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).
Hide The Increase!
I am reminded of the line… ” You can’t handle the Truth… “
Hide The Incline!
eight “centuries”? or millennia (occurs twice)
Eight centuries or eight millenia?
Note how the Younger Dryas shows up clearly in the temperature proxies but merely causes CO2 levels to flatten. Thats persuasive that rising temperatures cause rising CO2 levels. When temperatures fell during the YD, CO2 just stopped rising.
Otherwise, climate science is riddled with these kinds of deceptions. If you followed the Larsen iceshelf thread yesterday. I tracked down the source of the ‘2.5C warming over the Antarctic Peninsula’ claim and showed it would have almost no effect on temperatures over 0C and therefore almost no effect on iceshelf melt from atmospheric temperatures. Contrary to the repeated claim it is the cause.
“Jeremy’s Nature trick?” What can one say? Brilliant, thanks Willis.
Also its interesting to see the x-axis time variability in the CO2 rise as well as in the temperature rise(s). The CO2 proxy variability was also excluded from Shakun et al.’s “analysis”.
did you mean to write 80 centuries, or am I reading that graph wrong?
At last! A hockey stick! But hang on – its the wrong way round. No problem – we have some Finnish friends who can help out here…
Willis, brilliant as ever. Do you think Nature will accept a comment paper? (no sarc intended). If not there, this should be published somewhere.
Now the question is whether there’s Clark-group OSU ftp server with a CO2 data folder called, ‘up to 2000 CENSORED.’
Philip Bradley says:
April 7, 2012 at 11:14 pm
Note how the Younger Dryas shows up clearly in the temperature proxies but merely causes CO2 levels to flatten. Thats persuasive that rising temperatures cause rising CO2 levels. When temperatures fell during the YD, CO2 just stopped rising.
This is the point I made in the last thread – the presence of the Younger Dryas makes the initiation of the present interglacial fair game for this kind of AGW trickery, since – as you point out, temperatures rose twice, while CO2 rose only once. The resultant smearing in the time direction of temperature proxies (assisted by the huge variability and error in such proxies) allows Skakun et al. to get away with this conjuring trick. Its enough to allow the MSM e.g. BBC to crow that this powerful skeptical argument – temp rise predating CO2 rise – has been falsified, when it clearly has not.
It is curious how CO2 flatlined during the Younger Dryas.
Is Nature aware of this?
See “Dishonest, Delusional and Dangerous” – Piers Corbyn dismembers the latest Nature magazine claim propagated by BBC that CO2 drives climate.
http://www.weatheraction.com/docs/WANews12No20.pdf
This NEEDS to be published in the scientific literature.
Up, Up and Away…!!!!!!!!!
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 centuries …
That discovery deserves to be published. As well, the Sakun paper deserves to be thoroughly and publicly trashed. But I somehow doubt either will occur.
Thanks Willis for de-constructing another example of how not to do science.
This means that Shakun et al have shot themselves in each foot and now haven’t a leg to stand on! Will be interesting to see how Nature deal with the retraction.
Can someone do a graph of Northern hemisphere temperature AND NORTHERN hemisphere CO2?
Thanks
JK
Their title is
“Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation”
Seems clear to me. And that’s what they plotted.
Willis would you please make these proxy CO2 data avaliable for us?
I also notice that of the available CO2 records, the one they use shows the earliest rise. That counts as a half-tricksy, at least!
Nick Stokes says:
April 8, 2012 at 12:06 am
Yes, indeedy, and the fact that their proxy temperature data goes up as far as 1980, but their CO2 data ends just exactly when the CO2 starts rising again?
Coincidence. Pure coincidence.
w.
CO2 Gate
If Nature publish a retraction I wonder if the BBC will have the good manners to do the same – they were very quick (predictably) to trumpet the original story as it suited their pro-CAGW narrative very nicely: http://www.bbc.co.uk/news/science-environment-17611404
CO2gate
I only scored 27 out of 50. Probably would have scored more if I knew Greek.
It is quite simple: while temperature changes give clear CO2 changes (about 8 ppmv/°C), the influence of CO2 on temperature is undetectable, even as in the last start of the glaciation CO2 levels remained high while the temperature dropped to a new minimum. The subsequent drop of 40 ppmv had no discernable influence on temperature or ice sheet buildup. See:
http://www.ferdinand-engelbeen.be/klimaat/eemian.html
Thus the climate models overestimate the influence of CO2 on temperature to a large extent.
Phillip Bradley says:
When temperatures fell during the YD, CO2 just stopped rising.
====================================================
and phlogiston says:
It is curious how CO2 flatlined during the Younger Dryas.
====================================================
… there should be GCR/Solar activity proxies for the same period which can indicate what else
was happening.
I can see the sun waking up, or the GCR count dropping—or both—BEFORE the big melt started. The clouds roll back and the ice begins to melt. Then the CO2 starts to rise as the oceans warm …
There must be clues to the sequence.
Brilliant and I agree with those calling for this to be written up and published (if they will publish it). And I heard the media run with this as new proof. Simple clear science trashes the sophistry of data manipulation anyday. Occum wins again. I wondered why the CO2 line was truncated. Bravo Sir Bravo.
Why dont you average the proxy temperature records Willis?
“showing the difficulty of establishing whether CO2 leads or lags the warming.” Really?
My understanding is that (i) ages ago somebody (Antarctic ice cores?) calculated the cross-correlation function (CCF) between temperature and carbon dioxide so that this difficulty, which is visual not computational, is avoided
(ii) the CCF showed a best fit with CO2 lagging about 800 years behind temperature.
However I have not seen the working or worked it myself out for ice cores.
The CCF is a function of time, and is something like CCF(t)= integral_from_-∞_to+∞_of ( T(τ)C(t-τ)) dτ where T(t) and C(t) are the temperature anomaly and carbon dioxide anomaly at time t, and where great care is taken to get the signs right and the interpretation correct.
If T and C were perfectly correlated (e.g. identical functions displaced by a time X) the CCF would be zero everywhere except for a big spike at either time t=X (or -X: take care of the sign!) If there were no correlation the CCF would be a featureless noisy wobble. If there were no random factors, the CCF would be closely related to the impulse response connecting T and C (or vice versa). With random factors, the CCF would be this impulse response plus some random errors. It may be clear if the CCF is overall higher for t>0 than for t<0, and hence (with due regard to sign) whether T leads C or vice versa.
The CCF is a standard engineering procedure for finding impulse responses buried in noise and is computable in a few seconds, especially, using Fast Fourier Transforms and a programming langange, but is a bit fiddly with Excel!
Wandering off in conspiracy land again I see. You need to read Eric Wolff.
Poor guys, they probably worked more than a year on that article and it takes Willis a few days to rip it to tiny pieces. And poor as that the scientific standards have fallen to such a low level at Harward as well.
Correction: And poor us …
Thank you, Willis. Your ability to sniff out the tricksy, and then to present it so cleanly, is providing a hugely valuable service.
THe steep rise in CO2 in the graphs in Shakun et al seems to have beginning and end inflection points at about 17500 years and 11000 years, whereas in Willis’ graphs they are at 15500 and 9000. I was wonderiing how Shakun et al got a global temperature curve rising from about 17000 years bp to about 13500 bp, and then again from 12800 bp to 10000 bp, when the cloud of proxy dots does not coincide. Apart from any differences about interpretation of data, is there a straight-forward difference in plotted positions of datapoints?
Excellent, Willis.
Will the BBC publish a retraction of their support? Er, that’ll be no then.
Is that right – the chart shows the global temperature change from deepest ice age 15,000 years ago to today’s more pleasant levels is only around 2.5 degrees C?
Just about every other reference suggests it was around 6 degrees C, or am I not reading the chart correctly?.
Nice.
Where is the CO2-scale in the graph?
What are the different color points there?
The correct way is to submit a comment to Nature.
If the editor considers it reasonable (so, you must write it reasonably and there must be a scientist on the author list), it will be passed to peer review.
You might post the reviewers comments here as they are anonymous (yet one can always guess as in the Gleick case).
Nick Stokes says:
April 8, 2012 at 12:06 am
Their title is
“Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation”
Seems clear to me. And that’s what they plotted
Nick
I’m not sure if you meant this to be funny but i laughed a lot. It’s your best post yet. :))
Can’t open tips & notes
Front page of the Independent
http://www.independent.co.uk/news/science/exclusive-british-polar-research-in-crisis-7627014.html
“Exclusive: British polar research in crisis
The scientific body whose groundbreaking discoveries include the hole in the ozone layer is facing massive cuts as the Government’s austerity measures reach new frontiers”
suffolkboy says:
April 8, 2012 at 12:46 am
Thanks, Suffolkboy. You are correct. The question was studied in the ice core data, where both the CO2 and the ∂18O can be measured in the same bubbles. At that point you have a chance of determining the lag/lead of CO2 and ∂18O (a temperature proxy).
What Shakun et al. are claiming is that you can use pollen and Mg/Ca ratios and other proxies to overthrow the earlier studies that you reference. I think they cannot do that using their 80 proxies. The data is all over the map.
w.
Peter Miller says:
April 8, 2012 at 1:29 am
Thanks, Peter. I fear it’s choice B, not reading the chart correctly. The data is all standardized for intercomparison, so the units (as it says) are standard deviations.
In fact, the median warming among all of the 80 proxies is about 4 degrees. The warming for each individual proxy is given in Figs 4-8 in my previous post in this series, “Dr. Munchausen Explains Science By Proxy“.
w.
alex says:
April 8, 2012 at 1:31 am
Good questions, Alex. Both the temperature data and the CO2 data are standardized for intercomparison. So the scale for both is standard deviations.
The different colors are the records from different ice cores (Vostok, Dome C, Taylor, Dronning Maud, Law, etc.).
w.
Willis,
Nick has a pretty good point. Regardless of what has happened outside the period of their study, does the study show something that refutes an earlier understanding? For example, one might show temperature data describing a medieval warming period without any data before or after and with that alone challenge the characterization of our current warmth as “unprecedented.”
“How to lie with statistics” by Darrell Huff – the book deemed a must read for those entering advertising and marketing courses in the 70/80’s – like 1984, take it as primer or warning according to one’s own moral compass.
http://plus.maths.org/content/os/issue30/reviews/book4/index
http://www.jimloy.com/books/howtolie.htm
It was that background knowledge which first alerted me to the junk science – the very first example I was given was a graph giving temperature rise from a norm still in the Little Ice Age – and when I questioned the use of this point as the beginning was fobbed off with the Hockey Stick wipe-out of previous history..
Graphs showing solubility of gases in water
http://www.engineeringtoolbox.com/gases-solubility-water-d_1148.html
Willis Eschenbach says:
Thanks, Suffolkboy. You are correct. The question was studied in the ice core data, where both the CO2 and the ∂18O can be measured in the same bubbles. At that point you have a chance of determining the lag/lead of CO2 and ∂18O (a temperature proxy).
What Shakun et al. are claiming is that you can use pollen and Mg/Ca ratios and other proxies to overthrow the earlier studies that you reference. I think they cannot do that using their 80 proxies. The data is all over the map.
Thanks Willis, I’ve only been dipping in and out so may have missed that elsewhere, but I hadn’t realised that the CO2 lags data was far far superior to what I can only describe as utter carp … in other words: “run of the mills stuff for warmists”.
There is a point at which denying the sceptics valid and well supported position stops being “a matter of view” and starts becoming blatant fraud. Now that I understand the difference in quality of these two results and see the non-science being written based on all this hot air … I think they have crossed that line.
Keith says:
April 8, 2012 at 1:19 am
Good question, Keith. Their graphs are in years before present (1950). My graphs are in BC / AD, so the offset is about two thousand years.
Thanks,
w.
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.
Shakun’s Figure 4.2 is the money figure. This is from Figure 4.2 Legend: “(c) Atmospheric CO2 from the Dome C ice core (Monnin et al., 2001) on the Lemieux-Dudon et al. (2010) age model, which is the most recent and likely most accurate chronology. (d) Global mean temperature anomalies with 1σ errors due to chronological and proxy calibration uncertainties estimated from 1000 Monte Carlo simulations.” Later Figures showing CO2 trends refer back to Figure 4.2.
