Discussion > An experimental demo of GHE.
RKS - do you have a reference for the average lunar temp. calc you mentioned? I did a quick search and found this but couldn't find it. This seemed the most relevant result that came up:
http://davidappell.blogspot.co.uk/2012/05/re-diviner-result.html?m=1
Apologies if this has been bottomed out earlier in the discussion.
Jan 2, 2013 at 1:20 AM | not banned yet>>>>
The fact that the measured average temperature of the Moon, and therefore the bare atmosphere less Earth, is in fact 197K, will provide enormous difficulty for those proposing that GHE raises global temperature by 33K whereas the real contribution of atmosphere is, in fact, 91K.
All estimates of the contribution of CO2, even by AGW-Lite Lukewarmists, is based on the 33K value of GHE. They'll just have to look for another reason for that 91K, and the Nikolov and Zeller UTC theory, based on measured data on many atmospheric bodies within the solar system, show the effect of insolation on lower tropospheric pressure induced kinetic energy - in other words by application of the Ideal Gas Laws.
I include a reference to the UTC PDF below and include links to the Lunar Diviner paper plus a discussion post by Ned Nikolov on how the Lunar Diviner results have implications for the way the S-B standard Equation is used to estimate global temperature.
UTC PDF
http://www.wcrp-climate.org/conference2011/posters/C7/C7_Nikolov_M15A.pdf
Lunar equatorial surface temperatures and regolith properties
from the Diviner Lunar Radiometer Experiment
http://tallbloke.files.wordpress.com/2012/04/lunar-equatorial-surface-temperature_2012.pdf
Ned Nikolov: Implications of DIVINER results for the S-B standard equation
http://tallbloke.wordpress.com/2012/05/01/ned-nikolov-implications-of-diviner-results-for-the-s-b-standard-equation/
Hope this is useful.
RKS
Jan 2, 2013 at 1:20 AM | not banned yet>>>>
A bit more information on Lunar Diviner data etc:-
Empirical results from DIVINER confirm S-B Law was misapplied to Moon
http://tallbloke.wordpress.com/2012/03/28/empirical-results-from-diviner-confirm-s-b-law-was-misapplied-to-moon/
RKS
RKS - thanks for the links. I'll follow them up shortly.
not banned yet
Dear Fellow BH Posters,
This sub-discussion has avalanched in a very interesting fashion. Some interesting questions that I cannot answer have been posed by people who have arrived in the middle of this sub-thread.
This has even resulted in apparent annoyance, as if I were refusing to respond to questions to avoid debate.
Therefore I shall recap at this point:
1. I am 100% in agreement with Rhoda, Dung, et al, that until the greenhouse effect (GHE) can be verified by direct physical observation and measurement, it is nothing more than a hypothesis.
2. The GHE is often modelled as a black body (BB) at constant temperature, surrounded by a thin shell of greenhouse gasses (GG), transparent to incoming radiation from the Sun and intercepting and re-radiating outgoing IR in all directions.
3. I commented to Dung that this simple model for the GHE can be analysed by simple physical principles without invoking notions such as energy carried by "back radiation" heating things. Dung asked me to clarify and explain further and I did my best to respond.
4. I think that this model is so over-simplified and neglects so many important effects that it provides, at best, a plausibility argument for the GHE. Any numbers (eg +33°C) coming from it are, from my viewpoint, best regarded as guesses - nothing more than that. I am not defending the model as an accurate representation of reality - quite the reverse. So please excuse me from responding to questions that point out that the model neglects important effects or oversimplifies things - I agree.
5. Despite the model being a crude (perhaps uselessly crude) representation of reality, I think it is erroneous to state (as the Dragon Slayers do) that it violates the laws of physics. The analysis frequently presented by "climate scientists" does not make sense to me - they talk of "trapping radiation", "back radiation" warming things, and other things that sound like nonsense to me, so I can understand people objecting that the analysis is wrong.
However, the model can be analysed very simply by assuming that, in thermal equilibrium, the incoming power arriving at the black body and conveyed by radiation from the sun equals the net outgoing power radiated by the black body. The temperature of the black body, warmed by incoming solar radiation, rises to whatever temperature is needed for equilibrium. No need to use arguments that invite accusations of violating the laws of thermodynamics.
