Mann's 'hockey stick' claims of the MWP and LIA being local were refuted years before it was published

IPCC TAR WG1 (2001) summary, “Figure 5: Millennial Northern Hemisphere (NH) temperature reconstruction (blue – tree rings, corals, ice cores, and historical records) and instrumental data (red) from AD 1000 to 1999. Smoother version of NH series (black), and two standard error limits (gray shaded) are shown. [Based on Figure 2.20]”. Adapted from the MBH99 graph which Jerry Mahlman nicknamed the “hockey stick”. Image: Wikipedia

Pierre Gosselin at NoTricksZone reports:

Geologist Dr. Sebastian Lüning and Prof. Fritz Vahrenholt found a Japanese tree-ring temperature reconstruction from 1995, one that should have been heeded by the IPCC and Michael Mann before they took the world on a 10-year joyride in the stolen car of “climate science”.

Here’s the Google translation of their article, with some fixes of my own to help it along written in [brackets]. I don’t vouch for total accuracy in the translation, but it is the best I can do.

UPDATE: 2:45PM PST Pierre Gosselin has graciously agreed to allow his translation to be posted here, so I’m eliminating the Google translate version – Anthony

Medieval Warm Period and the Little Ice Age as a local, North Atlantic phenomenon: Since when is Japan located in the North Atlantic?

By Sebastian Lüning & Fritz Vahrenholt

(Translated and reposted here at WUWT with permission, copyright English text NoTricksZone)

Leading representatives of the IPCC tried for years to have policymakers and citizens believe the pre-industrial temperature history was more or less uneventful and was the ideal climate ondition that we should all strive to maintain. The warming of the 20th century, on the other hand, was completely unusual, something dangerous. However, as we now know, the page turned a few years ago and the notorious Hockey Stick chapter ended. The flawed curve was taken off the market and the Medieval Warm Period and Little Ice Age reappeared. 

As is often the case in history, it is in retrospect difficult to comprehend how this historical joyride could have happened to begin with. It started at the end of the 1990s with a doctoral thesis by Michael Mann, and did not end until about 10 years later – thanks to the discovery of the scientific scandal by Steve McIntyre and Ross McKitrick (see the book The Hockey Stick Illusion by Andrew Montford). Today it is difficult to fathom how the main players and proponents of the Hockey Sticks are still able to act as experts and public opinion shapers.

One of the main excuses used back then was that the Medieval Warm Period and Little Ice Age in Europe and North America were local phenomena. At other locations on the planet the temperature anomalies were more than evened out (e.g. Stefan Rahmstorf, Gerald Haug). For years we had to listen to their tales and we had to trust these “specialists” for better or for worse. Moreover, we paid them with our tax money so that they could deal exclusively with the climate and carry out the tedious work all this entails.

However, anyone who knew a little something about the scientific literature soon began to wonder. The Medieval Warm Period and the Little Ice Age as a local North Atlantic phenomenon? A nutty claim. Naturally these characteristic temperature fluctuations had been described for other parts of the world. Here we report on a case study from Japan which had appeared in the Geophysical Research Letters already in 1995, in other words, in the years before the Hockey Stick episode.

In the early 1990s, Japanese scientists Hiroyuki Kitagawa and Eiji Matsumoto extracted eleven tree ring cores from cedars on the South Pacific southern Japanese island of Yakushima. The cores contained tree-rings going back some 2000 years. The researchers determined the carbon 13 isotope values and found the delta-13-C values fluctuated in a characteristic manner (see Figure 1).

Figure 1: Temperature reconstruction for the island of Yakushima in southern Japan on the basis of carbon-13 isotopes. Note: Temperature axis is mirrored: cold temperatures upwards, with warm temperatures down. Figure supplemented by Kitagawa & Matsumoto (1995) .

