Ross McKitrick sums up the Yamal tree ring affair in the Financial Post

For those who don’t know, Ross McKitrick of the University of Guelph co-authored the first paper with Steve McIntyre debunking Michael Mann’s first Hockey Stick paper, MBH98. Ross wrote this essay in today’s Financial Post, excerpts are below. Please visit the story in that context here and patronize their advertisers. – Anthony

Flawed climate data

Only by playing with data can scientists come up with the infamous ‘hockey stick’ graph of global warming

Ross McKitrick,  Financial Post

Friday, October 2, 2009

Beginning in 2003, I worked with Stephen McIntyre to replicate a famous result in paleoclimatology known as the Hockey Stick graph. Developed by a U.S. climatologist named Michael Mann, it was a statistical compilation of tree ring data supposedly proving that air temperatures had been stable for 900 years, then soared off the charts in the 20th century. Prior to the publication of the Hockey Stick, scientists had held that the medieval-era was warmer than the present, making the scale of 20th century global warming seem relatively unimportant. The dramatic revision to this view occasioned by the Hockey Stick’s publication made it the poster child of the global warming movement. It was featured prominently in a 2001 report of the U.N. Intergovernmental Panel on Climate Change (IPCC), as well as government websites and countless review reports.

Steve and I showed that the mathematics behind the Mann Hockey Stick were badly flawed, such that its shape was determined by suspect bristlecone tree ring data. Controversies quickly piled up: Two expert panels involving the U.S. National Academy of Sciences were asked to investigate, the U.S. Congress held a hearing, and the media followed the story around the world.

The expert reports upheld all of our criticisms of the Mann Hockey Stick, both of the mathematics and of its reliance on flawed bristlecone pine data.YAMAL.eps

Most of the proxy data does not show anything unusual about the 20th century. But two data series have reappeared over and over that do have a hockey stick shape. One was the flawed bristlecone data that the National Academy of Sciences panel said should not be used, so the studies using it can be set aside. The second was a tree ring curve from the Yamal Peninsula in Siberia, compiled by UK scientist Keith Briffa.

But an even more disquieting discovery soon came to light. Steve searched a paleoclimate data archive to see if there were other tree ring cores from at or near the Yamal site that could have been used to increase the sample size. He quickly found a large set of 34 up-to-date core samples, taken from living trees in Yamal by none other than Schweingruber himself!Had these been added to Briffa’s small group the 20th century would simply be flat. It would appear completely unexceptional compared to the rest of the millennium.

Combining data from different samples would not have been an unusual step. Briffa added data from another Schweingruber site to a different composite, from the Taimyr Peninsula. The additional data were gathered more than 400 km away from the primary site. And in that case the primary site had three or four times as many cores to begin with as the Yamal site. Why did he not fill out the Yamal data with the readily-available data from his own coauthor? Why did Briffa seek out additional data for the already well-represented Taimyr site and not for the inadequate Yamal site?

Thus the key ingredient in most of the studies that have been invoked to support the Hockey Stick, namely the Briffa Yamal series, depends on the influence of a woefully thin subsample of trees and the exclusion of readily-available data for the same area. Whatever is going on here, it is not science.

Read the complete story at the Financial Post

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beng

Ross looks alittle like an academic version of Fred Couples, the Amer pro golfer.

Henry chance

So Briffa extrapolates a single tree as a thermometer. We don’t use a real single thermometer as relevant but we should use a single tree as one? A single goal won’t win the Stanley Cup in real Hockey either.

Outstanding follow up !!!

James F. Evans

You know this is a big deal by the amount of AGW cheerleaders coming on here to defend Briffa (this is the most I’ve personally seen on any one comment thread).
Apparently, Briffa has been at the center of an influential group of AGW scientists.
It must be felt that if Briffa is found guilty of “cooking the books” in the court of public opinion, the whole “science” of climate modelling will be thrown into doubt.
Yes, “holding up the scoundrel” in the course of conversation is a good “show stopper”.

Antonio San

Should have been published under “science”.

Steve in SC

He is being very polite and kind.
The simple fact of the matter is that the data was selected to support the preconceived conclusions.

Don S.

This scientific reticence will be the death of us all. Real people will starve, there will be wars, the economic losses will be unimaginable. If these allegations are true, AGW is a proven fraud. When will I read that in the paper?