I really must get around to doing a write-up so that people can follow the analysis in detail (or point out my misconceptions if there are any). I had thought that it was widely known but the discussion suggests it is less widely known than I had assumed.
Martin A
Jan 2, 2013 at 8:43 AM | Martin A>>>>
Thanks for clarifying your position regarding back radiation, although your second to last paragraph simply refers to incoming and outgoing radiation from the black body warmed by solar radiation - no mention of back radiation from a GHG.
So far, no-one at BH, in spite of numerous attempts, has succeeded in outlining a working demo of back radiation as a cause of GHE, which is what the whole thrust of the AGW argument is about.
RKS
Martin A
I hope you didn't take my reply as being annoyed, I certainly wasn't. I was trying to get a handle on exactly what you were proposing and from what standpoint; which you have clarified (probably not for the first time, but there is a lot to go through here). Apologies if you took it that way, it is difficult to put a facial expression and tone of voice into text alone (he said softly with a smile).
Anyway thanks for your efforts, but I even dreamt about this last night and it occurred to me that AlecM's double pyrometer test touches on this with there being zero radiation measured (as I think he says). Even this little part of the model is very complex and who knows how to model it?
I think we both agree that even here on what should be a simple issue the models are probably not that good. In a another part of my life I collect 1\1250 scale ships and there is a range of quality there too, current climate models seem to be scratch built by novices compared to the required best German stuff currently available. See here if you're vaguely interested (trying not to be wildly off topic by mentioning this only once)
http://www.navis-neptun.de/produkte/datenbank/t1102v_e.html
SandyS
Woo, what a thread!
Can I just make a point about the Lunar Diviner stuff?
Since the moon has no atmosphere, the measured surface temperature is the temperature of the rock - this cannot be easily compared with the 'near surface air temperature' that we use on earth. Also saying 'the moon and earth are made of similar materials' is true, yet ignores the much higher albedo of the moon.
Also, I'm not sure RKS's link to Tallbloke's article proves what he thinks it does - all it proves is you can't sum averages, something we all agreed on in the many threads we discussed the energy imbalance. We already know you can't treat the earth (or the moon) as a single monolithic black body object and use single average figures to describe it - this goes doubly for the earth which has a moving convective atmophere and heat sinks.
As I said on the thread where I went through the basic average SB cacluations, all it proves is there is enough energy in the system, not that it actually happens that way - the fallacy RKS falls into is thinking you have to disprove the simple back body model is correct in order to disprove the GHE. But to do so he has to throw away two centuries of physics.
TheBigYinJames
Jan 2, 2013 at 10:49 AM | TheBigYinJames>>>>
You didn't read or comprehend anything that was said.
The Earth and Moon are comprised of identical regoliths - WITHOUT ATMOSPHERE their albedos are also identical. Why on earth are you comparing the albedo of the moon with that of the Earth WITH ATMOSPHERE?
Did you look at the data from Lunar Diviner which shows, by actual measurements that the Lunar MEAN temperature, and therefore bare Earth mean temperature, is 197K?
Did you look CAREFULLY at the detailed calculations By the physicists Nikolov and Keller in determining the effect of atmosphere on a celestial body?
Did you look at the results in the paper by the NASA JPL scientist on the results of the Lunar Diviner MEASURED data?
Did you actually bother to read and digest Nikolov and Keller's post on the implications for S-B equations relevant to a celestial body?
And it doesn't disprove anything other than the misuse of S-B when measuring Lunar [or Earth] mean temperature - Diviner actually measures it.
As with the IPCC approach, you must first determine conditions on BOTH bodies with the absence of atmosphere. Only then can you see the effect of adding an atmosphere. For some reason you want to jump over that step and compare apples with oranges.
Instead of saying RKS says this or that, why not give a detailed critique of the papers referenced and backed up by sound measurements as opposed to estimated values.
The previous calculated Lunar temperature, using S-B, is PROVED to be wrong by MEASURED data.
I'm sorry if you think that throws away two centuries of physics [which of course it does not] but that is a FACT.