What did these fluctuations mean? Carbon-13 amount is influenced by a number of factors, among them temperature. The Japanese scientists calibrated the isotope development on trees of different elevations (and thereby temperature level) above sea level. Using this method they were able to come up with a formula that could be used for computing the temperature value using the isotope change. The results showed that temperatures over the previous 2000 years in South Japan fluctuated over a range of 5°C. The course of the temperature fluctuations takes on a shape that is very well known to us (see Figure 2). A clear millennium cycle is depicted. The cold period of the Migration Period, the Medieval Warm Period, the Little Ice Age and the Modern Warm Period are clearly recognisable. Moreover, this climate development is well documented in Japanese historical records.

Therefore, it is incomprehensible that with the clear Japanese data from the year 1995, the talk of a “local North Atlantic phenomenon” would go on for years after the data’s publication.

Figure 2: The same curve as in Figure 1, but mirrored (up hot, cold at bottom) and marked with the historically known warm and cold periods.

The two Japanese scientists even took it a step further. They carried out a detailed frequency analysis of their data and found characteristic cycles with periods in the range of several decades and centuries. Among others, they discovered a period of 187 years, which coincides with the known Suess/de Vries solar activity cycle. In a similar manner the 70 and 89-year Gleissberg-cycle was identified. In their results the authors saw a clear sign that the climate of the last 2000 years in southern Japan was predominantly influenced by solar activity fluctuations. The IPCC appears not to have been at all interested in the study. Indeed it did not fit with their climate catastrophe picture.

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NOTE: Commenter Peter Gulutzam made this observation in comments. The original Google translation correctly noted “…the southern Japanese island of Yakushima…” but Gosselin’s version incorrectly identifies it as a South Pacific Island. I’ve made the correction and notified Mr. Gosselin – Anthony


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Otter

I made a point of linking to this, as soon as I saw it at P. Gosselin’s page. Expect the usual drivel from stokes, connolley et al. They’re most lazyteenagers, after all.

kim2ooo

It’s a shame this is still “paywalled”.
http://www.agu.org/pubs/crossref/1995/95GL02066.shtml

The desire for a global social, economic, and political transformation relied first on freezing, then on warming, and now on biodiversity. Whatever argument is plausible until thoroughly refuted. Plus now the schemers are hard charging on using education to change human nature to induce desired behavioral change.
Look at page 8 of this link:http://www.stakeholderforum.org/fileadmin/files/PAPER%202_BEYOND_GDP_Final_vj%20%282%29.pdf
This New Economics Foundation is still transitioning but nef is certainly causing plenty of trouble in the UK.
Plus no good will come out of Ford Foundation backing for this. They will have their social change whatever theory they have to use.

Why am I not surprised?
Thank you for this. MWP is critical to a reasoned, non-alarmist approach to climate. Leaving it out, straightening the handle, is, in many ways, more important than finding a big 20th century blade. “Unprecedented” warming is the only thing which will provoke a policy response. Mann delivered and, sadly, we have wasted many billions of dollars on lame policy responses to what increasingly appears to be a non-problem.
More studies like this one will, I hope, make the lunacy of carbon taxes and windmills more and more difficult to sell to an increasingly skeptical public.

There is relatively good agreement with Loehle’s global temperature (green line) as well as with mine Northern Hemisphere geomagnetic (blue line) reconstructions
http://www.vukcevic.talktalk.net/JLMrecon.htm

davidmhoffer

I was about to poo poo this as another tree ring study, but then I noticed they didn’t use tree ring width they used C13 to correlate to temperature. OK, suddenly the study has credibility in my eyes. But doesn’t this beg an additional question?
Would this technique not be valid for other tree ring studies?
Not that Mann or Briffa or Jones would actually make their cores available for study….

Note to Nick Stokes — before you say anything, the positive numbers are *below* the line in Figure 1…

Have a look at the wiki entry for the Migration period for a laugh about the absurdist use of “global warming” http://en.wikipedia.org/wiki/Migration_Period

Bloke down the pub

Ah so. those inscrutable Japanese have one up on Mann.

cui bono

Thanks Pierre, Anthony – great stuff. Elsewhere,the Law of Unintended Consequences: Gergis et al seem to have everyone producing hockey sticks from statistical thin air: Lucia is having fun over at the BlackBoard, and RomanM at Climate Audit. It seems a game for all the family. Sadly I lack enough stats to contribute, but following the arguments is good fun.
Stamp ‘Rosebud’ on a hockey stick, and burn it.

