Congratulations (finally) to Spencer and Braswell on getting their new paper published

Congratulations, Dr. Spencer, on getting this important paper published. I salute you for your persistence in the face of hostile reviews. Thanks for your synopsis. Its a shame science articles tend not to be written in clear English – in this case I suspect subtlety in the face of hostile politics, as much as professional jargon, necessitates this.

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.

Dr. Spencer, in reading your book, I was struck by your use of a simple model to demonstrate the top-level, emergent behavior of a complex system. This has similarities to a study I’ve been working on.
The GCM climate models, and many other modeling regimes, try to model all the minutia of a complex system, trying to get each sub-system just right, getting the interactions between all the subsystems right, getting all the initial conditions and forcing functions right, etc. The unspoken assumption is that if one can just get all the subsystems right, the model will mimic the emergent behavior of the real system. The problem is that in practical terms, you can never get all the processes, all the initial conditions, or all the interactions exactly right, and the model fails in unexpected ways. There always seems to be just this one little detail to fix, and it will be right. And, of course, each little detail is harder and more expensive to fix, and needs another order of magnitude of compute power to do it right. The cycle never ends, and in the end, you have a hugely complex, insanely compute-intensive program that will be right if you can just get the funding to fix this one last detail. And it really doesn’t perform any better than the simple simulation you started with. Through the process, you tend to learn a lot about modeling, but not so much about the process you were actually trying to study.
I certainly hope this work gets the attention it deserves.

Hugely, Pamela? I love the word “hugely”.

Congratulations to Roy Spencer and William D. Braswell!
This question occurs to me: where are the works validating positive feedback?

Dear Doctors,
As others have said: Congratulations!
I must spend some time digesting that paper.
Aside from that, you mention models, and as many of the rest of us have come to understand, models aren’t worth much save to understand a brief glimpse of ‘what’s happening now.’
It is for that reason that most –if not all– climate models are essentially worthless and broken beyond repair: You can’t know the future, so you can’t predict it with any degree of accuracy, unless you’ve manipulated the past –and the present– sufficient to know the likely outcome …
It is my considered opinion that what most modelers don’t comprehend –or refuse to internalize– is that because of the changing nature of the beast they attempt to model, they can never begin to produce anything considered remotely accurate 100% of the time.
Tomorrow isn’t yesterday. Tomorrow, something big in the cosmic nature of things might happen and upturn the apple cart. What then?
And, as we both know: NOTHING remains static for very long. The modelers KNOW such, and are playing the unknowing like a cheap banjo. They contend that the Earth’s climate system is supposed to remain static, and that humans are upsetting that condition.
Perhaps if we were to know the future with a fair degree of certainty –a thing I doubt will ever happen– then we’d be able to surmise a modicum of prescience, and forecast future weather events. But that’s entirely wishful thinking.
It is because of the variability of the beast and its thoroughly unpredictable behavior, that attempts at modeling are essentially academic endeavors only.
I wonder: Are those ‘cheap banjoes’ starting to pay attention?
Once again: Congratulations on being published!

“Interestingly, in order to convince the reviewers of what I was claiming”
Dr. Spencer, what you guys had to do was prove to them that they were wrong,
and that took years….
Thank you!

Loved the book, Dr Spencer, and I am sure I shall find the article fascinating, although much may go over my head.
I would also be very interested to see the history of the single hostile reviewer, should you feel able to release this information (and I fully understand if you are either unable or unwilling).
I also agree with Amino Acids: “This question occurs to me: where are the works validating positive feedback?”