RKS
RKS, too many adhoms in there for me.
TheBigYinJames
RKS (9:29 AM):
So far, no-one at BH, in spite of numerous attempts, has succeeded in outlining a working demo of back radiation as a cause of GHE, which is what the whole thrust of the AGW argument is about.
I would deeply disagree with this sentence if I came across it in isolation. But as a response to Martin A's brilliant post of 8:43 AM it seems particularly weird. Surely Martin is agreeing with you and many others that back radiation, as used by some climate scientists, makes no sense. It cannot be "a cause of the GHE" let alone "what the whole thrust of the AGW argument is about" or we have the simplest slam dunk in scientific history.
This is called a straw man argument - normally entered into because of the weaknesses of one's real argument. But the sceptical position is much stronger than this misdirection would imply.
Richard Drake
To go back to rhoda's original question - there are certain types of experiment that cannot be done in a controlled lab condition because the effects are only measurable in quantity. This is a practical problem with the experiment, it doesn't prove or disprove the effect - neither does it make it 'unscientific'.
An example - say you as a psyhcologist have a hypothesis that in goups of over 10,000 people in a confined space, if someone at the edge shouts "fire" then 2 people per thousand will be trampled. If someone at the centre of the throng shoults "fire" then 10 people per thousand will be trampled. For groups of under 10,000, then this effect does not manifest.
It's a fair hypothesis, but can you prove it in a lab? Can you fit 10,000 people in your lab? Does this mean that the hypothesis is 'unscientific' simply because you practically cannot do the experiment?
You *could* do it - if you had unlimited resources and time. The same way as we could test the GHE by grabbing a handy planetoid and doing the actual experiment.
As a side note, you *could* do the 10,000 people experiment by using numerical modelling - programming a 'behaviour' into numerical components and running the simulation.
So, to get back to climate - is there an experiment which you can practically do to test or observe the GHE? I have a hunch there is not, because the effect is tiny and only measurable over large volumes and energy fluxes. Again, I don't think this invalidates or validates GHE as a theory - but the practicalities of the experiment do not invalidate it as a test, so it does not fail the Popper criteria.
TheBigYinJames
Martin A
I hope you didn't take my reply as being annoyed, I certainly wasn't. (...)
Jan 2, 2013 at 9:34 AM SandyS
SandyS - not at all. I took your comments as pleasant and light hearted.
Martin A
RKS -
Thanks for clarifying your position regarding back radiation, although your second to last paragraph simply refers to incoming and outgoing radiation from the black body warmed by solar radiation - no mention of back radiation from a GHG. (...)
Jan 2, 2013 at 9:29 AM RKS
Yes, but please re-read the start of my penultimate paragraph and note the word that I probably did not sufficiently emphasise or explain.
What I actually said was:
"However, the model can be analysed very simply by assuming that, in thermal equilibrium, the incoming power arriving at the black body and conveyed by radiation from the sun equals the net outgoing power radiated by the black body."
(emphasis added)
The net power means the power radiated by the BB that escapes the system. It is the total power radiated by the BB, less the power that comes back to it and has to be re-radiated.
It's best I write it up so it can be followed step by step. Please reserve judgement until then.
Martin A
RKS, too many adhoms in there for me.
Jan 2, 2013 at 11:46 AM | TheBigYinJames>>>>
Plenty of questions directed at you but adhoms? - please quote.
RKS
RKS (9:29 AM):
So far, no-one at BH, in spite of numerous attempts, has succeeded in outlining a working demo of back radiation as a cause of GHE, which is what the whole thrust of the AGW argument is about.
I would deeply disagree with this sentence if I came across it in isolation. But as a response to Martin A's brilliant post of 8:43 AM it seems particularly weird. Surely Martin is agreeing with you and many others that back radiation, as used by some climate scientists, makes no sense. It cannot be "a cause of the GHE" let alone "what the whole thrust of the AGW argument is about" or we have the simplest slam dunk in scientific history.
This is called a straw man argument - normally entered into because of the weaknesses of one's real argument. But the sceptical position is much stronger than this misdirection would imply.
