By P Gosselin on 19. April 2022
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.
Hat-tip: Klimaschau 108
What’s fascinating is that all groups, though using the same data network, came up with a different result. When it comes to deriving temperatures from tree-rings, it has much to do with individual approach and interpretation. Sure we can follow the science, but whose results?
The 15 groups (referred to as R1–R15) were challenged with the same task of developing the most reliable NH summer temperature reconstruction for the Common Era from nine high-elevation/high-latitude TRW datasets (Fig. 1):
Cropped from Figure 1, Buentgen et al
The 15 groups who contributed independently to this experiment all had experience in developing tree ring-based climate reconstructions. But as the study describes, each group employed a distinct reconstruction approach. In summary, the results ranged by as much as 1°C.
How could the groups come up with different results?
The paper’s abstract summarizes: “Differing in their mean, variance, amplitude, sensitivity, and persistence, the ensemble members demonstrate the influence of subjectivity in the reconstruction process. We therefore recommend the routine use of ensemble reconstruction approaches to provide a more consensual picture of past climate variability.”
This should not surprise since tree ring width does not correlate to temperature. Botanists, horticulturists, foresters, paleobotanists have been saying this for 30 years but “climate scientists” refuse to listen.
They listen but they are paid not to understand.
They seem like fortune tellers who can predict anything you want if you cross their palm with silver.
Gold
“Silver” is often used because of it adds the concept of betrayal, or ulterior motive.
The past climate appears to be as variable as the number of groups you have studying it and their results dependent on which way you MASH the data
Mikey Mann obviously chose to look at Briffas database with Both Eyes Closed
You can always tell “climate scientists”, but you just can’t tell them much.
Tom, you have hit the nail directly on the head.
Tree rings work well when it comes to dating, and reasonably well when it comes to moisture in a given year.
But temperature?
Which temperature?
Daily highs?
Daily lows?
Daily high in Summer?
What about daily high in Winter and Spring?
Or maybe they mean monthly means?
How would that work?
And if they are talking about the yearly mean deviation from average, IOW “anomalies”, then it says about nothing that could possibly correlate with what makes trees grow more in a year.
From the abstract….. “We therefore recommend the routine use of ensemble reconstruction approaches to provide a more consensual picture of past climate variability.”
If I read this correctly, they are advocating that the truth lies in looking at all the model outcomes and then what, take an average?
What if all the models are wrong?
What do you mean .. “what if”
How can a glorified computer game be “wrong”.
The outcome depends solely on the players.
I vote we use Mikey Mann’s Hocky Team results. That will get us the largest grants from the politicized Deep State.
At best, only one can be right.
They are all right, because all of them are within the same margin of error: about 5c, of course they won’t admit that is their actual margin of error.
And that margin of error is so great that it makes their models meaning less, given that the Earth’s temperature has never varied (as much as we can tell) by more than +/-8 degC in over 500 million years.
Since they’re all different there are only two possibilities: 1) one is right and all the others are wrong, 2) they are all wrong. In either case the average of all the results is useless. There may be a slight chance that it’s right by sheer coincidence, but there’s no way to know 8f this is the case.
The claim of a “more consensual picture” is climate science claptrap.
I would suggest that the probability of the average being correct is no greater than that of any member of the ‘ensemble’. That also holds for the GCMs as well
Isn’t that exactly climate seance works?
Didn’t Gavin admit that averaging the average run of all climate seance models gives the “right” result?
thats like mixing vanilla with dog poop … you still end up with useless ice cream …
Yes but if you increasingly mix solar wind and hydro with coal gas and nuclear generated power then what do you get? You won’t be able to see the dog poop at night and they’ve got you there.
What do you expect? These are the folks who “average” many different runs of many different “Climate Models”, each with a different set of assumptions, and assume that this “average” is something useful.
All models are wrong. But some are useful…
Only if you know precisely where they are likely to be in error. This is my experience from the semiconductor industry, where everything is designed from models. Models only work after being tweaked constantly after real world tests to identify the “whoops, shit” problems. Trouble with climate models is it takes 100’s of years to get a realty check, if ever.
It means scientific facts are established by popular vote.
Three observations concerning such an obvious result:
Some are and some aren’t, that’s the trick😉:
“multiproxy temperature reconstructions from tree rings in Mann style suffer from a form of survivorship bias. In brief: from population of tree ring width time series, they screen out series that go down (ex post), then average remainder, which miraculously also goes up” (Stephen McIntyre).
Rud, instead of saying “wow, a 1 C spread in the modern warming period means none of the approaches are accurate” they say “lets average all the incorrect approaches to ensure the gravy train continues,” the same as they do for the UN IPCC CliSciFi climate models. Tree rings have been known for some time not to be a reliable proxy for temperature but they keep bringing in the grant money. The divergence problem alone should have buried tree rings long ago.
They only have to look at any plantation, not all trees grow at the same rate. Everything in nature varies in one aspect or another, nothing is a clone.
It amazes me that “climate scientists” would agree to participate in this study.
It was a double blind study, so nobody agreed to anything.
“It should not have taken until now to run this embarrassing experiment.”
Isn’t that the truth!
The last paragraph is priceless. As with the CMIP process, it seems that the fact that all the models produce different results but, at best, only one can be correct, doesn’t bother them. Oh no, rather than striving to find out which is the closest to reality, let’s just average the models in the knowledge that substantially all results must be wrong. Then we get an overall answer that must also be wrong. True genius!
Choices on how to crunch the data seem to be considered random errors.
I’m off to go for a little cry.
The problem exists between the chair and the computer.
GIGO averaged
…useful in gardening.
“GIGO averaged”
Perfect description! 🙂
This is what alarmist climate science is based on.
“15 different groups that yielded 15 different Northern Hemisphere summer temperature reconstructions”
Of course they did. How many would you expect? The results are subject to uncertainty. Quantified uncertainty means basically the range of results that different people might get after making different but reasonable decisions. So instrumental uncertainty means the range of results you might get using different instruments (and maybe observers). Sampling uncertainty means the range you might get taking different samples. Etc.
The uselessness of this article is that it gives almost no information on how different they were.
Just follow the link given in the article – the writer doesn’t need to provide proof if the paper’s result actually admits the results are widely varying, he’s just repeating the results.
“he’s just repeating the results”
He isn’t. What were those results? Anyone know?
The key thing would be how the spread of results related to the acknowledged uncertainty. Because uncertainty means you expect a spread.
Nick, Stop It!
Follow the link to the paper.
Lets see: 1 C is about the difference between the temperatures at the end of the Little Ice Age and today. This method assures us we couldn’t tell with any certainty the difference between the Medieval Warm Period and Little Ice Age. Shades of the Hockey Team!
50 Shades of the Hockey Team, a veritable spectrum, where predictive power diverges from observation in time, space, systems, and processes, while entertaining diverse skill sets (e.g. models) through consensus.
“This method assures us we couldn’t tell with any certainty the difference between the Medieval Warm Period and Little Ice Age.”
No, it doesn’t.