Hello, Roy.
I see that you are concentrating specifically on non radiative forcing that is internal to the climate system.
However radiative forcing from above and which is external to the system (solar) must always ‘prime’ the system in which those non radiative forcings then arise.
I have been trying to create a complete climate description that integrates variability from above (solar) with variability from below (oceanic) and I don’t think we can accommodate all climate observations without invoking both.
Leif Svalgaard takes the view that all climate changes are internally generated from ‘bottom up’ but many including myself see scope for a longer term slow cycling from solar variability above on a ‘top down’ basis.
Does your work provide any guidance as to how variations in external radiative forcings might affect those non radiative internal forcings ?
I see the oceans as being the location where the former is converted to the latter over time and the air circulation systems (latitudinal positioning) with the hydrological cycle (variations in speed or intensity and including cloudiness and albedo) always operating to neutralise any divergence between the external radiative (from above) and internal non radiative (from below) processes so as to provide a strongly negative response to either type of forcing in either direction (warming or cooling).
In particular, if solar variability were to have differential warming or cooling effects on the separate layers of the atmosphere then solar variability could alter the temperature of the stratosphere by changing the upward energy flux and thus affect the pressure distribution (and so change cloudiness and albedo) below the tropopause. That would be an example of a radiative external forcing becoming disguised as an internal and negative non radiative forcing.
Would that wider overview fit with your findings concerning internal non radiative processes ?

Congratulations, Drs. Spencer and Braswell! Your persistence has finally paid off.
Now put on your helmets and take to the trenches. Incoming!

Dr Spencer:
What does Lindzen say about this paper?

Another excellent paper from Dr. Spencer, added it to the ever growing list,
800 Peer-Reviewed Papers Supporting Skepticism of “Man-Made” Global Warming (AGW) Alarm

Interesting that LGF posted Dr. Spencer’s paper with the encouraging comment,
“You know you want to understand what he thinks, even if it is to prove him WRONG!”
Tagged: Denialist
I take it Journal of Geophysical Research is the new home of the “denialists”.
It is good to see Charles Johnson has an open mind and is willing to honestly discuss things that may not adhere to his ideology, not.

I read Dr. Spencer’s book back in April and wondered when this seminal work on feedback would be published. I am glad Dr. Spencer was persistent in accommodating the hostile reviewer so that it it finally appears in the peer reviewed literature.
Congratulations, Dr. Spencer. I am now looking forward to your next paper.
I now wonder if any of the computer models will be adjusted to fit these new results.

I have read once people over at Real Climate claiming that Spencer always advertises his work in a way that inflates the level to which what has been said in his papers challenges the majority position in climate science. I thought that was just their jealousy and a part of the smear campaign against the skeptical scientist whose research is dangerous to their agenda.
However, this new paper seems to indirectly confirm their allegations. This new paper was extensively promoted by dr Spencer for months as a breakthrough that would finally prove that the climate feedbacks are dominantly negative and that the climate scientists were fooled by Mother nature into believing in the positive feedbacks. From the abstract above we can see nothing of the sort. The conclusion is that a “more accurate measurement is needed”.
The basic idea that the diagnosis of the feedbacks was biased by not taking into account the natural cloud variability, an “internal radiative forcing” of the climate system is well known from the previous Spencer and Braswell paper from 2008. What is new here? We know nothing about the real feedbacks, just as we did not know before. What exactly changed in the state of knowledge of the climate science about the feedbacks with this paper?

Dr. Spencer, your data given is more than welcomed. On first scan of your paper, without delving into the fine details yet, when just viewing your Figure 1 and Figure 3 data, it appears the by the satellites our climate system is very close to a totally randomized system. Figure 3 does show a very small warm tendency over this period but it is mostly counteracted by rather large random cooling excursions irregardless of the current forcing, plus or minus. Very interesting. Hope I’m interpreting that right. I’ll read on.

Here is an intense and well-written editorial which succinctly puts it all into perspective.
And yes, Dr. Spencer is mentioned.
An Al Gore is mentioned a few times, too. LOL
Read it. It is worth it.
http://www.washingtontimes.com/news/2010/aug/24/al-gores-global-warming-crusade-shrinks/?page=1
Chris
Norfolk, VA, USA

Congrats!! All the hard work is finally getting where it belongs.

Ivan… You question what is new in this paper and what advancement of the knowledge base does it possess.
Well it shows that the AGW Hypothesis is flawed… I would have thought, that alone would be enough?
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. After all, it is they who are hypothesising an effect on the natural system. Surely they can show it without flaws…. and surely it is upon them to understand the natural system before attributing anthropogenic changes to it.