The Dome C ice core data shown in the Monnin, et al, (2001) Science 291, 112-114 (abstract page here, Figure only goes back to -9000 years before the present. Here’s the Monnin 2001 data archived at NCDC. The latest date is -9067 years BP. So, one wonders from where Shakun got the extra 2500 years of CO2 data shown in his Figures.
It turns out he must have gotten it here, which is another NCDC EPICA Dome C ice core data set that provides the Holocene (0-11KYrBP) Atmospheric CO2 all the way up to 435 years BP. It’s from Flückiger et al. 2002 “High-resolution Holocene N2O ice core record and its relationship with CH4 and CO2” Global Biogeochem. Cycles, 16(1), 1010, doi:10.1029/2001GB001417.
Between 10977 and 9899 years BP, the Monnin and Flückiger data sets overlap point-by-point, so they record the same data. And the Flückiger et al., 2002 data set reproduces Willis’ CO2 plot exactly. CO2 begins a steady rise at 6500 years BP, just where Shakun’s T:CO2 plot ends.
So, at the very least, Shakun used ~2500 years of the Flückiger data set without acknowledging it. And having that data set, he must have known about the rise in CO2 after -6500 years BP. And then truncated the CO2 record there, along with the temperature record.
In the text prior to his thesis Figure 4.2, Shakun wrote about the temperatures, “Temperature uncertainties (1 sigma) were taken to be 1.7C for TEX86 (Kim et al., 2008), 1.5 C for pollen and bioassemblages, 10% for ice cores (Jouzel et al., 2003), and are based on quoted calibration errors for Mg/Ca (Anand et al., 2003) and alkenones (Müller et al., 1998). We assumed temperature errors are random through time and among records, which is a maximally conservative approach as errors are likely autocorrelated..”
For those who don’t remember, random errors decrease by 1/sqrtN, where “N” is the number of records. This explains why the Shakun proxy temperature errors in his thesis Figure 4.2 are only (+/-)0.25 C, while the per-proxy errors are about (+/-)1.5 C. They’ve been averaged away as random uncorrelated error.
I assessed Jouzel’s Greenland ice core record. It displays less point scatter than any of his other published data sets, and displays at least two simultaneous error modes. This implies the error is systematic. The standard deviation of that error is 1-sigma=(+/-)0.5 C. As a systematic error, it does not decrease as 1/sqrtN.
Anand, et al., 2003, report a Ca/Mg temperature accuracy limit of (+/-)1.3 C. That’s accuracy, not precision. Accuracy limits do not decrease as 1/sqrtN. They propagate as sqrt[(sum of errors)^2].
Jouzel + Anand together, given equal weight, produce a joint accuracy limit of 1-sigma=(+/-)1.4 C.
Shakun’s Nature Figures 2&3 show proxy temperature uncertainty limits of (+/-)0.1 C over the entire 16,500 years of the record. This (+/-)0.1 C error is smaller than even in Shakun’s thesis, and about 1/10th of the limit of experimental accuracy in the the dO-18 and Ca/Mg temperatures.
The Figures live or die on that low level of T uncertainty. Increase it to a much more realistic 1-sigma=(+/-)1C and T overlaps CO2 across the full record. The entire lead-lag, T:CO2 relationship is lost.
So, Willis has again caught a good one. We have million dollar claims resting on truncated data sets and neglected error bars. Once again a triumph of climate-science and a bell-weather of Nature’s competence.
j ferguson says:
April 8, 2012 at 2:01 am
They claim to show something that refutes an earlier understanding, just as the title says.
Here’s what I observe.
1. The proxy data for all 80 proxies is given in their spreadsheet. It runs up as late in some cases as the 20th century.
2. The ice core data for the CO2 shown in their graphs is not given in their spreadsheet.
3. Despite the stated focus of the study on the glacial/interglacial transition, their CO2 data runs for 5,000 years beyond the end of that transition.
4. However, as soon as the CO2 data starts to diverge from the temperature data, it is cut off.
You are welcome to believe that this is just a cosmic coincidence, that it just shows that the gods have a sense of humor.
Me, I’ve been around agenda-driven climate scientists far too long to believe that. But don’t let me stop you.
Here’s the problem, j. If they show the full CO2 record, then they have to explain why the CO2 did all the things they claim it did during the transition, but then changed its ways after they cut off the record.
Look at Figure 2. For eight thousand years, CO2 has been rising fairly rapidly, and the global temperature has been falling. If they show that, their whole argument is threatened.
Now it is possible they just happened to cut the CO2 record off at that time, and it wasn’t related to the fact that showing it would torpedo their argument, and it just happened to be cut at the very time when the CO2 headed upwards … but my money’s betting the other way.
w.
Another excellent post Willis.
I think the key to examining the validity of their result is to look at the Younger-Dryas event. This instantly stuck me on looking at what they presented where it was occurring at a very different point in time to the Vostok record. Since they were not calling into doubt the timescale of Vostok this implies that they thought Y-D happened over 1000y later in Antarctica. So improbably that they do not suggest it overtly.
Now, seeing your digitisation of their reconstruction on top of the proxy data the deception becomes even clearer. They seem to be using processing with such a heavy damping (or there is so little resolution in the data themselves) that they have completely removed the dip in the Y-D event. This was a huge global event and the obvious key to resolving the key issue they purport to be examining.
The CO2 seems to have risen before the exit from Y-D because the data if failing to resolve it.
wmconnolley says:
April 8, 2012 at 12:48 am
—
I’ve had the joy of being able to work with mustelids for seven years- hence the name I use here- and I have to say: they are Smarter than you.
Another excellent analysis Willis. Keep slicing.
”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 …”
The opposite effect in the real atmosphere that CO2 is alleged to have in theory. Is that another aspect of the CAGW hypothesis crumbling that we hear? Yup.
@Willis
If this doesn’t gain traction I won’t beat it to death, but over at http://wattsupwiththat.com/2012/04/05/more-glacial-junk-science-journalism/#comment-948766 I have been calculating the absorption of CO2 by meltwater from ice sheets for KR and Daveo. If the atmospheric CO2 level has been approximately stable for the past 8000 years and the temperature has been dropping, then there may have been a continuous increase in the amount of ice volume (a difficult number to find).
When the sea evaporates and the precipitation freezes, CO2 is expelled into the air. As the oceans cool on a large scale they pick up more CO2 so there might an approximate balance between the CO2 expelled by new ice and the drawdown of the extra CO2 by the (cooling) oceans. This would give a constant CO2 level in a cooling world if ice volume continued to increase. It seems your plot shows that possibility.
On a shorter time scale, the expulsion of CO2 by snow and ice in winter would be countered by spring-summer melting and rapid uptake. This should show up as a cyclical variation in the CO2 concentration in the NH. Lo and behold it does. As the snow and ice cover in the SH is much less variable, the CO2 variation should be lower. Lo and behold. Random source: http://www.ferdinand-engelbeen.be/klimaat/co2_measurements.html#Variations_of_CO2_due_to_the_seasons:
A counter argument could be made that ice and snow ‘cover water’ and could prevent some uptake, but my HP calculator says that ice-sourced CO2 dominates. Yes I am aware that the annual variation has been attributed to land plants but the growth is inadequate and the (larger) CO2-ice argument is not addressed.
Your plot of temp and CO2 supports the idea that accumulating ice expells CO2 into the atmosphere, trumping absorption by cooling oceans. If the Antarctic ice cap is growing, the global rise of CO2 may well match the expulsion. The calculation is simple in round numbers because the air and oceans are both about 300-400 ppm.
If instead the ice sheets are melting, that meltwater will absorb huge quantities of CO2 (relative to human emissions) and the atmospheric level would decrease, just as it does in the NH each summer.
Who were the referees? Didn’t they look at the raw data? Does Nature have a shred of integrity left?
…
Joy, beautiful spark of the gods,
Daughter of Elysium,
Joy, beautiful spark of the gods
Spark of the gods!
Words from the poem ‘Ode to joy’ (Friedrich Schiller, 1785) and used in the finale of Ludwig van Beethoven’s choral symphony No. 9 in D minor, Op.125
Willis – is Nature obliged in any way to publish this? Not sure if that’s the best choice of wording, are there precedents under which they’re obliged to publish?
Willis, thanks for the clarification on timescales. This still begs the question how did Shakun et al calculate their global temperature curve? It doesnt look like an average of the temperature data points. Did they weight the ice core isotopic data? Something pulls their line to the right particularly between 17500 bp and 13500 bp. The data cloud says their temperature curve should start to rise around 19000 bp rather than 17500. It looks like it should also go to a higher temperature around 13000 – 14000 bp. THese 2 effects would put their temperature curve to the left of the CO2 curve at least in the time period 19000 – 13000 bp
Willis,
Thanks for the expansion. It bothers me that there actually might be an intention to mislead.
The second graph, described by the text as CO2 levels, has a Y-axis labeled as temperature. Did someone forget to relabel the text in their script before generating the graph?
Willis Eschenbach says:
April 8, 2012 at 2:46 am
“Look at Figure 2. For eight thousand years, CO2 has been rising fairly rapidly, and the global temperature has been falling.”
Average it so we can see that..
It is going to take more science on your part then what you offer. The simple fact that over the last ten thousand years CO2 has risen a little over 15ppm speaks for itself. Also the fact the Northern and Southern Hemispheres comes into to temperature alignment at the time of the mild CO2 rise and temperature decrease also makes for an interesting study. (http://i39.tinypic.com/f0qkcw.jpg)
Willis:
Excellent deconstruction. Do we know what CO2 source data they used and how that matches up against the NOAA source data?
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?
Willis:
Ignore my previous question since you answered it in the preceding reply. Is there anything we can guess on the source of their CO2 data based on their other research or from the article. Shakun et al. make strong assertions while basing it on fuzzy proxies for temperature and without providing the source of their CO2 data. They make an end of discussion assertion with pretty sketchy data – how fuzzy is that?
Yeah, some of the AGW crowd also claim that farming since about 10,000 BC has increased c02 in the atmosphere, delaying the onset of the next ice age.
They claim that the Holocene has been warmer than it should have been (even though the temperature has been dropping), and also longer than it should have been, due to farming and clearing. But to my mind these claims are not supported by the facts.
1. The Holocene has been cooler than previous interglacials. With the human c02 effect, it should have been warmer.
2. The length of the current interglacial is not unusual (we should be slipping slowly into an ice age over the next few thousand years or so).
R
If that CO2 record is really that damped (as a physical phenomenon) to the point where it fails to capture Y-D it can hardly be regarded as driving temperature change as the paper claims.
The paper clearly shows (Because they average the proxy records) that CO2 leads temperature change then drops below it http://i39.tinypic.com/f0qkcw.jpg.. Showing that CO2 should rise again to match temperatures, which it does as shown in your graph. But because you don’t average the proxy temperature records you cant see that..
Great catch Willis!! I had an inclination there was something in there…And for some reason, I can’t get a famous phrase out of my head when I come to Fig 2: “Can you tell what it is yet?” (Rolf Harris) 🙂
wmconnolley says:
April 8, 2012 at 12:48 am
Wandering off in conspiracy land again I see”
xxxxxxxxxxxxxxxxxxxxx
Ha ha ha ha.
WARNING: Now that we’ve read your unwitty comment – intelligent minds will need to brain shower.
Reblogged this on Climate Ponderings and commented:
It was Twicksy
Willis
Fascinating stuff.
You show the temperature data. Did you also plot the co2 ppm figure? If it was 280ppm at the pre industrial period what is it now, and back when the rise started?
tonyb
There is also the uncertainty associated with the age determination – which would be (in my view) a more likely place for confirmation bias to creep in. It is difficult on paired analyses to be sure – but correlation of proxy to proxy is probably a bit of a judgement call.
For example – one could anchor all of the proxies at the point of greatest change with the assumption that the change was global and instaneous – and then see how / if the CO2 in anchored samples preceeded the temperature change.
Just a thought.
Great work Willis.
I wonder if the Shakun 2012 CO2 source data did have values for the period between 5000 BC and the present? As you say it is not included in their spreadsheet. If so then it’s hard to imagine any legitimate argument to justify omitting that period. Other than the bleeding obvious of course.
Sounding more and more like yet another team effort?
