Guest Post by Willis Eschenbach
This is an extension of the ideas I laid out as the Thunderstorm Thermostat Hypothesis on WUWT. For those who have not read it, I’ll wait here while you go there and read it … (dum de dum de dum) … (makes himself a cup of coffee) … OK, welcome back. Onwards.
The hypothesis in that paper is that clouds and thunderstorms, particularly in the tropics, control the earth’s temperature. In that paper, I showed that a falsifiable prediction of greater increase in clouds in the Eastern Pacific was supported by the satellite data. I got to thinking a couple of days ago about what other kinds of falsifiable predictions would flow from that hypothesis. I realized that one thing that should be true if my hypothesis were correct is that the climate sensitivity should be very low in the tropics.
I also figured out how I could calculate that sensitivity, by using the change in incoming solar energy (insolation) between summer and winter. The daily average top of atmosphere (TOA) insolation is shown in Figure 1.
Figure 1. Daily TOA insolation by latitude and day of the year. Phi (Φ) is the Latitude, and theta (Θ) is the day of the year expressed as an angle from zero to 360. Insolation is expressed in watts per square metre. SOURCE.
(As a side note, one thing that is not generally recognized is that the poles during summer get the highest daily average insolation of anywhere on earth. This is because, although they don’t get a lot of insolation even during the summer, they are getting it for 24 hours a day. This makes their daily average insolation much higher than other areas. But I digress …)
Now, the “climate sensitivity” is the relationship between an increase in what is called the “forcing” (the energy that heats the earth, in watts per square metre of earth surface) and the temperature of the earth in degrees Celsius. This is generally expressed as the amount of heating that would result from the forcing increase due to a doubling of CO2. A doubling of CO2 is estimated by the IPCC to increase the TOA forcing by 3.7 watts per metre squared (W/m2). The IPCC claims that the climate sensitivity is on the order of 3°C per doubling of CO2, with an error band from 2°C to 4.5°C.
My insight was that I could compare the winter insolation with the summer insolation. From that I could calculate how much the solar forcing increased from winter to summer. Then I could compare that with the change in temperature from winter to summer, and that would give me the climate sensitivity for each latitude band.
My new falsifiable predictions from my Thunderstorm Thermostat Hypothesis were as follows:
1 The climate sensitivity would be less near the equator than near the poles. This is because the almost-daily afternoon emergence of cumulus and thunderstorms is primarily a tropical phenomenon (although it also occurs in some temperate regions).
2 The sensitivity would be less in latitude bands which are mostly ocean. This is for three reasons. The first is because the ocean warms more slowly than the land, so a change in forcing will heat the land more. The second reason is that the presence of water reduces the effect of increasing forcing, due to energy going into evaporation rather than temperature change. Finally, where there is surface water more clouds and thunderstorms can form more easily.
3 Due to the temperature damping effect of the thunderstorms as explained in my Thunderstorm Thermostat Hypothesis, as well as the increase in cloud albedo from increasing temperatures, the climate sensitivity would be much, much lower than the canonical IPCC climate sensitivity of 3°C from a doubling of CO2.
4 Given the stability of the earth’s climate, the sensitivity would be quite small, with a global average not far from zero.
So those were my predictions. Figure 2 shows my results:
Figure 2. Climate sensitivity by latitude, in 20° bands. Blue bars show the sensitivity in each band. Yellow lines show the standard error in the measurement.
Note that all of my predictions based on my hypothesis have been confirmed. The sensitivity is greatest at the poles. The areas with the most ocean have lower sensitivity than the areas with lots of land. The sensitivity is much smaller than the IPCC value. And finally, the global average is not far from zero.
DISCUSSION
While my results are far below the canonical IPCC values, they are not without precedent in the scientific literature. In CO2-induced global warming: a skeptic’s view of potential climate change, Sherwood Idso gives the results of eight “natural experiments”. These are measurements of changes in temperature and corresponding forcing in various areas of the earth’s surface. The results of his experiments was a sensitivity of 0.3°C per doubling. This is still larger than my result of 0.05°C per doubling, but is much smaller than the IPCC results.
Kerr et al. argued that Idso’s results were incorrect because they failed to allow for the time that it takes the ocean to warm, viz:
A major failing, they say, is the omission of the ocean from Idso’s natural experiments, as he calls them. Those experiments extend over only a few months, while the surface layer of the ocean requires 6 to 8 years to respond significantly to a change in radiation.
I have always found this argument to be specious, for several reasons:
1 The only part of the ocean that is interacting with the atmosphere is the surface skin layer. The temperature of the lower layers is immaterial, as the evaporation, conduction and radiation from the ocean to the atmosphere are solely dependent on the skin layer.