Maybe I’m missing something but it seems to me that the data in Figure 1 (of the paper) tells a pretty simple story. Firstly LW+SW depends only weakly on T. With r^2 around 0.2 the regression on T explains only about 20% of the variability in LW+SW; so 80% depends on something else. To the extent that this dependence is real the data show an increase in LW+SW for an increase in T, as expected without any feedback, or with some negative feedback. But I think this is inconsistent with a dominant positive (with respect to T) feedback, which should show a decrease in LW+SW (heat being trapped more) with increasing T. What am I missing?

Reading this, I cannot shake the images from Bladerunner, of the always wet, humid conditions in L.A.

Excellent article. I will have to read it a few more times to digest it.
I do think that this is where our effort should be concentrated. Rather than squabble with AGW proponents about sea ice thicknesses and Siberian temperature records I think that we need to expose the models for the weak and flimsy approximations that they are.
It really has to be stressed that these models are no more than guesses and any claims to long term accuracy are blatant lies.
THIS is where the battle needs to take place.

DocMartyn says:
August 28, 2010 at 6:44 pm
“The models are infinitely adjustable, and modelers stop adjusting when they get model behavior that reinforces their pre-conceived notions.”
Which means they are not models, they are fits.
My aunt Agatha used to have fits. And yes, she too would stop when she got what she wanted.

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 email which was a comment on your explanation of getting heat from warm to cool.

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.

“G&T dogma”
What’s G&T?

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@#$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.

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.

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.

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.

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.

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.

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.

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”.

jorgekafkazar says:
August 29, 2010 at 3:09 pm
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.
Ramanathan
It is remarkable that general circulation climate models (GCMs) are able to explain the observed temperature variations during the last century solely through variations in greenhouse gases, volcanoes and solar constant. This implies that the cloud contribution to the planetary albedo due to feedbacks with natural and forced climate changes has not changed during the last 100 years by more than ±0.3%; i.e, the cloud forcing has remained constant within ±1 Wm–2. If indeed, the global cloud properties and their influence on the albedo are this stable (as asserted by GCMs), scientists need to validate this prediction and develop a theory to account for the stability

jeef says:
August 29, 2010 at 1:36 pm
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.
————
That answer is a little bit weak. Any author tends to overestimate the
explanatory power of his article. One function of a peer-reviewer
is to bring the author down to earth: ‘your results/observations are
not sufficient to support that particular conclusion’.
So there is no way of knowing whether (a) this normal moderation or
(b) hostility to sceptics, was the reason for the lengthy review process
in this case.
What can be said is that. had S&B been able to unequivocally show
that positive feedbacks are not important they would have broken
through any review-barrier, hostile or not. They could not do so
and the question remains: what’s so revolutionary about this work?

mikael pihlström says: “what’s so revolutionary about this work?”
You must be joking, right? This is really important, as we have actual measurements to show that the global warming due to CO2 is moderated by negative feedbacks, not positive feedbacks as postulated by the CAGW scientists.
It is evident to me that the sum of immediate negative feedbacks is a long term moderation of warming. Thus the CO2 induced sensitivity is not significant, just as the ice records show. and as current flatlined temperatures show.
This is HUGE!!

Well the late Carl Sagan, went to his grave; having spent a good part of his life looking for intelligent life in the universe; and never discovered so much as a single binary digit of observational scientific evidence, for the existence of such life, or for that matter, ANY life, outside a shell of about +/- 20 km about mean sea level on planet earth. Some aren’t so sure there is any intelligent life even within that shell.
So who wants to be the “climate scientist” who is destined to go to his(er) grave having searched for a cloud that made the surface in its shadow zone warmer, when it passed between the sun and the surface ?
Remember that “weather is not climate” thing; and if the mean global cloud cover on planet earth, increases for periods of climatic significance (how about 30 years), the mean temperature of the earth WILL go down; NOT up.
Clouds are always a negative feedback effect.
But the playing field is wide open for any “climate scientist” who wants to do a Carl Sagan type exit some day.
And people actually have to write scientific papers for journals to show this ?

“”” 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”. “””
Dave; I don’t know who you are quoting in the above 1) citation but I certainly agree with their conclusion; BUT, if that is the extent of their cloud comment; then they don’t even understand the problem.
The earth albedo contribution due to cloud tops, is just one aspect of clouds. Some clouds actually precipitate H2O molecules in various physical manifestations; such as rain, snow, sleet, whatever; and clouds that do that also tend to absorb large amounts of solar radiation and block it from reaching the surface. This effect can be even greater than the albedo effect.
So talking about “difficulties” in monitoring cloud albedo, is to totally avoid the issue that we don’t have any network that is ground based so it can monitor the total cloud attenuation effect on incoming solar radiation.
That can only be done from the surface by optical measurements of the resultant ground level total (solar) spectral irradiance on the surface.
Even the surface stations that measure surface or near surface Temperatures to input into GISSTemp and the like throw away valuable cloud information by simply reporting a daily min/max average for the temperature, instead of an actual integrated time/Temperature “area” that in some way can give a clue to the total cloud effect.
It’s hard to take any interest in the reported data, (on tempertaure anomalies) when it is clear from the methodology that the purveyors don’t even understand the problem.

Tim Klark: “They convinced the reviewers of JGR (is that publication prestigious enough?) that cloud cover is a forcing. ”
They convinced the reviewers of their previous paper the same thing, two years ago. My question is what is new here?
“Feedback is irrelevant, and the IPCC reliance on an assumed positive feedback to support global catastrophe is erroneous.”
As far as I understood Spencer the feedbacks are the single most important issue in climate science!
Further, it well may be true that assuming the large positive feedback is erroneous, but that does not follow from the Spencer’s results. That’s the problem. He himself says that we don’t know and have no way of knowing the long-term climate feedback, which is the only important feedback in the context of climate change. So, as I said, the real climate sensitivity which critically depends upon the long term feedback could have been even larger than the wildest IPCC projections, and that still will be quite consistent with the Spencer falibilistic position.

Tim Clark says:
August 30, 2010 at 12:01 pm
READ
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.)
————-
You seem to be quoting the post text for the home audience (WUWT)
all the time. The article is much less confident:
60. Striations in 9 years of global average CERES radiative
fluxes from the Terra satellite have a slope around 6 W
m−2 K−1 in net (LW + SW) radiative flux variability. This is
similar to the feedbacks diagnosed by Lindzen and Choi
[2009] from interannual variability in recently recalibrated
Earth Radiation Budget Satellite data, as well as that diagnosed
for a composite of 15 strong tropical intraseasonal
oscillations analyzed by Spencer et al. [2007]. Although these
feedback parameter estimates are all similar in magnitude,
even if they do represent feedback operating on intraseasonal
to interannual time scales, it is not obvious how they relate to
long‐term climate sensitivity.”
In the following numbered paragraphs (61-63) S&B nearly bend
over in introducing caveats and admissions of uncertainty concerning
the whole enterprise. Not exactly a knock-out of AGW.

Mr Smith- You are right. Clouds don’t heat. But they needn’t heat to be a feedback. All they need to do is to slow the rate of cooling. That is their tendency at night.
“Who says so?” – Any basic weather text book will tell you that.
Although you are also right “last night’s weather is not climate”, night happens about half the time and the aggregate effect is very important to climate. Furthermore night makes up half of “always”.
I have reviewed Wentz et al (2007)
What I find is a study that indicates that globally The hydrologic cycle appears to increase at a greater rate than climate models have predicted. I don’t see any part that refers to “precitable” clouds nor additional radiation absorbed by them.
I did notice these comments however:
“…both climate models and observations indicate that the total water vapor in the atmosphere increases by about 7% K^-1.
More than 99% of the total moisture in the atmosphere is in the form of water vapor….”
You are aware the water vapor is a very significant GHG are you not Mr Smith?
Since most clouds do not rain I would say it is quite a jump to say “RAIN=CLOUDS”.
The last paragraph of the paper concludes:
“…Will warming really bring a decrease in global winds? [needed to account for the apparent decrease in the apparent discrepancy in precipitation found] The observations reported here suggest otherwise, but clearly these questions are far from being settled. “
Your citation does not in any way contradict my statement that clouds do not have a negative feedback effect at night.
HTH – yolo