To paraphrase Prof Jones: “I’ve just completed an alike Nature trick of not adding CO2 proxies to the proxy temps for the last 500 years to hide the incline.”
Classic piece of research checking to ask the question ‘what was left out and why ‘ , its one of those idea that should be taught to any undergraduate. Its failure to occur in this paper peer review is a further reminder that the ‘best ‘ of the science in this area is not even off a standard acceptable for undergraduates essay in any decent university.
That is partly why its so funny to be told that you have to ‘trust’ the science , given the standards in this area are normal so poor , we should anyone actual trust it when its little better than the academic version of ‘what my mate in the pub said’ ?
To paraphrase Prof Jones: ” I have just complered another Nature trick of not adding CO2 proxies to the proxy temp for the last 5000 years to hide the incline.”
To paraphrase Prof Jones: “I have just completed another Nature trick by not adding the CO2 proxies to the proxy temps for the last 5000 years to hide the incline.”
At my comment:
major9985 says:
April 8, 2012 at 3:30 am
The link was meant to be:
http://i44.tinypic.com/34gncox.jpg
My comment at
major9985 says:
April 8, 2012 at 3:30 am
the link was meant to be:
http://i44.tinypic.com/34gncox.jpg
alex says:
April 8, 2012 at 1:34 am
“The correct way is to submit a comment to Nature.
If the editor considers it reasonable (so, you must write it reasonably and there must be a scientist on the author list), it will be passed to peer review.”
Agree, a Comment published by Nature would correct Shakun’s cherry-picking. But since Nature is now motivated by politics over science, I would not expect any such Comment to see the light of day. Like Mann, Shakun is telling them what they want to hear.
That said, it is certainly worth a try, just for the record.
Posted on April 7, 2012 by Willis Eschenbach
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 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.
Each ONE ice core record is unique, Vostok or Bond et al. The truth of describing nature is not to be greater, if individual records are cooked in statistics lump everything together.
If one has the idea that a gas creates heat of saw tooth oscillations ~8° Cel. on Earth over million of years, he may show it by physics. If one has an idea what creates heat of saw tooth like oscillations ~8° Cel. on Earth over million of years, he may show it by physics. A comparison of both is a specious argument and not at all bad science; it is not science.
It is possible to study the unique global records (plural), and you can find phase correlations in the (few) spectra. Each increase of global temperature proxy is powered by a heat source and each saw tooth like frequency has its very own geometry of the heat oscillator.
It is well known here that as well high frequency global temperature oscillations as measured by UAH but also very low frequency global temperature oscillations as recorded in Vostok or by Bond et.al. 2001 have agreements with specific solar tide functions in phase and frequency. The latter can be shown in four graphs because of the big time interval:
http://www.volker-doormann.org/images/vo_m4k.gif
http://www.volker-doormann.org/images/vo_m10k.gif
http://www.volker-doormann.org/images/vo_m15k.gif
http://www.volker-doormann.org/images/vo_m30k.gif
It is one thing to fight against stupidity in the CO2 war, but it leads the scope away from the question what physical processes vary the heat source by which geometries.
An alternative may to verify each anonymous green dot in the graph for correctness. Seems to be a funny job if there are only bad News from xyzgate soaps.
Science is to show agreements in nature, not to being skeptic on possible agreements, because skeptic is not a method of science.
V.
“The enemy is not the CO2, the enemy is you!”
(unknown)
Willis Eschenbach says: April 8, 2012 at 2:46 am
“If they show that, their whole argument is threatened.”
Not at all. Their argument, at least as stated in the abstract, is:
“These observations, together with transient global climate model simulations, support the conclusion that an antiphased hemispheric temperature response to ocean circulation changes superimposed on globally in-phase warming driven by increasing CO2 concentrations is an explanation for much of the temperature change at the end of the most recent ice age.”
They are explaining a specific event, and presented graphs that showed that period.
Nick Stokes says:
“They are explaining a specific event, and presented graphs that showed that period.”
As Willis shows, Shakun et al. were blatantly cherry picking.
Nick Stokes’
The data shows it could go either way. You need to Cherry pick to claim Co2 leads temp.
I had a sneaking suspicion that Willis would come back to this paper. What he has found is similar to hide the decline. Where the authors aware of the rise after their cut-off date?
Willis should send his findings to Nature and see what they have to say about it.
It just goes to show that with enough funding you can make almost any climate related scientific claims you want.
Phillip Bratby says:
April 7, 2012 at 11:41 pm
See “Dishonest, Delusional and Dangerous” – Piers Corbyn dismembers the latest Nature magazine claim propagated by BBC that CO2 drives climate.
http://www.weatheraction.com/docs/WANews12No20.pdf
—————————————
Hi Willis,
could you make a plot with different colours for northern/southern hemispheric data to support/reject Corbyn’s analysis ?
I did a similar analysis of the ice core data with similar results. I observed the proxie temperature deviation beginning around 4000 BC. For a likely explanation of why, see http://www.kidswincom.net/climate.pdf.
Like I said earlier: That Shakun-paper should be withdrawn. This piece clearly shows why.
I hate it when scientists leave the inconvenient parts out. That’s misleading and again it shows “pal-review” at its best.
I definitely never going to subscribe to Nature whatsoever.
To Willis Eschenbach: Are you going to try to convince Nature to withdraw the Shakun-paper?
All this is handwaving unless you write a letter of Comment to Nature and they withdraw the paper
j ferguson says:
April 8, 2012 at 2:01 am
You would have a point if the paper wasn’t trying to turn over such an important theme – that temperature lagged CO2 rise at the end of the last glaciation and therefore CO2 caused the temperature increase. Assuming Shakun et al had the extra CO2 data it shows that CO2 can rise without any temperature increases (a direct contradiction to their central argument) and that CO2 has been rising for 8,000 years, not just since man started burning fossil fuels (a direct contradiction to the heart of AGW).
Nice work Willis. You should publish this. You should also show single graphs of temperature versus year for Greenland and the Antarctic because they clearly show the Antarctic warming up almost 2,000 years before Greenland (there is no way the NH caused the SH to release CO2 to warm the SH).
Someone suggested averaging the time series but if you look at the individual proxies some of them don’t look real and others are neither correlated to Greenland or to Antarctica – so what would you expect from this averaging process?
Anthony,
I think WUWT may be under attack. If I scroll down several screens, I get redirected to a blank WUWT page and can’t get back. This is happening only for WUWT for me, which is why I think it’s directed specifically at you. I’m using IE 9.0.5. (Firefox 10.0.2 is OK for now.)
Good luck.
Bob
Has Willis’ observation that CO2 proxies have generally shown an increase in CO2 beginning 6000BC while temperature proxies have generally shown a decrease in temperature since 8000BC been made before? If so, why isn’t this one of the top 5 arguments to cast doubt on the CAGW hypothesis?
Stokes argument that it was quite right to leave out the later CO2 records because the investigators were focusing on a relatively narrow time period is specious. The writers were using data to hypothesize a mechanism to explain events at a particular time. If that same data extended casts doubt on that hypothesis, a scientist must include that data and explain how the hypothesis is still valid.
Of course Willis explained yesterday why the temperature proxies cannot be averaged – hence the hypothesis is not based on anything scientific to begin with.
Back to my main point – why has the gross relationship of the temp and CO2 proxies over the last 10,000 years not been a prominent argument (that laypeople can understand) casting doubt on the warmers?
Thank you WIllis, excellent postings that resulted in the deconstruction of the paper.
Shakun’s explanation itself was already smelling bad: ice melted first, but that was not global warming, no changes in albedo through ice melting but changes in ocean currents. So North Hemisphere melts ice but it is only South Hemisphere warming which releases CO2 which then creates global warming.
Nick Stokes says:
Willis Eschenbach says: April 8, 2012 at 2:46 am
“If they show that, their whole argument is threatened.”
>> Not at all. Their argument, at least as stated in the abstract, is:
“These observations, together with transient global climate model simulations, support the conclusion that an antiphased hemispheric temperature response to ocean circulation changes superimposed on globally in-phase warming driven by increasing CO2 concentrations is an explanation for much of the temperature change at the end of the most recent ice age.”
>> They are explaining a specific event, and presented graphs that showed that period.
When papers start using phrases like “support the conclusion that …” they are saying they have not proved anything, simply that there is not blatant contradiction with what they are saying. ie yet more unsubstantiated hypothesis. Why these kind of non results are considered worthy of begin published is more to do with politics than science.
Anyone can publish “results” about unproven ideas not being disproved because they and have not tried hard enough and have chosen to ignore half the data that would have disproved them.
If they were then to explain why their “anti-phase” plus in-phase combo becomes “anti-phase” plus “anti-phase” in the last 5000 years we may have something to talk about.
As it is, this is just more IPCC fodder and cargo cult science. Your rather ridiculous attempts to claim it means anything just shows how blinkered you are yourself.
Can picture them now, “And we would have got away with it too, if it wasn’t for that meddling Willis!”.
Great work.
Affizzy, what makes you think they would withdraw the paper?
Nick, you should be questioning your deeply held beliefs.
Most of the time period covered here is like the previous nearly 400,000
years, where few warmists heavily dispute CO2 lagging temperature. During
that time, the total of atmospheric, hydrospheric and biospheric carbon was
constant, and atmospheric CO2 content was one of the positive feedbacks.
But once humans started transfering carbon from the lithosphere to the
atmosphere, increase of CO2 became a cause of warming. It appears to me
that the debate should be over how much or how little, rather than whether it
does or does not.
I have done research of my own, leading me to findings of modern global
climate sensitivity ranging from .67 to 1.5 degree C/K per factor-of-2 change
of CO2, and decreasing as global temperature and greenhouse gas
presence increase. This is much less than figures advocated by most
advocates of existence of manmade global warming via CO2.
But before I got that far, I handled debate as to whether CO2 was higher
during WWII than now, whether nature has recently been adding or removing
CO2, and cherrypicked 10, 11, etc. year parts of global temperature record
beginning with a century class El Nino and ending with a La Nina. When the
debate I handled was along those lines, I thought that manmade CO2 causing
global warming meant causing *as much* warming as advocated by most
advocates of manmade CO2-caused global warming.
I like the way that. around -11000, there is a sharp dip in the temperatures and the CO2 responds! I think Shakun must be a’shakun’ that he has been rumbled.
Seriously, when do these people stop trying to support this edifice of delusion and illusion.
LOL
Great find and interesting post Willis! Thanks, William.
The Greenland Ice sheet temperature data and record of CO2 supports your finding and posting. CO2 rises throughout the 6000 year period while temperatures drift down. The ice sheet data also shows the Dansgaard/Oeschger cycles (also referred to as Bond Cycles) which are cycles of warming and cooling. Obviously CO2 does not cause Dansgaard/Oeschger cycles of warming and cooling. Bond noted in his published research that the cycles have a 1500 year period and that there are concurrent cosmogenic isotope changes that occur at the same time as the warming and cooling.
The 20th century warming appears to be a Dansgaard/Oeschger cycle as it correlates with a large solar magnetic cycle change.
http://climate4you.com/images/GISP2%20TemperatureSince10700%20BP%20with%20CO2%20from%20EPICA%20DomeC.gif
http://climate4you.com/
Fig.3. The upper panel shows the air temperature at the summit of the Greenland Ice Sheet, reconstructed by Alley (2000) from GISP2 ice core data. The time scale shows years before modern time, which is shown at the right hand side of the diagram. The rapid temperature rise to the left indicate the final part of the even more pronounced temperature increase following the last ice age. The temperature scale at the right hand side of the upper panel suggests a very approximate comparison with the global average temperature (see comment below). The GISP2 record ends around 1855, and the red dotted line indicate the approximate temperature increase since then. The small reddish bar in the lower right indicate the extension of the longest global temperature record (since 1850), based on meteorological observations (HadCRUT3). The lower panel shows the past atmospheric CO2 content, as found from the EPICA Dome C Ice Core in the Antarctic (Monnin et al. 2004). The Dome C atmospheric CO2 record ends in the year 1777.
