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Roy Spencer's paper on climate sensitivity

What the science says...

Select a level... Basic Intermediate Advanced
Spencer's model is too simple, excluding important factors like ocean dynamics and treats cloud feedbacks as forcings.

Climate Myth...

Roy Spencer finds negative feedback

"NASA satellite data from the years 2000 through 2011 show the Earth's atmosphere is allowing far more heat to be released into space than alarmist computer models have predicted, reports a new study in the peer-reviewed science journal Remote Sensing. The study indicates far less future global warming will occur than United Nations computer models have predicted, and supports prior studies indicating increases in atmospheric carbon dioxide trap far less heat than alarmists have claimed." (James Taylor)

Climate scientists have identified a number of fundamental problems in Spencer and Braswell's 2011 study which wrongly concludes that the climate is not sensitive to human greenhouse gas emissions.  One of the main problems with the paper is that it uses Roy Spencer's very simple climate model which we've previously looked at in slip up.

This simple model does not have a realistic representation of the Earth's oceans, which are a key factor in the planet's climate, and it also doesn't model the Earth's water cycle.  One key aspect in the Earth's temperature changes is the El Niño Southern Oscillation (ENSO), which is a cycle of the Pacific Ocean.  Spencer's model does not include ENSO, and he assumes that ENSO responds to changes in cloud cover, when in reality it's the other way around.

There are some other key problems in the paper.  It doesn't provide enough information for other scientists to repeat the study.  When two other climate scientists (Kevin Trenberth and John Fasullo) tried to replicate its results as best they could with the information provided, they found quite different results (see the Advanced version of this rebuttal for further details).  Spencer and Braswell's conclusions also only seems to work using the satellite data set they chose, but Trenberth and Fasullo found that using other data sets also changes their results.

Trenberth and Fasullo also found that when using a few different climate models, the one which replicated the observed data best was the one with a climate more sensitive to greenhouse gases, which directly contradicts Spencer and Braswell's conclusion that the climate is not sensitive to greenhouse gases.

It's also worth noting that the journal which published Spencer and Braswell's paper does not normally publish climate science research.  This may explain how the paper made it through their peer-review system with so many problems.  In the end, Trenberth and Fasullo find that the Spencer and Braswell study has no merit. 

  • The model it uses is far too simple to accurately represent the Earth's climate
  • The paper doesn't provide enough information to replicate their results
  • Their results depend on using one particular data set
  • They assume that ENSO responds to cloud cover changes, when in reality, the reverse is true
  • The study's conclusions are incorrect and unsupportable

UPDATE 3 Sep 2011: Wolfgang Wagner, has stepped down as editor-in-chief of the journal Remote Sensing. Wagner concluded the Spencer's paper was "fundamentally flawed and therefore wrongly accepted by the journal". More here...

Last updated on 1 August 2011 by dana1981.

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Comments 1 to 50 out of 80:

  1. I beg to differ. Spencer has simplified his argument and presents it better in his book "The great global warming blunder." I will counter only three of Trenbert's arguments: 1) how Spencer deduces that sensitivity has been exaggerated, not from models, but directly from satellite data; 2) what is a feedback; and 3) what purpose his simple model serves. 1) Sensitivity may be calculated from measurements of radiative energy imbalance dH/dt and sea temperature anomaly dT, both averaged globally. A linear regression of the former vs the latter yields a slope that has been interpreted as the reciprocal of a sensitivity metric. The basis for this method is the assumption that there is not any other significant forcing on the temperature anomaly than the radiative imbalance. The data are considered to be samples of a linear relationship between only two variables plus a large amount of noise. If there were another significant forcing variable x unacknowledged in this process, there would be an error in this method. A change in dT caused by a change in dx would be mistakenly attributed to dH/dt, making dH/dt more powerful a factor than it really is. That is exaggerated sensitivity. Spencer has demonstrated the existence of such a variable. He has connected the data points in the plot described above in the order of their measurement. This converts a set of points into a trajectory. The trajectory typically consists of a repeated alternation between two forms: a messy, loopy curve and a remarkably straight line. That alone strongly suggests two kinds of process which alternate in strength. Spencer interprets this kind of trajectory as an alternation between the slow radiative process of warming the oceans upper layer and the rapid non-radiative process by which the upper layer creates clouds. Candidates for the non-radiative sources of the latter are ocean currents related to ENSO and PDO, which heat or cool the air and moisten or dry it. Clouds created by these sources vary over time in shielding power unpredictably, causing variation of their shading, which creates a radiative forcing. These clouds are not created by contemporaneous solar heating and cooling. More than one forcing? That creates error. It is on the basis of this analysis that Spencer concludes that sensitivity has been exaggerated. 2) Trenbert denies that the second process described above is a forcing. Spencer follows the convention of engineers saying that there is one dependent variable, T, in this system. Feedback is a temperature change caused by a temperature change. Everything else that affects temperature is forcing. Clouds are forcing in this nomenclature. But that is irrelevant. Call it what you will, it exaggerates sensitivity. 3) Spencer's little model is not intended to model the atmosphere of the earth. It is a mini-model that shows that a system of a radiative forcing and a non-radiative forcing creates trajectories of the kind that can be seen in the satellite data, plotted with connections. It is a demonstration of the concept. It is especially useful in that it demonstrates how a simple system with given negative feedback can produce results that appear to involve positive feedback.

    [DB] Your #1 merely unsupportedly reiterates Spencer's mantra that clouds cause ENSO. This is not supported by the peer-reviewed literature published in reputable journals.

    Your #2 is specious. Climate science is what we are discussing, not engineering.

    Your #3 is indeed a demonstration of concept, but one not supported by the literature (as noted above) nor by reality itself.

