More facts against the Mann – 'late 20th century warming has not been unique within…the past 750 years '

Earlier this week, in Facts against the Mann, we noted how some ice core data cast doubt on Michael E. Mann’s recent claim that: 

“overall warmth of the globe and northern hemisphere today is substantially greater than during Medieval time”

This was made in the context of an invective filled rebuttal in the Nevada City, CA Union newspaper, over a column questioning the validity of Mann’s work, citing McIntyre and McKittrick’s work. Sauer wrote:

McIntyre and McKitrick’s work led to a U.S. Senate investigation that debunked Mann’s hockey stick theory that 1998 was the hottest year in the last 1,000. The Senate investigation also found the study of the social networking of the paleoclimatology world showed how close it was and how often a small group of scientists both co-wrote and peer-reviewed papers for each other. In addition, no statisticians were ever involved in their research work or peer review articles.

In response, Mann hauled out the usual tired old hate-filled libel:

Mr. Sauer parroted baseless talking points that have their origin in fossil-fuel industry-funded climate change denial propaganda, not honest scientific discourse.

Source: http://www.theunion.com/opinion/columns/18308425-113/michael-mann-columnist-peddles-discredited-fossil-fuel-industry

Jim McIntosh writes on the WUWT Facebook page:


[A] recent paper suggests tree ring proxies (which underpin Mann’s Hockey Stick Graph that largely kicked off the global warming scare) have underestimated past temperatures, which creates the misimpression that current warming is unique.

esper-2015-tree-ring-compare

Recently published hard science. And bound to never be reported in the media.

” In other words, the new methodology allowed the researchers to capture the low-frequency climatic signals that were systematically eliminated in the MXD data sets. Thus, as a consequence, earlier warm periods during the late 14th and 15th, and 17th centuries “appear warmer” and “have been retained” by this new method, leading the team of six researchers to conclude that “late 20th century warming has not been unique within the context of the past 750 years.”


From the Esper et al. 2015 paper, note that the black line represents the instrumental record. The reconstruction, in red, shows Medieval Warming Period is clearly seen to have temperatures greater than the current modern period. As for the divergence of the instrumental record against the reconstruction, it is important to note that the trees sensing temperature aren’t near human habitation as most of our observing thermometers are, but rather in the Pyrenees mountains.

esper-2015-tree-ring-reconstruction

Here is the paper by Esper. et al. 2015, bold mine.

LONG-TERM SUMMER TEMPERATURE VARIATIONS IN THE PYRENEES FROM DETRENDED STABLE CARBON ISOTOPES

Abstract:

Substantial effort has recently been put into the development of climate reconstructions from tree-ring stable carbon isotopes, though the interpretation of long-term trends retained in such timeseries remains challenging. Here we use detrended δ13C measurements in Pinus uncinata treerings, from the Spanish Pyrenees, to reconstruct decadal variations in summer temperature back to the 13th century. The June-August temperature signal of this reconstruction is attributed using decadally as well as annually resolved, 20th century δ13C data. Results indicate that late 20th century warming has not been unique within the context of the past 750 years. Our reconstruction contains greater amplitude than previous reconstructions derived from traditional tree-ring density data, and describes particularly cool conditions during the late 19th century. Some of these differences, including early warm periods in the 14th and 17th centuries, have been retained via δ13C timeseries detrending — a novel approach in tree-ring stable isotope chronology development. The overall reduced variance in earlier studies points to an underestimation of pre-instrumental summer temperature variability derived

from traditional tree-ring parameters.

Full paper here: https://www.blogs.uni-mainz.de/fb09climatology/files/2012/03/Esper_2015_Geochron.pdf

What I find most interesting is their graph showing how they calibrated the  δ13C data against the instrumental temperature record. While not a perfect match, with R values being rather low, the reconstruction does seem to capture the trend effectively.

esper-2015-tree-ring-calibrationIt seems to me, that δ13C analysis is a better match than tree ring widths by themselves for determining past temperatures, though like anything to do with tree growth, there are many other factors determining growth as outlined in Liebig’s Law of the Minimum. Hence, uncertainty will likely always be large.

[added] I wonder if  Mann’s Bristlecone Pine tree core samples from MBH98 still survive, and what they might say if a δ13C analysis like Esper did was run on them?

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Admad
September 25, 2015 11:10 am
xyzzy11
Reply to  Admad
September 25, 2015 3:20 pm

Can people please NOT just add a link with no additional comments – I like to know (and presume that others do too) what the link I’m clicking is about.

Menicholas
Reply to  xyzzy11
September 25, 2015 3:52 pm

I never click on such links.
If someone is too lazy to make an actual comment, or even provide an explanation of the link, they have not earned any of my time or attention.
BTIJM.

ferdberple
Reply to  xyzzy11
September 25, 2015 7:20 pm

yet another weiner peter?

Alan Robertson
Reply to  xyzzy11
September 25, 2015 11:18 pm

YouTube links (without brackets) will display a screencap and title.

Reply to  xyzzy11
September 26, 2015 12:50 pm

Back in the day, bald links were known as hURLs.

DonM
Reply to  Admad
September 25, 2015 8:15 pm

[https://www.clickonthisyouidiot.com]

Luke
September 25, 2015 11:17 am

This reconstruction is based on one location so it does not represent a fundamental challenge to Mann’s global reconstruction.

Neville
Reply to  Anthony Watts
September 25, 2015 3:51 pm

I think Anthony should know that Luke haunted Jennifer Marohasy’s site for years. So far he’s been well behaved here, but he gets very upset very quickly.
The Mann is Luke’s great hero and he especially likes it when fools uses the wrong data for temp reconstruction and use data upside down etc. Luke just loves this kind of deception.

Steve from Rockwood
Reply to  Anthony Watts
September 25, 2015 4:13 pm

Sheep Mountain. The irony burns.