2 The skin layer of the ocean, as well as the top ten metres or so of the ocean, responds quite quickly to increased forcing. It is much warmer in the summer than in the winter. More significantly, it is much warmer in the day than in the night, and in the afternoon than in the morning. It can heat and cool quite rapidly.
3 Heat does not mix downwards in the ocean very well. Warmer water rises to the surface, and cooler water sinks into the depths until it reaches a layer of equal temperature. As a result, waiting a while will not increase the warmth in the lower levels by much.
As a result, I would say that the difference between a year-long experiment such as the one I have done, and a six-year experiment, would be small. Perhaps it might as much as double my climate sensitivity values for the areas that are mostly ocean, or even triple them … but that makes no difference. Even tripled, the average global climate sensitivity would still be only on the order of 0.15°C per CO2 doubling, which is very, very small.
So, those are my results. I hold that they are derivable from my hypothesis that clouds and thunderstorms keep the earth’s temperature within a very narrow level. And I say that these results strongly support my hypothesis. Clouds, thunderstorms, and likely other as-yet unrecognized mechanisms hold the climate sensitivity to a value very near zero. And a corollary of that is that a doubling of CO2 would make a change in global temperature that is so small as to be unmeasurable.
In the Northern Hemisphere, for example, the hemispheric average temperature change winter to summer is about 5°C. This five degree change in temperature results from a winter to summer forcing change of no less than 155 watts/metre squared … and we’re supposed to worry about a forcing change of 3.7 W/m2 from a doubling of CO2???
The Southern Hemisphere shows the IPCC claim to be even more ridiculous. There, a winter to summer change in forcing of 182 W/m2 leads to a 2°C change in temperature … and we’re supposed to believe that a 3.7 W/m2 change in forcing will cause a 3° change in temperature? Even if my results were off by a factor of three, that’s still a cruel joke.
Willis,
“When the forcing goes up in the Southern Hemisphere by 188 W/m2, the surface and atmospheric conditions rearrange themselves such that the surface air temperature only increases by 2°C. That is a very low sensitivity.”
Sure, taken on its face, that suggests very low sensitivity. But there is nothing that says heat is not transported between hemispheres. There is a lot of heat accumulation/loss for the ocean with seasonal changes as well. Some heat in the southern hemisphere is certainly transported to the northern hemisphere in the northern winter and vice-versa in the southern winter, and a lot of heat is absorbed by the ocean in the summer that is released in the winter, which tends to minimize temperature shifts.
Don’t get me wrong Willis, I’m all for trying to use seasonal variation to make estimates of climate sensitivity, independent of climate models, but I think examination the regional temperature changes versus seasonal changes in solar flux will not generate a very accurate value. A more robust estimate could be done (I think) by examining as a heat balance the whole-earth seasonal budget: short wavelength in, short and long wavelength out, seasonal change in ocean heat (Argo) and surface temperatures.
First a clue, I went to the UT that isn’t about to hand multiple honorary diplomas to a failed divinity student.
I currently reside in the DFW area, and said free beer will come with a 100% Not Funded by Big Oil Guarantee (unless my checks for participaring on this blog ever show)
Cheers!
Vukcevic (02:47:48) :
Willis Eschenbach ……….. Warm waters of Arctic are at some depth due to higher salinity (specific gravity)”
http://www.whoi.edu/cms/images/halocline_18008_56197_56788.jpg
Willis,
Answering your question, I think that measuring climate sensitivity across the whole planet makes more sense than comparing seasonal changes per hemisphere, because seasonal effects average out when looking at the entire globe over longer periods of time.
I do agree with your assessment that clouds are a critical controlling factor, and are probably modeled incorrectly by IPCC models.
Can anyone tell me what falsifiable predictions the AGW crowd has stated that would falsify AGW?
johnnythelowery (15:12:51) :
I miss Manuel already. His Iron sun and all that(what ever that is-still can’t figure out what the hell he’s barking on about!). Can I petition for a month long ban instead of life time. I’m sure he’ll behave in the future. It’s just to see a fellow realist get a smack down here at WUWT.
REPLY: I dunno. I warned him about it many times. He just kept trying to sneak in stuff and I got tired of his thread bombing. I will say this for him he was courteous. – Anthony
28 02 2010
Yes you did on several occasions. I’ll bring his name up in the summer to see if I can persuade you to let him back on under probationary terms. Maybe punishment can be metted out, like, having to Watch ‘an inconvenient truth’. in slow motion!