Without the hockey stick, of course, the whole AGW proposition, that we’re in a state of abnormal runaway warming, is a joke. Current temperatures are normal. The climate is fine.
The two central necessary non-elective foundations of AGW theory have been debunked: the hockey stick, and on CO2. Yes, the greenhouse theory on CO2 as presented by the ipcc has also been refuted. Totally refuted, and the ipcc has not gone back to the drawing board and presented any alternative. Before 2000, the ipcc tried to make the case that CO2 affecting climate temps is “settled science” by positing a causal correlation between CO2 and temps… but this is a specious false correlation (not causal). So, the very foundation of the ipcc’s claim for CO2 driven climate warming has been repudiated. Yet, see algor repeat this monstrous deception in this must view and share 3 minute video: http://www.youtube.com/watch?v=WK_WyvfcJyg&feature=player_embedded

Anthony, Pierre Gosselin has a text version that I find both clearer, more legible, less ambiguous, and richer. Can you replace the one here with his?
Excellent article. Thank you very much. Hope Steve reposts it. Good to see trees used reliably, sensitively, and productively at last:
(a) isotopes not treerings
(b) calibration with trees at different altitudes
(c) search reveals the presence of solar cycles – Suess and Gleissberg cycles.
REPLY: No, I can’t as he has prominently placed a copyright to his translation right at the top of his article. He doesn’t allow reposts without explicit written permission, so Google translate is the best I can do. – Anthony

Reblogged this on Public Secrets and commented:
So, the IPCC probably knew about this research, but chose to ignore it because it didn’t fit the preferred alarmist narrative. The dishonesty of the global-warming crowd is astonishing.

The MWP and LIA have been well established throughout the world. http://pages.science-skeptical.de/MWP/MedievalWarmPeriod.html
We really should just start laughing at these people. I mean, sure, it’s good to trip back down memory lane from time to time, but we should use this for ridicule and scorn.

KnR

Its always been an oddity that although the alarmists will tell us the MWP does not have enough evidenced to support the idea it was ‘world wide’. There more than happy for a far more restricted range of evidenced, indeed down to ‘one tree’ at times , to be more than enough to support the claim of climate doom. As with such much of climate science that cannot meet their own low standard , but then its ‘different ‘ when they fail , like a good politician is a strong belief in do what I say not do what I do .

Jack

STOP THE PRESSES! STOP THE PRESSES! Hockey Stick proves we will all die.
Buried somewhere between ads for tinea and the death notices. Hockey stick wrong!

Andrew

why is this site listed as lukewarmer here?
http://www.accuweather.com/blogs/climatechange/Science
Its obviously 100% warmist. I think that by giving it a lukewarming status you are assigning it a respect it does not deserve. Please consider putting it in the same category as RC or like.

This isn’t the only evidence re Japan; the Emperor’s gardener kept careful records of the cherry blossom’s blooming day — going back for a millennium. They also confirm the MWP.

d13C doesn’t necessarily have the same problems as TR width, so this may be a useful new class of proxies.

Pamela Gray

I could go up into the Cascades or the Blue Mountains, core a dozen or so trees, some near water, and some up on the hill just yonder, some spaced apart, and some crowded together, some on the East slope and some on the West slope of that draw, and prove any kind of temperature graph you want me to prove. The true stories of tree cores are best left to private foresters, who know quite well how to read them. These are folks climate scientists have no knowledge of. They grow trees for profit. That is if they are any good at it. If they aren’t, the President of the University will not be coming round to bail them out of the mess they will find themselves in.

tonyb

Bearing in mind that we pour scorn on Manns tree rings as being an unreliable proxy for temperature for a myriad of reasons (limited growing season, susceptibility to local micro climates etc) we shouldn’t rush in to praise this study just because it tells us what we want to hear.
IF the methodology of using C13 to correlate to temperature is considered so accurate, as others say above, why don’t we apply it to other tree ring studies-such as Manns? Sorry, tree rings might be just about acceptable at dating or demonstrating moisture levels in the summer, but a global thermometer accurate to fractions of a degree? I don’t think so.
tonyb

Dan in Nevada

omnologos says:
June 17, 2012 at 11:33 am
You must be referring to “The causes of this cold [migration] period are debated, but are generally attributed to the lack of global warming.”
You’re right; hard to wrap your mind around something that profound.

