Shock, awe. Untruncated and unspliced data used in a new paper from Briffa and Melvin at UEA restores the Medieval Warm Period while at the same time disappears Mann’s hockey stick. Here’s figure 5 that tells the story:
Look at graph 5c, and you’ll see 20th century warmth matches peaks either side of the year 1000, and that for the TRW chronology 20th century warmth is less than the spike around 1750. This puts 20th century (up to 2006 actually) warmth in the category of just another blip. There’s no obvious hockey stick, and the MWP returns, though approximately equal to 20th century warmth rather than being warmer.
Whoo boy, I suspect this paper will be called in the Mann -vs- Steyn trial (if it ever makes it that far; the judge may throw it out because the legal pleading makes a false claim by Mann). What is most curious here is that it was Briffa (in the Climategate emails) who was arguing that some claims about his post 1960 MXD series data as used in other papers might not be valid. It set the stage for “Mikes Nature trick” and “hide the decline“. Steve McIntyre wrote about it all the way back in 2005:
A Strange Truncation of the Briffa MXD Series
Post-1960 values of the Briffa MXD series are deleted from the IPCC TAR multiproxy spaghetti graph. These values trend downward in the original citation (Briffa [2000], see Figure 5), where post-1960 values are shown. The effect of deleting the post-1960 values of the Briffa MXD series is to make the reconstructions more “similar”. The truncation is not documented in IPCC TAR.
I have to wonder if this is some sort of attempt to “come clean” on the issue. Mann must be furious at the timing. There’s no hint of a hockey stick, and no need to splice on the instrumental surface temperature record or play “hide the decline” tricks with this data.
Bishop Hill writes:
Well, well, well.
In its previous incarnation, without a MWP, the series was used in:
- MBH98
- MBH99
- Rutherford et al 05
- Jones 98
- Crowley 00
- Briffa 00
- Esper 02
- Mann, Jones 03
- Moberg
- Osborn, Briffa 06
- D’Arrigo et al 06
It rather puts all that previous work in perspective, since this new paper has identified and corrected the biases. It should be noted though that tree ring paleoclimatology is an inexact science, and as we’ve seen, even a single tree can go a long way to distorting the output. On the plus side, it is good to see that this paper defines and corrects biases present in the MXD and TRW series of the Tornetraesk tree ring chronology dataset. This is a positive step forward. I suspect there will be a flurry of papers trying to counter this to save Mann’s Hockey Stick.
From the journal Holocene:
Potential bias in ‘updating’ tree-ring chronologies using regional curve standardisation: Re-processing 1500 years of Torneträsk density and ring-width data
Thomas M Melvin University of East Anglia, UK
Håkan Grudd Department of Physical Geography and Quaternary Geology, Stockholm University, Sweden
Keith R Briffa University of East Anglia, UK
Abstract
We describe the analysis of existing and new maximum-latewood-density (MXD) and tree-ring width (TRW) data from the Torneträsk region of northern Sweden and the construction of 1500 year chronologies. Some previous work found that MXD and TRW chronologies from Torneträsk were inconsistent over the most recent 200 years, even though they both reflect predominantly summer temperature influences on tree growth. We show that this was partly a result of systematic bias in MXD data measurements and partly a result of inhomogeneous sample selection from living trees (modern sample bias). We use refinements of the simple Regional Curve Standardisation (RCS) method of chronology construction to identify and mitigate these biases. The new MXD and TRW chronologies now present a largely consistent picture of long-timescale changes in past summer temperature in this region over their full length, indicating similar levels of summer warmth in the medieval period (MWP, c. CE 900–1100) and the latter half of the 20th century. Future work involving the updating of MXD chronologies using differently sourced measurements may require similar analysis and appropriate adjustment to that described here to make the data suitable for the production of un-biased RCS chronologies. The use of ‘growth-rate’ based multiple RCS curves is recommended to identify and mitigate the problem of ‘modern sample bias’.
Here’s the money quote from the paper:
If the good fit between these tree-growth and temperature data is reflected at the longer timescales indicated by the smoothed chronologies (Figures 5c and S20d, available online), we can infer the existence of generally warm summers in the 10th and 11th centuries, similar to the level of those in the 20th century.
Conclusions
• The RCS method generates long-timescale variance from
the absolute values of measurements but it is important to
test that data from different sources are compatible in
order to avoid systematic bias in chronologies.
• It was found in the Torneträsk region of Sweden that there were systematic differences in the density measurements from different analytical procedures and laboratory conditions and that an RCS chronology created from a simple combination of these MXD data contained systematic bias.