  2. #1, to make a small addition to the moderator's comment, you have to ask yourself the following question: If Spencer is right, why do a whole range of estimates of climate sensitivity from palaeoclimate observations contradict him? Read Knutti and Hegerl 2008, and the SkS summary here. The thing about palaeoclimate and geological estimate of sensitivity is that they already include the total forcing by clouds and all other factors. Essentially, whenever we estimate climate sensitivity, whether from geological events millions of years ago, from the last glacial maximum, the Holocene, the last century, or recent volcanic eruptions, the results tend to be in the range about 2 to 5C per doubling CO2. If Spencer was right, an awful lot of observational evidence from a lot of different, independent lines of enquiry, quite apart from model data, has to be wrong. Additionally they all have to be wrong in the same direction, by approximately the same amount. Likely? And you'd still have to postulate a mechanism by which we have had glacial and interglacial episodes generated from small Milankovitch forcings. What is much, much more likely is that Spencer is as wrong on this as he has been on quite a number of climate-related matters.
  3. @Moderator 1. The reason I say that some clouds cause, not global warming and not ENSO nor PDO, but inaccurate measurement of sensitivity, is that they vary the temperature anomaly in time and are not caused by the current energy imbalance. In this way they reduce the regression slope, and thus corrupt its interpretation. 2. Nevertheless, what is of interest in this question is the idea that a rise in temperature reduces cloud cover and further increases temperature. Climate science does find this crucial for water-vapor feedback. 3. The little model demonstrates a mathematical fact, which is already obvious to students of statistics, namely that you cannot compute the sensitivity to one variable if another hidden variable is varying the output. @skywatcher - Data from the past includes, as you say, forcings of unknown and perhaps numerous sources. As we cannot measure these forcings now. That means that we cannot remove their effects for the purpose of estimating feedback. That is why it is so valuable to have satellite data, which gives us the forcings as well as the anomaly. Consider how data were adjusted to compensate for the eruption of Mt. Pinatubo. We can't do that for ancient data. Failure to correct for forcings other than the energy imbalance always affects the sensitivity in the same direction: it lowers the slope and raises the sensitivity. Also, science is not a horse race. Let us not try to handicap the jockey.
    Response: TC: Uncle Ben, if you do not stop double posting, I will start double deleting.
  4. Uncle Ben: "3. The little model demonstrates a mathematical fact, which is already obvious to students of statistics, namely that you cannot compute the sensitivity to one variable if another hidden variable is varying the output." Welcome to the geophysical sciences. I hope you had a nice stay in the math department. Every day, you manage to make decisions based on intuitive modeling where one or more variables are unknown. You've managed to live, so far. You've probably actually learned from this daily type of intuitive modeling. You've probably made important decisions based on weather forecasts, which use the same type of modeling. The point is that you can indeed calculate sensitivity in a complex system; you just can't calculate it with the precision of a closed mathematical system. Roy knows that. You should know it. And the unknown variable in this case is not all that unknown. I'll wager that you yourself won't accept certain values for it.
  5. DSL: " The point is that you can indeed calculate sensitivity in a complex system; you just can't calculate it with the precision of a closed mathematical system." I agree! In fact, Spencer has provided us a way to improve the estimate of sensitivity. By separating the trajectory of dH/dt vs dT into segments in which the effect of dH/dt and the non-radiative forcing that creates clouds in the absence of strong dH/dt, he has been able to estimate the slope of the regression of the latter. He finds that the slope is about 6 in the usual units, as opposed to 2.5 using the combined data. This yields a sensitivity low enough to show that the feedback from dH/dt causes is negative. Doubling CO2 then is seen to cause only 0.5 deg. C of warming. Not much calculation is needed, in fact. If you take the trouble to look at his plots, you will see that the straight-line segmenmts are numerous, parallel, and obvious. It is quite convincing. It is their slope which gives the sensitivity to dH/dt. The plots are so clear in showing the straight-line segments that the precision is much higher than that of the widely scattered estimates of sensitivity found by other means. We know now why they are widely scattered. A variable has hitherto been ignored.
  6. #3 - a handwaving attempt to dismiss the evidence of a whole range of branches of science, doesn't cut it for me I'm afraid. Re-read Knutti and Hegerl. Just one example: With low climate sensitivity, how do you get glacial-interglacial cycles, which are clearly (from timing and frequency) forced by the small Milankovitch orbital variations?
  7. Agreed. Without evidenciary links to supportive works in the literature, it's an exercise in climastrological mathturbation.
  8. @skywatcher " With low climate sensitivity, how do you get glacial-interglacial cycles, ..." I have no idea, but climate is complicated. If what is offered here is mere handwaving, why was Mt. Pinatubo's contribution to temperature variability so laboriously removed from the data when trying to measure sensitivity? Is it not demonstrated in that exercise that removing a competing source of variability is important and reduces the calculated sensitivity? And when Spencer removed the forcing effect of cloud variation from sources other than dH/dt, he reduced the apparent sensitivity result and permitted a PRECISE measurement of the sensitivity. That has never been done before. The idea of extracting more information from satellite data by noting the time sequence of the data points is a novel and valuable contribution that eventually will get the appraisal it deserves. (If you quip "none," history will judge you.) @Bailey "Without evidenciary links to supportive works in the literature, ..." Isn't the correction for recent volcanic forcing in the literature? The removal of extraneous variation from the ancient data is not in the literature because it is impossible. It is too late. The impact on sensitivity measurement has not been adequately realized. Maybe climate scientists need to brush up on statistics. You can't argue with mathematical facts.

    [DB] The volcanic damping effects on temperature due to aerosol release quickly fade out, even on the non-geologic timescale (with notable exceptions, such as the Siberian Traps).

    In the paleo record, volcanic effects quickly fall into the obscurity of noise in the data at the resolutions available. Thus their effects are already compensated for by the climate system. Perhaps more study of the paleo record for edification purposes is in order.

  9. Uncle Ben: Interesting paradox. You represent that 'a little model' should be taken seriously, as it and it alone somehow correctly captures 'mathematical facts'. Yet when questioned as to how the little model reproduces some of the largest variations in the record, your reply is 'climate is complicated.' Nicely contradictory. Which position do you actually hold? Because you cannot simultaneously hold both. Perhaps instead of dismissing more complete models so casually and accepting Spencer's reductionism, you should take the time to actually learn what the more realistic models entail. You might then retract your 'need to brush up on statistics' allegation, which is utterly unfounded and without merit.
  10. Uncle Ben @8, when somebody says "You can't argue with mathematical facts", they are setting up to deceive you. Maths is a formal language. Like all formal languages, it has no innate interpretation. In order to say something - anything - about the world with maths, you need to set up an interpretation, and that interpretation can be false, contradictory or deceptive just as much as any statement in English. When somebody tells you that maths can't lie, their sole purpose (if they are not simply foolish) is to draw your attention away from the potential fallibility of interpretation. There is a reason why lies, damned lies and statistics represents a progression.
  11. @DB I bow to your superior knowledge of the climate effects of volcanic eruptions. But they are mentioned just to illustrate a point. If you don't know the forcings, you can't meaure the feedback. Volcanic eruptions are not the only conceivable extraneous focing. @Tom You can prove the point yourself. Make two data sets, (1) more or less linear values of y vs x, and (2) a random set of values of z vs x covering the same range. Compute the regression coefficient of y vs x. Call it ax1, a constant. Combine the two data sets into one, their union. Call the regression coefficient ax2. With any reasonable data, you will find that ax2 < ax1. In this example, y is the effect of solar warming of the atmosphere and z is the effect of ocean-current warming of the atmosphere. Imagine that you measure ax2 innocently believing that you are measuring ax1. That is the blunder that Spencer is talking about.
  12. @muon counter (belately) You (and many others) seem to think that models are the only business of climate science. Models are an attempt to guess the answer and evaluate it by comparing its results with the temperature record. The attempt is based on one's understanding of the physics of the problem. Thus if you think that clouds produced by ocean currents, not directly by the sun, "average out" and do not affect the results, then your models may compensate for the error by finding an exaggerated sensitivity to the variable you think is more important. I say "error" because in the measurement of sensitivity, it is not the cumulative effect of clouds that is important. It is the variation in effect. Clouds vary greatly over time in their effect on temperature. Measuring sensitivity depends not on the cumulative effect but on the variance of the effect. The mean may be zero, while the variance is not. In fact, an extraneous, varying effect reduces the correlation of solar forcing with ocean temperature, and consequently implies a high sensitivity to the solar forcing. This is an error. A model can use exaggerated sensitivity to compensate, but that departs from reality. But climate science has another tool: direct measurement. If you understand Spencer's book, you will see that he has found a way to isolate the inputs to warming and calculate sensitivity WITHOUT MODELS. He disambiguates the total forcing into two kinds according to the speed of the effects: Warming the ocean by the sun is slow; warming of the air by oceans is fast. I'm not going to paraphrase the whole book for you. If you want to keep up, buy the book "Greatest Blunder" for short. (I get no commission.)
  13. Uncle Ben, You are obviously confused about the nature of the Skeptical Science web site. At this site we discuss peer reviewed scientific data. Spencers' book has not been peer reviewed, so it does not count. If Spencer thought his ideas were worth the paper they are printed on he would submit it for publication. Since he has not, obviously he thinks the idea will not stand up to rigorous review. This book is no different than a blog post or opinion piece in the newspaper. If you want to support your views here, please cite peer reviewed data. You are wasting our time arguing by using your opinion of an opinion piece. Please use peer reviewed material or no one will take you seriously. When you make a reference to a paper you must cite the page that supports your position. Saying "If you want to keep up, buy the book" means that you are unable to identify the section of the book that actually supports your position. Why should I read a book when you cannot identify the part that supports you?
  14. Uncle Ben#12: "You (and many others) seem to think that models are the only business of climate science." Ah, an assertion without any evidence to back it up. If you review the archives, you will note I hardly ever offer opinions pro or con about models. However, this is a modeling thread and you came in defending the merits of Spencer's 'little model.' I merely pointed out the contradiction inherent in your position. That contradiction still stands. One cannot hold two sides of an argument - simple model is good v. 'climate is complex' - if one wishes to stand on scientific principle. Unless one's address is in Deniersville, that is. "But climate science has another tool: direct measurement." Yes, that is indeed the business of many climate scientists. If I recall correctly, that is to a degree Spencer's business as well. Of course, no one can be sure, as he claimed to be a lobbyist... and now has books to sell. So much for objectivity. "...consequently implies a high sensitivity to the solar forcing. This is an error." Are you now suggesting (or saying that Spencer suggests) that climate does not have high sensitivity to solar forcing? That is very interesting, as it flies in the face of the stipulations of the solar-modulated cosmic ray crowd. "... he has found a way to isolate the inputs to warming and calculate sensitivity without models." --all caps removed Does Spencer use, in any way whatsoever, the satellite temperature record? If so, he is using a model that converts microwave transmission to atmospheric temperature. Hence, no such isolation is possible.
  15. @muon counter "[T]this is a modeling thread and you came in defending the merits of Spencer's 'little model.'" I thought this was a thread about Spencer's proof that climate sensitivity has been incorrectly estimated and how to fix that. He doesn't need any models. He measures sensitivity directly. I came in here to talk about how Spencer did that. It was not to defend any model. Models are not needed when direct measurement is possible. "Does Spencer use, in any way whatsoever, the satellite temperature record? If so, he is using a model that converts microwave transmission to atmospheric temperature. Hence, no such isolation is possible." You have missed something. This is the good news. Isolation is possible. You missed the part where I explained that. He plots the dH/dt vs dT points connecting them in the order of time of measurement. This coverts points into trajectories. Examination of the trajectories shows plainly that they consist of segments alternating between curly parts and very straight parts. The curly parts indicate a slow process, such as the gradual warming of the ocean by the sun; the straight parts indicate a quick process, such as warming the lower atmosphere by ocean currents, not the sun. The difference in speed occurs because of the 20:1 ratio of heat capacities. It is an observable phenomenon that in all these plots, the slopes of the straight lines are the same. They imply a sensitivity to doubling of CO2 of only 0.5 deg C. They also show that the satellite measurements contain hardly any noise. What has been thought to be noise is the contribution of the curly parts. The straight parts are very straight. @Michael Brewster (-Conspiracy theory claims snipped-). Anyone can reproduce these claims if they have access to the satellite data including the times of measurement. (-Off-topic snipped-). (-Inflammatory tone snipped-). We will see. (-Conspiracy theory claims snipped-). (-Trolling snipped-).

    [DB] Please familiarize yourself thoroughly with the Comments Policy of this website. Future comments constructed such as this one will be deleted in their entirety.

    "He doesn't need any models."

    That is right up there with this.

  16. Uncle Ben, your comment "Will any warmist check Spencer's method?" really is rather funny. Perhaps you didn't note who wrote the "advanced" rebuttal on this theread, one Kevin Trenberth. The same Trenberth from Trenberth et al 2010, which rebuts one of Spencer's core arguments. The post is essentially a reporoduction of the post by Trenberth and Fasullo at RealClimate (Mods - should that connection be highlighted or am I not seeing the link?). Barry Bickmore has also deconstructed Spencer's models here, and also the modelling in his book here (more on Spencer's book here) These issues have been repeatedly looked at by those professionally competent to do so, and every time Spencer's little models have been found desperately wanting. Spencer's in the same position as you are, having no clue how to generate the ice ages "... it is reasonable to suspect that the ice ages and the interglacial periods of warmth were caused by some as yet undiscovered forcing mechanism. (p. 69)" In the real world, they are rather less of a mystery. Claims of publication supression are perennially comical - if so, how did Spencer and Braswell get published? Lindzen and Choi? The laughable, lamentable McLean et al? Bad papers get published, even in good journals, quite regularly - and for papers that are even worse, there's always Energy & Environment. And funny how claims of supression come from those who are demonstrably doing bad science (not just contrary science, but demonstrably bad). I'm not sure what you're on about in regard to Mount Pinatubo. "Laboriously removed"? (source?). It's actually been used to estimate climate sensitivity too (e.g. Bender et al 2010)!
  17. Uncle Ben#15: "Models are not needed when direct measurement is possible." I'm sorry, we must have a vastly different understanding of the words you've used: Your #1: "A linear regression of the former vs the latter yields a slope that has been interpreted as... " A linear regression is a model. Any interpretation based on slope is a model. "The basis for this method is the assumption that... " Assumptions are part of the modeling process, necessary to develop a simplification that may then yield to analysis. "Spencer's little model is not intended to ... " That is a direct contradiction to your "It was not to defend any model" claim in #15. "The cardinals who hassled Galileo... " Ah, the Galileo gambit. There is no necessary link between being perceived as wrong and actually being correct; usually if people perceive you to be wrong, you are wrong. ... They really do forget the part where they have to prove themselves right in order to be like Galileo. And still no answer to skywatcher's very relevant question. I learned somewhere that when an assumption leads to an untenable conclusion, the assumption is usually incorrect.
  18. My final post. @muon counter "Linear regression is a model" To me a model is an attempt to build a system that will re-create the temperature record albeit with some adjustable parameters. A linear regression is just a calculation. Yes, I was aware that the basis for the "Advanced" discussion was owed to Trenberth. Yet he and Bickmore both center their attack on what I consider a footnote -- a simple model whose purpose is to show how even a simple model using the right sensitivity can accomplish a lot. Its simplicity is a virtue, not a handicap. In their defense, I acknowledge that the Spencer and Braswell paper was much harder to follow than the argument in his book. The book plainly shows the time-sensitive plots, which I find so mind-bending. If the "little model" had been completely left out of Spencer's writings, he may have avoided a distraction. The main point of the book is to show how to disambiguate periods in which the sun is the stronger forcing from periods when ocean currents (ENSO and PDO effects) are forcing strongly by means of cloud variability. I am astonished at how little attention has been directed at this novel contribution. To me, that is worth a Nobel Prize. It is method of analyzing data that "muon counter" considered as impossible. Anyone who plots the satellite data points connecting them in order of measurement will be blown away by what he sees. It has been illuminating exchanging views with all of you. It has shown me how hard it is to change the paradigm. We will all come together someday. Peace.
  19. @17 Linear Regression is not a model, it is a statistical method for analyzing data and to represent that data as an equation. Whether that equation is or isnt then used in a model, is an entirely different question, but linear regression in itself is not a model.
  20. Uncle Ben, you appear, from your writing here, to be someone who has based their entire opinion of this subject on your reading of a single, non-peer-reviewed, book. A book within which Spencer was free to publish whatever he liked, including the accusations of supression, heck he would have been free to attribute global warming to pink leprechauns were he in the mood! While books can indeed be informative, there is great freedom in writing a book to publish unsubstantiated or erroneous claims, a freedom that is generally restricted by the scientific peer-review process. Indeed, that is the purpose of peer review. Peer review does not eliminate all the bad science, but it weeds out the most obviously wrong/unsupported claims. It is a small step to go from Spencer's book to Gavin Menzies, who annoyed historians by publishing wild, unsupported claims about the Middle Ages exploits of the Chinese, and only a small further step to pure fiction a la Dan Brown. As such, your writings here stand as a cautionary tale for those who would base their understanding of a sunbject on a single source (Spencer) or single line of enquiry (tropical cloud models). Fortunately, our understanding of climate science is based on a great breadth of empirical data of human fingerprints on climate, including empirical evidence of positive feedbacks. This evidence comes from a whole range of branches of science, including but not limited to physics, chemistry, palaeoclimate, oceanography and atmospheric science. It provides a coherent picture, without gaping holes in our understanding, such as demonstrated above with glacial-interglacial cycles. A picture supported by, but not dependent upon, the models, and a picture largely avoided by Spencer.
  21. Uncle Ben I understand that all science must stand up to scrutiny and am not afraid to read contrary views. Is there a link with a concise representation of the satellite data that I can then objectively read?
  22. @Delmar Your rational response persuades me to break my promise not to post here anymore. I cannot provide a link as you request, but I can offer a ten-minute read that may or may not entice you into deeper investigation. Borrow or steal a copy of the Blunder book and look at p.98, fig. 22. This is a plot of the kind I have been describing. See the regression line of the points taken in the conventional way (solid line, slope 2.5). Then see if, among the scattered connection lines, it jumps out at you that half of them are all parallel. It doesn't take a linear regression to estimate their common slope as about 6.0 (dashed line). Ask yourself if this is not something new. Why should there be hidden in all the presumed "noise" of the satellite data so many connection lines all having the same slope. Is nature trying to tell you something? If $25 is an obstacle, I will buy you a copy of the book if you can somehow send me your address. You can find my email address on my profile in alt.globalwarming. Use a "reply to author" link on any of my posts. @Skywatcher Thanks for attempting to broaden my education. I have read Hansen and many articles on both sides. I am a retired physicist (Ph.D. Johns Hopkins) and many years of teaching and research, but in low temperature properties of metals, not in climate science. I have some 25 published experimental papers and a text on vector calculus, now out of print. I was a believer in global warming until Michael Crichton's book, State of Fear, shook me up a bit. Further reading on both sides led me to Spencer. I have observed witch hunts before, and the vehemence and violence of the attacks on him and the ignorance exhibited by even eminent authorities in the "concensus" persuaded me to study him deeper. Thank you for the serious post. I wish we could have some deep conversations. I came to Skeptical Science looking for a more serious exchange than I found possible on the alt.globalwarming newsgroup, populated largely by undisciplined children. With a few exceptions, the exchanges here have been closer to science than to the flaming in the newsgroup. I was shocked by the post of someone who said that SkS was devoted to one side, but the follow-up has been somewhat reassuring.