Sorry I wasn’t clear. My first post here was sent in error. Please delete it. My second post expressed my thoughts clearly.
REPLY: I have no idea which is first second third or whatever. Pick one, resubmit and say ignore previous and we’ll take it out -Anthony

“”” Yuba Yollabolly says:
August 30, 2010 at 7:59 pm
Mr Smith- You are right. Clouds don’t heat. But they needn’t heat to be a feedback. All they need to do is to slow the rate of cooling. That is their tendency at night.
“Who says so?” – Any basic weather text book will tell you that.
Although you are also right “last night’s weather is not climate”, night happens about half the time and the aggregate effect is very important to climate. Furthermore night makes up half of “always”.
I have reviewed Wentz et al (2007)
What I find is a study that indicates that globally The hydrologic cycle appears to increase at a greater rate than climate models have predicted. I don’t see any part that refers to “precitable” clouds nor additional radiation absorbed by them.
I did notice these comments however:
“…both climate models and observations indicate that the total water vapor in the atmosphere increases by about 7% K^-1. “””
Well Yuba, I don’t think you reviewed Wentz, et al very carefully.
As you reported: “”” “…both climate models and observations indicate that the total water vapor in the atmosphere increases by about 7% K^-1. “””
But it is what you missed. Wentz et al also reported that Total Global Evaporation, and Total Global Precipitation ALSO increased by that same 7% per deg C increase in mean global surface Temperature. The GCMs on the other hand disagreed, saying those two only increase by from 1-3%. In other words the GCMs are in error by as much as a factor of 7 times from what Wentz et al OBSERVED to happen.
Now it is obvious that Total Global Evaporation and Total Global Precipitation must balance over time; or else we would end up with the oceans over our heads.
But the important point is that Total Global Precipitation goes up by 7% for a 1 deg C rise in Temperature.
I put it to you Yuba; A 7% increase in Total Global Precipitation might reasonably be expected to be accompanied by about a 7% increase in (precipitable) cloud cover. That increase could comprise an increase in cloud area, or an increase in cloud water content and Optical Density, or an increase in persistence time of the cloud; or some combination of all three. Yes you are correct that Wentz et all DID NOT mention any increase in precipitable clouds; I did that as an obvious corollary to their paper. So the discussion is quite open to anyone who accepts the truth of what Wentz et al reported in that paper to refute my corollary that must follow as a consequence of their results. If you have been reading WUWT diligently, you will probably have counted that it is about 20 times since July 7 2007 that I have pointed out this obvious consequence of the Wentz paper. (here at WUWT). They did not say it; I did !
It is not reasonable to postulate a 7% incerease in Total Global Precipitation; with no increase in clouds that are capable of precipitating that increased rain/snow/sleet/hail/whatever.
As for your observation that night time lasts about 50% of the time; daylight is well known to last for more than 50% of the time in total because of atmospheric refraction, that conveys sunlight to the surface even after the sun is geometrically below the horizon. But not to be nit picky; lets say half time daylight and half time night. The earth surface on average radiates 390 W/m^2 according to Trenberth. That number consists of a much lower value being emitted at night from the colder dark areas of earth for half the time; plus the much higher daytime rates of emission due to the sunlight hitting the surface, at a maximum rate of about 1000 W/m^2; so in fact the greatest cooling rate of the earth happens in the hoittest deserts during the highest temperature periods of daylight (T^4 effect)
Now throw in some Optics. The Sun is a near point source (1/2 degree divergence); so a cloud blocks the whole solar beam by whatever average optical transmission coefficient the cloud has depending on its water density; so it forms a quite distinct shadow zone; with a small 1/2 degree penumbral edge.
However the outgoing LWIR radiation is highly diffused; at least Lambertian (cos(theta)) for a smooth surface (water) and likely near isotropic for a rough surface. So the very same cloud that blocks some fraction of the total solar beam; only intercepts a small fraction of the diffuse LWIR; most of which misses the cloud; and the higher the cloud; the more radiation misses it.
