anil Potti and co-authors were confronted with errors and non-reproducibility of their work published in Nature Medicine, they wrote back:
I believe the rule is simple: if your work uncovers a fundamental aspect of reality, it should hitherfore be less sensitive to the nature of the method used to uncover it. The extreme specificality of an experiment, in most instances, robs an experiment's conclusions of its more general application.
Andrew:
Is this book worth buying or should I wait until it shows up in my local library system?
Bernie
Suggest you wait until its discounted price makes it economical to use as a firelighter
Jeremy, there can be little doubt that Bradley understands McIntyre's position perfectly well. See David UK's comment which regrettably provides the only plausible explanation.
Does Bradley mentions his well known habit of borrowing text? E.g. taking various parts of Frittz, 1976 for Bradley's 'own' book. Here extensive portions were copied word for word (except that Bradley deleted the inconvenient, but well established notion that CO2 (as well as temperature) increases tree ring widths.
See http://climateaudit.org/2010/10/20/bradley-copies-fritts-2/
ZT,
And I am sure that "when glaciers advanced around the world" is lifted directly from an H.G. Wells short story.
BH
"He doesn't say much about the process of producing the paper, apart from saying that Mann did the statistics while he and Hughes chose the data."
Interesting, so the choice of strip barked bristlecones was down to Himself and Hughes. Does he justify that choice;)
"preferring instead to knock down a series of strawmen."
Maybe Obama's teleprompter helped him write the book?
Eddy
No, he doesn't mention the bristlecones at all.
@simpleseekeraftertruth
I wonder if action will be taken over this brazen theft from Pachauri's masterpiece?
"[McIntyre] has explained many times that he and McKitrick have not created an alternative reconstruction"
This is something that Ive been meaning to ask about for some time. Why ? Could somebody please point me to the relevant links that explain why there is no alternative recon, what page in HSI deals with this ?
ZT. :-))
"why there is no alternative recon"
Hengist, because climate science doesn't provide any reliable method of making one to begin with.
Andrew
Thanks Bad Andrew and thanks Bishop Hill for telling us no reconstruction acceptable to skeptics exists , something I'd been wondering about. I'd be interested to read the esteemed Mr McIntyre's explanations (referenced above) does anybody have a link to the relevant posts at Climate Audit?
More than twelve subsequent scientific papers, using various statistical methods and combinations of proxy records, produced reconstructions broadly similar to the original MBH hockey-stick graph (from wikipedia ) so perhaps the skeptic narrative would be strengthened if an alternative recon was offered .
Hengist McStone
"...explain why there is no alternative recon..."
You may have heard an analogy like this before but I don't see why it still isn't a good answer to this question - if you are known as a debunker of every photo of UFOs that appears and then some ufologist turns round exasperated saying "Well where are your photos of the lack of UFO's!" you might get the idea? ;)
I think some (like me) on the sceptic side take the opinion that there is no existing powerful proxy method to show temperature back a thousand years in a useful way. It may well turn out there will be some tangible scientific breakthrough as yet uninvented/discovered that changes that, but until then, statistics is being brought to bear to torture the data and Steve M just shows how that is being done with too high a claim of power. So McIntyre just doesn't claim to do reconstructions himself because that would be to indulge in tea leaf reading himself ;)
Hengist
I don't want to put words into Bad Andrew's mouth but I think what he was saying was that there was no way to do a reconstruction because there was no proper construction in the first place.
MBH98 was a crock. McIntyre didn't need to produce any construction of his own, just prove that the statistical methods used to give Mann, Bradley and Hughes their results would have thrown up the same answer if they'd used the Caithness telephone directory.
I don't need to have a countervailing hypothesis in order to prove yours has flaws, something that climate scientists (if indeed they are scientists) know perfectly well as should you if you are a scientist.
Are you a scientist?
In the Little Ice Age men wore long frock coats, trousers, and tall hats (so the caricature goes) and in the Tudor period (more strictly 16th than 15th century) there was a distinct contrast. Men wore hose, stockings up to there little short puffed out pantaloons or whatever they were.
In the Little Ice Age men wore long frock coats, trousers, and tall hats (so the caricature goes) and in the Tudor period (more strictly 16th than 15th century) there was a distinct contrast. Men wore hose, stockings up to there little short puffed out pantaloons or whatever they were.