Nick, I won’t play word games with you. You know that this bogus “study” reflects 15 hocky stick reconstructions, all made up by the use of numerous discredited proxy series, including at least one Bristlecone (stripbark) Pine series from the White Mountains in the Great Basin of the SW U.S., the same series used by the fraud Michael E. Mann. If anybody wants to read about the frauds perpetrated on unsuspecting taxpayers read:
The Hockey Stick Illusion by Andrew Montfort
Blowing Smoke by Rud Istvan
A Disgrace to the Profession by Mark Stein
And one should also read these books listed below and you will be up to speed on the Hockey Stick fraud, the IPCC fraud, and all the rest of the fraud that makes up modern-day alarmist climate science.
Climategate by Brian Susskin
Climategate: The CRUTape Letters by Steven Mosher and Thomas W. Fuller
The Delinquent Teenager by Donna Laframboise
Thanks, Tom.
Yes, it does mean that we can’t tell any difference between warm and cold periods. It is like these trees had almost constant growth until 1850 and then experienced a growth spurt only because of warmer temperatures.
It is highly unlikely that only warmer temperatures spurred exponential growth without other contributing factors such as increasing nutrients like CO2 and water. This then makes temperature unrecognizable from the other contributors so temperature anomalies are biased guesses at best.
Even if the spread is very narrow, it says nothing about whether the calculated number corresponds with the actual number.
All it would take for that to happen is a systematic bias.
Any one factor not accounted for, or accounted for improperly.
What are the odds that all of the possible variables have been identified and accounted for exactly correctly?
I don’t see any Roman Warm or Medieval Warm Period in those results. Nor a Little Ice Age. I’d say all 15 groups are biased and they are all wrong.
Well maybe there wasn’t a Roman warm period, and those Roman legions didn’t conquer northern Europe wearing skirts and sandals. Maybe Charles Dickens was in on the
conspiracyconsensus andliedexaggeratedembellished about the chilly temps in London just to make Tiny Tim’s misery more compelling. And those guys shoving icebergs out of the way so George Washington could cross the Delaware River? Artistic license, surely.The invalid 15 proxy tree ring series they all used were cherrypicked from a group of proxies that were shown years ago to produce hockey sticks on purpose. This “study” is another example of taxpayer dollars going to create propaganda and to perpetuate an ongoing fraud to dupe unsuspecting citizens. It began with Michael E. Mann’s original MBH98 hockey stick in the UN IPCC CliSciFi Third Assessment Report and has continued ever since despite numerous studies exposing the paleo climatological “Hockey Team” knowingly using fraudulent data and methods, especially studies and papers by Steve McIntyre and Ross McKittrick at the Climate Audit blog.
In 2006 the National Academy of Sciences publicly told all of the paleo climatological practitioners to: 1) Quit using stripbark-type trees; 2) be very careful when using trees at all; 3) completely reveal all data and methods; 4) only use statistical methods vetted by professional statisticians; and 5) use multiple statistical verification tools to validate the significance of their study results. The politicized field, naturally, continues to ignore those firm guidelines.
If 15 groups were given a set of initial and boundary conditions and asked to solve a differential equation, would you expect 15 different results? Hmmm, I didn’t think so. What this reveals is that there is no good procedure for generating temperature reconstructions from tree rings, and we ought to be suspicious of those who claim they can but don’t clearly reveal the limitations of their methods. Worse still are those who make such reconstructions without regard to proxy resolution and then tack on the instrumental record, but surely no researcher would be so dishonest… 😉
“asked to solve a differential equation, would you expect 15 different results?”
Yes, if it is a numerical solution. The range should be small, but there is some. Even rounding errors.
1°C is not rounding error. That is the baby and the bathwater.
The baby, the bathwater, and, barring natural and anthropogenic selection, the evolution of a viable life unto herself. Thus the science detailing the propagation of error in an open (or unwieldy) environment.
“1°C is not rounding error.”
But what is “1°C”. There is no serious quantification in this article. There are 15 recons over 2000 years. Is it the max difference between any pair for any year? If so, it is not surprising.
Who gives a shit, Nick? All of the 15 use the same discredited proxy series to get their individual hockey sticks. Just the bristlecone stripbark pines alone will give you a hockey stick, much less the other crap series still being used by the CliSciFi paleo climatological frauds.
Climate Audit’s Steve McIntyre comments that PAGES2k has degenerated into industrial ex post screening. Referring to the paleo climatological practitioners he says: “Rather than progressing, the field has degenerated in the past 10 years.” The crap put out in this “study” is a prime example of that degeneration.
An anomaly of 0.2 ± 1 is not a very good number. Technically it means one can not know whether 0.2 is a proper measurement. It could be value between 1.2 and -0.8. That is what error bars are designed to indicate. It also tells you that the mean of the ensembles has a very large range.
I could find no discussion of systematic or random error being discussed as it pertains to the data points. The authors just assume that the output of the “models” used to predict anomalies are accurate to the nth degree.
It simply boggles the mind to think that these climate scientists believe that their estimates of temperature differences from tree rings lack any uncertainty at all. The paper indicates NO uncertainty associated with the anomaly estimates nor how these propagate into the final values. Amazing, just SFA (simply ______ amazing).
“Worse still are those who make such reconstructions without regard to proxy resolution and then tack on the instrumental record”
And the “instrument record” they tack on is just as dishonest as the tree ring reconstructions.
The unmodified written temperature records don’t show a Hockey Stick “hotter and hotter” temperature profile, instead they show it was just as warm in the Early Twentieth Century as it is today, which means CO2 is a minor player in the Earth’s temperatures.
The “instrument record” referred to here is what results after the Dishonest Data Mannipulators put the written temperature records through their computers and out pops a “hotter and hotter” Hockey Stick profile. It’s a Big Lie. It’s THE Big Lie. This Big Lie has caused a certain segment of society to go insane, and do insane things like building windmills and wasting $Trillions of dollars trying to regulate CO2.
The two charts above show the true picture. The chart on the left is the written, U.S. regional surface temperature chart, and the chart on the right is the “hotter and hotter” bogus, dishonest Hockey Stick chart.
The written temperature record shows it was just as warm in the Early Twentieth Century as it is today. All other unmodified regional charts from around the world show this same general temperature profile as the U.S. chart. That means we don’t have to worry about CO2.
The bogus, dishonest Hockey Stick chart eliminates the warmth of the Early Twentieth Century with their computers to create the false reality that temperatures are getting hotter and hotter and hotter and we are now living in hottest times in the last 1,000 years. It’s all a Big Lie spawned by dishonest data mannipulators and their computers.
Our leaders are bankrupting our societies over this Big Lie.
Yup!
And this next one reveals why they did the above adjustments in the amounts shown: They adjusted the measured values proportionately to how much CO2 was in the air at the time.
Which is exactly what one might do if the purpose was to make it appear that temperature was CO2 dependent.
Those two graphs tell the entire story of the global warming doomsday lie, and the blatant and deliberate fraud that is ongoing in order to perpetuate the entire scheme.
No one interested in the actual truth, or interested in doing actual science, would ever do this, and no honest effort to make corrections to past measured data could accidently follow such a pattern.
This is the literal smoking gun of fraud, committed by the entire “climate science” community.