Håkan B

Henry chance (07:17:10)
“A single goal won’t win the Stanley Cup in real Hockey either.”
That really depends on when you get to it!

Doug in Seattle

As a lead author of the IPCC chapter on paleoclimate, Briffa’s behavior and apparent lack of scientific rigor are especially troublesome.
I am heartened to see this scandal getting wider reporting, but there is still a long haul to go before this kind of pseudoscience gets the full public airing it requires.

James F. Evans

Steve in SC (07:30:28) :
“He [the author of the article in this post] is being very polite and kind.
The simple fact of the matter is that the data was selected to support the preconceived conclusions.”
Steve is being very polite and kind.
Briffa got caught [snip].
And this [snip] was used over and over as a supporting foundation by other scientists to justify their own papers concluding AGW is real.
A “house of cards” has had its “ace of spades” knocked out.
How long before the whole house of cards comes tumbling down?

tallbloke

Excellent and clearly written article by Ross. I don’t know how influential the financial post website is, but it seems the word is starting to spread out of the blogosphere as to how we’ve all been gamed by The Team.
Interesting times ahead, if not weather-wise.

“What makes this day different from any other day?”
Hopefully, this too shall pass.

Aron

What does Monbiot’s face look like right now? It’s bad enough at other times he looks like his raging buddies Galloway, Chavez and Saddam (now a sex slave for Satan)

Douglas Hoyt

Also highly relevant is this post:
http://www.c3headlines.com/2009/10/the-hockey-stick-global-warming-scandal-did-the-ipcc-encourage-scientific-fraud-did-the-ipcc-ignore-more-comprehensive-rese.html
It shows that 7 proxies around Yamal do not have hockey stick shapes and the 20th century is well within historic variability.

tarpon

Science goes bad when data is massaged to support a preconceived conclusion.
Great article. It’s good to have things summed up so they can be passed on to a wider community.

Pearland Aggie

Of course, the problem is that the flawed policies based on this data are already in motion despite that data being discredited. Stopping the policy implementation and future implications will be much more difficult than revealing the scientific malfeasance.

BernieZ

When are we going to realize that Climate Science is NOT a science but a bunch of folks playing with expensive equipment and then making a guess? “Climate Studies” (as it should be called) needs to go back to looking at the data and then trying to explain what they found BEFORE they adjust the data to fit their pre or should I say ill conceived theories.

Don B

Here is a general invitation by Roger Pielke, Jr. to educate Ben on this Yamal revelation:
http://rogerpielkejr.blogspot.com/search?q=

Gordon Ford

“Steve in SC (07:30:28) :
“He [the author of the article in this post, (Ross Mckitrik)] is being very polite and kind.
The simple fact of the matter is that the data was selected to support the preconceived conclusions.”
Steve is being very polite and kind.”
Canadians are always very polite and kind (Except on a hockey rink)
Off Topic – here is another article from that rabidly conservative news paper.
http://www.financialpost.com/news-sectors/energy/story.html?id=2052645
It will likely get filed under “health care debate”
PS – If the ruth were known Canadian Conservatives are probably to the left of American Democrats!

Bill Illis

If temperatures in Yamal haven’t really changed much in the 20th Century, how can one use (any select group of) tree-rings from Yamal to support reconstructions showing recent warming.
The lack of logical reasoning/basic common sense in these cases is, itself, rather bewildering, even before one gets into the statistics of manufacturing hockey sticks.
http://www.birthplaceofhockey.com/images/picorigin/mmsticks.jpg

Robinson

Excellent and clearly written article by Ross. I don’t know how influential the financial post website is, but it seems the word is starting to spread out of the blogosphere as to how we’ve all been gamed by The Team.

Try spreading the word yourself. Find an articulate summary (such as that written by McIntrick) and send it to your MP/Senator/Congressman/representative. I’ve sent one to my local MP and one to David Cameron @ conservative home (it won’t be read by him for sure, but it will get at least one extra eyeball – probably a researcher). I’m not bothering to send one to Labour home. They have a Minister for Climate Change for God’s sake. To me that sounds exactly like, “Minister for tectonic plate movement”. I fully expect a change in their policy to be about as speedy as tectonic plate movement come to think of it.

