Guest Post by Willis Eschenbach
The quote above is from Lord of the Rings, an exchange between Gollum and Smeagol, and it encapsulates my latest results from looking into the Shakun 2012 paper, “Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation” (paywalled, at Nature hereinafter Shakun2012). I discussed the paper in my post “Dr. Munchausen Explains Science By Proxy“. Please see that post for the underlying concepts and citations.
When I left off in that post of mine, I had investigated each of the 80 proxies used in Shakun2012. I plotted them all, and I compared them to the CO2 record used in their paper. I showed there was no way that the proxies could support the title of the paper. Figure 1 recaps that result, showing the difficulty of establishing whether CO2 leads or lags the warming.
Figure 1. All proxies (green dots) from Shakun2012 (Excel spreadsheet). CO2 values digitized from Shakun 2012 Figure 1a. There is pretty good agreement between the warming and the changes in CO2.
Note that the proxies say the earth generally warmed from the last ice age, starting somewhere about 15,000 BC, and the warming lasted until about 9,000 BC. Since then, the proxies have the greatest agreement (darkest green). They say that the globe generally cooled over the length of the Holocene, the current interglacial period since the last ice age.
Today I was thinking about that single record that they used for the CO2 changes. I got to wondering what other ice core CO2 records might show about the change in CO2. So I went and downloaded every ice core CO2 record that I could find that covered the time period 26,000 BC to modern times. I found a number of ice core records that cover the period.
Then I collated all of them in Excel, saved them as a CSV file, opened the file in R, and plotted every ice core CO2 record that covered the record from 26,000 BC up to the present. I standardized them over the same period covered by the Shakun2012 CO2 data. There was excellent agreement between the Shakun2012 data and the ice core records I had downloaded … but there was also a surprise.
Figure 2 shows the surprise …
Figure 2. As in Figure 1. Black circles show Shakun2012 CO2. Additional colored dots show the ice core CO2 records which have data from 26,000 BC to the present.
Dang, I didn’t expect that rise in CO2 that started about 6,000 BC. I do love climate science, it always surprises me … but the big surprise was not what the ice core records showed. It was what the Shakun2012 authors didn’t show.
I’m sure you can see just what those bad-boy scientists have done. Look how they have cut the modern end of the ice core CO2 record short, right at the time when CO2 started to rise again …
I leave the readers to consider the fact that for most of the Holocene, eight centuries millennia or so, half a dozen different ice core records say that CO2 levels were rising pretty fast by geological standards … and despite that, the temperatures have been dropping over the last eight millennia …
And I leave everyone to ponder how far climate “science” has fallen, that a tricksy study of this nature can be published in Nature, and can get touted around the world as being strong support for the AGW hypothesis. The only thing this study supports is the need for better peer review, and at a more basic level, better science education.
My best to all, stay skeptical,
w.
Source data:
ICE CORE CO2 DATA: All ice core CO2 data are from the NOAA Paleoclimatology site, the “Ice Core Gateway” page, in the section “Gases”.
[UPDATE] A hat tip to Jostein, in the comments he points out that the original Shakun Nature paper is here (pdf).
Nick Stokes says:
April 8, 2012 at 4:52 am
Nope. The “specific event” is the temperature change at the end of the ice age.Their graphs showed well beyond the period of the temperature rise at the end of the last ice age. In fact, the temperature rise was about 6,000 years long. They showed another 5,000 years past that, almost as long as the rise itself, and about half the length of the entire Holocene. So your argument, that they just showed what they were discussing, runs aground on an ugly reef of fact … they showed half the Holocene on their graph.
Finally, their claim is that the warming is “driven by increasing CO2 concentrations”. But the CO2 continues to increase, and the warming stops … which threatens their argument, as I said above.
You can continue to believe they extended the record for 5,000 years beyond the interglacial transition and that it was just an unlucky coincidence that they happened to stop showing the CO2 at the very instant it started to rise.
Me, I’ve dealt with too many victims of Noble Cause Corruption to believe in coincidences that unlikely.
w.
“The only thing this study supports is the need for better peer review, and at a more basic level, better science education.”
