Continuing Problems with Paleoclimate Proxies

lols! Says the person bringing up a 12 year old “scandal” that went through multiple investigations and showed no wrong doing

https://www.theguardian.com/theobse...gate-10-years-on-what-lessons-have-we-learned

 

Indeed.
"Generally speaking, we can observe that the scientists in any particular institutional and political setting move as a flock, reserving their controversies and particular originalities for matters that do not call into question the fundamental system of biases they share."
—Gunnar Myrdal, Objectivity in Social Research

 

Ummmmm Would you call this a “recent publication”



And he was not even a freaking scientist OR a psychologist or a sociologist! Your cherry picked phrase is unclear as to who he is talking about but suggests, given the title that he is referring to sociology rather than physics and chemistry

 

Economist, sociologist, Nobel laureate. I hope you're not going to descend into know-nothingism.
Myrdal made a powerful point aptly illustrated by climatologists' circling the wagons in response to Climategate.

 

When I googled his achievements it just said “economist” so I would appreciate if you linked to more information but again let us look at WHEN this was published to realise it is ONE out of context phrase apropos of nothing

He was not talking of climate scientists because it predates the main controversies in climate science. No this is the intellectual equivalent of throwing mud at a wall and hoping it sticks

in fact your very paper you just linked to in post 107 belies “group think”

 

Hmmm. This is the very first entry under his name.

Karl Gunnar Myrdal (/ˈmɜːrdɑːl, ˈmɪər-/ MUR-dahl, MEER-; Swedish: [ˈɡɵ̌nːar ˈmy̌ːɖɑːl]; 6 December 1898 – 17 May 1987) was a Swedish economist and sociologist. In 1974, he received the Nobel Memorial Prize in Economic Sciences along with Friedrich Hayek for "their pioneering work in the theory of money and economic fluctuations and for their penetrating analysis of the interdependence of economic, social and institutional phenomena."[2] When his wife, Alva Myrdal, received the Nobel Peace Prize in 1982, they became the fourth ever married couple to have won Nobel Prizes, and the first to win independent of each other (versus a shared Nobel Prize by scientist spouses). He is best known in the United States for his study of race relations, which culminated in his book An American Dilemma: The Negro Problem and Modern Democracy. The study was influential in the 1954 landmark U.S. Supreme Court Decision Brown v. Board of Education. In Sweden, his work and political influence were important to the establishment of the Folkhemmet and the welfare state. Myrdal and his wife advocated for social engineering.
Gunnar Myrdal - Wikipedia
https://en.wikipedia.org › wiki › Gunnar_Myrdal

Gunnar Myrdal became the Executive Secretary of the United Nations Economic Commission for Europe in 1947. During his tenure, he founded one of the leading ...

It's amusing to see you allege "groupthink" in a paper with two authors who reside in different countries.
Myrdal's point is universally applicable to human endeavors.

 

Sigh! Read my post again or look up the word “belies”
and it is an allegation - some disgruntled old economists view of a group of ? Sociologists from the sixties - before there was even much research on “group think”

And again I will aver (means state) that your paper posted in post 107 shows THERE IS NO GROUP THINK

 

Apparently you did not actually read the paper. Last sentence: "Climate science would benefit from more diversification in the important field of T2k composites." It's target is groupthink.
As for Myrdal, you're free to criticize him, but I'll take his view over yours.
And yes, I misread "belies" as "betrays." My bad.

 

That is baldly false. All the multiple "investigations" (conducted, not coincidentally, by friends of those being investigated) established was plausible deniability of certain specific forms of academic malfeasance.

 

Geeeze they must have an awful lot of friends if all those investigations found there to be no basis for concern

 

They circled the wagons to protect their own.

 

That's not what they found. What they found was no basis for them to be concerned. Big difference.

 

Proof??

Or just a convenient excuse to dismiss all those investigations that found no wrongdoing

 

They merely defined wrongdoing such as to find none.

 

Which tree rings to believe?
Follow the Science: But Which Results? Using Same Tree Ring Dataset, 15 Groups Come Up With 15 Different Reconstructions
By P Gosselin on 19. April 2022

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A 2021 study appearing in Nature Communications by Buentgen et al reports on the results of a double-blind experiment of 15 different groups that yielded 15 different Northern Hemisphere summer temperature reconstructions. Each group used the same network of regional tree-ring width datasets. . . .