Wayne Delbeke

This may have been covered somewhere, but I am curious. If you subtract 800 from 2000 you get 1200 – so if CO2 increases follow warming by 500 to 800 years, is it possible that the Medieval Warming from 800 to 1500 is in part responsible for the increase in CO2 we see today – perhaps being released from the deep ocean? Just a question I have not seen addressed.

TerryBixler

Science has not stopped our Senate from acting foolishly. They appear to be bent on destroying the U.S. economy with more Cap and Tax based on Briffa and his tree.

Jason S

Real Climate’s response to the claim that we have been waiting 10 years from Briffa’s data:
“[Response: The russ035w data has been ‘lying around’ on the web since 2001 (at least) judging from the file stamps. And there have not been ’10 years’ of requests. That’s just crap. – gavin]”
What say WUWT? Sorry if you’ve already answered.

Alexej Buergin

I wonder what Prof. Fritz Hans Schweingruber thinks of the use of his “Schweingruber series” ?

George E. Smith

As if the validity of tree rings as temperature proxies wasn’t suspect enough; not only because of the separation of variables problem, but also the sampling statistics, particularly with core bored trees; you would think that one would want to gather as much available data from any site to show some sort of continuous history of that site.
After all, the temperature anomaly graphs from actual ground measurement stations, are each important for their own historical integrity; but there is less expectation that two different sites would fit together well, although they may both follow some major trend events.
So to me; being an ignoramus when it comes to tree rings, the integrity of the Yamal site ring data is served batter by using ALL the available trees; rather than ANY subsample of those trees, wedded with trees from some different site.
So although I can’t appreciate the fine points in Steve’s analysis; I can certainly see why why both Steve and Ross, would yell “tilt” at the way this data was originally handled.
No point in accusing Briffa of malfeasance; that is out on the limb as I see it; but it seems to me that he could have done a more scientifically clean job at the outset.
Certainly keeping the data secret for so many years doesn’t help his case.
On another matter, I see the JAXA ice graph for 2009 did finally cross back below the 2005 line; but then on looking at the DMI temperature graph, one might surmise that that dramatic temperature uptick temporarily slowed the ice expansion to allow the 2005 ice to get ahead; but now that the temperature has resumed its downward plunge, the ice curve seems to have steepened back up again.
I’m not going to propose any definitive mathematical relationship between those two graphs; but it is nice to see that they are not inconsistent with each other; and 2009 appears to be about to give us some perfectly boring normal ice expansion still heading in the direction of retreating from the 2007 low.
I have noticed the tendency of some of the regular AGW supporters who apparently work institutionally in this climate field, and post on WUWT, to belittle the comments of interested bystanders who are not active institutional researchers living off the taxpayer’s backs. Well we are simply not qualified to understand or be critical of the long established experts in the field.
The problem for those AGW supporters, is that we bystanders do no (at least I don’t) take our positions standing alone out in the park on a soap box peddling our wares.
We get our inputs from all the protagonists who are in fact equally expert researchers with long careers in this field; and on all sides of the issues.
So those who would nag at us here on WUWT, should stop worrying about what WE are saying or suggesting about climate matters; and start concerning themselves with the strong dissenting views of well recognized experts whose credentials are at least the equal of anybody the AGW supporters want to put up on a pedestal.
And the numbers of such expert workers in the field who are abandoning the AGW story in droves; is what they should concern themselves with. That is where WE bystanders are getting our clues; that the long held views that were all resolved and accepted as gospel 50 years ago; are crumbling under the revelations of modern research tools, that don’t support the religion that is still being taught in schools.
So I plan to continue to dig into the pile of rubble whenever my own credentials are suitable to the task; I’m not easily put off by the claims of those elites, who would say I should learn their witchcraft methodology first, before proposing alternative views.
George

J.Hansford

Excellent explanation by Ross McKitrick….. Keith Briffa has pretty much disgraced himself…..
In light of what we now know, due to Steve McIntyre’s persistence and diligence, there can be little denying that Briffa was knowingly hiding the data because he knew that it would show his deliberate manipulation.
This paragraph is just so damning to Briffa….. “But an even more disquieting discovery soon came to light. Steve searched a paleoclimate data archive to see if there were other tree ring cores from at or near the Yamal site that could have been used to increase the sample size. He quickly found a large set of 34 up-to-date core samples, taken from living trees in Yamal by none other than Schweingruber himself!Had these been added to Briffa’s small group the 20th century would simply be flat. It would appear completely unexceptional compared to the rest of the millennium.”

