Discussion > An experimental demo of GHE.
(Reposted from the what if dragonslayers are right thread)
The fact that the physics is flawed is simply evidenced by spacecraft measurements of the surface temperature of the Moon - an airless world of the same composition and insolation as the Earth.":
Jan 5, 2013 at 4:43 PM Roger Longstaff
(This thread: Jan 5, 2013 at 5:29 PM Roger Longstaff )
Roger - do you have a reference to the lunar surface temperature, preferably from NASA or NASA sponsored investigators?
RKS mentioned a single value (but without saying if it was an average over the entire lunar surface and over the entire lunar day+night). He seems to have buggered off without responding to a request for a reference to this figure and how it was measured/calculated. The only reference I found from what he had said referred just to the lunar equator - and the website for the investigation seemed to be out of action.
BTW, is the Earth really the same composition as the Moon? My back garden at present does not look much like lunar dust. And the English Channel looks even less like lunar dust.
Also, I can imagine that the difference between the 24 hours of Earth's day+night and the 24 × 28 hours of the Moon's day + night might also make things different.
Martin A
As I've said before, Slayers theories to me are a bit like UFO stories. I would truly love them to be real, which is why I'm extra extra tough on them, because there's none so easy to fool as the fool that wants to believe something.
Wouldn't it be exciting if the pressure theory was even partially correct or a major contributor?
TheBigYinJames
Martin,
The recent Diviner data from JPL appear near the top of this thread:
http://tallbloke.wordpress.com/2012/03/28/empirical-results-from-diviner-confirm-s-b-law-was-misapplied-to-moon/
Roger Longstaff
Roger, in asking for comments on your 'Third Pillar' (from the "what if the slayers are right?" thread):
"The CAGW hypothesis is predicated on a "greenhouse effect" (GHE) in which the Earth's atmosphere raises the surface temperature of the planet by 33 degrees Kelvin above that of an airless planet, and that anthropogenic emissions of carbon dioxide will increase the surface temperature by a dangerous amount - 2 degrees or more. This is hopelessly flawed physics, partly due to incorrect mathematics (not using Holder's inequality) and partly due to the confusion between diurnal thermal equilibrium and thermodynamic equilibrium. The fact that the physics is flawed is simply evidenced by spacecraft measurements of the surface temperature of the Moon - an airless world of the same composition and insolation as the Earth."
you make me wonder. I take it you are a physicist. So why would you need help to describe what must be bread-and-butter stuff?
BitBucket
Bitbucket,
I you read the last couple of pages you will understand why! I am looking for a simple explanation for flawed physics, and so far we have established that the IPCC got their mathematics wrong (Holder's inequality). What follows has been largely a discussion about the N&Z stuff, which is not simple, and, as I said, I don't buy all of it (the cause and effect relationship of albedo seemingly being based upon intuition, and a remarkably impressive curve fit for 8 planets).
However, is the Holder's inequality cock up sufficient to discredit all of the IPCC physics? Yes, it probably is.
Roger Longstaff
There has been such a huge input of information to this thread that it will take me a week to decide what my new opinion is on the GHE ^.^
However may I ask yet another question of the long suffering Big Yin (and any others)?
AR3 included a reference to the "fact" that effect of CO2 (and other greenhouse gases) was logarithmic. This has since been swept under the the politically correct carpet and has disappeared.
a year or so back alecm (probably in the former identity as spartacus is free) explained to me that he had been involved in the design of industrial furnaces. alec said that such furnaces are designed on the assumption that the effect of CO2 is zero above 200 ppm.
When I first started reading about CO2 I read articles by Richard Lindzen and he also stated that the effect of CO2 reduced as the atmospheric level increased.
I do not see anything in the above posts that acknowledges or explains this?
Dung
" why does it get immediately (i.e. not convectively) warmer when clouds come in over a clear sky?"
I agree that clouds probably do have an insulation effect, as you suggest. However, I think the magnitude of this effect is wildly exaggerated. From my observations, the main reason why temperatures rise quickly when clouds come overhead is because the clouds are being brought in by milder air, which also tends to displace the colder air at ground level. Hence the immediate temperature rise. A good example of how weak the LW radiation bounced back off clouds is when warm westerlies come over the highlands in winter. Temperatures at the 1000ft level can typically rise by 5 to 10C in a few hours. However, in sheltered glens and valleys (usually perpendicular to the wind direction but not always) the cold sub-zero air on the valley floor can persist all day. I have photographic evidence of this - the trees at 1000ft are dark and bare, while - low level trees still white with thick frost 6 hours after the warm winds came in. Back radiation may exist, but its effect is wildly exaggerated. Right now, the sun has been down for 7 hours, and there is not a cloud in the night sky, yet the temperature is 9.5C, which is 10-15C more than I would expect for early January. Where has the warmth come from? From looking at recent jet stream tracks, probably the seas off Florida or Bermuda. Nothing to do with back radiation from passing clouds or trace CO2.