So the cloud is very inefficient in intercepting the outgoing LWIR radiation; compared to its blocking of the incoming solar beam.
And lastly; those high clouds at night are not the cause of the warmer wetter surface; they are the result of it.
If the clouds were a feedback effect at night, the surface irradiance contributed by the cloud must diminish as the Fourth Power of the cloud height. I shouldn’t have to explain that but for sure somebody won’t get it.
The driving source of “heat” is the thermal radiation from the daytime heated surface. The irradiance of a cloud bottom from some radiating surface element that is illuminating the cloud at some inclined angle (theta) falls off as the square of the cloud height; and it also drops as Cos^4 (theta) for a Lambertian emitting source. (I (theta) = I (zero) Cos (theta) ) .
So the cloud irradiance from some surface elements goes as (1/H^2).Cos ^4 (theta). For an isotropic radiating surface the angular fallof is only Cos^3 (theta), but the value of I (zero) is much lower to start with.
So now the cloud may reflect some of the LWIR falling on it from our surface element; with whatever spectral reflectance it has; and it will also absorb some of the LWIR radiation; and eventually re-emit soem thermal radiation spectrum, about half of which will go up towards space, and half return to the ground.
The amount returning to our original source region will also suffer a (1/H^2) .Cos^4 (theta) attenuation. so the round trip loss is (1/H^4). Cos^8 (theta) .
Needless to say; not much of the surface emitted LWIR makes it back to where it started out. Sure some of it goes to some other spot; but that (1/H^4) is a killer, but the Cos^8 (theta) really rubs slat in the wound.
And according to all of those textbooks you mentioned; the higher the clouds are at night, the greater is the amount of “warming” they cause.
Well of course they don’t cause any warming at all. But as a result of the surface being warmer (at night) the higher the moist air has to rise before it reaches the dew point and forms those high clouds; which are the supposed reason the surface is warmer.
And if it is both warmer and less humid; then the dew point is even at a higher altitude. Yes those high clouds really play havoc with the (1/H^4) attenuation, and the Cos^8 (theta) obliquity factor.
So I suggest reading some different books, than the ones that say clouds are a positive feedback.
I loved these little gems:-
“”” You are aware the water vapor is a very significant GHG are you not Mr Smith?
Since most clouds do not rain I would say it is quite a jump to say “RAIN=CLOUDS”. “””
Well blow me down; I could swear that all the climate gurus say H2O is not a GHG but is a feedback factor that enhances CO2 warming. Now you are trying to tell me that H2O is a GHG. So why doesn’t the EPA regulate that as a dangerous pollutant too. Specially since our cars emit more H2O than they do CO2; and there is nowhere in the troposphere where CO2 ever exceeds H2O; maybe at Vostok in the dead of winter midnight that could be possible; that’s when the surface emitted LWIR emittance is more than a factor of six times lower than it is for the global mean surface temperature; so not much LWIR radiation to intercept.
But back to the GHG thing.
I do agree with you on this; H2O IS a GHG, and not the “weak” one that the late Stephen Schneider claimed it is (compared to CO2).
But then H2O also has this other property. It also intercepts a significant fraction of the incoming solar spectrum energy starting at about 750 nm wavelength and then in multiple bands out to the 4 micron range beyond which only 1% of the solar energy resides. But the 750 ->>> portion is about 45% of the total solar spectrum, and when you look at the water bands, it is easy to see where H2O could easily absorb as much as 20% of the solar energy. That’s the main reason why the air mass one ground level insolation is only 1000 W/m^2 instead of 1366 W/m^2
So not only does H2O as a vapor have atmospheric warming potential as a result of absorbing LWIR surface emitted thermal radiation; but it can cause additional atmospheric warming due to the absorption of that incoming 750 nm -4.0 micron solar energy. And of course what solar radiation is absorbed by H2O in the air, does not reach the ground; so it cools the ground.
