People send me stuff.
Tonight I got an email that contained a link to a paper that takes on the wonky claims related to barycentrism and Earth’s climate, specifically as it relates to Nicola Scafetta’s 2010 and 2012 papers. This new paper taking on the Scafetta claims will be published in the Journal of Atmospheric and Solar-Terrestrial Physics, April 2014. The author is Sverre Holm Department of Informatics, University of Oslo, Norway.
Abstract, some graphs, and discussion/conclusion, along with a link to the paper follows.
Abstract
It has recently been claimed that there is significant coherence between the spectral peaks of the global temperature series over the last 160 years and those of the speed of the solar center of mass at periods of 10-10.5, 20-21, 30 and 60-62 years. Here it is shown that these claims are based on a comparison between spectral peaks in spectral estimates that assume that the global temperature data contains time-invariant spectral lines. However, time–frequency analysis using both windowed periodograms and the maximum entropy method shows that this is not the case. An estimate of the magnitude squared coherence shows instead that under certain conditions only coherence at a period of 15-17 years can be found in the data. As this result builds on a low number of independent averages and also is unwarranted from any physical model it is doubtful whether it is significant.
…
Discussion and Conclusion
Scafetta (2010) claimed the global temperature series for the last 160 years to have
spectral lines at 21, 30 and 62 years. Time–frequency analysis shows that the lines are
time-varying (Figs. 1 and 2) and very different from the nearly constant lines in the
time–frequency plot for the speed of the center of mass of the solar system (SCMSS)
(Fig. 3).
The supposed periodicity around 30 years in Scafetta (2010) is not really
present in the climate series at all and could be an artifact due to a combination
of model overfitting and smearing due to the time-invariance assumption which has
been forced on the data. The claimed spectral peaks by Scafetta (2010) for the global
temperature series are therefore not reproducible if proper consideration is taken of
the time-varying nature of the data. The only significant coherence between the cli-
mate series and the sun’s movement that was possible to find was at 15-17 years (Table 1). However, both the low number of independent averages that it builds on as well as the lack of a physical explanation for this coherence, makes us hesitate to claim that it is significant.
===============================================================
Looks to me like “game over” for claims of Barycentrism controlling Earth’s climate. Clearly this was a case of pulling a signal from noise that is just an artifact of the process, much like Mann’s special brand of math that made hockey sticks from just about any red noise input data.
Full pre-print of the paper here: http://arxiv.org/pdf/1307.1086.pdf
dikranmarsupial says:
March 12, 2014 at 7:34 am
So your explanation for these observations is what?
Temperature
http://climatedatablog.files.wordpress.com/2014/02/hadcrut-giss-rss-and-uah-global-annual-anomalies-aligned-1979-2013-with-gaussian-low-pass-and-savitzky-golay-15-year-filters1.png
PDO
http://climatedatablog.files.wordpress.com/2014/02/pdo-reconstruction-1470-1998-shen-2006-with-gaussian-low-pass-30-and-75-year-filters-and-hadcrut-overlay.png
Co-incidence?
@-RichardLH
” The fact is that there IS a ~60 year cycle to all of the data. The fact that you cannot find the components that make it up does not mean it is not present, only that you are unable to model it correctly.”
The cycle is very difficult to find in the instrumental temperature data, falling well below the ENSO variations in magnitude. Longer proxy records do show a ~50-70 year fluctuation of varying period and amplitude. Rather like a small ENSO variation but with a much slower timescale. It probably is not a even, smooth oscillation but a chaotic fluctuation of variable period and size.
Ironically it can be duplicated in climate models and the cause of the ‘cycle’ identified as this old study shows.
http://link.springer.com/article/10.1007/s003820000075#page-1
Independent analyses of multicentury integrations of two versions of the GFDL coupled atmosphere-ocean model also show the existence of distinct multidecadal variability in the North Atlantic region which resembles the observed pattern. The model variability involves fluctuations in the intensity of the thermohaline circulation in the North Atlantic.
Martin Lewitt says:
March 12, 2014 at 6:06 am
Newtonian center of mass analysis doesn’t apply to extended bodies under general relativity
Under the weak gravitational forces in the solar system, general relativity effects are exceedingly small. Are you suggesting that the ‘Scafetta Cycles’ are general relativity effects [on par with the perihelion advance of Mercury]?
“Wonky”…that’s cold dude. Let the papers speak for themselves if they have merit. Leave the emotional dribble out of it. Watts up with that?