More red tape isn’t the answer for a system already red taped into a straight jacket. Rigid strength’s good for support, but flexibility’s essential for mobility. The problem is a lack of people qualified to supervise. Messing around with peer review’s patently NOT a substitute for NO ONE getting fundamentals right. Iterative adjustment of math education at a sustainable pace (it will take decades if not millennia) is the viable liberating option.
The other CO2 records also seem to show the start-of-the-Holocene rise in CO2 coming later than Vostok does. Does this obliterate their multi-proxy CO2-came-first claim?
Affizzyfist says:
April 8, 2012 at 5:45 am
I could write fifty comments to Nature. They will never withdraw the paper, and at least somewhat reasonably so. Journals generally only withdraw a paper if it can be shown to be actual fraud, not just incorrect claims.
In addition, I would argue strongly that what is written here has more impact than a “Comments Arising” in Nature.
w.
Lincoln Sparrow says:
April 8, 2012 at 7:44 am
Say what? As far as I know I did show all of the CO2 data and all the proxy data for the entire period 26,000 BC to the present … what am I missing?
w.
Chris V says:
April 8, 2012 at 7:29 am
Say what? I find no graphs in Shakun’s paper that shows anything more recent than about 6,500 years before the present. Which graphs are you talking about?
w.
Pamela Gray says:
April 8, 2012 at 8:59 am
“I tend to agree with Nick on his point that during the period under consideration, leading and lagging assumptions are questionable regarding the oft repeated notion that CO2 lags behind temperature increases.”
Okay, so what is the value of Shakun’s paper? I’m amazed that Nick Stokes and Pamela Gray, two whom I’ve come to respect here, would not be troubled by the the rest of the record. Shakun is attempting to show that the present day theory of CO2 rise causing temperature rise is also true of the end of the last ice age. This is the context in which you must understand the paper. Let us pretend that we didn’t know about the greenhouse effect of CO2 and Shakun was exploring this possibility. Let us assume that he was able to satisfy us that CO2 “slightly” (his words) preceeded temp in the record up to 6000 ybp. Surely looking at the rest of the data since 6000bp, Shakun would be disappointed that the relation didn’t appear to bear up. If this is okay for you guys and Dr. Shakun, then it would seem possible to present square orbits and P1V1=P2/V2 with constant T up to 6000ybp. Please, tell me you are troubled by the truncation of the data which appears to hide the real basic question being investigated by Shakun.
Well that didn’t take long did it? Shakun junk science completely debunked by Willis!
Even the usual trolls sound ridiculous in the defence of their cherished beliefs. For best hilarity, see Nick Stokes previous posts. Apparantly Shakun shows that CO2 rises preceded temperature rises. Ehrm, no they didn’t Nick. Taken individually, Willis has shown that the temperature proxies are all over the place – some follow the CO2 proxy, some precede it and some don’t have any direction when CO2 changes.
If a sceptic had produced such a study to show that CO2 lagged temperature, Stokes would have been all over it. The credibility of this man has just fallen lower than Nixon after Watergate. Shame to see an otherwise worthy opponent fall so low.
Hutch says:
April 8, 2012 at 7:59 am
I used BC and AD here as a deliberate choice, because I am writing for a mixed audience, and many folks are much more used to BC / AD than they are to years before 1950.
I used the timescale used by the original authors for each study. The Shakun2012 paper also includes (in some cases) alternative time calculations, either IntCal04 or 09. However, none of them change the results in any significant manner, as the differences in the timings of the proxy warmings are thousands and thousands of years, much more than the slight adjustments from different timelines.
w.
Chris V, you wrote, “The graphs from Shakun’s paper that are included with the abstract all show CO2 levels up to the present:”
No they don’t. Every single one of Shakun’s Nature Figures stop at 6500 years BP.
Volker Doorman: Science is to show agreements in nature, not to being skeptic on possible agreements, because skeptic is not a method of science.
This is backwards. Science is unique among the ways of knowing in its great respect for skepticism. Other approaches emphasize faith, but scientists accept as possible truths only those assertions that survive extensive skeptical challenges.
