UPDATE: The Climate Audit server is getting hit with heavy traffic and is slow. If anyone has referenced graphs in blog posts or news articles lease see the mirrored URL list for the graphs at the end of this article and please consider replacement in your posting. I’ve also got a mirrored article of the Climate Audit post from Steve McIntyre. -Anthony
UPDATE2: Related articles
Update: A zoomed look at the broken hockey stick
A look at treemometers and tree ring growth
===
We’ve always suspected that Mann’s tree ring proxies aren’t all they are cracked up to be. The graph below is stunning in it’s message and I’m pleased to present it to WUWT readers. I’m sure the Team is already working up ways to say “it doesn’t matter”.
The QOTW this week centers around this graph:
The quote of the week is:
I hardly know where to begin in terms of commentary on this difference.
– Steve McIntyre, Climate Audit in Yamal: A “Divergence” Problem
The graph above shows what happens to the “Hockey Stick” after additional tree ring data, recently released (after a long and protracted fight over data access) is added to the analysis of Hadley’s archived tree ring data in Yamal, Russia.
All of the sudden, it isn’t the “hottest period in 2000 years” anymore.
Steve writes:
The next graphic compares the RCS chronologies from the two slightly different data sets: red – the RCS chronology calculated from the CRU archive (with the 12 picked cores); black – the RCS chronology calculated using the Schweingruber Yamal sample of living trees instead of the 12 picked trees used in the CRU archive. The difference is breathtaking.
I’ll say. Ding Dong the stick is dead.
This comparison to CRU archive data illustrates the most extreme example of scientific cherry-picking ever seen. As Steve writes in comments at CA:
Also keep in mind the implausibly small size of the current portion of the Yamal archive. It would be one thing if they had only sampled 10 trees and this is what they got. But they selected 10 trees out of a larger population. Because the selection yields such different results from a nearby population sample, there is a compelling prima facie argument that they’ve made biased picks. This is rebuttable. I would welcome hearing the argument on the other side. I’ve notified one dendro of the issue and requested him to assist in the interpretation of the new data (but am not very hopeful that he will speak up.)
See the complete report on this new development in the sordid story of tree ring proxies used for climate interpretation at Climate Audit. And while you are there, please give Steve a hit on the tip jar. With this revelation, he’s earned it.
The next time somebody tells you that tree rings prove we are living in the “hottest period in 2000 years” show them this graph and point them to this Climate Audit article.
Here’s a “cliff’s notes” summary written by Steve’s partner in publication, Ross McKitrick:
Here’s a re-cap of this saga that should make clear the stunning importance of what Steve has found. One point of terminology: a tree ring record from a site is called a chronology, and is made up of tree ring records from individual trees at that site. Multiple tree ring series are combined using standard statistical algorithms that involve detrending and averaging (these methods are not at issue in this thread). A good chronology–good enough for research that is–should have at least 10 trees in it, and typically has much more.
.
1. In a 1995 Nature paper by Briffa, Schweingruber et al., they reported that 1032 was the coldest year of the millennium – right in the middle of the Medieval Warm Period. But the reconstruction depended on 3 short tree ring cores from the Polar Urals whose dating was very problematic. http://www.climateaudit.org/?p=877.
2. In the 1990s, Schweingruber obtained new Polar Urals data with more securely-dated cores for the MWP. Neither Briffa nor Schweingruber published a new Polar Urals chronology using this data. An updated chronology with this data would have yielded a very different picture, namely a warm medieval era and no anomalous 20th century. Rather than using the updated Polar Urals series, Briffa calculated a new chronology from Yamal – one which had an enormous hockey stick shape. After its publication, in virtually every study, Hockey Team members dropped Polar Urals altogether and substituted Briffa’s Yamal series in its place.
http://www.climateaudit.org/?p=528. PS: The exception to this pattern was Esper et al (Science) 2002, which used the combined Polar Urals data. But Esper refused to provide his data. Steve got it in 2006 after extensive quasi-litigation with Science (over 30 email requests and demands).
