McIntyre finds the Marcott 'trick' – How long before Science has to retract Marcott et al?

Steve McIntyre has made what I can only describe as a stunning discovery as to why there is a sharp uptick in the main Marcott et al graph being touted by the media from its publication in Science.


It seems the uptick in the 20th century is not real, being nothing more than an artifact of shoddy procedures where the dates on the proxy samples were changed for some strange reason.

McIntyre writes:

The Marcott-Shakun Dating Service

Marcott, Shakun, Clark and Mix did not use the published dates for ocean cores, instead substituting their own dates. The validity of Marcott-Shakun re-dating will be discussed below, but first, to show that the re-dating “matters” (TM-climate science), here is a graph showing reconstructions using alkenones (31 of 73 proxies) in Marcott style, comparing the results with published dates (red) to results with Marcott-Shakun dates (black). As you see, there is a persistent decline in the alkenone reconstruction in the 20th century using published dates, but a 20th century increase using Marcott-Shakun dates. (It is taking all my will power not to make an obvious comment at this point.)

alkenone-comparisonFigure 1. Reconstructions from alkenone proxies in Marcott style. Red- using published dates; black- using Marcott-Shakun dates.

In a follow-up post, I’ll examine the validity of Marcott-Shakun redating. If the relevant specialists had been aware of or consulted on the Marcott-Shakun redating, I’m sure that they would have contested it.

Read his entire post here.

This is going to get very interesting very fast.


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Yet another example of torture not yielding correct results.
Even the statisicians at the Tobacco Institue could do better.


Does Steve feel this was a pure mistake or something more sinister….lies?

Alex the skeptic

Tick, tick, tick- how long will the new Marcott et al hockey stick survive?
That was yesterday’s question. Now the answer is here. Marcott’s hockey stick has been murdered by the truth.


Here is another case where someone who is a real statistician with a real understanding of these analytical methods finds defects or insufficiencies.
From the look of the graphs and the vagaries of both lines in the modern era I have to wonder whether the alkenone proxy is at even usable to estimate temperature.

Robert of Ottawa

There are two successful ways to commit fraud, either do it in plain sight so no one will believe it could possibly be so (Madoff); or hide it under layers of subtefuge (Marcott et al.).
Really, this takes the biscuit.


GlynnMhor says:
March 16, 2013 at 3:56 pm
“From the look of the graphs and the vagaries of both lines in the modern era I have to wonder whether the alkenone proxy is at even usable to estimate temperature.”
Well obviously one proxy is not enough to estimate global temperature. Had they cut off their result before the proxy dropoffs the result would have been defensible.
They couldn’t resist to add a “non-robust” Hockey Stick; temptations of a warmist post doc, what a boring life they must have (had).

cui bono

7 stages of reaction to the death of yet another Hockey Stick:-
1. SHOCK & DENIAL- No, they couldn’t have done that – could they?
2. PAIN & GUILT- How could I allow my taxes to be spent on this rubbish? Maybe it’s my fault?
3. ANGER & BARGAINING- Perhaps this team could be redeployed into auto repairs.
4. “DEPRESSION”, REFLECTION, LONELINESS- Real science is dying out. Sigh. Sob.
5. THE UPWARD TURN- Wheeee! Another one bites the dust!
6. RECONSTRUCTION & WORKING THROUGH- So what were the real temperatures?
7. ACCEPTANCE & HOPE- Maybe they’ll get the message – ‘don’t mess with McIntyre’!

Hoo-boy. And just in time for the next AR, too.


Suddenly a heated discussion took place between a client and the management of the Marcott-Shakun dating service….”but the online profile said it was a HUGE up-tick!”