Felix
Reply to  Anthony Watts
September 25, 2015 5:58 pm

Saying one chronology was heavily weighted is not the same as saying it was the only one heavily weighted. The new paper does not in itself refute MBH 98 or any of the many of papers showing the recent warming is unique for hundreds of years. The new paper certainly makes no such claim. It would be useful to see someone include this data in a global reconstruction to see if it has a significant impact.

Granddaughter Ava
Reply to  Anthony Watts
September 26, 2015 10:49 am

Andy wrote: “if Mann heavily weights a proxy in one location to make a global claim, does that make it OK for him, but not for anyone else?”
Neither YOU nor Mann should be using a proxy from one location (or overweighted at one location) to draw conclusions about hemispheric or global temperature. M&M and others proved a decade ago that the methodology in Mann’s original Hockey Sticks was badly flawed.
McShane and Wyner and the debate they prompted indicates to me that the published confidence interval around all published reconstructions depends on the statistical model applied and probably are too narrow.
Esper (2015) is important because it shows that dC13 data produces a different reconstruction that retains more variability than reconstructions using TRW or MXD measurements at the same site.

Lady Gaiagaia
Reply to  Luke
September 25, 2015 11:28 am

Proxy data from all over the globe show the HS to be bogus.

Reply to  Luke
September 25, 2015 11:31 am

You sir, are clearly not for real!!

Editor
Reply to  Luke
September 25, 2015 2:02 pm

If you study proper scientists such as. H Lamb, you will find many similar examples like this one, and they are spread worldwide.

Reply to  Paul Homewood
September 25, 2015 3:24 pm

Paul,
I studied H. H. Lamb long, long ago and by doing so knew that the CO2 scare was horse feathers from the get-go. It is a crying shame that they have turned the CRU that he founded into the citadel of falsehoods that it is now. A crying shame.

richardscourtney
Reply to  Luke
September 25, 2015 2:11 pm

Luke:
You say

This reconstruction is based on one location so it does not represent a fundamental challenge to Mann’s global reconstruction.

Even Mann did not say his fr@udulent reconstruction was “global”: he claimed it was only for the Northern Hemisphere.
If you desire to defend the indefensible then you could at least try to know what you are trying to defend.
Richard

Chip Javert
Reply to  richardscourtney
September 25, 2015 2:25 pm

Richard
“…[D]efend[ing] the indefensible then you could at least try to know what you are trying to defend.”
LOL. Good point, but I think the warmest horse is out of the barn on that one.

old construction worker
Reply to  richardscourtney
September 25, 2015 10:32 pm

@Richards “Even Mann did not say his fr@udulent reconstruction was “global”: he claimed it was only for the Northern Hemisphere.”
That’s not my understanding. After the HS was broken others were saying the MWP was only a Northern Hemisphere thing. not world wide. correct me if I’m wrong.

richardscourtney
Reply to  richardscourtney
September 26, 2015 1:23 am

old construction worker:
You write:
blockquote>@Richards “Even Mann did not say his fr@udulent reconstruction was “global”: he claimed it was only for the Northern Hemisphere.”
That’s not my understanding. After the HS was broken others were saying the MWP was only a Northern Hemisphere thing. not world wide. correct me if I’m wrong.<
I write to correct you.
The pertinent paper is
Mann ME, Bradley RS & Hughes MK, ‘Global-scale temperature patterns and climate forcing over the past six centuries’, Nature, v.392, 23 April 1998
and it can be read here.
The paper’s title says it addresses “Global-scale temperature patterns and climate forcing” and this does imply that the paper provides global scale reconstructions, but the paper’s contents provide northern hemisphere (NH) reconstructions and mentions some asserted global effects.
Its Abstract says

Spatially resolved global reconstructions of annual surface temperature patterns over the past six centuries are based on the multivariate calibration of widely distributed high-resolution proxy climate indicators. Time-dependent correlations of the reconstructions with time-series records representing changes in greenhouse-gas concentrations, solar irradiance, and volcanic aerosols suggest that each of these factors has contributed to the climate variability of the past 400 years, with greenhouse gases emerging as the dominant forcing during the twentieth century. Northern Hemisphere mean annual temperatures for three of the past eight years are warmer than any other year since (at least) AD 1400.

The first sentence of the Abstract implies that the reconstructions in the paper are “Spatially resolved global reconstructions of annual surface temperature patterns over the past six centuries” but those plots are NOT the so-called ‘hockey stick’ which – as the final sentence in the Abstracts says – is of “Northern Hemisphere mean annual temperatures”.
The (possibly deliberate) ambiguity about geographical extent of the temperature reconstructions is also in the body of the paper, for example, this

The long-term trends in the reconstructed annual mean NH series (Fig. 5b) are quite similar to those of decadal Northern Hemisphere summer temperature reconstructions, showing pronounced cold periods during the mid-seventeenth and nineteenth centuries, and somewhat warmer intervals during the mid-sixteenth and late eighteenth centuries, with almost all years before the twentieth century well below the twentieth-century climatological mean. Taking into account the uncertainties in our NH reconstruction (see Methods), it appears that the years 1990, 1995 and now 1997 (this value recently calculated and not shown) each show anomalies that are greater than any other year back to 1400 at 3 standard errors, or roughly a 99.7% level of certainty. We note that hemispheric mean values are not associated with globally or hemispherically uniform trends. An example of the global pattern for an historically documented35 ‘‘very strong’’ El Nin˜o year (1791) is shown in Fig. 6 top panel, demonstrating the classic warm eastern tropical Pacific and cold central North Pacific sea surface temperature patterns. Analysis of ENSO variability in these reconstructions is discussed in more detail elsewhere.

The sentence saying
“We note that hemispheric mean values are not associated with globally or hemispherically uniform trends.”
is hidden in the paragraph I here quote.
Clearly, the temperature reconstruction known as the ‘hockey stick’ is for the NH but the paper implies its reconstructions are global. Competent peer review would have demanded that this ambiguity be clarified.
I hope this answer is sufficient.
Richard

John XX
Reply to  Luke
September 25, 2015 3:05 pm

Good point. There are no references to any of Mann’s papers in this paper. The paper does not even contain the word “global”.

