WUWT provided a primer on cloud feedbacks on June 12th, 2009, followed by Willis Eschenbach’s “thermostat hypothesis” also recently published. This new paper by Spencer and Braswell is in the same theme as these.
On the diagnosis of radiative feedback in the presence of unknown radiative forcing
Roy W. Spencer and William D. Braswell
Received 12 October 2009; revised 29 March 2010; accepted 12 April 2010; published 24 August 2010.
Abstract: The impact of time‐varying radiative forcing on the diagnosis of radiative feedback from satellite observations of the Earth is explored. Phase space plots of variations in global average temperature versus radiative flux reveal linear striations and spiral patterns in both satellite measurements and in output from coupled climate models. A simple forcingfeedback model is used to demonstrate that the linear striations represent radiative feedback upon nonradiatively forced temperature variations, while the spiral patterns are the result of time‐varying radiative forcing generated internal to the climate system. Only in the idealized special case of instantaneous and then constant radiative forcing, a situation that probably never occurs either naturally or anthropogenically, can feedback be observed in the presence of unknown radiative forcing. This is true whether the unknown radiative forcing is generated internal or external to the climate system. In the general case, a mixture of both unknown radiative and nonradiative forcings can be expected, and the challenge for feedback diagnosis is to extract the signal of feedback upon nonradiatively forced temperature change in the presence of the noise generated by unknown time‐varying radiative forcing. These results underscore the need for more accurate methods of diagnosing feedback from satellite data and for quantitatively relating those feedbacks to long‐term climate sensitivity.
Citation: Spencer, R. W., and W. D. Braswell (2010), On the diagnosis of radiative feedback in the presence of unknown radiative forcing, J. Geophys. Res., 115, D16109, doi:10.1029/2009JD013371.
Our JGR Paper on Feedbacks is Published
by Roy W. Spencer, Ph. D.
After years of re-submissions and re-writes — always to accommodate a single hostile reviewer — our latest paper on feedbacks has finally been published by Journal of Geophysical Research (JGR).
Entitled “On the Diagnosis of Feedback in the Presence of Unknown Radiative Forcing“, this paper puts meat on the central claim of my most recent book: that climate researchers have mixed up cause and effect when observing cloud and temperature changes. As a result, the climate system has given the illusion of positive cloud feedback.
Positive cloud feedback amplifies global warming in all the climate models now used by the IPCC to forecast global warming. But if cloud feedback is sufficiently negative, then manmade global warming becomes a non-issue.
While the paper does not actually use the words “cause” or “effect”, this accurately describes the basic issue, and is how I talk about the issue in the book. I wrote the book because I found that non-specialists understood cause-versus-effect better than the climate experts did!
This paper supersedes our previous Journal of Climate paper, entitled “Potential Biases in Feedback Diagnosis from Observational Data: A Simple Model Demonstration“, which I now believe did not adequately demonstrate the existence of a problem in diagnosing feedbacks in the climate system.
The new article shows much more evidence to support the case: from satellite data, a simple climate model, and from the IPCC AR4 climate models themselves.
Back to the Basics
Interestingly, in order to convince the reviewers of what I was claiming, I had to go back to the very basics of forcing versus feedback to illustrate the mistakes researchers have perpetuated when trying to describe how one can supposedly measure feedbacks in observational data.
Researchers traditionally invoke the hypothetical case of an instantaneous doubling of the CO2 concentration of the atmosphere (2XCO2). That doubling then causes warming, and the warming then causes radiative feedback which acts to either reducing the warming (negative feedback) or amplify the warming (positive feedback). With this hypothetical, idealized 2XCO2 case you can compare the time histories of the resulting warming to the resulting changes in the Earth’s radiative budget, and you can indeed extract an accurate estimate of the feedback.
The trouble is that this hypothetical case has nothing to do with the real world, and can totally mislead us when trying to diagnose feedbacks in the real climate system. This is the first thing we demonstrate in the new paper. In the real world, there are always changes in cloud cover (albedo) occurring, which is a forcing. And that “internal radiative forcing” (our term) is what gives the illusion of positive feedback. In fact, feedback in response to internal radiative forcing cannot even be measured. It is drowned out by the forcing itself.
Feedback in the Real World
As we show in the new paper, the only clear signal of feedback we ever find in the global average satellite data is strongly negative, around 6 Watts per sq. meter per degree C. If this was the feedback operating on the long-term warming from increasing CO2, it would result in only 0.6 deg. C of warming from 2XCO2. (Since we have already experienced this level of warming, it raises the issue of whether some portion — maybe even a majority — of past warming is from natural, rather than anthropogenic, causes.)