Leonard Lane

Good work, these frauds, deceptions, data corruptions, and “mistakes” must be pointed out and documented in the literature so that one crook after another may not build on the original fraud or “mistake”. If the “mistakes” and hockey sticks went down in the last few decades as often as they went up then you could write them off to ignorance, incompetence, sloppy work, or mistakes. But when all the “mistakes”, frauds, errors, etc. always increase the temperature in the last few decades then you there is a high probability that all upward pointing hockey sticks are frauds.

In Years (BP) time zero is 1950 in Marcott.
Marcott shows a spike in 1940.
In the McIntyre Fig. 1, the red curve appears to go to 1980 or 1990. A couple decades later than Marcott.
Awe, heck. Why didn’t Marcott use a scalpel every 500 years and just do a bet fit on the segment slopes? (Just Kidding!)

John Kenny

Maybe, just maybe this will be the moment when the world realises what is happening, not just us sceptics, and the uncritical acceptance of ‘the science’ will never be the same again.
Here’s to you McIntyre!


“It is taking all my will power not to make an obvious comment at this point.”
Hide the decline!

Andy Wilkins

I’m afraid I’m going to have to say it out loud:
They deliberately messed with the figures to fit a pre-conceived agenda.
It’s depressing to see science abused in such a way. Thankfully we have Steve M to bring some sanity to the chaos.

Robert of Ottawa

Cui Bono,
Repeat hockey stick and avoid steps 1 to 7.


cui bono says:
March 16, 2013 at 4:12 pm
“3. ANGER & BARGAINING- Perhaps this team could be redeployed into auto repairs.”
Are you mad?

Gary Hladik

Alex the skeptic says (March 16, 2013 at 3:50 pm): “Marcott’s hockey stick has been murdered by the truth.”
Mr. McIntyre, at Climate Audit, with a magnifying glass.

David, UK

To the words of Mull of Kintyre:
Steve McIntyre
Old tricks are no contest to him
His desire
For justice will lead him
Oh Steve McIntyre



Why will it get interesting, why would Science(tm) care? At best, someone might get a politely worded note, if the math is obscure enough, on their web site.

Werner Brozek

The final date of the Marcott reconstruction is AD1940 (BP10).
Could part of the problem be that they are confusing themselves and others with an archaic way of saying which year they are really talking about? If BP means before 1950, what would 2013 be? It would almost be as if an old article was written using the Rankine scale and a modern article refused to convert to C for newer readers. A high positive number on the Rankine scale, such as 200 R would be a large negative number on the scale in degrees C.


Ever the gentlemen you two are, describing this as “nothing more than an artifact of shoddy procedures where the dates on the proxy samples were changed for some strange reason”.
Marcott shifted 2 cores (with negative values) so that they occured just barely outside the closing period, and shifted 3 cores (with positive values) of years 1000, 690 and 510 years later than their published dates to “0 BP”.
I will say it – this is straight-up academic malfeasence. And just in time for AR5. By a Mann wannabe ?

David, UK

To the TUNE, even.

I’d say it’s a “sign” problem, but that doesn’t explain the pre-1900 data.


This just seems surreal. They could have just made up the data, it would have taken longer to debunk that way. I hate to be a proponent of conspiracy theories, but it just seems like Marcott is the sacrificial lamb to distract attention from something else. CG3?

Ian W

It seems the uptick in the 20th century is not real, being nothing more than an artifact of shoddy procedures where the dates on the proxy samples were changed for some strange reason.
One wonders how many times these ‘shoddy procedures’ were iterated until for ‘some strange reason’ a hockey stick was obtained.

Iggy Slanter

Why is this surprising? To quote the old movie “you just don’t get it, do you? It’s what he does!”
Juicing the numbers to heat the planet is the norm for these guys, along with a lot of other stuff that we are all aware.
It’s not a bug, it’s a feature.


Tick, tick, tic, – a commenter yesterday thought 6 weeks, I almost replied less than 2. Whatever the time, this piece of sh!t has to be flushed soon. Even the Guardian and BBC have avoided their usual OTT reporting. BBC none this morning, Guardian 1 an AP feed.