DEEBEE
Reply to  Luke
September 26, 2015 4:55 am

When you get time from your skywalks get, go to Steve Mc webs site and find the small number, as in a handful of tree that contributed to Mann-rection

MarkW
Reply to  Luke
September 26, 2015 7:28 am

Felix, it would help if you actually understood the concepts you were trying to defend.
The issue was the claim that it is invalid to use one proxy to represent the entire world.
As has been pointed out, for several time periods, Mann’s paper did just that.
As to being the warmest for the last couple of hundred years, so what. It’s warmer than it was at the bottom of the little ice age. Most people would consider that to be a good thing.

Bob B.
September 25, 2015 11:25 am

“I wonder if Mann’s Bristlecone Pine tree core samples from MBH98 still survive, and what they might say if a δ13C analysis like Esper did was run on them?”
Is that a wood chipper I hear starting up?

Resourceguy
Reply to  Bob B.
September 25, 2015 12:39 pm

No, just arson

Otteryd
Reply to  Resourceguy
September 25, 2015 1:26 pm

There’s been a lot of arson about here recently. ( pun??)

September 25, 2015 11:26 am

Dear Dr. Mann;
If you should happen to see this, please note how Esper et al. changed colors on their graph when they changed datasets; a much more elegant and forthright method than the one you used.
Have a good day Sir, from one of the persons you banned from your facebook page

Marcus
Reply to  Paul Jackson
September 25, 2015 11:48 am

Hockey Stick = MANN made Glo-Bull Warming

Greg Woods
Reply to  Marcus
September 25, 2015 12:37 pm

Actually, Hockey Stick is HS; Horse Sh.. er, Horse Puckey

Michael Jankowski
September 25, 2015 11:27 am

The oceans2k results say we’re far from anomalously warm. Seems that Mann’s results contradict them…yet both are used to portray that man has has a large fingerprint in creating unnatural warming.

September 25, 2015 11:32 am

Since the Holocene Optimum 8000 years ago the earth has been in a gradual overall cooling trend which has continued up to today punctuated by spikes of warmth such as the Roman ,Medieval and Modern warm periods.
The main drives of this are Milankovitch Cycles which were more favorable for warmer conditions 8000 years ago in contrast to today , with prolonged periods of active and minimum solar activity superimposed upon this slow gradual cooling trend giving the spikes of warmth I referred to in the above and also periods of cold such as the Little Ice Age.
Further refinement to the climate coming from ENSO, volcanic activity , the phase of the PDO/AMO but these are temporary earth intrinsic climatic factors superimposed upon the general broader climatic trend.
All the warming the article refers to which has happened since the end of the Little Ice Age, is just a spike of relative warmth within the still overall cooling trend due to the big pick up in solar activity from the period 1840-2005 versus the period 1275-1840.
Post 2005 solar activity has returned to minimum conditions and I suspect the overall cooling global temperature trend which as been in progress for the past 8000 years ago will exert itself once again.
We will be finding this out in the near future due to the prolonged minimum solar activity that is now in progress post 2005.

Jaime Jessop
Reply to  Salvatore Del Prete
September 25, 2015 2:31 pm

The continued reluctance of consensus climate science to properly place current global temperatures within the context of the entire Holocene and the single-minded concentration upon climate models which predict (with little hard evidence) a complete reversal in a matter of years the natural decline in global temperatures which has taken place over many thousands of years is a betrayal of the scientific method and of the people who depend upon science to reliably inform them about the world in which they live.

Menicholas
Reply to  Jaime Jessop
September 25, 2015 3:58 pm

You got that right, brother!

lokenbr
Reply to  Jaime Jessop
September 26, 2015 12:01 am

Amen.

September 25, 2015 12:09 pm

Conclusions
“As a consequence, earlier warm periods
during the late 14th and 15th centuries appear warmer,
though not statistically significant, compared to the late
20th century.
A major constraint of the new reconstruction is the
substantial difference in recent temperature trends caused
by post-1850 δ13C correction procedures. The correction
applied here, accounting for atmospheric 13C/12C ratio
and plant physiological effects, appeared most suitable as
it produced a timeseries without any trend in residuals
after regressing against instrumental temperatures. However,
developing objective criteria for post-1850 correction,
independent of the goodness of fit with instrumental
target data, are needed to establish δ13C based reconstructions
as an additional proxy for studying climate variations
over past millennia.”
read the section on the “correction” process..
ahem… adjusting raw data again…

gbaikie
Reply to  Steven Mosher
September 25, 2015 12:23 pm

–ahem… adjusting raw data again…–
Does this have anything to do with adjusting raw data.
One gets say pictures of say Pluto from raw data; which are processed to make images.
Altering the raw data, rather than a copy of the raw data, would be wrong

Chip Javert
Reply to  gbaikie
September 25, 2015 2:30 pm

gbaikie
You can do whatever you want to pictures of Pluto (or your selfies) – nobody is claiming that is scientific evidence supporting global warming (or any other) theory.
If you understood science, you wouldn’t have to be reminded of this.

Jared
Reply to  Steven Mosher
September 25, 2015 1:24 pm

It’s okay to adjust if it shows unprecedented warming, so why not adjust to show this is a ho hum nothing special warming.

Reply to  Jared
September 25, 2015 2:10 pm

Actually SST raw data is adjusted DOWN

Reply to  Steven Mosher
September 25, 2015 2:07 pm

Christ Mosh!
9:09 am west coast time, and youre hard at work already?