  23. Uncle Ben, you sound like a potentially reasonable peron, but seriously, ask yourself the following questions, and ask them with an open mind: Does reading "The Da Vinci Code" shake to your foundations our understanding of the history of Christianity and reveal that Jesus' great-great-great granddaughter is living among us, or do you accept it is a work of fiction? Does reading "Jurassic Park" make you think that we can actually recreate dinosaurs from 65 million-year old DNA? Does reading "Congo" amke you think there are intelligent, sentient, trained gorillas living in the forests of Virunga National Park? Does reading "Twilight" (or "Dracula") make you think there are vampires living among us? Two of these four very readable works of fiction were written by Michael Crichton, a medical doctor with no more climate science expertise than I have of dentistry. Why should reading "State of Fear" make you think that climate skepticism has any sound foundation? Crichton was very good at his trade - but he was a successful writer of fictional stories that seemed almost believable. I'm sorry to think you might have been fooled by him. I don't think the recreated dinosaurs, climate skepticism, or dangerous sentient gorillas are plausible, given the current state of knowledge, and certainly Roy Spencer has not succeeded in presenting a case either. Go learn about the mountain of evidence that underpins our understanding of climate science (the links above contain a wealth of good references) - and you could do worse than start with Spencer Weart's excellent history of our understanding of the Greenhouse Effect, and also take an hour out with the great Richard Alley to learn why CO2 is the biggest control knob on climate. You have enough physics to understand the robustness of the basics of the theory, and I hope you have enough open-mindedness to realise that if there's a witch hunt (enter stage left Ken Cuccinelli and Sen Inhofe), it is against your former colleagues, the scientists, not with them.
  24. As an addendum to the last post, it should be noted that climate scientists, without exception among the many I have met along the way and without exception among those who are asked, want to be wrong! It's not a cheering thought that we're changing our climate faster than has ever happened in the palaeocliamtic record. It would be much more comforting if something magical was to come and cancel out the radiative effect of the excess CO2, add some alkalinity to the oceans, and stabilise the mass balance of the great ice sheets. Sadly, there is no evidence for this magic that I hope to read about every single day.
  25. @Skywatcher I appreciate your post. No, Crichton did not persuade me, but he did present some ideas that were new to me. The result was that I started digging deeper. Onl later was I persuaded that there was something going on here with the concensus that was not right. If you want to be wrong (which I understand completely) you should spend ten minutes on the exercise I just recommended to Delmar. (I am not offerring to buy everyone a book, but that is another matter.) Your scientific curiosity must be aroused by the hint of a new phenomenon. You do understand that the technique displayed in Spencer's plots has not been seen before in this field. He has, at least, shown that there is more information in the dH/dt vs dT plots than has previously been recognized. If "muon counter" considered it impossible, someone should be able to poke a hole into the claim that it has been done.
  26. Uncle Ben#25, While I appreciate the continued double-quoted shout-outs, I am not sure they contribute to productive discussion. If you are curious as to the origin of my login name here, I do indeed count muons (in my spare time). "You do understand that the technique displayed in Spencer's plots has not been seen before in this field." No. Others have tried to prove their misconceptions by looking at short term changes alone (notably, that year-to-year changes in atmospheric CO2 were supposed to show a natural source). Tamino did an excellent analysis of this type of mistake (which Spencer made as far back as 2008): He’s based his estimation of climate sensitivity on time spans which are so brief that feedback (in the usual sense) in the climate system doesn’t have time to operate! If you eliminate feedback (in the usual sense) from consideration, you’re not going to get a realistic estimate of climate sensitivity. After some searching, a graph similar to the one you describe as so revolutionary is shown here: -- source In this graph, many 'segments' are indeed parallel. But what does that signify? Rather than declare that 'Mother Nature is trying to tell us something,' look at the graph itself. In a plot of change in flux vs. change in temperature, we are looking at derivatives. What is the significance of the slope of a derivative in this context, except as a very effective means of removing the longer term trend? A derivative, after all, is a high-pass filter. And in climate contexts, high frequency equates to noise. Note: If this is not the type of graph you are describing, my apologies. There are numerous criticisms of Spencer's method, both on the source page for the graph above and on the RealClimate review of Spencer's blunder. At the minimum, Spencer somehow equates global radiation to ocean-only temperature change, presents (without saying so) a very short time span of data and emphasizes monthly variation (which of course, obscures the longer period terms). To make matters worse, Spencer's own words betray a certain lack of scientific objectivity: I find it difficult to believe that I am the first researcher to figure out what I describe in this book. Either I am smarter than the rest of the world’s climate scientists–which seems unlikely–or there are other scientists who also have evidence that global warming could be mostly natural, but have been hiding it. So let us lose the Galileo references, the 'witchhunt' fears and the appeal to 10 minute exercises. Let us lose the proclamations of Nobelity (which seem to be prevalent only on the pages of WUWT). I do agree that we must always be on the alert for hints of paradigm change. But this wasn't it.
  27. Uncle Ben wrote:
    Then see if, among the scattered connection lines, it jumps out at you that half of them are all parallel. It doesn't take a linear regression to estimate their common slope as about 6.0 (dashed line).
    Uncle Ben, humans are very good at seeing patterns, because that's a crucial survival skill. It is such an important survival skill that humans are biased toward seeing patterns in samples of data even when those patterns do not exist in the population of data from which those samples are drawn. That was a good bias in our evolutionary history, where usually there was a low cost of acting on the basis of perceived patterns that are not really in the population, compared to the high cost of failing to act due to not recognizing patterns that really are in the population. For example, a shrub rustling could indicate a bear. Changing course to avoid that shrub has the slightly negative expected value of missing whatever food might be in that shrub (low probability of there being more food in that shrub than elsewhere, low value of food in that shrub versus elsewhere, even if it is in that shrub). In contrast, not changing course has a large negative expected value (fairly low probability of being killed by bear, but very expensive cost if true). The inferential statistics that you so casually dismissed are crucial tools for mitigating those biases in judgment based on visually detecting patterns. All that long ago was well established in the empirical science of judgment and decision