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 30, 2012 at 9:21 am
And it performs very well in reconstructing all known major solar and climatic patterns.
In your paper you say “reasonably well”, not ‘very’, and with good reason as your Figure shows spectacular failures: http://www.leif.org/research/Scafetta-Failure.png e.g. predicting what is the lowest cycle in a 100 years to be higher than the super cycle 19. It seems that peer-review had failed you.
To the readers,
Leif continues to tell lies after lies and use misleading statements against my research.
I simply wish Anthony realizes that there is something wrong with Leif’s way to argue.
Only by reading my papers, one can really understand what I wrote. So,do not trust Leif’s presentation of my works. Read them and form your opinion
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
Just responding to Leif’s false statements which, by the way, are already responded and discussed in my papers.
1) the formulae are arbitrary and numerological
Re: No, it is not. The folmulae that I use are very specific and rooted in astronomy and physics and data analysis.
2) the mechanisms are un-physical, e.g. your fusion argument ignores the fact that it takes 250,000 for the fusion energy to exit the core washing out any shorter periodicities
Re: Leif is thinking about random diffusion of photons, which is slow. But he does not know that energy can also propagate via sound-wave like mechanisms. These propagate very fast. For example, when we talk particles of gas exit our mouth and diffuse relatively slowly in the air, however the pressure perturbation they produce propagates fast as a sound wave, and we can hear each other talking.
3) you misuse data, e.g. the auroral data we discussed at length already
Re: I used the data as published. Leif claims that the aurora data are wrong because as they are they would support a planetary influence on the sun or earth. If my conclusion is wrong because the data are wrong or they are too short and the analysis is somehow misleading is something that needs to be properly investigated. Just saying the data are wrong is not a valid argument. Note that a planetary harmonical signature in the aurora records have been noted by numerous authors even by aurora experts in the 19th century.
4) failure to account for e.g. the Maunder Minimum.
Re: The Maunder minimum as well as the other grand solar minima are clearly recovered by my model. See figure 5 and 6 in
http://www.sciencedirect.com/science/article/pii/S1364682612000648
Leif Svalgaard says:
October 30, 2012 at 4:49 am
GSN should not be used anymore as it is not calibrated correctly
Ok, that may be so. Although my North Atlantic Precursor data collection and assemblage is far from perfect (just raw data with no weighting), but it does appear that from 1760 to present, the NAP’s correlation to the GSN is a bit closer than to the SSN.
http://www.vukcevic.talktalk.net/GSN-NAP.htm
Either way , geological records in the N. Atlantic show that the solar influence may be an important if not fundamental contributing factor.
I understand that you will and why will disagree, no mechanism or physical explanation available etc. etc. but it would be less than wise to totally ignore possibility of a direct or indirect link, but we have been here before.
Anthony Watts 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-1129057
Fair enough, although [snip — mod.]
Nicola Scafetta says:
October 30, 2012 at 9:21 am
And it performs very well in reconstructing all known major solar and climatic patterns.
Even Vuk does better than you: http://www.leif.org/research/Scafetta-Failure-Big.png
Rarely does one see such failures: Maunder Minimum is wrong, phases around 1800 and 1900 are wrong, cycle 13-24 are wrong, cycle 19 is wrong, the coming minimum [which you called a Maunder-type minimum] is higher than the minimum around 1900, etc. I would be ashamed to claim that this is very well>/b> reconstructed; it is terrible. As I said, peer-review has let you down this time. Perhaps you could show the reviews for this paper? IMHO all reviews should be published too, so editors and reviewers can’t easily do [as you called it] ‘strange things’. Don’t you agree?
October 30, 2012 at 10:33 am
Nicola Scafetta says:
October 30, 2012 at 9:21 am
And it performs very well in reconstructing all known major solar and climatic patterns.
Even Vuk does better than you: http://www.leif.org/research/Scafetta-Failure-Big.png
Rarely does one see such failures: Maunder Minimum is wrong, phases around 1800 and 1900 are wrong, cycle 13-24 are wrong, cycle 19 is wrong, the coming minimum [which you called a Maunder-type minimum] is higher than the minimum around 1900, etc. I would be ashamed to claim that this is very well reconstructed; it is terrible. As I said, peer-review has let you down this time. Perhaps you could show the reviews for this paper? IMHO all reviews should be published too, so editors and reviewers can’t easily do [as you called it] ‘strange things’. Don’t you agree?
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-1129008
This is only a fact in Courtney’s fantasy, since he hasn’t provided any shred of evidence for this assertion.
Why doesn’t Courtney uses this opportunity to try to get a PhD after writing some thesis, in which he presents this new, revolutionary scientific method, called “eyeballing”, with which he is able to finally and ultimately refute global warming? Then he even could legitimately call himself, “Dr. Courtney”.
Courtney is asserting here, results from a trend analysis where the trends do not show any statistical significance whatsoever allow conclusions about a reversal of a trend, here from a warming to a cooling trend. His reasoning does not have any scientific validity at all. Again, he is just proving that he is absolutely clueless, regarding what are scientifically valid conclusion from statistical analysis.
I’m not aware of any statistical analysis presented by Courtney where it is demonstrated that this assertion by him about the three decades was true. I have only seen that he has repeatedly made this assertion without providing any proof. Perhaps he believes, the endless repetition of the same unproven assertion makes this assertion true with time.
But for the sake of the argument, assuming his assertion about the tree decades was true, the following conclusion he draws from this,
lacks again any scientific validity. The failure of the test for statistical significance in a time series does not allow the conclusion that a trend is absent.And “stopped” means the same as absent. Perhaps, the slope of the trend decreased? But not even that would be a valid scientific conclusion from the changed significance. A decrease in statistical significance of a trend from one period to the next period doesn’t by itself even allow the conclusion that the trend slope decreased, since the statistical significance depends both on the trend slope and on the properties of the fluctuations overlaying the trend within the time period, the amplitude and how the fluctuations are distributed over the time interval. Statistical significance also decreases when the amplitude of the fluctuations increases, even if the trend slope stays the same.
In summary, Courtney abuses statistical analysis and produces unscientific nonsense as “reasoning” for his assertion that global warming “stopped”. His assertion is without any scientific merits.
vukcevic says:
October 30, 2012 at 10:24 am
I understand that you will and why will disagree, no mechanism or physical explanation available etc. etc.
No, not really. It is more that NAP is not defined and that the correlation is lousy.
Nicola Scafetta says:
October 30, 2012 at 10:18 am
Leif continues to tell lies after lies and use misleading statements against my research.
You have still not produced the reviews or the comparisons with other planetary predictions.
Perlw1tz;
blah, blah, blah….
You STILL haven’t answered my questions.
Richard S Courtney says:
That’s not science. It is just curve fitting…epicycles. “Recovery from the LIA” is a meaningless phrase. What CAUSED such a rise in temperature?
You are just engaging in cherry-picking here. Why did you choose to look at decadal periods? Why did you decide to look at 90% confidence? It is simply because it gives the answer that you want. There is no reason to expect that the climate system forced with continuing increases in greenhouse gases will always show warming with greater than 90% confidence over decadal periods. In fact, climate models forced with continuously increasing greenhouse gases will show periods of more than a decade over which the trend line is not only not increasing with 90% confidence but for which the trend line is in fact negative.
I see that Mr Perlwitz is still engaging in his habit of writing and posting L-O-N-G comments throughout his workday. As a taxpayer, I call that misappropriation of public funds. I doubt that arguing with commentators on blogs is in Perlwitz’ job description.
That said, Perlwitz is still trying to convince intelligent readers that Down is Up, Ignorance is Strength, and 16 years of flat temperatures is AGW. As if. I showed in my links [around 6 pm yesterday] that global temperatures have been flat. Perlwitz asserts otherwise. Perlwitz is wrong.
Dr. S: No, not really. It is more that NAP is not defined and that the correlation is lousy.