Unfortunately, there is no way I have found to demonstrate that this strongly negative feedback is actually occurring on the long time scales involved in anthropogenic global warming. At this point, I think that belief in the high climate sensitivity (positive feedbacks) in the current crop of climate models is a matter of faith, not unbiased science. The models are infinitely adjustable, and modelers stop adjusting when they get model behavior that reinforces their pre-conceived notions.
They aren’t necessarily wrong — just not very thorough in terms of exploring alternative hypotheses. Or maybe they have explored those, and just don’t want to show the rest of the world the results.
Our next paper will do a direct apples-to-apples comparison between the satellite-based feedbacks and the IPCC model-diagnosed feedbacks from year-to-year climate variability. Preliminary indications are that the satellite results are outside the envelope of all the IPCC models.
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Be sure to check out Dr. Roy Spencer’s book:
Roy says: “…Researchers traditionally invoke the hypothetical case of an instantaneous doubling of the CO2 concentration of the atmosphere (2XCO2).”
This is the nub in my opinion. Of course CO2 doesn’t just double instantaneously, if it did then one might well see all sorts of strange effects, but the CO2 increase occurs very slowly permitting small adjustments in the weather machine to maintain stability. Should have thought that was pretty obvious.
What you really mean Dr. Spencer is that the measurements are difficult to sort out, incoming from all the other chaotic bits of radiation flying around. This has implications with the accuracy of the theory of GHG’s, which I dislike because of violations of the laws of thermodynamics. Seems you are coming round to thinking that GHG’s are not all they are cracked up to be. Good job too.
Perhaps you can now answer my ema
What you really mean Dr. Spencer is that the measurements are difficult to sort out, incoming from all the other chaotic bits of radiation flying around. This has implications with the accuracy of the theory of GHG’s, which I dislike because of violations of the laws of thermodynamics. Seems you are coming round to thinking that GHG’s are not all they are cracked up to be. Good job too.
Perhaps you can now answer my email which was a comment on your explanation of getting heat from warm to cool.
Ivan says:
August 28, 2010 at 8:45 pm
Suggest you read the whole paper after first removing your RC brainwashing helmet.
Is that a shudder I feel or is it just Real Climate, meeting Real Science, when the best they can do is throw paint balls at the man in the hope they will retain their ever smaller band of followers.
I sympathize with Dr Spencer who had to justify every word, phrase and process to a hostile reviewer. I do now see that as quite funny that, he was not allowed to cite cause equals effect, as that phrase seems to have been so easy with those others who claim catastrophic warming to willy nilly cite, and promote as fact.
Demonstrates the depths to which science had sunk and the easy ride of climate scary mush that routinely got the trick (whoops meant tick) from the insiders in the mates review process.
I don’t blame him for going public and challenging the science in the open light as truth will win in the end. The gatekeepers will eventually fade away!! At least I hope so.
“……belief in the high climate sensitivity (positive feedbacks) in the current crop of climate models is a matter of faith, not unbiased science……models are infinitely adjustable, and modelers stop adjusting when they get model behavior that reinforces their pre-conceived notions……”
A bit like the efforts to make observations of planetary movements fit the Ptolemaic assumption that the Earth and heavens were spherical and that all motions of heavenly bodies around the Earth must be some combination of uniform circular motions.
http://upload.wikimedia.org/wikipedia/commons/0/0e/Cassini_apparent.jpg
Wikipedia does reluctantly note that the term ‘epicycles on epicycles’ : “… might be used, for example, to describe continuing to try to adjust a theory [model] to make its predictions match the facts. …….epicycles are regarded by some as the paradigmatic example of Bad Science…”.
It has long been the basis of an introduction to the history and philosophy of science, but Connolley & friends may find the story of how the medieval establishment clung obstinately to the geocentric Heavenly-Earthly dichotomy too close for comfort.
“G&T dogma”
What’s G&T?
G&T : Gerlich & Tscheuschner
Falsification of the Atmospheric CO2 Greenhouse Effects Within The Frame Of Physics
http://icecap.us/images/uploads/Falsification_of_CO2.pdf
It’s rather bizarre that in the RC world, you have to support G&T to be sceptical about our current knowledge of feedbacks and estimates of equilibrium climate sensitivity to CO2. What a@ur momisugly#$les! Well I think G&T is an unmitigated mess, so, by the same logic, I guess that converts me into a post-modernist warmist.
Dr Spencer,
My sincere congratulations on an excellent and very well drafted paper. I believe that history will view it as a “landmark” paper.
G&T is also peer-reviewed,
Falsification Of The Atmospheric CO2 Greenhouse Effects Within The Frame Of Physics
(International Journal of Modern Physics B, Volume 23, Issue 03, pp. 275-364, January 2009)
– Gerhard Gerlich, Ralf D. Tscheuschner
Spencer & Braswell 2010:
“These results underscore the need for more accurate methods of diagnosing feedback from satellite data and for quantitatively relating those feedbacks to long‐term climate sensitivity.”
If that is the timid conclusion, preceeded by a text full with maybe’s
and non-controversy, how can one (Spenser) then jump to public
strong denialist statements overnight? There should be some
congruence between what you say on different forums.
Poptech says:
August 29, 2010 at 7:04 am
G&T is also peer-reviewed.
And roundly rebutted…
http://scienceofdoom.com/2010/04/05/on-the-miseducation-of-the-uninformed-by-gerlich-and-scheuschner-2009/
http://www.worldscinet.com/ijmpb/24/2410/S021797921005555X.html
and in the interests of balance re-rebutted…
http://www.worldscinet.com/ijmpb/24/2410/S0217979210055573.html
for what it’s worth.
Publication of every detail of the peer review process used here would eliminate lots of speculation about conclusions in the final version. Otherwise, if peer review details must remain eternally secret, the true scientific method suffers onward. Is it a fact that peer review is always considered part of a secret society ? If so, why? Obviously some readers here know the answer.
I have read Dr. Spencer’s book.
What I don’t understand (or I missed) is why the planet’s response is the opposite to the PDO than it is to ENSO.
Dr Spencer’s hypothesis as I understand it is: When the PDO goes negative (it’s misnamed “cool phase” which is actually its predominantly warm phase) the rise in SST causes more ocean evaporation that subsequently leads to increased cloud formation and atmospheric cooling.
Why do we see the opposite atmospheric temperature response when El Nino warms the SSTs?
Does it have to do with the latitude of the predominant SST warming?
Thanks – yuba
Spiral patterns are characteristic of a class of nonlinear pattern formation and turbulence associated with delayed feedback – exactly what Dr Spencer described in his paper.
A PhD thesis on nonlinear pattern formation and turbulance in relation to feedback, by Matthias Bertram, includes a chapter section on “Spiral wave turbulence: – pages 109-112, part 8.2.1:
https://docs.google.com/fileview?id=0B9p_cojT-pflY2Y2MmZmMWQtOWQ0Mi00MzJkLTkyYmQtMWQ5Y2ExOTQ3ZDdm&hl=en_GB
Here is the start of this section:
8.2.1 Spiral-wave turbulence
Before considering the effects of global delayed feedback on chemical turbulence, the properties of this spatiotemporally chaotic state are briefly discussed. Chemical turbulence in CO oxidation on Pt(110) was first observed by Jakubith et al. [46] in 1990. It is found in a wide range of temperatures for an appropriate choice of the partial pressures of gases in the chamber. A characteristic property of such turbulence is the spontaneous creation of irregular wave fronts and multiple rotating spiral waves. The spiral waves repeatedly undergo breakups, leading to the formation of new spiral fragments at different locations.
Nonlinear pattern formation and turbulence were not emphasised in the paper but they seem to be in evidence.
Clouds – as we know from the recent post about “inter cloud communication”, exhibit chaotic and non-equilibrium Lyapunov-stable pattern. Furthermore, friction and damping are key ingredients in systems going in to the nonlinear pattern regime, and clouds – showing nonlinear pattern themselves – damp the climate system to cause it to also exhibit nonlinear pattern, specifically spiral turbulence as Spencer et al. show.
Pamela Gray says:
August 28, 2010 at 5:08 pm
Finally we just might be getting back on the road we were so viciously torn from by the greenniks. Decades ago, papers about natural weather and climate events were common. And useful. Then we got on this utterly nonsensical anthropogenic road to hell. I think this paper is every bit as important as Mann-debunking papers and deserves to be top of the heap. It is model debunking. Hugely.
Agree – this marks a return to real and meaningful analysis of climate.
Worth repeating on albedo:
Dave Springer says:
July 8, 2010 at 6:43 pm
More info on earth albedo measurements:
http://bbso.njit.edu/Research/EarthShine/literature/Palle_Goode_2008_ASP.pdf
This is worth reading. It’s essentially a blunt indictment of the global circulation models that are being used to frighten the sheeple into global energy use governance.
Several key statements in it are:
1) There is no reliable way to accurately measure the earth’s albedo. The few methods being used are often in “unsatisfactory disagreement”.
2) GCMs assume that albedo is constant but the one conclusive thing found by experimental measurements is that the earth’s albedo varies a lot and it changes quickly.
3) GCM assumptions of albedo vary by as much as 7% from one model to another.
4) A variance of 7% changes the earth’s energy budget by more than all greenhouse gases combined!
Incredible. A climate forcing that can’t be accurately measured, that has an effect potentially greater than all greenhouse gases combined, and the global circulation models just throw a constant arbitrary number in there for it and then pretend like it isn’t a problem. I’m stupified. I mean I knew about the large effect that albedo can have but I wasn’t aware of the problems in measuring it with great enough accuracy to factor it into the GCMs for back-calibration.
Does anyone know the current status of this paper by Dr. Lindzen and Choi?
Richard S. Lindzen, Yong-Sang Choi, On the observational determination of climate sensitivity and its implications, (Submitted to Journal of Geophysical Research, February 2010). PDF: http://www.legnostorto.com/allegati/Lindzen_Choi_ERBE_JGR_v4.pdf
Because it also deals with the problem of climate sensitivity and utilizes satellite data, similar to Dr. Spencer’s, and was also submitted to JGR. I remember Dr. Spenser has commented on this paper before, especially its earlier drafts. Maybe it has been too sharp in conclusion and too influential in the blogosphere so that it is blocked by JGR, and Dr. Spencer’s is a little milder so that they let it through?
Tenuc says:
August 29, 2010 at 12:51 am
“What we observe to be ‘random’ is actually the result of turbulence and our climate system is driven by deterministic chaos, not random chance.”
—
That was my poor choice of words. I also do not view any of these as “random”, all driven by various real physical reasons. I have one of Dr. Spencer’s simple models running on my desktop thanks to him. Similar charts you see in the paper I can generate depending on the input parameters chosen. However, mine ARE randomly chosen and those in this paper are real data from the satellite instruments stated.
I was speaking of the graphs as you see in Figure 1, 3, 9, & 12. Look at the distribution in the four quadrants of these LW Flux Anomaly vs. Tsfc Anomaly graphs and notice which quadrants the most months fall into. If you have a high number in quad 1 & 3 then temperature to radiance flux is correlated, if most fall in quad 2 & 4 they are inverse correlated. If you see many in quad 1 & 4 this is indicative of a slight warming. That was what I was referring to. If you see no weighting in any quadrants then that is what I was speaking of as “random” and should have said equally weighted up I thought that might fly over some people reading here.
My congratulations, also, to Drs. Spencer and Braswell.
This paper is in agreement with a fundamental principle of thermodynamics: in a closed system, energy in equals energy out (absent a change in storage). Clouds on Earth do act as a reflector to solar radiant energy, thus reducing the energy input to the Earth’s surface. That effect must be understood and quantified, then eliminated on a valid basis as a cause of any measured warming, before CO2 increase in the atmosphere is considered a cause of that warming.
Or, as my country cousin (but a fairly smart guy) puts it:
http://sowellslawblog.blogspot.com/2010/02/ice-age-is-nigh.html
Nice one Doc.
To those few wondering how his paper can read tamely in the conclusion yet Dr. Spencer be more vociferous the blogosphere, might I suggest you read his comments about how long it took to get published, and why. Therein lies the answer.
“It is not up to Dr Spencer to try and explain the vagaries of Natural climate change when showing the flaws in the AGW hypothesis…. Just show that natural variation is a valid explaination for the observed measurements…It is up to the AGW proponents to show that Anthopogenic CO2 is having a profound effect on climate and to explain that in a scientific way.”
I agree completely with you on this one. However, we did not need a new study and a year of painstaking review process to demostrate the same theoretical conclusion that clearly has been drawn by their previous paper from 2008! What I objected to was the inconsistency between the previous Spencer’s advertisement of this new work as a positive demonstration of the negative long-term climate feedback, and his actual results which simply show that we don’t have a clue. The long-term climate feedback could well have been extremely positive, even more positive than the most extreme IPCC projections assume, and still be be quite consistent with this new paper of Spencer and Braswell.
Ivan says:
“The long-term climate feedback could well have been extremely positive, even more positive than the most extreme IPCC projections assume…”
When will real world measurements begin to show that? It’s their hypothesis that the planet itself is debunking: what is being observed today has happened repeatedly in the past.
I have a much more realistic concern about why the current interglacial has lasted so much longer than past interglacials, and is so much cooler. We appear to be overdue for a painful temperature reversion to the mean.
Dave Springer says:
August 29, 2010 at 11:13 am
2) GCMs assume that albedo is constant but the one conclusive thing found by experimental measurements is that the earth’s albedo varies a lot and it changes quickly.
This doesn’t seem to ring true, nor could I find that statement in the reference. Surely GCM’s (at least some of them) would account for seasonal ice/snow cover affecting solar heat input. Please explain or qualify your statement or cite a better reference.
Ivan says:
August 29, 2010 at 1:52 pm
‘The long-term climate feedback could well have been extremely positive, even more positive than the most extreme IPCC projections assume, and still be be quite consistent with this new paper of Spencer and Braswell.’
Sure. Please explain the cooling trend since the Roman Warm Period to present. Or, maybe that isn’t enough time for a “trend”.