The past temperature changes show little (if any) relation to the past atmospheric CO2 content as shown in the lower panel of figure 3. Initially, until around 7000 yr before now, temperatures generally increase, even though the amount of atmospheric CO2 decreases. For the last 7000 years the temperature generally has been decreasing, even though the CO2 record now display an increasing trend. Neither is any of the marked 950-1000 year periodic temperature peaks associated with a corresponding CO2 increase. The general concentration of CO2 is low, wherefore the theoretical temperature response to changes in CO2 should be more pronounced than at higher concentrations, as the CO2 forcing on temperature is decreasing logarithmic with concentration. Nevertheless, no net effect of CO2 on temperature can be identified from the above diagram, and it is therefore obvious that significant climatic changes can occur without being controlled by atmospheric CO2. Other phenomena than atmospheric CO2 must have had the main control on global temperature for the last 11,000 years.
Willis: I’d add my voice to getting someone on board with you, perhaps Dr. Spencer or someone like that, and condense this down and send it to Nature. The odds are that Nature will not accept it, but the act of getting it polished and condensed for submission will improve it and make it more powerful.
Willis, all your postings are excellent and the last two are no exceptions. This last one I doooo like as it does not leave much room, if any, for the idea that a doubling of CO2 can, will or does contribute to “maybe” 1 °C of atmospheric warming (biased little me).
Looks like you may be one of those “heretics” who are giving skeptics like Fred Singer a bad name, however it may just be true that a wise person waits until all the “available evidence” has been analysed before he (or she) apportions blame.
It appears to me that the debate should be over how much or how little, rather than whether it does or does not.
Anthony would agree. So would Lindzen. Monckton, too, for that matter. The real debate centers around feedbacks.
One will note that the actual instrumental record is being called into considerable question. it is possible that 20th warming, itself, is exaggerated (perhaps by a factor of two).
I handled debate as to whether CO2 was higher during WWII than now,
It once seemed to me that it must have been higher. Industry was going full guns (“Spare Gas fur Rusting”) and a hundred major cities were incinerated or blasted to bits. But OTOH a lot of the oil and coalfields were in the combat zone, and a lot of the labor force was at the front. Proxy records show a slight CO2 drop during the height of the war as compared with 1940. After all, I’m not sure i know what to think.
In re …
wmconnolley says:
April 8, 2012 at 12:48 am
*******
There have been two quite juvenile responses to wmconnelley’s link and its contents.
Perhaps a more mature comparison and analysis of his views with those of Willis would be useful … particularly to those of us who are not scientifically-inclined.
Many thanks.
Pedro
Willis is simply not showing you that the Southern Hemisphere warmed first, while the Northern Hemisphere slowly caught up over 8000 years.. This is why he says the proxy records are all over the place and he shows them all together http://wattsupwiththat.files.wordpress.com/2012/04/nature_shakun_proxies_plus_co2.jpg
When you average out all the Northern Hemisphere Proxy’s and compare them to the Southern Hemisphere Proxy’s as shown in this graph http://i44.tinypic.com/34gncox.jpg you can see why some of the proxy’s have a late warming start. These proxy’s are not cherry picked, it is just the simple fact that the Hemisphere’s warmed at different times and the proxy’s show that. Here is a graph of all the proxy sites used to get a global temperature average http://i41.tinypic.com/1432dtw.jpg
If you average out all the proxy records to get a global average you can very easily see that temperatures trail CO2 http://i39.tinypic.com/f0qkcw.jpg and as you can see (because the proxys have been averaged in the graph, not like Willis) temperatures keep on going up as CO2 levels off. This temperature/CO2 division is miniscule and is easily seen on any Holocene temperature/CO2 graph http://www.geocraft.com/WVFossils/PageMill_Images/image357_lg.gif even when compared to multiple temperature records, the Holocene is flat in line with CO2 http://ossfoundation.us/projects/environment/global-warming/myths/images/temperature-records/Holocene_Temperature_Variations_Rev.png
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:
http://www.nature.com/nature/journal/v484/n7392/full/nature10915.html
“Climate sensitivity is not constrained by the last two decades of imperfect satellite data, but rather the paleoclimate record.”
NASA climatologist Gavin Schmidt
Well Willis, you have estimates of [CO2] and ‘global’ temperature estimates. A plot of Ln([CO2]) vs Temperature will give you a slope, with error-bars in two dimensions, that will give you the ‘climate sensitivity’.
Of course, on will find that CO2 is not directly coupled to temperature, and the directionality of temperature change give two estimates of ‘climate sensitivity’.
Congratulations to WUWT/Willis Eschenbach for providing the raw material for *TWO* articles!
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Part I: WUWT/Eschenbach verify
the deglaciation CO2/temperature relations of Shakun2012
In a reanalysis of the data used by Shakun et al. in their “Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation” (Nature, 2012), WUWT/Eisenbach have affirmed the main conclusion of Shakun et al:
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Part II: WUWT/Eschenbach verify
the CO2/temperature “Hockey Stick” of Mann1999
Extending the data used by Shakun et al. in their “Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation” (Nature, 2012) to encompass the anthropocene era 5000BP–present, WUWT/Eisenbach have affirmed the main features of the CO2/temperature “Hockey Stick” of Mann et al: in “Global-scale temperature patterns and climate forcing over the past six centuries” (Nature, 1999):
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
But Willis, to see this clearly, your data plots have to include *all* the temperature proxies, and *all* the CO2 data, for the *complete* period 5000BP–present. Because if you’re going to criticize Shakun et al. for not showing all their data, and for truncating their time series arbitrarily, aren’t you thereby obligated to show all of *YOUR* data?
To phrase this same point positively, Willis … you’ve already done a terrific service to both the skeptical and the scientific communities, by verifying the good analysis that Shakun et a: made of CO2/temperature relations during the last deglaciation (22000BP–6000BP), during which time the “main event” was the melting of the glaciers. Now you have a fine opportunity to repeat that analysis for the period (600BP–present), during which time the “main event” is the “hockey stick” of CO2/temperature.
This analysis, affirming both the mutual forcing of CO2 and temperature, and the reality of the 20th-21st century “Hockey Stick” in both quantities, would go far toward building a bridge of mutual appreciation and trust between skeptics and scientists— from which our entire planet would benefit.
So go for it, WUWT/Willis! Assure us that forcing is real, and so is Mann’s Hockey Stick!
Lincoln,
I’ve done what you are asking Willis to do. Read http://www.kidswincom.net/climate.pdf with an open mind and objectively come to your own conclusions.
Willis, the sheer time and effort you put into every single one of your posts is astounding. Highly informative, and above all; follows the classical scientific method.
Your work is highly appreciated and readable. Thank you.
Nice work Willis, but can I suggest (even on Easter Sunday) that if you do send this as a comment to Nature that you use BP (i.e. calibrated years pre-1950) rather than BC, and you explicitly note which of the calibration data sets this is based on (i.e. was it IntCal04 or IntCal09?), and how this influences results. IntCal09 tends to give somewhat older pre-Holocene ages than IntCal04.
Something tells me the Holocene CO2 concentration increase has been successfully dealt with in other papers. If nothing else, there’s ongoing change of Earth orbital parameters and the change in CO2 concentrations was several orders of magnitude slower than the change we’re usually discussing now, it can’t be told how exactly would it look like if the CO2 concentration didn’t increase over the Holocene. Maybe we’d be deep in another ice age already without it? I can’t really tell, but this is what I found discussing the matter:
http://ruby.fgcu.edu/courses/twimberley/EnviroPhilo/Steig.pdf
“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.”
Since Rio+20 is coming up soon, I’m expecting a lot more of these types of peer reviewed reports in the coming months. I wouldn’t be surprised to see some of their now discredited wild claims come back to life in new reports and papers.
It looks like:
for that data to see that no fit is resolvable from a zero-trend straight line.
a) The CO_2 “rise” it shows starting at 20 Kya is utterly spurious. CO_2 was utterly flat (to falling a little) from 25 Kya to 15 Kya. I don’t need to compute
b) As always, the Younger Dryas has much to tell us. If CO_2 is responsible for the warming trend in a positive feedback cycle, then it should have pulled the temperatures up across the YD instead of following the temperature curve down. Although as noted it looks like the YD signal is very attenuated in much of the coastal tropical data and is prominent only in the Antarctic cores. The CO_2 looks like it follows the tropical (much subdued) signal.
c) The Holocene Optimum was an easy 0.5 K warmer than today. Since then, the mean temperature has steadily dropped, while CO_2 has increased with a clear crossover. Conclusion: CO_2 variation isn’t a highly sensitive driver, or the main driver, of global temperatures. Secondary conclusion: Something else is!
While I am happy to believe that the bistable oscillations observed over the last half million or more years are coupled to astronomical cycles, that does not suffice to explain the bistability. There is a causal factor missing. I don’t think it is closing off of circulation patterns in the ocean because the effect isn’t sufficiently discrete for that (on the 5 million year scale). The temperature doesn’t plunge down, it very steadily drops. This is a knob being turned, not a door being slammed shut. Furthermore it is a knob that has been turned before, back when today’s continents were a distant event in the future. It’s not inconceivable that ice ages are caused by continental drift but the data makes it somewhat implausible.
It would be very, very interesting to look at Mars or Europa or any other planet with an accessible thermal history to see if there is evidence of Martian heating and cooling on the billion year timescale that matches that of the Earth’s. That would be direct evidence that the Sun itself is very long period variable in some way that might explain it. Perhaps it is connected with times that the solar system drifts through interstellar dust clouds and the sun is slowly “fed” with infalling matter, and when it drifts out the sun returns to a slightly cooler steady state.
But even that wouldn’t fully explain the bistability.
rgb
says:
April 8, 2012 at 7:17 am
In re …
wmconnolley says:
April 8, 2012 at 12:48 am
*******
There have been two quite juvenile responses to wmconnelley’s link and its contents.
Pedro~ We are speaking of a person who has distorted the biographies of many skeptic scientists, to smear their reputations and their efforts in climate science.
We are speaking of a person who has made changes to over 5000 climate articles, to bolster support of his religion, ie, AGW.
We are speaking of a person who had either blocked or banned several hundred people from wikipidea, either because they were trying to post scientific pieces that ran counter to his faith, or because they were trying to correct egregious errors he wrote into their pieces.
And you want us to listen to what he has to say, because………?
Pete says:
Perhaps a more mature comparison and analysis of his views with those of Willis would be useful … particularly to those of us who are not scientifically-inclined.
All wmconnolley did was link to a page that opens with this,
It is indeed a very fundamental question about whether the CO2 leads or lags the temperature. If there was somewhere in the ice core record where CO2 increases and temperature does not, then our understanding of the greenhouse effect must be faulty. However, so far we don’t find such a place.
Now go look at Figure 2 above and the question is answered. CO2 has increased for the last 6,000 years and temperatures have not. Ergo, their understanding of the greenhouse effect is faulty.
Its just the usual obsfurcation from warmists like wmconnolley. Post a link and rely on the fact 95% of people won’t follow it or understand it. Real Climate does this all the time.
Nick Stokes wrote:
“Their title is “Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation” Seems clear to me. And that’s what they plotted.”
That’s really what they plotted? Then why didn’t they stop plotting the graphs at 10K BP, which would be the beginning of the Holocene? Their graphs all end at <7K BP which goes beyond the last deglaciation.
Re: Pete
From the very first paragraph of the link pointed to by wmconnelly
I believe Willis’s figure 2 shows just such a place where CO2 increases without a temperature rise.
As a dynamicist, I was intrigued by the ‘high frequency’ transient in some of the proxy data that has a positive peak around -12k yrs and a negative peak around -10k years. I would love to see someone correlate that with other events during that era.
The rise is about 10 ppm in that last period which would lead to 0.1 C of temperature increase, so it might be hard to see. The modern era was truncated off the right side of this graph, but it would currently be about 3 on that scale moving to somewhere near 10 by 2100, just to put it in perspective, so are we concerned about that little ramp of 10 ppm?
Pete says:
April 8, 2012 at 7:17 am
There have been two quite juvenile responses to wmconnelley’s link and its contents.
=============================
“Thus there is no surprise in the idea that the end of the ice age was kicked off by something other than CO2. however once it started, CO2 appears to be involved in keeping it going.”
