Marcott's hockey stick uptick mystery – it didn't used to be there

At Climate Audit, Something odd has been discovered about the provenance of the work associate with the Marcott et al paper. It seems that the sharp uptick wasn’t in the thesis paper Marcott defended for his PhD, but is in the paper submitted to Science.

Steve McIntyre writes:

Reader ^ drew our attention to Marcott’s thesis (see chapter 4 here. Marcott’s thesis has a series of diagrams in an identical style as the Science article. The proxy datasets are identical.

However, as Jean S alertly observed, the diagrams in the thesis lack the closing uptick of the Science. Other aspects of the modern period also differ dramatically.

Here is Figure 1C of the Science article.

figure 1C

Now here is the corresponding diagram from the (Marcott) thesis:


The differences will be evident to readers. In addition to the difference in closing uptick, important reconstruction versions were at negative values in the closing portion of the thesis graphic, while they were at positive values in the closing portion of the Science graphic.

I wonder what accounts for the difference.

Read the full report at Climate Audit


This story just got  a lot more interesting. I wonder if we don’t have a situation like with Yamal, and sample YAD06 which when included, skewed the whole set. Perhaps there was some screening in the thesis and that didn’t include part of the proxy datasets, or later for the Science paper maybe there was some Gergis sytyle screening that made hockey sticks pop out. It might also be some strange artifact of processing, perhaps some Mannian style math was introduced. Who knows at this point? All we know is that one paper is not like the other, and one produces a hockey stick and the other does not.

Some additional detective work is sorely needed to determine why this discrepancy exists and if anyone in the peer review process asked any similar questions.


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An even more intriguing possibility – perhaps the reviewers demanded Marcott add the hockey stick, as a requirement for their approval.
Marcott obviously knew the hockey stick was bogus – otherwise he would have added it to his PHD thesis paper.

Ben D.
Jimmy Haigh

It’s “climate science”. Innit?

Mike Bromley the Canucklehead in Cowburg

“if anyone in the peer review process asked any similar questions”
and if they did, were they bypassed, silenced, or censured?

Lance Wallace

Just this minute finished plotting all 73 of the Marcott proxies in the Science article.
The huge uptick is nowhere to be seen. There is a small increase that appears to be a continuation of the warming from the LIA. (Note that 0 on the graph is 1950 AD).


It is upside down and backwards


Almost enough to make me paranoid that someone really stupid is running the show. How else do you explain such central disorganization?

Anthony says, “Some additional detective work is sorely needed to determine why this discrepancy exists and if anyone in the peer review process asked any similar questions.”
Of course, this is true, but let’s please not ever lose sight of the fact that no ‘detective work’ should EVER be needed to understand how a peer-reviewed paper arrived at its conclusions. Of course there is no choice but to do that detective work – I understand the times and I get that completely. But ridicule is the only proper response to any so-called ‘scientist’ who refuses to show his work. Are you serious? You won’t show the public how you arrived at your conclusions? Seriously?
Why should that ever be taken seriously, in any way? “Hi, teacher. Here are the answers to the 10 homework questions. Of course I only put the answers, not my work, but you’ll give me a 100 anyway, right?” Any of you ever have a math class like that?
Between climateaudit and this site and the whole crowd-sourcing thing, eventually we will get to the bottom of the details of this fraud, just like all the others before and yet to come. But don’t stoop so low as to take this crap seriously – if they won’t show their work, they’re jokes, plain and simple. Yes, the detective work has to be done, as Anthony says – that’s the sad state of our times – and by all means do your worst to expose the fraud. But don’t ever lose sight of how utterly transparent and laughable these people are. Laugh at them. If you have a 2nd-grade education and can’t sign your own name, you’re miles above them. At least you’d have the stones to show your own work, wouldn’t you?

richard verney

Given the admission that the uptick is based upon data that may be considered to be “not robust”, I am not surprised to see that part of the data not included in the PhD thesis.


Could the different X axes of the two graphs be labelled clearly please? I guess the top one is years before present and the bottom one is just year number, but that is an assumption based on why they are reversed.

Lance Wallace

Here is Marcott’s Figure 4.2 from his thesis:
And here is the graph I prepared from his Science article, on approximately the same y-axis range.
Both graphs show a general decline of about 1 degree C from the early Holocene to a couple of hundred years ago, perhaps close to the Little Ice Age and a recovery on the order of 0.2 C until about 1900 and perhaps another 0.1 C to 1950, although the number of proxies by that time is more like 2 or 3 than 73.
The uptick in the Science article is certainly not from the 73 proxies themselves, which have very poor (300-year?) resolution. Instead, Marcott seems to have forced some kind of 20-year resolution in just a few of the latest proxies and done a whale of a lot of Monte Carlo sampling to make the blade of the hockey stick. Actually I have no idea how he/they did it. But from his response to Steve M.(“not robust”) he appears to be stepping back from the brink.