3. Subsequently, countless studies appeared from the Team that not only used the Yamal data in place of the Polar Urals, but where Yamal had a critical impact on the relative ranking of the 20th century versus the medieval era.
http://www.climateaudit.org/?p=3099
4. Meanwhile Briffa repeatedly refused to release the Yamal measurement data used inhis calculation despite multiple uses of this series at journals that claimed to require data archiving. E.g. http://www.climateaudit.org/?p=542
5. Then one day Briffa et al. published a paper in 2008 using the Yamal series, again without archiving it. However they published in a Phil Tran Royal Soc journal which has strict data sharing rules. Steve got on the case. http://www.climateaudit.org/?p=3266
6. A short time ago, with the help of the journal editors, the data was pried loose and appeared at the CRU web site. http://www.climateaudit.org/?p=7142
7. It turns out that the late 20th century in the Yamal series has only 10 tree ring chronologies after 1990 (5 after 1995), making it too thin a sample to use (according to conventional rules). But the real problem wasn’t that there were only 5-10 late 20th century cores- there must have been a lot more. They were only using a subset of 10 cores as of 1990, but there was no reason to use a small subset. (Had these been randomly selected, this would be a thin sample, but perhaps passable. But it appears that they weren’t randomly selected.)
http://www.climateaudit.org/?p=7142
8. Faced with a sample in the Taymir chronology that likely had 3-4 times as many series as the Yamal chronology, Briffa added in data from other researchers’ samples taken at the Avam site, some 400 km away. He also used data from the Schweingruber sampling program circa 1990, also taken about 400 km from Taymir. Regardless of the merits or otherwise of pooling samples from such disparate locations, this establishes a precedent where Briffa added a Schweingruber site to provide additional samples. This, incidentally, ramped up the hockey-stickness of the (now Avam-) Taymir chronology.
http://www.climateaudit.org/?p=7158
9. Steve thus looked for data from other samples at or near the Yamal site that could have been used to increase the sample size in the Briffa Yamal chronology. He quickly discovered a large set of 34 Schweingruber samples from living trees. Using these instead of the 12 trees in the Briffa (CRU) group that extend to the present yields Figure 2, showing a complete divergence in the 20th century. Thus the Schweingruber data completely contradicts the CRU series. Bear in mind the close collaboration of Schweingruber and Briffa all this time, and their habit of using one another’s data as needed.
10. Combining the CRU and Schweingruber data yields the green line in the 3rd figure above. While it doesn’t go down at the end, neither does it go up, and it yields a medieval era warmer than the present, on the standard interpretation. Thus the key ingredient in a lot of the studies that have been invoked to support the Hockey Stick, namely the Briffa Yamal series (red line above) depends on the influence of a thin subsample of post-1990 chronologies and the exclusion of the (much larger) collection of readily-available Schweingruber data for the same area.
MIRROR URL’s FOR MAIN GRAPHICS IN THE CLIMATE AUDIT POST:
If anyone has referenced the Yamal graphs at CA in blog posts, please use these URL’s so that they get loaded from WordPress high traffic server.
http://wattsupwiththat.files.wordpress.com/2009/09/count_comparison1.gif
http://wattsupwiththat.files.wordpress.com/2009/09/rcs_chronologies_rev2.gif
http://wattsupwiththat.files.wordpress.com/2009/09/rcs_merged_rev2.gif
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I subscribe to Scientific American, and I’m often irritated by their tendency to push agendas in politics, religion, and AGW that I find offensive and marginally scientific, if at all. I mentioned one such example recently in a comment to another WUWT article, in which the relevant SA article is here: http://www.scientificamerican.com/article.cfm?id=stumbling-over-data
The current posting strikes me as an excellent rebuttal to the above article, which portrays Watts and McIntyre as overzealous amateur scientists whose goal in life is to embarrass real scientists when the latter commit minor mistakes in data presentation.
I would very much enjoy at least a “letter to the Editor” by Anthony and/or Steve that contrasts the SA article with the facts described here in the current posting.
” Roger Sowell (21:52:39) :
Wait a minute…weren’t tree ring proxies discredited for purposes of indicating ambient temperature? Weren’t other factors found to be more important in tree-ring growth, such as precipitation? ”
Agreed, isn’t precipitation a major variable that confuses temperature estimation?
Go to http://www.cru.uea.ac.uk/cru/people/briffa/ to see who Keith Briffa is. His email address is there for anyone who wants to ask him about his work.
This is a body blow to Science. For all the wisdom spoken about how science is impartial, here is proof that papers were published to give a desired result, and not what was there.
In Australia, much is lauded by both major parties of the previous change over, many quote AGW or climate concerns. Primarily though it was labor regulation issue that drove the change. The majority of the swell, was in seats in Australia we call regional seats, outer urban or rural.
An article today in the Australian http://www.theaustralian.news.com.au/story/0,25197,26135086-601,00.html
Outlines that there is quiet concern in these swinging seats, they are by and large centrist from a policy perspective, not taking PC and other blackmail or fraud well. (the poll is on the front page of the Oz online).
There have been a series of newspolls that show trends or samples finding concern with the AGW mythology, in these centrist or marginal seats.