lapogus
I also question the 25% statistic, I always thought that the accepted figure was between 7 and 10%. And Dung asks a good question about the logarithmic effect; why does no one mention this any more? I always understood that any increases above 250-300ppm were as good as negligible.
lapogus
The recent Diviner data from JPL appear near the top of this thread:http://tallbloke.wordpress.com/2012/03/28/empirical-results-from-diviner-confirm-s-b-law-was-misapplied-to-moon/
Jan 5, 2013 at 8:17 PM | Roger Longstaff
Thanks Roger.
I saw a sentence saying "Well, at least I was right about one thing; the empirical data is the most important. I’ve just had an update via email to say the latest empirical estimate of mean temperature for the Moon is 192-197K. " and some data for the mean temp at the equator.
The URL's that seem to point to actual data, like diviner.ucla.edu/publications.shtml seem to get no response.
Martin A
Lapogus - On a clear night without much wind the temperature will fall sharply at first until the ground temp (which cools the air of course) falls lower than the underlying soil temp. At this point heat transfer by conduction upwards will moderate any further fall of ground temp, and thus screen temp.
Low cloud (<2000 feet) will often be slightly warmer than the ground (an inversion having formed) and a balance of effects takes place with IR arriving from the cloud. This happens with no change of airmass or dew-point of the air.
This is most dramatic, when you have had fog all day which never cleared with the current bun shining directly on it, but clears in an hour or two during the night when low cloud moves over the top.
Retired Dave
...effect of CO2 (and other greenhouse gases) was logarithmic.(...)
Jan 5, 2013 at 10:37 PM Dung
I once asked about the logarithmic response on SOD. It seemed to me that if something has a simple form like this, it must come as the elegant solution of a simple formulation of a model and I was puzzled as to why it was not widely known.
I was disappointed to read from the responses that it came from:
- Simulating things in a model (a GCM, I think) for various CO2 levels.
- Finding that a log curve could approximate the points coming from the simulations.
Martin A
RKS - Could you please give a reference (ideally to a NASA report or at least by NASA sponsored researchers) that details this figure and how it was obtained. I am guessing it is an average of the lunar surface temperature measurements over the whole surface and over a complete lunar day.
For estimating the total power radiated by the Moon, the average of the fourth power of T would be more relevant. Because of the huge range of lunar surface temperatures (eg I've seen 30°K - 400°K quoted), you can expect the (average of T^4) to be appreciably different from {(the average of T)^4}. I guess it's too much to hope for that they have published (average of T^4).
Jan 2, 2013 at 7:50 PM | Martin A>>>>>
Hi Martin.
Sorry to take so long responding but I'v been away for a while
The published information about mean lunar temperatures is the paper by Vasavada et al. (2012), where they show a typical mufti-year diurnal course of the Moon surface temperature at the Lunar Equator. This curves yields an average value of 213K, which is about 57K lower than the estimate derived from the simple SB equation. If the mean temperature at the lunar equator (which is the warmest latitude on the Moon) is 213K, then the global average temperature must be lower than that, and it is 197.3K ...
Reference: Vasavada, A. R., J. L. Bandfield, B. T. Greenhagen, P. O. Hayne, M. A. Siegler, J. P. Williams and D. A. Paige, (2012), Lunar equatorial surface temperatures and regolith properties from the Diviner Lunar Radiometer Experiment, J. Geophys. Research, 117, E00H18, doi:10.1029/2011JE003987.
Also here:-
Ashwin Vavasada: Lunar equatorial surface temperatures and regolith properties from the Diviner Lunar Radiometer Experiment
http://tallbloke.wordpress.com/?s=vasavada
As Ned Nikolov said in a recent email to me:-
"The 197K mean temperature of the Moon is discussed in our 25+ page paper that is currently under review with a major atmospheric journal. That figure is supported by 3 lines of evidence: Diviner measurements, NASA thermophysical models of the Moon, and purely theoretical considerations accounting for Holder's inequality and proper integration of the SB radiation law over a sphere ... You'll have to wait for our paper to come out to see all the details. But trust me, It's a bulletproof case!"
This of course means that the Earth, with an identical regolith, needs to have it's mean temperature raised by 91K to get to the present 288K.
The hypothetical greenhouse effect by way of back radiation [preached to us so often by AGW zealots] simply won't fit that particular bill.