Reply to  davideisenstadt
September 25, 2015 2:09 pm

Up at 6

Reply to  davideisenstadt
September 25, 2015 2:48 pm

well, I was up at 3 your time.
😉

Reply to  davideisenstadt
September 25, 2015 2:50 pm

BTW Mosh
If you think about degrees celsius is merely an anomaly…degrees kelvin minus a constant, no?
and really degrees kelvin is merely an anomaly itself…divergence from absolute zero.

geronimo
Reply to  Steven Mosher
September 26, 2015 12:31 am

It’s a temporal thing Mosh, there’s nothing wrong with adjusting raw data at the time when a weather station is moved/changed, or hasn’t worked. It’s adjusting raw data after it’s been used for 80-100 years that’s smelly.

MarkW
Reply to  Steven Mosher
September 26, 2015 7:35 am

I love the way warmists find one point that they don’t understand, and then harp on it over and over again.
Adjusting data is ok so long as you present the raw data, plus your methods and reasons for adjusting.
This allows others to review your adjustments and determine if they are reasonable and correct.
When your climate scientists start doing this, they will come in for a lot less criticism.

dmacleo
September 25, 2015 12:41 pm

what was the number of cones that drove the policy? iirc was somethign like 10 cones wasn’t it?
please correct me if I am wrong.

dmacleo
Reply to  dmacleo
September 25, 2015 12:42 pm

grr policy should read paper findings
sorry

September 25, 2015 12:41 pm

A caution related to taking one part of the globe and extrapolating global synchronicity (click on link below and then click on the “[PDF] from columbia.edu” link). Given what we currently observe under a given weather pattern variation/climate regime, it is often the case that certain warm and cold patterns describe a climate regime. The land will be cold here but warm there. Or maybe less cold here while warm there. Or an oceanic warm pool will shift positions with a cold pool (PDO anyone?). Or the jet stream loops further to the East instead of over the North American plains. Who is to say that during the MWP, there was NOT extensive Antarctic sea ice while Greenland was host to Viking farmers? A case in front of our noses: We have been and still are in a warm period and Antarctic sea ice has been above its mean.
So no, proxies all over the globe may not show a consistent, synchronized warm trace. Instead they may be marked by variations that could indeed be the pattern when a warm period is upon us, and is what Mann uses mistakenly to dismiss the existence of a global MWP climate regime. When a cold period is upon us, we will see a different pattern. If Mann is alive at that time, he may resurrect global warming as the Antarctic ice for example, begins to show evidence of shrinking. Why is that a good bet? Mann does not appear to be a person willing to learn. Unfortunately, this debate is peppered on both sides with folks like him.
https://scholar.google.com/scholar?hl=en&q=Inter-hemispheric+temperature+variability+over+the+past+millennium+Raphael+Neukom&btnG=&as_sdt=1%2C38&as_sdtp=

Mike the Morlock
September 25, 2015 12:49 pm

Invasion of Batu Khan[edit]
The vast Mongol hordes of around 35,000 mounted archers, commanded by Batu Khan and Subutai, crossed the Volga River and invaded Volga Bulgaria in the autumn of 1236. It took them a year to extinguish the resistance of the Volga Bulgarians, the Cumans-Kipchaks, and the Alani.
Sacking of Suzdal by Batu Khan in February 1238; miniature from the 16th-century chronicle.
In November 1237, Batu Khan sent his envoys to the court of Yuri II of Vladimir and demanded his submission. A month later, the hordes besieged Ryazan. After six days of bloody battle, the city was totally annihilated. Alarmed by the news, Yuri II sent his sons to detain the invaders, but they were soundly defeated. Having burnt down Kolomna and Moscow, the horde laid siege to Vladimir on February 4, 1238. Three days later, the capital of Vladimir-Suzdal was taken and burnt to the ground. The royal family perished in the fire, while the grand prince retreated northward. Crossing the Volga, he mustered a new army, which was totally annihilated by the Mongols in the Battle of the Sit River on March 4.
Thereupon Batu Khan divided his army into smaller units, which ransacked fourteen cities of modern-day Russia: Rostov, Uglich, Yaroslavl, Kostroma, Kashin, Ksnyatin, Gorodets, Galich, Pereslavl-Zalessky, Yuriev-Polsky, Dmitrov, Volokolamsk, Tver, and Torzhok. Chinese siege engines were used by the Mongols under Tului to raze the walls of Russian cities.[4] The most difficult to take was the small town of Kozelsk, whose boy-prince Vasily, son of Titus, and inhabitants resisted the Mongols for seven weeks, killing 4,000. As the story goes, at the news of the Mongol approach, the whole town of Kitezh with all its inhabitants was submerged into a lake, where, as legend has it, it may be seen to this day. The only major cities to escape destruction were Novgorod and Pskov. The Mongols were advancing on Novgorod but unexpectedly turned back at the site mentioned as Ignach Cross, of which the exact location is not known. Refugees from southern Rus’ moved mostly to the northeast, into the forested region with poor soils between the upper Volga and the Oka Rivers.
In the summer of 1238, Batu Khan devastated the Crimea and pacified Mordovia. In the winter of 1239, he sacked Chernigov and Pereyaslav. After many days of siege, the horde stormed Kiev in December 1240. Despite the resistance of Danylo of Halych, Batu Khan managed to take two of his principal cities, Halych and Volodymyr-Volynskyi. The Mongols then resolved to “reach the ultimate sea”, where they could proceed no further, and invaded Hungary and Poland.
Yes its Wikipedia, but the above gives you a good account. Oh and do note the dates, and that this is Russia. Ah can we say medieval warm period.
michael

Lady Gaiagaia
Reply to  Mike the Morlock
September 25, 2015 4:38 pm

Each Mongol soldier kept three or four ponies, with more animals in the logistics train, so imagine a ravening horde with perhaps 120,000 horses.

Jeff Norman
Reply to  Mike the Morlock
September 26, 2015 9:39 am

And where did all these Mongolians appear from? Currently most of Mongolia is a frozen wasteland for a good part of the year frequently afflicted by Zuds (deep deadly freezes that kill anything outside, like say war ponies). I believe Mongolia became something of a temperate garden at the start of the MWP allowing the Mongol hordes to flower.

Frans Caleeuw
Reply to  Mike the Morlock
October 5, 2015 6:02 pm

Very sensible explanation. About 700 – 800 years earlier (about 450 – 550 AD) a ‘mini-ice age ocurred and drove the Germanic and Slavic tribes to occupy totally or partly the Roman Empires ‘West and East’. The cooler weather up North was however favorable to the Southern regions at first drier but later wetter ones. The Middle East and North-Africa flourished both again. The population boom in Arabia supplied numerous nomad-warriors to both the Byzantines and Sassanids. After the devastating wars between those empires, some of these nomadic warriors were able to supplant them and conquer the entire Middle-East and North-Africa (700 – 800 AD).. Towards 900 – 1.000 AD they adopted a creed now known as Islam. The onset of a new warming and drier period wasn’t very beneficial for that region. The Crusaders came (1.100 AD) and won and finally the Mongols came also and devastated the entire Middle-East (1.250 AD).

September 25, 2015 1:22 pm

I recently cut down some trees in my garden.
Upon examination the pattern of tree rings shows no evidence that seasonal variation of temperature existed in previous years. i.e there was formerly no variation in temperature between winter and summer.
These finding are in striking contrast to the evidence provided by historical accounts.
I also searched in the local pond for the plane, MH370 and did not find it.
Hence, seasonal variation in temperatures did not formerly exist and the plane MH370 does not and did not ever exist.
When I extended my tree ring examination to show modern yearly variation the technique showed fundamental limitations. i.e. it failed to correspond to established reality.
As a result I have bodged the representation of my findings by chopping off the familiar modern period and replacing that section of the graph with some other stuff which was derived from another methodology.
The result of all of these efforts is frankly a big pile of shit which I intend to force upon the world, for ideological reasons. And for the sake of self-promotion.
People will still be discussing the fruits of my witless bullcrap, even in a decade or two.
Which is success of sorts.
In addition, MH370 has still not been found. Proving that my initially assessment is still valid.
P.S. thanks for all the money.

Reply to  indefatigablefrog
September 25, 2015 5:01 pm

I have three ash trees in my back yard which somehow have been missed by the Emerald Ash Borers that have invaded Ohio. I do not plan to cut them down unless the borers find them but they do point out the idiocy of using tree rings for determining temperature. I planted the trees about 20 years ago on the same day. They are about 50 feet apart. All three trees have different trunk diameters ranging from 10 to 14 inches.
Why are they all different?
DNA?, depth of water table?, amount of sun they receive?, variations in nutrients in the soil?
If Michael Mann we to cut them down and study their tree rings which one would he use to determine the temperature over the last twenty years?

Alx
Reply to  Raymond L. Blinn
September 25, 2015 6:35 pm

That’s easy. The one that supports his claims.

Reply to  Raymond L. Blinn
September 26, 2015 5:53 am

Short answer: none of them.
Since dendroclimatology fails to reproduce modern warming. The so-called divergence problem.
As explained here on wikipedia:
“While the thermometer records indicate a substantial warming trend, tree rings from these particular sites do not display a corresponding change in their maximum latewood density or, in some cases, their width. This does not apply to all such studies. Where this applies, a temperature trend extracted from tree rings alone would not show any substantial warming. The temperature graphs calculated from instrumental temperatures and from these tree ring proxies thus “diverge” from one another since the 1950s, which is the origin of the term. This divergence raises obvious questions of whether other, unrecognized divergences have occurred in the past, prior to the era of thermometers”.
It certainly does raise that question. It’s the question that we have all been asking.
The entire exercise also raises the question that you allude to. Which is the question of whether the temperature is actually the most significant factor in determining the growth rate of trees.
And even if it is, then how are we to eliminate the influence of other competing factors.
These are the questions that should have been asked, even if this enterprise had been a project for secondary school.
However, since the results were signed off by an “expert in the field”, the world failed to ask these questions and failed to demand the answers.
Then there is the issue of the truncation of a graph showing data from one methodology and the supplanting of the modern period with data derived using an altogether different technique.
At best misleading, at worst plain deception.
In summary what was presented is wrong in so many ways that it should be regarded as having almost no connection with reality whatsoever.
Throw in the fact that the scientist behind it was motivated to prefer a certain outcome and we are beyond wrong. We are beyond “not even wrong”.
It is mind boggling that so many kinds of wrong were compressed into such a minor piece of guff and then sold to the world as “science”.

MarkW
Reply to  Raymond L. Blinn
September 26, 2015 7:38 am

I have some tree ash in my backyard, but I wasn’t able to get any tree ring data from it.

Duster
Reply to  Raymond L. Blinn
September 27, 2015 10:18 pm

You don’t need to cut them down. All you need is what is known in forestry as an increment borer. It takes a neat core of the tree. It does take some practice to accurately hit the heart of the trunk. Mann would clearly use the one that laid on the most growth most recently.

msbehavin'
September 25, 2015 1:37 pm

Lots of great refutation to Mann’s research upthread.
I went to the Union’s site and read the columns, but noticed no one appears to be able to comment on them. I’m a Californian, so it affects me personally.
Mann made several claims in his rebuttal,two of which we know to be patently and ridiculously false , especially the one about SKS. Heck, they’ve even deleted my comments there (haven’t even gone there for years, but they are how I found WUWT and so for that I’m grateful –smile) and I try my best to behave in a reasonable civil manner in public (even if I’m mostly anonymous) including online.
Perhaps this is an opportunity to make Mann put up or shut up in public.
As a “scientist” he needs to validate his claims of :”funding by the fossil fuel industry”, and “a website run by a scientist”, by providing the facts for all to read: Which specific “fossil fuel industries” are funding which specific scientists (including the ones on which smear campaigns have been attempted but unfounded)? Who exactly is the “scientist” that runs SKS and in what field does he hold advanced credentials?
He is the one who made reference to “talking points”. Lets call him out on his own propaganda.

msbehavin'
Reply to  msbehavin'
September 25, 2015 1:45 pm

PS I noticed he once again doesn’t address or debate the science at all, only makes his own usual propaganda talking points.