It is to be noted, these seats are blue collar, SME businesses, Farm or Grazing communities and sa lot of elf employed, they tend because of isolation to be people who research issues as issues. Because it their nature in self reliance, this is not to say they are right wing or anti environment. Just issues as issues.
I mention this here because in the various threads, people are not aware of an almost universal turning point occuring. I have a mate in the UK and they are not buying this AGW stuff either unless they get advantage of course.
I apol for the length of the Post, But I once debated Gavin as a bank manager would do, you have had ten years show me the money put up or shut up.
In finance if financial data is asked for and not given, this does not inspire confidence in three areas.
1. Possible Fraud or the business is on the verge of bankruptcy. 2. Incompetence or 3 the Tax mans after them for failure to provide returns, of course a fair bit of arrogance may be mixed in, 1 ,2 or 3..
At least my radio audience will know about this scandal the next Saturday and I will repeat it once and once again in my conferences… 😉
Robert Wood (20:58:35) :
What is the word for “wanker” in climatese?
[snip sorry, ad homs]
The front page of [Real]climate is still:
Communicating Science: Not Just Talking the Talk
Michael Mann and Gavin Schmidt
oh the irony!
Here here! to Jerry Lee Davis and his suggestion about getting this story out into the mainstream media.
to Phillip Bratby: According to a comment on Steve’s article at Climate Audit, Briffa is ill and won’t be answering e-mails for a while.
Please note that Briffa works in England. There is not the slightest chance of him being pulled up before the equivalent of a Senate enquiry to answer awkward questions about the use or misuse of public funds. His work is funded by the European Commission. No criticism of anything green would ever get past the Euro-cracy, given the strength of the Green Party in the European Parliament. The best chance of getting this story out in the open would be if some journalist told it in a fashion which would force the people concerned to go to court. (Merely telling the facts as they are recounted here by McKitrick could be considered libellous..)
Dear Environmentalists (both fake & real),
In recent years the strategies of the environmental movement have become too narrow & too deceitful. Without a sensible & prudent correction of course, there is the ominous risk of triggering a backlash that will leave the door wide open for an era of political corruption.
Paul Vaughan
Ecologist, Parks & Natural Forests Advocate
Clearly, the Schweingruber tree population sample suffers from that well known arborial disease ‘Hockey Droop’.
Keith Minto (22:50:23) :
” Roger Sowell (21:52:39) :
Wait a minute…weren’t tree ring proxies discredited for purposes of indicating ambient temperature? Weren’t other factors found to be more important in tree-ring growth, such as precipitation? ”
Agreed, isn’t precipitation a major variable that confuses temperature estimation?
I seem to recall a posting here, sometime last year, about a paper on a study that claimed to show that the foliage of trees maintained temperatures within a much narrower range than the ambient temperatures the trees inhabited. Since the foliage is the only part of a tree with any active interaction with the atmospheric environment, I sort of assumed that, unless this work was discredited, dendrochronologies would be pretty much a dead issue for creating temperature proxies. Although I haven’t seen much discussion of this work in the interim, I’ve seen absolutely nothing that contradicts it, yet we keep seeing works based on tree ring proxies of temperatures, which even if they weren’t full of the faults noted here would still seem to be completely worthless.
Yes this is saddening and devastating. The problem is always the same with this stuff, whether its Thompson’s refusal to publish, Mann’s refusal to supply his algorithm to Wegman, CRU’s refusal or inability to supply their raw station readings, Jones’ attempt to withhold the names of his Chinese Stations, well, lots of others.
The problem is that the conduct of the leading lights of the AGW movement is now the main obstacles to any reasonable person taking the hypothesis seriously. And, we should recall, there might be some truth to it. So it really is important to get to the bottom of the evidence.
As it is, based on this stuff, more and more people are going to simply dismiss it out of hand. Which is fine if it is totally wrong, but catastrophic if it is correct.
Here is the link for the post I referred to above;
http://wattsupwiththat.com/2008/06/13/surprise-leaves-maintain-temperature-new-findings-may-put-dendroclimatology-as-metric-of-past-temperature-into-question/#comments
Also, the Yamal proxy is the key to creating hockey stick shapes in many different papers, including the latest Arctic warming paper, Kaufmann 09.
Can we say that there is better evidence from the tree ring record now that the temperature has been dropping like a stone now for the last 20 years instead of rising? Is it also not possible that surface temperatures and satellites have been calibrated using the ‘erroneous’ data?
It may indeed be worse than we thought!
I saw this story break on Climate Audit but I hadn’t a clue what it was all about until I saw Ross McKittrick’s post which explained it. I could see that it was pretty significant though. I saw another quote there from Steve MacIntyre, on an earlier post, talking of when he was trying to figure out what was going on.