Jan 2, 2013 at 11:49 AM | Richard Drake>>>>
what is the title of the thread Richard?
My comment was referenced to that!
RKS
[deleted - found what I had asked for]
Martin A
- please quote.
Jan 2, 2013 at 5:40 PM RKS
"You didn't read or comprehend anything that was said."
"Why on earth are you (...) ?"
"Did you look CAREFULLY at the detailed calculations(...)?"
"Did you look at the results in the paper by (...)?"
"Did you actually bother to read and digest(...)?"
"For some reason you want to jump over that step and compare apples with oranges."
Big Oil
Thanks Big Oil, but I didn't really want to get RKS's blood pressure up any more than it is, which is why I left it ! :)
TheBigYinJames
(...)
Do you agree with the MEASURED Lunar temperature of 197K as MEASURED by the NASA Lunar Diviner probe, and if not could you explain why please? (...)
Jan 1, 2013 at 5:33 PM RKS
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).
Martin A
"So, to get back to climate - is there an experiment which you can practically do to test or observe the GHE? I have a hunch there is not, because the effect is tiny and only measurable over large volumes and energy fluxes. Again, I don't think this invalidates or validates GHE as a theory - but the practicalities of the experiment do not invalidate it as a test, so it does not fail the Popper criteria."
Well, BigYin, that's fine. But those who can neither measure the effect nor show it in action surely don't expect me to believe that it can boil me or drown me. They are asking me to believe in a hypothesis they cannot prove nor propose falsification criteria for. If there is no higher standard of proof, this ranks below the tooth fairy, for at least there used to be a coin under my pillow when I left a tooth there. In the case of climate, they ask me to believe there WILL be a coin, someday. It will not do.
rhoda
Rhoda - I think they are saying that the effect will only be evident after 100 or so years. That is consistent with what guys like Carrick say over at Lucia's Blackboard. The Nick Stokes fantasists and BBD and the Bucket person can wail all they like.
diogenes
RKS:
what is the title of the thread Richard?My comment was referenced to that!
There is nothing in the title about back radiation. You insisted on casting back radiation as the "cause of GHE, which is what the whole thrust of the AGW argument is about" - when Martin had just agreed it's a nonsense way of explaining the GHE.
So why all this effort on a straw man? I continue to call that misdirection.
Richard Drake
I'm not apologising for the lack of GHE experiment, or justifying it as being taken as fact without it, just noting that the lack of practical experimentation doesn't invalidate an effect being modelled. We understand cosmology, but can't experiment with it.
With GHE, there is a proposed mechanism which seems to make sense. It might still be wrong, either qualitivelt or quantitively, but it seems to make more sense than there being no GHE, i.e. the null hypothesis is intuitively more ridiculous, in my opinion.
It's not that we can't "measure the effect nor show it in action" - we can do both right now - it's just that we can't do it in a controlled way, i.e. with proper control, negative testing, repeatability etc which would make it proper empirical measurement worthy of being a scientific 'fact'. We only have the one already extant atmopshere to observe these effects in.
Look at the theory of natural selection in evolution as another 'theory' which can never be stated as fact because of these self-same problems of resources. If we had a few million years and infinite resources, we could 'prove' evolution thorugh natural selection with the same rigour as the charge on the electron or the gravitational constant. But we can't, for practical reasons. Do you doubt evolution because of this? (maybe you do, agw skepticism is a wide church :)
TheBigYinJames
BigYin, this is not cosmology nor evolution. In the first case, there are testable theories, there are falsification criteria. In the second, paleo can be used to show supporting evidence. Indeed the survival of the fittest bit is itself obviousology, I would not dispute it for a minute, but if I were inclined I might suggest it is not the only mechanism involved. But in neither case can I feel the bony hand of somebody groping in my pocket for cash. In CAGW, I can. And it looks like the agenda of change in a certain direction is more important to some than the exactness of 'the science'. They ought to be made to prove it. Or support it with more than dodgy models and half-done atmospheric observations. Right now they fall way short of my tooth fairy proof.
rhoda
Sorry: After the first "this" in my comment above, should be this link:
http://www.nasa.gov/mission_pages/LRO/main/index.html