Hengist - random data produces a hockey stick thanks to Mann's statistical methods and malfeasance. There's a concise summary here:
http://a-sceptical-mind.com/the-rise-and-fall-of-the-hockey-stick
Mann's Hockey stick has been discredited for years now, do try to keep up.
dnftt
HM:
Yes, there have been various reconstructions using different techniques and proxies, except there is usually a problem with the way most of them have been done. Basically any reconstruction that uses, stripbark bristlecone pines, yamal treerings, or tiljander sediments is suspect right from the word go. Each by themselves can cause a reconstruction to look like a hockey stick. I can't remember by name the ones that use those, but a check of the 12 on wikipedia and I will bet most if not all will have one of those 3 included.
You will see some people trumpet that the reconstruction still gets the same conclusion without yamal, but will have tiljander, or the result is the same without tiljander and yamal, but will have bristlecone pines. Some authors will come up with any excuse to use at least one of those.
So when you see an author state that even with the correct statistics, the results are similar to the original, you must remember that even if the math is right, the data may not represent what the author thinks it does. As with the original hockey stick, bristlecone pines should never have been used to represent temperature because of the way the tree itself grows and the way the samples were collected. So it doesn't matter if you used the most perfect statistical method in the world, the results are not correct because the data it represents is false. Yet bristlecones are still being used in reconstructions despite knowing that they should not be used.
Last, to answer why skeptics don't accept the reconstructions is that there is no proof that they are representing the same thing today as they did in the past. In other words, to regard a proxy as representing temperature, you have to make a lot of assumptions. Some assumptions are untestable, so you just have to take it on faith that the conditions today are similar to those in the past. Other assumptions that can be tested are frankly just laughable. Tiljander treerings do not match local temperatures. Only by including temps from farther away do the rings correlate better (teleconnected). One would think local conditions are more important than those 1000 miles away, but the assumption is that the treerings are better represented by including temps from areas farther away.
Since the assumptions made to create a reconstruction have a huge potential of altering the results (which are not represented by the statistics) AND if every sceptic agreed to the assumptions (which by definition a sceptic would not do) then whatever reconstruction that is created could still be wrong. Saying you agree with an assumption does not make the assumption true. The best you could do would be to say "this is our guess but it is possibly wrong". Which doesn't really strengthen anything.
Anymouse, my experience is that many people do not understand things that seem perfectly obvious to others. Now, you can ask interesting questions about cognitive dissonance and subconscious desires not to understand things because of some sort of feeling that it might not be desirable to understand. But outright intellectual dishonesty is - in my experience at least - rare.
Referee #3 didn't seem to understand the MM argument at all, thinking that they were presenting an alternative reconstruction as evidence of past climate rather than as evidence of bad science. However he ends up with the right answer, that both analyses are junk. Which was MMs point. It must be frustrating when a referee doesn't understand what you're arguing
"Considering the changes relative to the first version of MM04, it seems to me that the case presented by MM04 has weakened considerably. The main claim presented in MM04 is now that the main features of MBH98 reconstruction (the hockey stick) derive from two methodological aspects. Now, no preeminence is given to the 16th century being warmer than the 20th century. MM04 have emulated the MBH98 reconstruction improving the methodological aspects that they think are flawed, and arrive to another reconstruction that yields rather low values of RE as verification statistics. They claim that MBH98 reconstruction has also low values of another verification statistics (R2), and therefore conclude that MBH98 is therefore on equal footing as theirs. Accepting this line of reasoning, however, a reader of these manuscripts will be led to think that both reconstructions are not trustworthy (at least, I would not trust any reconstructions with such low values of verification statistics, table 2 in MM04 supplementary material)."
@Mike Jackson
No I'm not a scientist, I don't know where you get that idea. You're right when you say " I don't need to have a countervailing hypothesis in order to prove yours has flaws, " but proving flaws in science is part of the process of improvement.
@Leopard in the Basement
"I think some (like me) on the sceptic side take the opinion that there is no existing powerful proxy method to show temperature back a thousand years in a useful way."
I think you've hit on something there. I'd like to ask for falsification of that view in other words when would a millenial temperature reconstruction be 'useful'.
@Iapogus
I was hoping for a link to Mr McIntyre to support the statement above by Bishop Hill
Gentlemen , it's agreed on all hands that there are problems with Dr Mann's work. But that or the twelve other reconstructions we have is our best guess. There is no alternative offered by the skeptics, I accept that. What the skeptics can say is that Mr McIntyre has explained why not, I'd still be very interested to read his words.