RichardLH, this is getting tedious, I have already pointed out that the changes in forcings plausibly explain some, but not all of the apparent cycles in the data, I rather doubt the evidence for cycles in what remains is statistically significant, but I have an open mind. Of course ocean circulation is likely to be another component as the affect the reidstribution of heat in the system. The point is that the evidence for the existence of cycles is grossly overstated when it is derived without first controlling for known changes in the forcings for which good physical mechanisms are well understood. This is not rocket science, statisticians have known about omitted variable bias for many decades.
Hi Anthony,
I read the paper. I do not understand some of the data analysis methods argued in sections 2.2, 2.3, and 2.4.
1) “The purpose of this paper is to reanalyze the data for coherence. The main tools are time–frequency spectral analysis and the magnitude squared coherence.”
——
I cannot comment on whether these tools are the definitive mechanisms to appropriately resolve coherence. Why would they be? See below.
——
2) “The estimator finds relationships between data based on linear systems theory where the effect,
y(t), is a filtered version of the cause,x(t), with noise added. The smaller the contribution of the noise at a particular frequency, the closer the MSC will be to 1. If on the other hand there is a chaotic system coupling between input and output, the MSC will not be able to discriminate be-
tween that and additive noise. In such cases it is not so useful. However, there is nothing in Scafetta (2010) that indicates chaotic coupling, so the MSC should be an appropriate measure to use.”
——
I think Holm thinks MSC appropriate because Scafetta, in effect, did not exclude it. But why would he and why then would apply a method that yields a mask? Seems like Holm is sort of exploiting a gap so to speak. ie, Scafetta did say NOT to use this eraser. So I can use it.
——
3) “However, both the low number of independent averages [a] that it builds on as well
as the lack of a physical explanation for this coherence[b], makes us hesitate to claim that
it is significant.”
——
a) the method Holm uses achieves the reduction of averages so ok. but,
b) Scaffetta is not obligated to explain why a coherence is there.
——
So, IMO (largely influenced by ignorance) this is not a death blow, rather, a good showpiece for a deathblow that is selectively lethal.
I still have an open mind. Gravity seems to be sensitive enough to have worked it out so that Bary-centrism is observable to the eye, so it seems to me that if my eye can see it, why can’t the climate system? Where would time-varying gravitational signals be amplified on earth and cast into a record?
REPLY: We can also see comets and asteroids pass by that have a small gravitational effect, does that mean they also affect Earth’s climate? I think not. – Anthony
I could almost congratulate the Holm author of this article on finding a method of data presentation turning history into a grand mess (e.g. figure 2 and the others in his paper). Perhaps he could switch to daily sampling and a scatterplot to further aid maximizing mess, or to per-second weather data (if it was available) to add extra noise.
Why plot those spectrographs alone and never, ever, ever show the data more directly like the bottom section of http://www.appinsys.com/globalwarming/SixtyYearCycle.htm ?
The second to last graph there for the sun versus the center of mass is far from a full match to solar activity history, implying what is depicted couldn’t be the sum total of all going on (at most superimposed on other factors), but at least the originators don’t have to carefully avoid letting readers see the data in a conventional plot.
I don’t agree with everything Scafetta says, but, if someone could be judged by the enemies they make, his opponents would be practically a favorable recommendation. Some things should be red flags. Extra favoring GIGO computer models precisely because of superficial impressiveness and how nobody else is likely to spend vast hours checking all the code and input datasets, while not even providing them anyway, is one red flag familar in climatology. Resorting unnecessarily and deliberately to solely relatively opaque, messy methods of data presentation (while doing a poor job pretending to be unbiased even in writing style) is another.
When a methodology or method of presentation is applied to give a conclusion, the first step is to check the implicit assumptions in it, to check the methodology itself, whether the methodology would give accurate conclusions if used on other data. This reminds me of the example I did (about 1/5th of the way down within usual illustrations on a different topic, http://img213.imagevenue.com/img.php?image=62356_expanded_overview3_122_1094lo.jpg ) of how, with plotting data at a scale with a scale monthly or more frequent to maximize noise, while applying an opaque computer model or surplus statistical processing to impress the target audience, one can “prove” “no relationship” on almost anything.
This Holm article is supposed to be a “death blow”? To even start to make a conclusion like that, do what it didn’t do: Upload all data (including the SCMSS history before it is processed into a Holm figure 3 style mess) in a convenient manner, not something taking long enough to dig up and verify that the author knows perfectly well that next to nobody is really likely to do so. Abusing the inconvenience factor is something else I watch out for in general; the infamous Doran and Zimmerman 97% consensus BS was quite successfully propagated by the simple measure of how the number of readers who would look up the specific questions asked was a small minority compared to the number hearing the 97% consensus claim in a media article not even providing a direct clickable link to the paper, and that was a far lesser barrier than applicable here.