15 students are given a homework assignment by a professor.
They all come back with different answers.
Who was right ?
Would it be right for the professor simply take all 15 answers, averages them and call it the corect answer, regardless of whether it really is ??
Nick’s just being Nick.
A true defender of the faith.
It’s just as well for him that he chose to follow Mike Mann not Jim Jones.
And failing miserably… as usual.
Of course what you describe is perfectly acceptable…That is in fact how most grades are assigned in America’s esteemed universities
If you have 1 math problem and 15 students with 15 separately unique and different answers, most likely you have 15 wrong answers and 1 bad math teacher. If you’re lucky 1 out f 15 managed to stumble on the RIGHT answer and the other 97% have the LEFT answer.
“In summary, the results ranged by as much as 1°C.” I wouldn’t call that “widely varying” for a reconstruction.
They used exactly the same dataset – all groups started from exactly the same point. If this had been 15 groups following a set methodology then they all should have arrived at the same point with virtually no difference between them. The fact that they varied by up to 1′ indicates that there is no set methodology to guide them, it appears to be guesswork within broad parameters. Not science.
There is currently no set methodology. People do what seems best for their circumstances, as usual in scientific research. They figure it out, and that is how progress is made. There is a component of uncertainty due to methodology. Again, differing reasonable decisions can be made.
Yes, all computer games are often constructed differently.
Mario Bros is different from Tetris, is different from PacMan. !
But they are still just games.
<sarc>
Well, thank goodness this form of scientific research isn’t guiding the spending of billions of dollars of taxpayer money, eh?
</sarc>
You are right, in an area where scientists are still trying to get a grip on the subject you will indeed find many different estimates and results. Estimates of inferred values and, importantly, forecasts may vary substantially.
Notable examples were in medicine in the 19c. We had the miasma theory of the cause of malaria, cholera and typhoid, and while it was being refuted and replaced by the correct accounts there were widely differing views on causes and on what policies would reduce incidence, and why.
However the reason for doing the present kind of study is to guide policy. Its proposed, on the basis of series of temperature reconstructions such as those done in the piece, to make huge changes in the way we live and work.
The argument is that the reconstructions show that current warming is exceptional and unprecedented and disastrous if it continues. The argument is then that the cause of it is CO2 emissions. The policy conclusion is that these must be stopped.
Take away the first premise and the argument falls apart. If there is no proven unprecedented rise in temperature then there is nothing to explain and no need for any new policy. So its quite critical that the evidence for the rise be absolutely cast iron, given the scale of the policy recommendations that depend on it.
The present study appears to show that tree ring proxies are not fit for the purpose of guiding policy in the necessary way. Qualified practitioners, confronted with the same data, differ widely on what the correct temperature series is.
The question I would raise about the study is whether it was thorough enough. Its not clear it controlled for expectation bias. It should have included some series which were not real historical tree samples. Perhaps the historical series but with the results randomized. The interesting question would be whether the experts would have seen rising temperatures in series which we know they could not show. Or you could try if the experts could differentiate random data from real historical data.
The null hypothesis on tree rings ought to be that given any series purporting to be tree ring samples covering the period from 1800 to present, a group of experts will produce hockey stick reconstructions regardless of the nature of the supposed data. Including if it is randomly generated data.
What the experts are doing is a bit like diagnosing a medical condition – eg staging a prostate biopsy. The way you develop that skill is by training against known samples with a known diagnosis. That is also the way you test for skill on the part of the trainee. Need to do something similar with tree rings.
“However the reason for doing the present kind of study is to guide policy.”
It isn’t; the reason is curiosity about the past. Policy is determined by what may happen in the future. Whether it was warm in Roman times is of historic interest. The proposition guiding policy is that burning C will warm the climate in coming decades, to a possibly damaging extent. That is something that hasn’t happened before.
But, Nick, you have not answered the fundamental point.
You are correct that the proposition guiding policy is that there will be damaging CO2 driven warming.
But that proposition does require the present warming to be unusual in the historical record. Otherwise one could and would argue in reverse – the climate is not doing anything different from what it has done before, so it seems that, by whatever mechanism, the forcing effect of the CO2 we are emitting must be compensated for. Negative feedback, maybe.
Its a real problem in the logic of the case if we are just looking at a series of temperature fluctuations, none of which are unusual in speed or amount, and then we take just one of them and ascribe a unique cause to it.
From this point of view the rise in the early 20C is particularly problematic. It looks just like the rise in the last part of 20C and turn of the 21st century.
You would be left with the only real argument open to Arrhenius: this forcing effect will produce damaging warming. But with no evidence that any unusual warming is happening despite 70 or so years of the forcing effect.
There was a reason why the Hockey Stick was so striking and was so vigorously taken up and used. It seemed to show that something new and different was going on.
The study seems to be suggesting that different experts confronted with the same evidence arrive at quite different diagnoses of how much recent warming there has been, and how unusual it is. This, if true, knocks out a key piece of evidence for the policy prescriptions. They only make sense if today’s warming is unusual enough to be attributable to a different cause than what caused the random fluctuations of the previous warmings and coolings.
Surely this is why the debunkings of the Hockey Stick incur such furious reactions? How one looks at the record has a great influence on how secure one feels in making drastic policy recommendations.
Over the years I have been following this debate I’ve come to the conclusion, starting out from a position of acceptance of the CAGW theory, that there is nothing unusual about recent warming, that CO2 emissions have a forcing effect but that their impact on global temperatures is minor, because feedbacks in the conventional theory have been way over estimated. That recent warming is probably wholly or largely natural in origin. And that the various proposals to lower emissions, wind, solar etc are futile. They will neither lower emissions nor if they did make any significant difference to temperatures.
Nor for that matter will they be implemented on a global scale sufficient to have any material effects on global emissions.
Nor is a degree or even several degrees of warming in any way harmful to life on a planet in the midst of an ongoing ice age.
Nor is CO2 in any other way harmful to life on Earth. It is in fact the basic building block of every molecule of every living thing on our entire planet, past, present, and future.
Nor is the amount in the air right now excessive, in fact it is still far too low for the biosphere to be robust.
Michel,
“But that proposition does require the present warming to be unusual in the historical record. Otherwise one could and would argue in reverse – the climate is not doing anything different from what it has done before, so it seems that, by whatever mechanism, the forcing effect of the CO2 we are emitting must be compensated for. Negative feedback, maybe.”
No, that’s where it goes wrong. You can’t argue in reverse. Policy is determined by what is expected if we continue to dig up and burn carbon. That activity is truly unprecedented, and we can’t learn about its effects from history. There was then no “forcing effect of the CO2” to be compensated.
All the paleo studies suggest that past variation was small, and this study does nothing to upset that. The 15 results were not identical, but they agreed that nothing much happened. The complaint here is that variability between studies suggests that we do not have proof beyond reasonable doubt that nothing happened. I think we pretty much do, but even if it turned out that there was more variability in the past, that doesn’t disturb the basic proposition that burning C will make it warmer. Even if there is a possibility of a naturally caused climate problem in the future, that doesn’t excuse creating a manmade one that we could avoid.