…..yep, CO2 forced it right into another ice age
Willis is simply not showing you that the Southern Hemisphere warmed first, with the Northern Hemisphere slowly catching up over 8000 years.. This is why he says the proxy records are all over the place and shows them all together http://wattsupwiththat.files.wordpress.com/2012/04/nature_shakun_proxies_plus_co2.jpg
When you average out all the Northern Hemisphere Proxy’s and compare them to the Southern Hemisphere Proxy’s as shown in this graph http://i44.tinypic.com/34gncox.jpg you can see why some of the proxy’s have a late warming start. These proxy’s are not cherry picked, it is just the simple fact that the Hemisphere’s warmed at different times and the proxy’s show that. Here is a graph of all the proxy sites used to get a global temperature average http://i41.tinypic.com/1432dtw.jpg
If you average out all the proxy records to get a global average you can very easily see that temperatures trail CO2 http://i39.tinypic.com/f0qkcw.jpg as you can see in the graph temperatures keep on going up as CO2 levels off. This temperature/CO2 division is miniscule and is easily seen on any Holocene temperature/CO2 graph http://www.geocraft.com/WVFossils/PageMill_Images/image357_lg.gif even when compared to multiple temperature records, the Holocene is flat in line with CO2 http://ossfoundation.us/projects/environment/global-warming/myths/images/temperature-records/Holocene_Temperature_Variations_Rev.png
There are cycles of warming followed by cooling and occasionally abrupt cooling that has a period of 1470 years +/- 500 years. The 8200 year BP abrupt cooling event, the Younger Dryas 12,900 BP year cooling event, 4200 year BP cooling event and so on follow this cycle. The Greenland ice sheet data show that atmospheric CO2 isn’t the driver of the Bond cycles and in fact does not change in response to the planetary temperature change.
Bond cycles, ≈1,470 ± 500 years, recorded in the Greenland ice sheet data.
http://climate4you.com/images/GISP2%20TemperatureSince10700%20BP%20with%20CO2%20from%20EPICA%20DomeC.gif
http://climate4you.com/
http://en.wikipedia.org/wiki/1500-year_climate_cycle
Bond events are North Atlantic climate fluctuations occurring every ≈1,470 ± 500 years throughout the Holocene. Eight such events have been identified, primarily from fluctuations in ice-rafted debris. Bond events may be the interglacial relatives of the glacial Dansgaard–Oeschger events, with a magnitude of perhaps 15–20% of the glacial-interglacial temperature change.
Gerard C. Bond of the Lamont-Doherty Earth Observatory at Columbia University, was the lead author of the paper published in 1997 that postulated the theory of 1,470-year climate cycles in the Holocene, mainly based on petrologic tracers of drift ice in the North Atlantic.[1][2]
The existence of climatic changes, possibly on a quasi-1,500 year cycle, is well established for the last glacial period from ice cores. Less well established is the continuation of these cycles into the holocene. Bond et al. (1997) argue for a cyclicity close to 1470 ± 500 years in the North Atlantic region, and that their results imply a variation in Holocene climate in this region. In their view, many if not most of the Dansgaard–Oeschger events of the last ice age, conform to a 1,500-year pattern, as do some climate events of later eras, like the Little Ice Age, the 8.2 kiloyear event, and the start of the Younger Dryas.
http://sheridan.geog.kent.edu/geog41066/7-Overpeck.pdf
ABRUPT CHANGE IN EARTH’S CLIMATE SYSTEM
“The earliest Holocene abrupt climate changes occurred at 12,800, 8200, 5200, and 4200 B.P. . . .”The 8200 B.P. event, “lasted four hundred years (6400-6000 B.C.) and, like the Younger Dryas, generated abrupt aridification and cooling in the North Atlantic and North America, Africa, and Asia (Alley et al. 1997; Barber et al. 1999; Hu et al. 1999; Street-Perrot and Perrot 1990).
http://www.geo.arizona.edu/palynology/geos462/8200yrevent.html
The 8200-year Climate Event
http://www.ldeo.columbia.edu/~peter/Resources/Holocene.vs.Stage5e.html
– The Holocene was punctuated by irregular 1500±500 year cooling events which have correlatives in the North Atlantic (deMenocal et al., 2000; Bond et al., 1997).
– When compared to the Holocene sequence at Site 658C, the results suggest we are overdue for an abrupt transition to cooler climates, however orbital configurations These results are consistent with other high-resolution records of the Last Interglacial from the North Atlantic and support the view large-scale climatic reorganizations can be achieved within centuries.
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. However, the authors over-state their case saying that CO2 leads temperature.
My big critism would be that they should have ended both data sets at the same point, leaving the recent past to someone else’s endeavors. Nick, you would have to agree with me on this point at least.
Pat Frank’s comment at April 8, 2012 at 2:38 am is perceptive and important.
If the Monnin data was padded with only the convenient data from Fluckinger, that is indeed damning.
“…I leave everyone to ponder how far climate “science” has fallen…”
In the end, they will have carried the flag in support of bankrupting the world and this country. And in that end will themselves meet their own end.
The most ridiculous and irritating consequence is in the meantime all that money could be going to science that would have a positive impact on our lives rather than to the villainizing of CO2 crap you so properly reveal.
Manfred (April 8, 2012 at 5:35 am) linked to Piers Corbyn’s note on statistical paradox: http://www.weatheraction.com/docs/WANews12No20.pdf
—-
Phillip Bratby (April 7, 2012 at 11:41 pm) responded: “Hi Willis, could you make a plot with different colours for northern/southern hemispheric data to support/reject Corbyn’s analysis ?”
—
Careful as follows if/when you do this Willis:
The current distribution of continents is NOT symmetric about the equator.
Earth’s asymmetric.
The equator is NOT the fulcrum for all key variables.
The sharpest gradients are over the Southern Ocean.
Here’s a visual reminder based on recent decades:
_ Isotachs & Pressure at 550K: http://i56.tinypic.com/14t0kns.png _
How about trying to understand the issues and making your own arguments. It seems to me that Wolff’s criticism doesn’t apply here. Here’s what Willis said in a previous comment:
wmconnolley, intellectual laziness such as what you just demonstrated is what turned me into a skeptic. There was a guest post on boingboing in which the author attacked the hockey stick because there was plenty of historical evidence that the MWP happened. The best the permanent editors could do was point to an article somewhere else and assert that the hockey stick was valid. In that very moment the skeptic in me was born.
What you are doing, by pointing to Wolff, is confessing that you don’t understand the issues. You could at least try, otherwise we will all think you are just a garden variety troll.
Actually, figure 2 above is labelled temperature.
Willis, perhaps you will consider signing your posts as “Trixie?”
Having had first hand experience with a challenge of extremely poor science being published in Nature, I suggest Willis give them a very brief chance to retract the Shakun 2012 paper. Give them the above information and suggest immediate publication of your analysis of the paper in question or the retraction of the offensive paper.
In my case (Nature rejected our rebuttal stating it was too long if you can believe it) it wasn’t until the original paper was deconstructed by several groups and other journals published papers (including ours) demonstrating the serious flaws that eventually Nature did disavow the original paper.
I further suggest a landslide of comments to Nature from anyone who values real science, and see if (but probably when) Nature will reject your rebuttal of the Shakun 2012 paper,
I strongly suggest Willis seek publication in another journal and then wait for the further disgrace of the original peer review at Nature to be aired.
Once again Real Science takes another shot and its credibility suffers at the hand of the AGW team. Pity
Lincoln Sparrow, you seem capable of elucidating us on scientific method. So I will point out that 1) the words in the conclusion you quote includes oceanic circulation affects but this was not a part of the study, and that 2) you seem willing to speak of the word used by the authors -“generally”- as a statistical finding. The paper does not appear to support this word as a statistical finding (generally statistical findings are included in the section called “Results”). Might this word have been used by the authors when error bars and tests of statistical significance did not show promising results?
“I have further exhibits, but I hesitate to produce them.”
“Produce them, Mr. Gailey. Put them here on my desk.”
“But, Your Honor…”
“Put them here on the desk. Put them here.”
Willis I admire your admirable tenacity in pursuing this matter and further checking a paper which is trying to support the cornerstone of CAGW, that rising CO2 precedes warming, and showing it to be wrong.
There is a fundamental problem with those scientists involved in climate science who believe in CAGW. They seem unable to consider anything which does not agree with what they believe and have been told to believe.
Some scientists deliberately or inadvertantly manipulate their papers accepting only ‘data’ which agrees with the hypothesis they want others to accept as a theory.
For other scientists their errors are clearly an inability to allow any alternative view to change their understanding of reality. Unless these scientists are able to consider alternative views they will not be able to accept that they might be wrong. It takes great character and determination to oppose peer pressure and begin to address ideas that run contrary to personal beliefs and in this way start to make “the intuitive leap” needed to create new ideas. Those scientists who are able to open their minds to new ideas are inevitably the ones who make new discoveries.
WUWT is the informal forum for review of papers on climate science, which because of its openess and scrupulous analysis has, for me, become far more important and reliable than journals like Nature. The decline of rigorous peer review may partly explain why statistics comparing WUWT with Nature.com show that readers of WUWT spend about twice as much time on site than do readers of Nature.
wmconnolley says:
April 8, 2012 at 12:48 am
Thank you for your visits to WUWT. Your meaningless comments and links confirms to many budding skeptics that your CAGW religion is an appalling fraud.
Do keep returning. Lest we forget.
Life, not temperature, determines the CO2 concentration, so this lead-lag discussion is pretty irrelvant.
http://oldbiosci.snu.ac.kr/includes/download.php?file=777.pdf&path=bWVtYmVy
I really don’t understand the point of this….
They cherry picked a date at the end of the ice age, when CO2 levels were at their lowest, and had no place to go but up…either that or die….CO2 levels increasing can be explained biologically, because it was limiting…..and did exactly what it should do at the time…..the second the weather gave it a break, the process started….irregardless of the weather after that
You can’t pick an extreme like this and try to compare it to not extreme…and get anything meaningful out of it
mwhite says: April 8, 2012 at 2:16 am
[Graphs showing solubility of gases in water]
“Solubility of Helium – He – in Water”
Helium seems to walk to the beat of a different drummer. Really hot, really cold and in between; it does unexpected things. I did not realize that it had this step change happening between 20-40 C in water. Weird. I wonder if anyone ever correctly predicted anything helium does. I wonder what effect its non-liner actions have on things around it.
Learned something again today. Thanks.
Now that WUWT/Eschenbach are extending temperature and CO2 records up to the present time, we appreciate the significance of the unchallenged scientific fact that CO2 levels are dominated by a huge spike in the last century.
If we take the Shakun2012 conclusion seriously, that Northern Hemisphere temperature lags CO2 concentration by about seven centuries, then we conclude that the temperature record *should* show “Hockey Stick” increases in quantities like global surface temperature, ocean temperature, and sea-level … portending global temperature rises of many degrees C and sea-level rises of tens of meters.
Thanks therefore are due to WUWT/Willis Eschenbach, for vividly and clearly, with every detail set forth, showing the entire skeptical community precisely how it comes about that the paleoclimate data support, plainly and simply, all of James Hansen’s main climate-change predictions.
>>>>>>>>>>>>>>>>>>
Summary: The paleoclimate analyses of WUWT/Willis Eschenbach and James Hansen are rapidly converging toward a consensus that AGW is real, serious, and destined to accelerate in coming decades.
Kudos therefore go to WUWT, Willis Eschenbach, and James Hansen!
Reblogged this on sciencenothotair.
Willis Eshenbach wrote:
“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 …”
This is meaningless nitpicking to cover up the fact that your previous criticisms didn’t stick. Shakun2012 did not set out to explain the evolution of temperature and CO2 during the holocene period. They were interested in the period of deglaciation.
The rise over 7900 years, until the onset of the industrial age was about 20ppM or 8% This is very small compared to the 100ppM or 45% rise that the authors were looking at during the period of deglaciation. As a forcing, an 8% change in CO2 is minscule, and other forcings such as orbital and axial forcing could be at work here.
Your comment has no bearing on the validity of the paper you are trying so hard to impugn.
Thanks Willis,
What an inconvenient fact for Shakun 2012 you have uncovered!
Congratulations!
The rise in CO2 over the last 6000 years could be associated with deforestation due to man. So, I don’t think that rise is any kind of a smoking gun. Of course, that also allows for some of the modern warming to be assicated with deforestation rather than emissions.