AllanJ

One of the important reasons they had to do away with the idea of a global MWP is the “tipping point” concept, The concept that we are near some magic global temperature that will tip us into positive feedback and disaster.
If the earth has previously exceeded the “tipping point” temperature without going into positive feedback much of the scary argument is weakened.

Dan in Nevada

tonyb says:
June 17, 2012 at 1:56 pm
tonyb, very well-stated cautions. The point of the article, though, was that there existed a study that looks to be at least as robust as Mann’s (arguably more robust since there doesn’t appear to me to have a decline requiring hiding) that was pointedly excluded from consideration by the IPCC and their warmist supporters.

DirkH

tonyb says:
June 17, 2012 at 1:56 pm
“Bearing in mind that we pour scorn on Manns tree rings as being an unreliable proxy for temperature for a myriad of reasons (limited growing season, susceptibility to local micro climates etc) we shouldn’t rush in to praise this study just because it tells us what we want to hear. ”
Mann did not just take some tree ring width data and interpreted it; he ran it through an algorithm of his own making to get the result he wanted. And then he invented Mike’s Nature Trick To Hide The Decline to get rid of that “divergence problem”. There’s so much wrong with what he did that it would be an extraordinary claim that any other proxy study is only half as wrong.

DirkH

Andrew says:
June 17, 2012 at 12:50 pm
“why is this site listed as lukewarmer here?
http://www.accuweather.com/blogs/climatechange/Science

It’s a remnant of the days when Joe Bastardi was there. Yes, it should be recategorized now.

edcaryl

Anthony,
Check your spam filter. Pierre sent you permission.

Latitude

A tree sequesters C13 just like it makes rings….only when it’s growing
The size of the ring or amount of C13, neither can tell you climate or temperature….only the length of that periods growing season…..

Neville

Thanks very much for this Anthony and thanks to Pierre. Even I can understand this info and graph.
BTW have a look at these two charts of SLR showing all the models from Antarctica and Greenland, i.e. 99% of the planet’s ice. This is out to the year 2300.
http://rsta.royalsocietypublishing.org/content/364/1844/1709/F4.expansion.html
Greenland ( 10%) is positive for the next 300 years but Antarctica is negative. ( 89%) So where is all this dangerous SLR going to come from I wonder?
But why isn’t info like this used to counter the likes of alarmists Gore and Hansen, Flannery etc.

Roy

The subtitle of the article is Since when is Japan located in the North Atlantic?
Well, in the days of Apartheid the South African regime ensured that visiting Japanese people were treated as honorary whites. It would have been bad for business to do anything else. Similarly, for the purpose of saving the planet, the Japanese islands can be treated as North Atlantic islands. After all, we have got to get rid of the medieval warm period, haven’t we?

Merovign

Well, the MWP was obviously still a strictly local phenomenon. Just local to the North Atlantic, Antarctica, and Japan. Maybe Australia, and Russia. Also the Middle East, Africa. Possibly North and South America. And some oceans.

It’s local to Earth. Just local!

“Even less confidence can be placed in the original conclusions by Mann et al. (1999) that “the 1990s are likely the warmest decade, and 1998 the warmest year, in at least a millennium”…..”
–National Academy of Science report on the Mann Hockey Stick Graph, page 4
http://www.nap.edu/openbook.php?record_id=11676&page=4

Jimbo

They didn’t measure tree rings? If so then this is an outrage! Carbon-13 I tells ya!!!
Now onto some past related events. The MWP was a global phenomenon.
http://www.co2science.org/data/mwp/mwpp.php
(Lots of peer reviewed papers)
M. Mann’s Hockey Stick is a figment of his delusional imagination.