Now true; to the extent that that captured solar energy warms the air and increases the thermal radiation from the atmosphere; that radiation is emitted isotropically; so only a half of it is directed towards the earth to ultimately warm the surface; the other half escapes to space. Well maybe more than half escapes; because the higher less dense cooler atmospheric layers (and H2) molecules) result in narrower absorption bands; compared to those of the lower denser hotter layers; so the upwards escape route is favored over the downward surface destination route.
And lets not forget that without the water vapor; what reaches the surface (say ocean) is “short” wave solar spectrum radiation; which propagates deeply into the ocean maybe several hundred metres, and warms it; but the surface directed downward LWIR radiation that the atmosphere substitutes for that solar energy (half of it) is absorbed in the top 10 microns of the ocean surface (mostly) and that results in prompt evaporation of even more of that GHG water vapor H2O.
But this last one is a doozy:- “”” Since most clouds do not rain I would say it is quite a jump to say “RAIN=CLOUDS”. “””
Read it again; I said “RAIN = CLOUDS” I DID NOT say RAIN = CLOUDS. So I agree with you; most clouds do not rain; which the cognoscenti might interpret as the precise reason why I actually used the term “PRECIPITABLE CLOUDS”; meaning that portion of the global cloud cover which is capable of resulting in precipitation.
Now I am quite happy to entertain any research results you care to report of any significant amounts of Precipitation of the rain/snow/sleet/hail/whatever, variety that you have observed in the total absence of clouds.
And I will repeat my assertion; warm humid nights following even warmer humid days may result in high clouds forming; the reverse does not happen (high clouds causing warm humid surface temperatures).
H2O; Water, is the only GHG that is a permanent component of the earth’s atmospehre in ALL THREE of its phases of ordinary matter, gas/liquid/solid.
As a vapor it has atmospheric warming properties as a result of both LWIR thermal radiation absorption and also direct absorption of a significan portion of the incoming solar spectrum. The former may also tend to warm the surface; but the latter cools the surface.
But in the other two phases as liquid or solid clouds, H2O acts to cool the surface. Nobody ever observed the surface Temperature to increase in the shadow zone, when a cloud passes in front of the sun; it always gets cooler.
Regardless of what CO2 or TSDI variations or any other GHG attempts to do to change the mean temperature of the earth; the stable comfortable temperature regime is maintained by feedback regulation due almost entirely to the Physical and chemical Properties of H2O. Yes I am sure there are biological effects as well; but the melting point, and boiling poiint, the phase change latent heats; the specific heats; the molecular absorption spectra, the bulk optical absorption spectra, the Clausius-Clapeyron equation, and on and on, are the things that control the earth’s average Temperature. So long as the oceans persist; we could not significantly change the temperature of this planet; either up or down; even if we wanted to.
And suppose we could; What Temperature would you set it to; and WHY !!

Mikael Pihlström:
“Had S&B been able to unequivocally show that positive feedbacks are not important they would have broken through any review-barrier, hostile or not. They could not do so and the question remains: what’s so revolutionary about this work?”
Sometimes the perfect is the enemy of the excellent. Spencer did show that the current feedbacks are negative and weaken even more the very tiny direct warming effect of doubling CO2. While he did not disprove the possibility of long term stronger feedbacks, the current negative feedback to the direct CO2 forcing does not inspire confidence that there will be long term larger warming feedbacks. Spencer does not have to disprove that long term feedback from a CO2 increase will be much greater than short term feedbacks. Anybody claiming larger long term feedbacks needs to prove his point with real data.
What is great about Spencer’s work is that it is based on actual real data from real sensors. Believe it or not, that is much more persuasive than predictions from models. BTW, of course Spencer is going to be more cautious in an academic paper than on a popular blog because the target audiences are so different.
Spencer’s finding that the measured feedback from doubling CO2 is 0.6 deg. C undermines the arguments of alarmists who have models that predict feedbacks that are up to an order of magnitude larger.
WRT the political debate about cap and trade in the USA, the timing of this paper is perfect.