To the contrary: correlation is far above what ‘random walk’ would produce, each major rise or fall in the solar activity has corresponding movement in the N. Atlantic.
http://www.vukcevic.talktalk.net/GSN-NAP.htm
vukcevic says:
October 30, 2012 at 11:21 am
“No, not really. It is more that NAP is not defined and that the correlation is lousy.”
To the contrary
What do you call the spectacular failure in the 1730s?
Friends:
I have read the diatribe at October 30, 2012 at 10:51 am from the troll.
It makes many untrue assertions and demonstrates the anti-scientific nature of the troll.
Importantly, the diatribe makes blatantly wrong assertions concerning statistical concepts. In light of the true subject of this thread, it is surprising that a climastrologist would want to proclaim his ignorance of statistical concepts so blatantly.
The fundamental point of his post is that the troll claims the discussion was not about whether global warming stopped 16 years ago. His diatribe quotes me saying
And says
In fact the “fantasy” is his.
At October 29, 2012 at 5:43 pm the troll wrote
The subsequent debate was about that question which the troll posed.
There is no point in refuting the remainder of the troll’s diatribe. It is all untrue and based on similar delusional fantasies. So, I will not feed the troll.
Richard
Leif Svalgaard says:
October 30, 2012 at 10:03 am
Nicola Scafetta says:
October 30, 2012 at 9:21 am
And it performs very well in reconstructing all known major solar and climatic patterns.
In your paper you say “reasonably well”, not ‘very’, and with good reason as your Figure shows spectacular failures: http://www.leif.org/research/Scafetta-Failure.png e.g. predicting what is the lowest cycle in a 100 years to be higher than the super cycle 19. It seems that peer-review had failed you.
and
Leif Svalgaard says: October 30, 2012 at 10:33 am
Leif is doing his best to defame and mislead. He should read the paper instead with an open mind. But he is simply filled of rancor and hate.
The model proposed in the paper is based only of three harmonics. Getting the full solar signal in its minimal details with just three harmonics is evidently impossible. Nowhere in the paper it is claimed that the proposed model is infinitely precise. It gets the major patterns within a statistical error. The multidecadal/secular/millennial patterns are well recovered, while for the dacadal pattern it is more difficult and this is written in the paper.
For analogy, ocean tides are predicted with great precision only with 30-40 astronomical harmonics, not just three. So, my model can be improved, and this is said in the paper.
Leif simply does not understand that science progresses by steps. Leif would be right if he could propose an alternative model based on internal solar dynamics alone that performs better than mine in hindcasting the solar patterns. But he does not have such a model. So, he defame my work simply because it is not the “final and ultimate” work in solar physics and improvements can be done with further research, of course. This is what happens everywhere in science.
Moreover, Leif is completely misunderstanding my model. For example, when he says
“predicting what is the lowest cycle in a 100 years to be higher than the super cycle 19”
Leif is thinking about sunspots which were quite numerous during cycle 19. However, my model is more an abstract estimate of the total solar irradiance modulation. There is no experimental evidence that the total solar irradiance of cycle 19 (around 1960) was higher than that of cycle 23 or of cycle 18, for example. And the solar reconstructions vary. See here for example about one solar reconstruction based on Hoyt and ACRIM that contradicts Leif:
http://wattsupwiththat.com/2012/09/06/soon-and-briggs-global-warming-fanatics-take-note-sunspots-do-impact-climate/
The sunspot cycle and the total solar irradiance cycle are strongly “linearly” related only in Leif’s imaginative model. Indeed, the two cycles may differ in multiple patterns such as amplitude and phase. So, in his comments, Leif is simply using his (mis)understanding of solar physics mixed with his strong desire of defamation.
Leif Svalgaard says:
October 30, 2012 at 10:58 am
“You have still not produced the reviews or the comparisons with other planetary predictions.”
What is this guy talking about? Why review should matter given that the papers passed the review process by numerous referees far more qualified than Leif? Why comparison with other planetary models should matter? The comparison must be done with solar and climate records, that is what done in my papers.
To Anthony:
do you really approve Leif’s way of reasoning? Do you really think that Leif, or his friends, could give a valid and unbiased review of my papers with the above sloppy way of reasoning?