For that matter, where would the moon’s effect be cast into a historical record on earth? Is that observable?
dikranmarsupial says:
March 12, 2014 at 7:59 am
“I rather doubt the evidence for cycles in what remains is statistically significant, but I have an open mind.”
Well there can hardly be a statistical significance to a filter! Other than the inaccuracies that produce the figures it relies on and, to some extend the leak of higher frequencies through to the pass band.
So what is your explanation for the ~60 year wriggle that IS present?
My last comment on this: I would like Holm to use the same data analysis method to show that the moon yields no effect (re:coherence) on the temperature record. The moon, the thing that raises the water level in the Bay of Fundy 50 feet twice a day. Apparently, the moon doesn’t influence climate either. Well, in that case, neither do people.
izen says:
March 12, 2014 at 7:46 am
“The cycle is very difficult to find in the instrumental temperature data, falling well below the ENSO variations in magnitude. Longer proxy records do show a ~50-70 year fluctuation of varying period and amplitude.”
So this wriggle does not exist?
http://climatedatablog.files.wordpress.com/2014/02/hadcrut-giss-rss-and-uah-global-annual-anomalies-aligned-1979-2013-with-gaussian-low-pass-and-savitzky-golay-15-year-filters1.png
RichardLH sorry life is to short to indulge those who ignore the answers to questions if they don’t like them and merely ask the question again.
dikranmarsupial says:
March 12, 2014 at 8:28 am
As you consistently do. I accept that the world is very difficult to model. I do expect the models to conform to the observations though. Just because the models cannot explain the observations does not make the observations wrong, only the models.
A significant influence of the Sun seen from cycles of the solar magnetic field, and its apparent sharp decline from the 23 cycle. The trend is downward. Magnetic activity will be manifest itself in the stratosphere over the magnetic poles in the form of blocking polar vortex.
http://www.swpc.noaa.gov/SolarCycle/Ap.gif
Dr. Svalgaard, No, I’m not convinced by Scaffeta’s results either, the ball appears to be back in his court. I just counter certain categorical arguments that are misunderstandings of the physics. Basically, “Gee, the lack of humility before nature that’s being displayed here, uh… staggers me.” (Jurassic Park movie) Any solar system effects on our climate short of Milankovitch cycles would probably have to be modulated through variations in solar activity. I’ve believe there has been a paper arguing that any regular cycles in solar activity beyond the Hale cycle would require external forcing and I don’t see any mechanism other than the gravitational or magnetic interaction of the planets. All the candidate effects seem pretty small, whether Newtonian or GR. As surprising as these this coupling would be, I don’t know of any alternate hypotheses that would be less surprising.
@- RichardLH
“So this wriggle does not exist?”
-link to graph-
of course the wriggle exists, as does the overall trend and the short term variations.
But that ‘wiggle’ is entierly insufficient in defining a cycle with a fixed period and amplitude. A cyclic variation is not detectable from less than two full periods of a putative oscillation.
Just to make my point, RichardLH wrote “As you consistently do.” which is the sort of tiresome schoolboy retort that most of us eventually grow out of. Trying to deflect the discussion onto the models is just a transparent attempt at evasion. Criticising the models (while providing no evidence) does not change the fact that assessing the presence and strength of cycles in the observations should involve controlling for the effects of known factors such as changes in forcings (to avoid omitted variable bias). It is fairly obvious why RichardLH is unwilling to accept this simple element of good statistical practice.
Anthony seems to think I am endorsing the planetary-solar-Earth climate link. But I have been careful not to do that, for the absence of an explainable cause (other than in chaos theory) makes the hypothesis very difficult to verify.
Equally, I do not necessarily endorse some of the arguments against the theory that the planets influence the Sun and the Sun in turn influences the climate. But I do agree with Anthony that there has been some incivility on the part of one or two of the advocates of the theory, and that that has not been helpful.
Perhaps Dr. Holm would be able to help me with the following questions: and I say again that I raise these questions not because I want to make a point but because I am interested in the answers. In the words of Housman’s Greek chorus: “I only ask because I want to know.”
First, there is no 60-year oscillation in Dr. Holm’s fig. 3. Yet, astronomically speaking, an oscillation of 60 years or there by has been well attested to since ancient times (though I cannot say whether it is in phase with, or in any way causatively associated with, the 60-year cycle in the ocean oscillations).
Secondly, planetary-beat models such as that of Dr. Scafetta are based on tides, in particular the 12-year Jupiter tide beat with the 10-year Jupiter-Saturn spring tide with 61-year oscillations. This oscillation has been detected in solar and consequently in aurora records by numerous authors since the 19th century. Admittedly, the period of reliable data is short, and one bears in mind the possibility of an error akin to that which was perpetrated by the peddlers of the “biorhythms” scam 20 years ago. Take three mutually prime cycles and one can draw all manner of interesting but nonsensical conclusions.
Thirdly, it is possible to calibrate a planetary-beat climate model against a reference period such as 1890-1950 and then to predict the patterns in 1950-2010 with respectable precision, and vice versa. On the other hand, this kind of backcasting is what the general-circulation models do so well, whereas they fall down when it comes to forecasting.
Perhaps the fairest test would be to continue to watch the evolution of observed, measured global temperature change against the temperature change predicted by the GCMs on the one hand and by a planetary-beat model on the other. This method has the defect that both types of model may be inadequate: but it is not unreasonable to imagine the possibility that the planetary-beat model may prove less inadequate than the GCMs.
Fourthly, it is not clear to me that analysis of a single window only 60 years wide is sufficient to distinguish beats clearly enough. Dr. Holm’s variable patterns are simple beats.
I should be interested to hear Dr. Holm’s comments on these respectfully-presented points.
@- Paul Westhaver
“For that matter, where would the moon’s effect be cast into a historical record on earth? Is that observable?”
Barely, perhaps.
there is a hypothesis that the 18.6 year lunar nodal tide cycle may increase the vertical mixing of sea surface warmth but the effect seems very small.
There is little evidence for any other lunar effect on climate, or even on the weather!
http://www.pnas.org/content/94/16/8321.short
Anthony, read my papers. Do not believe everything just for bias.
There are numerous persons that tried to rebut my papers and they were always found to have made serious errors in one way or in another.
Do you remember the cases of Benestad, Rypdal etc? Holm seems to be connected to these people, at least with Rypdal (father and son).
Moreover Holm is from the Department of Informatics, (no expertise in physics, nor in astronomy, nor in mathematics)!
He could not find a 60-year oscillation in the astronomical records despite this oscillation has been known since ancient times! See here
http://www.bibliotecapleyades.net/universo/siriusmystery/siriusmystery_appendix03.htm
And my models are based on tides not on “barycentrism”, which however is important too from the electromagnetic point of view.
Think about it.
REPLY: I have thought about it over months and years, and I’ve decided that since you refuse to show code and data, but continue your all purpose dodge mantra of “read my papers”, your work has no merit. It isn’t reproducible by anyone but you, and that makes it falsified. See Mosher’s response below. I await the predictable bluster of ego.
I suggest you respond to Holm directly, or are you afraid he has a point you can’t counter?
– Anthony
well they had a theory about a connection.. this guy tested it. No connection. theory false.
if only science were as automatic as Feynman thought or Popper thought. If only there were some rule that forced people to change their minds, their theories, their words… sorry
Now ,watch tallbloke and others : attack the method, attack the data, attack the author, attack Anthony.. In short they will do EVERYTHING BUT ‘question their theory”.
Of course there might be a way to save the theory.. some jiggery here, some jiggery there, new data, old data re jiggered, re jiggered data re re jiggered. New methods with no code provided..
plenty of ways.
In the end you either have to re do all the work yourself– or trust someone else… some paper, some post, some words ..some figures.
I’ve tried to re do scaffettas work. gavin has tried. McIntyre has tried. We all failed. We asked for code. he said no. who you gunna trust? Me? Leif. Why? its simple. He shows his work, he shares his data. When I check it I get the same answers. Is Trusting Leif an appeal to authority? No, its practical experience at work.
Building science is like building a house. You work on a foundation poured by other folks. After a while you come to understand who pours a good foundation.
Now of course some folks will continue to build a house on scafettas quicksand foundation. You cant stop them. All you can do is ignore them or laugh
RichardLH
Blimey just popped back after a while and I see you’ve got your horns locked in another battle.
This has to be one of the most contentious/acrimonious posting I’ve read on WUWT.
Right because variations and cycles in the overriding source of heat for the planet along with being a major influencer of electromagnetic activity has no or little effect on climate.
Even a layperson can see denying the sun as a major factor is nonsense.
Really, it’s no wonder some accuse Anthony of being controlled opposition ready to drive the debate step by step in favour of the alarmists.
Piers Corbyn certainly seems to get it right the vast majority of the time despite erroneous smear attempts.
Since there is no global temperature, the point is kind of moot. Or, maybe useless is the better word.
There’s a visually obvious bias in the estimates caused by using a support span that’s too narrow. It’s a trivial exercise to correct this bias.