 

And none of them matters because tree growth depends on CO2 as well as temperature. So tree-ring reconstructions that are purported to show rapid warming since the mid-19th century may just be recording increased CO2. This means tree-ring records can't reliably be calibrated against the instrumental temperature record, and tree rings are consequently the very last proxy anyone should be using to compare modern and ancient temperatures.

 

Nic Lewis has already compelled one retraction by Nature. Here he takes aim at another paper.
Osman et al. 2021: a Flawed Nature Paleoclimate Paper?
Guest Blogger
In my view, Osman 2021’s preprint proxy-only reconstruction appears credible, although a lower SST multiplier than they used is appropriate. . . .
I do not consider Osman 2021’s main LGMR, data-assimilation reconstruction, which estimates 6.8°C mean LGM cooling, to be reliable. It is highly dependent on the spatiotemporal accuracy of LGM simulations by a single GCM. The external validation tests, when analysed properly, show no significant skill by either the model simulation prior or the LGMR posterior in predicting observed LGM changes in independent cave speleothem records. Moreover, those tests show that both the model prior and the LGMR posterior substantially overestimate observed LGM changes per independent ice core records. While the LGMR reconstruction is innovative, I am doubtful that the accuracy of model simulations and the spatial coverage and accuracy of proxy data over the period extending back to the LGM are adequate for a data-assimilation approach to give unbiased GMAT estimates. In my view, the method employed by Annan and Hargreaves (2013)[28], which scales model-simulation cooling patterns to best match proxy data (giving an estimate of 4.0°C LGM cooling in their case), is more suitable.

In my view, Osman 2021’s preprint proxy-only reconstruction appears credible, although a lower SST multiplier than they used is appropriate. I consider it to be more credible than the version of their proxy-only reconstruction published in Nature, as no explanation was given for that being different from the reconstruction in their preprint, and it matches the shape of the de facto preexisting standard SMC reconstruction time series less well than the preprint version. Using a multiplier based on the mean from the most recent, PMIP4 models, estimated average LGM GMAT was ~4.6°C cooler than preindustrial per the preprint proxy-only reconstruction. If, unlike in GCMs, SST actually changes as much as marine air temperature, as assessed by the IPCC in AR6, then the implied GMAT cooling would instead be ~4.3°C.

Nicholas Lewis April 2022

Addendum

Since writing this article a new Holocene study, Thompson et al. (2022), has been published in Science Advances (open access). Using the same GCM as Osman 2021, it shows that adding forest cover in the Sahara and mid-latitudes (partial at 3 kyr BP) and (except at 3 kyr BP) in the Arctic, to match pollen records substantially increases simulated GMAT at 3, 6 and 9 kyr BP. The difference at 6 kyr BP is 0.72°C, with the resulting GMAT being well above the preindustrial level. Osman 2021’s simulations incorporated this greening only partially.[29] Even with all these regions greened, the model simulation (prior) 6 kyr BP GMAT was still well below that of the Osman 2021 proxy-only reconstruction. These facts suggest that Osman 2021’s model prior may be particularly unsatisfactory, spatially as well in the global mean, during the Holocene.

 

From the very way back machine.
Global Warming Spawned the Age of Reptiles
Charles Rotter
Harvard researchers find rapid evolution of reptiles was triggered by nearly 60 million years of global warming and climate change . . . .

 

Steven McIntyre strikes again.
Steven McIntyre vs. the Spawn of Yamal
Charles Rotter
Stephen McIntyre’s tweet thread is a delight for old timers of the Climate Wars and has resurrected the issue, or at least the region, of the Enchanted Larch of Yamal.

For those who wish to catch up or refresh themselves, here is the post that launched a lot of hilarity and unadmitted embarrassment for the Climate Consensus Community.

YAD06 – the Most Influential Tree in the World
If you want to see a bevy of posts on this subject use this search string in your favorite search engine.

enchanted larch of yamal site:climateaudit.org
And here is the current Twitter thread.

Originally tweeted by Stephen McIntyre (@ClimateAudit) on August 30, 2022. . . . .

 

This field of inquiry seems to have lost their way.

The Last 12,000 Years Show a More Complex Climate History Than Previously Thought
Charles Rotter
Inconsistencies between Holocene climate reconstructions and numerical model simulations question the robustness of climate models and proxy temperature records.


New Open Access Paper published.

Here is the Abstract and Introduction. The paper is not paywalled.

Complex spatio-temporal structure of the Holocene Thermal Maximum

• Olivier Cartapanis,
• Lukas Jonkers,
• Paola Moffa-Sanchez,
• Samuel L. Jaccard &
• Anne de Vernal

Nature Communications volume 13, Article number: 5662 (2022) Cite this article

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Abstract
Inconsistencies between Holocene climate reconstructions and numerical model simulations question the robustness of climate models and proxy temperature records. Climate reconstructions suggest an early-middle Holocene Thermal Maximum (HTM) followed by gradual cooling, whereas climate models indicate continuous warming. This discrepancy either implies seasonal biases in proxy-based climate reconstructions, or that the climate model sensitivity to forcings and feedbacks needs to be reevaluated. Here, we analyze a global database of Holocene paleotemperature records to investigate the spatiotemporal structure of the HTM. Continental proxy records at mid and high latitudes of the Northern Hemisphere portray a “classic” HTM (8–4 ka). In contrast, marine proxy records from the same latitudes reveal an earlier HTM (11–7ka), while a clear temperature anomaly is missing in the tropics. The results indicate a heterogeneous response to climate forcing and highlight the lack of globally synchronous HTM.

 

Because the anti-fossil-fuel hysteria mongers are trying to get to a place that isn't there.

 

Not paleoclimate, but still interesting.

• “Paleontologist accused of faking data in dino-killing asteroid paper.” He “denies claims he made up data to scoop a former collaborator.”

 

Warmth Limits For Tree Growth Affirm Austria Was 4-7°C Warmer Than Today 2000 Years Ago
By Kenneth Richard on 23. January 2023

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Robust evidence from bison remains recovered from the Austrian Alps in 2020 and 2021 invalidate claims modern Alpine temperatures are unusually warm.
A new study suggests that from about 6000 to 1200 years ago European bison fed on deciduous tree/vegetation that grew at Alpine altitudes reaching around 800 m higher than they do today.

Known beech and oak tree growth warmth thresholds – the required number of days per year above a minimum temperature limit – thus affirm Austria needed to be 4-7°C warmer than now during this period (~2000 years ago).

“[T]he beech limit but also the forest line during the »wisent time« (6,000 to 1,200 years before today) was much higher and the average summer temperature had to be at least 3 to 6 °C higher than today. Remarkable is a palynological record (Ressl, 1980) from the shaft cave Stainzerkogelschaft near Lunz am See. Remains of wisent were found in the shaft (1,463 m, see Tab. 3). The clay with a skull fragment with horncores inside was examined palynologically. The dominating pollen were from alder (Alnus), oak (Quercus) and linden tree (Tilia). The oak boundary (boundary between colline and montane vegetation stages) today lies between 400 and 800 metres in the Northern Alpine Alps (Grabherr et al., 2004). Oaks (Quercus) at an altitude of 1,450 metres around 2,000 years ago also indicate a climate approximately 4 to 7 °C warmer than today.”


Image Source: Schaer et al., 2022
. . . .

 

"But that was only in Austria and all the other places we have credible data for. Everywhere else, it was freezing!" -- CO2-centered climate "science"

 

Do European tree ring analyses indicate unusual recent hydroclimate?
Posted on February 21, 2023 by curryja | 5 comments
by Frank Bosse and Nic Lewis

Not really.

Continue reading →
. . . .
Conclusion

MBF23 is a very valuable paper when it comes to the description of the variability of European summer droughts since 1600. However, neither its title “European tree-ring isotopes indicate unusual recent hydroclimate” nor the claim in its Abstract that “recent European summer drought (2015–201 is highly unusual in a multi-century context” are justified by the data used in the paper.

The lower resolution in time and spatially of the reconstruction before 1950 in relation to the determined SPEI after 1950 casts some doubts if the comparison of some years after 1950 to the historical reconstructed values is appropriate.

MBF23 should be corrected and retitled because some key conclusions, including the headline claim in its title, are not supported by proper statistical analysis of the SPEI values that their reconstruction method produces. The recent European drought to 2018 remained within the range of natural variability.