Michael

OT
Another big win. The planets must be aligning and the gods smiling down on us.
Chicago was eliminated from the Olympics.
It would have elevated Obama to god like status if they had gotten the games, but now he is confirmed to be mortal.

I’m still confused ( I’m not a scientist) maybe someone can answer this.
Concerning the Hockey Stick Chart.
Is it tree ring data before 1850 and weather station data after?

JohnM

George E. Smith (08:40:20) :¨
“I should learn their witchcraft methodology first, before proposing alternative views”
All important breakthroughs in science, art, etc. were made by outsiders.
A few examples: Famous architect Le Corbousier was the clean boy of an architec´s office, Thomas Alva Edison didn´t finish first grade school..etc,etc.
Both kind of people are needed, the discoverers and the followers, but not the liars.

Jakers

He doesn’t really say much here though, does he? What about the analysis methods? Suitability? Anything scientific at all?

Jakers

Well said George!
Down with the establishment! We are all experts now!

Jacob T

I love this website — I am not a scientist by any measure, but am a very concerned small businessman who never has bought into the AGW spin — Can you all help me out with an off – topic question — so I’m watching the news this AM, and there is Sigourney Weaver from Alien fame, and she is talking very authoritatively about the ocean absorbing CO2 and forming carbonic acid — so therefore shellfish are not reproducing, plankton are smaller and the coral reefs are shrinking — my bs antenna went up right away — so my question is, is co2 creating these type of terrible sounding conditions in the oceans ??

AEGeneral

Best article I’ve read yet. I’m passing this one on to some folks in my address book because it’s very easy to understand.

wws

This coming on the same day as Obama jumped the shark in Copenhagen is just too delicious to be believed!

DennisA

Check out the aims and objectives of British climate science in this DEFRA/Hadley contract.
http://randd.defra.gov.uk/Document.aspx?Document=GA01012_6499_FRP.doc

Joel Shore

It seems to me that Ross McKitrick’s reading of the National Academy of Sciences report on temperature reconstructions ( http://www.nap.edu/catalog.php?record_id=11676 ) is somewhat selective. For example, in the summary they say:

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 evidence that includes both additional large-scale surface temperature reconstructions and pronounced changes in a variety of local proxy indicators, such as melting on ice caps 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 original papers by Mann et al. and this newer supporting evidence, the committee finds 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. The substantial uncertainties currently present in the quantitative assessment of large-scale surface temperature changes prior to about A.D. 1600 lower our confidence in this conclusion compared to the high level of confidence we place in the Little Ice Age cooling and 20th century warming.

This statement would seem to contradict McKitrick’s assertion that “Most of the proxy data does not show anything unusual about the 20th century.”
They also make the following very important point:

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.

I am also confused by McKitrick’s statement that “two expert panels involving the U.S. National Academy of Sciences were asked to investigate”. If he is referring to the Wegman panel as the other one (which was convened by the Republican majority on the Congressional Committee), I am not sure how it involves the U.S. National Academy of Sciences. Wegman was “past chair of the National Research Council’s Committee on Applied and Theoretical Statistics” but I don’t think his role on the the panel that the Republicans appointed was in any way officially associated with the NAS.

Antonio San

joshv on the AirVent blog found this one:
Gavin quoted HALF of a sentence, in support of his claim that McIntyre is accusing Briffa of intentional cherry picking.
The half he quoted:
“In my opinion, the uniformly high age of the CRU12 relative to the Schweingruber population is suggestive of selection” (McIntyre)
The full sentence:
“In my opinion, the uniformly high age of the CRU12 relative to the Schweingruber population is suggestive of selection – in this respect, perhaps and even probably by the Russians”

Brent Matich

Good article in layman’s terms for all to understand. All this potential waste of trillions of dollars across the globe for TWELVE TREES .
Brent in Calgary

tallbloke

Robinson (08:28:01) :
Excellent and clearly written article by Ross. I don’t know how influential the financial post website is, but it seems the word is starting to spread out of the blogosphere as to how we’ve all been gamed by The Team.
Try spreading the word yourself. Find an articulate summary (such as that written by McIntrick)

I do, I do. I specialize in being a bigmouth about this stuff.
By the way, who is Mcintrick? The bastard love child of Steve and Ross? 🙂

Robinson

“[Response: The russ035w data has been ‘lying around’ on the web since 2001 (at least) judging from the file stamps. And there have not been ’10 years’ of requests. That’s just crap. – gavin]”

The file stamp is more than likely date of creation, rather than date of copy to wherever it was copied to. In any case, I suppose you could put some files up on an obscure server somewhere for all to download, only never telling anyone where they were 😉 In both cases you’re likely to be thwarted.