With such a reasoning methodology there would be no one paper in solar physics and geophysics that would pass Leif’s review!
Now I am too busy, so I leave this discussion.
joelshore says:
“What CAUSED such a rise in temperature?”
Good question. Nobody knows for sure. Good misdirection, too. Because Mann’s hokey stick always was an invented fiction.
We don’t know for sure what caused the LIA. But the subsequent recovery has been along the same warming trend line — with no acceleration — since then. The global warming trend has been the same, whether CO2 was low or high. Thus, the only reasonable conclusion is that CO2 does not cause global warming. Or if it does, the effect is so minuscule that it is not even measurable, and thus it can be completely disregarded for all practical purposes. AGW is simply an evidence-free belief system.
Nicola Scafetta says:
October 30, 2012 at 11:42 am
Leif is doing his best to defame and mislead. He should read the paper instead with an open mind.
I show a Figure from your paper. Its failures speak for themselves.
Leif is thinking about sunspots which were quite numerous during cycle 19. However, my model is more an abstract estimate of the total solar irradiance modulation.
You show a comparison between sunspots and your ‘model’
Why review should matter given that the papers passed the review process by numerous referees
As I said, peer-review failed for your papers. It is of interest to read the faulty reviews.
The comparison must be done with solar and climate records, that is what done in my papers.
With the spectacular failures evident in http://www.leif.org/research/Scafetta-Failure-Big.png
With such a reasoning methodology there would be no one paper in solar physics and geophysics that would pass Leif’s review!
I review a couple dozens each year, and many good ones pass. Bad ones flunk, like yours did.
Now I am too busy, so I leave this discussion.
This has not been a discussion in any real sense of the word. So nothing is lost by you being ‘too busy’.
joeldshore:
I am replying to your post at October 30, 2012 at 11:10 am.
You say
It IS science.
Much of modern science would not exist without the scrupulous examination of epicycles by Copernicus. In science one starts with examination of phenomena and then moves towards explanation of them. It is NOT science to ignore the behaviour of phenomena and merely to guess their causes.
Nobody knows what caused recovery from the LIA. That is why the long-term cycle which produced the LIA is worthy of investigation. But we do know that anthropogenic GHG emissions cannot have caused the recovery from the LIA.
And you say of my assessment of the recent cessation of global warming by use of statistical confidence.
Clearly, you did not read the assessment I wrote and you claim to be addressing. My assessment answered your questions.
My choice of decadal periods was arbitrary but provided four sub-sets of the data set for the considered period since 1970 (i.e. the longest period which the troll introduced to the discussion at October 29, 2012 at 9:37 am). Four sub-sets is the minimum required to indicate a series of similar subsets for comparison to the most recent subset (and before you ask, two is not an adequate series).
As I said, any confidence could have been chosen, but a trend is observed in each of the first three sub-sets at 90% confidence. No trend is observed in any of them at 95% confidence.
The answer I wanted was the ability to observe a trend in those three sub-sets and that answer turns out to be 90% confidence.
Climate models only “show” how they behave, and that is not relevant to the issue of how the real world is observed to have behaved.
The important point is that the analysis which I provided indicates global warming which is observable with 90% confidence stopped 16 years ago. Reasons why it stopped are not known, but it stopped.
You are welcome to discuss possible reasons for that cessation. Alternatively, you can copy the troll and pretend it did not stop, but that would be a rejection of both science and logic
Richard
I rephrased and resubmitted my posting that was snipped here:
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-1129057
Is the resubmitted one going to be posted here? I just want to know.
REPLY: I assume you can answer this question yourself – Anthony
Nicola Scafetta says:
October 30, 2012 at 11:42 am
See here for example about one solar reconstruction based on Hoyt and ACRIM
We went over that one. It is flawed. Here is what it really looks like: http://www.leif.org/research/Temp-Track-Sun-Not.png
Leif Svalgaard says:
October 30, 2012 at 11:27 am
What do you call the spectacular failure in the 1730s?