mfo

I think it’s reasonably well known that Sebastian Lüning & Fritz Vahrenholt have recently written a book which at present is available in German. I believe it reached number 1 (22,000 sold) on Amazon’s listing of books about ecology and the environment. It is called ‘Die kalte Sonne: Warum die Klimakatastrophe nicht stattfindet’ or ‘The Forgotten Sun: Why the Climate Catastrophe is not taking place’.
Hopefully it will become available in English.
http://www.amazon.co.uk/Die-kalte-Sonne-Klimakatastrophe-stattfindet/dp/3455502504
This is one of the interviews given by Fritz Vahrenholt about the book and his views on climate change together with another article which is a debate between Rob van Dorland and Bart Verheggen v Sebastian Lüning & Fritz Vahrenholt. Fritz Vahrenholt is an interesting and dialectical figure in Germany: The book has been criticized in German newspapers and a lecture he was due to give at the University of Osnabrück was cancelled because the subject of the book was considered too controversial.
http://www.europeanenergyreview.eu/site/pagina.php?id=3681
http://www.europeanenergyreview.eu/site/pagina.php?id_mailing=282&toegang=6a9aeddfc689c1d0e3b9ccc3ab651bc5&id=3740

Rick Lynch

I was confused by the statement that the Hockey stick chapter ended. I was under the impression that the IPCC and the “team” still believed in it.

Jimbo

All this unprecedented wamth rubbish leaves me cold.
http://wattsupwiththat.files.wordpress.com/2012/06/alley20001.gif

Jimbo

davidmhoffer says:
June 17, 2012 at 11:28 am
I was about to poo poo this as another tree ring study, but then I noticed they didn’t use tree ring width they used C13 to correlate to temperature. OK, suddenly the study has credibility in my eyes. But doesn’t this beg an additional question?
Would this technique not be valid for other tree ring studies?

I was just thinking the same thing? Come on Mann let’s give it a shot. Briffa? Heh, heh.

Greg House

By Sebastian Lüning & Fritz Vahrenholt: “…However, anyone who knew a little something about the scientific literature soon began to wonder. The Medieval Warm Period and the Little Ice Age as a local North Atlantic phenomenon? A nutty claim.”
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I am afraid it goes beyond that with nutty claims. Yes, the MWP and the LIA as a local phenomenon is a nutty claim, but at the same time the MWP and the LIA as a global phenomenon is a nutty claim, too. The same goes for the present “global warming”: a nutty claim. But maybe we have a global cooling instead? No, it would be a nutty claim. What about “neither cooling, nor warming” then? Sorry, a nutty claim again.
Why? Because the data available is not sufficient to draw any conclusion of the kind.

Jimbo

tonyb says:
June 17, 2012 at 1:56 pm
Bearing in mind that we pour scorn on Manns tree rings as being an unreliable proxy for temperature for a myriad of reasons (limited growing season, susceptibility to local micro climates etc) we shouldn’t rush in to praise this study just because it tells us what we want to hear.

tonyb, need I remind you we are in guerrilla warfare. Let Warmists find fault with C13 and post it here. Let them show how tree rings are a better proxy than C13. We are in a David V Goliath situation and David cannot afford to be Mr. Fair Guy. Warmists can afford to be Mr. Fair guy yet they are certainly not but they are still losing.

Peter Gulutzan

The article refers to “the South Pacific island of Yakushima”. But wikipedia says Yakushima is latitude 30 North. http://en.wikipedia.org/wiki/Yakushima
[REPLY: You are, of course, correct. Anthony’s original Google translation correctly referred to “…the southern Japanese island of Yakushima…” but Pierre Gosselin’s version, which replaced it, contains the error. Anthony has been notified. -REP]

polistra

Interesting curve! I’d be inclined to guess that the fast wiggles before the Völkerwanderungspessimum were an abnormal period requiring a catastrophic explanation, and everything after that is a return to a nice periodic pattern that doesn’t need any special handwaving.
Can’t have that, of course; the modern period has to be the abnormal catastrophic tipping-point, because only the modern period contains nasty sinful Western civilization.
Incidentally, Pessimum is a wonderful word. It’s the logical counterpart of Optimum, but for some reason it never formed in English.