1. Mike’s Nature Trick Redux.
2. Proof that Man has been disturbing the atmosphere for 6,000 years. Or something has.
3. Intriguing: Younger Dryas shows up as sudden jump of CO2 about 12,000 YBP, ending about 10,300 YPB? With a DROP in temperature of about 1C, by eyeball of the green dots? Proof that higher CO2 causes temperatures to fall, by the cherry-picking method.
Actually, the Younger Dryas interval is an interesting part of their work.
4. And the research ASSISTANTS didn’t notice the more recent data has been left out?
There are going to be some interesting war stories from the younger set in a few years time.
Willis Eschenbach says:
April 8, 2012 at 10:31 am
Dave says:
April 8, 2012 at 3:34 am
“It has been my understanding that there is a difference in timing, to responses of climate change drivers, between the southern oceans and the northern oceans. Would this timing difference show and what would it be, if Willis replotted the proxies for both southern and northern oceans together with the proxy temperature record/s?”
I addressed this question in a comment to my previous post, “Dr. Munchausen Explains Science By Proxy”, here’s the graphic from that comment.
The unanswered question is: What power in Watts have and where are the terestrial climate change drivers?
If they would be on Earth, why then the terrestrial temperatures follow heliocentric (tide) functions?
http://www.volker-doormann.org/images/vo_m4k.gif
Riding on terrestrial climate drivers, means riding a death horse.
V.
Pat Frank says:
April 8, 2012 at 2:38 am
Shakun’s PhD thesis is here (3.7 MB pdf file). None of the figures in his thesis extend to times more recent than -6500 years ago.
Hey, the Earth and Universe are only 6,015 years old, right? %P
Willis, this is really good work, and I want to repeat my recommendation that you submit a letter to Nature.
About this of yours: I could write fifty comments to Nature. They will never withdraw the paper, and at least somewhat reasonably so. Journals generally only withdraw a paper if it can be shown to be actual fraud, not just incorrect claims.
In addition, I would argue strongly that what is written here has more impact than a “Comments Arising” in Nature.
Respectfully (I hope you believe this), I want to repeat my recommendation that you submit a letter to Nature. One way or another they will have to respond, and if they merely ignore you, you will be able to inform us of that fact, which some day could be another episode to be listed in the growing doubts that Nature is honest and rigorous in its treatment of climate science. It will add to the impact of your posts here, not be less or more, as you put it. Also, there are examples of papers being withdrawn for incorrect claims, not just for fraud. The Shakun paper was OK, except for one unsubstantiated claim that got blown out of proportion: the claim that they had shown that CO2 increase preceded global temperature increase. You showed before that their claim had no empirical support, once the full data were presented in a way to assess random variability. You showed today that any mechanistic interpretation of the unsubstantiated claim is contradicted when the full CO2 record is included with their temperature proxies. Shakun et al probably only included the truncated CO2 record because of their interest in the end of the particular ice age (or may claim so), so there is no need to assert any dishonesty, merely an unfortunate focus by them.
You have already done most of the work that a letter requires. Just put it all together, include all graphs that you have produced up til now, and keep the text succinct, omitting any hints of accusations. I don’t know about Nature, but Science will occasionally publish two really short notes together alerting readers to a critique and rejoinder that they can read about on line.
I bet that there was disagreement among the authors over the insertion of the unsubstantiated claims. I know of instances of that happening, especially in the transition of a PhD thesis to a submitted paper. In the academic world, publish or perish is the norm, and a young researcher may be forced to go along with claims he or she does not agree with. Mind you, I don’t know that happened in this case, but if you write your letter without any hint of exposing possible dishonesty, …, well, I think you have a better chance of a better outcome.
Chris V (April 8, 2012 at 7:29 am) wrote:
Am I missing something here? The graphs from Shakun’s paper that are included with the abstract all show CO2 levels up to the present.
Willis Eschenbach responded (April 8, 2012 at 10:55 am):
Say what? I find no graphs in Shakun’s paper that shows anything more recent than about 6,500 years before the present. Which graphs are you talking about?