You are making assertions with no data to support them. The time frame of many paleo studies have resolutions of 100, 1000, 10,000 years or even more. You simply can’t assert that CO2 has increased in the last 70 years beyond any other time in the past.
Even with newer ice cores, the resolution simply doesn’t support this kind of assertion. An ice core with 100 year resolution means the last 100 years would give you ONE measly data point on the graph.
Fundamentally, you are still talking about correlation and not causation. You need to spend your time trying to find out a mathematical function that directly relates temperature to CO2. Until that is done every cooling or pause is a nail in the demise of CO2 being a control knob.
The question is, what is the evidence that CO2 is going to produce the claimed amount of warming?
We can look at current warming, which is happening in an admittedly unique environment of human CO2 emissions. If this warming is different from any other, it would be reasonable to start looking for different causes.
But it isn’t. It is very similar to many other historical episodes of warming. So there is no a priori reason to think it has been caused by any new cause.
In medical terms, this would be like being confronted with periodic outbreaks of the plague, cholera, typhus etc, none of which were materially different in scale, location, severity from the others. But, the analogy would be, you look at some other phenomenon, for instance the rise of factories, and attribute the latest episode to that.
The correct scientific way to proceed is identify the underlying cause of all the episodes, then show that it does not operate on the latest one, and then you have something in need of explanation.
I think the argument in reverse is certainly valid. We have a modern warming which is no different from previous warmings. But if the theory is correct, it should be very different. Enough CO2 has been released to make its effect obvious by now. But they are not happening.
As to the predictions, the evidence that nothing much is going on, and its not going on when according to the theory it should be, suggests that its not ‘just physics’.
It is certainly true that added CO2 has a forcing effect. But that is not the issue. The issue is how the climate reacts to it. The conventional theory is that the CO2 rise produces warming, which in turn raises water vapor, which then produces more warming.
If this were correct, it predicts either a faster or higher warming than previously in the historical record. But we don’t see that. Therefore its reasonable to enquire whether there are negative feedback mechanisms to the forcing from CO2, which prevent it having the predicted effects.
To me, all the evidence suggests that we don’t understand properly how a forcing effect from any source interacts with the climate. Its more stable recently than the conventional theory predicts it will be. And its also more variable historically than the theory predicts.
If the theory is correct, there should be a long stable period with no fluctuations of temperature, followed by a sharp rise when CO2 ppm is raised. The assertion of this in the Hockey Stick theory appeared to support this. But that was discredited, and with it the argument that there is something unique about modern times to be explained by some new and different cause. There is neither a long stable period, nor a unique sudden modern rise.
The most plausible forecast therefore is at most a 1C warming per doubling, and nothing to get worried about.
“ The proposition guiding policy is that burning C will warm the climate in coming decades, to a possibly damaging extent.”
So, the logical thing to do, in order to avoid making policy based on an incorrect supposition, is to examine very closely the known relationship between CO2 and temperature, and do so at many time scales.
(We have places with trees that have rings that are also places with carefully kept records of the temperature, over more than a hundred years of time, BTW)
The thing is, none of the reconstructions of past CO2 and past temperature shows anything like an effect described by the supposition in question.
And worse still, none of the policies guided by the supposition, which are now being put into place, will have any significant effect at controlling CO2.
There are some ways to make the power we need that would curb CO2 emissions, and these are being stridently opposed by the same people calling for these policies in the first place!
Geology is one of the oldest and most mature sciences that we have.
Nothing from the geological study of Earth history backs up any of the notions put forth by the climate doomsayers, whatsoever!
Not.
One.
Thing.
Wow. Nick just admitted that global UN policy and international treaty agreements regarding global warming are based on no set measurement methodology, since it was the tree ring data that started the whole charade.
It is where the hockey stick arose after all.
Since there are none, any claim of resulting emergency is bogus as well.
” it was the tree ring data that started the whole charade”
Certainly not. Concern about warming started with Arrhenius in 1896, and his scientific analysis showing that adding CO2 to the air would cause warming. That is still the basis for policy. We’ve done it, and it has been warming. And will warm a lot more.
But even more recently, the establishment of the IPCC (1988), the UNFCCC (1992), and the Kyoto Protocol (1997) preceded the tree-ring based millennial constructions, which tell us nothjng about future warming.
“Arrhenius in 1896, and his scientific analysis showing that adding CO2 to the air would cause warming. That is still the basis for policy. We’ve done it, and it has been warming. And will warm a lot more.”
Warm a lot more, huh? Kind of sticking your neck out there, aren’t you, Nick?
Currently, CO2 is increasing, yet global temperatures are cooling.
The UHA graph is missing context.
It must be viewed in relation to a longer data set, being as how it begins at the coldest point of a multidecadal global cooling trend.
It starts, in fact, at what was likely the coldest few years in the last 100+ years.
The charade Nick, the charade. Its all about disastrous hockey sticks and tax money, Arrhenius had nothing to do with any of that.
Exactly my point Nick, although a different conclusion. There is no methodology to this, no procedure to follow and no structure to this at all – therefore there is no answer worth a damn. We’ve been using dendrochronology for over 120 years and dendroclimatology for over 50 years and you are telling me that we are no closer to a set methodology now than when we started? This is not science, this is guesswork and ideology for money.
“We’ve been using dendrochronology for over 120 years and dendroclimatology for over 50 years and you are telling me that we are no closer to a set methodology now than when we started?”
We have been performing numerical integration since Newton; that is about 350 years. But there is no set methodology. There are different methods with different merits. Yet we use numerical integration to design bridges, airplanes, just about any mainstream engineering activity. It works without a set methodology.
Don’t know when you last engineered a bridge, but I’ll bet never. When I took my civil engineering classes the only question was the span and weight bearing need. From there, strength of materials and fasteners were designed to support what was needed.
I’ll guarantee that even today, different numbers from different teams are NOT AVERAGED to find the final design.
I would much rather drive over your bridge, Jim, than Nick’s 🙂
Hi Nick
I contend that you can win money at roulette by varying your bet size.
To prove this to you, send me a one thousand sample of roulette spins and I will return you a model showing you how to win. Indeed send me a hundred such samples and I will give you a model showing you how to win. Some of the models might have slight variation in bet sizing and period but they will all be based on the same premise of bet variation can win money at roulette. I can do this every time without fail.
So are you convinced by the contention?
Surely you must be, I mean just like the computer models based on past data but dozens of them all showing the same basic result with minor variations.
There can be no other explanation, other than a truthful contention can there Nick?
Or do you think there just might be!
Nick, they DON’T figure it out. That implies that some mathematical rigor is applied to determine a calculated result. I suspect it is more a “guess” based on previous reconstructions who probably did the same thing.
Anyone who grew up on a farm or near nature understands that some things grow big and some grow small with no difference in environment. You can’t go back 100’s of years and determine with any accuracy at all what occurred from year to year.
Whether you believe the Little Ice Age was regional or global, trees from that region should show a several hundred year restriction in growth if temperature is a factor. These simply don’t show that. Similarly, the Medieval Warm Period should have some regional impact if nothing else. Do we see that? I sure don’t.
“There is currently no set methodology. People do what seems best for their circumstances, as usual in scientific research.”
Ok, so how do we validate which, if any, of these reconstructions is correct?
Nick Stokes,
if this comment reflects your true understanding of what exactly constitutes scientific research, you have outed yourself far more effectively than any of your critics could have done.
Using a data set as a proxy for something that the data has no correlation to, is how tea leaf reading works.
Any result can be superimposed on the data, because it has no actual relationship with the parameter being evaluated.
Funny how these “scientists” have lost their enthusiasm for ice cores, benthic foraminifera, archeology, recorded history and such, eh?
Because those methods contain data that actually correlates with past temperatures.
Again, 1 C is the difference between the Little Ice Age and today. Hell of a miss, wouldn’t you say?
But again, what exactly differed by 1°C? No-one seems to know or care.
Nick, I didn’t give a shit once I found out the “study” was just a mendacious PR stunt on the part of the CliSciFi paleo climatological frauds. You know damned well that the Hockey Team cherry picked all the existing paleo tree ring series that result in bogus hockey stick reconstructions for this “study.” You also know that there are numerous sources that debunked the fraudulent hockey sticks, such as:
The Hockey Stick Illusion by Andrew Montfort
Blowing Smoke by Rud Istvan
A Disgrace to the Profession by Mark Stein
“ the “study” was just a mendacious PR stunt”
So what is the point of this WUWT article?
How would I know, Nick? Maybe an editor didn’t dig into it deep enough?
Add Steve McIntyre’s debunking of the hockey stick and team.
Yep, Gerald. People should go to Steve’s Climate Audit Site and also read:
The Hockey Stick Illusion by Andrew Montfort
Blowing Smoke by Rud Istvan
A Disgrace to the Profession by Mark Stein
Unfortunately there are so many broken links at CA that in-depth study is often impossible.
Its a pity that the individual scientists and mathematicians trying to perform real peer review operate on shoestring budgets. With all the billions of dollars poured down the CliSciFi rathole you’d think they could siphon of a little to at least straighten out the paleo climatology political corruption. On second thought, its the politicians and politicized Deep State that fund the politically-corrupted “science.”
I have to agree with Nick the article is lacking detail of how variable.
Clearly its a bit of a problem if the variance is greater than the difference between the LIA and the present, but how did the distribution of results look.
Maybe an Olympic’s diving system should be employed in climate science where the high and low go unpaid or even better have to pay the others etc.
It would focus the thinking.
Not exactly science though.
The purpose of the “study” was to use corrupted tree ring proxy datasets to normalize the practice of mashing together bogus hockey stick “reconstructions.” Steve McIntyre at his Climate Audit blog reveals the complete and irreparable political corruption of the paleo climatology field. Also read:
The Hockey Stick Illusion by Andrew Montfort
Blowing Smoke by Rud Istvan
A Disgrace to the Profession by Mark Stein
The irony here is that Nick’s pointing out the inevitable errors involved in such reconstructions, which is actually a fair and reasonable point. The problem is that when it suits them to ignore errors, climate scientists do just that.
For instance, none of this would matter IF — and it’s a huge IF — climate scientists provided confidence intervals for the predictions made by their models looking into the future. Yet they never do. Why? Because the confidence intervals would inherently be close to zero. In other words you might as well make predictions for climate change using a couple of dice.
This is the greatest flaw in climate science. Conclusions are drawn on the flimsiest of hard evidence with the results quoted as gospel when they’re anything but.
Nick maybe “pointed out the inevitable errors” in the data collection, but he is implying the different results of the reconstructions are because ” instrumental uncertainty means the range of results you might get using different instruments (and maybe observers). Sampling uncertainty means the range you might get taking different samples. Etc”.
But , that is irrelevant. “Each group used the same network of regional tree-ring width datasets.”, not different readings/observers/samples
If they are all working with the same initial data, then the only errors are in their varying interpretations of that data.
But what uncertainties are associated with each data point? That is the real question.
Exactly.
The most honest findings the climate “scientists” should be providing to IPCC Summary For Policy Makers are –
“we just don’t know”
” IF — and it’s a huge IF — climate scientists provided confidence intervals for the predictions made by their models looking into the future. Yet they never do.”
Just not true. They always do. Here is the main table from the SPM of the AR6. Every single number has a confidence interval. The graphs show that also.
Phantasy numbers spat out by unverified UN IPCC CliSciFi models based on speculative numbers: Not even GIGO. They can’t even get the present temperatures correctly.
Their conclusions are based on Arrhenius hypothesising in1896 that adding CO2 to air would cause warming.
He also said we should add more CO2 on purpose because warming is good.
“So instrumental uncertainty means the range of results you might get using different instruments”
“Each group used the same network of regional tree-ring width datasets.”
Standard Nick lack of basic comprehension. !
leading to a total strawman non-argument.
Does this actually apply to calculation error? It’s the same dataset. The variation comes from how the data is handled.
What this study shows is that the lack of a justified method for using a proxy (trees) means that the calculations vary by as much warming as we’ve had in a hundred years. So do they seek to find a justified method?
No.
They take all the methods and hope that they are incorrect randomly – equally biased warm to cool.
But all the methods were made by people who have decided to devote their careers to studying climate science. They have been pre-selected to think that climate science is important. The bias will not be randomly distributed.
It’s like determining the existence of God by going to a Catholic Seminary and asking the experts who study Him. You will get an answer. But it won’t persuade those who don’t already share the faith.
“means that the calculations vary by as much warming as we’ve had in a hundred years.”
Again, there are no facts here on which that is based. It isn’t said in the paper. Someone has looked at the paper and said “Hey, something is different by 1°C”. But no-one seems to know what it is.
“The variation comes from how the data is handled.”
Well, of course. But it isn’t “calculation error”; it is how you infer globally from a series of point samples. That necessarily involves reasoning about what happens at points not sampled (in time also, since the information is seasonal). This is a pretty universal issue in science. Most results are deductions from sample observations.
The odds that one is right is a little more than 6%. But that’s not the issue The fact that two or more did not agree is asymptotic to method and shows that no skill exists regarding temperature reconstruction from identical tree ring input data.
Even in horse racing more than one horse is usually in the finish line picture.
You didn’t read the paper did you?
From the paper.
The paper declares that these are “a reasonably robust predictive skill for different frequency domains from interannual to centennial.“
I certainly don’t see these as approaching a robust prediction of observed values.
It is unusual to see a time series analysis done. Yet this kind of analysis shows very low statistical values of the coefficients which makes one believe that they are far from being a good representation.
All of the people arguing about statistics are falling into Nick Stokes’ trap of assuming the study was set up to find a valid scientific result. It was set up to use invalid or otherwise corrupted tree ring proxy series (including temperature-nonresponding stripbark pines) to normalize the practice of mashing together invalid hockey stick graphs produced by the politically corrupted paleo climatology community to, in part, support the bogus UN IPCC CliSciFi hockey stick graph placed in their AR6 summary. [Sorry, I’m out of breath just typing that sentence.]
I know its repetitious, but visit Steve McIntyre’s Climate Audit blog and read:
The Hockey Stick Illusion by Andrew Montfort
Blowing Smoke by Rud Istvan
A Disgrace to the Profession by Mark Stein
The rule on gardening or growing plants generally is that growth is affected by what is limited. It could be water, sunlight, major nutrients in the soil, trace nutrients, insect or disease challenges, or temperature. If and only if temperature was always the limiting factor would tree rings indicate temperature only.
Treemometers are a silly idea.
For farm crops, good growth is generally more dependent on rainfall and when it occurs than on average temperature. I don’t see why trees wouldn’t show the same effect. But the experts wanted a proxy for temperature so we get a rainfall proxy with a y-axis calibrated in temperature….sort of like a car speedometer calibrated in miles per gallon instead of miles per hour.
That is why the 2006 National Academy of Sciences report, among many other studies, indicates that tree ring proxies are not good for determining temperatures. All studies show that stripbark trees such as the bristlecone and foxtail pines, especially, are not responding to temperatures. It is a fact that, despite rising 20th Century temperatures, tree ring proxy series in general show a decline in temperatures during that period (the divergence problem).
Additionally, because of their temporal frequency problems tree ring proxy series all produce hockey stick handles. Experts recommend using the many other available proxy types such as d18O to reconstruct temperatures extending back beyond a few hundred years.
The politically corrupted paleo climatological community continues to use stripbark trees in their reconstructions, as reflected in the 15 tree ring proxy series used for this “study.” People fall into Nick Stokes’ trap of arguing the statistical validity of an unscientific study.
Trees are most in need of increased atmospheric CO2.
That is what “hockey stick” graphs tell us.
They show the highly beneficial impact of increasing atmospheric CO2 from a bare subsistence level (hence flat graph) to a period where CO2 becomes more available to plant life.
As proven by NASA’s pictures from space showing the world has greener a massive and obvious 20% over the last half century. Much better climate indicator than a measly 1.2°C over a century and half – and that was only by starting from quasi-ice age conditions.
And yes I know I’m preaching to the choir, but I don’t say anything then the very carbon atoms themselves will yell out.
But human emissions are only about 5% of the carbon cycle….so 16% greening should result in nature using up more than we emit….no?…asking for a friend…
These studies are not the sort of nonsense that we should be wasting trillions $ on until 2050 or until 2100.
Never forget that their claim that Humans are facing an EXISTENTIAL THREAT if we don’t lower co2 emissions is a complete LIE and FRA-DULENT nonsense.
Here’s the Human data since the start of the IND REV until today.
In 1800 the average Human life exp was under 40 and had been for the previous 200,000 years.
Here’s what happened in just 222 years.
So 200 K to reach 1 billion by 1800. Then just 127 years ( 1927) to reach 2 billion. Life exp under 45.
Then just 33 years ( 1960) to reach 3 billion. Life exp 50 years
Then just 14 years ( 1974) to reach 4 billion. Life exp 58.5 yrs
Then just 13 years ( 1987) to reach 5 billion. Life exp 63.4 yrs.
Then just 12 years ( 1999) to reach 6 billion. Life exp 66 yrs.
Then just 12 years (2011) to reach 7 billion people. Life exp 70 yrs.
Then just 12 years ( 2023) to reach 8 billion people. Life exp 73 + yrs. See link Macro-trends. As at 2022 life exp is 73 and population is over 7.9 billion people. THINK ABOUT THESE NUMBERS and the 7.9 bn Humans are OBVIOUSLY healthier today and wealthier today.
But the rate of increase in population has declined since the 1960s, except Africa. Hooray for FOSSIL FUELS and of course they GENERATE over 80% of the World’s TOTAL energy today.
https://www.macrotrends.net/countries/WLD/world/life-expectancy
No data given at all in this post. Somewhat disappointing, but par for the course.
Helpfully there is a link to the paper in question, so I surfed over to take a look.
There are some composite graphs, showing what seems to be all the reconstructions. Just what I was looking for.
Granted I only skimmed the paper, I just wanted to see the plotted results. You should check if you have a question.
SURPRISE!!!
They are *all* hockey sticks.
No Medieval Warm Period, no Little Ice Age. Just flat for 2,000 years, then shooting up sky high in the modern era. One name that popped up repeatedly was PAGES, as in the notorious PAGES2K paper. This time as PAGES19. Make of that what you will.
What’s the point of doing treemometer reconstructions if you don’t end up with a hockey stick. Mann taught the next generation what to do for fame and fortune.
Note the two locations in the Western U.S. on the above map. We could ask Steve McIntyre (Climate Audit blog) where “SCO” is located but for damned sure “GTB” is in the Great Basin where all the stripbark pine samples were taken. The National Academy of Sciences (2006), in response to a high-level scientific review of Michael Mann’s hocky stick, in no uncertain terms told the entire paleo reconstruction field not to use stripbark pine trees. They also cautioned against the indiscriminate use of tree ring width proxies in paleo reconstructions.
Naturally, all of the paleo teams continue to use stripbark pines up to today as shown in the above map in order to get hockey sticks and continued Deep State funding. Additionally, they continue to use manifestly unfit proxy series such as those from the Yamal Peninsula “YML” and others, above. It is entirely possible that “QUL,” above, is from the totally discredited and improperly filled-in series from the Gaspe Peninsula in Quebec. PAGES2k, with over 70 people involved, is particularly nasty in the use of bad proxy series (stripbark pines, etc.) and by using a proxy series upside down in its reconstructions.
This “study” is a clear attempt to add justifications for the UN IPCC AR6 displaying a hockey stick graph in its summary (its not identified in the body of the report). It is a poorly disguised attempt to justify the corrupt paleo climatology community’s malfeasance in continuing to produce hockey sticks to feed to their political masters’ CliSciFi frauds and fearmongering. Please go to Steve McIntyre’s Climate Audit to get a full analysis of all the hockey sticks.
I expect to see more of the alarming hockey sticks pumped into the complicit media. There is a full court press going on by the politicians, Deep State, CliSciFi, NGOs and media because their narrative is falling apart: Temperatures are not rising as projected, extreme weather is not becoming more frequent or severe, CliSciFi climate models are being shown for the junk they are and people’s power bills, taxes and reduced spending power (runaway inflation) is becoming more apparent. Hang on to your hats.
I found it.
SCO = Southern Colorado Plateau
Stripbark pines, Tony?
Remember Keith Briffa was the tree ring go to guy at CRU and he said in one of the emails
“I believe that the recent warmth was probably matched about 1000 years ago”
Keith Briffa also produced at least one study showing that tree ring proxy series did not reflect a temperature signal.
Never occurs to treemometer reconstructionists that the tree ring response curve to temperature is likely multi-valued not linear. Which means tree ring can never reconstruct temperatures without an additional control variable. Which they don’t have.
You know, the curve could look like an upside down U shape
I have wondered how you would come up with a calibration certificate for tree rings. I am actually surprised they got only a 1 degree range.
Its in the works. ISO 2023
The “study” was planned out to come up with an unalarming result. It is designed to get people to accept hockey sticks in an ensemble; more teams get to dip their beaks into the Federal dollar ocean.
Two things that should always be required when publishing “science” reports/papers: 1) the raw data, and 2) the methods and processes used to analyze the data.
While my doctorate is in a different field (psychology) I agree there should be better methodological requirements as, unfortunately, the utilization of this hockey stick “science” does have a profound impact on mental health. Also unfortunate is the same loosening of sound scientific methods and honesty in my field, and concomitant exploitation of “data” for the same reasons found in climate studies – power, and control of the masses. Enough of this cult mentality.
The title says it all!
The historic global temperature record prior to the advent of satellite-based measurement in 1979 is not reliable.
Anybody who tells you otherwise is either a fool or a liar.
This chart is not reliable?
Ensemble reconstruction: Where a collection of model results, with one possible best result, is averaged with all the inferior results and declared to be the most probable correct answer.
Why would anyone recommend such a procedure? It would seem that they are trading off accuracy for a function with less apparent variation but much larger real variance than the individual members of the ensemble.
Socialism in action.
Unfair and triggering to not give participation ribbons to all therefor all shall be considered in the final result.
It’s sort of, consensus
Imagine the ruckass and self-cancelling that would be needed if the climate gamers started squabbling with each other.
Far more of a “safe zone” to just average all the computer game result. !
I think you might be able to do better than averaging them _all_ together.
Results that show a cooling trend are obviously wrong, and should be excluded.
/sarc
Yes, only the Goldilocks Optimum should be retained.
The one that makes the biggest hockey stick?
Yes, you can add the means and divide by the number of the means, but the variances add directly with no divisor.
This seems like an attempt to validate temperature reconstructions from tree ring data. It seems like the way to do this would be to compare them with other non-tree ring based temperature reconstructions, Instead, it’s like, well, if we all agree, this must be correct. Sorry, but no.
We know why.
Consider another temperature proxy which could be isolated from the wood. Perhaps isotope ratios, just for example.
What if the second proxy told exactly the opposite story as the tree ring width???
That is why they do not do it. As Rud observes above, tree ring widths gives the correct answer, therefore they do not dare use something else, like wood density or isotopes or anything else.
Actually, without stripbark pines temperature reconstructions would tend to go down in the modern period. The “divergence problem” is the tendency for tree proxies to show cooling in the 20th Century.
“But as the study describes, each group employed a distinct reconstruction approach. ”
The problem here is if a dataset doesn’t show a trend, in climate science a battery of test statistics is done from which is selected one that does have a trend. Michael Mann found a “novel” stat approach that converted any red noise into hockey sticks. We didnt get to check his garbage can for all the failed trials.
Even this was not strong enough for his liking and so he shifted through the Yamal data set from Siberia and chose a single tree that gave him what he wanted! He also used Strip Bark Pine, a tree the dendro folks said is not suitable, but he liked it so much that he weighted the selection10x in his construction. He then cobbled on the Tiljander Lake bottom mud series upside down. Finally, because the high end of dendro sagged down (the so-called divergence problem) which should have been understood made the data unsuitable as a temperature proxy, he cut the sag off and carefully grafted the recent fiddled thermometer temperatures on as the blade.
This was a science free study. Making data do what you want it to do is a glimpse into the creation of the socialist worldview.
If the datasets as they are, do not show a trend to the disinterested observer, they should be rejected out of hand.
Gary, as you know the datasets (tree ring proxies) were pre-selected to give hocky sticks no matter the method used to jam them all together; stripbark dominate and are overweighted compared to the other proxy series. And the Gaspe proxy gets rid of the Medieval Warm Period all by itself!
From the Nature article:
Quote:”Despite some indication of late Roman warming (in the latter half of the 3rd century) and Medieval warmth (roughly between the 10th and 12th century), all reconstructions lack obvious signs of long-term orbital forcing
Wasn’t that a funny thing to happen = The Roman Warm Period coincided with when the empire went earnestly into decline.
iow: A. Warm. Period. did not create The Romans, The Romans created the warm.
And Mankowitch was nowhere in sight
While The Ancestral Puebloans created the 10th thro 12th century warm period.
See where they lived – the brown bits on the attached map.
Isn’t it crazy how The Climate knew exactly where to change and thus take those innocents down.
After they’d burned all the trees and so ‘destroyed the evidence‘
See the problem with these, and all, tree-ring analyses?
The only places where there are any viable trees left to analyse are where humans didn’t cut/burn them all – hence The Climate at those places (seemingly if the tree-rings carry any weight) remained cool.
Has got to be The Most Hideous bit of cherry picking and bias there ever was in this insane charade
“all reconstructions lack obvious signs of long-term orbital forcing” means that none of the reconstructions reflect the known effects of orbital forcings. Since the reconstructions do not reproduce known orbital forcings, they are worthless.
That’s because they didn’t use Mikey’s single magic tree and the magic algorithm that always produces a hockey stick no matter what you pump into it
BTW: What happened to Mann and Steyn?
They are both ten years older.
The original Mann et al ‘hockey stick’ (MBH99) and iterations were superb propaganda tools and much of the subsequent hysteria can be traced back to the prominence given to it in the IPCC third assessment report in 2001.
It was also a masterful piece of illusion using the classic conjuring trick of misdirection, the world was mesmerized by the ‘blade’ while ignoring the ‘handle’ which was merely an approximate average of a lot of disparate proxy samples that indicated a general temperature trend from the MWP to the LIA.
The clue is how the uncertainty shading narrowed over time until it almost disappeared at the start of the instrumental record around 1880.
Why would that be, do trees slowly learn how to simulate temperature as they grow older?
Wisdom with age! 🙂
This is funny, I am rereading Times of Famine Times of Feast and I really don’t see how you can screw up using tree ring data unless you are doing it intentionally. Its not rocket surgery.
Ambiguity is the hallmark of inferential logic.
Unsurprising to see 15 very different groups of clowns emerge from the tiny car at the tree-ring circus.
Interesting, the tree rings which work well for 1880-1960 suggest that the temperature anomaly is around half the current value as measured by thermometers (Figure 3c). I suggest some official adjust those tree rings pronto!
The paleo climatological frauds do that by ex post facto screening of tree ring proxy series to get rid of any that don’t give the right answer. They admitted publicly that “one has to cherry pick if one wants to make cherry pies.” They call it “getting rid of proxy series that don’t show a temperature signal.”
“Interesting, the tree rings which work well for 1880-1960”
Ever hear of the 1940’s “blip”? Phil Jones?
What you have is bogus tree ring data matching bogus temperature data for the period from 1880-1960.
Did anyone payed attention that they are not using “Mike’s Nature’s trick to hide the decline”?
The “supposed” anomalies decline in the most recent decade at least 🙂
Clearly the self claimed “renowned” Mann has to use the “blue pencil” somewhere in this article.
They then “carefully” cut the latest decade in the “reconstruction”. Compare the end of the X scale of Figure 3 with Figure 4. I still have to figure out how these things pass “peer review” (pal review?).
Data scatter.
Put two humans in a room and show them the same quantitative information and it is guaranteed to produce two different opinions on what it means. Use 15 persons and you’ll get 15 different answers, but the answers will likely show a mean value with proportionally less data scatter. Ditto with any larger group. It’s natural, it’s mathematical.