making. For example, Tversky and Khaneman (1971) called it "belief in the Law of Small Numbers." They found it existed even among 84 scientific research psychologists all of whom had extensive training and experience to avoid that bias. So I'm not picking on you, I'm simply pointing out how difficult it is to counteract that bias. You can't really avoid that bias, because it's a core part of being human. Instead you must acknowledge the bias's existence and consciously override your instinct despite what your gut is telling you. There are some utterly reliable examples of judgment and decision problems whose correct answer violently disagrees with people's gut, to the extent that when I try to force my gut to match my head, I literally start to feel nauseous despite my years of training as a decision researcher. I find that fascinating. I suspect you, too, will find it fascinating, so here are some links to get you started; I suggest dipping in to the references on these pages, especially the peer-reviewed publications, instead of stopping after reading just these particular pages: the clustering illusion in the Skeptic's Dictionary, the clustering illusion in Wikipedia (remember, don't just trust Wikipedia--read the referenced papers), and apophenia in Wikipedia (I'm not at all suggesting you suffer from apophenia; I'm linking there because it has a wide range of references relevant to a particular judgment bias.) Being disciplined in doing that overriding of your gut is a big part of scientific training in fields that inherently have messy data. Perhaps the scientific field from which you are now retired had relatively tidy data and so does not require so much vigilance against that bias. But you need to recognize that your expertise in one narrow field of science does not transfer to all other areas of science.
  28. @muon counter I suspected that you are a physicists from your username. The Tamino reference is quite interesting. Thanks. He does not seem to accept that the slope on the dH/dt vs dT represents inverse sensitivity. I thought that was well accepted. He complains that a mere 8 years is too short a time to measure feedback. Doesn't that depend on how fast the feedback is? Feedback to the heating of the ocean, if any, is certainly quite slow. That is why what I have called the curly parts curly. Ocean currents are affected chaotically by many things on the way to equilibrium. But it is certainly helpful to have the usual (non-time-connected) plots recognized as showing points that are certainly not at equilibium, and in that case there is no reason to expect a proportionality between rate of heating and temperature. But the heating of air by warm water is quick. The ratio of specific heats of air and water is quite small. That is why the segments are straight. So the 8 years of data are plenty for the feedback of cloud effects. The parallel segments measure the (inverse) sensitivity at equilibrium between rate of heating by oceans of the atmosphere. Of course, the reason for using the brief span of satellite data is that we have the dH/dt data and the time of measurement. The temperature data inferred earlier is informative for temperature, but we cannot estimate the forcings that caused it. This makes it hard to infer sensitivity. Regarding ice ages and sensitivity, here we are talking about feedback of a different kind. Feedback to albedo is certainly strong and positive. @Tom Dayton Some decisions require statistics and some do not. If you measure each line slope, you can do the statistics and find the std. deviation. But some things are actually obvious. If you look at the plots in the Blunder book, you will see. In physics, the half-serious view of statistics is, if you need statistics to make your point, improve your experiment. That one has tongue in cheek, but there is some truth to it. I have taught statistics and have examples where they are needed.
  29. 28, Uncle Ben, Your worshipful attitude towards Spencer is wholeheartedly unskeptical. Especially when the flaws are so obvious. Muoncounter has already quoted the single most important fact, from Tamino:
    He’s based his estimation of climate sensitivity on time spans which are so brief that feedback (in the usual sense) in the climate system doesn’t have time to operate! If you eliminate feedback (in the usual sense) from consideration, you’re not going to get a realistic estimate of climate sensitivity.
    That's it, right there. What Spencer has done is equivalent to proving that you aren't aging by demonstrating that you weren't more prone to illness after a week of elapsed time. It's meaningless. When you add to that the other problems with his report, the whole thing is a waste of time (have you read the criticism above? Why do you put so much effort into lauding him without addressing those criticisms?).
  30. 28 - Uncle Ben A couple of things. In tamino's post he exactly equates sensitivity as the inverse of the slope and derives, via the method, and says; "estimated climate sensitivity is 1/1.553 = 0.644 K/(W/m^2), very close to the true value 0.667 K/(W/m^2)." What's the problem with that? Did you read the article? If not, shame, because his commentery on Spencer's error relates closely to your insight: "the half-serious view of statistics is, if you need statistics to make your point, improve your experiment". As you clearly know, that is said because statistics is only important if your are dominated by statistical or systematic errors. A better experiment could reduce the former (more data) or the latter (less measurement errors). Now, as I read it, it is exactly Tamino's point that if you look to closely (to short a time scale) you will be dominated by the systems internal dynamics. as he says "He’s based his estimation of climate sensitivity on time spans which are so brief that feedback (in the usual sense) in the climate system doesn’t have time to operate!" I'm pretty sure if you read Taminos post as a statistician (indeed, as one statistician to another!) rather as attacker/defender of some bit of work; you will see his insight.
  31. Uncle Ben, you did not explicitly confirm or deny that the graph shown by muoncounter above @26 is the type of graph to which you refer. Could you please do so. Could you also do the same for the following graph: Quite frankly, your discussion to date has been essentially meaningless because you have not provided an example of the graph which is central to your case. Without your explicitly providing such a graph, or explicitly acknowledging some example, you give the impression of intentionally keeping the center piece of your discussion carefully hidden to avoid criticism.
  32. @Sphaerica 29 and Les 30. (Complaint about only 8 years of data) Friends, you would not say this if you had been able to read my response to muon counter at 28. (1) Three seconds is enough time to measure audio feedback in an auditorium. (2) One month is enough time to measure temperature feedback from ocean currents to the lower atmosphere. (3) One year is surely not enough time to achieve equilibrium to the solar heating of the top layer of ocean. @Tom Yes, this is kind of plot I have been talking about. I have been reluctant to post copies of the plots for fear of copyright violations. My motives were fear, not craftiness. :-) (How we suspect each others motives! But the answer to suspicion is openness. I have nothing to gain by trying to fool anyone. My personal interest is in chasing skirts.) This plot is a little harder to recognize than the one Tamino published, but you can still distinguish the straight parts from the curly parts.
  33. "I find it difficult to believe that I am the first researcher to figure out what I describe in this book." -- Dr. Roy Spencer If his "discovery" were valid, why did he publish it in a book? Science is published in science journals. "Either I am smarter than the rest of the world’s climate scientists--- which seems unlikely--- or there are other scientists who also have evidence that global warming could be mostly natural, but have been hiding it." --- Dr. Roy Spencer Fallacy of false dichotomy. (Dr. Spencer's statement is identical to ones some Creationists have made.) There are other explanations: 1) Spencer could be mistaken; 2) Spencer could have cherry-picked his data. 3) Spencer is so incompetent that he just accidentally left out of his study all of the evidence that refutes his desired conclusion. It seems hyper unlikely to me that Spencer accidentally left out more than half of the data available, and accidentally excluded the best of the data---- which, if he (they) had left in, would have shown his conclusion about climate sensitivity wrong. If I had done this in high school the teacher would have graded my paper an "F," and then castigated me for lying.