Robert A. Taylor

see chapter 4 here

63.1 MB PDF file; allow for time to download.

Read the full report at Climate Audit

Link is broken. At this time it is the top entry at


Link is broken.
Also – I refreshed CA 20 times yesterday and this appears as soon as I go to sleep?


I wonder who referred the paper? Perhaps the referees demanded that a hockey stick should appear.


[spelling mistake corrected]
I wonder who refereed the paper? Perhaps the referees demanded that a hockey stick should appear.

Lance Wallace

I spent an hour or so translating 73 separate Excel sheets from Marcott’s Supplemental Excel file into a single Excel file with age, temperature and a few other variables. Much easier to graph all data that way. For persons who know about fitting lines to noisy data (I don’t, other than making a running average), this file should be useful.

Peter Miller

In real climate science, the problem with hockey sticks is they are not there.
But no hockey stick = no funding = have to get a real job.
Hence, in today’s ‘climate science’ the hockey sticks are there.
The climate audit article is truly damning, but it’s ‘climate science’, so no one should be surprised.

New Recipie:
Marcott II Now with added FEAR- (Graph) Fiddling, Economy (with Truth) and Recycling (Mannian Maths)

Reblogged this on Climate Ponderings.


Good thing he is not a banker here in the UK. Wouldn’t last five minutes submitting contradictory graphs like that. /sarc


Bare in mind that these two had different functions , where has the ,Thesis had to be scientifically valid , with the author expecting a hard time in a viva.
The ‘research’ had to be politically useful for ‘the cause ‘ in order to get it into AR5 and to ensure the authors ‘Team ‘ place which still opens the door to much funding and career progression.
With the author aware that with the ‘right reviewers ‘ their work would have a much easer time in review.
The stick is where the majority of the political ‘value ‘ , and all that can bring , comes from .
So its not the actual research that matters but ‘what’ the research is needed for . And in that Marcott is merely following the ‘leaders ‘ in this field such has Mann .


Incredible… Are you sure Science is about… science? And that those authors/reviewers are scientists?


Shaun, dude, you’re royally screwed:


Ultimately it doesn’t matter in the “real” world. They’ve accomplished their goal, generating scary headlines in all the usual suspect media outlets. The Warmistas know how to play this game very well, it matters not whether or not it’s right, or if someone else later discredits it, that will never get any significant air time in the media. The goal is to produce AGW confirming headlines that allow politicians the support they need to instigate a carbon tax, with the emphasis on tax, which is what the whole game is about. Post normal science indeed. That and ensure more funding for said “scientists.”


“Page not found” error if you try to follow the link.
I wonder why?


You might like this from the other thread posted by the commenter BruceC.

suyts space
Hockey Stick Found In Marcott Data!!!!
Here’s the graph I wanted shown. This is from Hank’s work……
There is a hockey stick in their data!!! It just goes the other way! This is post 1950. So what did Marcott et al do? They erased this data and the splice some stupidity in it’s place. In the graph above, I on top of circling in red the real hockey stick, I also drew some green lines. This has been touched on the in comments of Hank‘s last post, but I’d like to reinforce this. Now, this is interesting all by itself………..
For people who may think I’m over the top by calling the stooges of team Marcott dishonest, I lose all sense of propriety when people lie to me and the public. And this is exactly what these knotheads did.


Hockey Schtick 2
If this is right then the IPCC and Science should be informed immediately.

Gras Albert

The climate Audit link says “page not found”. Remove the extra: http://
[Reply: Fixed. Thanks. -ModE]


Grammatical error:
… it didn’t use_ to be there. Not used. 🙂


In the second set of graphics (simulation diagram) at Climate Audit we see a sharp rise for ScienceMag and a decline for the thesis. Are they trying to hide the decline??? Did they consult Dr. Michael Mann before and during the write-up of the paper???

Louis Hooffstetter

Steve McIntyre says: “I wonder what accounts for the difference.”
The authors concluded “Our global temperature reconstruction for the past 1500 years is indistinguishable within uncertainty from the Mann et al. (2) reconstruction.”
It’s interesting (and career ending) that they would both emulate Mann’s completely debunked hockey stick with their diagram and then mention him in their article. I suspect the ‘David Blaine of climate science’, Dr. Michael Mann himself, had a hand in processing the data for the ‘Science’ article. But in exchange for what?