Some here have poured scorn on N&Z's use of the Ideal Gas Law but forget that it tells us that the gas's kinetic energy is a product of pressure and volume [much the same as with star formation]. As with star formation an external form of energy, either insolation or, with star formation, radiation from the cosmic background temperature of 2.7K, is required to act on the energised molecules at the base of the atmospheric column to produce heat. But don't just take my word for it - look up the many threads at Tallbloke under the search terms 'Nikolov and Zeller' where the details are discussed calmly and objectively [As opposed to some of the hand waving on this thread]
Some here [deliberately?] misquote N&Z by trying to conflate localized weather to their theory when they explicitly state they are dealing in the long term [multi annual]. Perhaps it's simply that such people have not really bothered to either read or at least comprehend what was said.
The only reason I've mentioned N&Z on this thread is because I don't see how misnamed 'greenhouse gases' can have even a small effect, let alone the 91K indicated by NASA Diviner, and I think Rhoda is quite right to demand measured proof of the effect.
Some contributors here merely wave their arms and say it is not measurable as an atmospheric effect, whilst at the same time proclaiming their 'belief' in the effect [but to a lesser degree than those proposing CAGW]. And anybody who disagrees with GHE [again a total misnomer for that which bears no relation whatsoever to an actual greenhouse - or tin shed come to that] is a low life 'dragon slayer' and should be ridiculed and banished from the threads.
Thanks to ChrisM and Mike Jackson by the way for being prepared to show a little objectivity when dealing with 'non consensus' ideas. It's no good trying to be sceptical of AGW science if you have to accept the basis for the science in the first place.
RKS
I you read the last couple of pages you will understand why! I am looking for a simple explanation for flawed physics, and so far we have established that the IPCC got their mathematics wrong (Holder's inequality). What follows has been largely a discussion about the N&Z stuff, which is not simple, and, as I said, I don't buy all of it (the cause and effect relationship of albedo seemingly being based upon intuition, and a remarkably impressive curve fit for 8 planets).
However, is the Holder's inequality cock up sufficient to discredit all of the IPCC physics? Yes, it probably is.
Jan 5, 2013 at 9:09 PM | Roger Longstaff>>>>
Nice to see you posting again Roger.
Ned Nikolov informs me there will be no part 2 Q&A post at Tallbloke for UTC as they're a bit too busy preparing for peer review at present and won't have time to deal with blogs.
As for the 8 planet curve fit, don't forget an awful lot of good science came from deriving a theory from measured data. Pi and Pythagora' theorem had to come from some initial ancient set of measurements, as must many other constants. See Fig.6 Temperature/potential temperature ratio as a function of atmospheric pressure according to the Poisson formula based on the Gas Law (Po = 100 kPa.). Note
the striking similarity in shape with the 8 planet curve in Fig. 5.
The new paper is 25 pages long and should, I hope, answer all questions in detail. He tells me he now regards the paper as 'bomb proof'.
best regards,
RKS
Well said RKS.
Roger Longstaff
[oops - posted on wrong thread]
Martin A
As I said, the mud in my back garden (or the seawater in the English Channel) seems to me vastly different in these properties from the lunar dust in the Sea of Tranquility.
I think making comparisons between Earth and other planets (such as Harry Huffman has done) and the Earth and planetary satellites is likely to be very enlightening. But because of the thermal and optical differences between the surface of the Earth and the Moon, I find it very hard to believe that observations of the Moon's temperature can taken as applying to the Earth where nothing had changed except for the deletion of the GHE.
Jan 6, 2013 at 9:09 AM | Martin A>>>>>
Being made of exactly the same material surely the surface of an airless Earth would possess the same properties as the Moon - why would it not? Even AGW hypothesis demands we start from a condition of airless Earth and then add atmosphere to achieve temperature rise to 288K. To compare an Earth with atmosphere to the airless Moon is to compare chalk with cheese. Once we have obtained the contribution of atmosphere any comparison to the Moon is pointless and redundant.
Also with a spinning globe with heating to one side - the mean temperature would be the same at whatever rate of rotation. Slow it down, the hot side gets hotter - the dark side gets colder, speed it up, the hot side gets less hot - the dark side gets less cold - the mean temperature remains the same. again, why would it not?
Interesting discussion!
RKS
RKS, re. your second post (our first ones crossed).
Glad you are here, I felt I was on my own yesterday. I have not looked at N&Z for several months, so thanks for clearing up the point about UTC Part 2. I await it with great interest. If they give a reasonable explanation for albedo I will become a fully paid up "slayer" (whatever the hell that is).