  34. 32 - Ben. I did read your post - clearly, better than you read Taminos! which clearly demonstrates which resolutions are appropriate to demonstrate compliance with known science and when the data is being mis-analyses. I've no doubt you've had experience, when teaching, if people finding features due to oversamplung... Again I plead with you to use your statistics insight!
  35. @les 35 Les I am willing to try to answer your questions regarding Taminos post. I found a list of complaints as follows: "Spencer does it “without going into the detailed justification” by: ■Ignoring data from polar areas, where most of the climate change has occurred.(1) ■Comparing global radiation data to ocean temperatures.(2) ■Pretending that 7 years of satellite data is a sufficient time span for climate analysis (try 30 years).(3) ■Restricting his plot to just month-to-month variation.(4) ■Using only monthly temperature changes that were greater than 0.03°C.(5) ■Ignoring decades of independent empirical studies that conclude that climate sensitivity must be somewhere between 2.3 to 4.1°C.(6) ■Sweeping away the 0.6°C warming over last 100 years as natural (therefore a similar estimated rise for this century must also be natural).(7) ■Ignoring the reality check that ice ages are impossible if CO2 sensitivity is as low as he declares.(8) "What does Dr. Spencer end up with? I mean besides the WUWT comments declaring him a shoo-in for a Nobel Prize. He ends up with an artificial statistical correlation with no physical explanation to support it." And I remember among his 3 posts titled 'Spencers errors" I think in which he claims that the ratio of two derivatives means nothing, IIRC. It is this last that I commented on and responded to, but three long posts are too much to search through without printing the out. If you can send me a link, it would help. His name does not appear on these posts, so I am relying on the words of commenters that they are Taminos. Am I mistaken? Among the bullet points, I have already rebutted some. Would you let me know which bother you the most and I will try to answer, if I can. You can refer to them by number.
  36. 32, Uncle Ben,
    (1) Three seconds is enough time to measure audio feedback in an auditorium.
    (2) One month is enough time to measure temperature feedback from ocean currents to the lower atmosphere.
    That's not a feedback, that's simple heat transfer.
    (3) One year is surely not enough time to achieve equilibrium to the solar heating of the top layer of ocean.
    Why? Because you say "surely"? Your answer he is completely nonsensical. You also dodged my last questions. Have you read the criticism above? Why do you put so much effort into lauding him (Spencer) without addressing those criticisms?
  37. UncleBen#32: There are some problems with your feedback analogies. 1. 'Three seconds is enough time' to identify audio feedback - audio frequencies are in the 100s to 1000s of hz. A few seconds represent 100s to 1000s of samples, which is indeed sufficient. However, seven years of monthly data = 84 samples at best; from the figures presented above, it is not clear how many of these are responding to the supposed small feedback. That raises a significant possibility for aliasing. 2 and 3 are both unsubstantiated assertions on your part. If you wish to play by the rules of this house, provide references for your claims. As to your 'rebuttals' thus far, permit me to say, I have not seen any convincing evidence other than your assertions. That we are even discussing a study based on monthly changes in a climate science context already places this entire idea on thin ice. However, it would be helpful if you would focus on the objections you deem #6, 7 and 8; these are substantial - and have not been rebutted.
  38. Uncle Ben @ 18 says:
    I am astonished at how little attention has been directed at this novel contribution. To me, that is worth a Nobel Prize.
    That raises two interesting questions:
    • In what field of endeavour should he be awarded the prize?
    • What are the criteria for earning a Nobel?
    As to the first question, I am guessing the nomination would be in the field of physics, but could it be literature on the basis that Spencer's hypothesis is in the form of an imaginative, published document? (The Nobel prizes are in the fields of physics, chemistry, peace, physiology or medicine, and literature; there is an additional prize, the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel.) For the second question, one source I looked at quoted from Nobel's will:
    The whole of my remaining realizable estate shall be dealt with in the following way: the capital, invested in safe securities by my executors, shall constitute a fund, the interest on which shall be annually distributed in the form of prizes to those who, during the preceding year, shall have conferred the greatest benefit on mankind. The said interest shall be divided into five equal parts, which shall be apportioned as follows: one part to the person who shall have made the most important discovery or invention within the field of physics; ...
    As can be seen, the important criterion is to bring a great benefit upon mankind, through an important discovery or invention. This is where it gets sticky for Spencer: it would have to be proved that he had made an important discovery and that it brought a great benefit to mankind. If his hypothesis were correct, it would certainly be important, but would it bring a great benefit? I suggest that that would depend upon how it changed the progress of our civilisation, or the welfare of our population. Arguably, if Spencer had proved that the Earth is not warming, then it could be said that a monetary benefit would accrue in the form of wealthy nations not having to reduce their CO2 emissions and a psychological benefit would accrue in the form of the removal of significant worry for those who currently accept the theory of AGW. Would that be enough to justify a Nobel? I am not qualified to judge. On the other hand, if Spencer's hypothesis has been demonstrated to be junk science and if his paper does not have great literary merit, we can save the Nobel committee the trouble of deciding these questions. I guess it is up to his followers to nominate his work for a prize and see what happens. Perhaps Anthony Watts could start the ball rolling, as Spencer supporters seem fairly thick on the ground at his blog.
  39. Uncle Ben @32, thankyou. In light of your response, I want you to consider the following graph derived by the same means, but using a different data set to that shown in my post 31: If you recall, in your post 5, you wrote:
    "Not much calculation is needed, in fact. If you take the trouble to look at his plots, you will see that the straight-line segmenmts are numerous, parallel, and obvious. It is quite convincing. It is their slope which gives the sensitivity to dH/dt."
    This closely parallels a suggestion by Spenser:
    "Note the linear striations in the data that are approximately parallel to the feedback specified in the model simulation indicated by the dashed line. This potentially explains the linear striations seen in Figure 3a as a reflection of the net feedback operating in the climate system on intraseasonal time scales."
    Given this, do you agree that the slope of "linear striations" in the graph above (approximately parallel to the red line) also "give the sensitivity"?