• Both the known systematic variation of measurement values (both TRW and MXD) by ring age and the varying effect of common forcing on tree growth over time must
be taken into account when assessing the need to adjust subpopulations of tree-growth measurements for use with RCS.
• It was necessary to rescale the ‘update’ density measurements from Torneträsk to match the earlier measurements over their common period, after accounting for ring-age decay, in order to remove this systematic bias.
• The use of two RCS curves, separately processing fastand slow-growing trees, has reduced the effect of modern sample bias which appears to have produced some artificial inflation of chronology values in the late 20th century in previously published Torneträsk TRW chronologies.
• A ‘signal-free’ implementation of a multiple RCS approach to remove the tree age-related trends, while retaining trends associated with climate, has produced
new 1500-year long MXD and TRW chronologies which show similar evidence of long-timescale changes over
their full length.
• The new chronologies presented here provide mutually consistent evidence, contradicting a previously published conclusion (Grudd, 2008), that medieval summers (between 900 and 1100 ce) were much warmer than those
in the 20th century.
• The method described here to test for and remove systematic bias from RCS chronologies is recommended for further studies where it is necessary to identify and mitigate systematic bias in RCS chronologies composed of nonhomogeneous samples.
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Nicola Scafetta says:
October 29, 2012 at 7:55 am
“Bart apparently took the idea from Leif’s comments and figures that were taken from my paper.”
No. I independently estimated a power spectral density of the sun spot numbers for myself, and recognized that the four peaks were the result of two peaks being rectified in the measurement. I did do so after Leif challenged me to demonstrate coherence in the data. I was pleased later to find that you and Vukcevic had also previously divined a similar relationship. It is not so obscure, indeed the relationship is readily evident, that multiple researchers would not independently recognize it.
I do not believe that planetary phenomena are behind the cycles. That is merely my opinion, but A) I do not see a plausible mechanism B) it does not explain, for me, the random phase and amplitude variation in the components C) there are so many astronomical frequencies to choose from that being able to find a few which approximately match observations is not exceedingly unlikely, and no more dispositive than the Texas Sharpshooter fallacy. You may be able to match results over the short term with such a model, but I believe that over time, it will tend to drift off.
I believe that these are merely natural modes of the Sun, which are lightly damped and have effectively random driving forces. Modal decompositions of systems governed by partial differential equations on a bounded domain are old hat. Finite Element Analysis is standard in industry for determining the normal modes of such a system.
BTW, Roger – I did not use a “maximum entropy” spectral estimator. It is the FFT of a windowed autocorrelation estimate. Leif’s direct FFT of the SSN is a different, and markedly inferior, animal. There is a lot more to using the FFT to estimate a power spectral density than simply pushing the data through an FFT.
Jan Perlw1tz;
over a time scale of about 20 years and longer
>>>>>>>>>>>>>>>
Phil Jones: 15 years
Ben Santer: 17 years
JanP: 20 years
Seems to be a trend here….
Jan Perlw1tz;
A climate scientist is a scientist who does research and publishes in scientific journals on past, present, and future climate of Earth, as a whole or aspects of it. There isn’t a big problem to define what a climate scientist is.
>>>>>>>>>>>>>>>>>
What’s your point? Using the paper which this thread is the subject of, could you please explain why it is beyond the capabilities of someone outside of climate science to read, understand, and comment fairly upon?
Leif Svalgaard says: October 29, 2012 at 8:43 am
Leif, you continue to mislead people. Vuk’s ‘sunspot formula does not have anything to do with my model. It appears similar to you, but it is not. Vuk’s ‘sunspot formula is based on double cycle length. You are not able to understand it, don’t you?
See well the periods in the formula. It uses two harmonics at 19.859 yr and 2*11.862=23.724 yr.
I use three harmonics at 9.3, 10.87 and 11.86 yr. Not two.
The ABS function used by Vuk creates half harmonics and a third harmonic in the middle, but that is not mine 10.87 yr harmonic which has a different origin.
Moreover, Vuk’s ‘sunspot formula is very regular, while mine produces a far more complex patterns. For example Vuk’s ‘sunspot formula does not get the 61 yr cycle and the millennial cycle, which my formula gets.
In your report You have used Vuk’s ‘sunspot formula (without referring to Vuk, by the way) and misunderstood it. In your review you did a mess, Leif. Let us see if you are honest enough to acknowledge it.