Rob Ricket
September 25, 2015 2:26 pm

Esper has long been a thorn in Mann’s side. Mann has on occasion attempted to bully him, but Esper has remained independent and resolute.

Gunga Din
September 25, 2015 2:48 pm

Mann “et al”‘s motto: “Any delusion to reach the desired conclusion”.
And as long as I’m treading on sueable ground, yet another replay of…
Stopping By Yamal One Snowy Evening
by Guess Who
What tree this is, I think I know.
It grew in Yamal some time ago.
Yamal 06 I’m placing here
In hopes a hockey stick will grow.
But McIntyre did think it queer
No tree, the stick did disappear!
Desparate measures I did take
To make that stick reappear.
There were some corings from a lake.
And other data I could bake.
I’ll tweak my model more until
Another hockey stick I’ll make!
I changed a line into a hill!
I can’t say how I was thrilled!
Then Climategate. I’m feeling ill.
Then Climategate. I’m feeling ill.

Jeff Alberts
Reply to  Gunga Din
September 25, 2015 6:53 pm

What does Yamal have to do with Mann?

mebbe
Reply to  Jeff Alberts
September 25, 2015 7:39 pm

Mann doesn’t care for Briffa and Briffa’s not fond of the Mann.
I hope you’ll volunteer to write a refresher course on the MBH98/ , Graybill/Idso series, Yamal single tree confusion.

Gunga Din
Reply to  Jeff Alberts
September 27, 2015 12:38 pm

An honest question: Yamal 06 had nothing to do with the Hockey Ring…er…Stick?

High Treason
September 25, 2015 3:12 pm

All the climate propaganda could perhaps be renamed “Goebbels warming.” All you have to do to bust the consensus myth is to look at the Cook et al “study” Of the 4,000 odd that offered an opinion from the 11,944 sample size, only 64(some suggest it is just 41) articles gave a qualified verdict that humans are the dominant cause of global warming/climate change. This is around 1%-this is a consensus?. Classifying those papers that used very much inconclusive terminology(weasel words-may, might, could) as positive evidence of a consensus is blatantly misleading. Real science is about qualified conclusions.
Do note, climate “action” can only make any sense if humans ARE the dominant cause of global warming/ climate change. If humans were say 50% of the “problem”, totally destroying humanity would only “fix” half the “problem.”

Neville
September 25, 2015 3:24 pm

Don’t forget that the Lloyd study looked at the last 80 centuries and found nothing unusual or unprecedented about our slight recent warming. In fact he found about an average 1 C deviation per century.
Our warming comes after the end of one of the coldest periods of the last 10,000 years, called the LIA. And the HAD 4 data only shows about 0.8 C since 1850. They’ve been conning us for over 30 years.
Here’s Lloyd’s abstract————-
.O.Box 652 Cape Town 8000 lloydp@cput.ac.za
ABSTRACT
There has been widespread investigation of the drivers of changes in global
temperatures. However, there has been remarkably little consideration of the
magnitude of the changes to be expected over a period of a few decades or even a
century. To address this question, the Holocene records up to 8000 years before
present, from several ice cores were examined. The differences in temperatures
between all records which are approximately a century apart were determined, after
any trends in the data had been removed. The differences were close to normally
distributed. The average standard deviation of temperature was 0.98 ± 0.27
o
C.
This suggests that while some portion of the temperature change observed in the
20th century was probably caused by greenhouse gases, there is a strong likelihood
that the major portion was due to natural variations.
And here’s the study———— http://www.researchgate.net/publication/276276180_An_Estimate_of_The_Centennial_Variability_of_Global_Temperatures

George Devries Klein, PhD, PD, FGSA
September 25, 2015 3:47 pm

Please notice the Alinsky-type response Mann made to Sauer.

Gary H
September 25, 2015 4:15 pm

Too much fun:
“As a consequence, earlier warm periods during the late 14th and 15th centuries appear warmer,
though not statistically significant, compared to the late 20th century.”
We already understand that the the era centered on the MWP (9th -11th centuries) were as warm, or warmer than today. Adding a few hundred additional years to the warm period lends in understanding how forests w/ mature trees were growing in the then future path of the Mendenhall and Exit Glaciers up in Alaska, only to be be buried under the ice as it did advance, and now to be revealed once again, as this naturally occurring warm cycle is just getting under way.
May the wonderful warmth continue.

Lady Gaiagaia
Reply to  Gary H
September 25, 2015 4:30 pm

Temperatures remained higher than now into the 14th century. They deteriorated through the 15th and 16th centuries (Spoerer Minimum), hitting bottom in the depths of the LIA in the 17th century (Maunder Minimum). There was improvement for part of the 18th century, but the LIA cooled again during the early 19th century (Dalton Minimum).

Gary H
Reply to  Lady Gaiagaia
September 25, 2015 5:30 pm

That’s about the way I see it as well. (;~>

John Herron
September 25, 2015 4:21 pm

From the shadows.
Rather ask yourself why in the world , the expert global panic guy would be so worried by an op-ed piece in a ‘chuck wagon’ (my own opinion because I consider my own county paper the squares villi screamer ) paper op-ed piece he felt that he had to slam down on this?

Alx
September 25, 2015 6:37 pm

baseless talking points that have their origin in fossil-fuel industry-funded climate change denial propaganda

That’s all that Manns got? The man has gone beyond pathos into tragedy. Is he worthy of pity now?
Nah.