RE: Willis Eschenbach (21:04:24) : “The IPCC, on the other hand, says that a change of 2.5 W/m2 of forcing leads to a change of 2°C in temperature …”
I believe the IPCC may be hiding a simplification in stating a forcing number of this type. According to Stefan-Boltzmann, radiative power forcing is proportional to the fourth power of the absolute temperature. Thus differential power forcing, which is the inverse (1/x) of what they have cited above, must be proportional to four times the cube of the absolute temperature. Thus, I believe, the factor cited above can only valid around some specific reference absolute temperature.
Willis: Was that you at the APPLE CONVENTION who urged the share holders to reject AL GORE on re-election to the board of directors?? I can’t find the article that talked about it. If it was–My heatfelt thank you. The time has long passed when we have to get off our arses and do something! I think there is probably nothing more freightening to AL GORE than the prospect of being challenged in public. Thanks Thanks Thanks.
Would make more sense to use equal area latitudal bands. With nine bands it would be
1: 51° 3’N – 90° 0’N
2: 33° 44’N – 51° 3’N
3: 19° 28’N – 33° 44’N
4: 6° 22’N – 19° 28’N
5: 6° 22’S – 6° 22’N
6: 19° 28’S – 6° 22’S
7: 33° 44’S – 19° 28’S
8: 51° 3’S – 33° 44’S
9: 90° 0’S – 51° 3’S
Shows how small polar regions really are (if A is area south of some latitude, R is Earth radius, then fi=ArcSin(A/(2*Pi*R^2)-1) is latitudal angle – Archimedes, Lambert).
However, it does not address the basic problem of the method. If climate is modelled as a linear time shift invariant system with some definite temperature anomaly response function to a steplike change in radiative forcing, one can look at the corresponding transfer function (Fourier transform of first derivative) in the frequency domain.
It is easy to see that in frequency bands having no excitation, the transfer function can not be determined. Therefore it makes sense to consider spectrum of excitation provided by diurnal & annual cycles.
Frequencies of both cycles are peretty stable, annual one (tropical year) is f1=31.689 nHz, diurnal cycle is f2=11.574 uHz. Excitation at any geographic location is some mixture of the two signals.
Signals like this have discrete spectra with lines at harmonics and sums/differences of them. That is, spectral lines can be located at n*f1+k*f2 (n=…,-2,-1,0,1,2,…; k=…,-2,-1,0,1,2,…) but nowhere else.
Power at harmonics of both f1 & f2 are decreasing sharply as absolute value of harmonic number is increasing, so in practice one does not have too many spectral lines to work with. We can also see that f2>>f1. It means that spectrum of excitation consists of bunches of closely spaced lines with wide gaps among them.
It should be enough to guess value and first (possibly second) derivative of transfer function at several multiples of f2, nothing else. Also, harmonic structure of both annual and diurnal cycles depend on location. Annual cycle is fairly sinusoidal in the Tropics (it does not have much stuff in harmonics) while diurnal cycle has similar problem at the poles. Also, polar annual cycle is close to half sinusoid, so it does not have power at even harmonics. It means that for some locations we have to make with less datapoints or derivatives.
This information is not enough to determine transfer function unconditionally.
One has to make assumptions on the form of transfer function, restricting the choice to a set dependent only on a few parameters. Having done so and given vales and derivatives at some points in the frequency domain the problem might be solvable for parameters. If we are lucky, the solution is unique.
However, as it is well known, assumption is the mother of all f***ups.
Assume for the sake of argument the temperature response to be a first order filter. The response to a steplike change of irradiation of magnitude delta_j is delta_T*(1-exp(t/t0), where delta_T is the final equilibrium temperature anomaly and t0 is relaxation time. We can see that the system gets close to equilibrium only if t>>t0. Initially it only shows a linear rise approximated by delta_T*(t/t0).
If t0 >> 1 year is also assumed (not unreasonable, relaxation time of both large ice sheets and ocean turnover is several millenia), with excitation having no lower frequency component than f1 above, only delta_T/t0 can be estimated, neither delta_T nor t0 alone.
If “climate sensitivity” is defined as delta_T/delta_j, it can NOT be determined by this method (provided relaxation time is much longer than a year). For this end some excitation containing considerably lower frequencies is needed, like Milankovitch cycles, a large volcanic eruption or a Maundner-like solar minimum. With low frequency comes long observation time. We either wait for some more centuries or try to reconstruct historic changes in both forcing and temperature.
On the other hand, if one is only interested in the initial slope of response, delta_T/t0 is more than enough. And as we have seen, it IS measurable by the method described in main article. It tells us how fast temperature would change in the short term, not what its target value vould be, nor how soon it would be approximated. As we have no idea what relaxation time might be, a century may well be considered “short term”.