  40. Tom 39, that is a curious plot. If it refers to a system like the ones we have been discussion, I can't imagine what process creates the bowing out of the nearly vertical lines. Assuming that the horizontal axis represents temperature and the vertical axis represents rate of heating, it is clear the temperature is being affected by something else and heating has almost no effect. Doug 38 You refer to Spencer's hypothesis. To my way of thinking, he has put forward no hypothesis. Feedback is the question of the century. Previously one could not measure feedback without including solar forcing. Spencer has discovered how to separate feedback from forcing in satellite data and has used it to measure the sensitivity of feedback to solar heating. He did it by utilizing periods of time when clouds were heated more by some non-radiative forcing, such as ocean currents, than by the sun. That eliminated the sun from the forcing leaving only the feedback radiation. What hypothesis do you refer to?
  41. 40, Uncle Ben,
    Spencer has discovered how to separate feedback from forcing in satellite data...
    No, he hasn't. Repeating it as often as you can does not make it so.
    He did it by...
    No, he didn't. He didn't succeed. His logic was grossly flawed, and your tacit and uncritical acceptance (acceptance? praise and worship is more like it) is singularly unconvincing. Your arguments to date amount to nothing more than "Spencer is great" and "I like what he said."
  42. Uncle Ben @ 40, you ask:
    What hypothesis do you refer to?
    Earlier in your comment, you claimed:
    Spencer has discovered how to separate feedback from forcing in satellite data and has used it to measure the sensitivity of feedback to solar heating.
    Until Spencer's 'discovery' has been reviewed and validated, I regard it as only an hypothesis. Clearly, from comments here and elsewhere, there is a weight of scientific analysis suggesting that Spencer is wrong. In other words, Spencer's science is not yet independently supported. When there is a weight of scientific analysis that supports his claim, I will elevate it from hypothesis to theory. Does that sound fair?
  43. Uncle Ben @40, let me assure you that the x-axis represents temperature anomalies in degrees K, the y-axis represents TOA net radiative flux anomalies in W/m^2, just as in the previous figure shown by me, and as in the figure shown by muoncounter @26. Further, just as in the previous figure I showed you, radiative flux is the only source of heating (something which is not true in the figure muoncounter showed). Therefore based on the reasoning you stated in 5, and which is the foundation of your case, the slope of the lines which approximately parallel the red line must "give the sensitivity". If they do not, then you must provide a reason for the exception or admit the counterexample refutes your theory.
  44. 35 - Ben "I am willing to try to answer your questions regarding Taminos post" I don't recall asking you any questions regarding that post other than how could you say that tamino denies dH/dt vs dT represents inverse sensitivity when he says explicitly that. You did not respond to my correction (which, itself could be wrong, and if so you could say why). I'm doubtful...
  45. Les, (44), my reply was that the post I referred to was not signed, and I relied on commenters to say who wrote it. It may have been someone else. You may be right.
  46. Uncle Ben#40: "He did it by utilizing periods of time when clouds were heated more by some non-radiative forcing, such as ocean currents, than by the sun." That's quite a trick! If the figures posted above are representative of this great work, where are the gaps between monthly observations that represent months when the sun was doing the heating? As far as 'heating clouds by some non-radiative forcing,' that mechanism needs a bit more substantiation. FYI: tamino's analysis was linked here.
  47. Uncle Ben - You have now been pointed to multiple issues with Spencers work. These criticisms include some peer-reviewed papers: Dessler 2011 - "It is also shown that observations of the lagged response of top-of-atmosphere (TOA) energy fluxes to surface temperature variations are not evidence that clouds are causing climate change." Trenberth et al 2011 - "...some efforts have been shown to contain major errors and are demonstrably incorrect. variability is not a deterministic response to surface temperatures...many of the problems in LC09 have been perpetuated..." They also include Taminos analysis, comments here, and the noteworthy problems in many of Spencers works with basic statistics. If you continue to hold to Spencers work without considering or addressing these issues, I would have to suspect you are suffering from confirmation bias.
  48. 45 - Ben. Ummm, ahhh... eh? Anyway. I had thought, with your history in statistics etc. maybe some detailed discussion... I'll leave it at that.
  49. muon counter 46 KR @ 47 Many thanks for the link to the part of Tamino's treatise that you find most relevant. The beginning is quite clear, something that Spencer might have written. He supports the importance of speed of the process being discussed, including the fact that warming of air by ocean surface is fast and warming of ocean by the sun is slow. Where he diverges from Spencer is his undertaking to compute the sensitivity of the composite process from the jagged line. He says that to take the slope of just the jags is an error if you want to measure the sensitivity of the entire system to radiative forcing. My understanding is that Spencer is looking for the sensitivity of temperature to the feedback from CO2, which is what Hansen and others blame for the total strength of global warming. Since the effect of feedback from CO2 warming does not involve the slow process of ocean waming, it is quick, as acknowledged by Tamino. That is why the use of the slope of the jags is not a mistake but is added information. In Spencer's plots, showing short-term effects, the curvy parts show the ocean surface not in equilbrium. That is why one does not attempt to fit them with straight lines. The critics are right that to include everything in these short-term plots would be a mistake. But the parts of the plots that Spencer uses are straight, which indicates that the cause of the change happens quickly, reaching equilibrium in weeks, not years. So I think Tamino is correct up to the point where he objects to the use of the jags.
  50. There are three commonly used definitions of climate sensitivity. The slowest is the Earth System Sensitivity. The Earth System Climate Sensitivity is the change in temperature for a given forcing once equilibrium has been reached for all feedbacks including slow feedbacks. As slow feedbacks include the melting of ice sheets (with a time scale of thousands of years) and the equilibriation of atmospheric and deep ocean CO2 concentrations (time scale in the hundreds of years), ESCS measures sensitivity in the long term. More commonly used is the Charney Climate Sensitivity, which is the temperature reached for a given forcing after equilibrium is reached including all fast feedbacks, but no slow feedbacks. "Fast feedbacks" include such things as the watervapour feedback (time scale to equilibrium of days), changes to the cryosphere excluding ice sheets ie, snow and sea ice (time scale to equilibrium - decades) among a host of others. The short term climate sensitivity is the Transient Climate Responce, which is defined as:
    "The transient climate response is the change in the global surface temperature, averaged over a 20-year period, centred at the time of atmospheric carbon dioxide doubling, that is, at year 70 in a 1% yr–1 compound carbon dioxide increase experiment with a global coupled climate model. It is a measure of the strength and rapidity of the surface temperature response to greenhouse gas forcing."
    (My emphasis) So even the most rapid of the commonly defined measures of climate sensitivity is a response over decades. But by fiat, Uncle Ben declares that "... effect of feedback from CO2 warming does not involve the slow process of ocean waming ...". From that he concludes that measuring the sensitivity to only those processes which reach equilibrium in a matter of days measures the Charney Climate Sensitivity which is known to take decades, indeed up to a century or more, to reach equilibrium. It is amazing what absurdities you can believe when you allow yourself to use false premises asserted by fiat anytime they are needed.

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