“Perhaps these 5 cores plus the 12 cores from living trees (with 6-digit IDs) are the same as the 17 cores from living trees selected in the H and S chronology. But maybe this is a coincidence. One never knows – it’s climate science. ”
Yup! That sums ‘climate science’ up pretty well.
Mann Myth Busted!
It seems to me that in fairness, Steve should have another line in the graph based on the complete Taymir data.
tallbloke (23:30:11) :
Clearly, the Schweingruber tree population sample suffers from that well known arborial disease ‘Hockey Droop’.
That should be a contestant for a quote of the week
janama (23:18:46) :
The front page of [Real]climate is still:
Communicating Science: Not Just Talking the Talk
Michael Mann and Gavin Schmidt
oh the irony!
I visited RC today for the first time in a while and would note that for the month of Sept. there is only one other post up there, a report of an attendee at World Climate Conference-3 which included the following wonderfully self-revelatory paragraph:
One concern expressed during WCC-3 was that global climate models still do not give a sufficiently accurate description of the regional and local aspects of the climate. The models also have serious limitations when they are to be used for seasonal and decadal forecasting. Climate models were originally designed to provide the large picture of our climate system, and the fact that ENSO, cyclones, various wave phenomena (observed in the real world) appear in the model output – albeit with differences in details – give us increased confidence that they capture real physical processes. For climate prediction, these details, often caricatured by the models, must be more accurate.
What a tremendous return on the billions we’ve invested in the climate modelers and their supercomputers. We should feel proud that things like cyclones and ENSO now appear as caricatures in the output of the climate models, even if they may be somewhat lacking in minor “details”, such as what, where, why, and how they appear. At least this lad sees this development as confidence enhancing for their capture of “real physical processes”. It’s no wonder the output of posts is so limited over there, they’re all probably busy at their therapists getting their Prozac dosages raised.
KimW (22:55:35) :
This is a body blow to Science. For all the wisdom spoken about how science is impartial, here is proof that papers were published to give a desired result, and not what was there.
Unfortunately I tend to agree, and it saddens me greatly. For most of my scientific career I have always pursued honesty even tho it was unpalatable to my clients. This whole temperature fiasco is disgraceful, from UHI adjustments to proxy interpretations. While proxies are useful it does appear that the “wood in the trees” problem has become a major issue. Sad.
What I can’t understand is why there isn’t an up tick of growth in all tree ring samples for the second half of the 20th century. Surely increased CO2 should have had some impact on tree growth?
Or
a) Those types of trees don’t respond to more CO2 in their diet and/or the response is very small.
b) Researchers remove a portion of the growth expansion observed to compensate (yeah, right).
c) CO2 levels weren’t as static as reconstructions suggest.
d) Some of the trees respond, some don’t.
This needs to be read in conjunction with the global temperatures to 1850, as constructed by Phil Jones at CRU. Myself, and many others here, query how they are constructed, and the value of a global temperature in the first place.
Phil Jones refuses to release the data, and as far as I understand the current situation it appears the dog ate it.
Perhaps Anthony or the moderators can provide a direct link to a couple of the reports on these topics (covered here and elsewhere) and append it to this article, as that would put this thread into a better context-especially for those readers not familiar with the whole saga-which resembles an Icelandic epic in its complexity and longevity.
tonyb
Perhaps Dr Mann is the innocent victim here, deceived from the very beginning by
unnon-scrupulous associates seeking international renown. hmmmm, or not..
The thing about tree ring chronologies is that you have this beautiful record going back centuries, millennia, and it can be absolutely dated to the year. So what can you use if for? The urge is irresistible, find something! Temperature sounds reasonable, so Mann et al have, to their fame.
Several problems, though easily ignored.
a) Trees also respond to precip and CO2 changes.
b) Trees don’t record at night or winter.
c) If I follow John Hultquist’s ‘divergence problem’ link above correctly, most trees in the study (with identical precip and CO2) didn’t even agree with each other.
When a certain ring width and density can mean either a cold, wet season, or a warm, dry season (or something in between), we’re better off dropping the tree ring temp proxy and using it for a C14 sunspot proxy.
Where’s Woodward and Bernstein when you need them?
Ray (22:27:43) :
>Pure Scientific Forgery… what happened again to that guy
>in Japan (?) when he fudge all the data on cloning? He was
>fired and won’t be able to have any grant for research…
>What about Mann now?
Hey, wait a moment Ray. The guy you mean is the deposed Professor Lee of Korea, not Japan! Maybe you Americans (?) find it hard to distinguish Koreans from Japanese by visage, but…………….