Once again the complexity of this subject is way above the level where we can make any reasonable assessments given the data we have. There could have been so many other factors involved which makes this entire field of study pretty much a SWAG.
I seem to be missing something. Shakun et. al imply that the ice core data is local. Don’t the O18 levels in the ice cores represent GLOBAL levels of O18? If not, just why should O18 levels be a local phenomenon?
I assume I must be wrong about O18 being global since averaging a bunch of local proxies in an attempt to overturn a global proxy would be nonsensical. Would someone please give me the ‘elevator speech’ explanation why O18 isn’t global?
Keith says:
April 8, 2012 at 3:27 am
Per the paper:
I have several problems with that procedure, which I may write about later.
w.
Keith W says:
April 8, 2012 at 3:31 am
From the paper:
It is shown as the black circles above in Figs. 1 and 2. It fits well with the NOAA source data.
w.
Dave says:
April 8, 2012 at 3:34 am
I addressed this question in a comment to my previous post, “Dr. Munchausen Explains Science By Proxy”, here’s the graphic from that comment.
w.
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
Volker,
what is the value of Pearson’s r for these two time series?
Since the plain intent of the CAGW politico-climate complex is to forge One Ring To Rule Us All, it’s very à propos.
Here’s the Shakun paper: “Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation”
http://sciences.blogs.liberation.fr/files/shakun-et-al.pdf
Eschenbach 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.”
You may believe that this threatens their argument, but the increase in CO2 was only about 8%. If the climate sensitivity were 3C, as most climate scientists believe, and CO2 were the only driver, the change in temperature at equilibrium would be about 0.3C. This is 1/10 of the average global temperature change during the period studied in Shakun2012. Accounting for this era would be the subject of another paper, and would be much more challenging given the many small forcings that need to be taken into account, and the fragmentary data.
The change in orbital forcing are in the opposite direction and are probably responsible for driving a good part of the decrease in temperature.
http://upload.wikimedia.org/wikipedia/commons/b/bf/Orbital_variation.svg
In fact this era has been well covered by others, and lack of inclusion is not a defect of the Shakun2012 paper:
http://www.meteo.psu.edu/~mann/shared/articles/Schmidtetal-QSR04.pdf
“The principle forcings are orbital, solar, volcanic and events
(such as the 8.2 kyr BP event). Land use and greenhouse gases also play a small role.”
wilt says:
April 8, 2012 at 11:42 am
No, they’re the same graphs. It’s hard to see in the abstract. But if you click on one of the graphs and then zoom in on it (in Safari it’s command – “+” on the Mac, dunno what key combo zooms in on the PC) you can see that in all cases the furthest right number on the years scale is “8”, for eight thousand years before present (1950). Then there’s one tick mark and about half a unit to the end of the graph.
All of the graphs, in other words, end at about 6,500 years before the present (BP).
w.
This is a prime example of why the internet should not be subject to political control or to control by the UN or any other international agency. The internet, among other things, provides the opportunity for scientific review and promotes discussion where there would otherwise be none.
“If the climate sensitivity were 3C, as most climate
scientistsalarmists believe…”There. Fixed it for you.
IPCC’s 3ºC model vs reality.
[blockquote]Lincoln Sparrow says:
April 8, 2012 at 9:36 am
Summary: The paleoclimate analyses of WUWT/Willis Eschenbach and James Hansen are rapidly converging toward a consensus that AGW is real, serious, and destined to accelerate in coming decades.
Kudos therefore go to WUWT, Willis Eschenbach, and James Hansen![/blockquote]
Appears “A.Physicist” is being channeled ….
[Note: “Lincoln Sparrow” is the same poster as “R Kcin” and “Marcella Twixt”. ~dbs, mod.]
Many people here misunderstand Hide the decline.
The issue had to do with more than not showing data. It had to do with actually removing data from archives.
Let’s use another example: In Fall et al Anthony and company looked at 1979 to present.
When Berkeley released a preprint that looked at 1950 to present, many people jumped all over that decision. maybe for good reason. maybe not.
The authors here set out to make a case about a particular time period. They are not hiding any data or removing it from archives ( as in hide the decline) The extra data is out there for somebody who wants to make a different case about different time periods.
The bottomline is that nothing you can find in proxies will ever be strong enough evidence to reverse known physics. GHGs increase and, all other things being equal, temperature will increase.
When you find periods where the two ( GHGs and temp) do not move in concert, you know one thing: all other things were not equal. You don’t know and you can’t know that GHGs dont increase warming. You dont and cant because fundamental physics is correct. We known that its correct because we building working devices based on that physics.
Smokey says:
April 8, 2012 at 12:23 pm
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.”
It is clear that you have zero capability of dealing with the point that I made, and neither you nor Willis Eschenbach has answered it.
“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.”
Shakun has certainly not cherry picked. He used 80 proxies covering all regions of the globe. Willis has not made that charge because he obviously knows better.
You should cut down on the number your trollish posts and do some real thinking for a change.
Jostein: Here’s the Shakun paper: “Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation”
Thank you.
Steven Mosher says:
“GHGs increase and, all other things being equal, temperature will increase.”
Allow me to restate that correctly:
Ocean temperatures increase, and all other things being equal, CO2 will increase.
Steven Mosher: GHGs increase and, all other things being equal, temperature will increase.
Ah. I see that now you add “other things being equal”. Now all you have to show is that it is possible to tell when all other things are equal, have been equal, and will be equal.
Willis, thank you very much for clarifying the question whether the graphs shown with the Abstract are different from the “real” ones in Shakun’s paper. I had zoomed in to some extent and by mistake thought (as Chris V perhaps did as well) that the furthest right number was 0 instead of 8.
So you have convinced me now that Shakun left out all the recent data from 6,500 years before the present. I am still not sure that this was done deliberately, but the authors surely would have done the decent thing by showing ALL the relevant data (and then explain why the CO2-temperature relationship would be different in recent times).
Jostein says:
April 8, 2012 at 12:48 pm
Many thanks, Jostein, I’ve added this to the head posts of this and my previous post, and given you credit.
w.
Willis graph of CO2 seems to me to be the same as the one in IPCC, AR4 chapter 6, p 448, fig 6.4. In the AR4 report we can se that the level of CO2 is increasing from about 6000 years ago.
“Man_Tran says:
April 8, 2012 at 8:36 am
As a dynamicist, I was intrigued by the ‘high frequency’ transient in some of the proxy data that has a positive peak around -12k yrs and a negative peak around -10k years. I would love to see someone correlate that with other events during that era”
The 10Be record from GISP2 ice and from the Taylor dome give the same line-shape. Of course, we all know that solar output, cosmic ray levels and Stella dust can have no impact on temperature or atmospheric CO2.
Eric Adler says:
“Shakun has certainly not cherry picked.”
Then what would you call Shakun’s carefully selected time line? A simple mistake? Read wilt’s comment above.
Willis, will you be invited to ICCC-7 ? I am one of those amature geeks that watches the heartland streaming of the event. I would love to see this as a presentation, and some of your other climate investigations.
The graphics are tiny on the abstract page – and as Willis notes people are not seeing what they actually show. Another member posted this link:
http://i39.tinypic.com/f0qkcw.jpg
Which shows – by scale at bottom – that the record is truncated at point they stop reporting CO2 appx 6500 years BP.
And Willis – it is “CTRL” and “+” (or “-“) to zoom in the PC world
Willis,
To avoid being accused by alarmists of truncation of data, modern CO2 levels and temperatures might be overlaid. I’m sure someone will do it. To make it real, other CO2 proxies should also be shown.
Steven Mosher says:
April 8, 2012 at 12:59 pm
Good to hear from you. You are correct when you say that the authors are talking about “a particular time period”. My point is that that specific time period was very carefully chosen.
Again you are 100% correct that all things being equal temperature will increase. But the climate actively adapts and responds to changes, so things are never equal. If temperatures change, cloud patterns change. Ocean currents change. Tropical cirrus forms earlier. We get more El Ninos. And the balance is maintained. The amazing stability of the planetary temperature is the result of those and dozens of other homeostatic and thermostatic mechanisms.
Look at Figure 1. The median rise shown there is about 4°C from the low point around 16,000 BC to the high point around 8,000 BC. Which means that over the last ten thousand years, the globe has cooled by around a degree. For a heat engine which throws away about 30% of the incoming energy (albedo reflections) that is governed by something as insubstantial as clouds, that is astounding stability.
Since in natural flow systems all other things are never equal, this statement doesn’t mean anything.
I see the problem. You are conflate two separate ideas. They are:
1. GHGs cause increased forcing.
2. Increased forcing causes increased warming.
The first statement is fundamental physics and is undoubtedly true.
The second statement, as you point out, is only true if other things are equal … but other things are never equal. So it is not “fundamental physics” by any stretch of the imagination.
w.
major9985 says: “Why dont you average the proxy temperature records Willis?”
Averaging data does not create information; it destroys it.
Almost all the proxies are coastal, implying milder climates compared to the interior. And of course low elevation.
Is there any difference if you just use non-coastal proxies?
Willis, you may have missed Pat Frank’s comment at April 8, 2012 at 2:38 am. Thought he made some excellent points. My own view is that Shakun’s thesis has a single thrust, which is typical of graduate theses, but NATURE should have a broader view and so their editorial policy should instill some context, but evidently they do not.
Alvin says:
April 8, 2012 at 1:15 pm
I was hoping so, but I guess my invitation must have gotten lost in the mail … I spoke at a previous conference, the 4th one. I livetooned it here and here. There was a video of my presentation somewhere on the web, I can’t find it now.
w.
Willis: “…I leave everyone to ponder how far climate “science” has fallen, that a tricksy study of this nature can be published in Nature … The only thing this study supports is the need for better peer review …” You are absolutely right. I sometimes wonder about that too when I see these tricksy studies. Nature is not the only one, though, Science is into it too. Trenberth and Fasullo published an article in Science tracing earth’s energy and mysteriously lost track of it. Everything was fine until 2004 when the energy began to leak away and by 2008 eighty percent of it was missing without a trace. They wondered about its whereabouts and asked: “If the extra energy has gone into the ocean, where has it gone?” Well, the ocean seemed to be unlikely on the face of it because they had just stated that “Since 2004, ~3000 Argo floats have provided regular temperature soundings of the upper 2000 m of the ocean, giving new confidence in the ocean heat content assessment.” Now what do you know, new equipment comes on line and energy makes a disappearing act! I don’t think this paper was ever reviewed because if it were the first thing any referee would have done is to send him back checking those buoys. The lesson is that rank has its privileges: if you are a big shot in the climate field the least you can expect is to have your paper waved past the editorial process.
The standard line is that CO2 effects were too small pre-WWII to have a significant effect on temperature, and being skeptical that marginal changes in CO2 are responsible for much temperature change post-WWII, I have no trouble accepting that, but Willis is right: for those who take the opposite view, the increasing levels of CO2 over the Holocene ought to cause warming.
Googling Law Dome CO2 images to verify Willis’ numbers, guess who pops up with the first 10,000 year image? John Cook:
http://www.skepticalscience.com/print.php?r=95
His commentary does not accord with his graph:
Every time I see a Temp/CO2 record like this it seems there is one big obvious question: “What caused temps and CO2 to stop their rapid rise and plateau appx 8000-9000 years ago?
It would seem that is the direct signature of the climate “thermostat” mechanism. Temps had been rising rapidly along with CO2 and then they abruptly stopped, and remained relatively stable with minor cooling trend since.
I found some info on the “8200 year event” – here is a note regarding some possibilities:
Whatever triggered the response was strong enough to cause a dramatic shift – from rapid rising temps and CO2 to the long, stable temp period we’ve seen since.
These graphs of the very stable temp record over the last 8000+ years – which show the recent warming the AGW side bases all their doom and gloom, sky is falling meme on – show that the recent warming is not even outside the normal variation of the last 8000+ years of stable temps.
That is what made me a sceptic. If the warming they are scare mongering about, when looked at in even a 8000-9000 year period does not even break thru the natural variability of that time period (let alone when reviewed in climate cycle time frames) then how can it be of ANY import or concern.