September 25, 2015 7:51 pm

Leaving aside whether it’s appropriate to take a study of one area as a refutation of Mann’s work which claimed to reconstruct temperature of the entire northern hemisphere, how are you guys not bothered by the fact pretty much the entirety of this reconstruction is adjusted? The first 800 years or so of it gets adjusted:

The removal of δ13C level differences and age-trends
resulted in a millennium-long record indicating higher
chronology levels back in time, compared to its non
detrended “raw” counterpart (Fig. 2). The detrending
procedure corrected the systematically lower δ13C values
of biologically younger rings likely triggered by the (i)
uptake of CO2 enriched ambient air from soil respiration
(Francey and Farquhar, 1982), and (ii) decreased hydraulic
resistances and higher stomatal conductance of smaller
trees (McDowell et al., 2002). As a consequence, the
residual timeseries, between the raw and detrended chronologies,
increases from –0.26°C in the 17th century to
–0.74°C in the 13th century.

Then the everything after 1850 gets adjusted:

A major constraint of the new reconstruction is the
substantial difference in recent temperature trends caused
by post-1850 δ13C correction procedures. The correction
applied here, accounting for atmospheric 13C/12C ratio
and plant physiological effects, appeared most suitable as
it produced a timeseries without any trend in residuals
after regressing against instrumental temperatures. However,
developing objective criteria for post-1850 correction,
independent of the goodness of fit with instrumental
target data, are needed to establish δ13C based reconstructions
as an additional proxy for studying climate variations
over past millennia.”

The authors themselves even caution that the adjustments may not be right:

Our new δ13C based reconstruction seems to capture
20th century temperature trends better than the existing
MXD records. The performance improvement is largely
determined by the applied atmospheric CO2 correction.
We considered the Kur, Fen, and Atm corrections in our
reconstruction attempts, choosing the annually resolved
reconstruction containing the least trend in residuals after
calibration against instrumental summer temperatures
(–0.01°C/decade for Kur, +0.06°C/decade for Fen, and
–0.10°/decade for Atm; Fig. 6). However, the decision to
favor one δ13C correction scheme over another is generally
not well justified (Treydte et al., 2009), and perhaps
represents the most significant constraint of the new
summer temperature reconstruction presented here.

When temperature station records get adjusted, people throw fits claiming it is no longer “data.” When these guys adjust their data, everyone gets excited and labels it “facts” and “hard science.” Whats up with that?

Reply to  Brandon Shollenberger
September 25, 2015 8:58 pm

brandon…
EWhen glaciers recede, and reveal corpses, mining tools, trees and the like, what is one to make of it?
Many would conclude that tress and mines and people were there before the glaciers advanced..what is your conclusion?
the people dug holes in the ice and dropped their tools, mined the earth and dragged trees into the ice? really?

MarkW
Reply to  davideisenstadt
September 26, 2015 7:42 am

Not just trees, but fairly sizeable trees. Ones that would take decades at a minimum to reach such size.

Alan Robertson
Reply to  Brandon Shollenberger
September 25, 2015 10:44 pm

Brandon,
Sometimes, data adjustments could be likened to brushing the hair out of one’s eyes. But some adjustments have been wielded as a tool, conveying a rendered truth as if seen by a blindfolded man, facing a window with curtains drawn.

Reply to  Alan Robertson
September 26, 2015 6:27 am

Alan Robertson:

Brandon,
Sometimes, data adjustments could be likened to brushing the hair out of one’s eyes. But some adjustments have been wielded as a tool, conveying a rendered truth as if seen by a blindfolded man, facing a window with curtains drawn.

And remarkably, the distinction seems to always be whether or not one likes the results which arise from the adjustments. Amazing how that happens, no?

Alan Robertson
Reply to  Alan Robertson
September 26, 2015 6:56 am

Brandon Shollenberger,

And remarkably, the distinction seems to always be whether or not one likes the results which arise from the adjustments. Amazing how that happens, no?

Your conjecture has merit, but only in narrow regard. Manipulation of data to return a result which satisfies an agenda is purposeful lying.

Menicholas
Reply to  Alan Robertson
September 27, 2015 12:21 am

“And remarkably, the distinction seems to always be whether or not one likes the results which arise from the adjustments. Amazing how that happens, no?”
And coincidentally, the people doing the adjusting always get exactly the result that they like, don’t they?
The result, by the way, that just happens to back up the story they are pushing.
You are wrong, though.
It is not in the slightest bit amazing.
It is 100% predictable.
Isn’t it?

knr
Reply to  Brandon Shollenberger
September 26, 2015 2:32 am

‘Mann’s work which claimed to reconstruct temperature of the entire northern hemisphere’ but in pratice only covered a very small part of it , although that has never stopped Mann’s supporters from claiming it is ‘valid ‘ for the whole planet .
When Mann ‘claims ‘ it is always best to be carrying salt with you.

Taylor Pohlman
Reply to  Brandon Shollenberger
September 26, 2015 5:29 am

Nobody is claiming the tree-derived temperatures are “data”, Brandon. But when you have a highly calibrated instrument measuring the exact quantities under consideration (I.e. Temperature by a thermometer) then it’s a bit different to say “that guy back in 1938 didn’t know what he was doing, so I’ll simply lower his measurement until I get a result that fits my thesis”

Reply to  Taylor Pohlman
September 26, 2015 6:26 am

Taylor Pohlman:

Nobody is claiming the tree-derived temperatures are “data”, Brandon.

Um, this post explicitly says things like:

What I find most interesting is their graph showing how they calibrated the δ13C data against the instrumental temperature record.

So clearly, the adjusted values are being labeled data like I said. The only quibble you can raise is that the “temperatures” derived from tree rings aren’t being labeled data, but I never claimed they were. I said the authors results, which depend entirely upon adjustments, are being promoted as good with their “data” being accepted despite the massive amounts of adjustments it undergoes.

But when you have a highly calibrated instrument measuring the exact quantities under consideration (I.e. Temperature by a thermometer) then it’s a bit different to say “that guy back in 1938 didn’t know what he was doing, so I’ll simply lower his measurement until I get a result that fits my thesis”

That’s not the rationale for any of the adjustments. If you think that’s a fair characterization of the reasoning behind any adjustment to temperature data, you have no idea what you’re talking about. If you’re just intentionally misstating the case to paint people as doing inappropriate things you know they don’t do, you’re being dishonest. Either way, your comment is pretty bad.