By the way, where are the usual Warmists on WUWT defending this paper???


I would not want to be in Marcott’s shoes. There is no doubt he has not had a good night’s sleep over the last 4 days. You can res assured he has been frantically communicating with his PHD mentors and Michael Trickster Mann. All to no avail. Marcott withdraw your paper by yourself before it is forced upon you. Don’t listen to your ‘advisors’ they are using you as a usefull idiot.

Noblesse Oblige

Anthony, it’s worse than this. Evidently Marcott’s thesis did not have the uptick , so something happened afterward whereby it got in. It is more than possible that it got inserted in the Science review process by hockey stick advocates, which then greased the skids for its publication.
The victim in all this, besides all of us who have been scammed once again, is Marcott who was just trying to get a PhD. And once again Science magazine has reasserted its status as supermarket tabloid of science.


Alex, The hockey stick is the living dead. It doesn’t matter how many times McIntyre kills it. Nothing can kill this zombie


But will MSM, or indeed anyone else, publish any of this?


Let us remind ourselves about some of the NH heat of the Holocene pre-20th century. It is unprecedented and worse than we thought.

We therefore conclude that for a priod in the Early Holocene, probably for a millenium or more, the Arctic Ocean was free of sea ice at least for shorter periods in the summer. This may serve as an analogue to the predicted “greenhouse situation” expected to appear within our century.
Arctic sea ice cover was strongly reduced during most of the early Holocene and there appear to have been periods of ice free summers in the central Arctic Ocean. This has important consequences for our understanding of the recent trend of declining sea ice, and calls for further research on causal links between Arctic climate and sea ice.
Calcareous nannofossils from approximately the past 7000 yr of the Holocene and from oxygen isotope stage 5 are present at 39 analyzed sites in the central Arctic Ocean. This indicates partly ice-free conditions during at least some summers. The depth of Holocene sediments in the Nansen basin is about 20 cm, or more where influenced by turbidites.
A 10,000-Year Record of Arctic Ocean Sea-Ice Variability—View from the Beach
We present a sea-ice record from northern Greenland covering the past 10,000 years. Multiyear sea ice reached a minimum between ~8500 and 6000 years ago, when the limit of year-round sea ice at the coast of Greenland was located ~1000 kilometers to the north of its present position. The subsequent increase in multiyear sea ice culminated during the past 2500 years and is linked to an increase in ice export from the western Arctic and higher variability of ice-drift routes
…Today’s ice cover (2 to 4 meters thick) over the Arctic Ocean provides a shadow that prevents coccolithophorids (photosynthetic, planktonic algae) from living there. Sparse, low-diversity, but indigenous coccolith assemblages in late Pliocene to mid-Pleistocene (but not Holocene) sediments imply deep penetrating warm currents or an ice-free Arctic Ocean, or both, as those layers were being deposited.

Rapid response of treeline vegetation and lakes to past climate warming
……………….Here we present palaeoecological evidence for changes in terrestrial vegetation and lake characteristics during an episode of climate warming that occurred between 5,000 and 4,000 years ago at the boreal treeline in central Canada. The initial transformation — from tundra to forest-tundra on land, which coincided with increases in lake productivity, pH and ratio of inflow to evaporation — took only 150 years, which is roughly equivalent to the time period often used in modelling the response of boreal forests to climate warming5,6. The timing of the treeline advance did not coincide with the maximum in high-latitude summer insolation predicted by Milankovitch theory7,…………………

……Tree birches (Betula pubescens Ehrh., B. pendula Roth.) reached the present-day shoreline of Barents Sea in Bolshezemelskaya tundra and 72°N in Taimyr between 8000 and 9000 BP……

Alan Clark, paid shill for Big Oil

Ohhh. That’s sure to get Steve another of those big cheques from Big Oil that wee-Mann is always yammering about. sarc/
It’ll surely get him a donation from me (which is actually money from big oil that I got fair and square).