If one glacial to interglacial climate cycle is one climate “day” (lasting appx 115,000 years) that would make the last 8500 years equal to appx 1 3/4 hours of that one climate cycle “day” – less than 8%. How can a temp change that is within the historical natural variability range of a time period comprising less than 8% of a single typical climate cycle have any statistical relevance regarding climate change at all?
[Note: “Lincoln Sparrow” is the same poster as “R Kcin” and “Marcella Twixt”. ~dbs, mod.]
A serious question: does WUWT make a deliberate practice of selectively “leaking” posts thought to be anonymous? If so (as the above evidence indicates), then what selection criteria is WUWT presently using in making the determination to “leak” or not? And do WUWT’s readers have the right to know the WUWT’s “leak” criteria?
[Reply: Sockpuppetry violates site Policy. For example, you also post as “Frederick Davies”. ~dbs, mod.]
Question: If ~300 ppm is not high enough to stop an ice age, how high would CO2 levels have to be to stop one?
~1000 ppm…..well, no
+2000ppm……well, no again
Thanks Willis for your excellent article and ongoing explanation.
Peer review in climate science journals has once again been shown as a flawed and ‘tricksy’ process. Some of these science journals make themselves less relevant the more they publish. In contrast Anthony and contributors on WUWT have enabled instant ‘peer review’ by both unbiased and biased scientists (and a mixed audience).
It is also useful to read posts from people with ‘questionable’ views as it enables insight into their mindset, occasionally they even forward a good argument and it is not good to surround yourself with ‘yes men’ (journals take note). I am sure I’m not the only one who finds it helpful when contributors reveal relevant verifiable history about some of these people. I also find the moderators do a good job of removing nasty malicious or over the top comments (even mine).
Most of my contributions tend to be of a satirical nature, hopefully on themes and people who deserve it and if I infrequently raise a smile that is a success. Sometimes it’s good to ‘bring it down a notch’ and call on ‘Flash Gordon’ when alarmists say we only have hours to save the Earth.
Thanks Anthony, Willis and contributors.
All this and no paywall!
DocMartyn says:
April 8, 2012 at 7:33 am
“Climate sensitivity is not constrained by the last two decades of imperfect satellite data, but rather the paleoclimate record.”
NASA climatologist Gavin Schmidt
Richard Alley’s position denies Gavin’s position starting at 23:00
Alley fights to tell staff members at Penn State that scientists’ “Global Warming” is not based on the so called “broken hockey sticks”, but on the satellite record.
Willis,
The BBC journalist’s email address is at the end of the article: Jonathan.Amos-INTERNET@bbc.co.uk
…how about asking him openly and directly if he’s now going to retract or correct his article.
I am trying to understand why the graph scales do not match the perimeter of the graph.
One thing that Willis’ analysis shows is that ice core CO2 data are very poor as a proxie for global temperature as compared to the O18 index. I suggest that the actual atmospheric CO2 concentrations were considerably higher when we had higher temperatures as indicated by the O18 index. I further suggest that a more accurate estimate of pre-historic CO2 concentrations can be obtained by establishing a modern day global temperature/atmospheric CO2 relationship (not a model fudge factor) and work backwards using O18 as the temperature proxie. In so doing, we should be able to settle the lead/lag debate.
A. Scott says:
April 8, 2012 at 1:50 pm
How can a temp change that is within the historical natural variability range of a time period comprising less than 8% of a single typical climate cycle have any statistical relevance regarding climate change at all?
========================
It doesn’t……………you can’t use your brain to play this game
I leave the readers to consider the fact that for most of the Holocene, eight 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 …
———–
So what are you trying to say here Willis? That this graph proves that rises in global temperature do not cause CO2 out gassing from the oceans? Which would be proof that that this favorite climate skeptic and climate warmist argument is wrong.
That’s laudably skeptical of you Willis to follow where the data leads irrespective of whether it supports your initial position.
Any ideas why CO2 and temperature are going in opposite directions?
Lazy,
Consider that the ice core CO2 data are a poor proxie of the actual pre-historic atmospheric concentrations of CO2. We don’t really know what happens to the air bubbles under the extreme pressures of the many meters of ice.
Willis, what is the scale for CO2? And can you please put a key on the graph?
Thanks, NQ
Thanks dbs, mod.
Why do some people think it is acceptable to post under multiple names?
I wonder… : < (
Richard (hot under the collar)
Lazy says:
“Any ideas why CO2 and temperature are going in opposite directions?”
If you could ever get over your fixation on “carbon” propaganda, you might conclude that CO2 may not have the effect claimed. And of course there is also the well established CO2 lag time, which allows for divergence.
Lazy, I am trying to understand which graphs you are referring to.
Hugo M says:
April 8, 2012 at 12:36 pm
Volker Doormann said on April 8, 2012 at 11:24 am:
“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
Volker,
what is the value of Pearson’s r for these two time series?
I don’t know. I have no tool to compute the value, but maybe you can check it out from the data (links in the graph)..
My point was my general questions here to whom it concerns.
The heliocentric climate world view seems to be an anathema by the peer here, well known that the saw tooth like oscillations can easy be calculated out of the sun’s geometry and the photon diffusion time after Prof. R. Ehrlich:
http://www.volker-doormann.org/images/bentic_f_graph.jpg
It seems people more fight holding magazines clean than fighting for truth in science.
V.
Sorry, correct link is
http://www.volker-doormann.org/images/bentic_f_graph.gif
V
[Note: “Lincoln Sparrow” is the same poster as “R Kcin” and “Marcella Twixt” … “Evangeline Maergulis”, you also post as “Frederick Davies”. ~dbs, mod.]
It’s evident WUWT is working hard to identify anonymous posters … it’s less evident that WUWT is accurate in its identification attempts.
Considering that WUWT posts commonly contain personal abuse and threats against scientists (including this thread), and such threats go unchecked by WUWT moderators, perhaps maintaining anonymity is prudent … for everyone who posts here?
Certainly one can understand why the number of practicing scientists who post on WUWT is very nearly zero. That number of scientists will now diminish by one.
Comment: It’s sobering to contemplate that anonymizing networks that were conceived to protect the free speech of citizens against state tyranny and retribution, now find service in protecting the free speech of citizens against the too-high prevalence of WUWT-hosted abuse and threats.
REPLY: Oh, please.
First, We have a policy page. I don’t let certain people in my own home that abuse my trust, and my home on the Internet is no different. People that don’t wish to abide by policy get called out on and if they don’t change their behavior, end up getting banned. There have been a few. For example I banned recently a person known as Victor Barney for making hateful racist comments and comments about the intelligence of women. I suppose by your logic, you’d support him taking on a new persona to get around the ban and spew the same hate all over again?
Second, Show us “abuse and threats”. I’d really like to see those myself.
Third, People are welcome to comment on all sides of the issue, however we have limits, based on our experience and made quite clear in the WUWT policy page. For the same reason I don’t allow people in my real home to act boorishly, so it goes on my home on the Internet.
Fourth, Like any private establishment, we reserve the right to refuse service to anyone. If any of our policy bothers you, you know where the door is.
Fifth, WordPress.com our hosting service, expressly supplies the IP adresses of all commenters, not only on our blog, but on every WordPress blog in existence. When we see multiple comments from the same IP address under differ handles, it is easy to identify, we don’t go looking for it.
Sixth, Our success stands on its own. We don’t plan to change policy for a few whiners or people that like to play shape shifting games or people that think shape shifting equates to free speech.
– Anthony Watts
Several people have said that orbital forcings are the reason for the decline in temperature over the holocene. As the earth goes around the sun, over time the eccentricity and the obliquity of the orbit slowly changes.
The problem with this theory is that the orbital forcings change the distribution of the sunlight, but barely change the total sunlight at all. Since there is no change in TOA insolation, why would that cool the earth?
The prevailing hypothesis is that the change in surface temperature is equal to the climate sensitivity times the change in total TOA forcing … and over the period in question there was no change in total forcing from variations in the earth’s orbit.
Nor is it at all clear what effect the change in the distribution of the sunlight would make. Generally the changes meant warmer summers and cooler winters at high latitudes … would that warm or cool the planet?
Regards …
w.
“there must be a scientist on the author list”
What does that mean? Isn’t the work — data right, process right, math right — more important than the credentials?
These two posts of Willis’ remind me of a comment by Tom Wigley:
“Although these all show the hockey stick shape, the differences between them prior to 1850 make me very nervous. If I were on the greenhouse deniers’ side, I would be inclined to focus on the wide range of paleo results and the differences between them as an argument for dismissing them all.”
If the proxies are so over the map, can any of them be trusted to be representation of past temperatures?
Does Nature want to be aware of this? No, certainly not!
When you find periods where the two ( GHGs and temp) do not move in concert, you know one thing: all other things were not equal. You don’t know and you can’t know that GHGs don’t increase warming. You don’t and can’t because fundamental physics is correct. We known that its correct because we building working devices based on that physics.
Man has build functioning devices long before we understood how they worked. We built steam engines even as we subscribed to the phlogiston theory and had a woeful grasp of thermodynamics. We built dynamos, which worked, based on a totally wrong understanding of electricity. (Hence why positive “current” flows the wrong way compared to the actual electrons.)
Some humility about our understanding is useful at all times. And particularly so in new areas, such as climate science. My bet is that almost everything we “know” will be wrong, at least in details.
What would the warmists suggest could be a plausible possible alternative mechanism for pumping all of that extra CO2 into the atmosphere at the end of a glacial period, that continued for thousands of years?
The solubility of Carbon Dioxide in ice is about two orders of magnitude less than the solubility in water. Freeze sea water. What happens to CO2 levels?
If I take a Northern Hemisphere [pick any Northern Hemisphere you like] covered in thick glaciers and melt them rapidly into the oceans, will the atmospheric CO2 concentration go up, or will it go down?
wilt says:
April 8, 2012 at 1:07 pm
“So you have convinced me now that Shakun left out all the recent data from 6,500 years before the present. I am still not sure that this was done deliberately, but the authors surely would have done the decent thing by showing ALL the relevant data (and then explain why the CO2-temperature relationship would be different in recent times).”
The author chose to study the era that he did, and did ground breaking work in calculating the global temperature change during the end of the last ice age. This enabled him to model regional temperature change and show how CO2 drove climate change.
Shakun’s paper was an excellent achievement and earned him a doctorate. He was under no obligation to study the holocene era as well. There is no real issue of decency here, unless you believe in some kind of conspiracy theory.
As I have pointed out, using the generally accepted figure of 3C for climate sensistivity in that era, if CO2 were the only driver, the temperature increase would have been about 0.3C. In fact variations in the earth’s orbit and axis are currently causing long term cooling. Reduction in summer sunlight in the Northern Hemisphere allows more snow and ice to remain on the ground. The enhanced reflection of the sun’s rays causes cooling. Variations in solar intensity, volcanic aerosals and vegetation also affect the evolution of climate. The presence of so many small forcing factors make modeling the holocene period very complicated.
The increase in CO2, on a percentage basis, due to industrial emissions, is comparable to the 45% seen during the last deglaciation period, but the current duration for this increase is about 200 years, versus the 5000 year period that it took for the last deglaciation. So the current change in CO2 represents a comparable forcing factor to the deglaciation.
One more point about the Younger Dryas. We known the YD both began and ended rapidly, in less than 50 years and perhaps as few as 10. Looking at figure 2, the plateauing of CO2 clearly precedes the YD cool period. Are we to interpret this as, when CO2 stopped rising, the climate rapidly cooled?
Similarly, the resumed rise in CO2 occurs during the cool period.
Or more likely, it indicates a calibration issue, and the CO2 dating is too early (or the temperatures too late).
climatebeagle says:
April 8, 2012 at 3:35 pm
“If the proxies are so over the map, can any of them be trusted to be representation of past temperatures?”
Hmm… yes, and no !
yes they can be considered to be a representation of past climes (not just temperatures don’t forget) but the term representation is the crux. Do you remember the old method of drawing a big version of something using a tracing device (can’t think of the name at the minute) or vice versa – well, in my opinion, all proxy data is at one end of one of those devices – the thing is, which end? do the proxies under or over estimate? etc, etc. Why couldn’t they calibrate ice core data to ‘current’ times, for example?