September 25, 2015 9:15 pm

The graphs shown in the above article look awfully noisy, with low correlation to every version of every version of GISS and NCDC (even as of 2008 and most curves significantly differ from GISS/NCDC versions of around 2000), every version of HadCRUT (even the satellite-TLT-correlating champion Hadcrut3 and the older HadCRUT2), even paleoclimate composites that rightwingers like such as sometimes Moeberg and especially Loehle. Also, usage of JJA without mention of full-year figures gets me quick to suspect cherrypicking.

ulriclyons
September 26, 2015 2:47 am

Did anyone else spot that Esper shows the Maunder Minimum to be very warm?

MarkW
September 26, 2015 7:24 am

“I wonder if Mann’s Bristlecone Pine tree core samples from MBH98 still survive”
If they do, they won’t for long.

September 26, 2015 8:18 am

d13C in the old xylem we call wood seems a very dubious proxy for temperature. The xylem carries water and nutrients up from the ground. Are you measuring the 13C from the roots? Is the notion that 13carbohydrate produced by photosynthesis and dispersed by the phloem shows up in the current year xylem? Or was that last year’s stored in the roots.

Tim
September 26, 2015 8:46 am

Speaking as a layman, if there can be no way of accurate computer measurement of global cloud/water vapor and there is no inclusion of sunspot activity in these hypotheses – what are we all talking about?
Please convince me in a good old Occam’s razor way. Like the majority of the world’s governments are apparently being convinced.

NancyG22
September 26, 2015 8:47 am

I posted a comment on Mann’s facebook page under his post regarding that article. I bet it gets deleted.
“Dr. Mann, you stated that Skeptical Science is a scientist run site. Would you please tell us the name of the scientist that runs that site? Also, what is his field of expertise?”

Tim
Reply to  NancyG22
September 26, 2015 9:02 am

Nancy, it appears to be a “protected species” site.Why is it not accountable for its name, as was this site:
http://www.qt.com.au/news/australian-vaccination-skeptics-network/2195295/

September 26, 2015 1:25 pm

With all this talk of reconstructions, I did want to make a joke about my desire to “reconstruct” somebody’s face.
But, unfortunately the object of my joke appears already to be an eager litigant with zero sense of humour.

Gary Pearse
September 26, 2015 2:24 pm

Proxy also captures temp fiddling, notably the year before satellite record started – temp is pushed down to give a steeper upslope. I think a corrected instrument record would give a better R#2 factor. It would be worthwhile to do a number of similar tests to verify the instrument record is systematically fiddled as we can be sure it has been.

JImmi_the_dalek
September 26, 2015 3:12 pm

This is a local record. If you want to take it as representative of a global record then you have dug yourselves a trap and then fallen into it. If this were a global record, you would have just eliminated the LIA as a global phenomenon. You don’t really want to do that, do you?

Reply to  JImmi_the_dalek
September 27, 2015 5:20 am

Repeat after me, in a hoarse Dalek-like monotone “This post is about a paper analysing tree proxies for temperature in the Spanish Pyrenees”. Global temperature isn’t mentioned at all. You’re as bad as Sou at HotWhopper misrepresenting what this post is about. Open your eyes and engage your brain.
http://blog.hotwhopper.com/2015/09/different-versions-of-surface.html

JImmi_the_dalek
Reply to  Tony Price
September 27, 2015 2:03 pm

Tony
Your admonition should be directed against the majority of other correspondents here who, apart from a few, quite clearly think this paper is about about Mann and the hockey stick. No doubt they are taking their cues from the introduction. If the article had simply quoted the title and abstract from Esper’s paper and said “ Here is a paper about the Pyrenees which tells you nothing about the validity or otherwise of the HS” would the comments have been the same?

Reply to  Tony Price
September 28, 2015 12:11 am

The comments are irrelevant. You were commenting on the post, I was summarising the post. If commenters can’t understand plain english, as possibly you have difficulty with, I can’t help you.

JImmi_The_dalek
Reply to  Tony Price
September 28, 2015 1:12 am

Tony,
So you agree that my comments were correct and those of other commentators were , in your words, irrelevant. I am sure they appreciate that.

Toto
September 27, 2015 9:28 am

Mann is the Hockey Team’s enforcer. Enforcers are also known as “goons”. You might be interested in Conrad Black’s response to Mann’s vicious tweet responding to a mere mention of Mann in one of his articles. Mann is not only a disgrace to his profession (see Steyn’s book), he is also a disgrace to the human race.
http://news.nationalpost.com/full-comment/conrad-black-on-climate-alarmists-and-other-discarded-relics

Barbara Rumsey
September 27, 2015 1:32 pm

I know little of science and have even less understanding, but great admiration for, all of you knowledgeable writers. Even so, there is a place for such as I on this site since I have followed Mark Steyn’s remarkable fortitude and patience in this important battle. So on a lighter note and with little intellectual credentials, I offer this:
With wit and elan
Steyn comments to Mann
In a word your hockey stick sucks
What’s next you boob
A graffic to prove
The circumference of tree-ring pucks?

Joel Arbic
September 28, 2015 1:47 pm

I’ll be the antagonist, although I know I will get a lot of negativity. Climate change is real, humans are contributing, and we are going to see big changes in the near future. It’s already happening. I have a cousin who does mass farming in Oklahoma and would not be considered a liberal at all. She was recently telling me how massive the changes have been in the last 10 years. When you can plant your crops, what crops you can grow, how much they will yield. These are the people on the ground that really see the effects. Most of us are spending our time in climate controlled buildings and don’t realize that the extra rain, longer springs, droughts, etc are very REAL for people that depend on predicable weather cycles.

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