Lewis P Buckingham

Its almost as if the x axis has been turned around from 2000 to 0 then from 0 to 2000.Or better expressed the science article reverses the scale.
For some reason the Standard 30×30 grid has been almost mirror inverted as has green Standard NH.
There appears to be four proxies of temperature in the thesis and six in the science article.
Just by eyeball, if you add the error bars those lines could go anywhere on the graphs.
It would be useful to see what and which standards are being alluded to.


We have seen so many data alterations, to follow theory/model output, that this seems par for climate science, or should I call it pseudoscience. They still expect us to believe this rubbish as well.


As far as I can see there seems to be a rather dramatic increase in temperatures over the last 300 years in both sets of data. What’s that all about then? Clearly not AGW.

Geoff Withnell

My immediate thought is that the thesis committee did some actual review of the paper, while Science did not.

Ed Zuiderwijk

Another piece of Manniacal analysis?


Is it polite to ask whether Marcott’s defended PHD should be withdrawn or his recent paper should be withdrawn? Or re-written?


It would be interesting to know if the “not robust” uptick was in the original Marcott submission to Sciencemag, or did a reviewer (Mannian) press them for it….. or did the review process press for more “simulations” of a certain kind to exaggerate the uptick?? We may not be able to find out with confidentiality of reviews etc., but it’s a good question to have in mind as we explore how Marcott got from the diagram in the thesis to the one in the article.


I propose at first glance, that this may well be the result of tampering with results by “expert reviewers” demanding certain adjustments in order for the paper to be accepted.


As I predicted on another posting yesterday this paper will definitely be withdrawn and it will be end of the team.

Does anyone know who was on the peer review process? It is evident by both the volume of criticisms of the Marcott paper, and the timing of when they first followed its publication, that whomever they are, are not very good.


Oh noes! The Central England Temperature (CET) dataset has been made into a…………….. HOCKEY STICK! Even though it has been declining at a -4.4° C/century rate over the last 15 years. Climate trickery and general Tom foolery is our Marcott.
(Click then scroll down to see how the trick is done.)

Kelvin Vaughan

I downloaded the Central England Temperature since 1878 and sliced it up to coincide with each sunspot cycle. I then dived each years sunspot number by 32850. I subtracted the result from the yearly temperature. I then averaged the temperature over each sunspot cycle.
I plotted the temperature of the CET data and the averaged data. The CET data climbs slowly over the years then there is a hockey stick starting about 1996 where it climbs 2°C and looks like it is going to continue exponentially.
The adjusted data is virtually flat from 1890 to 1996 then rises 1°C before falling back a bit.
(You may be wondering why I divided the yearly sunspot number by 32850. I found out that that was the number that gave the flattest temperature over the CET data series since 1878.)


Louis Hooffstetter says:
March 15, 2013 at 2:52 am ” …I suspect the ‘David Blaine of climate science’, Dr. Michael Mann himself….”
Uri Geller of climate science, surely.


There seems to be more recent data in the top figure than the bottom (thesis) figure. Look at the lower edge of the grey uncertainty curve – there is a bump in the curve around 8 axis tick marks to the left of the 0 mark on the top figure, but on the bottom figure this same bump is only around 6 tick marks to the left. Of course the bottom x-axis is not labelled, so it’s hard to figure out how to align the two figures.

Bill Illis

Thanks to Lance Wallace at March 15, 2013, 1:24 am for collating the data,
We can now see where the hockey stick blade uptick comes from. There are a number of proxies with high numbers in 1950 (which then decline afterward). Otherwise, the average over recent period is below the average 0.0C anomaly and there is no trend overall.
But if you are running some type of filter up to just 1950 and then preserve the end-point, viola you have an uptick. Standard filtering problem.
Marcott’s proxies from 1700 to 2000 (and if you go back to 1400 or 1000AD, it looks exactly the same).

John Tillman

The Greenland ice core proxy data show that temperature (at least there) has been on a downtrend since the so-called Minoan Warm Period about 3300 years ago, & that the earth was even warmer during the Holocene Optimum. This trend is confirmed globally by other data sets, including the fact that the East Antarctic Ice Sheet stopped retreating about 3000 years ago, as shown by soil radionuclides. This down trend has been produced without major human contribution, except possibly from such activities as cutting forests & planting rice paddies, which to some extent merely replace natural swamps.
Thus a scientifically valid means of measuring the actual human contribution to global warming, if any, might exist. Draw a trend line connecting the tops of the observed temperature peaks during warm spikes (Minoan, Roman & Medieval), then extend it into the current Modern Period. If at some time in the present period (which still has 100-350 years to run) temperature peaks above the downtrend line would indicate by how much people have altered the natural course toward the next glaciation.

Reblogged this on This Got My Attention and commented:
Problems with the data, again, so just make up some?