My question: The graphs in the actual Shakun’s paper – behind paywall – apparently are different from the ones that Chris V refers to (coupled to the Abstract). Willis, can you please clarify this point because it is vital for your analysis!
Willis, this is good work. many thanks. You wrote: Finally, their claim is that the warming is “driven by increasing CO2 concentrations”. But the CO2 continues to increase, and the warming stops … which threatens their argument, as I said above.
I agree, and that is why I think you should submit this as a letter to Nature. You have made two good points: (a) claims that CO2 increase preceded temperature change are not supported in the data that they reported on in their paper; (b) claims that CO2 increased caused temperature increase are undermined by the complete CO2 records. You have already done most of the work for your letter. The letter will add to, the impact of these posts, not simply be less than or more than. If they don’t publish, you will alert all of us to that decision. In your letter, include all the graphs that have presented to us so far, but keep the text succinct and avoid hints of dishonesty. Mistakes like this can occur in many ways, too numerous to mention. This field has too many accusations of dishonesty already. In this case, it was probably a result of focusing too narrowly on one transition in the geological record. I would say that it is more important for the science that you get the full record published (your figure 2 today), than to ascertain how the mistake (as I call it) occurred.
Submitted with respect, if I may paraphrase Rod Serling.
This is an Easter treat.
Willis,
I don’t think that the Gollum Smeagul conversation was necesary and it may work adversely on a serious dismembering of this ‘study’.
Some thoughts. A study like this is not science per the Popperian phylosophy and Feynmanian ethics. See for clarification this thread.
http://www.physicsforums.com/showthread.php?t=589055
Next, the 6500 cal year BP limit is covered in the readme tab of the exel sheet:
“All ages are given in yr BP, where Present = 1950 AD. Age models were constructed with focus on the deglacial interval (22-6.5 ka). They should be used with caution outside of this time window (e.g., ages near core tops were not constrained to be greater than 0 yr BP).”
Furtermore, all temperature reproduction work is proxies. Inherently an unavoidable affirming the consequent fallacy. (If A then B, B hence A). An example of a catastrofical crash can be seen within this work!
There are several ways to reconstruct sea surface temperatures, the most reliable is thought to be TEX86 (googleable) and C37 alkenone. Huguet et al 2006 (in the study) tried both with disastrous results:
http://www.agu.org/pubs/crossref/2006/2005PA001215.shtml
These are in the study, tabs NIOP-905, while the graphs should be identical, this is the plot:
http://dl.dropbox.com/u/22026080/huguet-2006.png
There is no reason to assume that other proxies are any better, including the isotopes in the ice cores. But this is the kind of evidence that should support the notion about temperature resonstructions.
Clams got feelings! Oceans, too.
Got data for that?
😉
While a lot of this stuff makes my eyes glaze over, this finding seems pretty simple, clear and possibly extrordinary.
Beyond killing this paper, it also kills the whole AGW hypothesis – 8000 yrs of generally increasing CO2 & associated general decline in temps. 180 deg out of phase with the hpothesis – how much more data do we need anyway?? Come on now! Put a fork in AGW! It’s done!
Eric Adler says:
April 8, 2012 at 9:53 am
“Willis Eshenbach…
“Your comment has no bearing on the validity of the paper you are trying so hard to impugn.”
As his ^comment^ makes clear, Eric Adler has zero understanding of the scientific method. It is the duty of scientific skeptics to tear down conjectures whenever they can. Willis has done an excellent job of deconstructing Shakun et al.
Shakun is just pulling a Michael Mann trick, using carefully cherry-picked proxies to arrive at a conclusion at odds with the mountain of evidence showing that a rising temperature results in rising CO2, just like a warming Coke outgases CO2.
Much as I wish it was, it isn’t (a word). “obfuscation” is prob’ly what you intended.
😉
😀
Mr. Eschenbach’s rebuttal of the Shakun paper is a disgrace to science. The new scientific method is to look only at data that supports your theory. Other data is irrelevant. I’m sure he knows this but mischievously follows the older outdated and antiquated scientific method. <—– humor