Yes, two people playing the same computer game, will play it differently..
Your point is ??
Would you expect 15 different conclusions if “the science was settled”?
Duane, do you realize how hilarious is your answer!! One of the main pillars of Science is replicability. Using the same data and the same methodology, results have to be replicable for conclusions to be taken. What you say is not Science, it’s statistics of scattered values. Even so, with the same data and using the same sample, the statistical values obtained must be the same. I know that Climate Science, according to some alarmists, can benefit from your view, to be possible to blame any possible conclusion on humans. However that is not Science at all.
I asked the arborist who treats my huge 100’ maples about tree rings and temperature. He just laughed. The width of tree rings are determined by local precipitation, more gives fat rings, less gives thin rings. If the north side of the tree gets more water than the south side, the north side will have fatter rings. Ring width has nothing to do with temperature.
Of course. Anyone working with this kind of data knows that tree rings are hygrometer proxies, not thermometer ones. That’s why I always get suspicious when Mann (auto-proclaimed renowned climate scientist) writes something. He can only be one of two things: dumb or deceiving.
The only reason they got within a degree is because they knew what temperature they were shooting for.
You think they can really tell the difference between Douglas fir tree rings grown in Seattle at near sea level, where the average July high is 73, and Truckee at over 6000 feet where the July average high is 83?
I don’t.
How do these authors know that the temperature histories from these 9 scattered sites were so similar that they could be added with benefits?
From earlier tree ring proxies?
Circular?
Geoff S
“Differing in their mean, variance, amplitude, sensitivity, and persistence, the ensemble members demonstrate the influence of subjectivity in the reconstruction process. We therefore recommend the routine use of ensemble reconstruction approaches to provide a more consensual picture of past climate variability.” Sorry guys science by consensus is not science.
not science but opiance … opinion dressed up as “science” …
Time to throw these logs on the fire.
Nothing more needs to be said.
Tree rings, is it temperature or water?
Just look at time-lapse filming of desert regions.
One month is very hot, no growth
Annual rains come, amazing growth.
Next month still very hot.
What happened? It rained which caused explosive growth.
Tree rings do not show temps.
The conclusion that “Differing in their mean, variance, amplitude, sensitivity, and persistence, the ensemble members demonstrate the influence of subjectivity in the reconstruction process. We therefore recommend the routine use of ensemble reconstruction approaches to provide a more consensual picture of past climate variability.” is just plain wrong.
What they have found is that tree-ring reconstructions only vaguely represent past temperatures — probably just “better growing weather” instead — and cannot reliably tell us anything about temperature itself.
Averaging bad data — unsuitable data — from different groups does not produce good data.
Never did, never will.
(I will try to write a full essay on this as it violates the rules of scientific evidence.)
“We therefore recommend the routine use of ensemble reconstruction approaches”
Doesn’t that essentially amount to “let’s average a bunch of guesses that may or may not be right”?
First:
Tree ring width varies.
Second:
To what degree is it true that these trees add one ring per year? This can be observed. Take a known grove, and cut a couple trees per year, and count their rings.
Third:
For observable time spans, is there a mathematical correlation between ambient temperature and tree ring width? This can be observed. Take a locale with a 60-year temperature record, and correlate that with the tree ring width of a tree known to be 60 years old. Memory, or photos, can verify tree age.
Fourth:
Doesn’t it seem that as a tree grows, its inner rings might get compressed, to some degree? We get better violins with hardwood that has been “aged,” allowed to dry – the moisture in this wood may be left to age from 5 to 20 years, with apparent differences in 5yo wood versus 20yo wood – all things being equal.
This could be measured, empirically. Not exactly sure how. However, we can observe distortions in tree rings from knots.
Fifth:
This website says that as some trees age, the width of the ring it grows becomes smaller. So, trees may have a high-growth juvenile or youth phase, and a later phase of life with belly fat and hair growing out of its ears. And trouble getting off the ground from a sitting position. And increased interest in bowel movement patterns.
The data graph at this link really has quite an elbow – looks like a scree plot. You have to factor in the elbow at just the right time, or your measures will be thrown off.
Men are at a steadily increasing risk of heart attack across the lifespan. Women’s risk rises, also, but much more slowly. Until menopause. When their increasing risk rate per year climbs. Another data pattern with an elbow.
But you cannot simply cannot have some specific year be the break point for this elbow, if modeling heart attack risk. Because this elbow is menopause. Women go into menopause at differing chronological points. Average age of beginning is supposed to be 51, and most women have beginning of menopause from 45 to 55. Quite a range of elbows. 10 years. 1/7 or 1/8 of entire life span.
https://seattlecentral.edu/qelp/sets/056/056.html
Two problems are shown up here, one technical and one social/?political:
1. Technical. The real history of temperature was not an average of possible but one actual. Each run uses temperatures that are an average of both proxied temperatures and error bars for those temperatures. The ensemble averages out actual highs and lows that had zero error bars. The result is low frequency whereas actual events were high frequency. So the MWP etc easily disappears in the mix and error bars.
This is the same problem for the IPCC scenarios: the actual future will be one pattern, not necessarily anything like the ensemble average.
2. Social/political. The public, including politicians, misread the ensemble as an accurate representation of past temperatures, a specific rise and fall instead of an averaged, educated, or best guess. To them, it shows the Minoan, Roman and Medieval warm periods didn’t exist. They don’t know that one interpretation showed they or one did exist but uncertainties in the interpretations and error bars wiped them out.
This loss of probable short to middle term warm and cold periods in the record is then compared to detailed measured records of the last 160 years that has almost zero error bars and high frequencies. A 50 year high frequency warm event looks like a horrific anomaly and is touted as such.
Maybe not. If you look at the ensemble error bars you can imagine an actual temperature rise and fall that matches the last 160 years – or exceeds it – while staying true to the uncertainties of the data and interpretations.
You will notice that past excessive hot or cold periods are written off as local, while currently they are called global. That could simply be in the nature of data uncertainties and interpretation.
Averages hide data variance. If the real variance was shown, noone would believe the doomsaying!
I am impressed that this ensemble group came up with ONLY 15 schemes.
Recalling those few decades back, when beginning my career in the petroleum exploration business, the joke was that if you gave X geologists the same dataset and asked them to render an interpretive map, there would be X+1 or X+2 … or etc maps.
There is no common era.
If 15 groups come up with 15 completely different answers, then this is not science, these are just guesses. We can’t even test them vs the “correct” answer, so they have the added benefit of likely never being proven wrong. Sure there is measurement error, uncertainties from numerous other factors not modeled and/or no data available, etc., but if the science was sound then most if not all of the groups would be in general agreement. Obviously this technology is not fit for purpose of determining past temperature. It is of course fit for purpose of propaganda and grant farming.
“a more consensual” That’s stupid beyond belief.
Let me translate it:
We therefore recommend the routine use of ensemble reconstruction approaches to provide a more fallacious picture of past climate variability, by the bandwagon fallacy.
Because logic is overrated and climastology must crap on the scientific method with all its might.