Bart says: October 29, 2012 at 8:49 am
Ok Bart, you found something independently.
however, about the other issues you need to read carefully my two papers
Scafetta N., 2012. Multi-scale harmonic model for solar and climate cyclical variation throughout the Holocene based on Jupiter-Saturn tidal frequencies plus the 11-year solar dynamo cycle. Journal of Atmospheric and Solar-Terrestrial Physics 80, 296-311.
http://www.sciencedirect.com/science/article/pii/S1364682612000648
Scafetta N., 2012. Does the Sun work as a nuclear fusion amplifier of planetary tidal forcing? A proposal for a physical mechanism based on the mass-luminosity relation. Journal of Atmospheric and Solar-Terrestrial Physics 81-82, 27-40.
http://www.sciencedirect.com/science/article/pii/S1364682612001034
see my web-site
davidmhoffer wrote in
http://wattsupwiththat.com/2012/10/28/manns-hockey-stick-disappears-and-crus-briffa-helps-make-the-mwp-live-again-by-pointing-out-bias-in-ther-data/#comment-1127554
With what exact statements by Jones and Santer are you comparing my statement? Please provide proof of source for the statements of the two, not just assertions from the “skeptic” rumour kitchen.
I say about 20 years, since this has been pretty consistent since the 1970ies. I consider it as very likely that the 20 year trends will still be statistically significant also in three, five or ten years from now, unless there is some strong volcanic explosion that blows a lot of reflecting aerosols in the stratosphere causing a temporary temperature dip, or some other cause the effect of which is explainable within the framework of current knowledge about the climate system, but as event not really predictable.
Perlw1tz:
No! You will NOT manage to derail this thread by flaming me into going over all your misbehaviour on the earlier thread.
Near the end of that thread Sean stated the matter much more politely than I could so I copy his post below.
And this is my last response to you on this thread. Anyway I lack time to correspond with you because I need to do the more pleasant – and more useful – occupation of removing something nasty from the instep of my shoe.
Richard
*****************
Sean says:
October 28, 2012 at 3:16 pm
Jan P Perlw1tz says: I am a troll.
Readers respond: go away troll, you have your own site to bash WUWT and post egregious l1es on, it is not our fault that you have no traffic…
Anthony Watts says: lay off the troll.
Readers wonder: when Jan was born, how many time did the doctor drop him on his head?
Nicola Scafetta says:
October 29, 2012 at 9:35 am
See well the periods in the formula. It uses two harmonics at 19.859 yr and 2*11.862=23.724 yr. I use three harmonics at 9.3, 10.87 and 11.86 yr. Not two.
You trash around. In my 2009 analysis of Vuk’s [two-period] sunspot formula, I pointed out that its power spectrum has three peaks at 9.94, 10.78, and 11.91 years [slide 2]. BTW, your 9.3 should perhaps be 9.99. To remind you, here is my first review of one of your papers: http://www.leif.org/research/Scafetta-Report.pdf
Moreover, Vuk’s ‘sunspot formula is very regular, while mine produces a far more complex patterns. For example Vuk’s ‘sunspot formula does not get the 61 yr cycle
It most certainly does: slide 8 of http://www.leif.org/research/AGU%20Fall%202011%20SH34B-08.pdf [it is simply a harmonic of the 120-yr modulation] or the table on page 1 of my review.
In your review you did a mess, Leif.
In my review I simply showed that the, by now, well-known three peaks [first pointed out by me in 2009] follow from the 120-yr amplitude modulation of the 11-yr cycle [regardless of Vuk’s formula, which I only used as illustration, having already done the analysis back in 2009]. I wonder if you will ever admit that you got the three-peak idea from me.
Jan Perlw1tz;
With what exact statements by Jones and Santer are you comparing my statement? Please provide proof of source for the statements of the two, not just assertions from the “skeptic” rumour kitchen.
>>>>>>>>>>>>>>>
These comments are common knowledge and have been discussed at length here and in other forums on both sides of the debate.
There are those who envision a transcendent reality (a “gestalt”) that they fantasize could become the actual reality if only certain aspects of our current “actual” reality could be eliminated. Not being equipped with the means of successfully dealing with actually reality, they attempt to materialize the gestalt reality which is often some chimera of Marxism or religious or environmental extremism. And since science is concerned with actual reality, it acts to hinder their desired course of events, hence “post-normal science,” which supposedly can support the desired transformation, but actually degrades our ability to deal with actual reality which is the reality that includes famine, disease, and war.
davidmhoffer says:
October 29, 2012 at 9:05 am
Jan Perlw1tz;
over a time scale of about 20 years and longer
>>>>>>>>>>>>>>>
Phil Jones: 15 years
Ben Santer: 17 years
JanP: 20 years
Seems to be a trend here….
Dead on David. The longer their “pause” continues the longer becomes their cherry picker. They will be saying that 50yrs is too short unless Hansen et al can bend the figures even more than the 3°C they have already achieved.
Piss off Perlwitz.
Leif Svalgaard says: October 29, 2012 at 10:06 am
Your review, that you have published clearly confirms what I said above.
“Vuk’s ‘sunspot formula is based on double cycle length. You are not able to understand it, don’t you? See well the periods in the formula. It uses two harmonics at 19.859 yr and 2*11.862=23.724 yr. I use three harmonics at 9.3, 10.87 and 11.86 yr. Not two. The ABS function used by Vuk creates half harmonics and a third harmonic in the middle, but that is not mine 10.87 yr harmonic which has a different origin. Moreover, Vuk’s ‘sunspot formula is very regular, while mine produces a far more complex patterns. For example Vuk’s ‘sunspot formula does not get the 61 yr cycle and the millennial cycle, which my formula gets. In your report You have used Vuk’s ‘sunspot formula (without referring to Vuk, by the way) and misunderstood it. In your review you did a mess, Leif. Let us see if you are honest enough to acknowledge it.”
See Leif, your dishonesty or incompetency is demonstrated by the fact that in your own power spectrum analysis of the sunspot record you found the three peaks that I found in my paper.
If you had repeated the analysis and not found the three peaks, you could correctly argue that you repeated the analysis, did not find the three peaks I was talking about and the paper could not be published.
But what you did was to find my same spectral peaks, and then you said that my paper could not be published. This is dishonesty or incompetency.
D Boehm says:
Since noone is disputing if the MWP was global or not, that’s not particularly relevant. What is being disputed is whether or not the warm periods in different locations were synchronous or not. If they were synchronous, then you could get a hemispherical warmth similar to the modern warmth; however, if they were not synchronous, then when you add them all together, you get a broad, diffuse bump that is less warm than the late 20th century.
And, as I pointed out, simply looking at the various charts there indeed shows that the warm periods in different regions were not well-synchronized with each other.
Jimbo says:
See above. One of the primary examples of poor argumentation is when you create a “strawman” argument of the opposing position. That is exactly what you have done with the issue of the MWP. Hence, all these wonderful papers that CO2science has found are completely irrelevant because the don’t address the actual argument that Mann et al. have made for the MWP warmth being less than the current warmth (on hemispheric or global scales). Instead, they address a “strawman” argument that the MWP was not a global phenomenon.
And, in fact, the data shown at CO2science provide evidence for exactly the reason why the current warmth ends up being less extreme than the modern warmth: For the modern warmth, the warming of different regions is largely in synch. During the MWP, the warming was not generally in-synch: Over the 500 year period from 900 to 1400, lots of regions showed some times when there was significant warmth but the times of significant warmth were often different from region to region.
davidmhoffer :
At October 29, 2012 at 9:05 am you say
I disagree about a “trend”. It is consistent.
Each stated period was longer than the time since global warming stopped.
And each period is a demonstration of desperation at the failure of the world to agree with the warmunist world view.
Assuming the AGW-scare is not history by then, if 20 years is reached then anticipate the stated period to be 30 years.
The wheels are coming off the scare. They were loosened by climategate1 and later 2. The bandwagon ground to a halt at Copenhagen in 2009. Governments are abandoning responses to the scare so, for example, ‘renewables’ manufacturers are going out of business and ‘Carbon Trading Exchanges’ are collapsing. And the MSM is starting to notice that global warming stopped 16 years ago; the Daily Mail has published about it, and the BBC is to broadcast a radio program on effects of climategate although the BBC did not report climategate 1 or 2 when they happened.
But many so-called scientists have built careers and reputations by riding the bandwagon. The panic is showing among some. Mann has become insanely litigious. Gleick has turned to deception and data theft. Another makes ridiculous attacks on WUWT threads. etc
No, your numbers are not a trend. They are some of the shouts of desperation by those on the bandwagon who are trying to make it move again when they don’t have any way to re-attach its wheels.
Richard
davidmhoffer wrote in
http://wattsupwiththat.com/2012/10/28/manns-hockey-stick-disappears-and-crus-briffa-helps-make-the-mwp-live-again-by-pointing-out-bias-in-ther-data/#comment-1127647
I see. You use the fait-accompli fallacy as pretext to chicken out of backing up your innuendo with something that has actual substance.
Leif: ““A thief thinks everybody steals””
I don’t cut the top off of my graphs to hide information.
Take a look at graph (b) MXD Chronology. The highest peak since 1700 is one third of the way into the 1900s.
Hiding information is what climate scientists do. They get caught over and over and shamelessly tell the same lies over and over.