clipe

mfo says:
June 17, 2012 at 4:10 pm
I think it’s reasonably well known that Sebastian Lüning & Fritz Vahrenholt have recently written a book which at present is available in German. I believe it reached number 1 (22,000 sold) on Amazon’s listing of books about ecology and the environment. It is called ‘Die kalte Sonne: Warum die Klimakatastrophe nicht stattfindet’ or ‘The Forgotten Sun: Why the Climate Catastrophe is not taking place’

http://wattsupwiththat.com/2012/02/06/germany-in-skeptical-turmoil-on-both-climate-and-windfarms/

Gail Combs

Thank you Pierre Gosselin, for bringing this to our attention and translating it.
Are there any papers analyzing the data from the Emperor’s gardens?

Gene

omnologos says:
> Have a look at the wiki entry for the Migration period for a laugh about the absurdist use of “global warming” http://en.wikipedia.org/wiki/Migration_Period
I find it curious that the English page on migration is the only one that looks stupid, out of half-a-dozen I checked. The Italian page, for example, fails to mention climate among the causes of migration; others do it in a tentative way: “Los hunos eran un pueblo nómada … que empezó a emigrar hacia el oeste en el siglo III, probablemente a causa de cambios climáticos.”
Comparing various national versions of Wikipedia pages is a source of endless fun; even though the pages are linked, their authors seem to be unaware of each other’s efforts.

Rattus Norvegicus

I’m just not sure that d13C has been well established as a T proxy. I was able to find some evidence that it served as a proxy for RH in a species of tamarisk in North Africa. Unless Rubisco has been shown to have a preference for d13C at either higher or lower temperatures I can’t see this relationship as holding.
The proportion of d13C in the atmosphere has no relation to T except for the changes which are attributable to burning of fossil fuels, so the action of Rubisco would be the mechanism. Anyone have any refs which might proved or disprove this point? I found one which might explain something but can’t read it until I am on campus tomorrow.

The other Phil

@Otter
I made a point of linking to this, as soon as I saw it at P. Gosselin’s page. Expect the usual drivel from stokes, connolley et al. They’re most lazyteenagers, after all.
Do you think this is a helpful way to advance the discussion?

Joe Prins

Thank you Pierre and Dr. Sebastian Lüning and Prof. Fritz Vahrenholt and Anthony. One sometimes wonder with all this CAGW drivel in the MSM, could i be wrong? After reading history for most of my life all of a sudden the MWP and the LIA disappears? Could all those starving Europeans during the LIA have been faking it? And it appeared in the Geophysical Research Letters in 1995? And the GRL never noticed? Where are the editors? Replaced by the Team?
But thank you so much. Faith in the fairness and honesty of scientists is slowly being restored.

davidmhoffer

Jimbo;
tonyb, need I remind you we are in guerrilla warfare. Let Warmists find fault with C13 and post it here>>>>
No need to stoop to their level, in fact doing so causes more harm than good because the warmists influence the MSM heavily, and any misstep by skeptics gets magnified as a result.
That said, I cannot completely agree with tonyb. He is absolutely correct that C13 cannot possibly measure temperatures during the non growing seasons. That said, for the growing season, the only influence on C13 (based on my reading on the matter anyway) is temperature. If the warmists insist on using trees as thermometers, it makes more sense to be critical of their methodology on both counts. First regarding the growing season and second that tree ring thickness is influenced by disease, pestilance, precipitation, cloud cover, foraging animals, late frosts and many other factors.
If we pursue a methodology that ACTUALLY measures temperatures that trees were exposed to during their growing season, and it confirms the tree ring growth, so be it. But I’d give rather long odds that it won’t.

Gunga Din

Rick Lynch says:
June 17, 2012 at 4:16 pm
I was confused by the statement that the Hockey stick chapter ended. I was under the impression that the IPCC and the “team” still believed in it.
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I’m sure I’ll corrected if I’ve got this wrong. Mann and “The Team” are the only ones who appear to be publicly defending it. IPCC no longer does … but they keep acting like it’s true. They’ve just found other equally “vaild” one-study-wonders to justify the actions they’ve always wanted to take.