Doug in Seattle

Gordon Ford (08:20:51) :
PS – If the (t)ruth were known Canadian Conservatives are probably to the left of American Democrats!

As someone who has lived in both countries I can confirm your hypothesis.
For instance you will not find many Canadians, even true blue Conservative, who want to revert to a private heath care system.
On the other hand Steve McIntyre at CA has made it a point over the years to remind his more conservative readers that he is fact a liberal.
This latter fact is unknown to most AGW supporters (and foes too) here in the US.
While I usually chuckle when I read some troll drool that links McIntyre with the far right, this attribution of skepticism to the right is way off base. I know of several people personally who are “red banner” lefties that don’t buy the AGW line but support it for political reasons. I even know a few who are vocally skeptical and don’t support it.

Sad but true. The truth will only out when it is too late. The consensus rules even though it is not a consensus at all. Keep fighting for the truth. It will in any event manifest itself in the coming years but maybe not soon enough to save us all from the debilitating and potentially disastrous effects on our society.

Ray

Please help me clarify this… how many “old” trees are on Earth? Why such little sampling in such a remote area? If climate is global, could I just use the maple tree that is in my backyard (which must be 300-400 years old – it’s huge) and get my very own climate curve? On that note, maybe I would not trust that curve after all since every time it is a hot and dry summer (Fraser Valley, BC) it looses its bark.

Don Keiller

See my email to Briffa. I’m not holding my breath…
Dear Professor Briffa, my apologies for contacting you directly, particularly since I hear that you are unwell.
However the recent release of tree ring data by CRU has prompted much discussion and indeed disquiet about the methodology and conclusions of a number of key papers by you and co-workers.
As an environmental plant physiologist, I have followed the long debate starting with Mann et al (1998) and through to Kaufman et al (2009).
As time has progressed I have found myself more concerned with the whole scientific basis of dendroclimatology. In particular;
1) The appropriateness of the statistical analyses employed
2) The reliance on the same small datasets in these multiple studies
3) The concept of “teleconnection” by which certain trees respond to the “Global Temperature Field”, rather than local climate
4) The assumption that tree ring width and density are related to temperature in a linear manner.
Whilst I would not describe myself as an expert statistician, I do use inferential statistics routinely for both research and teaching and find difficulty in understanding the statistical rationale in these papers.
As a plant physiologist I can say without hesitation that points 3 and 4 do not agree with the accepted science.
There is a saying that “extraordinary claims require extraordinary proof”.
Given the scientific, political and economic importance of these papers, further detailed explanation is urgently required.
Yours sincerely,
Dr. Don Keiller.

Supercritical

Melanie Phillips in the ‘Spectator’ is saying that there is a problem with Science’s peer group process itself, which is a really huge issue.
IMO, it’s clearly a post-Enlightenment world now, and Science (at least as practiced by university staff for a living) is apparently slipping back into that region occupied by university theologists in pre-Enlightenment times.
To paraphrase an Enlightenment Joke used against those theologists and their ‘studies’ at that time; “How many angels can dance on the butt of a tree?”

PR Guy

RC’s post shows up in the Google News feed along side Ross’s article. Yet another indicator that RC has some serious PR flacks behind the scenes (presumably Fenton Communications) who know how to get a simple blog post to show up as a news story of equal weight to a Financial Post article.
Those of you who get frustrated by RC are under the mistaken impression that its a science blog. In fact, it’s a professional, highly sophisticated PR production.

Pieter F

I believe Delbeke’s observation deserves a closer look and consideration.
Wayne Delbeke (08:28:08) : “. . . If you subtract 800 from 2000 you get 1200 – so if CO2 increases follow warming by 500 to 800 years, is it possible that the Medieval Warming from 800 to 1500 is in part responsible for the increase in CO2 we see today . . .”
If that’s what the Vostock cores tell us, the rise in CO2 now has a new explanation.