Also, a first order filter response may be simplicistic. It could be a more complicated filter with several time constants and gains.
We have also assumed linearity. It is either true or not. But the method is suitable to detect at least some nonlinearities. If we see too much energy in a temperature response frequency band where there was no excitation (no frequency component in annual+diurnal insolation anywhere on the globe), it could be interpreted as the indication of some strong nonlinearity in the system. Or some other forcing, independent of cyclic orbital changes.
This analysis has nothing to do with climate as such. Just ordinary signal processing.
TLM (04:28:52), I think you are misunderstanding this article. Willis is not discussing primary CO2 warming. He is discussing the increase in warming (sensitivity) that CO2 warming is supposed to create.
As for the article itself, it certainly opens the door for more research. I think several valid criticisms have been mentioned. But, I’m not sure they would cause a significant change in the numbers. Hopefully, this will give some thoughts for further research (isn’t that what science is all about?).
BTW, I keep seeing more and more support for Miskolczi’s theory. Now we even have a mechanism (tropospheric changes). It will be interesting to see if this progresses.
johnnythelowery (06:42:54) :
I miss Manuel already. His Iron sun and all that(what ever that is-still can’t figure out what the hell he’s barking on about!).
I understand Anthony’s action, Oliver is more than tenuous with his thread relevance at times. I’ve taken him in as a refugee on my blog for now. He has his own solar system thread there for those interested in his theory.
Of relevance to Willis’ theory I have a thread there on OHC and solar variation too.
http://tallbloke.wordpress.com/
If the whole thing works as a first order low pass, then the maximum that temperature can lag energy input is 90 degrees, right? Now where I am it’s six weeks or 45 degrees. And for a simple electrician like me that’s an important number. Means your temperature signal has dropped to 70%. If de phase lag is something like 80 degrees, signal drops to 10%. Maybe that helps, maybe I’m completely on a wrong track.
Willis,
I like your climate theory but I don’t like the physics behind the sums you use to support it.
If one took a filament in a vacuum (say a light bulb) and passed a constant current through it it would heat up to an equilibrium temperature that allowed it to radiate the electrical energy away. If one then did the same with an alternating current of the same average power you would get the same heating and roughly the same peak temperature. In the second case the temperature would oscillate a little with the peak to peak variation depending on the frequency of the electrical current and the thermal capacity of the filament. In the case of a light bulb one sees little fluctuation in temperature yet the input energy is varying by 100% over the cycle.
In the first case we could add a small additional constant current and measure the “forcing”.
Your calculation is equivalent to taking the whole of the power variation in the second case and relating it to the small temperature fluctuation seen in the filament. This would clearly be in no way equivalent.
You may argue that the annual variation in solar energy relative to the earth’s thermal mass is slow compared with domestic electricity passing through a filament but I am pretty sure it not slow enough to make your sums work. As others have pointed out a more sophisticated energy balance calculation is needed.
However it is an interesting line of thought and should be followed up.
johnnythelowery:
Here’s the link:
http://news.cnet.com/8301-31021_3-10459872-260.html
Jimbo (06:10:49) :
“Can anyone tell me what falsifiable predictions the AGW crowd has stated that would falsify AGW?”
Yes. They say difference of ASR (Absorbed Shortwave Radiation) and OLR (Outgoing Longwave Radiation) averaged over the globe is about 0.9 W/m^2. Unfortunately accuracy of (satellite) measurement is too poor to decide the question (systematic error is several W/m^2). If it could be made sharper (error around or below 0.1 W/m^2) and no such difference would be found for several years, it would falsify the theory.
Also, if there is a difference of such magnitude, OHC (Ocean Heat Content) should increase steadily (ocean heat capacity being three orders of magnitude higher than that of atmosphere). It is a relative measurement, so only precision should be improved, but it should anyway. Unfortunately Argo floats are still not up to the task.
So the short anwer to your question is yes, it is falsifiable. The long answer is no, not yet.
TLM,
Your “lid on the saucepan” argument is incorrect.
Increased greenhouse gases make it more difficult for heat to escape, so temperature rises to keep equilibrium. Heat is not “trapped.” It finds it’s way out.
There are longer term effects of ocean equilibration, but over the last few years there is no sign that ocean heat content is increasing.
Good stuff Willis.
I think you are using TOA solar insolation. I have the Albedo numbers by 10 degree latitude bands which could be built in as well and improve the results.