In my original post yesterday you will see that I am trying to construct a single page rebuttal for the CAGW hypothesis. This must be purely factual, and unarguable. The stuff on fiddled data and useless models is easy - which leaves the physics.
I am now minded to go with Holder's inequality, on the basis that in any calculation if you get the first step wrong all of the results and conclusions that follow are meaningless nonsense. Do you agree, and do you have any suggestions?
Best regards, Roger
Roger Longstaff
To be fair to Rhoda and trying not to stray too far from the thread topic I propose a little experiment.
Take a tall room with well insulated sides and floor and with a black refrigerated ceiling.
Cover the floor with bog standard garden loam.
Fit a high power downward reflected lamp of around 6000K colour temp to the ceiling.
Fill the room with nitrogen at a pressure of 1 atmosphere.
Run the lamp for say one day to establish steady convection currents and measure the surface of the loam with thermocouples.
Add CO2 to the room at a concentration of 200ppm.
repeat the measurement run.
Add additional CO2 to the room to a concentration of 400ppm.
Repeat the measurement run.
In agreement with AGW hypothesis, any LW back radiation from the CO2 should raise the temperature at the surface of the loam.
Just a thought!
RKS
I am now minded to go with Holder's inequality, on the basis that in any calculation if you get the first step wrong all of the results and conclusions that follow are meaningless nonsense. Do you agree, and do you have any suggestions?
Best regards, Roger
Jan 6, 2013 at 9:42 AM | Roger Longstaff>>>>
I'm inclined to agree there Roger.
Although the 'science' behind AGW is more hypothesis than theory, you only have to falsify a theory once to send it back to the drawing board.
RKS
The basic request made by Rhoda, the originator of this discussion was for an experiment to prove or disprove the GHE. I give credit to RKS for being the first person to suggest one since my own attempt several pages back. It seems to me that despite the truly wonderful exchange of ideas and theories in this discussion, we would benefit more by trying to agree on and refine an experiment that would indeed test the GHE or AN ASPECT OF IT. I am sure we could get that experiment run in a universtity lab somewhere.
Such an experiment run first (as RKS suggested) with zero CO2 and then with increasing CO2 would test both the effects of CO2 and also the logarithmic aspect.
Dung
Martin A:
I once asked about the logarithmic response on SOD. It seemed to me that if something has a simple form like this, it must come as the elegant solution of a simple formulation of a model and I was puzzled as to why it was not widely known.I was disappointed to read from the responses that it came from:
- Simulating things in a model (a GCM, I think) for various CO2 levels.
- Finding that a log curve could approximate the points coming from the simulations.
Fascinating. Do you remember where that was on SoD? Were papers cited?
Richard Drake
RKS - Totally agree with you, especially your last sentence in the 2.26 am comment.
"It's no good trying to be sceptical of AGW science if you have to accept the basis for the science in the first place."
Surely another case of the science not being settled.
Retired Dave
Interesting post by Stephen Wilde:- Fellow of the Royal Meteorological Society
The Myth of ‘Backradiation’
http://tallbloke.wordpress.com/2012/02/25/stephen-wilde-the-myth-of-backradiation/
Runs along similar lines to N&Z and might help explain some aspects of their theory.
RKS
Holder's inequality has been mentioned a bit recently.
It's always seemed pretty obvious to me that integrating a thing then raising the integral to the 4th power will generally give quite a different answer from integrating the 4th power of the same thing.
Consider a function
f(x) = 0, for 0 < x < 0.5;
f(x) = 2, for 0.5 < x < 1.
[my keyboard does not have "less than or equal" symbols but you get the idea]
Integrate it from x = 0 to x = 1 gives integral = 0×0.5 + 2×0.5 = 1.
Raise the value of the integral ( = 1) to 4th power.
Result is [Integral of (f(x)]^4 = 1.
Now consider the the function raised to the fourth power: g(x) = f(x).f(x).f(x).f(x) = f(x)^4.
g(x) = 0^4 = 0, 0 < x < 0.5;
g(x) = 2^4 = 16, 0.5 < x < 1.
Integrating g(x) from x = 0 to x = 1 gives 0×0.5 + 16×0.5 = 8. ie
Integral of [f(x)^4] = 8.
So integrating (in this special case) then raising to the 4th power gives 1/8 the value you get from raising to the 4th power then integrating.
This illustrates that using average temperatures in radiation calculations gives the possibility of being misled.
Martin A
Paul,
A quick search found that the latest empirical estimate of mean temperature for the Moon is 192-197K. This figure pretty much splits the difference between the old 255K and new theoretical figure of 155-157K. However, the new figure is calculated without a term for regolith heat retention term in the equations, which clearly would raise the mean temperature somewhat.