Back in the 1880s, Wolf calculated the solar cycle period to be 11.295 years based on the 10 cycles he had reconstructed. There is an amusing numerological coincidence pointed out at the time by Charles Harrison: if you insert the periods p, masses m, and distances from the Sun d for the eight planets in the formula P = sum(p*m/d^2)/sum(m/d^2) you also get 11.295 years. Unfortunately the formula fails for the last ~100 years where the solar cycle period has averaged 10.6 years [In my report I point out the change from 11.3 to 10.6].
One can use Kepler’s third law to eliminate either p or d from Harrison’s formula, to make it [d in AU and p in years to get units right]:
P = sum(m/d^(1/2))/sum(m/d^(4/2)) or P = sum(m/p^(1/3))/sum(m/p^(4/3))
One can go one step further:
P = sum(A)/sum(A/p) where A is the angular momentum
One last trick. It can be written 1/P = sum(A/p)/sum(A) or F = sum(A*f)/sum(A) or
frequency of cycle = angular momentum weigthed average frequency of the planets
Numerology is fun!
Nicola Scafetta says:
October 29, 2012 at 10:38 am
See Leif, your dishonesty or incompetency is demonstrated by the fact that in your own power spectrum analysis of the sunspot record you found the three peaks that I found in my paper.
I found the three peaks [and the 61-yr peak] long time before you did and showed that they were simply a consequence of the 120-yr modulation of the 11-yr cycle and did not require any planetary influence. Perhaps you picked the three-peaks idea up from me without attribution.
This is dishonesty or incompetency.
As I recall, I was the third referee called in because the first two had rejected your paper strongly and the editor wanted an additional independent and unbiased opinion. You might show us the reviews by these other referees.
sunshinehours1 says:
October 29, 2012 at 10:55 am
I don’t cut the top off of my graphs to hide information
I don’t think they were trying to hide anything [especially not trying to hide the high 2003 peak], but simply used the same scale as in Figures a), b) and c). From c) it is evident that the peak in the 2000s was higher than in the 1930s. As weather is not climate, the value in any given year [e.g. that 2003 was the warmest – or was that 2011?] is not representative of climate and has no particular climate significance.
davidmhoffer:
I know it is difficult, but please try to avoid being baited by the troll.
He is evading your point by claiming he has not heard of the common knowledge which you mention. Upthread he evaded an issue by claiming he is ignorant of the Wegman and North Reports.
The only abilities he has ever demonstrated on WUWT are an inability to answer direct questions and a willingness to claim ignorance as a method to evade questions. Oh, and of course his willingness to hide his l1es behind false accusations of l1es.
He is not worth the bother of somebody such as yourself.
Richard
That’s interesting Leif!
Leif: “I don’t think they were trying to hide anything”
I do.
Leif: “From c) it is evident that the peak in the 2000s was higher than in the 1930s.”
Get your eyes checked.
perlw1tz;
I see. You use the fait-accompli fallacy as pretext to chicken out of backing up your innuendo with something that has actual substance.
>>>>>>>>>>>>>>
No it means that I’m not going to waste my time grubbing up links to quotes that are well known.
You never answered my question about winters with little or no snow being associated with late spring. Nor did you answer my question regarding what aspect of the paper which this thread is the focus of cannot be understood and analyzed by someone not in climate science.
Leif Svalgaard says:October 29, 2012 at 11:06 am
“I found the three peaks [and the 61-yr peak] long time before you”
Leif, you are further claiming that you confirmed my results.
Are you now claiming that the planetary influence on the sun, including the 61 yr cycle, was discovered by you? And that you rejected my paper not because erroneous but because you opposed that “your discovery” could be punished by me?
I thought that you opposed the planetary theory of solar variation because in your opinion no evidences existed!
I believe that also Anthony and everybody else thought that you were opposing the theory.
To Anthony
Anthony, please, note Leif’s metamorphosis. He is trying to become a butterfly!
REPLY: well at least he isn’t making legal threats to journal editors – A
sunshinehours1 says:
October 29, 2012 at 11:46 am
Leif: “From c) it is evident that the peak in the 2000s was higher than in the 1930s.”
Get your eyes checked.
http://www.leif.org/research/HMF-Briffa-Detail.png
Enough said!
This is addressed to S & S (Svalgaard and Scafetta)
Vuk’s sunspot formula is a CLASSIC
http://www.vukcevic.talktalk.net/SSN.htm
solar science or numerology makes no difference.
S & S take a note
Vuk’s next CLASSIC
http://www.vukcevic.talktalk.net/EarthNV.htm
climate science or numerology makes no difference.
S & S please do go on. LOL.