The high Arctic has the highest solar insolation in the summer but it also has the highest Albedo at 0.5 – approximately 50% of the summer solar insolation is just reflected off into space, significantly reducing the surface solar insolation input. Whereas in the equatorial regions, the Albedo is only about 0.250
The Albedos vary between the seasons as well. Between 60N to 70N, the summer Albedo is about 0.4 while the winter Albedo is about 0.75 (the low solar incidence angle means the majority of what little solar insolation there is in the winter, is just reflected off into space as well). As you move closer to the equator, the seasonal change is less. The range provided in each latitude band provides a rough gauge of how much Albedo changes between the summer and winter.
This would likely provide different values for the sensitivities by latitude. (I think one would have to run the numbers to say how the amounts and the relative differentials would change).
http://img706.imageshack.us/img706/2697/albedomodel.png
Willis
If it wouldn’t be too difficult, would you also do a ‘figure one’ sometime for what it looked like at the deepest part of the last glacial period? And put these two together on a brief post?
Great stuff!
tallbloke (07:54:45) :
johnnythelowery (06:42:54) :
I miss Manuel already. His Iron sun and all that(what ever that is-still can’t figure out what the hell he’s barking on about!).
I understand Anthony’s action, Oliver is more than tenuous with his thread relevance at times. I’ve taken him in as a refugee on my blog for now. He has his own solar system thread there for those interested in his theory.
Of relevance to Willis’ theory I have a thread there on OHC and solar variation too.
http://tallbloke.wordpress.com/
Hi Tallbloke: Total fair doos on Anthony’s part. Let me ask a dumb question
(no, don’t know him from Adam) : Does his idea have any relevance to the issues here, AGW, solar forcings, etc? Would the composition of the sun (Iron) have any relevance to the general climate debate here? I don’t understand what his idea is, and why an obviously intelligent guy ignores warnings we all have read to keep harping on about it here. Thanks for taking him in and I’ll definately be visiting.
Willis!
Your a genius!.I took me some time understanding what you really is measuring.By this you leave the proof to the AGWers to explain and calculate why the actual difference in radiance balance are not bigger.
The warming “depot” in the ground doesnt help them,neither does the oceans.Eather way you rationalized them and quantified ther influence as a lump toghether.The probability that the “radiance delay” or boost from oceans and ground could vary to a degree that significantly effects your calculations is highly unbelivieble.
You took the easy but smart way to point this out.Another forgotten factor is the expansion of the atmosphere if it gets hotter another non estimatet cooling factor.The planet is a smart construction with a multiple backup security systems.Not the same sensitive house of cards as the AGW alarmism.
Yoy have great friends in Roy Spencer Lindzen and Choi and also Christy you are all pointing in the same direction.
Willis, Your order-of-magnitude analysis of complex global weather systems is far more informative than manipulating huge quantities of intensive properties like atmosperic and SSL temperatures (much of which has been corrupted). Better to have an understanding of the detail, before it buries you! Well done!
Hi Tallbloke: Total fair doos on Anthony’s part. Let me ask a dumb question (no, don’t know Oliver from Adam) : Does his idea have any relevance to the issues here: AGW, solar forcings, etc? Would the composition of the sun (Neutron star core/Iron) have any relevance to the general climate debate here? I don’t understand what his idea is, and why an obviously intelligent guy ignores warnings we all have read to keep harping on about it here. Thanks for taking him in and I’ll definately be visiting you over there.
This has been well understood for decades. Hansen talked about Polar Amplification a long time ago.
This also is a well understood feature of weather. San Jose is a lot hotter than San Francisco because of proximity to the ocean.
Cirrus clouds are believed to cause more warming than cooling. Other clouds block incoming SW and outgoing LW. There isn’t a simple answer for this and climate models don’t do a good job with them.
Well that is the $64,000 question, but I don’t think this simple analysis answers it. There are many complex factors which go into the equation.
John Whitman (03:51:15)
Glad someone noticed …
w.
Thanks Sean. The APPLE CORP. BOARD OF DIRECTORS AND SHAREHOLDER MEETING ‘Gadfly’ is SHELTON EHRLICH…..
‘………………….At the first opportunity for audience participation just several minutes into the proceeding, a longtime and well-known Apple shareholder–some would say gadfly–who introduced himself as Shelton Ehrlich, stood at the microphone and urged against Gore’s re-election to the board. Gore “has become a laughingstock. The glaciers have not melted,” Ehrlich said, referring to Gore’s views on global warming. “If his advice he gives to Apple is as faulty as his views on the environment then he doesn’t need to be re-elected……….” Thanks SHelton……………..whoever you are.