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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. A subsequent study by Dessler (2011) found that Spencer's paper was not a test of climate sensitivity or feedbacks, and his assumptions do not match empirical observational data.

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.

Debunked by Trenberth, Fasullo, and Abraham

A commentary published in the same journal (Remote Sensing) by Trenberth, Fasullo, and Abraham found that Spencer's simple model does not have a realistic representation of many key aspects of the Earth's climate system.

"Because the exchange of heat between the ocean and atmosphere is a key part of the ENSO cycle, SB11’s simple model, which has no realistic ocean, no El Niño, and no hydrological cycle, and an inappropriate observational baseline, is unsuitable. Use of a reasonable heat capacity for the ocean is also crucial. Importantly, SB11 treated non-radiative energy exchange between the ocean and atmosphere as a series of random numbers, which neglects the non-random variations of this energy flow associated with the ENSO cycle...None of those processes are included in the SB11 model and its relevance to nature is thus highly suspect."

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.

Trenberth et al. found some other key problems in the paper.  It doesn't provide enough information for other scientists to repeat the study.  However, when trying to replicate their results, Trenberth et al. found that the climate models which matched the observed data best were those with a climate more sensitive to greenhouse gases, which directly contradicts Spencer and Braswell's claims that the climate is not sensitive to greenhouse gases.  However, the correlation between model sensitivity and regression strength is of marginal statistical significance.  Thus they conclude that Spencer and Braswell  fundamentally took the wrong approach:

"Consequently, bounding the response of models by selection of those with large and small sensitivities is inappropriate for these model-observation comparisons."

Trenberth et al. conclude that Spencer and Braswell are not testing climate sensitivity at all, but rather how well climate models simulate El Niño.

It's also worth noting that Remote Sensing 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 et al. 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

Editor-in-Chief Resigns

Wolfgang Wagner, editor-in-chief of the journal which published Spencer's study, has stepped down from his position at Remote Sensing. Wagner concluded the Spencer's paper was "fundamentally flawed and therefore wrongly accepted by the journal". More here...

Debunked by Dessler (2011)

In their paper, Spencer and Braswell analyzed 14 models, but they only plotted the 3 with highest and 3 with lowest equilibrium climate sensitivities.  A paper by Dessler (2011) found that in the process, Spencer and Braswell excluded three of the climate model runs which best matched the observational data (Figure 1). 

dessler 2011

Figure 1: Dessler (2011) reconstruction of Spencer & Braswell's Figure 3, showing relationship between top-of-atmosphere (TOA) net flux and surface temperature, as a function of lag between them.  The blue line is the observational data chosen by Spencer and Braswell.  The red lines show other available observational data.  The black lines show climate model results.  The black lines with crosses show the climate model runs chosen by Spencer and Braswell in their paper.

Dessler found that these three model runs excluded by Spencer which best matched the data were also among those which best simulate El Niño and La Niña, which is not surprising, given that much of the temperature change over 2000-2010 was due to the El Niño Southern Oscillation (ENSO).  Thus Dessler concludes, like Trenberth et al., that

"since most of the climate variations over this period were due to ENSO, this suggests that the ability to reproduce ENSO is what's being tested here, not anything directly related to equilibrium climate sensitivity."

Spencer's claim of low sensitivity and negative feedbacks is based on this test, which is actually a test of models' ability to reproduce ENSO.  Thus Spencer's claim of low sensitivity and negative feedbacks is not supported by the empirical observational data.

Last updated on 29 October 2016 by dana1981. View Archives

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Comments 1 to 25 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.
    Response:

    [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.
    Response:

    [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-).
    Response:

    [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.

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