It just show that even you sometimes could be correct, i.e. sunspot count at early 18th century was 10% underestimated, or have you given up on the idea ‘no grand maxima’?
http://www.vukcevic.talktalk.net/SSN-NAP.htm
N. Atlantic data, most of it from Danish records, Danes were keen observers of that stretch of water, are far more accurate than any solar or climate data of the period.
North Atlantic controls the CET, which also shows that solar output of the early 18th century is underestimated.
http://www.vukcevic.talktalk.net/CET-NAP.htm
and finally
http://www.vukcevic.talktalk.net/CET-NAP-SSN.htm
Now if you whish to do something beneficial for the humanity (rather than waste your time, which you do so competently) email me and we can sort out N. Atlantic geo-solar puzzle as demonstrated independently by NAP (as above) and http://www.vukcevic.talktalk.net/EarthNV.htm
Let me know when you embark on ‘the road to Damascus’ and you will not regret it.
vukcevic says:
October 30, 2012 at 1:01 pm
email me and we can sort out N. Atlantic geo-solar puzzle
Thank you for your kind offer, but perhaps you should consult a ‘real expert’ like Nicola, provided he is not too busy and can find time. He has all the answers already.
In reply to the comment by richardscourtney 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-1129369
Courtney quotes a previous statement made by himself (boldface by me):
The discussion was about global warming since 1970 and the fact that it stopped 16 years ago.
and my reply to it:
This is only a fact in Courtney’s fantasy, since he hasn’t provided any shred of evidence for this assertion.
He now has commented my reply as follows:
I do not believe that my reply saying that the fact was only one in Courtney’s fantasy, can be really misunderstood by anyone who is clear in his mind, in a way that it referred to his meta statement about what the discussion was about, but not to what Courtney explicitly claimed the fact was, that global warming “stopped”, particularly since I also mentioned the missing evidence for it in the same sentence.
Thus, I do not believe in some innocent misunderstanding on the side of Courtney here, unless he has some serious problems in understanding statements in written English when he reads them. Well, that would create some serious obstacles for his PhD thesis about “eyeballing” as new, revolutionary scientific method to refute global warming.
The alternative possibility I see here is that he is just bluntly lying now, as a mean of distraction, after I have thoroughly debunked his unscientific, nonsensical “reasoning”, which he has used to support his unproven and baseless assertion, according to which global warming “stopped” some time ago.
Jan P Perlwitz says:
October 30, 2012 at 10:51 am
“Why doesn’t Courtney uses this opportunity to try to get a PhD after writing some thesis, in which he presents this new, revolutionary scientific method, called “eyeballing”, with which he is able to finally and ultimately refute global warming? Then he even could legitimately call himself, “Dr. Courtney”.
“Eyeballing” is an essential step in analysis. Even the most sophisticated statistical test you can throw at a given set of numbers has assumptions built in which may, or may not, be applicable for the data at hand. The human brain is an amazing pattern recognition device which can generally, sometimes with the aid of some basic filtering/smoothing, cut through the clutter and identify what is truly happening.
Any rigorous data analysis must include sanity checks at fundamental levels to establish that the result makes actual sense. In the real world, where engineers build systems which must function properly or there are immediate and severe consequences, a failure to establish the fundamental “rightness” of one’s analysis can buy you a quick ticket to oblivion.
In this particular instance, Dr. Perlwitz’ admonition is akin to the lover caught in flagrante delicto who demands of his significant other, “Who’re you going to believe? Me, or your lying eyes?”
joeldshore says:
October 30, 2012 at 11:10 am
More chaff from Dr. Shore. No further comment needed or merited.
D Böehm says:
October 30, 2012 at 11:56 am
“We don’t know for sure what caused the LIA.”
But, we do know some things it was not. It was not humans.
vukcevic says:
October 30, 2012 at 1:01 pm
N. Atlantic data, most of it from Danish records
congratulations! you have discovered a 200-yr cycle in NAP that matches the 100-yr cycle in SSN every 2nd cycle. This could be the discovery of the century, or of the last centuries.