Nice point, tell that to Hansen (1988) and compare to the present global mean temps. Not (yet) opposite but wrong. IPCC 1990 again wrong. Think a about it.
Ideas: Oceans, sun, inclination…………..
Steven Mosher: The authors here set out to make a case about a particular time period. They are not hiding any data or removing it from archives ( as in hide the decline) The extra data is out there for somebody who wants to make a different case about different time periods.
Shakun et al make a claim that is weakly supportable from their analyses, namely that CO2 increase preceded global temperature increase (their monte carlo test is nice, but not strong, and ignores the antecedence of the Antarctic temp rise[unless I missed it — only one read through so far.]) They made a much less supportable claim, namely that CO2 increase may have caused the global temperature increase; it is less supportable because Antarctic temperature increase preceded CO2 increase, so “global temperature increase” is just as likely to be a consequence of Antarctic temperature increase; and the causal link is further undermined by the data that Willis presented today.
The causal claim was inappropriately trumpeted in the press release, which is one of the reasons for my recommendation that Willis submit a letter to Nature. The paper is good up until it makes a causal claim, but the causal claim should surely be challenged.
And Nature used to be a reputable journal.
It has sure pissed its reputation against the wall in an effort to follow (or perhaps lead) the political stampede.
wmconnolley says:
April 8, 2012 at 12:48 am
I read your comment, wm, and came to one conclusion:
You maintain diffusion of CO2 in the forming ice likely causes a biased trend, for which you assign a value of “several hundred years” (which still isn’t enough to reverse the order of T rising before CO2, by the way).
Yet I know of no diffusion process that would produce this so-called “biased” results of which you speak. Diffusion is known to work much the same in all directions; one could argue there’s as much diffusion of CO2 downward through the solidifying snow as there is upwards.
The only caveat you attempt to establish in your link is that there is “uncertainty in the data” (your words).
Therefore what you call “wandering off in conspiracy land” is based on nothing more than “uncertainty”, yet in my opinion it is just one unsubstantiated supposition–if anybody’s pushing a conspiracy, it is you. It is you that’s trying to convince people of biased diffusion that has no little or no basis in fact. It is you that’s trying to fit natural processes to your “religion” of CAGW. And to accuse people of “wandering” yet you admit “uncertainty” is truly beyond the pale. (You must have nightmares at night about pointed refutations of papers like Shakun’s)
And for those of you supporting wm here, you’re guilty by association.
Read his link and see if you can come up with scientific proof refuting his real conspiracy–we’d all be glad to hear what you have to say.
Then come back and delve into the meat that Willis presents and you’ll see a big difference. Nobody, especially wm, should be throwing charges of “wandering” when all they’ve got as “evidence” is “uncertainty”. It does their argument no good.
Eric Adler says:
April 8, 2012 at 4:22 pm
Maybe we should work on tripling the CO2 contribution to the atmosphere, then, so the temperatures will actually go UP instead of declining.
That, or your hypothesis is incorrect.
Willis,
I agree that the cut-off date in the paper being coincident with the rise in atmospheric CO2 during the Holocene is too clever by half, and for sure not a coincidence, since it clearly weakens the “case” the paper is trying to make. But the rise in CO2 (and atmospheric methane as well) starting about 6500 years ago is something that has been widely recognized (and the cause for which debated) for quite some time. I think the most widely accepted position is a significant contribution to increases in CO2 and methane from the rise of agriculture. The continued cooling during the Holocene, in spite of rising CO2 and methane is (of course) an inconvenient fact that must be explained. I have seen several explanations offered, including increased albedo from farming offsetting the CO2/methane forcing, and shifting of the season of the Earth’s perigee, and no doubt other explanations have been offered. Are they right? Who knows… and who cares?
FWIW, my take is this and all similar studies try to draw far to much information from a noisy jumble of proxies. It is clear that Milankovitch cycles are primarily responsible for ice ages; trying to discern what are (at best) speculative secondary factors is mostly a waste of time. After all, if the IPCC claims no ability to narrow climate sensitivity to better than “2C to 4.5C” using all available instrumental data and decades of intensive study, how much credibility can one reasonably give an analysis of very noisy proxies from 10,000 years ago? IMO, it is just kind of silly drivel… climate porn, if you will. But it is too bad this kind of stuff makes its way into so many breathless reports of “confirmation of sensitivity to CO2” in newspapers all over the world.
Steven Mosher says:
April 8, 2012 at 12:59 pm
The bottomline is that nothing you can find in proxies will ever be strong enough evidence to reverse known physics. GHGs increase and, all other things being equal, temperature will increase.
=======================
We hear “all other things being equal…” a lot. So, please tell us when the last time was that all things were equal?
How about we dipense with the purely hypothetical and start addressing the real world?
Although the article’s limited time application may be all it meant to be, it is used by Nature as much more. Here is part of Nature’s lead editorial, “Bolstering the Link,” which clearly shows Nature intended Shakun to help Gore and the global warming cliques. It is internally contradictory to a comical degree, but I will not comment except I think it should repeated as a thread on WUWT titled like “Fisking the Link” for imputing things to Shakun et al. that they did not say:
“Bolstering the Link”
….
First, as Jeremy Shakun at Harvard University in Cambridge, Massachusetts, and his colleagues show on page 49, carbon dioxide does drive atmospheric warming. Uncontroversial stuff, perhaps, yet the link continues to be questioned by people who would play down the risks of human greenhouse-gas emissions. The queries re-emerged in 2006, when former US vice-president Al Gore showed a graph of historical carbon dioxide levels and temperature in his movie, An Inconvenient Truth, and was accused of glossing over the relationship between the two. So let there be no confusion now: the new study confirms that, as Earth emerged from the last ice age some 19,000 to 10,000 years ago, rising global temperatures were preceded by increased global carbon dioxide in the atmosphere — a result that emphasizes the role of carbon dioxide in driving global change in the present day. This relationship is a foundation stone of climate science and of policies to regulate greenhouse-gas emissions, and it is solid.
Quelle surprise! the climate sceptics may shout — scientists find proxy data and use a computer model to get the answer they wanted, to seal the conspiracy. Then let the second paper this week show that modern science does anything but offer self-serving results to support existing ideas. For, in a paper published online, Ben Booth and his colleagues at the Met Office Hadley Centre in Exeter, UK, use a different model to question conventional wisdom on how the climate of the North Atlantic Ocean operates (B. B. B. Booth et al. Nature http://dx.doi.org/10.1038/nature10946; 2012).
This study looks at the impact of aerosols — such as sulphur dioxide particles ejected by volcanoes and linked to the burning of coal — on sea surface temperatures there. Aerosols that reflect sunlight and can promote brighter cloud formation have been known for some time to affect climate, but the idea has gained appeal in the media during the past decade, under the tag ‘global dimming’.
The study suggests that global dimming could underlie warm and cool periods observed in the North Atlantic basin in the twentieth century — a variability known as the Atlantic Multidecadal Oscillation (AMO). And because the AMO has been implicated in global processes, such as the frequency of Atlantic hurricanes and drought in the Sahel region of Africa in the 1980s, the findings greatly extend the possible reach of human activity on global climate. Moreover, if correct, the study effectively does away with the AMO as it is currently posited, in that the multidecadal oscillation is neither truly oscillatory nor multidecadal.
The implications of this are great, both for study of the climate system and for the impact of policies to control aerosol emissions. It also shows that solid science does not have to be settled science, and that this is no bad thing.
Willis: If you intend to plot CO2 on a serious graph along with temperature, I suggest that you first take the log of the CO2 data (which should be proportional to any temperature change it may cause), then normalize. It may not make any difference, but you don’t want to look like Al Gore in An Inconvenient Truth rising on the lift to point out where the are headed (perhaps 1.5 doublings of CO2) on that infamous graph of temperature and CO2 vs time.
btw, does the repetition of “solid” mean that the Oglivy PR guys figured out a new meme, something like “It does not have to be settled science, just solid!”
The IPCC projections are based on an unacceptable 3ºC+ per 2xCO2, but those projections are falsified by the planet. So we can disregard the AR-4 hindcast/forecast models due to their failure to come anywhere near real world obsevations. Global temperatures have been flat to declining for 15 years, yet the IPCC still claims a preposterous 3ºC+ sensitivity number:
http://img811.imageshack.us/img811/4146/ar4ensemblemeanvshadcru.png
Note the flat temperatures since the late 1990’s.
Next, the ice core data clearly show that rises in CO2 follow rises in temperature:
http://theinconvenientskeptic.com/wp-content/uploads/2010/09/Vostok-CO2.png
This relationship [rises in CO2 always following rises in temperature — has remained constant for the past 400 millennia:
Past 400Kybp: http://www.ianschumacher.com/img/icecores.gif
A more detailed chart showing the same relationship:
http://www.brighton73.freeserve.co.uk/gw/paleo/400000yearslarge.gif
Another one of many charts showing that CO2 follows temperature:
http://www.appinsys.com/globalwarming/GW_Part1_PreHistoricalRecord_files/image023.gif
Shakun et al. have given the alarmist contingent a fatally flawed paper that attempted to overturn decades of data. Their paper was hand-waved through pal review, which ignored the fact that most of the inconvenient Holocene was omitted; only the small cherry-picked part that supported their conjecture was used.
However, the fact that Willis easily deconstructed Shakun’s flawed methodology means nothing to the tribalist alarmist crowd, which as usual completely ignores the scientific method — just as they ignore the central fact that a warming ocean outgases CO2, not vice-versa. CO2 is not warming the oceans; warming oceans are outgasing CO2. But try to explain that simple fact to the true believer alarmist crowd.
Smokey says:
April 8, 2012 at 6:11 pm
“However, the fact that Willis easily deconstructed Shakun’s flawed methodology means nothing to the tribalist alarmist crowd, which as usual completely ignores the scientific method — just as they ignore the central fact that a warming ocean outgases CO2, not vice-versa. CO2 is not warming the oceans; warming oceans are outgasing CO2.”
Which is easily verified in the laboratory.
Steven Mosher : April 8, 2012 at 12:59 pm
said “…The authors here set out to make a case about a particular time period. …”
No, quite clearly they set out to make a case about the relationship between temperature and CO2 levels.
Steven Mosher April 8, 2012 at 12:59 pm
said “….. all other things being equal, temperature will increase.
When you find periods where the two ( GHGs and temp) do not move in concert, you know one thing: all other things were not equal. …”
Has anyone else noticed the slow but certain acceptance by CAGW proponents that the sun, Milankovitch cycles, and other factors DO in fact play a very significant part in global temperature variation?
I don’t want to steal Willis post, but I would like to show and tell.
Here are the plots of EPICA Dome C, Deuterium temperature, -log(Dust mass), Iron and Sulphate mass, and the Taylor Dome 10Be measurements (Taylor has the best 10Be dataset).
Temp and minus Log(Dust) last 30K
http://i179.photobucket.com/albums/w318/DocMartyn/EPICADomeC10BeDustDeuteriumanddustsize.jpg
Temp and 10Be last 30K
http://i179.photobucket.com/albums/w318/DocMartyn/EPICADomeCDeuteriumand10Be.jpg
minus Log(Dust) and (inverted) 10Be last 30K
http://i179.photobucket.com/albums/w318/DocMartyn/EPICADomeCDustTaylor10Be.jpg
Iron and Sulphate
http://i179.photobucket.com/albums/w318/DocMartyn/EPICADomeCFeandSO4.jpg
RockyRoad says:
April 8, 2012 at 5:35 pm
“Eric Adler says:
April 8, 2012 at 4:22 pm
[…] So the current change in CO2 represents a comparable forcing factor to the deglaciation.
Maybe we should work on tripling the CO2 contribution to the atmosphere, then, so the temperatures will actually go UP instead of declining.
That, or your hypothesis is incorrect.”
Your ignorance of climate science is showing. You seem to be referring to the recent slowdown in global warming. It is well understood that internal variation during such a period can overcome the global warming trend due the GHG’s. In addition sulfate aerosals, which have a short lifetime in the atmosphere are believed to exert a cooling influence. This will be transitory.
Global warming due to any forcing has a built-in delay due to the vast heat capacity of the earth. With such a rapid ramp up of CO2, the increase in surface temperature will certainly be delayed by a large amount.