Hengist, have you considered reading his blog? There's a few key posts that are highlighted, so someone of your skills should be able to find your way very quickly...
Hengist Stone
I really myself can't talk with authority about an as yet unrealised future ;) But I will say I am hopeful that it may happen (though there is no reason to assume it would ever). My best guess is that a breakthrough in reconstruction would require, as I said earlier, "tangible scientific breakthrough as yet uninvented/[un]discovered"
HM -
For a quick view, you might try this. For a more comprehensive view, there's this, which unfortunately is rather a kitchen-sink list of relevant papers.
Of course, I can also recommend our host's work, see the sidebar. But you knew that already.
Hengist, you know in scotland they have a legal verdict called "not proven"
Well that is the best description of climate science and especially the reconstructions described above.
Or in more simple terms, these reconstructions are b*llocks. That's why they had to chop off the data after 1960. Remember "hide the decline". This is what McIntyre has been showing for years. The whole thing is a disgrace to science. One day people will write about this as a dark period for science.
Quite frankly, I doubt tree rings will ever be able to provide a solution. The combination of inputs that result in an output (the ring width) is likely not stationary (implying non-linear as well,) and immediately eliminates linear extraction techniques from applicability. Oh well...
Mark
Nobody can doubt the world has at all times a mean average temperature. Over time that temperature fluctuates . How has it fluctuated over the last 600 or 1000 years? Only the warmists have come up with an answer to that one.
I don't doubt that Mr Montford is correct when he says that " [McIntyre] has explained many times that he and McKitrick have not created an alternative reconstruction," but you guys are more familiar with the work of Montford and McIntyre than me. I'm just asking for support for that remark ie one of Mr McIntyre's many explanations. Or where is this discussed (if at all) in the Hockey Stick Illusion?
Hengist
I simply asked if you were a scientist. Thankyou for the reply.
As for tree rings, ask a dendrologist about them. I think you will find that the only thing you can tell from tree rings is the age of the tree (and I believe that is not 100% certain). There are myriad weather conditions apart from temperature which affect the thickness of the rings.
Anyone who uses tree rings to deduce anything about climate patterns over the last 1000 years would, it appears, be asking for trouble.
(Only a cynic would suggest that that is why a wet-behind-the-ears post-grad-soon-to-be-PhD had his name stuck up front on a paper whose main purpose as far as I can see was "get rid of the mediaeval warm period". I think the wee mann was set up.)
so Hengist, you want a quote from McIntyre to explain that he has not made an attempt to make up a historical picture of the Earth's temperature for the last 1000 years. Why is this so important to you?
If you want a direct quote from McIntyre, why not go to the climateaudit site and ask him?
Here is a list of some studies of the junk behind the various "hockey-sticks"
http://climateaudit.org/multiproxy-pdfs/
Here is a link to an analysis that shows that one set of proxies was not merely removed from the plot after 1960 but was also ignored prior to 1550, without the latter being discussed anywhere. The proxy reconstructions are basically junk. Maybe in about 900 years' time, we will be able to report on the climate of the last 1000 years.
I refer you to Paul Dennis's comment:
Paul Dennis
Posted Jun 10, 2011 at 1:32 AM | Permalink | Reply
I entirely agree with your last paragraph Steve. We are not going to make much, if any progress, in determining palaeotemperatures until we have good constitutive models for the response of proxies to temperature. Such models will allow us predict a-priori the sign of a response with ,for example, an increase in temperature. What we have at the moment are crude phenomenological descriptions in which the phenomenology is allowed to change over time.
on this thread:
http://climateaudit.org/2011/06/09/mcshane-and-wyner-weights/#comments
and here is an elegant essay by Willis Eschenbach that ought to demolish the credibitly of all these proxy reconstructions
http://wattsupwiththat.com/2011/05/30/kill-it-with-fire/
missing link to the deletion of data pre 1550
http://climateaudit.org/2011/03/21/hide-the-decline-the-other-deletion/#more-13308
Bradley seems to suffer from astonishing naivety. "Climate Science", or its political interpretation, seems to be calling for the de-industrialisation of the world's developed economies. Finding the opponents of this policy playing hardball has taken him by surprise and he is shocked and offended.
I guess some people move smoothly through the education system, destination: ivory tower.
"Climate Science", or its political interpretation, seems to be calling for the de-industrialisation of the world's developed economies
Decarbonisation and deindustrialisation are not necessarily the same thing and to insist that they are is both distorted and unhelpful.