It is as if provenance had brought us McIntyre and FOIA. And of course Watts et. al. As they say the truth will out. You just have to be patient.


Anthony, it is worse than this. Evidently the uptick is nowhere to be found in Marcott’s thesis.
So it is more than possible that somewhere in the review process, the uptick was added on, which greased the skids for its publication in Science. There is definitely something we don’t know here, but we do know that Science has reaffirmed its status as supermarket tabloid of climate science.


History repeats:
1. Amazing new peer reviewed paper published supports CAGW!
2. Media headlines. “it’s worse than we thought!”
3. Paper swiftly debunked
4. Er…
5. That’s it.


Shakun bake? (as in cooking the books….)

Peter Miller

Even Mann would be proud of making this big a Hide the Decline.

Clay Marley

OK so I read the post but I’m not seeing where the hockey stick comes from. As I understand it, Marcott re-dated the core sample proxy data. Since these proxy datasets were created over a 10 year time span, I can see taking the original raw data and re-calibrating the carbon dating for all the proxy sets to the latest standard (using CALIB 6). It would remove one source of variability. Was that the purpose of the re-dating?
But seems to me this would shift the data points to the left or right in time but not affect the temperature. So how does re-dating turn the red curve into the black curve?


This actually gives me a glimmer of hope. That they have to resort to such (apparent) fakery, that The Usual Suspects were going ball$ to the wall with this so quickly, shows desperation. Then again, a wounded bear cornered in a cave is desperate, but still dangerous. Anthony, Steve, many thanks.


Living in Oregon one likes to see Oregon people contribute to science and understanding of the earth. After reading the incompetence or fraud that this Marcott paper represents makes me very glad that my engineering degree is not from Oregon State. Last year Oregon State did not renew the contract of an assistant professor apparently because he didn’t agree with AGW, Now lets see how the university deals with incompetence and or fraud. Harshly if they want to maintain a semblance of integrity.

At Bishop Hill there’s a discussion of whether this is fraud or not. My comment:
Its got to rise to the level of fraud or something like that to get the attention of the lib MSM. The thing is that the story of the incontrovertible evidence of unprecedented modern global warming ran night and day it seemed for weeks. That’s all the people are going to know. Insane.


The real issue is not that Marcott and company fuzzed their data and shifted their dates.
The real issue is that none of Science’s putative reviewers spotted it and insisted they defend their rather interesting methods.
They may, in fact, have a defense for what they did. My guess, though, is that it’s worse than, say, using Graybill’s stripbark trees as a temperature proxy.


I guess this is another nail in the coffin of Dr Mann’s reputation ( is there any room left in the coffin for more nails ?!?! ) as he was one of the first to trumpet / tweet the great significance of the Marcott paper.

Reed Coray

In the movie Hoosiers when the Hickory Huskers were getting trounced early in the championship game, one of the Husker players during a time out said: “This Is Embarrassing.” IMHO the phrase “This Is Embarrassing” should be the official motto of Team cAGW.


And once again, it won’t matter. The number of people who will find out about this is miniscule compared to those that heard it’s all worse than we thought and we’re all doooomed. That’s how this game is played, science by press release to get media hype and when disproven later that doesn’t get reported.

“It is taking all my will power not to make an obvious comment at this point.” Bloody lying, liars, lied.


Statistics must never have been a prerequisite for gaining the (dubious) title of “Climate Scientist”. Spending a few years working for crooked casinos probably was, however, cooking the dice, rigging the tables, marking the cards, fudging the slots, and busting the kneecaps of anybody willing to expose these shenanigans. All in a day’s work, of course. You could never accuse “Climate Scientists” of Walking Tall–they’re the guys on the wrong side of that story.


I think all reputable scientific journals should require every step of data analysis, including data and code used for said analysis, be made available by the authors prior to publication. Perhaps on the journal’s website.