Present warming is extraordinary
POTSDAM INSTITUTE FOR CLIMATE IMPACT RESEARCH (PIK)
“Was there a warm period in the Middle Ages that at least comes close to today’s? Answers to such fundamental questions are largely sought from tree ring data,” explains lead author Josef Ludescher of the Potsdam Institute for Climate Impact Research (PIK). “Our study now shows that previous climate analyses from tree ring data significantly overestimate the climate’s persistence. A warm year is indeed followed by another warm rather than a cool year, but not as long and strongly as tree rings would initially suggest. If the persistence tendency is correctly taken into account, the current warming of Europe appears even more exceptional than previously assumed.”
To examine the quality of temperature series obtained from tree rings, Josef Ludescher and Hans Joachim Schellnhuber (PIK) as well as Armin Bunde (Justus-Liebig-University Giessen) and Ulf Büntgen (Cambridge University) focused on Central Europe. Main reason for this approach was the existing long observation series dating back to the middle of the 18th century to compare with the tree ring data. In addition, there are archives that accurately recorded the beginning of grape and grain harvests and even go back to the 14th century. These records, as well as the width of tree rings, allow temperature reconstructions. A warm summer is indicated by a wide tree ring and an early start of the harvest, a cold summer by a narrow tree ring and a late start of the harvest. The trees studied are those from altitudes where temperature has a strong influence on growth and where there is enough water for growth even in warm years.
“Medieval archives confirm modern climate system research”
“It turned out that in the tree ring data the climatic fluctuations are exaggerated. In contrast, the temperatures from the harvest records have the same persistence tendency as observation data and also the computer simulations we do with climate models,” says co-author Hans Joachim Schellnhuber of PIK. “Interestingly, medieval archives thus confirm modern climate system research.”
To eliminate the inaccuracies of the tree ring data, the scientists used a mathematical method to adjust the strength of the persistence tendency to the harvest data and the observation data. “The adjustment does not change the chronological position of the respective cold and warm periods within the tree rings, but their intensity is reduced,” explains co-author Armin Bunde from the University of Gießen. “The corrected temperature series corresponds much better with the existing observations and harvest chronicles. In its entirety the data suggests that the medieval climate fluctuations and especially the warm periods were much less pronounced than previously assumed. So the present human-made warming stands out even more.”
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Article: Josef Ludescher, Armin Bunde, Ulf Büntgen und Hans Joachim Schellnhuber (2020): Setting the tree-ring record straight. Climate Dynamics, DOI: https://doi.org/10.1007/s00382-020-05433-w
Weblink to article: https://link.springer.com/article/10.1007/s00382-020-05433-w
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Quote from the article.
“If the persistence tendency is correctly taken into account, the current warming of Europe appears even more exceptional than previously assumed.”
Well they could just have come right out and said ” It is worse than we thought”
Perhaps the “new information” about climate in past periods derived from tree rings, will also explain how farming used to be carried out successfully on Greenland, but not now as it is too cold to do so, Perhaps it will reveal why, wine production was widely available in England during the earlier warm periods, but today that opportunity is limited to just a few places with high risk of zero production years.
As Prince Charles is a self proclaimed expert at listening to the trees, perhaps we should ask him what they are telling him at the moment?
Prince Charles is busy, having reincarnated into a mortal virus capable of killing millons, like he expressed that was his secret wish.
Actually that was his father Prince Philip who has that permanent anti human wish.
I suspect there are some paternal influences in play, but talking to the plants is a peculiar habit of Charles. Well, it’s what he does when he is not wishing to be a tampon anyway….
The day barley ripens again in Greenland, like it did in the MWP, then it will be as warm as it was then.
It might actually happen. On Iceland barley growing was resumed in the warm 1930’s after a 300+ year hiatus.
I suspect modern variations are hardier than those available 300 years ago.
Yes, it is a new Hockey Stick trick stated directly in the paper title “Setting the tree-ring record straight” . And flatten it they did, specifically to lower four warm bumps comparable to present temps.
My synopsis: https://rclutz.wordpress.com/2020/09/10/potsdam-does-a-new-hockey-stick-trick/
“We have to get rid of the medieval warm period”
“I get the sense that I’m not the only one who would like to deal a mortal blow to the misuse of supposed warm period terms and myths in the literature. ”
https://wattsupwiththat.com/2013/12/08/the-truth-about-we-have-to-get-rid-of-the-medieval-warm-period/
“The corrected temperature series corresponds much better with the existing observations and harvest chronicles. In its entirety the data suggests that the medieval climate fluctuations and especially the warm periods were much less pronounced than previously assumed. So the present human-made warming stands out even more.”
In Finlands northern part Lappland have whole medieval oaks in svamps. Now oak grows only in the most southern part, about 1000 kilometers from Lappland. And this is observation, so obviously Josef Ludescher of the Potsdam Institute for Climate Impact Research is wrong.
I wonder if the great rush to biomass is purely to get rid of the evidence by burning it.
Although we are not officially in a period as warm as the MWP we seem to be using Mediaeval means for predicting the climate….Michael Mann’s tree ring readings have cost us, and are still costing us a lot in terms of mitigating climate change. Reading the entrails in the Wuhan Lab has and is costing us a lot in terms of life/death and the economy…and now I hear it is also a climate change indicator. Both these “technologies” are ruinous and I suggest we stop them at once and let the climate do its own thing as it always has done.
“We apply a low-pass filter to the time-series data, because of a dubious construct we call persistence. Lo and behold, the range is compressed. This proves AGW is even worse than we thought.”
Tautological, circular numeric masturbation.
I see Greg Goodman beat me to the punch.
I’ve cored a lot of trees and compared ring widths to climate data. What showed up consistently was that precipitation probably plays a bigger role than temperature in ring width. In general, I found a poor correlation of ring width with temperature. In fact, cool periods with higher precipitation sometimes showed wider rings than warm, dry periods, especially in arid climates. The Chinese seem to have gotten good results with tree rings confirmed by other methods. My conclusion about all this is that tree rings sometimes track temperature and sometimes they don’t.
I have read through all the post and see no mention there or in the original story about some trees rotating ass they grow. Some may make more than a complete 360 degree rotation, depending on conditions and their particular location.
In the early 1950’s, my father had a saw mill he could move from location to location to turn smaller forests into lumber. Sometimes he would discover a log from such a tree and it would be removed from the mill and discarded. The lumber would not be usable for anything.
Today we can occasionally find a very old ponderosa pine tree that has died and lost all it’s bark and will show how it turned over it’s lifetime. We can also find the remains of such trees on the ground here in Central Oregon.
I wonder if the study of tree rings based on tree stumps ever account for that tree turning as it grew?
Paul in Central Oregon
So much for dildoclimatology.
The Tree ring history of Glacier Bay Alaska is used to record the number of growing years between glaciers. And since receding Glaciers in this decade uncovered stumps of trees that were several hundred years old wen the trees above were snapped off, then it is save to say it was warmer then this decade for hundreds of years. And that happened 6 times in the last ten thousand year. Nothing any one says for climate alarmist verbiage is worth listening too. There are cycles to warming and cooling. Try a 1500 year cycle (10,000 / 6). We are little people living a very short time. yes it warms between ice ages duh.
https://www.nps.gov/articles/historicglacieractivityinglacierbay.htm
The Medieval Warm Period has been firmly established around the world by not just tree ring data but by glacier retreat, lake sediments, temperature dependent biota, oxygen isotopes, deuterium excess, ice rafted debris, and other means.
https://www.google.com/maps/d/viewer?mid=1akI_yGSUlO_qEvrmrIYv9kHknq4&ll=-1.6538884343610288e-13%2C38.03818700000005&z=1
Not just that, but the MWP has been historically recorded in written records.
It’s flat dishonest of the authors to suggest that this tree ring study makes the MWP less of a real thing.
Of hundreds of WUWT comments sections I’ve read, this is a favorite. Thank you all.
(Confirmed my own tree ring observations as a kid in western Montana. Should never have doubted my young logic.)
Climate Impact Research Institute. Motto: Carbo Carbonis Dioxidenus Malus. Patron saint: St. Alexandria de Occassio-Cortez
Analyses of ice glaciers Length are more reliable than tree rings !
Why Publishing such fake News ?
From the article: “The corrected temperature series corresponds much better with the existing observations and harvest chronicles. In its entirety the data suggests that the medieval climate fluctuations and especially the warm periods were much less pronounced than previously assumed. So the present human-made warming stands out even more.”
Well, first of all, there is no evidence of any “human-made warming” in connection with the Earth’s atmosphere, and second of all, we don’t need to use tree rings to show it was just as warm in the past, when CO2 was a minor player, as it is today, when CO2 has increased in the atmosphere.
All we have to do is look at regional Tmax charts from around the world to see that it was as warm or warmer in the Early Twentieth Century as compared to today. We have actual temperature charts recorded by human beings that demonstrate this. We don’t need tree rings.
Regional Tmax temperature charts destroy the Human-caused Climate Change narrative. That’s why you never hear alarmists referencing them. But they’re out there.
Tmax charts
US chart:
China chart:
India chart:
Norway chart:
Australia chart: