Proof of the Atmospheric Greenhouse Effect: Arthur Smith
October 10, 2008 By jennifer
Arthurs Smith does not explain the specific contribution of carbon dioxide to global warming, nor does he deal with the issue of convective overturning, but in 'Proof of the Atmospheric Greenhouse Effect' he elegantly explains the greenhouse effect in harmony with "the scientific standards of theoretical physics". In particular he first defines basic terms and relevant equation for energy flow, considers a planet with no infrared-absorbing atmosphere, and then shows that by adding a simple infrared-absorbing layer it is possible to explain why we are not all freezing here on planet earth.
Read more here: http://arxiv.org/abs/0802.4324
Filed Under: Opinion Tagged With: Climate & Climate Change
Smith's paper in full may be read at;
http://arxiv.org/PS_cache/arxiv/pdf/0802/0802.4324v1.pdf
The Gerlich and Tscheuschner, or as a Deltoid regular calls them, those 2 German idiots, paper is here;
For more on the 'greenhouse' dispute here is Smith's critique of Monckton's paper criticising IPCC forcing, or greenhouse, figures, and Monckton's reply to Smith;
http://scienceandpublicpolicy.org/images/stories/
papers/monckton/monckton_rebutted.pdf
ad says
Please don't post cache links. They expire.
Sorry guys; just trying to bring everyone up to speed.
NT says
Is… sorry can't remember his name… The guy who offered $10 000. Is he gonna pay you the money for finding the paper Jen?
NT,
It's a great paper, but doesn't deal with the key issue of anthropogenic carbon dioxide.
You need to try and tease appart the different issues. 🙂
That's a shame… You could have invested that money on the stock market … 🙂
DHMO says
Cohenite in the last quadrant there is an article by William Kininmonth in which he states that rising sea temperature means more evaporation 6% per degree which means less drought. So he is saying that if the oceans around Australian were to warm then we would have less drought. To me if he is right the logical conclusion is that the ocean around Australia is cooling. Do you have any comment on this?
gavin says
Ahhh at last, a great intro for Mrs. C.
At first glance A Smith's neat presentation reminds me of a math tutor's class work at RMIT. His step by step approach to greenhouse critics completely floors fringe science in the most aloof way i.e. through the standard treatments.
Jeff Id says
I had no idea anyone disputed the greenhouse effect.
I thought the only argument had to do with rising CO2 levels creating dramatic increases in greenhouse effect.
gavin; Smith's neat presentation is nothing of the sort, But first in reply to DHMO; I haven't read Kininmonth's piece, but my ininital reaction to the concept that rising SST leads to wetter conditions would be qualified for several reasons, and it may be helpful to look at the BoM data for rainfall totals and anomalies;
http://www.bom.gov.au/cgi-bin/silo/reg/cli_chg/timeseries.cgi
SST is largely determined by upwellings and meridional overturning; these in turn can latitudinally shift evaporative and rain bands; increased evaporation may mean more rain at sea, or as the BoM data shows, different parts of the land; this is illustrated with a comparison of the rainfall data with the PDO phase shifts; looking at those, despite a slight increase in Northern rain, it is possible to say that more rain falls during the La Nina periods when upwelling is at its highest than during El Nino periods. Despite concern about the MDB it is hard to discern an AGW effect in terms of decreased rainfall, outside of the PDO oscillations.
Jeff, Cohenite doesn't like the Greenhouse Effect. He likes some sort of "optical density' theory or something.
Besides lending my sea level yardstick to cohenite & co a while back we can try to offer another and this is all about setting your first premise too.
At the well known risk of upsetting Louis again, it requires us starting with the abundance of extra CO2 we've made recently and asking ourselves what mechanism made it into carbon in the first place, what energy input over what time frame, then imagining just how we are going to restore greenhouse equilibrium, perhaps by putting it all back in the same time frame it took us to burn it.
Nature and now clever math both indicate loose carbon is a menace cohenite
Miskolczi showed that failing a variation in an external radiative source the atmosphere of the earth would maintain radiative and thermal equilibrium by variations in radiative indices; for instance as CO2 levels have increased, RH has declined.
G&T do not dispute heat trapping properties of the thermoluminescent gases; they do dispute that the atmosphere acts like a greenhouse which doesn't have mitigating feedbacks.
Smith erroneously incorporates all the fallacious elements of the greenhouse concept; he states;
"Similar to the effective albedo, an effective emissivity and effective radiative temperature can be defined as averages over the planetary surface;" (p2).
This is wrong for a number of reasons; the Essex paper on the fallacy of an average temperature is one reason; as a corrollary, the Pielke paper on the fallacy of standardising SB emission is another; G&T note this at Fig 3 on p 20; the constant o~ in SB is not universal because at each point of space many (disparate) rays are associated; thus at TOA, outgoing radiation will have different energy vectors depending on their surface source; this is consistent with Stewart's Law which says that the emissive power of an object is dependent on its nature, its temperature and the frequency of observation (per Robitaille).
Smith allows nothing for atmospheric pressure;
http:www.geocities.com/atmosco2/atmos.htm?200820 (// excluded)
This pressure, when combined with convective heat transfer can produce a slight cooling effect at the surface contrary to heating through IR absorption, as Chilingar has described.
Well cohenite, you better email him and let him know.
"Smith allows nothing for atmospheric pressure;..This pressure, when combined with convective heat transfer can produce a slight cooling effect at the surface contrary to heating through IR absorption"
I reckon cohenite has missed the point in this whole exercise
gavin; tell me, what is the point?
NT; Monckton already has; what a bun-fight.
Monckton is a… Well, he's his own worst enemy. I would be surprised if many people actually took him seriously. It'd be like Sarah Palin telling your physics was wrong.
Cohenite, I would like to see Heinz Thieme attempt to explain the ice ages…
The reason I suggested emailing him is so that he could explain to you what is wrong with your argument.
NT; I'll be content if either you or gavin do.
Graeme Bird says
"'Proof of the Atmospheric Greenhouse Effect' he elegantly explains the greenhouse effect in harmony with "the scientific standards of theoretical physics".
Scientific STANDARDS?????? of theoretical physics??????
Right there you have the emissions of some upper class twit-wannabe.
What we wanted was EVIDENCE!!!!
What the flying-blind big-breasted dumb-blondes, is THIS-idiot on about?
But what this Arthur… Arthur…. what this commoner name-of-Smith (these Smiths, don't they just breed like "unsafe" rabbits?)
What this member of the upwardly snobbish scumbags is trying to get over on the rest of us is the aristrocratic right to be JUST AS UNSCIENTIFIC, CULT-OF-PERSONALITY-ADDICTED, AND BIGOTED as those Lords of physics are with their grid-locked, and getting nowhere, search for the one best aesthetically pleasing GOSPEL-MODEL.
Smith.
Will you wipe your nose? Will you get some sort of haircut. Go to the toilet for a change or you'll get toxic shock poisoning. Try not to impregnate the mentally handicapped girls if thats not too much of a put-upon on my part…..
… Just clean yourself up you tramp. You look disgusting.
And once you've emptied and refilled the tub for a fourth time and been comprehensively deloused YOU JERK!!!!!!
…..Then it might be time for you to think to yourself that science is about convergent evidence. Its not about big-noting your lazy ass with the priesthood.
Jennifer: Speaking of Standards, I reckon Graeme Bird should be banned as a simple waste of space.
Louis Hissink says
Gavin: "At the well known risk of upsetting Louis again, "
Quite right – I get a tad upset when such nonsense as this is written "it requires us starting with the abundance of extra CO2 we've made recently and asking ourselves what mechanism made it into carbon in the first place, what energy input over what time frame, then imagining just how we are going to restore greenhouse equilibrium, perhaps by putting it all back in the same time frame it took us to burn it."
Anyone who writes what mechanism turned CO2 into Carbon in the first place is in serious need of counselling.
Greenouse equilibrium – writing this crap Gavin suggests that you are again playing the devil's advocate because no one could be that stupid to write this nonsense.
I could be wrong though. Have been before.
Well gavin. What are you saying here? Are you contesting me on something? Are you in fact claiming that this Smith is not an unscience uppity wannabe faux aristrocratic TWIT?
What was his conceptual argument? What was his evidence?
The jerk was just trying to bluster is through.
We need a bit more biff in the science world. A bit more offense taken and given and a little bit more of the step outside you rascal.
Cohenite; go back to the last para before Smith's Conclusion V after skimming through it all and see if you can't get it before laboriously checking every equation again. I suggest you do the latter with help anyway because I'm certain Smith has cunningly cut it down in anticipation knowing its all been tested before.
BTW it's four decades since I did a load of physics and associated math so I'm relying on sharper minds to take it further. A blanket with different properties depending on your approach side is the clue.
After reading Jeff's article on flaws in the hockey stick and reconstructed NH data I was moved to look again at other critics and targets. I consider this short review of instrument data much more useful
http://atmoz.org/blog/2008/09/08/instrument-error-in-the-global-mean-temperature-anomaly/
White noise, red noise is all fudge to.
"Cohenite; go back to the last para before Smith's Conclusion V after skimming through it all and see if you can't get it before laboriously checking every equation again. "
Dumbass.
Rightful certitude isn't about deductive or mathematical exactitude. He could check all the figures twice and sort out the naughty from the nice and it wouldn't mean a thing.
Rightful certitude is about CONVERGENCE. As one well-known philosopher explains over here:
http://graemebird.wordpress.com/2006/05/03/deductive-bivalent-exactitude-versus-rightful-certitude/
Bird for a bloke who only got 182 votes you're such a noisy wind bag. Toddle off now and turn yourself in.
Yes, gavin, he refers to pressure, then dismisses it in the last sentence, indicating that he relies on IR absorption; as I have said before in relation to the enhanced greenhouse, as defined at FAQ 3.1 at AR4, it is an erroneous theory that the presence of IR absorbing gases, with a constant external radiative source, can, with an increase in those gases, cause an increase in temp to the extent predicted by AGW.
SJT says
One day he might realise why he only got 182 votes.
Don't forget, this paper by Smith was meant to be a very simple rebuttal to G&T and their claims about a non existant Greenhouse Effect.
For a more in depth explanation of the science, Pierrehumberts online text book is excellent.
http://geosci.uchicago.edu/~rtp1/ClimateBook/ClimateVol1.pdf
NT; the comment about the Thieme piece and ice ages is a fair question; if atmospheric pressure is the sole determinant of atmospheric temperature then insolation variation would not have as big effect; Thieme does address this at pp11-13; it also occurs to me that the Earth is not a sphere but is proportionally wider at the equator with more atmosphere then at the poles, with consequent affect on temp; in any event, it is clear that the atmospheric pressure does contribute to temperature of the atmosphere while there is also a contribution from GHG's, particularly water; that contribution is best described by Miskolci's model and not the Weartian AGW one; accordingly, the enhanced greenhouse is not feasible as described by FAQ 3.1.
Cohenite
The earth's oblateness is closer to a perfect sphere than a standard billiard ball.
But then when in the company of fleas on the end of an elephant's tail, minor variations of surface topology might seem signficant. Mathematically that is since temperature anomalies are generally discerned from fluctuations within a 1 K range.
Cohenite the atmosphere is thicker at the equator, I thought… Maybe check that.
I have started reading about relative humidity. Yeah very interesting. Not sure it'll do what you want it to though.
This is an interesting idea and I might look down this path… http://www.springerlink.com/content/vj7653284174618g/?p=2693fdeb08e545059840439d7a4de49f&pi=1
http://atmoz.org/blog/2008/05/07/using-surface-heat-content-to-assess-global-warming/
And this was interestng, just from a historical perspective… Maybe it will give you an idea of the geological side of the Greenhouse Effect
http://geosci.uchicago.edu/~archer/JournalClub/walker.1981.WHAK.pdf
Jan Pompe says
cohenite: "Smith erroneously incorporates all the fallacious elements of the greenhouse concept; he states;"
Take a look at equation 10 there is an effective emissivity {epsilon}_eff that mysteriously disappears when he rearranges 10 to get 12. This sets it equal to 1 effectively.
we also have just following eq 10
"planet On average,
however, over time, this rate of energy change should come very close to zero as long as all the input parameters are
reasonable stable over the long term. If it didn't average to zero for a long period of time, the energy of the planet
would cumulatively build or decline."
Unchanging temperature i.e. thermal equilibrium and Kirchoff's law says that for an object in thermal equilibrium the emissivity is equal to absorptivity. In his paper he has absorptivity = (1-albedo) ~ .7 which is NOT equal to the emissivity set to 1 by default. The paper is a mess.
Jan: ~0.7 = 1 ? It does in Virtual climate world.
Whoops – I forgot to mention the rounding off problem – if we round off to the nearest integer, 0.7 = 1 becomes 1=1.
Is this called climate statistics, or is it the RE statistic. Gasp, could it be geostatistics.
Thanks Louis I enjoyed that.
They have another equality problem:
Oxidise CH4 and it is CH4 + 2O2 = CO2 + 2H2O, (otherwise known as a wet fart).
However, in Virtual Climate World we have
CH4 + 2O2 = CO2
The 2H2O needs to be transformed into a temperature quantum on order for the burning of natural gas to produce CO2 and heat which causes the oceans to expand thermally and thus drown the world's coastlines.
The problem is converting 2H2O into Heat but I have a paper in preparation which will explain this.
The preamble to this post is:
I would have thought that the standards of practical physics would have been more important than its theoretical aspects.
But then I am a mere geologist (engineer).
Louis; "I would have thought that the standards of practical physics would have been more important than its theoretical aspects."
Who was it that said physics has been hijacked by mathematicians? I read it somewhere.
David Hilbert tried got short shrift from Max Planck
http://www.mzwtg.mwn.de/arbeitspapiere/Schirrmacher_2001_1.pdf
It used to be that the theoretical physics followed on from experiment and observation in order to obtain a *useful* mathematical representation of the observation in order to be able to make predictions about how things will behave (where the cannonball will fall) all useful stuff. No more it seems. Mathematical formulations that can by pass the laws of physics area turned into computer algorithms that make scenario projections but never predictions.
Gary Gulrud says
Thanks, Jen, for letting us see this pillar of light.
He goes wrong at the top of the second page. T sub eff, balderdash.
Disappears? It is quite clearly still there. It didn't disappear.
SJT: "but Arctic ice melting, known to be a potent feedback amplifier of CO2-driven warming"
You are right my apologies it disappears in 14 & 15 where he does the integral.
SJT the point is that taking such a purely radiative calculation without taking Kirchoff's law into account you get nonsensical results. It really only makes sense doing such a calculation as seen from space where the you take the same TOA (virtual) surface where incoming = out going for a constant temperature and Kirchoff's law must apply so that emissivity = (1-albedo). If you do that the effective BB temperature = grey body temperature ~ 279K != 255K
An excellent example of the flight into mathematical madness is the idea of a back hole – the reificiation of the mathematical term naked singularity – an infinitely dense point.
While these don't exist physically I am prepared to accept that the astronomers might have got the 3D positioning wrong – there is strong evidence that there are many naked singularities between the ears of the AGW crowd.
Louis: "the reification of the mathematical term naked singularity – an infinitely dense point."
you just need to accept that where there is a black hole is where God showed the human race that He alone can divide by zero and get away with.
More to the point over at CA BB Arthur Smith (author of this topic) has made his weekly appearance, yes we can and do generally keep it civil there. He has just made the assertion that since without GHGs the atmosphere cannot radiate to space and
" That generally suppresses convection – at least vertically, though you would still have tropic – to – pole temperatures driving winds."
But where can these winds go to without concomitant vertical circulation into a black hole and accumulate there so they must exist at the poles or the tropics I just can't get my head around it. The winds just can't circulate horizontally because that would be akin to a heat engine drawing heat from a reservoir an returning it to the same reservoir, and that it can't do with creating that other paradox – a perpetuum mobile of the second kind.
Now Arthur isn't stupid he has done some solid work in solid state physics (no pun) but something strange happens when he gets into climate.
i particularly like this comment by anna v (a CERN physicist) at Watts up with that:
"I will state once more: radiation is not conserved, energy is conserved. Energy is not a vector, as the word "forcing" falsely implies. Transforming thermodynamic quantities from heat and energy into radiation epicycles is something that still boggles my physicist mind. A whole branch of physics, thermodynamics, has been developed to study heat transfers and energy transfers and it works extremely well from delicate engines to huge factories. No forcings in there."
http://wattsupwiththat.com/2008/10/08/dr-roy-spencer-evaporates-taminos-critique
Scroll towards the end (or use search)
The problem with the energy source for the atmosphere circulation is that it's limited to solar radiation – the standard model which everyone assumes needs no further elucidation.
Since the beginning of the space age and our consequent ability to measure in situ close to the earth, has led to the discovery that the earth receives an enormous amount energy in the form of electric currents via the magnetic flux tubes from the sun and presumably other sources which we know very little about.
The intriguing thing is the development of atmosphere LOW systems that sometimes develop into hurricanes/cyclones of predigious destructive power. The enrgy for these is simply limited to radiation from the sun?????
Since electricty is known to be associated with these hurricanes, generally assumed to be created from the vortex motion, it might be better to invert the relationship and suggest that its the increase in electrical energy via the twisting Birkeland currents that supply the energy to power the hurricanes. These things have electric fields some 10,000 + volts measured over them.
But because we can't see electric currents operating dark plasma mode, the must therefore not exist. Hence the emphasis on purely mechanical explanations for weather with the problems you note in your comments.
After all, raising the temperature of water on a stove does produce turbulent motion but no amount of observation or experimenting will cause the formation of vortices in such a turbulent medium – something else has to be added.
Louis; I'd be interested in that paper when it's done.
NT; let's look at the Atmoz effort on enthalpy; enthalpy is the thermodynamic potential of a system; he is right to the extent that evaporated water carries with it latent heat as a product of the energy used to evaporate it at the surface; but he double-dips; when water evaporates there is an energy loss at the surface; there is also no measureable heat gain in the atmosphere since only sensible heat is measured; so far Kirchhoff and Stewart's Laws are maintained; the problem now is a confusion between specific humidity and relative humidity; sh is the actual water content of a body of air; rh is the potential water content of a body of air which increases as the temp of the air does; there has been no tropospheric warming, no hot spot, but rh is falling;
http:members.shaw.ca/sch25/FOS/GlobalRelativeHumidity.jpg (// excluded)
The Minschwaner and Dessler paper also addresses this fact. They conclude that rh is declining because there has been a slight increase in temp and therefore an increase in the potential of the atmosphere to hold water, ie rh. But if temp is not increasing and rh is falling then sh must be falling as well; the only way that could happen is an increase in rain; rainfall has been increasing in Australia subject to variations in where it is falling as my reply to DHMO above indicated; with less water in the atmosphere but more CO2 Kirchhoff and Stewart are still satisfied.
Louis: "After all, raising the temperature of water on a stove does produce turbulent motion but no amount of observation or experimenting will cause the formation of vortices in such a turbulent medium – something else has to be added."
Don't look at a pan of boiling water that randomises the particle momenta look instead at water going down a plug hole.
Ah, the oceanic plugholes into which the cyclones/hurricanes disappear into – good grief they could be black holes!
It was actually tongue in cheek – this was Sydney Chapman's ploy whenever Aflven presented a new paper – it's the academic putdown of interlopers, oh nice idea but we have already solved that and a paper is in preparation type of putdown.
Noted; Atmoz at one of NT's links obviously thinks he has a solution.
Louis,
So who needs a Large Hadron Collider I can use my kitchen sink.
Hmm, this would suggest the existence of Higgs Bisons in such locations, bosons being found Out there, while bIsons in here.
Cohenite,
Atmoz? After Roy Spencer's dismissal of Tamino I would suspect any of NT's references might have similar issues. Jeff Id and Steve McIntyre have put the Hockey Stick finally to rest, though knowing the resilience of these people, the battle is far from won.
Perhaps the self-inflicted economic crisis the AGW crowd have created might dampen their ardor a little.
I did like his 1981 geologhy reference to the GH effect in the Archaean, or lack of. A total lack of observational and empirical data but an excess of geological myths.
"The black holes of nature are the most perfect macroscopic objects there are in the universe: the only elements in their construction are our concepts of space and time." Subrahmanyan Chandrasekhar
At least your gravatar now has the correct idiotic persona. Dad's army at full intellectual thrust.
If the water content of air (the specific humidity) remained the same and the temp went up, the RH would decrease.
http:en.wikipedia.org/wiki/Relative_humidity
They have a diagram down the page:
http:upload.wikimedia.org/wikipedia/en/7/7f/Changes_in_Relative_Humidity.png
This is a first pass at what was easy to find. But we can start to see where the discussion will go. It seems to be a question of where RH is decreasing faster than it should for a increase in temp. Would you agree?
This relates directly to SH (the actual water content of air). I think I saw some graphs that showed SH was declining until the 90's, but then started to climb again.
You keep saying there is no hotspot, but the systems we would need to detect one may be inadequate.
I might be able to comment on your atmospheric density comment soon… It may be that density is a factor for greenhouse gases. So if a gas is transparent to IR (Such as O2 and N2) it doesn't matter how dense you make them (or at least it doesn't at Earth type pressures) they still won't absorb IR, as they are transparent.
How thick do you have to make glass before it becomes opaque?
As to Atmoz double-dipping, not sure why you think there is anything amiss. Can you explain it in a different way?
Luke B.Sc. (Hons) :"You keep saying there is no hotspot, but the systems we would need to detect one may be inadequate."
Oh, so despite the fact we have not observed a signature hotspot, we actually might have if the systems to detect it were up to the job.
How about lack of hotspot due to the theory being inadequate.
Louis, meet NT.
An increase in sh will not cause a temp increase in the atmosphere because the moisture is rained out or subject to -ve feedbacks through cloud formation; the decline in rh, even if there is an increase in sh, is consistent with Miskolczi, because the increase in CO2 maintains a radiative equilibrium between the surface and the CEL. N2 and O2 absorption of IR is related to atmospheric pressure in the sense that the greater the depth of the atmosphere the more chance of the optical depths of the 2 gases being correlated with IR in the available wavelengths; at the current depth/pressure of the atmosphere about 10% of the emitted IR photons are absorbed by N2 and O2; the optical depth of CO2 is about 10 metres by comparison and water less again; if there was no convective adiabatic exchange plants would be smaller and thunderstorms would be at your ankles.
Gordon Robertson says
Smith's paper is a response to the paper by Gerlich and Tscheuschner and he has cherry-picked one part of their paper while ignoring the rest. I found his paper to be rather pompous in that it did not address the points made by G&T but merely reiterated the stock paradigm.
G&T infered no explanation of the greenhouse effect could be found in physics papers. They went to a lot of trouble to explain how a real greenhouse works and how the atmosphere is nothing like that process. In fact, they pretty well destroyed the pseudo-science upon which AGW theory is based and the obvious flaws in climate science as practised by many of the latter.
As far as I'm concerned, it is G&T's paper that we should be discussing here and not the nuisance crap offered by Smith.
So you understand that RH decreases with increasing temp?
Not sure why you are talking about raining out SH… It's RH that determines whether or not there is rain. And cloud formation is determined by a lot of different factors.
I'll have to check this: "N2 and O2 absorption of IR is related to atmospheric pressure in the sense that the greater the depth of the atmosphere the more chance of the optical depths of the 2 gases being correlated with IR in the available wavelengths; at the current depth/pressure of the atmosphere about 10% of the emitted IR photons are absorbed by N2 and O2"
As far as I knew O2 and N2 were transparent to IR.
Lets not leap ahead to convective transfer yet…
Gordon, why would G&T talk about real greenhouses? the greenhouse effect has as much to do with greenhouses as car parks have to do with parks.
this statement "at the current depth/pressure of the atmosphere about 10% of the emitted IR photons are absorbed by N2 and O2;"
Which photons are you describing? The ones emitted from the surface?
Cohenite thanks for the link, I have had a fair look at it but it doesn't help much. There is a lot of interesting data there though. Louis my usual question is could someone show me a black hole. Not a picture but a real one! I recognise your gravatar he was very good at what he did. Are your sure you should be using him? I have found a webcam that views the LHC you guys might be interested. http://www.cyriak.co.uk/lhc/lhc-webcams.html
"RH decreases with increasing temperature" ? Rh is a ratio of the actual amount of water vapour in the air (sh) to the amount it could hold when saturated; the amount of water vapour the air can hold INCREASES with temperature; therefore rh decreases with increasing temperature if the actual amount of water vapour (sh) stays the same; some scenarios;
If the air temp is increasing at a faster rate than sh then rh is declining;
If temp is increasing but sh is constant then rh is declining;
If temp is decreasing but sh is declining at a faster rate then rh is declining; and so on and so forth.
DHMO; have a look at these Frank's papers discussing ENSO and rainfall variability, especially in Eastern Australia;
http://www.agu.org/pubs/crossref/2005/2004WR003845.shtml
http://www3.interscience.wiley.com/journal/108562474/abstract
Cohenite, ok so we agree on RH. If you keep SH the same, and raise the temp RH drops.
Now rain happens when the air temp changes and raises the RH. I don't believe water will keep evaporating (thus raising SH) if it will exceed 100% RH. It needs a change in temp, yes?
And you can have a very high RH and/or SH without clouds, yes?
O2 and N2, where did you get your value of 10% from. I can find a few spectra for O2 in the IR emission range, but none for N2. The O2 absorption spectra are very narrow, how could it represent anywhere near 10%? And don't you ascribe to the saturation argument? Wouldn't that O2 absorption band be saturated already?
Black holes have no physical existence – by definition they are unobservable, hence by definition imaginary – existing in the imaginations of the scientifically confused who have ended up in the cul de sac of mathematical virtual reality where thought experiments are the only ones they do.
Actually I wanted to use Warner Brother's Foghorn Leghorn as a gravatar but that's been taken up here by someone else.
I was advised to look in this online book: http://geosci.uchicago.edu/~rtp1/ClimateBook/ClimateVol1.pdf
And here it explains why N2 O2 and H2 don't contribute to Earth's Greenhouse Effect.
"Many common atmospheric molecules have no dipole moment in their unperturbed equilibrium
state. Such nonpolar molecules can nonetheless couple strongly to the electromagnetic field.
They do so because vibration and rotation can lead to a dipole moment through distortion of the
equilibrium positions of the electron cloud and the nucleii. As illustrated in Figure 4.9, diatomic
molecules made of two identical atoms, do not acquire a dipole moment under the action of either
rotation or stretching. Symmetric diatomic molecules, such as N2, O2 and H2 in fact have plenty
of rotational and vibrational transitions that are in the infrared range. Because the associated
molecular distortions have no dipole moment, however, these gases are essentially transparent to
infrared unless they are strongly perturbed by frequent collisions. This is why the most common
gases in Earth's atmosphere – N2 and O2 – do not contribute to Earth's greenhouse effect.
However, it is important to recognize that situations in which diatomic molecules become good
greenhouse gases are in fact quite common in planetary atmospheres. When there are frequent
collisions, such as happen in the high density atmospheres of Titan and on all the giant planets,
diatomic molecules acquire enough of a dipole moment during the time collisions are taking place
that the electromagnetic field can indeed interact with their transitions quite strongly. This makes
N2 and H2 the most important greenhouse gases on Titan, and H2 a very important greenhouse
gas on all the gas giant planets. In terms of volume of atmosphere affected, Hydrogen is by far the
most important greenhouse gas in the entire Solar System. Collision-induced absorption of this
type forms a continuum in which the absorption is a very smooth function of wavenumber, without
any significant line structure. Polyatomic molecules can also have significant continua, existing
alongside the line spectra. Continuum absorption will be discussed in Section 4.4.8."
2 Sources are;
http://cat.inist.fr/?aModele=affichneN&psidt=5123851
http://www.iop.org/EJ/abstract/0022-3700/10/3/018
"A very high rh and/or sh without clouds"
Not for very long I would suggest; the inversion necessary to ceiling the saturated air would fracture horizontally because of the pressure differences.
That 1st link is here;
http://cat.inist.fr/?aModele=affichneN&cpsidt=5123851
Yes, it it is a process which increases as density increases.
Sorry, I'm having trouble with that link. The point is N2 absorbs IR via quadrupole absorption.
Actually Cohenite, ignore my above post, it'll just confuse our discussion. Maybe we can come back to it later?
But you could still have a high SH and no clouds, or maybe SOME clouds.
Ok, so we have rain is a product of RH, not SH. And we have the idea that increasing SH does not necessarily result in more clouds, but would if there was a sufficient increase and other factors favoured cloud formation. So an increase in SH wouldn't necessarily result in a corresponding increase in cloud cover
So, you CAN get an increase in SH without rain and without necessarily increasing cloud cover. Which means that additional water could act to enhance the greenhouse effect.
That second link talks about collisions.
http://prola.aps.org/abstract/PR/v75/i10/p1607_1
That might be the one you;re after…
What is quadrupole absorption?
The quote from Pierrehumbert's text are not based on in situ measurements, aside from the fact that it is a jumble of pseudoscientific gobbledygook.
Cohenite; I'm surprised you are still on about Franks. Adaptive management put simply, learn and adjust as you go
http://search.informit.com.au/search;action=doSearch;search=subject%3D%22Predictive%20control%20–%20Mathematics.%22
http://en.wikipedia.org/wiki/Adaptive_management.
Gordon; Smith's stuff looked pretty straight forward to me. It's an old mathematical procedure in regard to orbital bodies and their climates. Physics = math = physics and I expected Jan to follow it step by step as presented.
Transparent, opaque and semi transparent atmospheres were a good enough outline without bothering about the pressure differential top to bottom. Nit picking, we could get hung up too in where the various GHG's and vapors were most effective in their transmissions one way or another but the thing to remember is radiation at SL is not necessarily the same as radiation at the outer fringe.
NT; the Rastogi paper discusses quadrupole absorption, as they call it the quadrupole moment; as I understand it GHG's absorb via a diapole moment; diatomic molecules don't have a diapole moment; however, under sufficient pressure (satisfying optical depth) an asymmetrical charge distribution will provide a net daipole moment; the asymmetrical charge distribution is quadrupole in nature. We are only talking about a fraction of radiative absorption with O2 and N2; a potentially more important source or method of atmospheric heating and transfer is the conductive heating of the atmospheric mass through contact with the surface.
the various mechanisms invoked for quadruple absorption are not from in situ measurements but from beliefs of what might occur in the molecular domain.
Don't get distracted by specious arguments.
Tim Curtin says
Jen: are you available for Vogue?
Meanwhile, what do you make of this from Barry Brook?
"Yes, we are on track for 1000+ ppm – even before carbon cycle feedbacks (permafrost melt, declining/collapsing oceanic and terrestrial sinks) kick-in, which were only marginally considered in those IPCC A1FI scenarios. But really, by the time we've crossed 750ppm, there's no chance for our society, so the planet can have a carbon party after that and humanity won't be around in a civilised form to give a rat's. The 300-400ppm range is sufficient to trigger major adaptation challenges and costs, and the 450-650ppm range is enough to push us to or beyond the limits of adaptation".
We were at c300 around 1950 without so far as I know becoming extinct and have already reached 455 CO2-e (but perhaps we are all only virtual now). Is Brook a real person or just a fiction from the latest Playstation?
John F. Pittman says
Tim, the message appears to be from the latest playstation. There has been a tendency for the percentage amount of ACO2 that is retained in the atmosphere for each years addition to go down. A simple linearization indicates that it would take over 4000 ppm to get to the 600 ppm range. The total ACO2 introduced would be about 10 times that much. Thus one of the assumptions is that these sinks are going to either be less effective or will "fill up". The models assume this. What is known at present and it is indeed a very short time line, is that as our yearly CO2 has increased, the percent retained by the atmosphere for that year has decreased. And though I agree that a sink cannot take an infinite amout of CO2, it is assumed that the sinks are near saturation. However, what is known of the oceans' buffering capacity for CO2 has not been reached. Nor has it been shown with the ratio of emiited versus retained in atmosphere that the sinks are nearing saturation.
Eli Rabett says
There is a fundamental misunderstanding here. Smith shows that assuming a uniform single level absorbing atmosphere, and uniform surface temperature sets a LOWER limit on the magnitude of the greenhouse effect (the temperature difference of the surface temperature with and without an IR absorbing atmosphere). This is about as simple as it gets. Any more realistic assumptions or complicated many level calculation will yield a LARGER temperature difference between the surface with and without back radiation (the greenhouse effect)
It is obvious that allowing additional heat flow from the surface by convection or whatever without back radiation would make this difference (the greenhouse surface warming effect) even larger because it increases the flow of heat energy AWAY from the surface.
Further G&T falsely claim that the role of radiation in the greenhouse effect violates the second law of thermodynamics. This claim fails because the surface is warmer than the atmosphere, and the second law only refers to net flows of heat.
Oh yeah, Smith also shows how to define an average surface temperature for a planet under all conditions
Cohenite thanks for the links.
Eli Smith makes the simple mistake of doing a purely radiative calculation from two *different* surfaces in coming at TOA where purely radiative effect applies and out going at the surface where you also have convection and latent heat transfers etc. The upshot of this is of course that he has an unchanging temperature i.e. a planet in thermal equilibrium with incoming power = outgoing power with absorptivity = .7 and emissivity = 1 so Stewart's law holds but Kirchoff's does not?
If in fact he calculated absorptivity and emissivity at the same TOA surface he would get an equilibrium temperature of ~279K which is warmer and a lot closer to the "observed" average average of 288. (TIGR profiles a more recent data set has the global average surface temperature at 286.K which is even better)
Yes, I'm afraid eli's comments raise more questions then they answer. Just thinking about Jan's reference to anna v above about energy not being a vector; Kirchhoff and Stewart's Law cover the same territory; Kirchhoff assumes universality but Stewart says the emissive power of an object is dependent on its nature, its temperature, and the frequency of observation ( per Robitaille); emissive power here is the energy contained and carried by the radiation which as a package is a vector; Smith says;
"the variability in infrared emissivity is relatively small across the surface of a realistic planet"
This is the foundation of Smith's, and eli's and AGW's assumption of average temperature and radiative balance; however, as the Pielke paper shows, a proportion of the radiation emitted at the TOA must originate from the surface; the surface has vast disparity in temp and therefore SB emissivity; up to 100C; the energy distribution curve for those disparate SB values are equally disparate at TOA, and indeed, at atmospheric surfaces such as the CEL; as G&T say the AGW radiative balance concept "cannot represent radiation intensities." If there is not an average temp based on a radiative balance there cannot be a uniform greenhouse effect because the back radiation energy varies enormously as well.
Cohenite, you have forgotten about our discussion about RH.
Do you know acknowledge that RH Is an inappropriate measure of whether there is an increasing amount of water in the atmosphere?
And where did you get 10% for N2 and O2?
10% for N2 and O2; ask eli.
As to rh being an inappropriate measure of whether there is an increasing amount of water in the atmosphere, that is a non-sequitur; because rh is the measure of the latent heat capacity of the atmosphere, if that is dropping then even if CO2 is heating the atmosphere as per eli and Smith and AGW, there is a major compensatory process similtaneously occuring; enhanced greenhouse depends on rh either remaining static, which if sh is increasing, means rh is actually increasing, or increasing regardless of what sh is doing; remember rh is a response to increasing air temp, as per my scenarios above; so, saying water levels may or may not be increasing in the atmosphere and ignoring rh is misleading.
Cohenite, what is the SH of the atmosphere doing?
"enhanced greenhouse depends on rh either remaining static, which if sh is increasing, means rh is actually increasing, or increasing regardless of what sh is doing;"
I don't understand this, why does it depend on it?
Can you not imagine a system where SH is increasing, temp is increasing, but RH is decreasing?
gavin "Gordon; Smith's stuff looked pretty straight forward to me".
Have you looked at Gerlich and Tscheuschner? They systematically destroy the entire greenhouse paradigm as well as the AGW theory, using basic physics to do it. They are both theoretical physicists.
I have yet to see a convincing arguement against what they are claiming. Smith failed to address the deeper issues in G&T, prefering to spout the peculiar orthodox theory of climate science.
I personally don't think climate science is based on robust physics. It seems a bunch of renegade scientists pushed their own brand of physics and I don't think many of them were good at physics to begin with.
Climate science is a sub-science of meteorology, geophysics, etc. It's not a mainstream physics discipline and many of it's paradigms, like the greenhouse effect, is not considered part of physics, according to G&T. As Louis has pointed out with regard to disciplines like astronomy, they tend to take licence with basic physics. Meteorology is sound in itself when they stick to atmospheric phenomena they understand, but when they start fiddling with the Laws of Thermodynamics, they misinterpret the fundamentals, as G&T point out.
NT "And here it explains why N2 O2 and H2 don't contribute to Earth's Greenhouse Effect".
They do play their roles in preventing heat loss according to Stephen Wilde. He thinks it's the density of gases in the atmosphere that delay the release of heating from the Sun rather than the Greenhouse Effect. That makes good sense to me since photons trying to escape play a massive game of pinball, colliding with all sorts of atoms.
http://co2sceptics.com/news.php?id=1562
Louis "…Foghorn Leghorn.
Were you goin' on about…Ah said…we're you talkin' about Foghorn Leghorn? I think he's out courtin' the Widda Hen.
Gordon, the photons will only be absorbed ('collide') if the atom is capable of absorbing photons of that particular frequency. Maybe you can read up on what it means to be transparent. Some gases are transparent at different frequencies.
Sometimes I get too diplomatic – 🙂
Unfortunately Gavin, and the rest of the AGW supporters, don't seem to understand the crucial difference between purely deductive reasoning from assumptions deemed true by consensus, and deductive reasoning from empirically verified physical facts.
I have the impression that no amount of evidence could sway AGW believers since they base their whole position on a consensus.
NT re your earlier quote on atmospheric gases from the University of Chicago. Nothing personal against you, but please be advised that the author of the book is Pierrehumbert, a guy with rather extreme views on global warming. He's a regular contributor to RC and I find him more of a zealot than a reliable source.
NT "Gordon, why would G&T talk about real greenhouses? the greenhouse effect has as much to do with greenhouses as car parks have to do with parks".
That's the whole point. There is an inference that GHG's are trapping heat by acting like a large blanket around the Earth. G&T are questioning the entire AGW theory using basic physics. They started with the greenhouse paradigm to show it has no place in physics and they describe a real greenhouse to show why.
The real greenhouse has a definite boundary region (the glass), and climate theory suggests the atmosphere operates in a similar way, which it does not. The heat built up in a greenhouse is not due to the glass trapping IR, it is due to a lack of ventilation. There goes any similarity between our atmosphere and a greenhouse.
G&T are questioning the calculations of greenhouse warming using the simulation of an Earth with no atmosphere vs. the Earth with an atmosphere. They ask what happened to the simulation of an Earth with no oceans vs an Earth with oceans. The fact is that greenhouse warming is a mathematical calculation based on a shaky foundation. The theory seems reasonable till you see what it is based on.
It's not an inference, it's an explicitly used as an analogy to explain a complex piece of science to the general public. As an analogy, it's not bad, because the heat is not 'trapped', it's transmission is slowed, effectively warming what's inside the blanket, or greenhouse gas. Just like every year we teach high school students that atoms a little balls, when they quite clearly aren't.
WJP says
Foghorn Leghorn is one of the C 20th great philosopers. Period.
"Two half nothins is a WHOLE nothin!!"
You do him a great disservice. A zealot is a mindless follower of a cause, Pierrehumbert is a noted scientist, with a free book online about the climate.
Could you direct me to the zealous parts of it please?
http://geosci.uchicago.edu/~rtp1/ClimateBook/ClimateBook.html
"Gordon, the photons will only be absorbed ('collide') if the atom is capable of absorbing photons of that particular frequency. Maybe you can read up on what it means to be transparent. Some gases are transparent at different frequencies."
He won't do that. If he has to understand it, he'll have to change his mind.
What is interesting is the 'trapdoor' effect. Short wave radiation coming in, passes easily through the trapdoor, long wave radiation coming back, is stopped by the trapdoor.
PLEASE NOTE! Just a simple analogy, not to be taken literally, but roughly describes how the GHG effect works.
Ah, then that makes SJT the zealot.
NT; deja vu; rh is a measure of the water in the atmosphere expressed as a ratio of the actual vapour pressure (sh) to the saturation vapour pressure expressed as a %; you know when the funny man on the news says humidity is such and such he is talking about rh; if you cool air while maintaining constant sh you will achieve dew-point saturation; in this instance rh is high/maximum because temps have dropped; if the atmosphere is warming but sh is constant the rh ratio falls because the warming increases the capacity of the air to hold more water; and you will need more water to reach saturation and precipitation; but warm air cools and the dew-point response occurs.
If we assume that the extra CO2 in the air is causing warming through will's absurd trapdoor analogy, that extra energy heating the surface will be used to evaporate water; because water has a relatively high specific heat the extra energy will be used in heating the water, not the surface; the temperature at the surface will drop because the heat used to evaporate is carried with the water vapour as latent heat; the water laden air (higher sh) will, given that the tropopause temp is fixed, lower the lapse rate and cool the surface further; the vapour in the air will not warm the air because it will rise and condense; the energy will be lost through precipitation and the albedo will increase through cloud formation. Now read this description of the enhanced greenhouse effect from FAQ 3.1 and explain how water can increase temps either at the surface or in the air;
http://www.climateaudit.org/?p=2567
anna v says
Comment from NT
Time October 12, 2008 at 11:33 am
Well, maybe you should also look up the difference between "collide" and "absorb"'
Photons can have elastic collisions that can change their directions completely. There is also the Compton effect where they give up energy ( kinetic on the target) and change frequency. Photons are not so simple, and transparency is not so simple.
Yes, Anna, but Gordon is simple and needs simple explanations.
Cohenite, I think this statement is what had me confused:
"rh is the potential water content of a body of air which increases as the temp of the air does;"
I thought you were saying the rh increases as you increase temp, which is not true.
"that extra energy heating the surface will be used to evaporate water; "
But heating water is not the only thing it can do. It can do other things as well… It can melt ice, for example.
"because water has a relatively high specific heat the extra energy will be used in heating the water, not the surface;"
What if there is no water nearby?
"the vapour in the air will not warm the air because it will rise and condense;"
That's why it's so cool on a humid day… Because the air is not warming nearby surfaces… Hmmmm.
The rest of your comment I won;t answer as we still haven't got sound agreement on what is happening.
I think that warm air will do more than just evaporate water.
Gordon: "That makes good sense to me since photons trying to escape play a massive game of pinball, colliding with all sorts of atoms" I have to ask, do you really know what a photon is?
Going back "Climate science is a sub-science of meteorology, geophysics, etc. It's not a mainstream physics discipline and many of it's paradigms, like the greenhouse effect, is not considered part of physics, according to G&T"
Before and after doing my own studies I worked for a small number of very practical physicists. While doing optics I never bothered with molecules, atoms or other sub atomic particles in the way we did with electronics, vacuum tubes etc. When doing radio waves I carried on thinking in terms of light, line of sight etc except for the very low frequencies. With x rays and beyond I think in terms of plasma and particle beams that can actually do some damage in collisions. Working on laboratory XRF automatic assay equipment and RF furnaces, one has to know exactly how things work or become instant history. Radiation as a term covers all these conditions and is quite different to what we did with heat exchangers at the lower temperatures.
When I say Smith has done us a favour, I mean it from a very practical point of view. Energy mid spectrum is all about emf power in watts, frequency, wave guides and transducers. Compared to the extravagant waffle in T & G (tried to read it before posting) IMO we are much better off with Smith. IF ever I saw a more blatant or biased attack on the development of greenhouse physics I can't recall it; sorry
I think you may need to examine this statement more closely. What makes it condense? And what happens when it does?
NT; in their discussion re heat pumps and lack of appropriate work I couldn't help thinking we do have such pumps in the form of air circulation, evaporation, condensation etc.
BTW Gordon I'm an old steam jet – vacuum pump fan
Warm air won't do anything except rise; we're talking about the transfer of surface moisture to the atmosphere and the effect that moisture has on global heating, if any. My point is that IPCC state quite clearly that the effect of water (primarily) is to enhance the temp effect of a doubling of CO2 from 1.2C to 1.5-4.5C, averaged to 3C; IPCC estimate the forcing effect from water at ~1.8C (read TAR 1.3.1)
What I'm saying to you and any one else who has a 1/2 open mind is that is not happening; rh is falling, here is the evidence; again;
Now, since the atmosphere is not warming as unequivocally predicted by IPCC at AR4 FIG 9.1(c), p675, that must mean the increased sh is having a cooling effect as predicted by Miskolczi. End of story.
I don't get it Gavin.
Cohenite, stop jumping ahead.
"we're talking about the transfer of surface moisture to the atmosphere and the effect that moisture has on global heating, if any."
No, we were discussing what happens to RH and SH when you heat air. We hadn't got as far as you think becuase we can't seem to agree on whether warm will do more than evaporate water.
"Warm air won't do anything except rise;"
It travels sideways too! Ever felt a warm breeze?
yes, I know RH is falling. I acknowledge that.
Did you see my other questions?
What? we can't discuss it?
Is rain ever warm? Have you been rained on in the tropics? It's not cold.
Ah, the tropics; my first overseas sojourn to Tahiti in 1970; now that was warm.
Wow, I wasn't even born!
Well whipper-snapper, you will be pleased to know that the IODP expedition, as far as I can ascertain, found no evidence that sea-level is rising around Tahiti.
I can also add that personal contacts in the RAN know of the scientific study for Tuvalu sea levels and that the scientific report concluded no sea level rise for the period in question. However the Tuvalu government did not like this conclusion and amended it to conclude that sea levels were rising in order to get funds from the World Bank.
The scientist responsible for the report, partner of one of the RAN officers, became most upset over this adjustment of the report. Since then I have had enormous difficulty tryying to get survey data and other geodetic data establishing land surface benchmarks. Relevant reports were inaccessible.
It's political interference like this which destroys any credibility for AGW science. Its equally a pity that the useful idiots are so gullible with the specious IPCC science.
But even more amazing is the ignorance about the credit crisis etc – my people working for me, young men ~ 30 years are totally oblivious of the situation – does not enter into their consciousness – science graduates and all they are interested in is some music thingy in QLD in a couple of weeks time.
Times are good Louis, and the young have never experienced life without the presence of our marvellous civilisation; sometimes I think they think it will keep on like ZPE, despite all the assaults on its structure, AGW being the latest and most fundamental; our good life is built on energy which keeps the ravages of nature at bay; it seems that one may have to experience hard times first-hand to really appreciate what we have; as Wilfred Owen said;
"And I saw white bones in the cinder-shard,
Bones without number.
For many hearts with coal are charred,
And few remember."
Still, I blame my generation, the Whitlamites, who demanded freedom and are yet to discover that everything has a price.
What elitist nonsense cohenite. My forbears survived one, if not two depressions and the nasty downside of capitatim.
BTW I met the old guy again today who produces a variety of tomato seedlings for markets. When I asked for several plants that would do well in full sun he warned me our summers are getting hotter and I should start shading them from the more intense heat
Louis; you too should get along to
Louis; You should get along too
http://www.woodfordfolkfestival.com/main/index.php?apply=&webpage=default&PHPSESSID=&cID=2008&menuID=272
Gavin:"The nasty downside of capitalism ?"
Capitalism doesn't have a nasty downside – you'll find the architects behind the present crisis are your own – the robber barons who use the State to line their wallets.
As for folk festivals – no thanks, life is interesting enough without the distractions of the surreal.
Gavin:
I was in Hassad's Lebanese restaurant in Cooma when Jim Cairns and Morosi and courtiers dined on a weekend evening.
Hence my implacable opposition to socialism in all its forms.
"elitist nonsense"; listen mate, my protein sources for the 1st ten years of my life were rabbits and top-notch pigeons; there were no fall-back positions; I don't know what is so elitist about that, but feel free to regale us all with another of your anecdotes about line of sight measurements and johnny on the spot details to prove your point.
Any Folk festival that is going to invite the Premier of Queensland Peter Beattie can't be taken seriously. I think it comes from constant immersion in Gunga smoke.
The title of this thread is "Proof of the atmospheric greenhouse effect".
One does this in mathematics.
In the physical sciences one tends to publish experimental confirmation of the effect.
This is a little like me modelling a mineral deposit from which by the use of mathematics I can prove, in terms of the starting conditions, that the theory is correct.
This is BS.
"and the young have never experienced life without the presence of our marvellous civilisation;"
Yes, and aren't we so undeserving?
However, we having an interesting discussion about humidity…
Have you decided that a warm atmosphere can do more than evaporate water? Or that it can transport heat in more directions than up?
Cohers, you can email Arthur Smith.
I did and he answered me, he gave me the link to Raypierre's climate ebook.
He may be more grateful for his lunch than I, being older, and would probably do a better job of explaining his work than I could.
His email is easily obtained by Googling "Arthur Smith Physics"
Foghorn Leghorn – hahahahahahaa…. oooo it hurts.
Jim and Junie – man Louis you must be prehistoric – like that's back in the day …
like that's way back in the day … when the morons were in charge?
Johnathan Wilkes says
Jim's handiwork was felt for a very long time indeed, and took some effort to correct it.
As much as I don't like Paul Keating he was the one to finally lay to rest JC's legacy.
Age is relative!!
Louis: There is another side to every story. I once doorknocked Mrs J C and most of her street in the "Heartland". Their combined expectations of the man surprised me but his downfall in Canberra did not. People can change their ways without an obvious reason.Thats something else we learn from experience.
Cohenite; The only point I needed to make here is that Ive done enough physics both ways to know when others are on firm ground with their arguments.Switching off politics during a proof is also essential for lasting impact and it seemed to me that T&G had not derived anything original despite all their bluff. Sorry if I trod on your toes re lifestyle and oreign.
NT; before I was thinking about examples where work may be done other than by radiation. The most simple of course is our evaporative coolers. The circulating fan drives this thing to the point where our room gets damp in the worst case. Water running down the walls is not its best feature. Other than that I spent a long time around industrial processes, including wet ones such as paper making, mineral concentrating, sewage and food stuffs. Dewatering and humidity measurements were a big part of that game as dewpoint becomes a new problem is these environments.
Luke: you OK, truly ??
NT, since luke has resurfaced to display his razor wit I guess what you mean when you talk about heat going in all directions is a reference to Philipona, who luke has communicated with, just as you have communicated with Arthur; keep those e-mails lads, they may be worth something some day.
I may be getting into dewatering Gavin,
HOPEFULLY I'll be getting a new job in the next couple of weeks… Sadly that may mean I won't be able to blog here much anymore.
HOWEVER, it will make me happier and so when I do blog here it'll be a joy for all to behold!
Yes, with regards to work: I was quite confused when Cohenite appeared to declare that the only thing a warmer atmosphere could do with all that energy is evaporate water… Weird.
Come on Cohenite, email him. he's friendly and punctual.
spangled drongo says
"IF ever I saw a more blatant or biased attack on the development of greenhouse physics I can't recall it; sorry"
What're greenhouse physics?
Julian Braggins says
Have you tried pre-cooling the air to the evaporative cooler using the cooled water from the evaporator ? I use that system and get lower than wet bulb temps. in the house, never have condensation problems, making sure of course that there is free ventilation to outdoors. I do live inland though, rarely get high humidity with heat.
Spangled; if you are not having a lend of me up there, I would say the Smith proof stands out in all the stuff posted here under the science banner. Its simple math & physics designed for all from college to whatever. The other is typically beating round the bush. Example – The criteria in T & G – Falsification (K) "Be tentative" IMO is hardly the way to grapple with global warming. believe it or not and of course from a strictly engineering point of view. In quantity surveying for a plant upgrade I expected a 20% contingency budget on the automation side. Lets note though I was dissapointed often enough to groan at the thought of another project run by some external consultants with their accountants to the fore and perhaps that's where we differ too.
NT; hint?
What warmer atmosphere? NT you've been sleeping with a copy of Sherwood and Allen under your pillow again;
http://wattsupwiththat.files.wordpress.com/2008/08/hadat2_june2008.png
Julian: seems you are into some tricky engineering but let's go back to basics where a housewife may have used a towel dangling in a tub of water and a simple fan to circulate air round her exhausted enfant's crib. How do we improve on that? btw Ive been up since 4 am so any thinking has slowed right down
But let's not Jinx it.
I'm superstitious.
And an AGW Zealot
Cohenite, I looked at the Hadley Centre and their graphs look different to Anthony Watts… Weird.
try this;
http://climateresearchnews.com/wp-content/uploads/2008/10/uah_lt_since_19792.jpg
Or these;
http://rankexploits.com/musings/wp-content/uploads/2008/08/falsifythroughjuly.jpg
Yeah, it's fine Cohenite.
I guess it depends on your time scale.
The Hadley Centre graphs must use some data processing or something. They seem to show strong Stratospheric cooling, but pretty ambiguous Tropospheric data.
We'll just have to agree to disagree 🙂
As usual…
gavin "I have to ask, do you really know what a photon is"?
I would have to say no, and neither does anyone else. It comes from that nether-science called quantum mechanics, and funny-enough involves Planck's quanta.
I'm geting a bit fed up with phenomena that is classified as both a particle and a wave. That could only happen in the jargon of mathematics. Why don't they just admit they don't know what is going on? When I studied physics, we did experiments involving diffraction gratings. In those days, it was waves that were diffracted through a slit, converging on a target so as to cancel out or enhance other waves falling there. Now they are talking about single electrons being shot at a slit and diffracting in the same way.
When an electron beam is shot from a heated cathode at a television screen, it has to be shaped by a powerful magnetic field to focus it into a beam. Otherwise, it will presumably scatter into a wave-like emission. That makes sense since emissions from a hot cathode would not form into a focussed beam. How is it they get so-called individual electrons to focus on a slit in recent experiments on diffraction, then imply they behave like a wave? Sounds like cobblers.
I'm really losing my confidence in science. Quantum mechanics is based in mathematics, namely probability and statistics. Newtonian mechanics gave us a really good basis for physics, especially when Maxwell unified much of it with his equations. Then came the nutters like Heisenberg, who pulled an equation out of nowhere and applied it to Newtonian principles. He fluked a response and now that crowd is running around claiming Newtonian physics no longer applies. We should clue in when a physicist of Feynman's eminence tells us that QM works but that he doesn't know why.
I have already offered my opinion, it was a fluke based on a mathematical relationship. Now we talk about quanta and photons as if they are real entities, yet no one has ever witnessed them. When I refer to photons, I am refering to measurable IR energy emitted from a body into space. I really don't care what happens to it, I am only pointing out that it is met with a barrier of gas molecules through which it must maneuvre.
I'll tell you something else. I don't think climate scientists have a clue what is going on either. G&T are genuine physicists who study the underlying science directly. They are trying to tell us that the physics of climate science makes no sense. I have read through the paper several times, albeit with my limited understanding on in-depth physics and math, and I think the onus is on the climate community to disprove what G&T are saying, not the other way around.
Climate science is a subset of physics and as such must follow the well-established laws of physics. As G&T point out, the climate crowd have screwed up the laws of thermodynamics.
Gordon; you are correct; there is a lot of anti-science in AGW; the G&T and Smith gefuffle exemplifies this; Smith is all assumptions and analogies and wishful thinking; G&T seem very hard-nosed; the conclusion at 2.1.5 typifies this, and should be read in conjunction with the Robitaille paper on Kirchhoff and Stewart's Laws, the Pielke paper on Stefan-Boltzman and Miskolczi; AGW is about simplification and G&T show the real world is more complex and less manageable than an assumed and desired pseudo-reality. I think the false debate about science should end and the issue should be the psychology of those advocating AGW; Heisenberg would be at home there.
WJP "Foghorn Leghorn is one of the C 20th great philosopers. Period.
Also.."Your built too close to the ground , boy, it went way over your head".
and…"Nice girl, but about as sharp as a sack of wet mice".
SJT "It's not an inference, it's an explicitly used as an analogy to explain a complex piece of science to the general public…".
The inference is still there that GHG's trap heat. CO2 is an extremely rare gas, and water vapour, the supposed driver of the greenhouse effect, accounts for only 1% of atmospheric gases. Exactly how do two gases, accounting for only 1% of the atmosphere, trap enough heat to raise the temperature of the atmosphere from -19 C to +15 C? I've seen the mathematical explanations and I think they are more conjecture than fact. Something is missing.
It would make much more sense if the rest of the atmospheric gases played a part somehow. I think G&T have raised some excellent points.
Gordon, when did you study physics?
Einstein proved the particle-like behavior of light in 1905.
It's strange that you think that AGW is anti-science. It would seem that it is you that is anti-science because science isn't the way you'd like it.
G&T's argument against the "greenhouse hypothesis", I always thought was quite logical.
Particularly where they say that the world has a confused concept of what Arrhenius' original proposition of the "greenhouse effect" really is and our atmosphere that is open, revolving, turbulent and chaotic and should never be described in those terms.
Thank god Arrhenius never had GCMs.
Spangled, you should do more research on Arrhenius. Whatever your thoughts on AGW or the Greenhouse Effect, he was quite a scientist.
Cohenite, here's a new papaer on the Tropical Tropospheric temps…
http://www3.interscience.wiley.com/journal/121433727/abstract?CRETRY=1&SRETRY=0
Brand new, just out.
Is this the proof you were looking for?
Arrhenius inverted the burden of proof for this ice age theory – not such a scientist after all.
NT "Spangled, you should do more research on Arrhenius".
NT…I'm sure Arrhenius was a good scientist in his day as were many others of that era. As you know, Beck compiled a good list of work done by such scientists on atmospheric CO2 density in a similar era to Arrhenius, some of them Nobelists, yet they were ignored by the IPCC because the CO2 densities they reported did not support the IPCC anthropogenic warming theory.
I'm willing to be open-minded and respectful of Arrhenius but I wonder why so many people dismiss outright the work done by some of his peers?
Arrhenius developed the Arrhenius Equation. Look it up.
Perhaps their work was dismissed because it is wrong.
NT; your link doesn't work.
NT…"Einstein proved the particle-like behavior of light in 1905″.
I wasn't talking about light I was talking about a beam of electrons. The initial question was about my understanding of photons to which I replied it wasn't a lot. I also infered that no one else knew a lot about photons either.
It wasn't till 1925 that Heisenberg and Schrodinger foisted the concept of quantum mechanics on us. Einstein did not agree with a lot of it. It is in the modern field of QM that electrons are being compared to both waves and particles. Of course, they talk about cats in a box being alive, dead, or alive and dead (Schrodinger's Cat). It's that sort of mental bs I'm talking about.
There's a danger with thought experiments in that you can miss the lies in them because the human brain has difficulty seeing its own bs. For example the thought experiment in which a twin leaves on a space craft at the speed of light, leaving his twin behind. On his return many years later, he is younger than the twin who was left behind.
It only takes a basic understanding of time to see the lie in that. Humans don't age because of elapsed time, they age due to a biochemical process. Traveling at the speed of light wont affect that process, yet there are scientists who don't understand that. They see time as a real entity that clocks measure. Standard clocks that are wound up are machines and have no relation to time, which is an illusion anyway.
The concept of photons is harmless enough but the more diabolical theories of QM need to be put away and some good research done. David Bohm was one of the leading authorities on QM and relativity and expressed a concern about that. He understood the distortions inherent in the human mind because he studied the mind and it's operation as well as external phenomena. He suggested we've gone too far with our bs in physics and will need to step back and do better observation.
I would take that even farther with climate science. Some of those guys should go back to school and relearn their physics.
NT…just to continue this a bit…consider light itself. It is reported to be an electric field combined with a magnetic field. If you have an electrical circuit, say with a battery, the battery supplies the electric field. Current (charges) moving in a conductor supply the magnetic field, which operates perpendicular to the electric field and both are perpendicular to the current vector.
Light is made up of electric and magnetic fields. It operates as vibrations in space. The human eye has receptors that are stimulated by those vibrations to produce colours. However, the interpretation of those signals is done at a deeper level in the brain. Quite obviouxly, without eyes, the human could not experience light as he/she does. It is the human mind that brings us all the theories on what light is and we should keep that firmly in mind. Other than those pathetic theories, we know nothing about light and the photons to which we refer are imaginary concepts of the mind. We have no idea what light is or where it comes from.
Louis has mentioned electricity in space and we know electric fields normally come from potential fields involving electric charges. We also know magnetic fields come from moving charges. Other than that, what do we know about light?
If it is a particle, how does one explain the 3-dimensional dispersal of light from a source? If it is a wave, where are the electric fields and charges that produce it?
This one should wrok Cohenite, apologies.
http:www.gfdl.noaa.gov/reference/bibliography/forthcoming/bds0801_man.html
Gordon, the problems lies with language, not with science.
Photons are neither waves nor particles, but have properties of both. We don't have a word for such an entity.
I agree with you about the illusory nature of time ( or at least I believe time is more likely to be illusory).
If you think those theories are pathetic, fine.
Comment from Gordon Robertson
Time October 13, 2008 at 3:18 pm
And how do you know about electric fields and charges? They are imaginary also except for the sparks when you rub the cat.
Maxwell's equations have given us with a beautiful precision among other things all we know about light as waves. They also led into special relativity.
Quantum mechanics has given us the transistor and chip age, lazers, again with miraculous accuracy. Photons as particles are used all over the place in astronomy, electronics, medicine etc.
You are sitting and typing on this board because Maxwell's equations and Schroedinger's equations work to a great accuracy.
Maybe there will be more encompassing practical equations in the future, but they still will have to embed Maxwell's equations and Schroedinger's equations.
Of course everybody is free to reinvent the wheel, or even steal fire from the gods.
cohenite "…the conclusion at 2.1.5 typifies this…"
With respect to 2.1.5…they are saying basically that the AGW theorists applied Boltzmann's equation in the wrong manner. It only applies over a smooth curve, not over bands of radiation as applied in AGW theory. In other words, you can't integrate over a discontinuous curve, especially with discrete IR bands in it.
Also, G&T are claiming the constant phi in (28) is strongly dependent on geometry and you can't use simple Poynting vectors as they seem to have done. Poynting vectors are used in well-defined fields like electric fields. I think G&T are claiming this: if you're going to integrate a differential (dv in (26) page 20) from 0 to infinity, you can't use Poynting vectors as the differential quantity since classical radiation theory requires far more complex vectors.
The equation in (26) is essentially summing the radiation lines emitted from a flat surface over a hemisphere. To do that, you have to sum an infinite number of lines over the entire radiation spectrum for Boltzmann to apply.
But, hey…anything goes in AGW theory. Section 2.5.1 is only a small sampling of the bs that goes on in AGW theory.
anna v "And how do you know about electric fields and charges? They are imaginary also except for the sparks when you rub the cat….Quantum mechanics has given us the transistor and chip age…"
You're missing my point Anna. I'm not disputing reality, I'm disputing the ability of the human mind to interpret it. I did not claim that light or electricity had no existence, I was only claiming the human mind has distorted ideas about the reality of phenomena. Time most definitely has no existence except as a concept in the human mind.
With respect to transistors, I think you are giving far too much credit to QM. Transistors were invented in a lab by people putting pieces of semiconductor material together. Much of that theory came from the study of crystal lattice structure, not from QM. Transistors were developed out of a need to replace the more unwieldy vacuum tubes, not from an exercise in QM.
http://inventors.about.com/library/weekly/aa061698.htm
When you look at it more closely, the only practical use of QM is theorizing about atomic and sub-atomic particles. If you think scientists who work in semiconductor and laser labs are sitting around discussing quantum theory, I'm afraid you're in for a bit of a shock (no pun intended).
NT "If you think those theories are pathetic, fine".
If scientists would make their observations and present them as the theories they are, I'd have no problem with that. When someone like Carl Sagan or Stephen Hawking states, "When the Big Bang happened…", I have serious problems with that.
Can you understand what I'm saying? I have no problems with people talking about photons, or electrons. We have to give terms to phenomena that people understand, even using time as a parameter. The issues I have is when people talk about those entities as if they have specific knowledge about them.
I work in the electrical/electronics field and I talk about charges, electrons and voltages all the time. I have no problem doing so because it's functional. For someone to expound on what an electron is mathematically, talking about it's spin, for example, as if the electron is a little orb with spin, I don't have any compuction about telling them to p*** off.
I really hate the smugness I encounter when reading articles about QM. Half those people don't even have the intelligence to make a relationship work yet they are willing to talk confidently about an electron's spin and the probability of finding it at a certain location.
I'll tell them what. Take a 200 foot conductor and tell me where to find an electron in it. After that, I'll connect them to a 347 volt potential and let them guess where the rest are.
Gordon; we must have a good old thrashing of QM one day; I'm a bit of a fan of Brane theory myself with gravity an interloper.
NT; your link to the Santer et al paper and the 'new' concordance between the modelled THS and observed data; Randall and Herman did an analysis of the warming bias of RSS (which Santer uses) this year; Douglass and Christy rely on Randall's paper to select UAH data as their basis for establishing a CO2 signal; however, both RSS and UAH have been found to have warming biases;
http://www.worldclimatereport.com/index.php/2008/01/08/musings-on-satellite-temperatures/
As well, despite a slight troposphere warming since 1979, over the last 5 years that has been replaced by a cooling trend;
http://wattsupwiththat.files.wordpress.com/2008/08/hadat2_2003-2008.png
Why doesn't Anthony plot his graphs the other way round… With high altitude lines at the top… Anyway, not sure what to make of that mess. Doesn't seem to be going anywhere. The graphs provided by the Hadley Centre are much easier to read…
Note the Santos paper is looking at Tropical Troposphere, not the global.
Hmmm Warming bias of RSS and UAH…
So what dataset do you use? Presumably GISStemp and HadCRUTv3 are out?
NT: "So what dataset do you use?"
Confusing makeovers from Lucia of course. Divide and rule?
If we needed to control some event based on the type of display in that link above even the more experienced teams would revert to using their most colourful language in response to any conclusions
'Why doesn't Anthony plot his graphs the other way round…With high altitude lines at the top.."
Have you looked at the way Hadley plot their graphs? Anyway, if it's a problem, just stand on your head.
Your ability to understand science.
Gavin the problem with using Lucia's data then is that it is all wrong… Oh well, guess Lucia will have to set up her own network and calculate her own scheme of Global temp.
SJT that made me laugh out loud…
Cohenite if I stand on my head then the trend is reversed… It's a no win.
Cohenite, Hadley graphs are much easier to read
http://hadobs.metoffice.com/hadat/images.html
Really NT; globally there was some slight ENSO upward trend at the surface and troposphere; even less in the tropics; no THS; in the stratosphere definitely some downward trend from 1990; but then some downward trends here;
http://wattsupwiththat.files.wordpress.com/2008/06/livingston-penn-fig2.png
QM, Relativity are all abstractions of some think physical reality is.
Einstein never did physical experimentation and after his, well deserved paper on the photoelectric effect that got him the Nobel Prize, his subsequent scientific worked lost its way in mathematical abstractions as a result of his gendakenexperimentium.
The same theoretical affliction enthralls the economic profession which produced the current financial crisis.
I seem to have an aggresive spell checker…….
True. In effect we are each a construct of our brain. How do you know there is anything outside your brain?
Nevertheless.s is a nihilistic hypothesis.
"With respect to transistors, I think you are giving far too much credit to QM. Transistors were invented in a lab by people putting pieces of semiconductor material together. Much of that theory came from the study of crystal lattice structure, not from QM."
Crystal lattice IS quantum mechanics. Xrays etc.
" Transistors were developed out of a need to replace the more unwieldy vacuum tubes, not from an exercise in QM. "
It used it though, diodes and energy bands etc.
"When you look at it more closely, the only practical use of QM is theorizing about atomic and sub-atomic particles. If you think scientists who work in semiconductor and laser labs are sitting around discussing quantum theory, I'm afraid you're in for a bit of a shock (no pun intended). "
You have forgotten "nuclear" which has mankind by the @#$%.
You are wrong. Even if maxwell's equations and schroedinger's equations had only organized our knowledge for us in a compact easily calculable system it would still be a great discovery.
The geocentric system worked just by adding epicycles. It still does. There are no more parameters than there are in the heliocentric one. Nevertheless the elegance of Newton's gravity formulation not only trumped the old system ( still surviving in astrology) but allowed easy computations and predictions.
Physicists do no believe in models based on EM and QM out of fashion or orthodoxy. They use them because their predictive accuracy is enormous in all fields and has not been falsified as far as I know in anything.
As I said, you can believe that one has to invent the wheel, even when wheels are all over the place.
Also, G&T are claiming the constant phi in (28) is strongly dependent on geometry and you can't use simple Poynting vectors as they seem to have done. Poynting vectors are used in well-defined fields like electric fields. I think G&T are claiming this: if you're going to integrate a differential (dv in (26) page 20) from 0 to infinity, you can't use Poynting vectors as the differential quantity since classical radiation theory requires far more complex vectors. "
I am with you on this and with G&T. The first thing I observed when I started delving into "climate theory" was that they were mixing their systems of calculation, quantum mechanical systems, as absorption lines are, and thermodynamic ones which know nothing of quantum mechanics.
I still do not understand why CO2 cannot be treated as a factor changing the heat capacity of the atmosphere, and the whole climate as a complicated heat engine with many sources and sinks. ( one needs complexity theories for this though).
hum says
Anna,you may want to rephrase this statement: "Quantum mechanics has given us the transistor and chip age, lazers, again with miraculous accuracy. Photons as particles are used all over the place in astronomy, electronics, medicine etc."
Quantum mechanics at the time the Laser was invented specifically stated that a laser was impossible. QM is nothing more than a mathematical representation of reality with too many paramatizations. Feeman Dyson had a conversation with Fermi: "In desperation I asked Fermi whether he was not impressed by the agreement between our calculated numbers and his measured numbers. He replied, "How many arbitrary parameters did you use for your calculations?" I thought for a moment about our cut-off procedures and said, "Four." He said, "I remember my friend Johnny von Neumann used to say, with four parameters I can fit an elephant, and with five I can make him wiggle his trunk."
Arthur Smith says
Well, this is interesting ("NT" in email hinted there was a discussion here but I didn't realize it was actually about my article!).
First, Jennifer, thanks for the comments – you're quite right that my analysis in that paper says nothing about the influence of CO2 – it neglects the spectral dependence of absorption completely other than to assume distinct average long-wavelength and short-wavelength ("infrared" and "incoming solar") behavior. It does say something about convection: since convection cannot remove energy from the planet, its only effect is to redistribute it across the surface in some manner. Convection cannot explain the observed 33 K discrepancy between incoming solar energy and Earth's surface temperatures, or even a 1 K discrepancy. Without GHG's (and other infrared absorbers like clouds), convection can only bring surface temperatures to a more uniform state closer to the 255 K average, it can't raise the average surface temperature any higher than that.
Contrary to Jeff Id's assumption, I see the comments prove a number of people really do dispute the basic greenhouse effect. Much reference has been made to Gerlich and Tscheuschner's article, of which my paper was a response to only one (but what seemed to me central) section. A more thorough analysis of the G&T paper has been made by Jochen Ebel – unfortunately for those who are not native speakers, it is in German:
http://www.ing-buero-ebel.de/Treib/Hauptseite.pdf
I have access to an English translation of this but it doesn't appear to be online anywhere at this point; those interested may wish to ask Ebel himself for a copy, he can be contacted at jebel AT t-online.de
"cohenite" above linked to a draft paper of mine that Viscount Monckton had unfortunately prematurely published, with his commentary. I have a significantly revised (and shortened) version that has been submitted to the newsletter in question, which I am not inclined to publish anywhere else until I hear definitely whether they will use it or not. Meanwhile, I do have a more complete analysis of Monckton's Physics and Society article available online for those interested in a point-by-point response:
http://www.altenergyaction.org/Monckton.html
anna v: "I still do not understand why CO2 cannot be treated as a factor changing the heat capacity of the atmosphere, and the whole climate as a complicated heat engine with many sources and sinks. ( one needs complexity theories for this though)."
With you on the heat engine but how CO2 changes the heat capacity has me wondering. Do you perhaps mean the capacity of the atmosphere to transport heat (absorb, emit diffuse)?
Debate in this thread has reached now a very interesting phase. Our concept of the universe should not be hung up in this or that language. To me the most frightening aspect of all physics is our inability to convey verbally and in the written form what we see in other perspectives. Math has evolved somewhat in parallel with our quest for an appropriate form of communication for ideas in science. But do the laws and the math as developed to date in physics fully explain what we think we know?
We still have significant problems with dimensions too. In my discussions with Gordon, I tried to explain how we can cross boundaries in theoretical v practical appreciation with most applications. For me it quickly became the case of not bothering with the deeper Fourier type processing then getting on with what actually happens at various points in the electromagnetic spectrum. Also other classical treatments such as quantum physics has limits too.
A true master should know how to tune a resonating cavity or turn it into a modulator or detector like a crystal.
It's well to remember that neither the transparent atmosphere we have, or the space around it offer much in attenuation to virtually the whole energy spectrum. However any discontinuity out there plays havoc with the math and our expectations. More likely at these junctions we need to change our concepts and physics.
IMO the idea of optical depth in climate science is a worry. If it is only a bulk commodity for a simple model, it's OK but from fluid dynamics we get layers of gases and vapours even as they circulate. In a column, they are neatly stacked above the liquids and that should start us wondering where CO2 end up in the soup rather than bothering with what speed its molecules vibrate while rising from the stack. Btw we did a lot of work re waste heat and unburnt fuel during our transition to clean air above cities. Dirty maths hey.
"the whole climate as a complicated heat engine with many sources and sinks" Sure but let's not look for copouts as the main way of dealing with a man made mess
To me the focus of climate studies must remain at sea level and on sea level because this is the major junction in all heat engine calculations where SL becomes the barometer of change. The next consideration re major discontinuities must be clouds and these too tend to form layers. From radio propogation experience rain is another barrier. Also condensation generally needs to be know for our heat exchanger calcs in the column.
Arthur; keep up the good work.
Cohenite, don't be scared, talk to Arthur, see he's friendly!
BillG says
The reason the surface temperature (Air temperature 2m from the ground) is higher than the effective emission temperature can be explained by gravity. See Thieme's paper located at "Cohenite referenced it in an early comment but no one paid much attention.
Webmaster,
The link for Thieme's paper did not appear in my comment. This is my first post here and I need to learn the rules. The link is:
http://www.geocities.com/atmosco2/atmos.htm
NT; how coy are you; your e-mail only hinted that a discussion was taking place! I'm sure Arthur is a nice bloke; but as I noted above, his assumption that "Similar to the effective albedo, an effective emissivity and effective radiative temperature can be defined as averages over the planetary surface " (p2) can't be sustained; the Essex et al paper on the fallacy of average temperature is one reason; more acutely. as the Pielke paper notes, you cannot standardise SB; G&T note this at FIG 3 on p 20; the constant o~ in SB is not universal because at each point of space many (disparate) rays are associated; as G&T observe the AGW notion of radiative balance which Arthur incorporates into his paper, cannot represent radiation intensities; Gordon comments on this at 4.19pm on 13 oct above in respect of G&T's conclusion at 2.1.5; what Arthur proposes is inconsistent with Stewart's Law (as described in Robitaille's paper) which states that the emissive power of an object is dependent on its nature, its temperature and the frequency of observation; as the Pielke paper shows, a proportion of the radiation emitted at the TOA must originate from the surface; the surface has a great disparity in temp and therefore SB emissivity; the energy distribution curve for those disparate SB values are equally disparate at TOA, and at atmospheric surfaces such as the CEL; if there is not a radiative balance between any surface point and any TOA point the notion of a uniform greenhouse effect cannot be sustained.
G'day Arthur, I not with interest that you still hold that incoming irradiance = outgoing radiance and that the temperature is not changing. Unchanging temperature is the definition of thermal equilibrium as I understand it so with radiance = irradiance and T(t(0)) = T(t(n)) emissivity must also be the same as the absorptivity but you have emissivity set at 1 and absorptivity set at (1-a) ~ .7.
If you set the absorptivity = emissivity you will obtain an effective temperature of about 289 K which is only a 9K difference to the "standard" and 7 K difference with the globally averaged TIGR profiles and this seems a far more reasonable figure than the 33K difference you are pushing.
Cohenite, I was as surprised as you were. I didn't ask him to post here, I told him where the discussion was taking place out of courtesy so he would know where I was thinking of posting his reply (which in the end I didn't).
Anyway you can email him directly with your queries. He's very polite, courteous and succinct.
I am curious why you didn't email him orginally though. Surely if you are interested in understanding it would be best to get it from the horses mouth so to speak.
I am not sure why you say the average temp is a fallacy. It's just an average, yes? Not that contraversial.
Um – cohenite (Oct 14 12:18 pm)? Have you actually read my paper, which Jennifer linked to at the top? I suggest you give it another try. Every one of your issues (as far as I can tell, at least, from your breathless enumeration of them) is specifically addressed in the discussion in that paper. The whole point of it was to discuss specifically the issue of how to calculate an average temperature and the overall rates of thermal radiation for a body that had a "great disparity in temp", and several specific examples are illustrated in detail, as well as the general case. I'm not sure what you mean by a "uniform" greenhouse effect; however there is certainly a significant (33K) discrepancy between observed average Earth surface temperatures and the maximum possible average temperature you could see without greenhouse (or other infrared) absorption by the atmosphere.
Jan Pompe (Oct 14, 12:36) – incoming solar radiation is not in thermal equilibrium with Earth, it is at an effective temperature of some 5000 K (the temperature of the sun's surface). Its range of wavelengths is much shorter than the outgoing (infrared) range that is the issue with greenhouse absorption. Absorptivity and emissivity are wavelength-dependent, as we have discussed before: the 0.7 refers to incoming (short-wavelength) radiation, while 1.0 (or very close to it) applies for outgoing infrared.
In your second paragraph – are you claiming that infrared emissivity of the Earth's surface is only 0.7? This is contrary to a very wide range of observations. Most of Earth's surface is water, for example, with emissivity in the thermal range between 0.94 and 0.99 (for water, ice, or snow); most other ground cover also has emissivity over 0.90. Only a few artificial materials are highly reflecting in the thermal range, and they cover very little of Earth's surface.
Snow has perhaps the most obvious contrast between short-wave and long-wave emissivities: for incoming sunlight, new snow reflects about 80%, with an emissivity of only 0.2. Yet its thermal emissivity is 0.94 or higher. The number depends on wavelength, and we don't have a thermal equilibrium situation for the radiation, so equilibrium arguments don't apply.
Arthur; you assert that the greenhouse effect is responsible for the 33K temp difference between what the constant incoming insolation causes and what is actually the case (summary points 4 & 5). This effect is the product of downward longwave radiation isotropically emitted from atmospheric CO2 adding to the incoming insolation. Could you confirm that this effect is not a result of the insolation energy being increased within the atmospheric system but that energy being 'delayed' from leaving the system. If that is the case then once the greenhouse effect is established on the basis of a constant insolation and constant delaying mechanism (ie absorption) then increasing the delaying mechanism (ie absorption) also will not increase the energy within the system because of the operation of Stewart's Law which states;
"when an object is studied in thermal equilibrium, its absorption is equal to its emission."
Thus, if the absorption is increased then so to will be the emission.
anna v said…"I still do not understand why CO2 cannot be treated as a factor changing the heat capacity of the atmosphere, and the whole climate as a complicated heat engine with many sources and sinks. ( one needs complexity theories for this though)".
anna…just came across this statement from Feynman, "The first principle is that you must not fool yourself and you are the easiest person to fool".
That's the premise of my arguments against CO2 warming. I don't pretend to understand in-depth physics and mathematics but I'm an expert on fooling myself. I started working on that about 20 years ago and I'm just begining to scratch the surface on how easily humans are fooled by their own minds.
I have been reading different articles for several hours today and one of them claimed the atmosphere makes a lousy heat engine. A calculation revealed a 23% efficiency, and as you point out, the system is far more complex than a Carnot engine. Maybe there's something wrong with my reasoning, but it would seem the atmosphere would need an efficiency of over 100% to get the heat gain predicted by AGW theory. As we know, those kinds of engines don't exist.
One thing I did learn at university was to look at the answer to a problem to see if it was even in the ballpark. As an engineering undergrad, I was taught to check my solutions as I worked them out. I remember one problem in dynamics involving a spacecraft approaching Mars. We were to calculate how many seconds a retro-rocket would have to be fired in order to slow the craft enough to go into orbit.
I was immediately bothered by the the initial velocity of the craft and it's proximity to Mars. Intuitively, it occured to me that it would be well past Mars before the retro's could be fired effectively.
I took to it to the TA (teaching assistant), a Ph.D in physics, and he just shrugged, advising me to work it out anyway. I persisted, and he brought over the engineering prof in charge of the tutorial. He laughed and told me I was right but just to work the problem through anyway.
In university, especially on exams, I found myself faced with problems that had other solutions, depending on how I looked at the problem. That was a problem of mine, reading too much into the questions. Then, again, how is a student to know what a prof is thinking when he makes up an exam?
Intuitively, I am deeply bothered by the sparseness of CO2 in the atmosphere. Even water vapour accounts for only 1% of the atmospheric gases. Try to visualize a 380 ppmv density by breaking it down to 38 molecules of CO2 per 100,000 molecules of air instead of parts per million. Imagine 100,000 people in a sports stadium with 38 of them representing the CO2.
That 38 molecules per 100,000 molecules of air is the total CO2 in the atmosphere, 97% of which comes from natural sources. The human contribution is about 1 molecule of CO2 per 100,000 molecules of air. So, now we're playing 'try to spot the CO2 molecule' that will heat the atmosphere to it's tipping point.
Spencer has calculated that humans contribute 1 molecule of CO2 to 100,000 molecules of air 'every 5 years'. He bases that on an anthropogenic contribution of 0.6 % per year and the fact that the ocean and land sinks reabsorb 98.5% of atmospheric CO2. He also thinks that the warming in the atmosphere, involving precipitation systems, is far more complicated than the AGW theory implies.
I realize that intuition doesn't cut it in science, although consensus is making great inroads. Let's look at something else. That CO2 is supposed to warm the atmosphere as it increases in density. Since 1995, except for an El Nino warmed 1998, the atmospheric warming trend has been flat. What happened to the warming? Computer models have predicted 1.5 times the warming, and more, but it has not materialized.
We now have a very rare gas and the warming has stopped. What's wrong with that scenario?
SJT "Your ability to understand science".
The difference between me and you is that I don't blindly accept everything I'm told. It's easy to be a parrot, much more difficult to seek the truth.
anna v "True. In effect we are each a construct of our brain. How do you know there is anything outside your brain"?
who is asking the question? 🙂
cohenite (Oct 14, 3:57 pm) – I'm not sure I understand what you are asking, but let me break it down a bit to try to clarify the issues:
"Could you confirm that this effect is not a result of the insolation energy being increased within the atmospheric system but that energy being 'delayed' from leaving the system."
We have, in this system, fluxes of energy coming from the sun to the earth, between Earth's surface and atmosphere, and from Earth into space. A flux is a rate, a quantity per unit time. Any time the incoming flux doesn't match the outgoing flux, whether from changing solar radiance, changing albedo of the planet, or a change in these greenhouse gases that alter the Earth-atmosphere and Earth-space fluxes, then you have an imbalance in energy flows. That imbalance means the total stored energy in the Earth-atmosphere system must change. If you have decreased the outgoing flux while maintaining the incoming flux, which is what happens when you add greenhouse gases, then the stored energy in the Earth-atmosphere system necessarily increases.
Think of a bank account that on average over a month balances out between deposits (income) and expenses; if you reduce expenses for a while from that balance situation, then the amount in the account will necessarily grow. You can think of it as "delaying" the money from leaving the account, or as increasing the income that you are saving, it's the same effect.
"the greenhouse effect is […] constant delaying mechanism (ie absorption)"
Why do you say the "delaying mechanism (absorption)" is constant? Increasing greenhouse gases causes greater absorption at least in the upper reaches of the atmosphere, and reduces the outgoing energy flux, until the system responds and re-balances at a higher stored-energy level.
"[…] will not increase the energy within the system because of the operation of Stewart's Law which states;
What object are you referring to that is in thermal equilibrium here? The whole point is that the radiation field within Earth's atmosphere is *not* in thermal equilibrium, and therefore absorption and emission are not equal. The atmosphere can mostly be described by local thermal equilibrium where the intensive properties, absorptivity and emissivity, are equal at any given location, but that doesn't seem related to your claim or to the question of how the energy fluxes respond as greenhouse gas levels change.
Arthur Smith: " incoming solar radiation is not in thermal equilibrium with Earth, it is at an effective temperature of some 5000 K (the temperature of the sun's surface). "
Ok let's try some consistency and measure the effective temperature of the sun at the earth's orbit the same way the effective temperature of the earth is measured by measuring the radiation intensity. Solar constant is ~1366 W/m^2 so effective temperature assuming an emissivity of 1 the effective temperature then is (1366/5.27E-8)^.25 = 394K. Now I agree that the earth is not in equilibrium with the sun but Kirchoff's law does not refer to two bodies just one. That is the second thing you need to get right. As for the first the moon presents a given spot on it's surfaces for about 14 days so it might reach some sort of equilibrium with the sun so how hot does the moon get on it's sunny side IIRC ~400K so we are in the ball park. Now back to second from wikipedia (a fair dictionary and wouldn't use it for much more) "At thermal equilibrium, the emissivity of a body (or surface) equals its absorptivity." note it says *a* body! Now in your paper you have "If it didn't average to zero for a long period of time, the energy of the planet
So you are describing the earth as a body in thermal equilibrium i.e. one whose emissions equals its absorptions therefore its emissivity = its absorptivity. The error lies in the fact that you are measuring the its albedo or reflectivity and thus also the absorptivity from space but the emissivity from the surface. Now since when has it been valid physics to measure these parameters of a single body from different surfaces one inside the other?
Incoming and out going
Jan – The question is not "the effective temperature of the sun at earth's orbit", what I referred to was the "effective temperature " of "incoming solar radiation". This is well-determined by the actual spectrum of radiation, according to Planck's law. It's how we determine the black-body temperature of the universal microwave background, by looking at the spectrum of that background, where its peak intensity is, etc. It's how we determine the temperature of the (photospheres of the) stars. And it's how we know the temperature of the Sun's emitting surface as well: the actual wavelength of the peak in the spectrum, and the shape around that peak. Effective temperature for electromagnetic radiation is not determined by intensity – otherwise we'd measure the temperatures of the distant stars as some very tiny amount. It's measured by the spectrum, both the shape and the position of the peak.
This effective temperature determines the maximum possible temperature you can reach by physical manipulation of the radiation, without adding further energy. For example you can concentrate the incoming rays of the sun with a parabolic mirror: the maximum temperature you can possible reach at the focal point is that same 5000 K. It is an "effective" temperature because the incoming solar rays are not in a thermal equilibrium state, so they don't have a temperature as it is usually defined. Nevertheless their spectral distribution does closely match the Planck law at that high temperature, and their wavelengths are much shorter than the infrared radiation associated with thermal equilibrium at Earth surface temperatures. In particular, they are strongly reflected by clouds, snow, and ice, while the longer wavelength radiation from Earth is strongly absorbed by all three; this accounts for the difference between the 0.7 emissivity at short wavelengths and 1.0 at long.
Secondly, I most emphatically *do not* describe the earth as a body in thermal equilibrium. The earth is in (close to) a steady state, where on average incoming and outgoing energy fluxes must cancel one another out; this is often referred to as radiative equilibrium, but it is a very different thing from thermal equilibrium.
There are many ways in which the Earth is clearly not in thermal equilibrium – one of the most obvious is that in thermal equilibrium, every process that occurs in one direction must occur with equal probability in the other direction, there is no "arrow of time", and no increase in entropy.
You are correct that in the relevant discussions in my article the albedo refers to the value from space (for short wavelengths) which is what you need to find the fraction of the Sun's incoming energy that we receive, and the emissivity refers to the value for the surface (for infrared), which is what you need to apply the Stefan-Boltzmann equation for outgoing thermal radiation. They are different, and they refer to completely different processes. What's your question?
NT: "I am not sure why you say the average temp is a fallacy. It's an average, yes? Not that contraversial."
Look at it this way: the average voltage in a 350Kv power line is 0v.
An average is really only a concept, with no real practical value.
With temperatures, the average is really meaningless when you consider that just the diurnal temperature range alone at any location can be several tens of degrees.
Yet the voltage on the power line is not 350KV exactly, is it. It varies, and so it will have an average value, and a variance. Sometimes it will be 350.001KV, sometimes 349.99KV. The average may well be 350.1KV. You just have to use your grey matter to come up with a measurement that makes sense in the context you are using.
Peter, go read Arthur Smith's Arxiv paper, he shows how to meaningfully define an average temperature. But before you do that, you should realize that what is computed is an average temperature ANOMOLY, the difference between the temperature at a location and its average value over a period of time (usually thirty years) in the same month.
If we compared this with your AC voltage measurement, if the answer is not O V (or OC) it indicates a DC bias, and if the difference keeps growing, it indicates a trend.
Jan Pompe should realize that the temperature of sunlight is defined by the wavelength distribution which fits a black body curve of 5000 K.
You assume too much. I don't accept everything I am told, but I also accept my limitations, and when to defer to an authority.
Eli And Arthur do either of you think you can make a solar oven that will achieve temperature of 5000K without concentrating the sunlight from over a large area?
We are not interested here in how the temperature of the surface of the sun is measured but the ability of the radiation from the sun to heat an object at earths orbit. Over ~ 14 days of exposure the surface of the moon gets no hotter than 400K.
" this is often referred to as radiative equilibrium, but it is a very different thing from thermal equilibrium."
Arthur Is the temperature changing in either rising or falling cumulatively in your model you say it isn't so in your model you are effectively defining it as being in thermal equilibrium evading the use of the term does not make it otherwise. You say the entropy in your model is not changing either so neither temperature nor heat content is changing and is another sign that the planet in your model is in thermal equilibrium.
My question is why are you measuring albedo and emissivity from different surfaces the top of atmosphere for incoming and solid surface several miles below the TOA for out going? They are different things apples and oranges. A problem further compounded by the fact the measured temperature is is that of the atmosphere at 1.5 m not a black body at all. Usually absorptivity, reflectivity and emissivity are measured from the same surface not different ones.
Not the banking analogy! I would've thought that given the current credit apocalypse this analogy would have no currency. But Greenhouse is based on this; extra CO2 trapping and delaying upward LW radiation; the more CO2, the more trapping and the more opaque, thermal blankets are wrapped around the Earth. Some things wrong with this; and I note Jan has already referred to the interchangeability of radiation and thermal properties so I won't comment on that; I note in Arthur's last reply to me he describes the greenhouse effect as being a product of the "stored energy in the Earth-atmosphere system', so I'll stick with that;
1 The interest in the banking system is the extra downward LW which increasing CO2 isotropically emits back to Earth; this interest/energy is taxed by the decline in relative humidity (RH); RH has been declining since the latter part of the 20thC; with less RH there is less latent heat and energy; clouds would also increase as a by-product of more energy reaching the surface; with more clouds, more incoming SW would be reflected and there would be less upward LW for the increasing CO2 to send back to the surface; this is part of Miskolczi territory.
2 The typical greenhouse energy flux diagram showing the movement in and out of the Earth's atmosphere doesn't show diffrent radiation intensities; G&T note this at p 20 FIG 3, and Pielke describes this discrepancy in his paper;
http://climatesci.colorado.edu/publications/pdf/R-321.pdf
Greenouse is based on averaging SB which is an assumption of Arthur's paper; this is unrealistic because it averages the energy distribution curve at that SB point as well; not all upward LW is equal as Pielke notes "A 1C increase in the polar latitudes in the winter, for example, would have much less of an effect on the change of longwave emission than a 1C increase in the tropics." AIRS has shown that CO2 is not evenly mixed; where upward LW is being trapped may be compensated by the energy equivalent of upward LW leaving the atmosphere through windows elsewhere. It's like having a number of bank accounts; some are accruing interest without being taxed; some are being taxed and some are your current accounts with no interest at all; this is why the notion of averaging anything, temp, SB, is inappropriate.
3 Arthur, and as far as I know, no greenhouse explanation, doesn't consider atmospheric pressure as contributing to the temp profile; can Arthur honestly say that the surface temp of Venus has no imput from the weight and consequent pressure of its atmosphere? And if he can and say Venus's temp is entirely to do with its banking system with 96% CO2 then how does he explain Mars with 95% CO2?
4 The facts don't match the theory; if Spencer Weart's semi-infinite, opaque, vertically expanding atmosphere were correct there would be troposphere warming, a hot-spot, and surface increase in temp; I would dispute that there has been much temp increase at all, and what there has been has been due to PDO climate phases;
http://jennifermarohasy.com/blog/2008/10/temperature-trends-and-carbon-dioxide-a-note-from-cohenite/#comments
In addition the greenhouse concept of a cooling stratosphere has been addressed by Spencer and Christy in responding to the Fu et al paper.
5 A final point about interest; Arthur's anaology about layers of CO2 passing and emitting LW up and down like a game of tunnel ball ignores the convective transfer of 'energy' in the atmosphere; Chilingar's paper has noted how this transfer swamps the low level radiative transfer at the surface boundary; the tunnel ball interest transfer in all its agonising slowness is circumvented; the LW laden CO2 is transported to the CEL where the LW cargo is emitted to space; this doesn't mean that emissions don't occur at levels of the atmosphere as eli asserted was a logical conclusion of the Chilingar paper, it simply means there is far less of them then the greenhouse model needs; the lack of warming, or accumulation of interest/energy confirms that.
For some reason the Pielke paper won't show; the reference is;
Roger A Pielke Sr et al; "Unresolved issues with the assessment of multidecadal global land surface temperature trends." Journal of Geophysical Research, vol. 112, D24S08 2007
cohenite: "A 1C increase in the polar latitudes in the winter, for example, would have much less of an effect on the change of longwave emission than a 1C increase in the tropics." AIRS has shown that CO2 is not evenly mixed; where upward LW is being trapped may be compensated by the energy equivalent of upward LW leaving the atmosphere through windows elsewhere. It's like having a number of bank accounts; some are accruing interest without being taxed;"
Given that the absorption at the poles is modified by angle of incidence > 80deg so must be multipied by a cos (theta) |theta >= 80. radiance from the surface need only be modified by emissivity so in a sense it's the low income areas that are the more heavily taxed.
Jan; "the low income areas that are the more heavily taxed"; just like real life; bloody AGW.
cohenite: " just like real life; bloody AGW."
You noticed! Unfortunately remediation will hurt the poor of the world more than the rich.
Actually on the physical side of things it generally means that at the poles whether there is ice or water the outgoing energy to space will always exceed the incoming (the limiting case where incident angle is 90 degrees and cos 90 = 0 so it's difficult to see how retreating ice at the poles can be a positive feedback.
Remembering that last year the global temperature plunged and last years melt was some sort of record. Whether or not it is statistically significant it certainly does not suggest that melting polar ice leads to a warmer climate.
Cohenite. You missed Arthur's reply to your convection claim:
"Arthur's anaology about layers of CO2 passing and emitting LW up and down like a game of tunnel ball ignores the convective transfer of 'energy' in the atmosphere;"
Arthur's earlier statement:
"It does say something about convection: since convection cannot remove energy from the planet, its only effect is to redistribute it across the surface in some manner. Convection cannot explain the observed 33 K discrepancy between incoming solar energy and Earth's surface temperatures, or even a 1 K discrepancy. Without GHG's (and other infrared absorbers like clouds), convection can only bring surface temperatures to a more uniform state closer to the 255 K average, it can't raise the average surface temperature any higher than that."
As to your hotspot, I sent you a link to a new paper, that you casually dismissed. It is interesting that you dismiss things before you read them.
3. I sent you the link to Ray Pierrehumbert's online book about this and again you declined to read it. What process do you think exists? Have you attempted to quantify it?
2. "AIRS has shown that CO2 is not evenly mixed; " That depends on how you define 'evenly mixed' – what criteria are you using?
1. "RH has been declining since the latter part of the 20thC; with less RH there is less latent heat and energy; "
Oh come on Cohenite, we already determined that RH is not a measure of the amount of water in the air. You need to look a SH. RH is temperature dependent. Or are you still of the opnion that the only thing a warmer atmosphere can do is evaporate water? Or was it that the only thing warm air will do is rise. Cohenite, these are just dumb statements and you do yourself discredit by not retracting them.
cohenite – slow down, focus on one thing at a time, if you're actually trying to understand stuff. Have you bothered to carefully read my article, the subject of this blog post, yet?
The "banking" analogy is merely an attempt to describe in more familiar terms the difference between a total quantity and the rate of change of a quantity (and it also usefully captures the differences between instantaneous values and long-term averages and trends, but that's another story.) In any case, I said nothing about "interest" or the present collapse and seriously doubt there is any point in extending the analogy that far.
If you have trouble with banking and money, let's change it to chocolate chip cookies, say. At any given time there's some number of cookies in the cookie jar; when somebody bakes more, the number goes up. When somebody eats one, the number goes down. Over time there's a steady-state balance between baking and eating, if the number of cookies in the jar doesn't relentlessly grow. Now, decrease the rate at which cookies are eaten, and even with no change in the baking rate, the number of cookies in the jar will increase. At some point a steady state will be re-established, perhaps when the jar is full and the cook slows down on the baking, or perhaps when the larger number of cookies attracts a larger group of cookie-eaters. Whatever; in any case the new steady state has the same or lower input rate (cookie-baking rate, or incoming solar irradiance), but on average a higher number of cookies in the jar (higher temperatures on Earth). Does that help?
You quote Pielke: "A 1C increase in the polar latitudes in the winter, for example, would have much less of an effect on the change of longwave emission than a 1C increase in the tropics." – this is precisely the point of the averaging discussion in my paper, it sorts out those issues through the use of mathematical inequalities. Pielke's point only makes the discrepancy between the greenhouse-free Earth and real Earth worse, as I show in that paper. Are you sure you've read it?
You say greenhouse theory "doesn't consider atmospheric pressure as contributing to the temp profile" – I'm not quite sure what you mean, but the tropospheric lapse rate, which is determined by the temperature and pressure profile of the lower atmosphere, is essential to the quantitative calculation of the greenhouse effect for any planet, and in particular the adiabatic stability relationships that govern lapse rate are what determine the temperature profile from the surface to the tropopause. So temperature profile is absolutely (in all quantitative discussions of the effect – read Pierrehumbert's book for instance!) associated with the behavior and magnitude of the atmospheric pressure.
What greenhouse gases do is ensure there is a tropopause; without GHG's (or other infrared absorbers sufficient to give a substantial optical depth at thermal wavelengths), the atmosphere could not lose heat into space, and so would everywhere (on average) be warmer than the surface. More GHG's push the tropopause higher. On Venus the GHG levels and atmospheric density are so high that the troposphere is far larger than Earth's – 60 to 70 km thick. Mars' atmosphere is so thin that its troposphere effectively disappears at night; its optical depth is low thanks to the low pressure (little pressure-induced broadening of CO2 absorption) and the absence of water. Mars's atmosphere simply doesn't have enough infrared absorption, in spite of having quite a bit of CO2, to have any substantial greenhouse warming effect.
So of course pressure matters. But pressure does nothing to warm the surface without infrared absorption (and emission) to induce a troposphere.
Cohenite – you "dispute that there has been much temp increase at all […]"? I'm not sure what I can say to that. Give the latest IPCC report a read, they're pretty enlightening on why they concluded otherwise…
On Chilingar – I haven't read it so have no opinion, but the whole point of infrared absorption by greenhouse gases is that it *reduces* the rate at which the surface can radiate. The GHG's get in the way, they block the radiative path to cooling the surface. That means the surface must cool more by other means than it would otherwise: convection and latent heat transfer, in particular. Nothing new there, it's what the theory has claimed all along. The presence of GHG's *reduces* the relative importance of radiation to other heat transfer methods, in the lower atmosphere. Of course, radiation is still the only mechanism by which energy can leave the planet, which was the main focus of my article, so I didn't get into the issue of other heat transfer mechanisms much there.
Jan Pompe – I emphasize again, in my model, as in the real Earth, there is no thermal equilibrium. I nowhere claim that the "entropy in [my] model is not changing" – in fact, as a steady state system that turns short-wave photons into long-wave photons, it is causing a continual increase in entropy. If it were in thermal equilibrium, then all the outgoing energy would leave precisely as it came in, as short-wave radiation on a tight beam heading straight back to the sun. That is very definitely not my model.
Secondly, perhaps I confused you on albedo and emissivity by not specifying that they refer to different physical domains. So let me state that here. They refer to different domains, they do not refer to the properties of a common physical body. The albedo in my paper refers to the reflectivity of the entire planet at the short wavelengths associated with incoming sunlight. It has to be measured from the top of the atmosphere because that's where the incoming sunlight hits us. The emissivity in my paper refers to the Earth's surface, because that's where the thermal radiation in question originates. Two distinct physical systems, distinct physical questions, there is no direct relationship or constraint between the two quantities at all.
Here is the Tropical Troposphere paper in full:
https:publicaffairs.llnl.gov/news/news_releases/2008/NR-08-10-05-article.pdf
"Remembering that last year the global temperature plunged and last years melt was some sort of record. "
The melt happened between June and September. The temps didn't plunge until after the melt happened (Oct 2007 -> Feb 2008?)
Actually it wasn't really plunging except from Dec -> Jan. Oct and Nov were cooler, but most of the year was quite warm.
Arthur Smith: "entropy in [my] model is not changing"
An earlier post "every process that occurs in one direction must occur with equal probability in the other direction, there is no "arrow of time", and no increase in entropy."
With all dues respect you seem to be spinning different things in and out.
as for thermal equilibrium in your paper "planet On average,
This pretty much describes an object in thermal equilibrium and you base your model, of energy balance or radiative equilibrium, on it.
So there is really no cause to have a different absorptivity and emissivity.
"So let me state that here. They refer to different domains,"
Arthur I am accuately aware that you are doing that and that is precisely what I'm objecting to and I am not in the least questioning it – there is a difference.
"Two distinct physical systems, distinct physical questions, there is no direct relationship or constraint between the two quantities at all."
Exactly apples and oranges now try your calculations with the energy that which actually leaves the system both incoming and outgoing at the same place that's the normal way to measure inward and outward radiation from an object.
peterd says
Note to Gary Gulrud (Oct. 11th, 2:04 am):
The concept of effective temperature can be found in numerous textbooks on atmospheric physics. E.g, C. Bohren and E. Clothiaux, Fundamentals of Atmospheric Radiation (Wiley, 2006): "An average (or better yet, effective) temperature that does have an unambiguous physical meaning is the effective radiative equilibrium temperature Teff of Earth defined as the temperature of a blackbody with a total emission equal to the net solar radiation received by Earth averaged over its entire surface" (p.35)
See also R.M. Goody and J.C.G. Walker, "Atmospheres" (Prentice-Hall, N.J. 1972), pp.46-7.
Oh, but I almost forgot, Gary: you don't read atmospheric physics textbooks, do you?
Jan Pompe, please read more carefully. The antecedent of your quote of my comment that "every process … and no increase of entropy" was the phrase "in thermal equilibrium", itself preceded by the statement: "There are many ways in which the Earth is clearly not in thermal equilibrium – one of the most obvious is …". On the Earth, entropy increases. In thermal equilibrium, entropy does not increase. I was talking about how thermal equilibrium is clearly *different* from the Earth, not the behavior of some model Earth. Thermal equilibrium is irrelevant to the greenhouse issue.
Thermal equilibrium and steady state are two very different conditions. When I talk about "On average,
however, over time, this rate of energy change should come very close to zero" this is a steady-state situation, it is *not* thermal equilibrium. Thermal equilibrium implies much, much more than simply a steady energy level. It implies a constant and uniform temperature in the system, it implies reversibility of all processes, it essentially implies isolation (strictly, that all interactions are with other bodies of the same temperature). This is certainly not the situation for the real Earth, it is not the situation in my model, nor is it the situation for any model of the greenhouse effect. Forget equilibrium, it is not the situation under discussion.
When you say "try your calculations with the energy that which actually leaves the system both incoming and outgoing at the same place" – how would it work out differently? You see the equations and assumptions in my paper – please state specifically which one you think is wrong, and how you would fix it, and then we have common ground to start from. I asked you earlier, do you claim that the emissivity of Earth's surface should be 0.7, not close to 1.0? But that contradicts observations. Or conversely, do you believe that 100% of incoming sunlight is actually absorbed by the surface? But that contradicts observations too. What specifically do you believe is wrong in the analysis?
NT; I read your link, which didn't work at first, to the Santer et al paper, and I replied to it at 5.20pm above; it wasn't a casual dismissal either; I went to some length to compare what Randall and Herman had done and a subsequent analysis of defects and warming bias in both UAH and RSS at Climate Report; in respect of the Santer paper, I could only read the abstract since I don't have the unlimited access which you and luke seem to have; I also read the Fawcett and Jones paper which astonishingly found that an ENSO corrected temp history showed a greater upward trend than an ENSO inclusive history, and I read just about every other bit of fluff you throw at me; so, what's your beef? I concede I'm not going to read the Pierrehumbert effort; as Ian Jolliffe said, life is too short for that.
As for RH; I don't think you understand that RH IS a measure of water vapour; it is the ratio of how much vapour there is with how much water the air could hold at saturation for that temperature; if RH is declining there is less water vapour there, and less energy, to use Arthur's phrase.
I posted you the full pdf a few posts above. how could it be anything but a casual dismissal if you didn't read it?
"and I read just about every other bit of fluff you throw at me;"
Fluff?
And hey you don't have to read all of Pierrehumbert.
My beef is that for someone who declares that they have researched this, you actually haven't done very much. You keep declaring that the atmospheric density should be considered, I point you somewhere that it is and you refuse to read it. You declare that this is terrible science or that it would get thrown out of court, but really all you have is your opinion and your own personal bias.
RH is a measure of the ratio of the amount of water vapour to the amount the air could hold at a particular temp, yes. It is not the amount of water in the air.
If RH is declining it could be that air temp is rising or SH is declining, or both. A decline in RH says nothing about the temp or the SH on it's own. All it tells you is if it is likely to rain.
Thank you Mr Smith, this is very informative. 🙂
Arthur, I think we can dispense with the analogies; they're making me hungry and I'm on a protein diet; you say to Jan that your model doesn't posit thermal equilibrium, but surely this is the essence of the greenhouse; with a constant insolation and no increase in CO2 a "steady state" (p2) will be achieved; the guts of AGW is that increased CO2 is disrupting that thermal equilibruim by creating a radiative disequilibruim; the upward LW plus the downward LW > the incoming SW. This thermal equilibrium is based on the "effective temperature" (p2) which you obtain from averaging temperature to the fourth power, relevant for the thermal radiation problem,"; but this is the problem; you go onto say that this average temperature.. is always less than or equal to the effective thermal radiation temperature." (p3); that is Tave < Teff, but that since Teff is increased by a factor 1/(1-f/2)1/4 (eqns 36-39) due to the greenhouse Tave will be increased as well; but is this necessarily the case? Motl has provided us with an example;
http:motls.blogspot.com/2008/05/average-temperature-vs-average.html (// excluded)
Motl looks at the differences between "the average value of the fourth power of temperature and the fourth power of the average temperature"; that is Tave and Teff; He does so in the context of using global averages and how they can produce misleading 'greenhouse' results. Motl uses 4 climate zones with different average temperatures:
313 K (40C)
263 K (-10C)
The average temp, Tave, is 288 K (15C);
The measure of SB irradiance for 288K (288 to the 4th power x the SB constant, 5.67 x 10-8 W/(m2k)) is 390.08 w/m2; if we SB each of the climate zones average temp, without before averaging them, the measure of irradiance is 399.26 w/m2; a difference of 9w/m2 over whatever time unit. Motl goes on to show that other examples of different climate zone temperature which still average 288K can produce different SB irradiance amounts; the conclusion is that while Tave < Teff, as Arthur notes, the averaging process of SB, Albedo and temp globally masks the fact that regional variations and fluctuations can mean that "the total energy budget of the Earth can be completely unaffected as long as the combined non-uniformities of the temperature (from climate zones; regional albedo variations; day/night differences" stay within the paremeters of the difference between Tave and Teff; which is to say the difference is not a measure of greenhouse but the compensatory capacity of the climate system; the averaging that Arthur uses looks at this from exactly the opposite direction.
NT; I'm exhausting myself talking to your invited guest, Arthur, and all you can do is deride me for not paying attention; I'm damned if I do and damned if I don't! Now, what do you want me to read?
Peter "Look at it this way: the average voltage in a 350Kv power line is 0v".
I don't know where you studied your electrical theory. I presume first of all that you are talking about alternating current transmission as opposed to direct current transmission. Anyway, the average voltage is most certainly not 0 volts.
In North America, we use a single-phase system for residential power. We refer to it normally as 120 volts AC and it is derived from the centre-tap of a 240 volt transformer secondary. That secondary is one phase of a three phase system but the 120 volts is in phase with the 240 volt because it comes from one phase of a 3 phase system. The phasing is pertinent since the system you describe is normally 3 phase.
One cycle of that 120 volts is a pure sine wave. The 120 volts is an RMS value which is the direct current equivalent of that AC voltage. The RMS is derived by talking 0.707 of the sine wave amplitude. The average voltage is 0.636 of the amplitude.
The average is found by summing all the instantaneous values from 0 to pi and computing the average of those value. Over an entire cycle, it could be argued that the positive and negative values cancel, leaving 0 volts overall. This is a perfect example of applying mathematics to physics without thinking. The sine wave is a model and does not represent what is going on in a circuit overall.
120 volts is 0.707 of the sine wave peak which is 169.7 volts. That means a 120 volt AC source starts at 0 volts, rises to 169.7 volts and returns to 0 volts. Then it reverses direction, rising to a negative peak of 169.7 volts and back to 0 volts.
In the electrical field, you are interested in what both halves do to an attached load, like a motor or resistance. It doesn't matter which way the current flows, or which polarity the voltage source has, they both do equal work in a load. You can talk about a 0 volt average if you like but the average voltage used in practice is not based on a full cycle because that average has no meaning in practice. The 350 Kv line you mention is the RMS value between two phases with a phase angle between the voltages, called the line voltage. It is based on 1/2 of a sine wave, not the full cycle.
The RMS value was developed so we would have a DC equivalent voltage for the AC. Since we are interested in the capacity of a voltage to do work, we have no interest in the mathematical average one might take from inspection. We are interested in the actual average voltage over one half of the sine wave.
The average value is particularly important when the sine wave is rectified. That refers to chopping off one side of the sine wave, leaving a pulsing direct current wave, or rectifying both the negative and positive portions leaving two pulses of positive DC. When those pulses are smoothed by a capacitor/inductor/resistor filter, the average value is used.
I would agree with you that the average value is misused on many occasions. For example, what does it mean to talk about an average global temperature? In North America, we had as many warm days between 1920 and 1940 as we did between 1990 and 2008, yet the global average indicates the warmest days ever were between 1990 and 2008. Why do I care about that mathematical analysis when I'm living in North America? Implying that we are going through unprecedented warming based on a mathematical average is about as useless as claiming that the average voltage over one AC cycle is 0. That becomes even more useless when the warming we are talking about is 0.6 C over a century.
Arthur…I have read through your rebuttal in more detail and I must say I am disappointed with the thinness of your main proof of the Greenhouse Effect.
My first concern was your background. Please don't take this as an ad hom attack, or as any other attack, because none is intended. A few of us here are concerned about articles coming out of realclimate written by mathematicians and computer programmers. I do notice you have quoted Pierrehumbert from RC, who I consider to be an activist. Also, I came across a book review on the net, seemingly written by you, in which you endorse Al Gore. If I'm wrong, I apologize.
It seems you got your Ph. D in 1991, in physics (congratulations), from Cornell. Then you worked in particle physics. Now you work for the The American Physical Society, which I believe is a publisher of a scientific journal.
It doesn't seem your background in climate science is that robust. Then again, your way ahead of me academically. I thought it was kind of ballsy for you to take on two theoretical physicists who work in the discipline.
I have cherry-picked statements from your article. Here's one:
"For a planet with no atmosphere, or with an atmosphere that doesn't absorb electromagnetic radiation to any significant degree, all this surface-emitted thermal radiation escapes directly into space".
Question 1: How are GHG's that make up about 1% of the atmosphere going to absorb enough heat to raise the Earth's temperature by 33 degrees C? On the face of it, I would think most of the heat would escape anyway.
Cherry pick #2: "The same is true if we were to add in more realistic horizontal energy transport from larger-scale atmospheric and oceanic circulation – of course getting much more realistic means entering the realm of more full-scale general circulation models, which we have no intention of doing here".
Question 2: Since we know larger GCM's are not reliable, how is your smaller model any better? G&T made a point of the fact that no comparison is made between an Earth with and without an ocean. How do we know what role the oceans ultimately play in the warming?
cherry pick 3 "That means some layer above the surface must be absorbing or reflecting a significant fraction of the outgoing infrared radiation. I.e. the atmosphere must not be transparent to infrared.
….Incoming solar radiation still drives everything – if the solar constant S drops, then so does everything else. But the effect of the absorbing layer is to reduce the final outgoing energy for a given temperature, so the planet heats up until things are back in balance again".
Question: Is that not an incredible leap of faith? Your math is very good, I have no arguement with it. It's just that you do this great build up, then suddenly thrust this theoretical layer into the mix, claiming, it must be so. In other words, there's no other explanation. How about something we don't know about yet, like the other atmospheric gases playing a part in delaying the escape of heat?
cherry pick 4: "Namely that assuming the atmosphere is transparent for visible light but opaque for infrared radiation leads to a warming of the Earth's surface relative to firm limits established by basic physical principles of energy conservation, for the case of an atmosphere transparent to both visible and infrared".
Question: That's a big assumption. Where's the proof arived at by experimentation in the atmosphere? Spencer tells us the satellite telemetry is not sensitive enough to measure such radiation.
Also, G&T tell us climate science is confusing conservation of energy with heat flow. They specifically claim Rahmstorf is wrong with his notion of net energy transfer.
cherry pick 5: "(in your summary)The only way the fourth power of the surface temperature can exceed this limit is to be covered by an atmosphere that is at least partially opaque to infrared radiation. This is the atmospheric greenhouse effect".
Question: once again, is this not a huge leap of faith? I think G&T's arguements against it are far better.
cherry pick 6: "(from summary) The measured average temperature of Earth's surface is 33 degrees C higher than the limit determined by items (2) and (3). Therefore, Earth is proved to have a greenhouse effect of at least 33K".
Question: What have you proved exactly? You inserted a theoretical layer in the atmosphere comprised of gases whose densities are 1% of the atmosphere, and claim that as a proof?
I appreciate you coming on here with your explanations and I hope we can keep it civil. I have no problem with your expose on the atmosphere, or your right to do so, but I would have appreciated it more if you'd given more respect to G&T. I may be wrong, but I sensed an aloofness in your paper much along the lines of Rahmstorf's attack on Lindzen. Also, you overlooked much of what they were talking about.
Maybe I'm reading too much realclimate into your motives. Sorry if that's the case.
Cohenite, what you might consider is not constantly asking the same questions or behaving as though the question hasn't been answered (or at least been pointed in the direction of a possible answer) without reading what has been provided…
So I aksed Arthur Smith about your atmospheric density question. He pointed me at section 4.4 of Pierrehumbert's online book. I think it probably has to do with the notion of transparency, so if the gas is transparent to IR then it doesn't matter how dense you make it. And remember, as Arthur pointed out you can't conduct the heat away from the Earth you have to radiate it.
BTW I didn't invite him. However it has been fortuitous, no? Now you can really discuss the physics and prove that you are right.
I don't understand Motl's four climate zones. Nowhere on Earth averages 40 degrees… He is talking about a different planet?
"you say to Jan that your model doesn't posit thermal equilibrium, but surely this is the essence of the greenhouse; with a constant insolation and no increase in CO2 a "steady state" (p2) will be achieved; the guts of AGW is that increased CO2 is disrupting that thermal equilibruim by creating a radiative disequilibruim;"
As far as I can tell, Arthur is trying to get you to talk the talk. Unless everyone agree's what is being discussed and what the terms mean, the exercise is a waste of time. What you mean by "thermal equilibrium" and what he means are two different things. His definition is the precise scientific meaning, that implies a lot of consequences, that don't apply in the case of the earth and GHG effect.
NT; I think it's great that Arthur's here; maybe we can get Gerlich and Tscheuschner on next.
With the climate zones, if 4 bothers you, you can achieve the same effect with more or less; the point is averaging masks the fallacy of radiative and thermal disequilibrium, it doesn't establish it. Your comment about 40C is gratuitous; you are assuming that it refers to a yearly average; the exercise is valid for any unit of time, and really is only relatable to the measure of incoming radiation; Arthur notes this in the first sentence of section II of his paper; with that in mind go and goggle places on Earth that have had temps of 40C; Marble Bar in Western Australia, where I gather you hail from, averaged over 40C from 31/10/1923-7/4/1924, and peaked at 49.2C.
Alright Will; so I've got it wrong about thermal equilibruim; but if you average global temp, and assert that greenhouse creates a radiative delay, lag, bottleneck, trapdoor or whatever, how else can that radiative imbalance be expressed except as an increase in the so-called average global temp? My point is, by averaging everything that is not nailed down you are creating an artificial (ie doesn't exist in reality) imbalance; hence my reference to Motl.
It all escapes in the end. It's a matter of the rate it escapes at.
Wikipedia has a good explanation.
http://www.ucar.edu/learn/1_3_1.htm
Cohenite, what it means is that his 'method' of calculating global temp is poor. I would suspect that his version of global average temp is not the version that Arthur Smith describes. A daily average temp is typically the difference between the maxima and minima, not just the maxima.
Marble Bar is an amazing place, I think last year they broke the record for the most days in a row over 38 C. Actually the northwest of WA has been remarkably hot during Spt and Oct. They're running days over 40 already.
Maybe you should actually find out what the average temp is.
If you can get D and T on that would be ace! Or if you suggest it to them and they turn up that would be great. 🙂
SJT raises a valid point. We often get two levels of debate on these climate blogs. One level has some good physics while the other has dumb arguments such as the average of an AC voltage is zero. Anyone who has worked in the electrical game knows there is a also current 90 deg out of phase with that voltage when power "flows" along the line.
When Gordon launched into his deep understanding of electricity and the North American grid format I expected the full delta star treatment to follow. What we are left with is half a handful of understanding in real climate mechanics despite all the AC, DC and other bright sparks. Sorry Gordon it had to be said and I do respect your sincerity.
"I thought it was kind of ballsy for you to take on two theoretical physicists who work in the discipline"
Let's say it again, imo Arthurs essay in response to Gerlich and Tscheuschner's article is a sound treatment of the greenhouse issue with classic math and physics. Disappointing as it may be for some, we don't need CO2 to see how it works in general.
There was a mention of Motl somewhere (I shudder again). IMO he does not come across as a climate expert (Gordon's desire for our discipline) despite his charm. Besides, climate science does not lie in blogsphere.
It's this tendency of commentators to depend entirely on blogs that truly leaves me cold.
NT; Motl's piece considers diurnal range amongst all the other factors that produce variations in SB and consequent emission from that surface or location; the point is, the great variation over time between locations means the total energy budget doesn't vary; what Arthur does is define the difference between Tave and Teff as being evidence of greenhouse; what Motl suggests is that difference is the capacity of the Earth to adjust to regionalised energy deficeits; I think we are talking about the same thing, just looking at it from different perspectives. From the perspective of AGW the global average is essential; from a regional perspective it simply presents a false picture.
"truly leaves me cold"; move to Marble Bar Gavin.
Cohenite, yes we may be talking about the same thing. I think we'd probably both agree it was boring…
"From the perspective of AGW the global average is essential; from a regional perspective it simply presents a false picture."
I don't agree that global average temp is essential to AGW. It is just a measure, I guess like inflation, that is very broad and not particularly useful for much. The choice of this as a measure was driven by the availabe data – the historic max and min data. Ideally a different measure would be used, something that better quantifies what is happening.
Disproving the 'existence' of Global average temp is a strawman and it doesn't 'disprove' AGW.
Well, ok NT, if average global temp is a strawman what then is the measure of AGW? I should add that after rereading Arthur's paper I'm not sure he does measure the greenhouse on the basis of the difference between Tave and Teff; the relationship is that Tave is always less or = to Teff; Teff is increased by the greenhouse effect of blocked upward LW, and Tave increases beyond what it would be in a transparent atmosphere because of its relationship with Teff, as defined at equations 10-12; we may not be talking about exactly the same thing after all; I'll sleep on it; maybe Arthur can shed some light.
This boring? Nah.
Cohenite, I said disproving the existence of Global average temp is a strawman. For a lawyer you don't read very well… 🙂
And yes, it is the method of measuring of AGW. And it is not optimal, and everyone knows this. BUT is the measure we use probably for the reasons I outlined above.
I would think that Arthur used a different measure than Tmax – Tmin. How could he use that? The theory is not based on surface temperature readings – it is based on observations of the physical properties of a few gases. He uses one based on the emittied IR or something, yes?
I just said we may be talking about the same thing so we could stop talking about it… It is pretty boring. Makes relative humidity seem simply thrilling.
Hot day in Perth today. And humid we had one of those troughs off the coast I was speaking about today. You should look at the temp anomalies for northwestern Australia for the past week. HOT!
What alternative measure would you suggest?
Gavin, we live in unusual times. But I like them. I like how amateurs have permission to question authority and can ask "detailed" (if stupid) questions. I think it says a lot about our society.
Still, it does get a bit odd at times… Why would anyone care if Gordon Robertson thinks Arthur Smith hasn't got enough qualifications?
Arthur P Smith "On the Earth, entropy increases."
delta Q = 0 because the incoming heat is balanced with outgoing so the heat content Q of the earth does not change the temperature does not change either
and what is our usual definition of entropy?
delta S = delta H/T if delta Q = 0 so does delta S i.e. entropy does not change in your model. I agree that entropy on real earth changes it increases and decreases exporting it to space with the heat. It's your model that is self inconsistent.
"it essentially implies isolation" the radiative equilibrium the comes with thermal equilibrium i.e Stewarts law which is simply a different way of stating Kirchoff's law is specificially does NOT imply isolation. Thermal equilibrium implies equal energy flux in both directions. If the only energy fluxes are radiative you only have Kirchoff's law operating.
I think the distinction between a steady state where the mean temperature over time is not changing and thermal equilibrium is one without any practical difference.
Thermal equilibrium might be a thorn in your side but it is definitely a symptom of the model on which you base your calculations so it must underlie the discussion.
"ou see the equations and assumptions in my paper – please state specifically which one you think is wrong"
Your equations are fine it's the parameters that you set for them being based on an inconsistent model that are wrong and one parameter in particular and that is the emissivity. If you used a consistent model with Kirchoff's law holding (as you in effect say it does in the par following eq 10) then the emissivity should be measured at the top of the atmosphere where the albedo is also measured and it too will be 1-albedo we have already discussed this at the climate audit bulletin board. The effective radiative temperature will not then be a black body 254 but a grey body 279 which actually reduces your greenhouse effect from 33K to ~9K.
So Jan why do radiometer measurements of downwelling longwave under cloud free conditions close to theory therefore exist?
Cohenite – don't let me divert you from being owned by Arthur but when you've said uncle here – http://bravenewclimate.com/2008/10/14/two-denialist-talking-points-quashed/#more-615
Your point Luke?
The radiometer readings and the the temperature readings actually show that the downward radiation is equal to the radiation absorbed by the atmosphere to quite a high degree of precision so what is your point exactly?
Jan Pompe – you say "I think the distinction between a steady state where the mean temperature over time is not changing and thermal equilibrium is one without any practical difference."
It has enormous difference to anybody who has studied the subject of thermodynamics – or even basic physics and chemistry. It is the difference between a stagnant pool of water (equilibrium), and a pool in the middle of a river (steady state). It is the difference between a chemical production line with steady reaction rate (steady state) and the same line turned off producing no net product (equilibrium). It is the difference between a jar of stale cookies that nobody wants to eat (equilibrium) and a jar that is steadily maintaining its level through a balance between baking and eating (steady state).
The difference is enormously significant, and the model in my paper is a steady-state model, *not* a thermal equilibrium model.
Entropy production happens at a steady rate in the model (and in the real Earth) through the conversion of 5000 K short-wave photons into thermalized 255 K long-wave photons. No, the additional entropy doesn't get added to the Earth itself (Earth is in a steady state), but it means it is available to drive all sorts of non-reversible processes. The entropy change is not in the Earth itself, it ends up in the radiation field that heads off into space; Earth interposes itself to convert low-entropy photons into high-entropy photons in a non-reversible manner. This is not thermal equilibrium.
You go on to say "the emissivity should be measured at the top of the atmosphere where the albedo is also measured and it too will be 1-albedo"
That depends on what you want to talk about – but if you insist on discussing the emissivity of the upper reaches of the atmosphere, then yes, it will be 1 – albedo – after you correct for the wavelength dependence of the albedo. At short wavelengths Earth's albedo is about 0.7. At long wavelengths it is close to 1 both on the surface and at the top of the atmosphere: clouds do not reflect infrared very well, nor does snow and ice, rather they absorb it. Once again, even when you do this at the same location, you get different numbers because they are physically distinct situations: short-wave vs. long-wave.
You say "The effective radiative temperature will not then be a black body 254 but a grey body 279" – No, it will still be 254 or 255. In fact that's what's measured – the Earth's photosphere (close to the tropopause) is at an average of roughly 255 K, nowhere near as high as 279 K. How do you explain that observations disagree with your claim?
cohenite – I guess I'll let you sleep on it. As far as I can tell, your discussion of inequalities between effective and average temperature is exactly what I describe in my article. If you have a uniform temperature across the planet, the effective radiating temperature and the average temperature are the same. If temperatures vary, as in Motl's example, then the average temperature drops, for a given effective radiating temperature. There is no way for T_ave to be found higher than T_eff just by redistributing energy around so some places are hotter than others – so how do you explain the fact that on Earth T_ave on the surface is that much higher than the T_eff you would expect based on the flux of incoming solar energy? That's the central question for anybody who doesn't believe in greenhouse warming.
"effective radiative equilibrium temperature Teff of Earth defined as the temperature of a blackbody with a total emission equal to the net solar radiation received by Earth averaged over its entire surface"
The atmosphere in no way shape or form can meaningfully be described as a blackbody. Atmospheric scientists should try some physics? T sub eff, applied here, is jive, an empty conceit.
Moreover, less than 50% of the energy even reaches the surface.
Correction – albedo is about 0.3 at short wavelengths, close to 0 at infrared. (or read what I wrote as referring to 1-albedo).
Gary (Oct 16, 1:39) – the Earth as a whole, at thermal wavelengths, is very close to a black body. The atmosphere alone is not, but only because there are some infrared wavelengths that pass straight through from the surface. Earth as a whole (including the atmosphere) looks black in infrared.
On the "less than 50% of the energy even reaches the surface" – first, we're already accounting for the 30% of incoming solar that is reflected away – that's the albedo issue Jan Pompe is so hung up on. Of the remaining 70% or 235 W/m^2, about 67 (29% of the 235) is absorbed by the atmosphere before it reaches the ground, which you could argue makes the actual value of T_eff for the surface even lower, leading to a greenhouse warming of not 33 K but about 54 K – however, in a hypothetical atmosphere with no GHG's but with short-wave absorption as we have now, the atmosphere would end up warming the surface due to that absorption, so the energy would end up getting to the surface anyway (just not directly through radiation). So a 255 K T_eff really is the best number for comparison.
Re my comment about the average voltage in an AC powerline being zero – it seems that many of you completely missed the point I was trying to make. Perhaps I should have said, "the average voltage at any point along a wire carrying AC is zero"
My point is: if, at a particular location, the temperature is 40C for 12 hours of the day and 0C for the other 12, the average temperature is 20C. If it's 21C for 12 hours and 19C for 12 hours, the average is still 20C. And if it's 60C for 8 hours and 0C for 16 hours, the average is still only 20C. The average temperature at a location tells you little or nothing about how hot or cold it gets at that location, and average global temperature even less so. And when you have nonlinear responses to temperature, or dependencies to temperature gradients, the picture is murkier still.
"Perhaps I should have said, "the average voltage at any point along a wire carrying AC is zero""
So how do we get to call it AC of a particular voltage, and how do we get power out of it?
For AC we already have two useful constructs, RMS and Peak to Peak. Both are useful measures of voltage, and can be averaged. Climate is no different, you just have to define a measurement that reflects a meaningful representation of what we are investigating.
RMS is important, it gives a means of defining the actual power being supplied, Peak to Peak is also important, you want to know your capacitors are up to the job.
Since STJ beat me to the RMS concept in AC power considerations while I was doing the weekly bins, let's go back to what's in the cookie jar in terms of our budgets here.
It's the oceans fellows! Too much emphasis on the atmosphere clouds your image of mother earth in terms of what's cooking down under. The balance between water and ice is the only measure you need long term.
SJT, you're also missing the point by miles. I do not need to be lectured on electricity, I was merely illustrating a point – that focusing on irrelevancies gets you nowhere.
As you have so very amply demonstrated. 🙂
luke; Arthur can't own me, you and NT, the double-headed ogre, already bought me from Deltoid.
Your link to Brooks features a temp and ENSO chart; ENSO seems to explain the temp variations and Christy has already explained the greater sensitivity of MSU data to temp extremes; but I'll read it after Arthur completely buries me and the last pathetic remnants of the valiant but doomed sceptics rag-tag army.
Gordon would be amused that despite all my experience with labs full of electronic test equipment I still use a light bulb at home to check torch batteries, AC power outlets and other bits and pieces that still bother me and despite the laws of averages I feel safe using about three of each to establish my routine each time.
Peter: I make relative measurements all the time. My current rain gauge is the old Daytek garden barrow with the galvanised top and a permanently flat rubber tyre. It's usually parked by the compost bins under the trees in case it rains. At the moment it's about one third full and if I don't wait for a windy day to blow it away, that's quite a useful amount of rain in a couple of days considering my barrow normally stays dry for months on end.
Any single point of measurement will do if we are only interested in our domestic environment. In fact where my tomatoes are concerned hiding from a possible frost in pots under those same trees, my barrow is more important than the BoM station out at the airport because most of their predecessors died from over exposure to the ravages recent drought. My barrow serves another purpose in averaging evaporation after artificial water sprinkling.
Cohenite; imo you were well warned.
gavin; I was being slightly ironic; Arthur, imo, still has a couple of issues; the main one is that he says the "fourth power of the surface temperature can exceed this limit… (by being) covered by an atmosphere that is at least partially opaque to infrared radiation." This temp, Tave, is dragged upwards by Teff being increased by the downward LW, Philipona's LDR; this LDR increases the SB energy available at the surface to be put back into the atmosphere and back again, and so on and so forth; the logarithmic decline is negated by, as Arthur states, "more than one absorbing layer" of CO2 (p9); this is a classic Weart semi-infinite, opaque atmosphere; it has been argued against by Miskolczi, and I am noting that the difference between Tave and Teff is an indication that "the total energy budget can be completely unaffected" even if, according to Arthur's measure of average global temperature, Tave, does increase; as Motl shows, if Tave increases by an amount less than the difference between Tave and Teff, then there need not be any increase in the global energy budget; by looking at only the global indices and not how the regional components of Tave are configured Arthur and the AGW model miss that crucial point.
Luke, it's nice to have Arthur here… Kind of refreshingly rational. At least no one is trying the ridiculous conspiracy theory nonsense…
IT'S THE MARXISTS!
Arthur P Smith "It has enormous difference to anybody who has studied the subject of thermodynamics – or even basic physics and chemistry."
Are you out to insult me? Well 2 can play that game. You seem to have a week spot in thermodynamics yourself and in systems theory, and if you were an engineer in my employ I would not be able to trust you to sort out a customer's temperature control problem I'd send a technician.
Now you talk about the average temperature of the troposphere at 254 K is the actual measured temperature not the temperature it would be without GHG. Don't you see the contradiction (absurdity) in that?
Imagine this "The average temperature of the heat sink is 105C those transistors should not be blowing up" yes well never mind that the junction temperature is getting up to well over 200C. You have proof that it isn't :- the average is 105. Ridiculous!
The pool in the middle of the river which you state as being in a steady state as opposed to being in equilibrium if the volume of water in that pool is not changing IT IS IN VOLUMETRIC EQUILIBRIUM the stagnant pool which is probably evaporating will be losing volume it may be in a steady state :- steadily losing volume i.e. dV/dt = constant thus not in equilibrium.
It's exactly the same with any object where radiative energy in = radiative en energy out it is in energy flow equilibrium the internal energy is not changing and its temperature is not changing therefore it is in thermal equilibrium. Kirchoff's law does NOT apply to an isolated system but one where energy is flowing in and out what you call steady state and I anyone else who has ever had to work with thermodynamics (not just study it) would call equilibrium when the two flow rates are equal.
"Once again, even when you do this at the same location, you get different numbers because they are physically distinct situations: short-wave vs. long-wave."
Oh really? KIrchoff's law cannot be affected by wavelength try not to mix classical with QM it leads to the confounding confusion that you are experiencing. If the energy content is not changing because the incoming energy flow rate is equal to the outward flow rate of an object it is in equilibrium and the wavelength is irrelevant to get right results just count the joules entering and leaving. If you were to suddenly isolate the object in that state the temperature will not change because the net flow which is zero does not change either.
If you take the measured (ERBE) average radiation out from the the earth of 235 W/m^2 divide it by the emissivity .7 ( .69 is closer but sticking to 1 significant digit)
we get 336. now dividing that by Stefans constant we get
5.92E9 and taking the fourth root we get the temperature a body with the same absorbance as emissivity = .7 needs to be to radiate the 235 W/m^2 and that is 277K which is within the ball park unlike you 254 or 255K.
It should not be surprising that this lowers the height of the height of the the characteristic temperature in the atmosphere to the top of the bulk of the absorption/emission limiting clouds at around 2.5 K.
Cohenite; I can simply avoid all the discussion about radiation this way and that including reflection, absorption, refraction etc way by setting my yardstick at the bottom of the pile. I always summed it up like a bucket of water with some large ice blocks. At the polar fringe where ST becomes a critical measure of the radiation balance we can easily track the annual movement by satellite. Elsewhere we can track the long term trend by sea level. One degree C rise in fifteen is a lot. No complicated science needed.
Back to the local environment, there is a consensus amongst rural producers that this drought is unprecedented and there is no respite looming. We could say my wheel barrow averages more rain drops than your typical clear plastic commercial model and the daily catch needs to be tipped into a household measuring jug for greater accuracy in calculations, however I'm only interested in amounts that will soften the soil and penetrate to greater depths over time.
Yes in this drought I can also dispense with drips too as the water table on this hill side has been way beyond reach for ages. There is a good crop of clover now on the back lawn but down under our big cedar out front the soil is as fine and dry as talc powder. I keep an eye on a particular iron bark that is shedding lots of blossom again. Big trees elsewhere continue to die.
But then Jan ruins the rational temperate discourse with rants like:
"You seem to have a week spot in thermodynamics yourself and in systems theory, and if you were an engineer in my employ I would not be able to trust you to sort out a customer's temperature control problem I'd send a technician. "
I mean gee, what a terrible insult. Arthur better change his mind or else he won;t get a job with Jan…. Yeah, that's really nasty Jan…
Jan, I found this on the net
"At equilibrium, the radiation emitted must equal the radiation absorbed. Therefore,
1 – emissitivity = R
where R is the reflectivity. The equation holds when the quantities are appropriately averaged over wavelength, but not necessarily at any given wavelength (incident visible light can be reradiated as infrared). "
I don't see how this matters in terms of what Arthur was saying…
Oh no… I wish I hadn't said that… Will you employ me? Please! PLEASE EMPLOY ME!
cohenite: "but I'll read it after Arthur completely buries me and the last pathetic remnants of the valiant but doomed sceptics rag-tag army."
That is not likely to happen because as more empirical work is done the less support there is for the hypothesis of AGW, positive feedback etc with no end in sight.
Sorry that accolade belongs to Arthur with his:
"It has enormous difference to anybody who has studied the subject of thermodynamics – or even basic physics and chemistry."
the implication should be obvious but perhaps too subtle for you.
"Will you employ me? Please! PLEASE EMPLOY ME!"
No chance you found something on the net you didn't understand and shot of your proverbial mouth.
NT; Arthur has saught to distinguish wavelength, not Jan; and Jan raises a valid point, which is, is the entire blackbody temp anomaly due to greenhouse; Arthur argues that it is; there are other points of view; and even if the greenhouse is responsible for the 33K anomaly, does that mean that the greenhouse will be increased as predicted by AGW.
And respect is a 2-way street; Jan is a knowledgeable guy; noone in this debate has the foresight of Janus; except maybe you and luke, who have 2 heads; so I guess you can afford to be cocky.
As I have said before, (and even dirty harry), a man has to know his limitations.
"Arthur argues that it is; there are other points of view; and even if the greenhouse is responsible for the 33K anomaly, does that mean that the greenhouse will be increased as predicted by AGW."
Finally, we are getting to the real debate.
SJT, we won't as Cohenite and Jan will fight tooth and nail to deny the existence of the Greenhouse Effect. Where did Louis and Graeme go??
Cohenite, I was replying to Jan's " KIrchoff's law cannot be affected by wavelength"
Kirchoff's law says it needs to be at equilibirum, didn't Arthur say he was working from "steady-state"? Did he not point out that this was not thermal equilibrium?
And this "so I guess you can afford to be cocky." I'm not cocky, I don't pretend to know more than I do Cohenite, and when wrong I will admit it.
Jan, "No chance you found something on the net you didn't understand and shot of your proverbial mouth."
I know I was pretty subtle but really…
Ok I'll spell it out. I was mocking you because your 'attack' was like being hit with a cold crumpet. Who cares if you don't want him to work for you?
You see, I was actually asking a question. I posted Kirchoff's Law, then asked why this is relevant to what Arthur was saying. No shooting of my mouth. You need to calm down a little. Try deep breathing.
The funny thing is the scientists who are sceptics, such as Michaels, Christy, Lindzen, all agree there is a greenhouse effect. They just disagree on the extent of warming.
SJT "As I have said before, (and even dirty harry), a man has to know his limitations."
Indeed and a PhD in particle physics does not really prepare one for systems identification which is actually where he is going wrong. He says he is dealing with two different systems but claiming a result as if it is one. This is a perfectly valid thing to do if done properly we do it in control system design all the time but ultimately the transfer function you arrive at must be a combination of it all.
For instance the atmospheric system (ignoring storage for the moment) can be seen as a potential divider with the centre at the surface in fact it is one. Now even if we can change only the impedance from surface to space and restrict the out going flux we also when we do this restrict the incoming flux because the systems are in series.
The mechanism for this is a small rise in potential at the centre of the divider but this rise will be less than it would be if the flow through (current) is unchanged.
In the climate system we really can't change the impedance to space without changing the impedance to incoming (except in our imaginative models) since the major player in these impedance changes is the cloud cover i.e a single body affecting both so impedance to incoming and outgoing are strongly coupled.
Gavin "Gordon would be amused that despite all my experience with labs full of electronic test equipment I still use a light bulb at home to check torch batteries…"
Heck…I use a trusty old incandescent 60 watter to test fibre optic cable. I strip the fibres on one end, do a quick cleave, tape them together and point them at the 60 watter. Down the other end, which could be several hundred metres away, I terminate the cable properly and look at it with a 100x magnifier. If I see a bright moon in a dark background, with the moon about 2/3ds of the darkness, I know I've got a good connection before testing it with an instrument.
Funny enough, I was looking at a fibre one day and the moon was about 1/3rd the dark ring (the cladding) around it. I scratched my head for a while, which did no good, and consulted the experts. They stood around scratching their heads. We brought in a TDR (time-domain reflectometer), which costs about US$10,000 and it told us the problem was in the last 25 feet of the cable. The only recourse was to strip the cable back to see what was happening.
About 10 feet down the cable, the glass fibres were twisted around each other like copper twisted pair. The manufacturer wouldn't believe me till I sent him a sample.
SJT & NT: "The funny thing is the scientists who are sceptics, such as Michaels, Christy, Lindzen, all agree there is a greenhouse effect. They just disagree on the extent of warming."
As usual the two emptiest vessels make the most noise. From an earlier comment of mine
"The effective radiative temperature will not then be a black body 254 but a grey body 279 which actually reduces your greenhouse effect from 33K to ~9K."
Do either of you interpret that as saying that there is no greenhouse effect? Perhaps you can provide a strawman translation as to how you arrive at the conclusion.
Jan: I reckon you should expand on your systems id then we can look at this
I'm not with your notion of an electric circuit here. Optics for light like transmissions please
Jan, how do you then explain the hot house world of the dinosaurs?
Jan, does Kirchoff's Law apply to Arthur's "Steady State"model – he said his model wasn't in Thermal Equilibrium, does that mean you don't use Kirchoff's Law?
Precisely my point there was a plunge instead of greater warming due to all that extra open water absorbing more heat and bringing it south to warm the globe.
Jan, so you are suggesting that the La Nina we experienced early this year is due to the melting of the Arctic? Well that IS intriquing.
Jan Pompe:
Jan, why do you divide the outgoing longwave flux (235 Wm^-2) by 0.7? This is the NET flux outgoing. You don't have to correct this figure by anything. The Teff is just the temperature of a blackbody corresponding to this radiative flux. Thus, Teff = (235/5.69*10^8)^0.25 = 253.5 K. This is the figure (actually, 253 K) tabulated as Teff, Table 3-1 in Goody and Walker, Atmospheres, the book I cited above.
NT: "does Kirchoff's Law apply to Arthur's "Steady State"model – he said his model wasn't in Thermal Equilibrium, does that mean you don't use Kirchoff's Law?"
In spite of what Arthur is saying his "Steady state" model is in equilibrium. If it's in equilibrium which is what constant temperature, constant entropy (the fact that the entropy of the radiation is increased on the way through is irrelevant to the earths entropy) imply and radiative balance imply then Kirchoff's law applies, even though Arthur would prefer it didn't.
Any system can be in a steady state and changing for instance the universe the only truly isolated system there is has a steadily increasing entropy so it's steady state is one of continuous increase is it in thermal equilibrium? I'll leave that one for the philosophers as it's not of practical concern. Stable oscillators also continually changing and are in a steady state. Steady state can mean unchanging but not necessarily. So equilibrium implies a steady state the reverse it not necessarily true.
Nt; you and Arthur should read this;
http://arxiv.org/ftp/arxiv/papers/0805/0805.1625.pdf
This thermal equlibrium and steady state difference is a bit of a red herring to this debate; Stewart's Law applies when a system is not in thermal equlibrium to the extent that if there is more absorption there will be more more emission. Kirchhoff's Law will apply when Stewart's Law has brought the system back to Equlibrium which is happening more or less instantaneously via variations in RH as per Miskolczi.
As to the dinosaurs; their hot-house is perfectly explicable in terms of Jan's comments about clouds;
http://www.sciencemag.org/cgi/content/abstract/320/5873/195
Jan, did you read Goody and Walker?
http://lasp.colorado.edu/~bagenal/3720/CLASS14/14EVM-5.html
They do the math here…
I'd like to hear your response to Peterd.
Cohenite, they still appeal to the regular greenhouse effect. Also note that their cloud formation isn't governed by RH, as I mentioned before cloud formation requires a lot more than just water in the air.
"constant entropy (the fact that the entropy of the radiation is increased on the way through is irrelevant to the earths entropy) imply and radiative balance imply then Kirchoff's law applies, even though Arthur would prefer it didn't."
I think your the one arguing with reality, not Arthur.
SJT "I think your the one arguing with reality, not Arthur."
Then perhaps you can show that a body that has a constant temperature (as Arthur's model does) and equal incoming and outgoing heat is not in thermal equilibrium.
Jan, Peterd asked you this question:
Care to respond?
Gavin…the entire point of my expose on alternating current was to draw attention to how mathematics can be abused in physics. I couldn't get my point across without explaining some basic theory. Even after that, some people are still talking about average voltages being zero at any point in a circuit. That is nonsense, and it's based on not understanding the physics.
One way of getting an average value for instantaneous values in a sine wave, is to integrate from 0 to 2 pi. If you don't take care of the negative sign in the second part of the sign wave, you will end up with a value of zero. To accept that, however, would be to reveal a misunderstanding of how electricity works, and that's why I am concerned about the number of mathematicians doing physics these days and being taken seriously.
Electric currents in industry and in residential usage are not sine waves per se. They are modeled by sine waves and phasors for convenience only. It's only because they are generated by a circulating machine (generator) with magnetic poles that the currents can be represented by a sine wave.
Anyone insisting that the average alternating voltage in a circuit is zero at any point in the circuit doesn't understand electrical theory. When we talk about voltage in electrical theory we are not talking about the entire sine wave from 0 to 2 pi, we are talking about the amplitude of the sine wave in one half of the sine wave only. The average voltage in an alternating source is 0.636 times the peak value of 'one' peak, not the peak-to-peak value, and not the integral from 0 to 2 pi.
It would be very easy for a mathematican to draw the conclusion that the average was 0 if he didn't understand the electrical theory. I am convinced the same problems are encountered in AGW theory. We have people applying physics to systems they don't understand.
NT; We can't have this radiative earth = a notional black body, can we? Well blow me old math and try again hey
Gordon; when I look at a decent global temperature chart, I can look underneath the troughs, or look above the peaks, perhaps up the middle too, and see the same trend. It's a hockey stick despite all the averaging techniques employed to smooth the original data. In coming to that conclusion I first have to trust the publisher however I can easily verify it by simply listening to the local birds or watching the older trees.
IMO Electrical engineers like instrument engineers and radio engineers need to be very good at the theory and the practice of each discipline but the math can be common despite the medium. The same goes for other disciplines except for law and accountancy it seems. Avoiding their big swings is how I survived.
What we need to do here is examine climate for big swings by whatever means we have available and ignore those other blowflies while we work. The trick I used a lot in industry was tread quietly and listen. That way we can learn something from just about everybody on the job.
Peter: "The Teff is just the temperature of a blackbody corresponding to this radiative flux."
"The Teff is just the temperature of a blackbody corresponding to this radiative flux."
The earth + atmosphere is NOT a black body. The 235 is the net outgoing flux of an effective grey body whose effective emissivity is ~.69 the same as its absorptivity. The equilibrium temperature (and the system is in equilibrium in the model) is then 278.
You want to calculate the black or grey body equilibrium temperature (it's actually the same due to Kirchoff's law) use
Te= sqrt[r(s)/2R(orbit)]*Ts
Te = earth's equilibrium temperature r = sun's radius R radius of earths orbit & Ts = surface temperature of the sun.
I've written the derivation here:
http://www.climateaudit.org/phpBB3/viewtopic.php?f=4&t=6&st=0&sk=t&sd=a&start=110#p618
SJT: "Care to respond?"
Yes now where is your response to:
Jan; so, is the greenhouse effect 288-278/277 = 11-10K; or 277/278-255 =22/23K?
SJT re 1% of GHG's warming atmosphere by 33 C. "It all escapes in the end. It's a matter of the rate it escapes at".
I looked at both your links, having to hold my nose while looking at Wikipedia. Neither one explained how GHGs as rare as H2O and CO2 can warm the planet by 33 C.
Here's G&T on that: "Global climatologists claim that the Earth's natural greenhouse effect keeps the Earth 33 C warmer than it would be without the trace gases in the atmosphere. 80 percent of this warming is attributed to water vapor and 20 percent to the 0.03 volume percent CO2. If such an extreme effect existed, it would show up even in a laboratory experiment involving concentrated CO2 as a thermal conductivity anomaly. It would be manifest itself as a new kind of `superinsulation' violating the conventional heat conduction equation. However, for CO2 such anomalous heat transport properties never have been observed".
The effect of warming attributed to the H2O/CO2 ratio varies from the 97/3% of Lindzen to the 75/25% of Schmidt, who differentiates between water vapour and clouds.
G&T have offered 80/20%. The question still arises as to how a gas that accounts for 3/100ths of atmospheric gas can contribute 20 to 25% of global warming while helping raise the planet's temperarture by 33 C. It boggles the mind further to consider that anthropogenic CO2 is 3% of the 3/100ths % of atmospheric gases.
Why are we even talking about this? Are there figures anywhere that show how this is possible, or are we going on the word of mathematicians programing GCMs?
Jan, so the emissivity of the Earth + atmosphere = 0.69?
So the temp you calculate is for the tropopause?
You know what is interesting?
the figures that are traditionally used to describe the Greenhouse Effect such as in this page:
Actually show the same numbers as you describe, with 69% outgoing IR and 235 W/m2 etc. So, why do you end up with a te so much higher? Is it because your temp is for a point in the atmosphere, and not on the surface?
Jan, you confuse me with SJT.
gavin "What we need to do here is examine climate for big swings by whatever means we have available…"
The only means I can see right now are satellites. Spencer has told us the MSU units are not sensitive enough to detect IR from the surface, so where are all the numbers coming from upon which the greenhouse theory is built? I have no problem with it as a theory, I do have an issue with the confidence expressed in climate models and theoretical calculations. But your right, we should be observing and improving our observational capabilities rather than rushing off to conclusions based on models.
Because it doesn't meet the criteria for "thermal equilibrium", as per the scientific definition. For one thing, as Arthur pointed out, entropy is changing. Like I said, if we can't agree on the language and defintions, the whole exercise is a waste of time.
http://en.wikipedia.org/wiki/Thermodynamic_equilibrium
The earth and sun don't meet that defintion.
Jan, so the Earth only radiates back 69% of the energy it receives? What happens to the other 31%? This doesn't seem correct, why would the Earth lose 31% of the energy it receives? Where does it go?
cohenite: "As to the dinosaurs; their hot-house is perfectly explicable in terms of Jan's comments about clouds;"
Thanks for that and the link. It really wasn't and isn't an issue the dinosaurs would be perfectly happy in Indonesia today. In fact one rather small one (the Komodo dragon) is still in residence there. The state and nature of the world that far back in time is subject of great uncertainty and I for one wouldn't like to hazard any guesses. Finally it's just another red herring that abounds around here.
SJT; "What happens to the other 31%?"
Albedo it's not absorbed in the first place.
Jan, Komodo dragons aren't dinosaurs.
Jan that link appeals to the Greenhouse Effect.
Jan, in your grey body calc, what is the surface temp? You have calculated the temp at some point in the atmosphere, yes?
I am NT…
Ok, so why is it factored twice (once coming in and once going out).
I can see the fundamental disagreement you are having with Arthur rests in this:
Arthur:
"In particular, they are strongly reflected by clouds, snow, and ice, while the longer wavelength radiation from Earth is strongly absorbed by all three; this accounts for the difference between the 0.7 emissivity at short wavelengths and 1.0 at long."
Jan:"the net outgoing flux of an effective grey body whose effective emissivity is ~.69 the same as its absorptivity"
So Arthur is saying that the emissivity depends on the wavelength and you are saying it is independent of wavelength.
Is that right?
Which is not the case here 🙂
No, I am NT!
NT; get a grip; the 31% is Albedo; your own link shows that.
Jan, I think I have worked it out. It's not that the emissivity changes, it's that the albedo is not a factor anymore. The only reason there is a 0.69 absorptivity is due to the reflection by clouds and ice etc. But these don't operate the same on the way out, otherwise you'd have to account for radiation reflected back at the surface from the undersides of clouds.
Cohenite.
what I am struggling with is that due to Albedo we have 69% of the incoming radiation absorbed. But what Jan seems to be suggesting is that only 69% of the that absorbed radiation is then emitted.
I am not pretending to know what I am talking. I am just attempting to understand it.
Here is the actual bone of contention it seems:
SJT; "The only reason there is a 0.69 absorptivity is due to the reflection by clouds and ice etc. But these don't operate the same on the way out, otherwise you'd have to account for radiation reflected back at the surface from the undersides of clouds."
The actual microphysical process may differ but the macrophysical effects end up being the same. If you try to do an accounting all the difference effects from clouds that include reflection, scattering absorption/re-missions and the continual flux between particulate and vapour and the emission/absorption it's quite unlikely that you will be able to effectively model it. It's best just to go above it all and measure there it and take Kirchoff's law into account.
Jan, you said "If you take the measured (ERBE) average radiation out from the the earth of 235 W/m^2 divide it by the emissivity .7 ( .69 is closer but sticking to 1 significant digit) we get 336. "
But, in the diagrams I posted before it showed that 235 W/m2 = 69% of the radiation. Haven't they already taken the emissivity into account? The 235W/m2 is a measure of the 69% emissivity.
It would appear that you have used the emissivity factor twice.
NT/SJT?Luke says
Janet, you have used you emissivity twice
NT/SJT/Luke says
Jane do you agree that the difference between you and arthur is as I suggested?
No, I am Spartacus!
NT; read the rest of Jan's calculations; the 336 needs to have SB apllied to it to translate it into the greenhouse effect according to Arthur's model; on the basis of that further calculation the average temp, Tave, is 277K; which gives a greenhouse per Arthur's model of either 288-277=11K, or 277-255=22K; I hope I'm not verballing Jan here, but in any event, I think either figure is too high because they would need to be moderated by the difference between Tave and Teff, as calculated bY Motl's method, which, for gavin's benefit, I should point out is consistent with Pielke's peer reviewed paper I referred to previously.
Cohenite, I read his calcs. It's the figure of 336 that bothers me.
Why does he multiply the net Flux of 235 out by 0.69. The net flux already takes into account the emissivity of 0.69.
Jan: "If you try to do an accounting all the difference effects from clouds that include reflection, scattering absorption/re-missions and the continual flux between particulate and vapour and the emission/absorption it's quite unlikely that you will be able to effectively model it"
Isn't this where we need a man with a Phd in particle physics?
Cohenite: no, you are mistaken. The greenhouse effect under discussion is the difference between the temperature the earth's surface would have if it were at the temperature of a blackbody radiating at the 235 W/m^2 we see for the actual outgoing radiation- this is shown to be 253-254K- and the actual temperature we see at Earth's surface (~287K). This difference is about 33K. If you doubt this, I can only refer you to a discussion in the pages of Physics Today, back around 1993-4, where no less a person than Richard Lindzen did not take issue with the 33 K figure. Note that the earth's surface (as distinct from its atmosphere) is very close to black-body in nature. As Arthur Smith noted, the atmosphere is different, having significant windows in the i.r., which allow i.r. out to space. Supposedly (I'm not taking sides here), the "closing" of these windows by GHGs is what reduces the i.r. losses to space and constitutes the enhanced greenhouse effect.
peterd; you misunderstand what I said; the temp difference is 33K; what I was saying is that the greenhouse is responsible for either 11 or 22K of that; as well, as I understand the terminology, "enhanced greenhouse" is not just the absorption of IR by CO2, which is the greenhouse, but the +ve reinforcement of that by feedback from water; neither have occurred according to the empirical measurements, despite IPCC predictions of a 3C increase for a doubling of CO2.
Sorry, of course I meant why does he divide the net flux by 0.69
NT: "Jan seems to be suggesting is that only 69% of the that absorbed radiation is then emitted."
Not quite the two processes are effectively in series like two resistors with a voltage across them the equivalent to voltage is the temperature difference the radiation is equivalent to current. So the actual flux through the system if you want to go down to microphysical processes and probably drive yourself mad in the process (you really ought to take a look at attempts to prove Kirchoff's law you'll see what I mean) the effect of the atmosphere (clouds too) on incoming is just as complex as they are on outgoing. The upshot is that in a model like Arthur's where there is no thermal inertia taken into account the (planet is in thermal equilibrium at t=0) the absorbance and emittance are not separable processes and we can actually represent the system as a single potential (like the equilibrium temperature) and a single impedance comprised of the input and output impedance in parallel.
I hope I haven't confused you more.
Gordon Robertson: you are having trouble understanding how water vapour and CO2 can cause so much trouble, compared to the much more abundant nitrogen and oxygen (& argon). All molecules are not created equal & these last three (including monatomic argon) are not appreciable infrared absorbers. Water vapour and CO2 both have strong absorption bands in the infrared. How significant these are, in terms of "greenhouse effect", comes down to how much of the outgoing longwave radiation (which, being in the infrared and peaked around 15 microns) can be absorbed by the GHGs. This depends on the concentrations of the gases and the positions of their bands relative to the energy distribution of the atmospheric i.r. radiation. I don't have time to run through back-of-envelope calculations now, but there are internet calculators that allow you to calculate the total fractions of the upward BB energy emitted within certain spectral intervals, from which (making assumptions as to the widths of the bands and the concentrations) you can estimate the fraction of i.r. absorbed. You might be surprised at how much energy can be absorbed by gases present only at parts per million levels.
Cohenite, Jan needs to explain why he divides the outgoing flux by 0.69
It's a strange step as the measured outgoing flux already accounts for the emissivity of the Earth
Cohenite; a great deal of modelling depends on your perspective in relation to where the action is.
Try thinking about our microwave networks and the various users for a moment; nobody owns the either but it is full of man made traps and getting noisier by the minute. Eventually we get traffic jams without the help of CO2. Finding communication signals in this form of radiation becomes quite a challenge. One part of the art is recognising phase and polarity, another is knowing what is salvageable in theory from practice.
Jan, I realised what you are doing a few comments back.
Here:Why does you divide the net Flux of 235 by 0.69. The net flux already takes into account the emissivity of 0.69.
Cohenite:
peterd; "greenhouse is responsible for either 11 or 22K of that";
So, is it 11 OR 22 K? And what is responsible for the other 22 (or 11) K?
So, are we agreed about Jan's mis-calculation?
You may be right about the enhanced greenhouse effect also including feedbacks. However, I dispute your claim that "neither have occurred according to the empirical measurements" (are there non-empirical measurements?).
Obviously, however, as you have so much time to debate all these issues (someone less charitable than I might suggest perhaps too much time), I will be going home and leaving you to it.
Goodnight.
NT; if an emissivity of .7 produces a net radiation of 235W/m^2 how else do you get the SB temp which produces that radiation; this figure of 277K is Teff not Tave as I said earlier. Why don't you plug 277 into eqn 12 of Arthur's paper to get Tave?
gavin: "Isn't this where we need a man with a Phd in particle physics?"
wouldn't know why I have done a bit of that as an undergraduate though nowhere near the depth that Arthur has I don't find it particularly helpful. I'd even go so far as to say it might it would tend to make it all the more confusing especially if you mix it up and work with bulk parameters for incoming and microphysical for out going. Worse still is ignoring the bulk parameters for out going because the microphysical is too complicated.
Well, good night peterd, someone less charitable than me might not bid you good night, but not me; I don't think it's Jan's miscalculation; the figures of either 11 or 22K apply to Arthur's model of greenhouse.
NT "Why does he multiply the net Flux of 235 out by 0.69
I don't I divide it. Then I divide it by SB constant and take the 4th root to obtain the grey body temperature the object has to be to radiate 235W/m^2 with an emissivity of .69. I actually used .7 (i had no calculator handy .69 yields a temperature of 278.3.
Going shopping now. Tata.
Jan's work doesn't agree with this:
http:lasp.colorado.edu/~bagenal/3720/CLASS14/14EVM-5.html
Look at the way they calculate the Teff.
They don't ramp up the 235 by dividing by the emissivity.
They sketch it here:
http:lasp.colorado.edu/~bagenal/3720/CLASS14/RadModel.jpg
And interestingly enough Wiki doesn't agree with him either:
http:en.wikipedia.org/wiki/Stefan-Boltzmann_law#Temperature_of_the_Earth
Read it all, you see that they calculate the Earth as having Teff of 179 BUT when you consider the 30% albedo it reduces to 255…
And the ref for that is:^ Frank Kreith (2000). The CRC Handbook of Thermal Engineering. CRC Press/Springer. ISBN 3540663495.
No less than an Engineering Handbook…
Jan, I actually corrected that a line or two down.
Oops typo above, SHould read that "Read it all, you see that they calculate the Earth as having Teff of 179 BUT when you consider the 30% albedo it reduces to 255…"
ARRGH !! typo above, SHould read that "Read it all, you see that they calculate the Earth as having Teff of 279 BUT when you consider the 30% albedo it reduces to 255…"
Cohenite it actually explains it even better here:
http:en.wikipedia.org/wiki/Black_body#Assumptions
Jan made an error by dividing the emitted radiation by 0.69 – there was no need to do that.
NT; the 235W/m^2 comes from a temp of 288 not 255, so the SB calculation for the blackbody IR flux (to use the colorado terminology) has to be divided by .7 to take into account the loss of Albedo and satisfy Kirchhoff (absorbance = emission). Otherwise you are doing a double deduction. The only issue is, is the greenhouse 11 or 22K?
Cohenite, did you read the wiki links I sent.
They outline the correct method
NT; the Wiki Black Body one; they establish a black body temp for Earth of 255K; Earth is a grey body with a Tg (per Colorado link) of 288K; this is the referable temp for calculation of the temp necessary to produce an exit fig of 235W, with an albedo of ~ 30%; you have to divide 235 by .7.
SJT: "http:en.wikipedia.org/wiki/Black_body#Assumptions"
Here is a reason why students get failed it they use wikipedia as a text book. They make the same mistake Arthur does (perhaps he plagiarised the page;-) the earth + atmosphere does NOT radiate as a black body. Secondly is a mistake they assume the earth is in thermal equilibrium so does Arthur but he does not like to admit it.
Jan, did you read it?
Cohenite, did you read it?
Jan wiki is sourcing: Frank Kreith (2000). The CRC Handbook of Thermal Engineering. CRC Press/Springer. ISBN 3540663495.
Jan your 279 figure is what they get if the Earth was a Black Body…
They get 255 here: http:eesc.columbia.edu/courses/ees/climate/lectures/radiation/index.html
http:www.geology.iastate.edu/gccourse/chem/evol/evol_lecture_new.html
http:dematerialism.net/Earth%20Part%201.html
http:www.physicsforums.com/showthread.php?t=172161
http://books.google.com.au/books?id=HnyPP4B4n-4C&pg=PA381&lpg=PA381&dq=effective+temperature+Earth&source=web&ots=JZHjvVKhOm&sig=ayhcwfPxhW-bx_Z7Sfkqv3oidYs&hl=en&sa=X&oi=book_result&resnum=2&ct=result
Heck just google "Effective Temperature Earth"
The problem is that it's not just a simple division by the emissivity.
See Jan,
this equation:
is a first approximation for a Black Body. That gives you your 279.
To incorporate albedo you need another term a.
Te= sqrt[{sqrt(1-a) r(s)}/2R(orbit)]*Ts
When you use a =0.3 you get Te = 255.
SJT: you cannot incorporate a non zero albedo with an emissivity of 1 and have thermal equilibrium. It's impossible. Why on earth do think Arthur fought so hard to deny the earth was in thermal equilibrium? If you go through his response you will see that he agrees that at TOA the emissivity of earth is not 1. You can check for yourself on MODTRAN that at 70 km (where it is set when you load ) that radiation up there is not balck body radiation. I don't he's quite silly enough to suggest that it is.
is a first approximation for a Black Body.
If you use this you get 279. That's what you got. All you did before was remove the 'grey body' effect of the Earth and calculate it's Black Body radiation.
And why do you keep calling me SJT?
Did you look at this equation?
SJT BTW the derivation I gave on CA BB also came from a Thermal engineering handbook which I no longer have but it's there in the Schaum's series of heat transfer exercises. I'll match your two books Kirchoffs law against your 1 with a wikipedia that violate Kirchoffs law any day 😛
yes I looked at the equation how do you think I know he sets the emissivity to 1?
Jane,
I think your derivation is wrong and I think most other physcists agree. The only Teff;'s I can find for the Earth are :
279 for a Black Body
255 for a Grey Body.
Jane, you made made an error.
No,
The emissivity in this equation is sqrt(sqrt(1-a))
SJT" "Te= sqrt[{sqrt(1-a) r(s)}/2R(orbit)]*Ts
What makes you think that? Where it's place in the equation makes it the 4th root of absorptivity.
SJT: You suggested google "Effective temperature earth"
Sorry but if you are talking thermal equilibrium then you want the equilibrium temperature it the temperature the earth will have when it is not changing. The effective temperature is the temperature a black body will have when it radiates at the same rate as a grey body for that grey body the equilibrium temperature is the temperature it is itself to get the same radiation as it is absorbing that is when the net flux is zero. Does this clear up your confusion?
You didn't read those Wiki posts I linked did you Jane,
It clearly shows the derivation.
Jane, you got it wrong. Have you found any other link that shows your derivation is correct? I cannot find one.
This probably won't work but:
To begin, we use the Stefan–Boltzmann law to find the total power (energy/second) the Sun is emitting:
The Earth only has an absorbing area equal to a two dimensional circle, rather than the surface of a sphere.
P_{S emt} = \left( \sigma T_{S}^4 \right) \left( 4 \pi R_{S}^2 \right) \qquad \qquad (1)
\sigma \, is the Stefan–boltzmann constant,
T_S \, is the surface temperature of the Sun, and
R_S \, is the radius of the Sun.
The Sun emits that power equally in all directions. Because of this, the Earth is hit with only a tiny fraction of it. This is the power from the Sun that the Earth absorbs:
P_{E abs} = P_{S emt} (1-\alpha) \left( \frac{\pi R_{E}^2}{4 \pi D^2} \right) \qquad \qquad (2)
R_{E} \, is the radius of the Earth and
D \, is the distance between the Sun and the Earth.
\alpha \ is the albedo of Earth.
Even though the earth only absorbs as a circular area πR2, it emits equally in all directions as a sphere:
P_{E emt} = \left( \sigma T_{E}^4 \right) \left( 4 \pi R_{E}^2 \right) \qquad \qquad (3)
where TE is the black body temperature of the earth.
Now, in the first assumption the earth is in thermal equilibrium, so the power absorbed must equal the power emitted:
P_{E abs} = P_{E emt}\,
So plug in equations 1, 2, and 3 into this and we get
\left( \sigma T_{S}^4 \right) \left( 4 \pi R_{S}^2 \right) (1-\alpha) \left( \frac{\pi R_{E}^2}{4 \pi D^2} \right) = \left( \sigma T_{E}^4 \right) \left( 4 \pi R_{E}^2 \right).\,
Many factors cancel from both sides and this equation can be greatly simplified.
I bloody hope so.
Suzie "Many factors cancel from both sides and this equation can be greatly simplified."
and the emissivity set to one and absorptivity to 1-A where A~.3 thus violating kirchoffs law.
Jan I googled as you suggested and still get 255 for Teff.
http:ocw.mit.edu/NR/rdonlyres/Architecture/4-401Spring-2006/13FD5F04-124D-489C-A452-C5BA99356AE4/0/hw1.pdf
http:www.marathon.uwc.edu/geography/100/rad-temp.htm
http:apollo.lsc.vsc.edu/classes/met130/notes/chapter2/te_earth.html
Where did you get your derivation from?
This page shows the (1-A) ^1/4
http:lasp.colorado.edu/~bagenal/3720/CLASS6/6EquilibriumTemp.html
You have got it wrong Jan.
Seems everyone else thinks your wrong jan…
Maybe you should check on your working?
Jan, where was emissivity set to 1?
Think it through. If you have a black body in space the same distance as Earth from the Sun you use this formula:
If you put in the sun's radius, temp etc. You get a Te of 279.
If the Earth was a Black Body in thermal equilibrium it would have a Te of 279.
Now we know it's not a Black Body, so it must have a Te less than that…
If you read the Wiki page, you could go through the derivation. It's actually not that complicated.
This is the simplification:
T_{S}\sqrt{\frac{\sqrt{1-\alpha}R_{S}}{2 D}} = T_{E}
T_S \, is the surface temperature of the Sun,
R_S \, is the radius of the Sun,
D \, is the distance between the Sun and the Earth, – α is the albedo of the Earth, and
T_E \, is the blackbody temperature of the Earth.
And if you simplify this equation out, you get the ones I showed above…
http:en.wikipedia.org/wiki/Thermal_equilibrium#endnote_Barbieri2007
Seems there is a lot about that gives the same result…
NT Teff != Teq get it ? and that google was your suggestion not mine. I initially thought it was SJT.
Teff is the the temperature the earth would be if it was a black body and in this case radiating 235 W/m^2. It is not the equilibrium temperature the temperature it would be at equilibrium when emissivity = absorptivity and the temperature is not changing because emittance = absorbance.
The only person that you are confusing is yourself I've lived with this stuff along time now I confident of my understanding of it. you on the other hand can't even figure out how I can tell the emissivity is set to 1 in those equations you are a so physically and mathematically
challenged. The derivation is a standard one from before the popularity of the IPCC nonsense became so popular among certain sections of the scientific community.
In that derivation you post you have the same contradiction
"Now, in the first assumption the earth is in thermal equilibrium, so the power absorbed must equal the power emitted"
and absorptivity = 1-A with A != 0 and emissivity set to 1 violating Kirchoff's law.
NT "Now we know it's not a Black Body, so it must have a Te less than that…"
No the equilibrium temperature is the same for a black body as for a grey body.
Well Jan, you may be confident with it and happy with your understanding, but everywhere I look I see the other result. So I am left with a choice. Do I believe you or every other derivation of equilibrium temp… It's not a hard choice.
"The derivation is a standard one from before the popularity of the IPCC nonsense became so popular among certain sections of the scientific community."
Where does this exist except in your own mind? Where is it?
Jan, but we know that Te=279 is the MOST it can be. The Earth will be less, it has to be, it reflects some of the incoming energy away. How can it have a Te=279 when it reflects 30% of the energy away?
It's in the Schaum's Heat and Thermodynamics by Michael Sprackling it was also in the text I had as an undergrad but lent to someone I haven't seen for a quite a while.
This by the way is not advanced stuff but really just for beginners.
Please your self though but I do suggest that you actually settle down and learn something go back over the posts that Arthur did not dispute that the emissivity <1 above the clouds and justified using different surfaces to reckon the absorptivity and emissivity by denying that the earth was in thermal equilibrium something which everyone of those texts explicitly assumes. They also assume that the absorptivity ~.7 and emissivity = 1 something that does not happen according to kirchoff's law (on which Planck's law is based) cannot happen for a body in themal equilibrium. Once you can actually understand that which you obviously don't you'll get a handle on it.
NT "Seems there is a lot about that gives the same result…"
Yes they all assume an absorptivity of 1-A where A!=0 and an emissivity of 1 which contradicts their initial assumption that the earth is in thermal equilibrium.
"How can it have a Te=279 when it reflects 30% of the energy away?
That is the temperature you get when it is in equilibrium the temperature rises until it emits what it absorbs i.e. until it reaches equilibrium ( I know it's hard to get the head around initially but it's not that bad I seem to remember having some similar difficulties with it so long ago) until it gets to equilibrium temperature it radiates, according to it's lower than equilibrium temperature, so emittance < absorbance. If the body is hotter of course it will emit more than it absorbs until once again it will reach its equilibrium temperature. It's effective temperature will then be <= its equilibrium temperature. Teff <= Teq and Teff = Teq only for a black body not a grey one.
Jan, I never said I knew what I was talking about. But no one seems to agree with you. There is nothing I can find that agrees with what you are saying.
I find a lot saying that the Black Body equilibrium temp is 279 and then they add that the Earth has a teff of 255.
"The real Earth does not have this "grey-body" property. The terrestrial albedo is such that about 30% of incident solar radiation is reflected back into space; taking the reduced energy from the sun into account and computing the temperature of a black-body radiator that would emit that much energy back into space yields an "effective temperature", consistent with the definition of that concept, of about 255 K.[3]"
So either you are mistaken or the internet is wrong.
Thanks Jan, I understand how you can have a Tequilibrium of 279.
NT; so let's clarify your lengthy dissertation;
255K = Black body; absorption =1, emission =1, albedo = ~.3
277(9)K =BB; absorption = 1, emission =1, albedo = 0
288K = ?
I think Jan your problem lies with the grey body assumption. Namely that emissivity=absorptivity.
Go to p90 of thie book: Measurements in Heat Transfer
By Ernst Rudolf Georg Eckert
It would seem that this assumption only holds when both the incident and emitted radiation are confined to the same wavelength.
Quoting:
"However, if the wavelength ranges corresponding to the incident and emitted radiation are different (e.g. Infrared and Visible), serious error may result if grey-body conditions are assumed."
this is the link I used:
http://books.google.com.au/books?id=bJCyau6CneMC&pg=PA90&lpg=PA90&dq=grey+body+assumption&source=web&ots=U7ZqyxHYhc&sig=bDktgNs1qmWqLzPlKKRieKUVwN4&hl=en&sa=X&oi=book_result&resnum=10&ct=result
NT you are most welcome I remember having difficulty with it too I figured I could afford you some patience.
cohenite: 255 is the effective temperature that is the temperature a black body will be if radiating 235W/m^2.
279K is the equilibrium temperature (greenhouse effect free) which the grey body earth will be when radiating *and* absorbing 235W/m^2.
288K is the "standard" global average surface temperature the difference between this and 279 = 9K is IMO the greenhouse effect.
In the opinion of others the difference between this and Teff=255 = 33K is the greenhouse effect.
The true figure is probably somewhere between all these figures but I wouldn't taking an average of all the opinions and saying that is the true number any time soon. That would be to place to strange a twist on consensus.
Cohenite, if you started at the top and worked through you'd probably get confused. I always said I didn't know what I was talking about… That being said I think I have discovered why Jan's work was not matching other work, it revolves around his adherence to the grey body assumption, which apparently doesn't always hold.
255k is the Teff of the Earth (accounting for albedo)
279k is the Tequilibrium of the Earth (Black Body)
288k is the Tequilibrium of the Earth (weighted emissivity? Or something – apparently it is calculated average temp assuming homogeneity)
Jan, I don't often mean ill (and generally it's pretty obvious as I just poke fun). I am actually trying to learn here, and I think that debating with people who think the opposite is the best way. They won't just agree if I am on the 'right track'. But it doesn;t mean I won't attempt to prove you wrong. Because I think you have made a mistake.
Jan, said it better Cohenite. But he needs to check his grey-body assumption.
From that same book:
http://books.google.com.au/books?id=bJCyau6CneMC&pg=PA90&lpg=PA90&dq=grey+body+assumption&source=web&ots=U7ZqyxHYhc&sig=bDktgNs1qmWqLzPlKKRieKUVwN4&hl=en&sa=X&oi=book_result&resnum=10&ct=result#PPA103,M1
"It has already been noted that the grey-body model approaches reality when the radiant energy participating in the interchange is confined to a limited range of wavelengths within which the spectral emittance is essentially uniform. The grey-body model becomes prone to significant error when the radiant energy spans a wide wavelength range that encompasses the visible as well as the infrared. Such a situation may occur, for example, when a surface emits infrared radiation and is simultaneously irradiated from a high temperature source such as the sun. The grey-body assumption also becomes tenuous when the range of active wavelengths contains strong emission (or absorption) bands."
NT "But he needs to check his grey-body assumption."
What assumption is that that earth is a grey body?
It isn't. It's a coloured and fluorescent body. Grey body is just an approximation that generally works pretty well. We can still obtain a "grey body" equivalent value by doing a line by line integration of the spectrum.
If you read above you can see that your grey body assumption that Emissivity=absorptivity doesn't hold
Here are some Engineers not using your emissivity=absorptivity
http:www.btinternet.com/~robertjtucker/gas_emissivity.htm
"The calculation of thermal radiation exchange in furnaces is simplified if the combustion product atmosphere can be assumed to be a grey gas. However, this assumption is a considerable departure from reality and can lead to errors in calculation. It is possible to represent the real furnace atmosphere by a weighted sum of grey gases plus a clear gas. This is often called 'the mixed grey-gas model'. This model retains some of the simplicity of the grey gas assumption but enables real furnace atmospheres to be more accurately modelled. "
I'll post this whole post again as you seem to have missed it.
Fun discussion, but I don't think I have anything to add beyond what I've said already, except to respond to one item:
Jan Pompe said (Oct 16, 1:46 pm): "perhaps you can show that a body that has a constant temperature […] and equal incoming and outgoing heat is not in thermal equilibrium."
There are many examples of nonequilibrium bodies that meet that condition. Yours, or mine, for example. The living human body maintains a constant internal temperature of 37 degrees C. Caloric intake and output is very close to being balanced, on a weekly r longer basis. But the only human bodies that are approaching thermal equilibrium are deceased, not living. "Equilibrium is death", as Henry Adams once said.
There's a good discussion of the difference between steady state and chemical equilibrium (the chemical analog of thermal equilibrium, where it is the flux of molecules rather than energy that matters) at "wikianswers":
http://wiki.answers.com/Q/What_the_difference_between_%27steady_state%27_and_%27equilibrium%27
"Far from being synonyms, the difference between steady state and equilibrium is the difference between life and death."
Gordon Robertson: "It would be very easy for a mathematican to draw the conclusion that the average was 0 if he didn't understand the electrical theory. I am convinced the same problems are encountered in AGW theory. We have people applying physics to systems they don't understand."
Gordon, that's precisely the point I was trying to make. You appear to have misunderstood my motivation.
I only said the average voltage was zero in order to illustrate the absurdity of applying mathematics to a physical process you don't understand.
A mathematician knowing nothing about electricity would maybe measure discrete points along the 'scope trace, take the average, and wrongly conclude that the average voltage is zero. That's completely wrong. You know it, I know it, but the mathematician doesn't.
My point was, many people make the same kind of fundamentally flawed assumptions when it comes to calculating and using average temperatures, without understanding if and how they fit in with the physical systems.
Even 'average' temperatures may not be what they seem. At many weather stations around the world, they simply take the maximum and minimum temperatures over a period, and then assume that the average temperature is halfway between the two. This may be true for some of the time, but it can be significantly wrong for a lot of the time. For example, if the wind changes and blows in some warmer air – like from a fire, an AC unit or a jet exhaust – the maximum measured temperature might move up and consequently the average, without the actual average having changed at all.
"There are many examples of nonequilibrium bodies that meet that condition. Yours, or mine, for example. "
Your body might, mine doesn't I radiate more than I absorb, and if there is too much heat about that I absorb more than is comfortable I try a little evaporative cooling. Reptiles absorb more than they radiate when warming themselves in the sun they are very efficient energy managers.
Arthur there is a world of difference between an internally powered and regulated system maintaining a constant temperature and one that passively sits there receiving heat until it's the same temperature as the effective temperature of the heat source. That is why I was always careful to mention the radiative balance as well as the constant temperature.
From the page you linked:
"equilibrium is a special case of a steady state"
I think I made that point above.
As crucial as it is let's leave the black/body/grey/body 255/279C difference, and look at the 288C figure; that is the global average temp; I have already referred to the papers by Essex and, in particular Pielke, and the Motl piece; in the first instance these works attack the idea that the enhanced greenhouse, the addition of CO2, will increase the energy budget; the difference between Tave and Teff establish that that need not be the case; but I also think they undermine the greenhouse extent in the first instance; global average temp is based on Teff figures; they are in turn based on the 'grey body' radiation emissions; that is the 279C amount; how can you, on the one hand say the global ave temp is 288 based on the 279C amount and then refer to the 255C amount to establish the extent of greenhouse? In saying this I am assuming both 255 and 279 have been albedo adjusted.
NT: ". Such a situation may occur, for example, when a surface emits infrared radiation and is simultaneously irradiated from a high temperature source such as the sun. The grey-body assumption also becomes tenuous when the range of active wavelengths contains strong emission (or absorption) bands.""
That situation is adequately dealt with by the various Line By Line integration programs that are about. One needs to remember that the total average radiation is a single number likewise the the average temperature is a single number and the grey body assumption is just a way of approximating the effect of having a non – isothermal body that has coloured radiation (and absorption and reflection). To deal with spatial and temporal variation you use equations like Arthur's (which I have said are fine) and to deal with colour (variations along the the spectrum) you do convolution integration of the Planck law with the empirical measured data from a database like HITRAN or GEISA as with Miskolczi's HARTCODE to obtain a grey body equivalent. This is not a grey body assumption like I have used above on what amounts to back of the envelope calculations.
I see Jan neatly excludes Gaia in our discussion of working bodies
gavin: "I see Jan neatly excludes Gaia in our discussion of working bodies"
I didn't even think of her hope she isn't offended.
Jan, you have used the grey-body assumption. That's why you are claiming emissivity=absorptivity.
"Real objects never behave as full-ideal black bodies, and instead the emitted radiation at a given frequency is a fraction of what the ideal emission would be. The emissivity of a material specifies how well a real body radiates energy as compared with a black body. This emissivity depends on factors such as temperature, emission angle, and wavelength. However, it is typical in engineering to assume that a surface's spectral emissivity and absorptivity do not depend on wavelength, so that the emissivity is a constant. This is known as the grey body assumption."
This is an assumption as I pointed out it is not universal and when you use it when the absorbed light and emitted light are of very different wavelengths you get serious errors.
This is why Arthur didn't us the same values of emissivity and absorptivity.
It has nothing to do with heterogeneity of the object, but rather that the object emits at very different wavelengths to which it absorbs.
Cohenite, the 288 is a calculation, it's not the 'measured' average temp.
the 288 comes from calculations based on the IR absorbing properties of greenhouse gases (and I think uses a value of 300 ppm CO2).
"Since the emissivity (weighted more in the longer wavelengths where the Earth radiates) is reduced more than than the absorptivity (weighted more in the shorter wavelengths of the Sun's radiation), the equilibrium temperature is higher than the simple black-body calculation estimates, not lower. As a result, the Earth's actual average surface temperature is about 288 K, rather than 279 K."
The 255 is the temp from measurement of outgoing radiation.
The 279 is a hypothetical temp that is not actually measured, but is the black body temp of an object the same distance as the Earth from the Sun.
NT; you've done some work and upset Jan; good effort! Now, I don't won't to leave this here because I think it's crucial to establish what the greenhouse effect is; but I'm busy today; so, when I get a chance I'm going to relook at the Essex, McKitrick Andressen paper; in the mean time here is a variation of the Motl piece for determing the difference between the average temp and the average SB;
http:halgeranon.blogspot.com/2008/02/much-ado-about-noting.html (// excluded)
Nb; after some convoluted analysis the author arrives at a differential between the 2 indices of ~ 10%! Motl's calculations suggest it could be larger, and even Arthur notes a 5% discrepancy, but his is a consistent gap, which is unrealistic; the point is if different Tave can produce differenct Teff, and vice-versa, how can anyone say with any confidence what the greenhouse is?
I'm exhausted…
I agree the ACTUAL exact number for the Greenhouse Effect would be impossible to determine. I think what you can get is a ballpark figure… So they noted the diff between the 255 observed and the 288 expected… Hmmm maybe I got that wrong.
Which is why GCMs don't solve all this with global averages. hmmmm
And it's why I recomend our focus be on the oceans not the atmosphere
Gavin, so do you think a sea surface temp is enough? Or is it some sort of energy content we need?
Luke, yeah the words 'Global average' get thrown around way too much – I don't know what relates to what anymore. GCMs are better as they at least try and broadly divide the world up into areas and look at each area.
Peter…I was not taking a shot at you and I did pick up the gist of your arguement. When I go off on a rant like that it is often as much for my benefit as anything. After having typed it all out, it seems a shame to delete it all, since some demented soul like me might find it interesting.
Don't take it personally…I did not intend it that way.
NT: "you have used the grey-body assumption. That's why you are claiming emissivity=absorptivity."
Yes I did as I said it's an approximation but the rule applies for line by line as well and you get an effective absorptivity and and effective emissivity which is spectrally sensitive (which is, if you understood it, is what your objection is) that you can then use the same way as you would the grey body emissivity and absorptivity. The same rule which applies is Kirchoff's law because the fluxes irrespective of wavelength i.e incoming visible & outgoing IR must sum to zero for a body in thermal equilibrium.
"The grey-body model becomes prone to significant error when the radiant energy spans a wide wavelength range that encompasses the visible as well as the infrared. Such a situation may occur, for example, when a surface emits infrared radiation and is simultaneously irradiated from a high temperature source such as the sun."
The Earth is exactly this.
If you assume, for approximation purposes that emissivity=absorptivity, in a situation where "a surface emits infrared radiation and is simultaneously irradiated from a high temperature source such as the sun." (ie the Earth), this approximation is "prone to significant error".
This would explain why all the other solutions that I found don't use emissivity=absorptivity.
"The same rule which applies is Kirchoff's law because the fluxes irrespective of wavelength i.e incoming visible & outgoing IR must sum to zero for a body in thermal equilibrium." If you look at the *fluxes* on the 'typical' greenhouse effect diagram you see that they do sum to zero.
NT (Oct 17, 8:56 am) – no, the 288 K, or 15 C average is the measured average surface temperature of the Earth, when averaged over the entire surface, over a year's worth of seasons. Instantaneously any point on the surface is typically within about 10% of that number (most of Earth's surface is liquid water that stays between 0 C and about 30C, so just a 5% range). Averaging the numbers from ocean and land measurements, appropriately weighted by the area per observation, gives you a real observational average number to within a fraction of a degree. The satellite observations (MSU, etc.) can also get near-surface averages quite easily, and there's no big discrepancy or uncertainty in that observational average.
Of course, typically the numbers bandied about in global warming discussions are not these absolute temperatures, but the temperature *anomalies* – this factors out seasonal variation (as much as 2 degrees C difference in the average from winter to summer) and also allows for more precise comparison since it cancels out some systematic biases. But the absolute average is a real number as well. Whether it is meaningful or not is another matter – but as my paper shows, it at least has the meaning that the absolute average (T_ave) has to be less than (or equal to) the effective radiating temperature of the surface, which certainly is a meaningful number.
Jan (Oct 17, 7:03 am) – your original criterion was a body where there is "equal incoming and outgoing heat". I assumed you by "heat" you meant "energy", however in this latest comment you state "I radiate more than I absorb". There is no reason to limit energy exchange to radiation, other than for a body like the entire planet that has no other mechanism for the exchange. Measured overall, your body takes in food calories and burns them, does useful work, and emits the resulting energy as heat. Overall there must be a balance. That is exactly the same balance that exists for Earth as a whole – incoming energy comes in in a high-quality form (short-wave solar), perhaps does useful work of various sorts (including supporting all the life on the planet), and is rejected as heat. It must balance, but it is most definitely not in equilibrium.
Yes, of course, a body in equilibrium is also in a steady state. But it is a trivial form of steady state, where nothing interesting can happen. Equilibrium implies steady state, but the reverse is emphatically not true.
The specific reason this is important is because equilibrium implies the principle of detailed balance, where every forward process is exactly matched by a reverse process, and it is this principle of detailed balance that enforces the form of Kirkhoff's law you have been talking about, where absorption equals emission. Absorption equals emission in equilibrium simple because one is the reverse process of the other, and in equilibrium every process is matched by its reverse.
But not so in a steady state. Total energy absorbed must equal total energy emitted, but the processes are not the reverse of one another. If they were, then all the outgoing radiation from the Earth would leave as short-wave radiation in a narrow band heading straight for the sun. Or conversely, matching the outgoing thermal radiation from the Earth, the planet would receive a nearly uniform spread of incoming radiation from all directions, at long wavelengths.
But neither of those conditions, which would be required if the planet were actually in thermal equilibrium, are what is observed – and nor are they the conditions I impose on the incoming and outgoing radiation in the model I used.
My model is steady state, not thermal equilibrium. Your conclusion about emissivity simply does not follow. I think I have repeated this and explained it enough by now.
Oh thanks Arthur,
So what is the modelled Average temp for, say 300ppm CO2? Are there any easy to follow programs?
cohenite: "that is the global average temp; I have already referred to the papers by Essex and, in particular Pielke, and the Motl piece;"
Lets look at the issues here first of all that averaging temperature to calculate radiation is trivially incorrect as G&T, McKitrick & Essex etc point out. It suggests for example that the temperature at Vostok influences the radiation from Jakarta which is at best not obvious and at worst (and most probably) utter nonsense. If however you are out to determine a statistical index of global temperature then the temperature at Vostok and Jakarta should have equal influence on the index and the simplest way to ensure this is so is to include them in an average.
However it does work out if you take average temperature temperature profile and us it to calculate average kinetic energy at each level of the profile sum it and sum the potential energy at each level for the same mass you will get a {PE}/{KE}= -2 if you haven't biased the average. WE can do this because A the Virial Theorem which states {PE}/{KE}= -2 is a statistical theorem and KE has a linear relationship with temperature. Using averages of temperature is not a universally incorrect thing to do as many who read those papers without generally understanding them are led to believe. Of course where using averages is valid the trick is not to introduce bias into them.
"the point is if different Tave can produce differenct Teff, and vice-versa, how can anyone say with any confidence what the greenhouse is?"
There is no reason for effective temperature which is always a black body equivalent to be equal to the equilibrium temperature though we can calculate the equilibrium temperature from it if we know the emissivity. We can know the emissivity if the object is in thermal equilibrium and we can measure the albedo because under the condition of thermal equilibrium emissivity = 1 – albedo following Kirchoff's law. The assumption is the the black body equilbrium temperature is the global average temperature the earth would be without polyatomic gases in the atmosphere. The measured average global temperature is the temperature it is because of the presence of those gases held to be 288K and the greenhouse effect is the difference.
The effective temperature is the equivalent black body temperature of a body radiating at a given rate. For earth this is a measured rate of ~235W/m^2 which works out at 254K. There is no reason to assume this figure is in any way related, as some have been suggesting Arthur included (I think??), to the equilibrium temperature the world would have without GHG present because it is measured with GHG which were certainly NOT sucked out of the atmosphere when the bird that was flying measured the outbound radiation.
Thus with a temperature of 288 which will radiate 390W/m^2 and an actual radiotion of 235 W/m^2 leaves us with an emissivity (YES NT IT IS SPECTRALLY SENSITIVE) which is measured as a bulk parameter as being 235/390 ~ .602 using K & T 1997 numbers.
So if albedo is .7 then the difference in emissivity and that number (.602) can probably be considered greenhouse effect.
I have my doubts though. A difference of .098 in emissivity is a far cry from a difference of .298 if as Arthur and others are suggesting the non GHE emissivity is 1. Therefore a more realistic number IMO.
Thanks to Arthur for stating in detailed fashion what is the greenhouse and AGW effect; some food for thought in respect of radiative and thermal flux and states; I disagree with his comments about the advantages of temperature anomalies for reasons covered in my specific posts. Jan's observations about the Virial Theorem and temperature is another reason for avoiding temp anomalies where bias is introduced via a base period and interpolation and scaling.
Jan, thanks too for your help; I still have a couple of issues; Arthur says;
"Absolute average (Tave) has the meaning that the Tave has to be less than (or equal to ) the effective radiating temperature (Teff) of the surface, which certainly is a meaningful number."
The TOA out radiation is 235W/m2; the Teff at the surface for that is 255K which is 279K reduced by an albedo of .3; however, because of GH the Tave is actually 288K.
If the enhanced GH and AGW are correct then the Tave of 288K will increase but the TOA outward radiation of 235W/m2 will not because at any unit of time the IR is being trapped and reradiated isotropically to Earth 50/50; certainly if the 235 does increase it will be less than the increase in the Tave of 288 if AGW and EGH are correct.
The issue is can the Tave of 288 remain stable while Teff (as indicated by the 235W/m2) fluctuates; Pielke's paper suggests it can; Motl has provided a working example where up to 9W/m2 variation in Teff can be accomodated by a stationary Tave; 9W/m2 is ~ 2.5C; the halgeranon link I gave provides a theoretical framework for divergence between Tave and Teff of up to 10%; Tave could increase or decrease by 28.8C and the Teff and the 235W/m2 would not change.
So, what the hell is the greenhouse amount?
Arthur" " assumed you by "heat" you meant "energy", however in this latest comment you state "I radiate more than I absorb". There is no reason to limit energy exchange to radiation, other than for a body like the entire planet that has no other mechanism for the exchange."
Why do you insist on irrelevancies to defend you indefensible position. You gave a silly and incorrect example of a steady state meeting those conditions without being in thermal equilibrium.
I don't know whether you are at room temperature or not though I suspect not (are you alive?). My body does not meet both those conditions it has an almost constant temperature but it almost never radiates the same amount it absorbs irrespective of the presence of other forms of heat exchange (I have designed quite a few heat exchangers) radiative equilibrium or balance (it's the same thing) is a necessary condition for thermal equilibrium, so I mentioned both. For a body such as earth orbiting as it is in a vacuum is a closed system where matter is not exchanged with space (at significant levels) but energy is.
WRT: "I assumed you by "heat" you meant "energy"" Thermal energy in motion or being transfered is heat. I just think it's more appropriate in the context you think it's overly pedantic?
"Equilibrium implies steady state, but the reverse is emphatically not true."
How many times do I need to make that point also or point out that i day days ago before you realise it?
"The specific reason this is important is because equilibrium implies the principle of detailed balance, where every forward process is exactly matched by a reverse process, and it is this principle of detailed balance that enforces the form of Kirkhoff's law you have been talking about, where absorption equals emission. "
That is precisely the underlying assumption of your model or else your model would be having an continually increasing or decreasing temperature which you specifically say it does not.
For planet earth to have a constant temperature with heat being poured into it by radiation from the sun it must be pouring a equal amount of heat into space one precisely the reverse of the other. It is quite irrelevant that the incoming heat and outgoing heat have different wavelengths as long as heat loss = heat gain and Kirchoff's law holds valid.
now you are still saying your model is not a thermal equilibrium model please try to explain once again and try not to use examples that have an internal energy source and regulating system. Such systems are most unlikely to be in thermal equilibrium with their environment as the earth is with the sun and space.
This is interesting. It sounds unlikely to me that changing Teff can still result in Tave remaining the same.
Do you still have those links?
I wonder if the TOA flux is expected to decrease due to AGW. That would certainly be measurable, no?
Based on this thread I think Jan should condense and rewrite his argument with all the math outlined for another thread if not his own paper
Definitely this all needs to be distilled – there are a lot of dead ends.
You would think so.
"Why do you insist on irrelevancies to defend you indefensible position. You gave a silly and incorrect example of a steady state meeting those conditions without being in thermal equilibrium. "
I think he keeps trying to dumb it down since you don't seem to understand what he is saying. As I said earlier, you have to be able to talk the talk, or it's all just a waste of time. As soon as he explains something to you, it's as if he hadn't spoken. He tries again, you just accuse him of being irrelevant, since he keeps on trying to get his point across to you.
NT; for GH and EGH the TOA flux would not have to change; it's a bit like RH in reverse; CO2 can be increasing the atmospheric temp, increasing its saturation point but if SH is not increasing or not increasing at the rate of air temp increase the RH will be declining meaning the energy increase in the air due to GHG's is being counterbalanced by decreasing RH; so, with Teff remaining stable while Tave increases you would say the GH effect is increasing (assuming stable insolation and no ocean heat storage); the links;
The Pielke paper link is not working but the reference is Journal of Geophysical Research, VOL 112, D24S08, 2007; Pielke Sr et al
The motl link which refers to the Pielke paper is;
The Algernon link, which is based on Pielke;
http:halgeranon.blogspot.com/2008/02/much-ado-about-nothing.html (// excluded)
Thanks Cohenite, yeah I get you re: TOA flux.
I had a (quick) read and I think I have a possible solution.
Sorry got called away.
Ok, so It looks like Motl is using Tave to demonstrate there is no unique Tave for any Teff, and that the same Tave gives different Teffs.
Not sure why he is doing that – no one calculates Teff using Tave. And it's not surprising now that I thought about it. Teff says nothing about the distribution of heat in the system (hope I am using the right terms here) – it is another average. So of course there are multiple Taves for any Teff (we call that weather). Now I know you'll say but he uses different distributions of heat ( 4 different regions) that each give the same Tave but different Teff.
If you look at the bottom of the Algernon page you can see that Ray Pierrehumbert gives his thoughts.
As to there not being any global average, I will continue thinking. I have a feeling it has something to do with the fact that a Global Average Temp says nothing about the heat distribution, it is merely a comparison figure. Global Average Temp will never make any 'predictions' or define any conditions. I don't believe anyone uses them in that way, they just become a quick and dirty comparison.
Hmmmm Need to think/read more
In other words, Pielke has no idea what he is talking about.
He claims
""In constructing a global average of T', its spatial distribution matters since T' in regions with a baseline colder temperature have a significantly smaller effect on the return of heat energy to space (through infrared emission) than regions with a warmer baseline temperature."
Thus, by constructing a global average value of T' in the equation for dH/dt introduces a significant error in diagnosing the actual global radiative imbalance. A 1C increase in surface temperature in the higher latitudes has less of an effect on the outgoing long wave radiation than a 1C increase in the tropics. This also means that using the mean daily temperature over land, rather than a diurnal cycle where the long wave emission from the surface is substantially larger at the time of maximum daily temperature, introduces yet another error.
Thus when the science assessments and policymakers claim we need to keep the global average temperature change below some threshold (e.g. 2K), they should be questioned on how this number is constructed both in the observations and in the models."
But PH says
"A lot of you guys are getting somewhat led up a garden path. There's no business about "scientists missing an error of 17%" going on no matter how you do the arithmetic. Climate models DO NOT CALCULATE THE ENERGY BUDGET USING A SINGLE GLOBAL MEAN TEMPERATURE,… Climate models do a radiative transfer calculation several times a day at each gridpoint, incorporating the full variation of temperature.
The sort of thing you guys are talking about only tell you how big the errors are in the most primitive blackboard-type zero-dimensional climate calculation, where indeed you do do the energy budget in terms of a global average temperature. The fact that the errors made by doing so are so small is in fact why you can get pretty far with such simple calculations, especially on a planet like Earth or Venus with a thick atmosphere and or ocean to redistribute heat and make temperature more uniform."
Jan Pompe (October 17, 2008, 4:21 pm)
Other people seem to be able to understand what I'm trying to get across, why not you?
One last try though. If Earth in my model was in a thermal equilibrium state, its temperature would either by 5000 K (the temperature of the Sun), or absolute zero (since I included no incoming radiation from the depths of space). That is because, the Earth in my model is exchanging energy with two other bodies: the Sun, and the rest of the universe. A body can be in thermal equilibrium only if all of its exchanges of energy are with other bodies that are at the same temperature (and then each such exchange is, in detail, balanced – it receives back from each such body exactly the same amount it sends).
The Kirkhoff's law principle that you are asserting is that, in thermal equilibrium, there is detailed balance between absorption and emission such that every radiation exchange with other bodies is balanced: the amount of energy exchanged is identical, and the absorptivity (1 – reflectivity) and emissivity are the same. This works in equilibrium because the bodies you are exchanging with are at the same temperature, so their range of radiating wavelengths is the same as yours. So when you receive energy from them by radiation at a given wavelength, you can absorb it with whatever the absorptivity is for that wavelength, and then the Planck's law distribution being exactly the same (since you are at the same temperature as the sending body), you will emit that same quantity of radiation back. That's where absorptivity and emissivity must be equal.
In contrast, for the real Earth, the exchanges of radiation are *not* with bodies that are at the same temperature, and therefore the radiation wavelengths are very different for absorption (at short wavelengths corresponding to the high temperature of the Sun) and emission (at long wavelengths corresponding to the much lower temperature on Earth). The absorptivity and emissivity numbers are different because of those differing wavelengths for absorption and emission. As has been repeatedly stated here, with many citations to the literature and observations.
The total energy absorbed must be the same as that radiated, just as the total energy intake of your body (including all the calories you eat) must be balanced with the total energy output of your body. That's steady state. But there is no detailed balance for a living body, just as there is no detailed balance for Earth, because the incoming and outgoing energy processes are very different, and do not correspond to interactions with bodies at the same temperature as the planet.
NT – you ask "So what is the modelled Average temp for, say 300ppm CO2? Are there any easy to follow programs?"
Unfortunately, no, but the IPCC reports give some overview of the logic and reasoning – in particular chapter 2 on "radiative forcing" and chapter 8 on climate models, of the recent (AR4-WG1) report on the science. The first problem, the "radiative forcing" issue, is that CO2 (and other GHG) absorption consists of a very large number of distinct lines, each of which is dependent on local temperature and pressure, so you have a complex summation problem from the start to see how radiation changes through the atmosphere when you change GHG levels. Computer codes like the Modtran program can do this in some detail, and the GCM's use something of that sort as well. There are also fitted formulas that seem to capture the behavior reasonably accurately, one of which is the logarithmic function most often quoted, which gives the change in radiation as proportional to the log of CO2 levels in the atmosphere. Doubling CO2 in that formula gives an increase in "radiative forcing" at the tropopause of about 4 W/m^2. What is actually happening is that by increasing CO2 you are increasing the atmosphere's absorption of radiation everywhere, and causing a contraction of the region around the tropopause that does most of the radiation into space, and therefore (since the closer you get to the tropopause the colder it gets, actually below the 255K T_eff), decreasing the rate at which Earth releases energy to space. There are related effects of cooling the stratosphere and raising the altitude of the tropopause. So this is the immediate effect of adding GHG's: making the Earth look like it's gotten colder, from space, so that it radiates less energy, and retains some portion of what it gets from the sun. An imbalance.
The question then is what is the impact of that imbalance, of 4 W/m^2 for doubling, say, on the temperatures at the surface. There is no immediate impact, of course, because it takes a while for that additional retained heat to accumulate. But gradually it does accumulate, and temperatures from the surface to the tropopause should increase (and below the surface into the ocean and underground, as well). There are other responses: higher surface temperature means more water vapor (specific humidity will increase), and that further increases the atmosphere's absorption of thermal radiation, at least in the regions where water vapor levels change. Snow and ice melts. Clouds respond in some fashion to the changing temperature and humidity profile in the atmosphere. Increased water in the air changes the "lapse rate", the rate at which temperatures decrease with altitude.
Eventually, all these responses to the added heat, acting together on their various different time scales will act finally to increase the temperature at the tropopause, increase Earth's outgoing radiation levels, and bring things back into a steady-state balance. The resulting surface temperature is the central output of the complex climate models we have – and the IPCC estimate of between 2 and 4.5 K increase in temperature for a doubling of CO2 is probably the best estimate we have now for the ultimate response. IPCC also estimates a "transient" response (the short-term temperature increase while CO2 is still in the process of increasing) at about 1.5 to 3 K per doubling, but of course that depends on the rate of CO2 increase relative to the ability of things to respond.
Aside from the models, there is much other evidence that goes into the IPCC estimate – all of it in essentially good agreement on that range of responses. IPCC AR4 WG1 is well worth reading in detail, not just the summaries but the actual chapters of science. It's long though!
Cohenite: " Arthur says;
He agrees with T&G on that. It's a function of how Teff is calculated from temperature readings by calculating the 4th power and averaging that then taking the 4th root. It is a valid way of doing it and avoids the problem Lubos is talking about. There remains the problem of how accurate it is and whether or not there is a bias and I'm sure those who calculate are aware of the problems there and are careful (I would hope).
Whoever calculating the Teff from averaged radiometric readings from space is equally valid and one that I prefer because the coverage is less likely to introduce a bias. however one must account for emissivity reducing the radiated output. Taking a long term average reduces the degrees of freedom to the extent that it is effectively a constant temperature (as G&T you can't derive a differential equation for an averaged function p88) and the radiative balance must also hold (on average) and consequentially Kirchoff's law also. Therefore one can use the albedo (measurable by the very same satellite with a different instrument) to calculate the effective average temperature of the surface + atmosphere. It will take into account the heating of the stratosphere and clouds due to SW radiation being absorbed etc. everything. We do that and the effective average temperature is 278 and it is interesting that this does not change with albedo changes as long as the emissivity changes with it though the 235 W/m^2 will rise and fall with it and consequently the effective black body temperature will too.
The surface temperature and the lapse rate will change moving the altitude that will have this characteristic temperature keeping {PE}/{KE}=-2 as per the virial theorem.
The upshot is that the greenhouse effect which is the difference between heat radiated from the ground and heat radiated to space (according to Imandar and Ramanathan 1997) really has no bearing at all on the average Teff the only thing that can change the equilibrium temperature is orbit, the radius of the sun or the emissivity of the sun.
Comparing the surface temperature to the equilibrium temperature is then irrelevant to the greenhouse effect. That must be calculated from the measured surface radiation and the measured OLR (total to space) albedo and emissivity which are strongly coupled can affect this.
K & T 1997 numbers give a greenhouse effect then of (390-235)/ 390 = .4 & Miskolczi 07 from S_u=3OLR/2 has it at .333 (empirical = .332). The differences? K&T use the USST76 profile which I test against the virial theorem and it failed Miskolczi used TIGR profile which I also tested it passed much to Ferenc's surprise it seems.
What remains a mystery is how much CO2 can cause the greenhouse factor to change.
Arthur: "Other people seem to be able to understand what I'm trying to get across, why not you?"
Other people are more easily fooled.
For a start
"If Earth in my model was in a thermal equilibrium state, its temperature would either by 5000 K (the temperature of the Sun), or absolute zero (since I included no incoming radiation from the depths of space). "
Having picked myself up from the floor yet again you really must stop this my ribs can't take much more.
This is absolute rot. You cannot achieve a 5000 K temperature without some serious concentration of the radiation. A You achieve thermal equilibrium when the incoming heat energy is equal to the outgoing i.e balanced i.e. in equilibrium
"That is because, the Earth in my model is exchanging energy with two other bodies: the Sun, and the rest of the universe."
The two bodies are irrelevant it's total energy coming in to total energy leaving if that is balanced it's in equilibrium and for earth the only way it can enter and leave is via radiation. ego it's in radiative balance meaning equilibrium and Kirchoff's law applies.
"In contrast, for the real Earth, the exchanges of radiation are *not* with bodies that are at the same temperature,"
Again it's irrelevant it's energy in versus energy out that must be balanced i.e in equilibrium. What temperature it can get up to is easily calculated:
Yields an equilibrium temperature of 278.7K now taking K&T 97 who have an absorbed radiation and emitted radiation of 235W/m^2 with an albedo of .31 and so setting emissivity to .69 we get an equilibrium temperature of 278.38 K geez that's close and what a surprise it must be for you.
"The total energy absorbed must be the same as that radiated,"
Well it is isn't it?
"just as the total energy intake of your body (including all the calories you eat) must be balanced with the total energy output of your body"
Yes that's true but since that food becomes an internal energy source you know reducing ATP -> ADP ->AMP in the process of building proteins burning glucose etc but I'm not in any way in thermal equilibrium with my environment and wont be until I go to room temperature which is currently at ~19C my skin temperature is about 31C.
Arthur I showed you paper to a friend of mine he's an engineer he had a little chuckle he teaches so he knows people fairly well he mad the comment that you would probably waste an extraordinary amount of energy defending that boo boo. It seems he's right.
Don't you realise that with your integrals or even just dividing the solar constant by 4 you are setting up in your model a virtual black shell around your model earth that is maintained at 278.7 K?
1366/4 = 341.5 now to get the effective temperature
(341/5.67E-8)^25 = 278.4K again it must come as a surprise. What is more it's only the distance from the sun the radius of the sun and the temperature (or emissivity of the sun) that can affect that albedo and emissivity wont change that so the equilibrium temperature is not affected by anything that happens or can happen on earth and it's only relevance is that it decides the OLR. The interesting thing is that if you calculate the black body equivalent you will get the same result as setting the emissivity to 1.
So what is the fuss about? It highlights the problem with wrong method + right result = bad science.
What it means is that it does not describe what the surface temperature will be without GHG but what the bb temperature looks like from space. Check the numbers of Venus to see what I mean from space it looks ~22K cooler than earth does at 232K. Her equilibrium temperature is 232 * sqrt(2) ~328K at the other end of that virtual seesaw 737K.
I haven't looked closely at Inamdar & Ramanathan 97 yet but they appear to have take the greenhouse factor as
(Surface radiation – longwave radiation)/(surface radiation)
Maybe the know something.
Jan; thanks mate; very impressive; I would really like for you to do a little post on your point about the difference between K&T and Miskolczi in terms of the greenhouse effect, with a user friendly explanation so I can put it on a range of T-shirts that I wear to Government climate change meetings. A couple of points; I too, from my much inferior knowledge, was disappointed with Arthur's latest responses; his comment about thermal equilibruim alternatives being either 5000K or 0K is bunk; if Alan Siddons has read it he will still be running around screaming and tearing his hair out. I must also say that Arthur's observations about Kirchhoff are unexpected; he says;
"This works in equilibrium because the bodies you are exchanging with are at the same temperature."
3points; he seems to ignore enthalpy and latent heat; his comment about SH seems to confirm that; 2ndly why isn't Stewart's Law, as per the Robitaille piece, invoked; and the concept of the Local Thermodynamic Equilibruim (LTE) seems to contradict Arthur's point. 3rdly, Arthur's comments about lags are not confirmed by reality; that is, heat isn't being stored in the oceans; there is no lag between SST and land and atmosphere temps; Trenberth shows temp lags in the system average a few months, which is much shorter than Schwartz's corrected figures of 8.5 (+-2.5) years; Bob Tisdale has done some great graphs showing that ENSO doesn't accumulate but the statistical temp effect of the PDO phase changes do; if lags are occuring where is the heat?
A reply to Will who thinks that Pielke doesn't know what he is talking about and RPH does; Will quotes Ray having a spray about the absurdity of scientists missing an error of 17% of the energy budget; seems easy enough to do; but I especially like Ray's comment about our Earth "with a thick atmosphere and or ocean to redistribute heat and make temperature more uniform."
A bit of research; the lowest recorded temperature was at Vostok station on 21/7/83 at -89.6C; the highest temp was at Al,Azizyah on 13/9/22 at +58C; that's a difference of 147.6C or ~26W/m2; getting close to Ray's 17% there, and also a very strong argument that the Earth is cooling; the world's greatest temp range at one place was at Verkhoyansk, Siberia where it went froma chilly -68C to a balmy +37C over a matter of 6 months; that's a 105C, or nearly 19W/m2 turnaround; even old Aussie can produce a differential of 57.2C at White Cliffs and that happened in less than a month. Losing 17% never seemed so easy.
Cohenite and Jan. The problem you have is that every other reference to this theory basically repeats what Arthur has said. If you think you are right, then fine, but note that I can find no reference to support your findings. So this is either a critically important finding on your part or you are just wrong. In this case, there is no point in anyone attemptingto debate this anymore, you need to summarize your findings and submit them to scrutiny. Outside this blog preferably as you'll only get cheerleaders here. Maybe Jan you could speak to your old engineering lecturers? Or even lecturers in engineering or physics at a nearby uni?
I am sad that you don't seem to understand what Arthur is saying, as I thought we were very close to agreement. I have seen enough know for my own satisfaction and don't need to discuss this any further. All I can suggest is you check your assumptions.
For example your absorptivity=emissivity assumption
Cohenite, check the commutivity of what Motl does. Can the Stefan-Botzmann equation be used as he does it (do you do each as a separate SB equation then average or do you have to average the temps before you do the SB). I get the feeling that dong four SBs then averaging them is inappropriate.
Fair enough Nathan; one thing about the Motl piece is that there is an artifice in there; the issue is what. Jan did mention a solution above, about which he is agreement with Arthur, or rather Arthur is in agreement with G&T; I think Jan's 12.33am comment immediately above is very strong; the point you are avoiding is that neither Jan nor I, nor G&T, are saying that CO2 doesn't have an effect; we are disagreeing with the AGW extent of that effect, and the fallacious greenhouse analogy; it seems that AGW spokespeople are forcing the science to conform to what the theory wants; personally I don't care; I'm too old and too rich; but I dislike cant and I respect science and I would hate for science to be subverted for political and ideological reasons again (think Lysenko); anyway Jan's 5th paragraph actually agrees with Arthur's semi-opaque vertically expanding atmosphere (ie increasing the altitude of the tropopause); but Jan notes it has a different meaning to what AGW allocates to it; one that is consistent with Miskolczi.
Cohenite, it hasn't been "subverted for political and ideological reasons" all of this was developed well before it became in any way a political problem.
Motl is a non-issue, all he is saying is that
(1^4 +2^4 +3^4 + 4^4)/4 gives a different answer to (1 + 2 + 3 + 4)^4/4. It's not that amazing.
(341/5.67E-8)^25 = 278.4K again it must come as a surprise. What is more it's only the distance from the sun the radius of the sun and the temperature (or emissivity of the sun) that can affect that albedo and emissivity wont change that so the equilibrium temperature is not affected by anything that happens or can happen on earth and it's only relevance is that it decides the OLR. The interesting thing is that if you calculate the black body equivalent you will get the same result as setting the emissivity to 1. "
This is exactly what is on the Wiki page about Stefan-Boltzmann. They then go on to describe why that is not appropriate.
Sorry I shouldn't have replied… I should let it go… So I will… I need to be doing my Stiff diagrams…
Malcolm Hill says
Let me guess–the summary of 414 posts on Arthurs paper IS…..
We do not know with enough certainty to bother about it
Relative to all the other troubles in the world, it is a nonsense, and until the IPCC and peer review as a process is reformed not another dollar should be spent on it.
NT "but note that I can find no reference to support your findings."
Please turn on your critical thinking for a moment.
Kirchoff's law.
"At thermal equilibrium, the emissivity of a body (or surface) equals its absorptivity."
and "his theorem is sometimes informally stated as a poor reflector is a good emitter, and a good reflector is a poor emitter."
It's actually just common sense and common experience.
Arthur insists that a poor absorber is not just good emitter but a perfect one – it's contrary to common sense and common experience.
Hold this thought while we look at another
"http://en.wikipedia.org/wiki/Black_body#Assumptions"
"If we assume the following:
1 The Sun and the Earth both radiate as spherical black bodies.
2 The Earth is in thermal equilibrium."
They arrive at
Te = Ts. (1-A)^(1/4).sqrt(rs/2R) they have left out emissivity (E) as required by kirchoff's law it should read
Te = Ts.((1-A)/E)^(1/4).sqrt(rs/2R)
leaving E out from that position in the equation is equivalent to setting it to 1.
they explicitly make the assumption in 2 that the earth is in thermal equilibrium (do you think they mean something else?) and Kirchoff's law states for a body in thermal equilibrium E = absorptivity = 1-A then (1-A)/E = 1. you are then left with the same equation I wrote out (note I'm not claiming i derived it because that would be plagiarism) here.
When they made the assumptions to be consistent they would have to leave out two or specifically state in 1 also that earth absorbs as a blackbody and in the equation setting A to 0 (or absorptivity to 1).
You have to get used to the idea that mistakes do get made in text books and there are a lot of sheep about and wikipedia is quite unreliable as this example shows you have self contradictory articles.
NT "I am sad that you don't seem to understand what Arthur is saying, as I thought we were very close to agreement."
I understand perfectly what he is saying he is most unconvincing to someone who has worked extensively with heat (not just taught it or read a bit about it) and still do on occasion. He really needs to get to work on some systems theory. The remark my friend made about his going to extraordinary lengths to defend his boo boo is bearing out this is the second round I have had on it with him. I haven't changed my view the last time he also pointed out an error I made in the math instead of arguing I thanked him and haven't made thte same mistake since. He on the other hand didn't try that nonsense that the equilibrium temperature should be 5000K like this time. I wonder he will use to try to defend the indefensible. Perhaps he'll read up on systems theory and find something in there he thinks he can use.
I wait with baited breath.
How many times do you have to be told. THIS IS NOT THERMAL EQUILIBRIUM!
Thermal Equilibrium is a very specific definition, the earth is not in a state of Thermal Equilibrium. If you can't get even the most most basic, and necesary, assumptions right, everything else you make from that assumption just has to be wrong.
Jan, I showed you this doesn't apply
It is just not true, it's a grey body assumption that doesn't hold when the incoming and outgoing radiation is of very different wavelengths.
You need to check the assumption that Kirchoffs Law is Universal.
That seems to be the bone of contention, and it is the only difference in our argument. If Kirchoffs Law is not universal and only applies in certain cases, then your argument falls apart. The links I gave you indicate that it is not Universal.
I will leave it to you to do your own research on this.
From Arthur.
"Jan Pompe (Oct 14, 12:36) – incoming solar radiation is not in thermal equilibrium with Earth, it is at an effective temperature of some 5000 K (the temperature of the sun's surface)."
Anyway, does Arthur win the Bet?
Ok, Jan.
I have discovered you are arguing exactly the same points on a different blog site, with the physicists in question. So I will retire.
SJT Look here and watch the barney unfold: http:landshape.org/enm/greenhouse-heat-engine/
Interesting isn't it that we reached the same point. On the question of whether or not Emis=Absorp… Hmmm. Anyway best of luck.
SJT, apparently not (look right up at the top). He didn't address all the criteria.
Nathan" " I showed you this doesn't apply"
How can you show what you only half understand?
SJT: "If you can't get even the most most basic, and necesary, assumptions right, everything else you make from that assumption just has to be wrong."
I am not the one making that assumption that is the problem Arthur claims that he isn't. heat energy in and heat energy out is balanced or in HIS OWN WORDS
If it didn't average to zero for a long period of time, the energy of the planet would cumulatively build or decline.
That's equilibrium no matter how you want to cut it. It's a trivial fact that the earth is not in equilibrium ever but that is not the assumption he made the buffer of it all it is a necessary assumption if your model is based on a long term time series average because that ends up being a CONSTANT. If you think you are so clever the why don't you give us a differential equation for an averaged function?
Jan, it's funny that you are claiming we are stupid when you are having the exact same debate with others…
"If it didn't average to zero for a long period of time, the energy of the planet would cumulatively build or decline. "
Interestingly enough, if you look at the geological timescale there is a case for there being a cumulative decline.
Jan, it's weird. You accuse people here of being ignorant or stupid, yet your whole argument is based around the work of Miskolczi, which was published in 2008… What did you believe before Misko came along?
"What did you believe before Misko came along?" He was like the rest of us, wondering in the wilderness; btw, I've tossed your Santer paper about there being a THS to the lads at Niche; I sure do enjoy Franko; he is one of the few who can put BPL in his place.
I wonder if Jennifer will consider having a post from either G&T and/or Miskolczi?
"he is one of the few who can put BPL in his place."
It's very hard to look objectively at a debate with this sort of partisanship…
Did you understand my commutivity comment? And why Motl's SB equations aren't any good?
Here's some interesting definitions I fould
"Thermal equilibrium is achieved when two systems in thermal contact with each other cease to exchange energy by heat. If two systems are in thermal equilibrium their temperatures are the same."
So according to this Arthur was right.
Jan?
But you aren't using the correct definition for what the state is, it's not "Thermal Equilibrium". "Thermal Equilibrium" has a very specific meaning, and implications.
Arthur wrote
What he have is a "steady state" situation.
It's a steady state, where the state's of the componenets aren't changing over time, not equilibrium, where they are identical.
That's where the idea of a 'forcing' comes into the picture. If the earth is in a steady state, a forcing will causing it to leave that state and enter another. In this case, by reducing the emissivity of the earth, it warms, since it will absorb more radiation, until it reaches a new steady state.
http://en.wikipedia.org/wiki/Climate_model
This yields an average earth temperature of 288 K [3]. This is because the above equation represents the effective radiative temperature of the Earth (including the clouds and atmosphere). The use of effective emissivity accounts for the greenhouse effect.
If Kirchoffs law applied to the earth, that is the total incoming radiation always equalled the total outbound radiation, it could never warm.
Kirchoff's law would only apply to a steady state situation. (IMVHO).
SJT: "If Kirchoffs law applied to the earth, that is the total incoming radiation always equalled the total outbound radiation, it could never warm."
you speak rubbish. Kirchoff's law applies to any body hat is in thermal equilibrium including simplified models of earth. If the models aren't constructed according to the physical principals they represent you get rubbish out of it regardless of the quality of the data put into it.
cohenite "I wonder if Jennifer will consider having a post from either G&T and/or Miskolczi"?
I'm not up on the latter but I'd like to get into a discussion about G&T's paper. There's some pretty deep stuff in there that invites dissection, and it might teach us all something about basis physics.
In particular, I'm interested in what they say about the surface warming the atmosphere. They claim the AGW crowd has it wrong, that references to 'net energy' increases are ambiguous and do not apply to a summation of heat quantities.
I think G&T are onto something. They also claim it is nonsense that a trace gas with a density of 0.03 % can have a 10 to 25% effect on warming. They do a quick calculation based on a box in space containing CO2 and dismiss it as a black body source. They claim the calculations for that situation are far more complex than what the AGW crowd have allowed for.
It's the wrong term.
Did you find out if Kirchoff's Law is Universal?
Nathan: "Did you find out if Kirchoff's Law is Universal?"
it is. Now it is possible for there to be radiative spectral differences in fluorescent bodies i.e. they emit at a different wavelength than at what they absorb (sound familiar) so you can get can get at a particular wavelength higher emission than absorbed. However conservation of energy which is the basis of Kirchoff's law will always win out. If you integrate the intensity over the absorbed and the emitted spectra the intensity or power will be equal.
This is what you see in Miskolczi's Fig 2 he took the profiles ad 226 locations and calculated the absorbed radiation versus emitted (the air did definitely not radiate as a black body) you'll not the small readings from Mars sow the same thing and you should also not that assuming a black body earth overstates absorption and using actual emissivity of .96 shows equilibrium.
Remember this is empirical stuff not theoretical.
NT; you're no fun when you get precious; BPL is always patronising; my maths is well behind me; I make my living verbally assaulting people not assaulting them by stats or maths; the point about commutivity and Motl (and Pielke and Algernon)is, as I understand it, that Tave and Teff are not commutative; Jan at 12.33am, 3rd para, says this can be overcome by calculating the 4th power and averaging and then taking the 4th root; I'm still getting my head around that; there comes a time when the stats and reality depart company; on the other hand there is also a time when the stats and reality are underestimated; your comment at 11.11am that (1^4+2^4+3^4+4^4)/4 is not commutative with (1+2+3+4)^4/4 IS amazing when the difference is translated into energy equivalents. Let's look at Motl's examples; 1st 4 are 313K, 293K, 283K, 263K; 2nd 4 are 310K, 292K, 284K, 266K; both sets ave 288K but the Teff varies from 399.26W/m2 for the 1st to 397.14W/m2 for the 2nd, a difference of 2.12W/m2 or nearly 1C. A great deal of the discussion has been about thermal equilibrium; as I understand it between the Earth and its externalities; this, imo, misses the point of the regional effect that Motl is describing, which is the effect at particular defined climate regions internal to the Earth; to illustrate this and the thermal equivalence between the regions within the Earth we should take the 4th root, x^1/4, of each of Motl's amounts; the reason for doing this I will explain below; thus
313 @ x^1/4 = 4.2
293 " =4.14
263 " =4.03 total = 16.47 av = 4.1175
2nd series;
310 "=4.196
292 "=4.13
266 "=4.04 total = 16.506 ave =4.1265
If we subtract the series the difference is 9^-03; a miniscule difference. The reason I have reduced the amounts by x^1/4 is too standardise, as far as possible, SB, by reducing the energy areas being compared; in this way they will conform to what eli has defined as Local Thermodynamic Equilibruims (LTE); see;
http:rabett.blogspot.com/2007/03/what-is-local-thermodynamic-equilibrium.html (// excluded)
Within any LTE Kirchhoff will apply; the issue is, will Kirchhoff apply between any 2 or more LTE's?
"you speak rubbish. Kirchoff's law applies to any body hat is in thermal equilibrium including simplified models of earth. "
The earth is not in "Themal Equilibrium", not even in a simplified sense. Steady State, yes, "Thermal Equilibrium", nothing like it.
Cohenite, Me Precious? No…
I think you may be missng the point with commutivity. If they are non-commutative, then what he has done is not correct. You cannot change the order of terms if you are using non-commutative terms.
((313+293+283+263)/4)^4 does not equal
((313)^4) + (293)^4) + (283)^4) + (263)^4) /4
The T term is the temp of the body, not the temp of a bit of the body.
This is the definition of the terms for the Stefan Boltzmann equation
"The Stefan–Boltzmann law, also known as Stefan's law, states that the total energy radiated per unit surface area of a black body in unit time (known variously as the black-body irradiance, energy flux density, radiant flux, or the emissive power), j*, is directly proportional to the fourth power of the black body's thermodynamic temperature T (also called absolute temperature)"
So what Motl has done is looked at four discrete blackbodies each with their own temp and calculated an average temp for all four… This is not the same as looking at one body with variations in it's temp.
I think the problem is that the Earth can be in Thermal Equilibrium with itself, that is the Energy the Earth receives should be very close to what it emits, but it is certainly not in Thermal Equilibrium with the sun.
So Arthur was correct in saying that the Earth is not in Thermal Equilibrium with the sun as it is not at 5000k. But it can be in Thermal equilibrium with itself in that Energy in = Energy out. So from this we see that Energy in = 235 W/m^2 and Energy out = 235 W/m^2
Note that Energy in = 0.7 of what we get from the sun, but Energy out is 100% of what we absorb.
cohenite: "Within any LTE Kirchhoff will apply; the issue is, will Kirchhoff apply between any 2 or more LTE's?"
Depends on how you define the "L" in LTE. If you get a small parcel it will be in LTE with a slightly larger parcel surounding it. The tautology should be obvious but if you have a parcel of a given size in LTE and divide that in half the two halves will be in equilibrium with each other (but not defined as LTE). I'll leave you to ponder that but it makes use of the principles of differential calculus LTE is only an approximation.
Nathan "I think the problem is that the Earth can be in Thermal Equilibrium with itself, that is the Energy the Earth receives should be very close to what it emits, but it is certainly not in Thermal Equilibrium with the sun."
You are getting warm but not hot yet. The earth that is assumed to be in radiative balance is not in equilibrium with the sun alone but with space as well so it's equilibrium temperature will hang somewhere between. Now there are two equilibrium temperatures to consider on that can only radiate back in the direction of the sun the back insulated (important consideration for solar heaters). You would expect to see that as the peak temperature on the face of the moon facing the sun (It has been warming ~7 our days). A back of the envelope will give this as the effective BB temperature of a 1366 radiator vi SB you will 394K NASA gives the peak lunar temperature as 394K.
The other is one where the the object as spherical can radiate in all directions to lose the heat and that (again the back of the envelope) is 1366/4 then applying SB for a black body and it will be ~279 so that then is both the steady state and equilibrium temperature we can expect on earth.
SJT You are still talking rubbish
So why did you mock Arthur when he said the Earth was not in Thermal Equilibrium with the Sun? And when he said it would be 5000k if it was. He was right.
Ok, so shouldn't the Energy in= Energy Out?
Energy in = 0.7 x 1366/4 = Energy out.
So the emittance = absorbance, right? So that the net Flux out doesn't need to be multiplied by 0.7.
I have already stated my opinion that Arthur's model is overly simplified. I don't think it adequately addresses the arguements posed by G&T. I am not claiming that a phenomena described by the greenhouse effect does not exist, I am merely questioning the basis of it. I think part of it may be right and part may be wrong.
In this Dec 2007 paper:
http://cfa-www.harvard.edu/~wsoon/ArmstrongGreenSoon08-Anatomy-d/Lindzen07-EnE-warm-lindz07.pdf
Lindzen addresses the issues at a much deeper level. He claims the current greenhouse model is overly simplified and makes some profound statements along the way.
For example, with reference to atmospheric temperature measurements by satellites and sondes, he says, "Contrary to the iconic statement of the latest IPCC Summary for Policymakers, this is only on the order of a third of the observed trend at the surface, and suggests a warming of about 0.4 degrees over a century. It should be added that this is a bound more than an estimate".
With regard to the effect of the oceans on warming, he says, "Irregular exchanges of heat between the deep abyssal waters and the near surface thermocline regions imply that the oceans serve as large sources and sinks of heat for the atmosphere, and these exchanges take place over time scales from months to centuries or longer. A very recent paper (Tsonis et al, 2007) suggests, in fact, that the surface temperature record can be accounted for by essentially superpositions of known oceanic fluctuations such as the Pacific Decadal Oscillations and the Atlantic Multidecadal Oscillations. There is, in fact, no reason to suppose current models are treating such matters adequately. Indeed, a recent paper from the Hadley Centre acknowledges this (Smith et al, 2007)".
Lindzen explains the widening of the tropopause and the opacity of the tropics to radiation, requiring thermal flows from the tropics poleward for emission.
You just can't describe the complexity of the system by claiming there's a layer of GHGs surrounding the planet which traps heat. Heat emission from the surface depends on much more than GHGs.
From what I could get from Arthur's posts, (I hope he comes back!), even the earth is not in a state of "Thermal Equilibrium", because radiation in does not equal radation out, in the sense that we have short wave radiation coming in and long wave going out. It will have a balance, at which point the local average temperature will stay constant. Change the amount of radiation coming in and out, and the balance will evenatually be restored, but only after the temperature his changed accordingly.
NT; you are ahead of yourself; the non-commutative aspect is irrelevant; look at it this way; you can have an infinite number of combinations of LTE's all with a Tave of 288K but none having the same SB energy; this point alone makes the discussion about whether the Earth is in thermal equilibrium with its externalities premature; it is even more problematic when you consider that any 2 LTE's SB energy at any designated time will have a Tave equivalent with any other LTE; for example, when I was pointing out to Will his latest nonsense about the spray from Ray and the uniformity of temp on Earth, I used examples of temp extremities from around the world; at Verkhoyansk, for example which holds the record for the greatest temp range from -68C to +37C, will at some time have a Tave equivalence with countless other LTE's; but over another designated time it will have a vastly different SB energy output; how can you globalise that? Lest you think this theoretical and irrelevant let me give you an actual example of how this regionalism defeats any notion of a global Tave or Teff;
http:www.giss.nasa.gov/research/briefs/shindell_06/ (// excluded)
During the little ice age there was .25% less insolation; the global Tave changed only "a few tenths of a degree", "however, regional cooling over Europe and North America (was) 5-10 times larger due to a shift in atmospheric winds." Given this can we speak meaningfully of a thermal equilibruim for the Earth which is being disrupted by AGW?
"So that the net Flux out doesn't need to be multiplied by 0.7."
Which would be pointless, since you would end up with a planet not in a Steady State, and rapidly warming or cooling.
"look at it this way; you can have an infinite number of combinations of LTE's all with a Tave of 288K but none having the same SB energy;"
A completely meaningless point.
You left out this bit.
Based on climate modeling, we have proposed a solution to the apparent paradox of extreme cold with only a marginally dimmer Sun. I
Test 😀 😉 🙁
Gordon; I have tried to contact Gerlich but have had no response; maybe you could try an e-mail to either, tell them about this thread and see if they respond; by way of info G&T have tried to communicate with some of their detractors, notably dear old eli; they put 5 questions to him;
1 What is the most general formulation of the second law of thermodynamics?
2 What is your favorite exact definition of the atmospheric greenhouse effect within the frame of physics?
3 Could you provide me a literature of a rigorous derivation of this effect?
4 How do you compute the supposed atmospheric greenhouse effect (the supposed warming effect, not simply the absorption) from given reflection, absorption, emission spectra of a gas mixture, well-formulated magnetohhydrodynamics, and unknown dynamical interface and other boundary conditions?
5 Do you really believe, that you can transform an unphysical myth into a physical truth on such a low level of argumentation?
They received no answer from eli; it looks as though it was left to Arthur.
Will ; Test Fail
The non-commutative behaviour is the reason for Motls results
"the non-commutative aspect is irrelevant; look at it this way; you can have an infinite number of combinations of LTE's all with a Tave of 288K but none having the same SB energy"
If he added and averaged the temps appropriately you would only ever get the same SB. You don't apply the SB to each temp and then average, you have to average the temp first.
NT; well, this is a crucial point; what you are saying is that every LTE which averages 288K over a period of time will also have equivalent Teff's for the same period; maybe, maybe not; but what about time intervals within that larger time frame; surely, looked at in that respect Motl is correct.
Cohenite, Motls maths is wrong. It doesn't mean his conclusions are necessarilly wrong, but he needs knew maths to support them.
"LTE which averages 288K over a period of time will also have equivalent Teff's for the same period"
I believe so.
Every Teff will have an inifnite variety of LTE's but they must average to the Teff.
I don't know what you mean about longer time intervals.
So you want Gerlich here? That'll be… Interesting. Someone should bring Deltoid along… Watch the sparks fly!!!
Hang on, did I mean Teff or Tave….
Dinner time calls
Nathan: "So why did you mock Arthur when he said the Earth was not in Thermal Equilibrium with the Sun? And when he said it would be 5000k if it was. He was right."
I thought I have replied to this. He wasn't right. For the earth to be in equilibrium with the sun at this distance a spherical body needs to balance ~ 1366/4 = 341.5 W/m^2 and to radiate that amount a black body needs to be at 278.6K so that is the equilibrium temperature. That is what the radiative effective temperature temperature must be. It's the same for any black, grey, brindle or technicolour spherical body at this distance from the sun.
NT; commutivity is not an issue; look at these calculations;
I have already responded to the paucity of RPH's comments. It is evident that chronologically and spatially there is a energy difference between Tave and Teff such that the Tave of 288K is not a good indicator of the energy budget of the Earth.
I'm going to leave it here I'll think about gavin's earlier suggestion and write something up and pass it front of the nose of an atmospheric physicist before doing anything with it so it won't be peer reviewed but superior reviewed;-)
That link here;
Good on you Jan.
Jan you are mixing your terms up.
This is where the confusion is coming from.
Arthur specifically said thermal equilibrium
I think we need to properly define all the terms.
nathan "Thermal equilibrium is achieved when two systems in thermal contact with each other cease to exchange energy by heat."
That definition is a bit confusing but that happens when net fluxes sum to zero as Arthur says "If it didn't average to zero for a long period of time, the energy of the planet would cumulatively build or decline."
Why are you finding this most simple case of conservation of energy so difficult.
The sun is not in contact with the earth but it's (greatly reduced) heat flux is.
Bob Tisdale says
Cohenite: You wrote, "Bob Tisdale has done some great graphs showing that ENSO doesn't accumulate but the statistical temp effect of the PDO phase changes do."
Which graphs might those be? I think you're mistaken. I rarely graph the PDO. Please enlighten me how I've done that since I believe the PDO is a statistically manufactured aftereffect of ENSO.
This is a graph of the North Pacific SST anomalies versus the PDO.
http://i38.tinypic.com/6p70nk.jpg
You can't find the PDO in the North Pacific SST data unless you standardize the SST residuals of each 5-degree grid square in the North Pacific, north of 20N, then pull the leading principal component from them. And after all that statistical manipulation of data, you believe the PDO drives NINO3.4 SST anomalies. That baffles me. According to your theory, why wouldn't the South Pacific have teh same influence on NINO3.4 SSTs? Just curious.
Hmmm–the core is 466, and still we are no more enlightened.
Never mind, the Wenny Pongs of this world are on their Laborite missions to save the planet and screw the economy, no matter the big holes in the basics of the science and the real world evidence
Sorry Bob; I meant; "Bob Tisdale has done some great graphs showing that ENSO doesn't accumulate but the statistical temp effect of the ENSO (not PDO) phase changes do."
Rightly or wrongly (or lazily) I use the PDO to describe an El Nino dominated period or a La Nina dominated period; in this thread I didn't want to revisit this issue which I think was adequately covered in another thread where the issue of whether El Nino persistence caused upward temp trends, step ups, and counter trends caused by large La Ninas was discussed. I don't have a theory about PDO beyond the fact that there are obviously discernible natural cycles which have dominated temp trends during the 20thC in a fashion which contradicts the CO2 causation.
You seem to have missed Pierrehumberts response.
Climate Scientist Raymond Pierrehumbert made the following comment on Rabett Run regarding the above issue:
I don't have a theory about PDO beyond the fact that there are obviously discernible natural cycles which have dominated temp trends during the 20thC in a fashion which contradicts the CO2 causation.
Oscillations and cycles don't accumulate, by defintion.
Well, there you have it Bob; after all that time spent on discussing how ENSO can produce an upward trend as discussed here;
http://jennifermarohasy.com/blog/2008/10/leading-climate-scientists-don%e2%80%99t-really-believe-their-climate-theory-part-1/#comments
The willful ignorance shown by Will's comment above about oscillations and cycles is astounding; a lengthy period of El Nino will have an upward trend of temp; this may be accentuated by a step-up if the initial El Nino effect is large enough (ie 1976 or 1998); the step-up will have an accumulative effect on the temp record unless it is countered by a sufficiently large series of La Nina; this didn't happen during the 20thC; Bob may or may not care to add to this; personally I don't think your simplistic nonsense deserves it.
In respect from the spray from Ray; this was answered at my October 18, 9.24am comment above; do you read anything?
I'll repeat again, an oscillation or cycle, is, by definition, not a forcing. Where is the extra energy coming from to raise the temperature?
You offer nothing more than a correlation, that can be explained another way, AGW.
No Will, you have to ask yourself, where has the energy gone; from ~ 1940-1976 temps declined; from 2001 they have been declining; where has the energy gone Will?!
SJT: "Where is the extra energy coming from to raise the temperature?"
Stored over up to ~800 years. it's not extra energy just looks like it if your trend analysis period is too short (like 100 years) the long term secular trend since the hollocene optimum is bout -.14K/millennium ths has a few tens of thousands years to run yet.
That's already been answered, there have been various forcings active on climate. Particle pollution tends to cool, such as aerosol pollution that has been addressed in Western countries, CO2 tends to warm. That hasn't been addressed. You, however, have no answers other than correlation and an arugment from ignorance.
SJT: You wrote, "I'll repeat again, an oscillation or cycle, is, by definition, not a forcing. Where is the extra energy coming from to raise the temperature?"
Why does there have to be a forcing to make SSTs and global temperatures vary? Refer to "Sources of global warming in upper ocean temperature during El Nino", by White et al, 2001. The abstract closes with, "Thus global warming and cooling during Earth's internal mode of interannual climate variability arise from fluctuations in the global hydrological balance, not the global radiation balance. Since it occurs in the absence of extraterrestrial and anthropogenic forcing, global warming on decadal, Interdecadal, and centennial period scales may also occur in association with Earth's internal modes of climate variability on those scales." And the Discussion and Conclusions ends with, "Yet, the fact remains that global warming and cooling occurs on interannual period scales in the relative absence of any known extraterrestrial and anthropogenic forcing on these scales. This may come as a surprise to many readers. It suggests that global warming and cooling on decadal, interdecadal, and centennial period scales can also occur in the absence of extraterrestrial and anthropogenic forcing."
Here's a link:
http://meteora.ucsd.edu/papers/auad/Global_Warm_ENSO.pdf
Can't you understand English. They aren't saying that there is no AGW, they are saying that the PDO can cause global warming due to positive feedbacks. The same positive feedbacks that are the cause of concern with AGW.
cohenite "Gordon; I have tried to contact Gerlich but have had no response";
I did too…no response yet. Maybe I'll try T. Sometimes the spam filters are too strong and ordinary messages don't get through.
SJT: "They aren't saying that there is no AGW, they are saying that the PDO can cause global warming due to positive feedbacks."
written in 2001 Spencer has an update for you that says PDO and other (apparent) oscillations can look like positive feedback but isn't. More like ringing in an under damped system
It's all to do with time scales.
Jan, you made this up
That"s just something in your head.
I'm not finding it hard, you are just mixing your terms up. You did it again. You mixed "thermal contact" with "contact".
You need to properly define what you are talking about. I guess you will when you summarize your version of the Misko theory.
It's strange how people on the Landshape blog were telling you that the Misko theory was a grey body problem, then I did and you acted as if you had no idea what I was talking about… If you play the pedant game, I will play it right back. You're so loose with your definitions that it'll be rather good sport I think.
Yes, and Misko fails badly when trying to explain the very high temps in the Cretaceous etc… Yes… That's one thing he needs to sort out.
I think it was just about at that realisation that Arthur gave up.
Fair dinkum Will; Bob has given you one reference to explain how the Earth's dynamic climate system can generate heating and cooling without external forcing; the Tsonis paper is another; this focuses on the GPCS, which occurred in 1976, and ushered in a 30 year era of El Ninos and upward temp trends; Tsonis doesn't speculate about the cause but McPhaden and Zhang and Guildersen and Schrag and McLean and Quirk all look to partial cessations in deep water upwellings; the shallow meridional overturning circulation which weakened following the 1976 event, has rebounded since 1998; no amount of arm-waving will make this disappear; it is a genuine internal climate mechanism which puts the lie to the AGW thermal equilibruim idea that for temp variation external forcing is necessary; at least your reaction is better than that savant, Tamino, who simply bans discussion of this effect.
As to aerosols; IPCC doesn't have a clue; they readily admit their level of SU is abysmal, sorry, low; and no wonder; the conventional 'wisdom' which you parrot, is that aerosols cool the troposphere and warm the stratosphere; well Ramanathan et al finds that the warming effect from areosols is > than from GHG's, while luke's favourites, Cai and Cowan, have a bet each way, and find that aerosols warm the subtropics while cooling the "off-equatorial region";
Tsonis says his papers have nothing to do with AGW.
"Thermal Equilibrium"??? Not again. Have you learnt nothing? No one claims the earth is in a state of "Thermal Equilibrium".
You nong Will; if there isn't thermal equilibrium how do you measure AGW ?
NT; I see you can't resist sniping at Miskolczi; the old chestnut that his theory won't accommodate historically extreme conditions; this is a red herring; Miskolczi's theory simply says that the optical depth for the internal Kirchhoff conditions is pretty much set; increases in CO2 will be mached by declines in water; RH is declining; some points; you mentioned the Cretaceous; this Berner derived graph shows no correlation between the temp and CO2 levels of the Cretaceous;
http://www.junkscience.com/images/paleocarbon.gif
At Niche there is a new thread about the internal compensating mechanisms based on Miskolczi which maintain the optical depth; since CO2 is a non-event climatically, it is evident that atmospheric water levels were responsible for the Cretaceous climate; the Kump and Pollard paper, which I have provided to you previously, considers this; they say "Our climate simulations show that reduced bilogical productivity (low CCN abundance) provides a substantial amplification of CO2 induced warming by reducing cloud lifetimes and reflectivity;" in effect the optical depth of the atmosphere was greatly increased by declining water vapor; Arthur's comments show he has no idea about this; he says;
"higher surface temperature means more water vapor (specific humidity will increase), and that further increases the atmosphere's absorption of thermal radiation, at least in the regions where water vapor levels change. Snow and ice melts. Clouds respond in some fashion to the changing temperature and humidity profile in the atmosphere." (12.32 am)
This is utter bunk; "clouds respond in some fashion"; yes well, no doubt they do; a point to note about our discussion about SH and RH; it is possible for rain falling through warm, humid air to be cold enough to lower the air temperature to the dew point, thus condensing water vapor out of the air. Although that would indeed raise the RH to 100%, the water lost from the air (as dew) would also lower the SH.
Cohenite, have you gone and read any of the opposing views about Misko?
Strangely enough they tend to revolve around his application of Kirchoff's Law (something that we discussed at length here, when I found that text book saying that you can't use it when the emitted radiation is of a very different wavelength to the absorbed radiation), what it means to be in Thermal Equilibrium (which AGW actually assumes we are not in, certainly not with respect to the Sun anyway), and that his virial theorem is just wrong.
Remember in the Cretaceous and in earlier hothouse climates the sun was cooler, this last few thousand years will be the warmest for the Sun.
That Berner graph is next to useless. We know (and it has been repeated thousands of times) that the climate is controlled by many many more factors than CO2, so to expect to see a genuine correlation between CO2 and temp is, well, silly.
If the Cretaceous had drier air than now (ie lower SH) then there is an even bigger problem as you need that water to make it that hot. Clear skies aren't enough.
Did you actually make a mistake on your analysis of their work? Should their work, if there were fewer clouds about, actually have said that SH would increase in the Cretaceous?
"This is utter bunk"
Cohenite you told me that the ONLY thing warmer air could spend it's heat on was evaporating water. So how can you say that Arthur's statement is bunk when you would actually have it make more SH.
And you still don't really get the RH thing. Cloud formation requires a lot of different things, a condensation nuclei. RH can (theoretically) exceed 100% without rain. Apparently clouds even need cosmic rays.
Have you compared graphs of RH and SH. This should actually give you a good idea of whether or not Global Warming is happening. I think you will find that SH is more or less stable, and RH declining. That implies temps are going up. Perhaps soon we'll see SH increasing – then we will be in trouble.
"Our climate simulations show that reduced bilogical productivity (low CCN abundance) provides a substantial amplification of CO2 induced warming by reducing cloud lifetimes and reflectivity;"
It is appears there is only one set of climate models you don't believe.
Ok, where are the graphs showing SH is increasing?
Phew; what a wind up in the download to get to where we are at now.
Jan; I reckon you like Arthur should start by defining your terms then do an outline similarly no Chg.'s then worst case/ best case structures.
Out of interest I Goggled RH and SH 2008 thinking more hog wash and red herrings but I just happened to open this link
http://rankexploits.com/musings/2008/humidity-time-series-where-to-find/
there was Arthur Smith (Comment#3533)
June 23rd, 2008 at 12:46 pm
and Lucia! Read on –
BTW I met a charming young lady today who thinks she is a sceptic after I advance my usual market survey but guess what; her handsom boyfriend became increasingly aggitated with her answers because he works for CSIRO in information and knows about the current science.
What started me thinking about it again today was this girl has just crossed central Asia on a pushbike and I expected her to have the edge on a few of us at ground level and at considerable altitude..
This paper redefines global warming. But not in a weird way. Of additional equations related to Kirchhoff's law, constraining the atmosphere to be in thermal equilibrium with the surface, Miskolczi writes:
See, there's his first mistake. The atmosphere is most definitely not in thermal equilibrium with the surface.
From Climateaudit on miscolzi
I stopped at Equations 5 and 6 as they seemed to be a misapplication of Kirchoff's theorem.
To apply Kirchoff's theorem you have to assume that the atmosphere is in thermal equilibrium with itself and with the earth's surface. But it's not. At best it can be approximated to be in local thermal equilibrium – ie. everything remaining at the same temperature. But there is always a flow of heat from the surface to the top of the atmosphere.
Therefore, it is incorrect to say that the back radiation (Ed) equates to the radiation from the surface absorbed by the atmosphere (Aa). This is what is assumed to get equations 5 & 6. Equation 5 is saying that (assuming P and K are really small) IR radiation to space (Eu) equals the solar radiation absorbed by the atmosphere (F) and is not at all affected by the amount of heat absorbed from the ground near the surface. This seems to be obviously wrong.
Perhaps this doesn't affect the rest of the paper… 😕
http://www.climateaudit.org/phpBB3/viewtopic.php?f=4&t=161
The whole basis of his paper is wrong.
Here's a graph from Gavin's Link
http://i30.tinypic.com/fdsmc2.gif
I guess other contributors may have tried their own RH measurements, dewpoint and vapour analysis etc but it goes without saying that we are handicapped by the instruments of old when it comes to longer time series. It's definitely an art not a science when it comes to calibration in more extreme conditions too.
Now gavin, I'm very disappointed; you've gone to a blog to get some evidence; have you no shame? You should also have read a little further than Arthur's comment;
Well, you first NT; what does it mean?
"The whole basis of his paper is wrong." Just hopeless. Miskolczi has had more empirical verification in one year then Hansen and IPCC have had in 20 years; which wouldn't be hard since Hansen and IPCC have had none.
Loks like SH is going up close to the surface and dropping in the Stratosphere. I think Arthur said 300mB was lower stratosphere.
The author of the graph (Nick Stokes) says he shifted the data so the present day all reads as 0. So the data show the change from today (though not today, today but rather in June or something).
So the water content (SH) of the lower atmosphere is increasing and water content for higher in the troposphere is fluffing around (was higher in the 50s, but lower between the 60's and 90s, and the lower stratosphere SH has been slowly dropping.
And we also know that RH has been dropping, so that means that the atmosphere is actually capable of absorbing more water than it has, hence we could probably expect the atmosphere to suck up more moisture and enhance our greenhouse effect.
Don't know when that will happen though, and perhaps because the rate of SH increase hasn't matched to potential it could explains why the last few years haven't been hotter? Maybe if the RH stabilised (hence SH is going up in line with temp) then we would really start seeing some toasty warm times…
SJT,
Misko does seem to be somewhat… ummmm… Wrong?
And another thing; Miskolczi has been completely open and transparent with his paper and in responding to the usual vitriol from the usual suspects; his response at the Niche thread is exemplary to provocation from BPL and sustained critiques from Neal and Stokes; compare his behaviour to that of egos like Mann and Hansen and Amman and Wahl.
Nick does caution, however:
[from AR4] " Changes in upper-tropospheric water vapour in response to a warming climate have been the subject of significant debate.
Due to instrumental limitations, long-term changes in water vapour in the upper troposphere are difficult to assess.
The NCEP reanalysis data is not the only source, and probably not the best."
Maybe you should find your own SH data?
NT; if greenhouse theory was working SH wouldn't be falling at any level and neither would RH. If the atmosphere hasn't been sucking it up already why is it going to suddenly start doing it?
"Find my own SH data"
Right; I'll power up the balloon and spend the next month at 5km up with a bucket.
Miskolczi
Awww, this one's an easy one. There may be other mistakes, but clearly the author errs in point (g) on page 4. While the atmosphere is gravitationally bound to Earth, it does not orbit the Earth, in the sense that its kinetic energy is half the gravitational potential energy. If this were true, wind speeds would be 8 km/s on the surface! It therefore does not follow that "in terms of the radiative flux Sa=sigma T^4 represents also the gravitational potential energy."
http://209.85.173.104/search?q=cache:XCLouKrwwMwJ:www.physicsforums.com/showthread.php%3Ft%3D232818+Miskolczi+wrong&hl=en&ct=clnk&cd=3&gl=au&client=firefox-a
No wonder he is mostly just ignored, and NASA wouldn't publish him.
Will; pathetic; the VT, which your smart-bum link refers too, as used by Miskolczi, is addressed at the Niche discussion; the particular red herring your nit-wit raises is addressed at items 124 onwards; things start moving when Franko comes in at about 160.
As I said above Miskolczi's optical depth has been independently verified; AGW, IPCC and Weart and Smith's optical depth hasn't; which is good since you would be a fried turkey.
Cohers, I thought SH decline high up was fine, why would water accumulate in the stratosphere? RH can do what it will…
"As I said above Miskolczi's optical depth has been independently verified; "
Doesn't matter if his maths is wrong. Anyone can guess a cvorrect answer
Cohenite: You were warned.
Miskolczi, Motl et al only run well in blog'sphere with arguments that repeatedly bounce off the hard shell of classic physics and math. You should know more than most that laws have to be interpreted by experts so they may properly reflect community expectations and there is a good democratic aging process with all new legislation.
Further, we have a general problem with individuals doing their own thing in any discipline. Also to get anywhere we must each stand on the shoulders of giants who have gone before.
Build your team thoroughly before launching your next attack and don't rant until its over hey.
Don't you worry about me gavin, just keep in touch with that charming young lady, and let us know how things pan out with her handsome boyfriend.
NT; when theory won't fit the facts, what's the first thing we are going to screw up?
With the current speed of AGW, lots of things are going to vaporize besides fuels and shares
been a long day
So, let's finish with a summary;
1 Average global temperature has no meaning
2 There is no meaningful connection between Tave and Teff
3 The 'greenhouse' effect of GHG's is miniscule
4 There is capacity in the global climate system for temperature trends which do not require external forcings; ie ENSO
5 Miskolczi's atmospheric model has had independent empirical verification
6 The latest attempt to verify the Smith/Weart/AGW atmospheric model by Santer et al is a dud;
http://rankexploits.com/musings/2008/lets-apply-the-method-in-santer17-to-gmst-part-1/#comments
The search continues for a verified manifestation of AGW.
I will only adress point 6 as the rest are… well… your opinion and not worth much.
Note that Lucia makes no attempt to discredit the findings of Santer. What she does is a further experiment, that is take their work which was for the Tropical Troposphere and see if it works for the whole Globe. I am not sure if this really serves a purpose and your claim that Santer et al is a dud based on this is ill founded. You are allowing you lawyer/partisan views affect you objectivity.
I think the current financial crisis will end the carbon trading schemes for while… No fear on acting too quick anymore.
Cohenite, it's also disappointing that you would attempt a summary like that. I thought we had achieved a reasonable level of debate and for you to characterise it in that fashion is, well, breathtaking. You seem to be ignoring the actual discussion that took place and attempting to restore your personal paradigm.
Let's look at some other results form this discussion. Lets even the balance…
Most of the disagreements were due to poorly defined terms.
Misko 2008 uses Kirchoffs Law and the Virial Theorem incorrectly and deduces that the atmosphere is in orbit around the Earth.
Jan ridiculed Arthur's attempt, but in the end couldn't keep track of whether he meant Thermal Equilibrium, Thermodynamic Equilibrium, or Radiative Equilibrium.
You yourself failed to understand that before anything in maths, commutivity comes first.
And finally you and Jan ignore the multitude of mathematical proofs of the Greenhouse Effect that have been produced in favour of Misko… This is not 'skepticism'.
It has a meaning, as defined. Without an appropriate definition, it has no meaning.
Miskolczki's paper has so many errors, it is a wonder he found anything that would publish it.
The Greenhouse effect is significant, without it we would be living in an ice age.
Lucia is incapable of performing any serious statistical analysis. Her comparison of "Centuries" was of a high school standard.
Time October 19, 2008 at 10:46 pm
This is so elementary that I am sure you are misinterpreting something. Possibly the method of integrating assuming spheres of thickness dr in "stationary orbit" around the center of the earth?
We are all orbiting the center of the earth after all with a constant rotational velocity.
SJT" If this were true, wind speeds would be 8 km/s on the surface!"
actually PE/KE = -2 holds very well on the earth without any need for 8km winds.
And his virial term does not relate to Clausius Virial theorem it was just a measure for ratio for upward radiance from the surface to upward radiance from the atmosphere. His value for the virial term was empirically determined not theoretical and different for as for earth.
Anna, these are not my personal conclusions, I am reporting form what I read here:
It was in the spirit of Cohenite's 'Summary'.
In my own reading of Misko 2008, it does appear that he has used Kirchoff's Law wrongly…That was enough for me.
You are a big believer in climate models, Cohenite, I have seen you refer to the results of some models just over the past few days.
The funniest thing SJT is this:
"lucia (Comment#5873) October 16th, 2008 at 1:37 pm
Santer examines a different metric: "Temperature Trends in the Tropical Troposphere". (Say that three times fast! 🙂 )
I am applying their method to GMST. So, the numerical values for trends will be different because the tropical troposhere is expected to warm at a different rate than the global mean surface temperature.
So…. I am not disputing the actual results in Santer. I have a few quibbles which I will get to later. But basically, I am seeing what results are obtained if we apply the method to a different metric: GMST.
I can do this fast because I have the GMST data. Plus, the paper is mostly straightforward, both in the things that appear correct (much of it) and the things that I have a few misgivings about."
I wonder if Cohenite actually read the whole post?
So that's how he came up with the right answer for his model. Create a formula, then find out what the factor is that makes it match the observations.
SJT: "So that's how he came up with the right answer for his model. Create a formula, then find out what the factor is that makes it match the observations."
No that is not how it works Miskolczi did the observations and that was al he initially presented to TellusB this was withdrawn. The formulae and derivations were only added after a Hungarian astrophysicist insisted on his adding a theoretical basis for discussion. Perfectly standard procedure for empirical science do the experiment take the observations develop a theoretical basis for the observations.
It is an inane comment of somebody who does not understand how one does calculations. There is a comment further down by DavidLH in the link you gave that makes this clear.
It is the chicken little effect, quotes floating around like this. I suppose the internet encourages "a liitle knowledge", which is a bad thing.
SJT: "The Greenhouse effect is significant, without it we would be living in an ice age."
Haven't you understood anything discussed here?
The equilibrium temperature of this planet is set by the suns parameters and our distance from it. For earth that is a toasty 279K this cannot change due to anything we do on earth :- Kirchoff's law. According to NASA data not only is the effective average temperature, as measured by satellite (ERBE), of earth at that equilibrium temperature so it is for Venus and for Mars.
NT; fairly peurile; and cherry laden; lucia will come around when she sees she's been sold a pup; I like Bill Illis's comment at 5905. As to the GMST/tropics red herring;
1 If models can't match GMST how can we rely on their validity for a smaller area; this is sort of like the AGW complaint about Koutsoyiannis in reverse.
2 Santer says "To facilitate the comparison of simulated and observed tropospheric temperature trends, we calculate synthetic MSU T2 and T2LT temperatures from gridded, monthly mean model data using a static global-mean weighting function." Did you even read Santer NT? But how about that, they use a "global-mean weighting function"; kinda makes lucia's exercise valid.
3 Santer's data is rubbish; it effectively ends at 1998 and is a GCM regurgitated mish-msh; observed data my eye; observed sitting in front of the computer screen.
4 Santer's error bars; well lucia got that right.
My summary;
1 Are Tave and Teff commutitive?
2 Is Teff subject to diurnal and spatial and surface type qualifications?
3 Did NT read the Algernon calculations which show a divergence between Tave and Teff of up to 10%?
If Tave and Teff are commutitive how can they be so divergent?
AGW requires an ave global temp because it is essential for AGW to compare a pre-AGW condition when there was a radiative balance based on the BB temp of 255 + the GH effect of 33 (thanks Arthur!). The AGW opaque atmosphere then cranks up with additional CO2 to create a radiative disequilibrium with consequent thermal disruptive effects on ave global temp. It is contradictory to say that AGW does not require an equilibrium base for comparison with the effects of AGW.
Miskolczi and VT and Kirchhoff; Kirchhoff is limited to radiation equivalents, but since M is talking about up LW, down LW and TOA outgoing LW he is talking about wavelength equivalents. The VT dispute and the relationship of the atmosphere with the surface is thrashed out at the Niche discussion; much of the misundertsanding is that M's data, HATCODE is different from K&T's 1997 stuff which gives a different optical depth to M's data; as I say M's data has been verified; K&T's has not only not been verified it is being disproved everyday, Your complaints about M are nothing more than cheapshot ad homs; M would have to be the most discussed concept in AGW; if you guys are so concerned do a Neal King even if, like him, you end up missing the point, you will still add to the discussion; I know you won't but from comment 123 onwards the VT is discussed and resolved.
I don't even know if it's an issue. He has come up with a formula, and plugged in the empirical values to make it work. Of course it gives the right answer.
As my uncle says, it's like giving a baby razor blades to play with.
Cohenite you still don't get the commutative commment do you.
Motl used ordinary averages to get his four climate zones, that is (T1 +T2 + T3 + T4)/4 = Tave.
But when he did his SB calcs he used (T1/4) +(T2/4) +( T3/4) +(T4/4)
It is just wrong.
As to whether Teff and Tave are commutative, it doesn't matter. What matters is that when something is non-commutative you compute the equation 'forward'. You don't mix the orders up or do divisions before additions or powers before averaging. If you do the processin the proper order it will be fine.
I'll show you again
[(T1+T2+T3+T4)^4]/4 x SBconstant
not [(T1^4)/4 x SB constant + (T2^4)/4 x SBconstant + (T3^4)/4 x SBconstant + (T4^4)/4 x SBconstant ]/4
The above does not give you Teff. It gives you the average of 4 discrete black bodies.
What does 'Cohenite' mean anyway?
Anna V
Thanks… That's very nice… Did you note that the agreement there was that Misko was wrong? DId you have a point? Do you think Misko is right? Or is this just an inane comment from someone who can't read?
SJT, I knew they would cling to their anti-Greenhouse Effect understanding no matter what we said.
NT; cohenite means banger of head against brick walls; at least in this context; you haven't answered the question; I agree it doesn't matter if Tafe and Teff are commutative; personally I think they are; how could they not be when the Tafe is the basis of the SB radiative energy; but Motl is big enough to defend himself, I'll put the query to him; in any respect how is it that Algernon has found such divergence between Tafe and Teff; remember, Algernon is not doing what Motl did; he is doing what Pielke describes in his paper; which is taking into account the spatial differences with SB and then comparing them with the Tave over the same ground; he gets a 10% divergence; can you fault his calculations?
STOP THE PRESS!! Glaciers growing in Alaska!!
http://www.prisonplanet.com/global-cooling-alaskan-glaciers-grow-for-first-time-in-250-years.html
Prediction of reactions from realclimate and the AGW crowd:
1)It's just a long La Nina.
2)Models predicted that.
3)It's a plot by the oil and tobacco companies.
4)Where's Alaska?
5)Yeah…but the Arctic's still melting.
6)It's aerosols.
7)It's soot.
8)The polar bears are responsible.
9)Palin's behind this.
10)What bet?
Then be careful baby
Gordon; please don't bother us with blog views on ice
http://nsidc.org/arcticseaicenews/index.html
Gavin…your link is about 'sea ice', I'm talking about Alaska and it's glaciers. Surely I don't have to explain the difference between ice floes and glaciers.
Don't like blogs, how about the University of Alaska Geophysical Institute:
http://www.farnorthscience.com/2007/07/10/ak-sci-forum/icy-bay-glaciers-advance/
In case you haven't been keeping up with news on the Arctic, it's the Atlantic side that's getting most of the melting and it's due to the Atlantic Multidecadal Oscillation. The Siberian side, and obviously the Alaskan side are cooler. The AMO is bringing warm water into the Arctic region and that is known to melt sea ice and allow it to flow out of the Arctic. It also affects Greenland and Iceland.
Time October 20, 2008 at 9:28 am
I am sorry NT, but if we are starting to exchange snide remarks, David LH says:
"If you find primary literature that supports your contention, please cite it to pursue this further. Otherwise I will assume Miskolczi is correct."
as also gdp further down in your link on the same error on page 4 that you quoted
"Sorry, but your reasoning is flawed, on two points:"
My comment was on this error that is so trivialy not sol that even people who disagree with the Milkoswski had to defend him on this point.
This proves to me that you just grab randomly "against" points without looking to see whether they are valid or refuted further down.
I do not know if the theory by Milkowski is correct as it is not my field and I do not intend to delve into thermodynamics to the extent that is needed to have a clear opinion.
anna v; your reserve is commendable; in this AGW debate there are too many ideological, half-baked opinions floating around; with that caveat let me put mine; Miskolczi's atmospheric model seems to have achieved a number of verifications such as declining atmospheric water levels and his optical depth; I can't think of one verified AGW component.
Anna V, why are you picking on me?
You just randomly assaulted me, I explained my case (I was using trivial arguments back at Cohenite who was making ridiculous assertions about what had been discussed) and now you attack again… Why?
Ok, do you believe Misko 2008?
Did you read all of that forum? The host clearly states several reason why it is flawed.
I myself deduced that his use of Kirchoff's Law is wrong (Google "Grey Body Assumption")
Why would I care what you think?
So why are you attacking me?
I have presented my case, too bad if you don't like it. Make a case of your own.
Cohenite, you faux humility and reserve is refreshing fraudulent. Yet again.
" I can't think of one verified AGW component."
There's an obvious reason for that.
NT; condescension is the last and only refuge of the snob; so try to resist temptation; what about Algernon? And now that Santer is in the same room as Mann, Sherwood, Ammann and so on and so forth, feel free to present that verification.
SJT: Excuse the delay in responding to your (October 19, 2008 at 12:59 pm) comment, which was, "Can't you understand English. They aren't saying that there is no AGW, they are saying that the PDO can cause global warming due to positive feedbacks. The same positive feedbacks that are the cause of concern with AGW."
I never said or implied that they were saying there was no AGW. I was not discussing AGW. Nor was I discussing feedbacks. My comment pertained to your insistence that there needs to be radiatve forcings to make temperatures vary, which that paper contradicts by concluding that "global warming and cooling on decadal, interdecadal, and centennial period scales can also occur in the absence of extraterrestrial and anthropogenic forcing."
Additionally, the paper I linked discussed El Nino and La Nina events, not the PDO.
"condescension is the last and only refuge of the snob; "
I am not going to bother anymore Cohenite.
This post has certainly been educational for me, I have learnt quite a lot, and I sincerely hope it has been for you too.
Comment from cohenite
"Miskolczi's atmospheric model seems to have achieved a number of verifications such as declining atmospheric water levels and his optical depth; I can't think of one verified AGW component."
Do you know the poem by Pooh Bear?
"the more it snows,
the more it snows
the more it goes on snowing"
That is the type of AGW verifications we are offered:
"the more it warms,
the more it goes on warming"
except not because of anthropogenic CO2
Bob; this thread has gone on too long, but I thought you might be interested; Watts previews a new Spencer paper which looks at climate being largely a product of internal forcings; he uses the PDO and associated cloud cover flux as the agent of temp trend and climate variation;
http://wattsupwiththat.com/2008/10/19/new-paper-from-roy-spencer-pdo-and-clouds/#more-3721
I know you think the PDO/ENSO is more than just terminology; do you want to get Spencer to comment; I certainly would be interested on his views about PDO being a residual of ENSO.
Bickers says
People – pleased find the time (you'll need it) to read what I believe is a seminal 'paper' addressed to John McCain that is quite brilliant in it's demolition of the AGW scam:
http://www.americanthinker.com/2008/10/an_open_letter_from_the_viscou_1.html
Cohenite: Beat you to it. Notice my question to Dr. Spencer at WattsUpWitthThat and his reply. I've had my say, and I didn't feel it appropriate to carry it any further.
Bickers, the American Thinker paper by Monckton is superb. A brilliant piece of writing.
It would also pass as a summary for this thread with +540 posts, namely–we do not know enough with a degree of that warrants buggering up economies.
Those scientists that do say so, should hand back their citizenship documents and go and live in China an India and if they can win them over first they might earn a smidgin of credibility.
I can't think of one verified AGW component.
Yes Malcolm, that is good link of Bickers; Monckton is good value.
As to Will; why don't you, or one of your brothers in arms, put forward a genuine AGW indicator, so we can all have a little chat afterwards, and then perhaps a Bex and a nice lie down.
"and then perhaps a Bex and a nice lie down."
Not without a cup of tea.
Well then SJT why dont you bugger off to China and/or India and persuade them of the AGW idiocy, because without them the game is up–we would be committing economic suicide for no reason.
Thats what I like about the rationality of the white coats.
Bob Tisdale "Notice my question to Dr. Spencer at WattsUpWitthThat…"
What happened to their website? I can't reach them at wattsupwiththat.com.
What is up with that? 🙂
anna v "I do not know if the theory by Milkowski is correct as it is not my field and I do not intend to delve into thermodynamics to the extent that is needed to have a clear opinion".
Obviously, most of the pro AGW scientists don't delve into it to that degree either, especially the collection of mathematicians, computer programmers, theoretical physicists, and geophysicists at realclimate. That doesn't stop them not only offering an opinion, they seem to think it qualifies them to ridicule other scientists of repute.
I appreciate your honesty, Anna.
NT "Anna V, why are you picking on me"?
1)He who lives by the sword shall die by the sword.
2)He who lives in glass houses should not cast stones.
3)He who cannot stand the heat should stay out of the kitchen.
4)He who cannot play with the big boys should get off the field.
5)He who can't take it should not dish it out.
6)All of the above
Please select one of the above.
Just kidding NT. I know all those barbs you have shot at me were done in jest, especially when you ran over to Deltoid to report on my more outrageous comments.
On thermal equilibrium and Kirchhoff's law, just to state the facts as clearly as possible here, one very last time:
(1) Jan Pompe has a definition of thermal equilibrium, that a body is in thermal equilibrium if its net exchange of energy with its surroundings is zero.
(2) Kirchhoff's law (grey-body form) applies under thermal equilibrium of a system with its radiation field: "At thermal equilibrium, the emissivity of a body equals its absorptivity."
(3) In reality thermal equilibrium is unusual; this form of Kirchhoff's law can be seen not to apply in many cases. For example, a photodiode or photovoltaic cell absorbs a quantity of light and converts some of it into electric energy; whatever it emits is less than it absorbed, yet there is zero net energy change with its surroundings assuming it is at a steady temperature (meeting Pompe's definition of equilibrium). Conversely, an LED (or lightbulb) emits light, while receiving only electricity as input. A gas laser receives one form of light as input, and produces coherent light as output, but the input radiative energy is significantly greater than the output, and they are at carefully chosen and differing frequencies where there is no relation between the two emissivities (and absorptivities); nevertheless, the combined laser and thermal output of the laser is exactly equal to the input energy, as once again it forms a steady-state system that Jan Pompe would have you believe is in thermal equilibrium.
(4) I'll quote from the very introduction of one standard text on thermodynamics, P.C. Riedi's "Thermal Physics", 2nd Edition, Oxford Science (1988) – p. 3
"When the properties of a thermally isolated system become independent of time the system is said to be in thermal equilibrium. […] The approach to equilibrium would depend on the nature of the experimental system but the properties of all systems in thermal equilibrium are contained in the laws of thermodynamics. The simplicity and the universal character of the thermal equilibrium state makes it of great theoretical importance although it is clear that only carefully prepared experiments are in general in thermal equilibrium with their surroundings.
The equilibrium state should be distinguished from the 'steady state' often considered in the study of transport properties such as thermal conductivity. In Fig. 1.1 the thermal reservoirs are at temperatures T_R1 and T_R2 and the temperature along the metal rod will quickly seem to become independent of time. The rod is now in a steady state – the simplest type of transport situation – but the only possible equilibrium state for the isolated system of reservoirs and rod is when T_R1 is equal to T_R2."
In my model (and in essence, for the real Earth), the planet is in exactly the position of a portion of Riedi's metal rod, situated in between one large reservoir (the Sun) at a very high temperature, and another large reservoir (the rest of the universe) at a very low temperature. This is a steady state situation, it is not thermal equilibrium. Kirchhoff's law in its simplest form does not apply.
Measurements of the Earth's absorptivity and emissivity at the relevant wavelengths, as has been repeatedly noted above, quantify the stark contrast between the fraction of incoming short-wavelength radiation absorbed (about 69 or 70%) and the ratio of outgoing long-wavelength radiation to that expected from a black body (95-100%). Snow, ice and clouds all are quite highly reflecting for visible light, but absorb (and emit) infrared almost as well as a black body.
Pompe's natural temperature of 279 K, claimed from the misapplication of Kirchhoff's law in this situation, applies only to a planet for which the short-wave and long-wave emissivities (and absorptivities) happen to coincide – a "gray body" world. That is not the world we live in. If you insist on comparing the temperature of our planet with a hypothetical "gray body" planet, I suppose you can do that, but don't claim it has any relevance to the magnitude of the greenhouse effect!
"For example, a photodiode or photovoltaic cell absorbs a quantity of light and converts some of it into electric energy; whatever it emits is less than it absorbed, yet there is zero net energy change with its surroundings assuming it is at a steady temperature (meeting Pompe's definition of equilibrium). "
Of equilibrium yes but thermal equilibrium no.
Stop it with the strawman arguments already.
People only resort to strawman if they can't refute an argument as it stands.
you are showing that my friend was right that you would expend and extraordinary effort defend your boo boo. You have even taken to building scarecrows of straw now.
http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter3.pdf
Smith: "Pompe's natural temperature of 279 K, claimed from the misapplication of Kirchhoff's law in this situation, applies only to a planet for which the short-wave and long-wave emissivities (and absorptivities) happen to coincide – a "gray body" world."
Pure crap Smith for thermal equilibrium or even your steady state the heat energy in = heat energy out irrespective of wavelength.
He's having a lot of trouble pinning you down to what you actually think in scientific terms, not terms that mean whatever you want them to mean.
That's a start.
From this link.
http://oceanworld.tamu.edu/resources/oceanography-book/radiationbalance.htm
Notice also that the amount of infrared energy emitted at the top of the atmosphere (235 W/m2) must equal almost exactly the amount of solar energy absorbed by earth (342–107 W/m2). The small difference, about a watt per square meter, leads to global warming or cooling.
Arthur Smith "Snow, ice and clouds all are quite highly reflecting for visible light, but absorb (and emit) infrared almost as well as a black body", then, "….a "gray body" world. That is not the world we live in".
I claimed in an earlier post that you addressed only a small part of the G&T paper. I note as well that you did not mention CO2 in your statement above about black body radiators, but I presume you include water vapour and CO2 in that category.
Here's what G&T say about that on page 12:
"For instance in many calculations climatologists perform calculations where idealized black surfaces e.g. representing a CO2 layer and the ground, respectively, radiate against each other. In reality, we must consider a bulk problem, in which at concentrations of 300 ppmv …. N = 8.00e6 CO2 molecules are distributed within a cube V with edge length 10 microns, a typical wavelength of the relevant infrared radiation. In this context an application of the formulas of cavity radiation is sheer nonsense.
It cannot be overemphasized that a microscopic theory providing the base for a derivation of macroscopic quantities like thermal or electrical transport coeffients must be a highly involved many-body theory. Of course, heat transfer is due to interatomic electromagnetic interactions mediated by the electromagnetic field. But it is misleading to visualize a photon as a simple particle or wave packet travelling from one atom to another for example. Things are pretty much more complex and cannot be understood even in a (one-)particle-wave duality or Feynman graph picture.
On the other hand, the macroscopic thermodynamical quantities contain a lot of information and can be measured directly and accurately in the physics lab. It is an interesting point that the thermal conductivity of CO2 is only one half of that of nitrogen or oxygen. In a 100 percent CO2 atmosphere a conventional light bulb shines brighter than in a nitrogen/oxygen atmosphere due to the lowered thermal conductivity of its environment. But this has nothing to do with the supposed CO2 greenhouse effect which refers to trace gas concentrations. Global climatologists claim that the Earth's natural greenhouse effect keeps the Earth 33 C warmer than it would be without the trace gases in the atmosphere. 80 percent of this warming is attributed to water vapor and 20 percent to the 0.03 volume percent CO2. If such an extreme effect existed, it would show up even in a laboratory experiment involving concentrated CO2 as a thermal conductivity anomaly. It would be manifest itself as a new kind of `superinsulation' violating the conventional heat conduction equation. However, for CO2 such anomalous heat transport properties never have been observed".
They don't mince words, do they…'sheer nonsense'?
If you read the next page, they talk about much of the greenhouse theory being based on work that was done before 1925, when Planck brought out his quantum theory. The IPCC has made several gaffes like that in order to make their theories work, and I'm sorry to see a bright young physicists like you defending them.
Don't believe a word of it, it's all "Sheer nonsense".
SJT: "He's having a lot of trouble pinning you down to what you actually think in scientific terms, not terms that mean whatever you want them to mean."
What part of this statement of his do you think he doesn't understand?
That makes perfect sense, and he says that, the earth is in a "Steady State".
If you look at the link I just provided, outgoing radiation nearly matches incoming. It's that slight difference that's of interest.
Comment from Jan Pompe
Jan Pompe: "What part of this statement of his do you think he doesn't understand?"
This is slightly Off topic.
We have been forced ( pun intended) to be looking at energy balances as surface effects: Watts per meter squared. Nevertheless, the earth is a three dimensional volume, with heat capacities , on the one hand, inherent volcanic heat ( the temperature goes up the lower one digs in the mantle, and even at shalow basements it is around 14C, very close to the "average temperature"), and gravitational tides that also input bulk energy. The oceans are cold, but they also are heated from the volcanic activity and the higher mantle temperatures.
If we are looking at "long times" these should be taken into account, in my humble physicist opinion, because they also build up maybe like a slow fuse.
You swine Will; I clicked on your link before I realised it was to that travesty, AR4; my computer is in thermo-garbage equilibrium, none out, none in; with that amount of garbage coming in it heated up dangerously; while I was waiting for it to cool down (accordin to the lag principles of Trenberth, pro-rated down to my LTE condition) I read the AR4 section on atmospheric water vapor; it states that RH is UNCHANGED!
Arthur really needs to read the Chilingar paper on atmospheric convection; and the Robitaille paper on Stewart's Law; the issue is not equilibrium between the Earth and the rest of the universe, as Gore infamously opined, but equilibrium within the Earth/atmosphere climate system; this internal equilibrium is measured by, as Arthur's paper states, the commutative relationship between Tafe and Teff; these 2 parameters define the enclosure and nature of the object, Earth; once solar SW enters the atmosphere it is subject to Tafe and Teff; Stewart's Law and Kirchhoff are essentially equivalent because there is no universality applicable; absorbance must therefore equal emission; internal variations in the dynamic indices of the internal climate of the Earth are subject to dynamic adjustment via Miskolczian mechanisms, and the optical depth is maintained, as has been verified.
Anna V, you should research more on the internal heat "build up" as quite the reverse has been happening. Over geological time the Earth has been slowly cooling and plate tectonics has been slowing. If anything the internal heat will over time reduce and has been since the Earth formed. And in geological terms you would expect, over time, a depletion of carbon from the Biosphere, resulting in cooling. The only compensation for this is the increasing heat from the Sun, which will eventually cook the Earth. The increased heat flow from volcanic and mantle activity may help explain high temperatures in the distant past (and may have helped bring the Earth out of the Snowball Earth) but certainly they can't be used to explain current temps. The flux is too low (~0.1 W/m^2 ??)
jan, Seems everyone has started noticing how loose you are with your terminology. It would seem to be something you shoudl address. Also not that you have been repeatedly told that you can't apply Kirchoff's Law iin an Earth-like situation.
They have been considered. Look at the effect it has on permafrost.
Cohenite. You're still clinging to the convection idea and to Misko. How quaint.
You can't apply Kirchoff's Law here. The grey-body assumption doesn't hold true.
"this internal equilibrium is measured by, as Arthur's paper states, the commutative relationship between Tafe and Teff"
This doesn't make sense…
Nor does this…
"once solar SW enters the atmosphere it is subject to Tafe and Teff;"
It sounds all sciency but it is rubbish.
"internal variations in the dynamic indices of the internal climate of the Earth are subject to dynamic adjustment via Miskolczian mechanisms, and the optical depth is maintained, as has been verified."
And this doesn't particularly mean anything. If there were such good climate controls we would not see the variations we see in paleoclimates.
internal variations in the dynamic indices of the internal climate of the Earth are subject to dynamic adjustment via Miskolczian mechanisms,
What he seems to be saying is that his 'mechanisms' can make clouds. A bit too Deus ex Machina for me, as someone else has noted.
What does it, or what is it supposed to, mean?
" but certainly they can't be used to explain current temps. The flux is too low (~0.1 W/m^2 ??)"
Just what I said, bulk turned into surface like epicycles.
There is another similar contribution from tides ( the moon will finally fall in the earth, that should heat up things).
I am not saying that the earth has not cooled from geological times. I am saying that within our "long intervals" ( 30 years, 60 years), this extra energy should be kept into the energy balance, which it is not now.
And nobody accounts for the thousands of ocean bottom volcanoes either in the energy balance or in the CO2, simply because they do not know.
Nathan: "jan, Seems everyone has started noticing how loose you are with your terminology. It would seem to be something you shoudl address. Also not that you have been repeatedly told that you can't apply Kirchoff's Law iin an Earth-like situation."
How so it's irrelevant what the body is if thermal energy in = thermal energy out it's in thermal equilibrium. The reality is that any for instantaneous measure it isn't e.g like the solar constant varies over about 90 watt/m^2 over the course of a year. If you average it over the year or two years or any complete period you have no change it's a constant. The nett energy content is also the same or the cahnge is zero but it is a red herring to the issue as to whether it's physically correct to allow for clouds obstructing incoming and having them miraculously disappear for outgoing.
Anna v, those "long periods" are just annual cycles and over that time geothermal activity is too insignificant to take into account.
It's not my rubbish; you can't have AGW unless you have a base state or equilibrium; Arthur knows this;
"If it doesn't average to zero for a long period of time, the energy of the planet would cumulatively build or decline."
Equilibrium: def; "a body on which forces are acting can be in equilibruim only if the resultant force is zero."
Say it aloud lads; AGW needs zero; ZERO; AGW is based on zero. Anyway, what are you still doing here NT; you've had more farewells than Dame Nellie? I thought you had some stiff diagrams to work on?
I think you haven't looked at this at all. Arthur did mention the internal heat flux. The flux of energy from undersea volcanoes is simply too low to be important.
And rather than claiming "they don't know" perhaps you should write "I don't know" as there have been many estimates of heat flow from volcanic activity.
Also if the heat flow has been over thousands of years more or less constant, why have we seen a rise in temps now?
Cohenite, what sort of equilibrium does AGW depend on? Thermal? Radiative? Mechanical? You don't know what you are talking about.
Arthur said this "This is a steady state situation, it is not thermal equilibrium. Kirchhoff's law in its simplest form does not apply."
I note that you didn't actually try and explain what you meant… Probably because you don't know. It was an exercise in postmodernism yes?
Oh yeah, I can't keep away… Oh well.
You'll be happy to know I finished them.
Jan, I gave you a link to the Grey-Body Assumption. I can do no more… Maybe you can Google it? I don't know. It has to do with the difference in wavelength between emiited and absorbed radiation. Kirchoff's Law doesn't apply.
How so it's irrelevant what the body is if thermal energy in = thermal energy out it's in thermal equilibrium.
Because that's not the definition of Thermal Equilibrium.
Nathan: "Arthur said this "This is a steady state situation, it is not thermal equilibrium. Kirchhoff's law in its simplest form does not apply.""
Yes he's playing words in order to redefine "equilibrium". Perhaps he just doesn't know what it means.
The description he gives and the method he uses implies equilibrium not a merely a steady state. The real earth might well be in a steady stated but that would make the deal far more complicated than it is for his equilibrium model.
This inconsistency is based on a false notion that there is cloud obstruction for incoming radiation and no obstruction for outgoing radaition. This is simply untrue.
Nathan: "Jan, I gave you a link to the Grey-Body Assumption."
You could try to understand it and what he meant by more accurate integral equations. If you integrate of the spectrum of incoming radiation and over the (different) spectrum of the outgoing you must get the same total radiation in both directions. The idiotic assumption made is that incoming radiation is due to grey body out going is due to black body rather than coloured the coloured version will give the same temperature as the grey body assumption not as the black body assumption.
SJT: "Because that's not the definition of Thermal Equilibrium."
You have a better one? Then lets have it and be careful to show us how it's different from the various different but consistent versions I've given.
http://www.splung.com/content/sid/6/page/thermalequilibrium
A body is in thermal equilibrium when there is no energy transfer between the body and its surroundings.
There is clearly an energy transfer. Arthur quite clearly stated, "no transfer" means just that. It's not good enough to say, "no net transfer".
There also seems to be some confusion about Kirchoff's law.
AFAIK, you are assuming it works in terms of fluxes, but it doesn't. It applies in terms of emissivity/absorption.
According to your logic, the earth could never be made to get warmer or cool. Any increase in incoming radiation from the sun would instantly be matched by increased radiation from the earth. No warming.
I don't know where anna v is coming from-
"We have been forced ( pun intended) to be looking at energy balances as surface effects: Watts per meter squared. Nevertheless, the earth is a three dimensional volume, with heat capacities , on the one hand, inherent volcanic heat ( the temperature goes up the lower one digs in the mantle, and even at shallow basements it is around 14C, very close to the "average temperature"), and gravitational tides that also input bulk energy. The oceans are cold, but they also are heated from the volcanic activity and the higher mantle temperatures"
but its more sloppy arguments and precious little physics being deployed
"The oceans are cold" however they are not all ice yet. In fact many creatures including mammals can live in them and have done so for ages.
Jan: I look forward to that paper beginning with all your definitions. However when it comes to using a few empirical values in your math, I suggest you don't start with recent work from blogs as there needs to be a consensus on a range of variables in your framework for the thing to fly.
Consider too the possibility of Gaia in any feedback mechanism. Imo that's more likely than anna's gurgles from the deep
Gaia is interesting. The idea features quite stringly throughout paleo-reconstructions of ecosystems.
Jan will mock you for it, though. As will others. Gaia has a bad rap as some sort of spiritual thing.
Nobody is confusing flux with a and e; the irony of this thermal equilibrium business is that both the AGW atmospheric model of semi-infiniteness and the semi-transparent model of M rely on it; for M, Aa=Ed, where Aa is the absorbance of the surface IR up Su; Ed is the IR emission from the atmosphere down Ed; for M's model both Aa=Ed and Su=Ed; for the AGW model neither does; however for the AGW model each succeeding layer of opaque atmosphere must equal the one beneath it; at that stage of thermal equilibrium IR from the surface will pass to the next layer; the surface will continue to heat because of the isotropic effect with each layer continuing to send LDR to the surface; the optical density and the tropopause will continue to expand and theoretically there is no limit, if CO2 continues to be added to the atmosphere, to the heat build-up at the surface which has a thermal discontiunuity with the atmosphere at all levels. There is no such layering in M's model; the optical depth is set and when Aa=Ed then Su=Ed; the thermal equilibrium ensures there is a radiative balance between the surface and the atmosphere; the thermal equilibrium is maintained by atmospheric water levels adjusting to internal changes like extra CO2. Off course, with external changes like increased TSI and insolation the equilibriums would be changed.
at that stage of thermal equilibrium IR from the surface will pass to the next layer; the surface will continue to heat because of the isotropic effect with each layer continuing to send LDR to the surface; the optical density and the tropopause will continue to expand and theoretically there is no limit, if CO2 continues to be added to the atmosphere, to the heat build-up at the surface which has a thermal discontiunuity with the atmosphere at all levels.
Of course there's a limit, the TOA. It all gets there in the end, it's just a matter of how long the journey is. The more pressure broadening, the higher the concentration, it just makes the journey a little longer, that's all. But it's enough.
"the thermal equilibrium is maintained by atmospheric water levels adjusting to internal changes like extra CO2. Off course, with external changes like increased TSI and insolation the equilibriums would be changed."
Your claiming clouds know whether to form, depending on if it's the sun or CO2 forcing the climate? Smart clouds.
Will; you're missing the point; 'semi-infinite'; there is no limit if CO2 keeps increasing; the Kirchhoff equilibrium keeps rising; I suppose it would stop when the TOA merged with the sun.
Will; clouds, like the rest of nature, don't give a rats; humanity has adjusted to conditions on Earth, not the other way round; and Gaia is a hippie's fantasy.
"Will; you're missing the point; 'semi-infinite'; there is no limit if CO2 keeps increasing; the Kirchhoff equilibrium keeps rising; I suppose it would stop when the TOA merged with the sun."
Kirchoff applies to the emission/absorption, not the flux. The CO2 effect, as has been widely reported here, is logarithmic. There are positive feedbacks, but they have their physical limits, too. If you want to propose enough CO2 to reach the sun, I don't think there is enough.
Will, will you please buzz off and let me have the last comment.
I'm hoping Arthur comes back.
Anyway, back to Miscolszci.
I like this comment on ER.
I think Miskolczi's paper could have been written in two sentences:
"The greenhouse gas theory that has been used for the last century is TOTALLY WRONG! The proof is left as an exercise for the reader."
Since even his supporters have to keep asking him what he means, it hit's the nail on the head.
His invocation of K's Law isn't saying that up and down radiation is equal. The balance at the surface is expressed in his Eq 2. What he is equating is down radiation E_D and an absorbance A. Why I say that this isn't Kirchhoff is that, in any statement of K that I have seen, emissivity is equal to absorptivity. These are coefficients, properties of objects. A body has much the same emissivity regardless of how much it IR is emitting. But no, M equates an actual emittance E_D with an actual absorption A, which I think is quite wrong. He then says "The physical interpretations of these two equations may fundamentally change the general concept of greenhouse theories."
McIntyre is much smarter than you guys at playing the game. Don't actually make any claims, just attack the other guys, and don't attack the basic science, that's just dumb. Only go for the more esoteric stuff that's on the bleeding edge.
Supporting someone like Miscolski just opens you up for ridicule.
Also from Eli, a link to.
According to Arthur Smith, this isn't established. Or more specifically, since SU/2 = SU(A-GN) is trivially the same thing, these aren't different equations, since A=1 and G<.5 means that this is:
SU*.5 = SU/2 * (1-.5)
.5 = .5
Without showing that there's any cause relationship between the two. The relationship doesn't have to hold, my friend explains, because he's simply multiplying both sides of an equation by constants and numbers that he's arbitrarily asserted.
Gavin: "Consider too the possibility of Gaia in any feedback mechanism."
While I like some aspects of the Gaia theory it's not really relevant here.
http://landshape.org/enm/models-of-greenhouse-effect/
Miscolzci is trashed, but some people seem to be oblivious to the fact.
SJT: "Kirchoff applies to the emission/absorption, not the flux"
Absorption and emission is the flux.
This is even sillier than the one above. Everything with T>0 emits thermal radiation so transfer does not stop unless an object is at 0 K so the only way to have no transfer is to have no net transfer.
My bad, emissivity/absorbivity. That's what you get for talking to someone who isn't a scientist.
Everything with T>0 emits thermal radiation so transfer does not stop unless an object is at 0 K so the only way to have no transfer is to have no net transfer.
No, he is talking about thermal equilibrium. (Once again, IANAS).
At that point,everything out, equals everything in. The earth does not meet that condition.
Thermodynamics deals with equilibrium states. The word equilibrium implies a state of balance. In an equilibrium state, there are no unbalanced potentials (or driving forces) with the system. A system that is in equilibrium experiences no changes when it is isolated from its surroundings.
Isolate the earth from it's surroundings, there's going to be a lot of changes.
Mr Niche has been doing a good job of trashing Miskcolczi, even if he doesn't seem to be aware of the fact.
http://landshape.org/enm/kirchhoff-law-miskolczi-part-3/
Aa=Ed
1=1, as someone pointed out on a blog somewhere. He has defined Aa to be equal to Ed. But the the LW radiation that is absorbed in the atmosphere also heats the atmosphere. Aa != Ed.
Comment from gavin
"The oceans are cold" however they are not all ice yet. In fact many creatures including mammals can live in them and have done so for ages. "
And your point is just a snide remark?
My point is that there is a lot in the earth physics that has not been taken into account. I continually see new volcanoes in the ocean references, and nobody seems to care.
Yes, the geologic and tidal energies are maybe a few percent of the epicycle energies of Watts/m2 from the sun, but I should not have to remind you that the anthropogenic CO2 that is supposed to be so catastrophic is about a few percent of the natural CO2 which is in total 3% of the green house gases, or something similar.
If a bit of gas in parts per million in the atmosphere is important enough to study, higher percentages of input energy should not be ignored, in my opinion, just because nobody has the desire to measure in situ what is happening.
I have tried to read the volcano links, but they are on a different page, not an AGW page. It needs a graduate student to compile and make sense of which are active volcanoes and how much, which regions have been studied and which are unknown, which are the thermal regions and which emmitt CO2.
SJT" "Aa=Ed
Not really it's empirical data not something he pulled out of the air.
Your other piece of stupidity:
"At that point,everything out, equals everything in. The earth does not meet that condition"
With earth swimming around in a vacuum everything in is radiant heat absorption and everything out is also radiant heat absorption.
Earth does meet that criterion there are no other significant sources and sinks.
Google "Grey Body Assumption"
Look for links that relate to thermodynamics, they will probably be books.
You will see that Kirchoff's Law doesn't apply when the absorbed radiation is of a very different wavelength to the emitted. They usually give the Earth as an example.
Nathan: "You will see that Kirchoff's Law doesn't apply when the absorbed radiation is of a very different wavelength to the emitted. "
What you would have found had you understood it that where the emitted wave length is different from the absorbed (fluorescence) Kirchoff's law doesn't hold for each emission or absorption line but it does hold when integrate over the absorbed and emitted spectra. You will never get the total thermal absorption != total thermal emission for a body in thermal equilibrium. i.e. Kirchoff's law holds.
NT; since you and your sidekick, Will, scorn any contrary viewpoint, and have been pushing what you believe is Smith's proof of the non-applicability of Kirchhoff and equilibrium, and how ridiculous M's theory is for incorporating Kirchhoff, and so on and so forth, I thought I would get a source who you and Will both revere to establish that Kirchhoff and equilibruim is valid;
http:rabett.blogspot.com/2008/06/once-more-since-world-no-longer-needs.html (// excluded)
Hi cohenite: His point 8 is the holy grail of thermodynamics the perpetuum mobile.
This means that there will also be increased radiation in regions of the spectrum where greenhouse gases absorb which, in turn, will warm the atmosphere but cannot escape to space. Radiation absorbed in the atmosphere and scattered back to the surface, warming the surface yet further.
It seems a little confused so we can't really be sure what he is saying so expanding a little.
Absorbed radiation is not scattered back it is re-emitted.
Scattering does no (or very little) work so it can warm a little actual reflection does more you get all that from clouds. These processes are similar to those that cause cloud albedo but work to inhibit emission. This is what Smith ignores in his paper.
You don't get back scattering from CO2 there you get absorption and thermalising of the energy by increasing the mean kinetic energy of the whole ensemble of atmospheric particles this is work done by heat moving from a warm reservoir on the surface to the colder atmospheric reservoir. This energy is not longer available to to the work of warming the the hot reservoir it came from even more it can however do the work or warming the cooler atmosphere above it.
Jan; on another issue; David gave me the heads up about optical depth; as I understand it the OD for M's model is much less than the optical depth for the semi-infinite model; which means much less of a greenhouse effect; but as well it means that when there is an increase in external energy there will be less of a climate response; the semi-infinite model not only would have a much more pronounced effect due to the larger OD, but would also have a runnaway due to the layering effect which has the result of taking the photosphere where the OD=1 (which corresponds to Kirchhoff) higher and higher into the atmosphere; do you agree with this and, as a corrollary, that M's model can explain hotter or colder periods in Earth's climate?
Cohenite, crikey moses norah!
"In the atmosphere below 100 km there is always a local effective temperature, thus the absorbtivity of the GHGs equals its emissivity (Kirchhoff's law)"
You do realise that what he is saying, is exactly what I have been saying.
If the absorption and emission spectra are of a similar wavelength Kirchoffs Law holds, so here the emission and absorption spectra are both in the IR range and don't very much. He is specifically talking about absorption and re-emission by GHG's (and below 100km). BUT it doesn't apply when the incoming radiation is of a substantially different wavelength.
"Smith's proof of the non-applicability of Kirchhoff and equilibrium, "
No, I linked to numerous text books and websites. The Wiki pages also confirm the non-applicability.
This all stems from Jan assertion that when you calculate Teff for the 235 w/m^2 you need to divide it by 0.7. However, because Kirchoff's Law doesn't hold, and because the Earth's emissivity is dependent on wavelength we find that the Earth's emissivity is around 0.98, so when you do the calcs you get a Teff of 255, rather than the Teff of 279 that Jan gets.
This is not my theory. it's not something specific to Arthur Smith either. This has been around for a long time. It has just been disputed by Misko, and Misko does look rather flawed…
The semi-infinite models actually UNDERESTIMATE the paleocllimate of the Earth. They cannot actually get it hot enough for the Hot house times in the Earth's Past (i.e. most of the Phanerozoic). they need to find other ways to heat the Earth, typically using more SH, or other GHG's.
hi cohenite
I missed this when David posted it earlier but caught it this time when he linked again yesterday.
http://landshape.org/enm/wp-content/uploads/2008/06/AIGnewsSC.pdf
have a look at it if you haven't already I'm a bit busy at the moment I'll get back to you. Keep in mind though that the semi-infinite models has an opaque atmosphere (infinite optical depth) at the surface and zero OD at top which is OK for suns but not earth like planetary atmospheres.
Eli is not stating Kirchoff (emissivity/absorptivity not emission/absorption.)
My post before on the radiative balance already covered this idea. Emission almost equals absorption, these are the only means for energy to arrive and leave, but there is a slight imbalance. That is what causes warming or cooling.
Eli is also not stating there is a Thermodynamic Equilibrium, but, as AS as stated, a "Steady State".
Yeah, like my 'trapdoor' analogy.
It's transparent to the incoming short wave radiation but opaque to the outgoing long wave radiation. (Approximately).
The LWR does get out, eventually, it's just a matter how many hops it takes to get out. The more GHG in the way, the longer it takes, the warmer it gets.
That's not breaking any laws of thermodynamics, any more than a blanket is.
Nathan: "That's not breaking any laws of thermodynamics, any more than a blanket is."
It's those idiots who think a blanket is positive feedback that are violating the laws of thermodynamics.
So NT; what eli says is what you have been saying all along? My comment at Oct 21, 5.09pm: Kirchhoff applies within the atmosphere, universality is not an issue and Kirchhoff is equivalent with Stewart's Law.
Nt at 5.21pm Oct 21; "You can't apply Kirchhoff's Law here."!?
As I say the semi-infinite AGW model uses Kirchhoff to prolong the emission; M's semi-transparent uses it to show the greenhouse delay is negligible.
Cohenite, I have always said that you cannot apply Kirchoffs law when the absorped radiation is of a substantially different wavelength to the emitted.
Read it again. Eli is saying that GHG's obey Kirchoff's Law (becuase they absorb and emit with similar wavelengths). But you can't use it in the Earth-Sun-Space systems because the Sun's radiation is a very different wavelength to the Earth's emitted radiation.
I don't know if you are being deliberately stupid or if you just refuse to think it through.
Kirchoff's Law relies on an assumption (that works for most engineering situations) that the absorbed and emitted radiation are of a similar wavelength (eg GHG's absorbing and emitting IR radiation). When they are of different wavelengths the assumption fails and the Emis=Absorp of Kirchoff's Law no longer holds (eg Earth absorbing Sunlight (UV and visible light) and the Earth emitting IR).
I see know what you wrote. I thought you were talking about the Earth-sun system (which is what Jan is typically talking about).
So does that mean that you accept Teff is 255? That's what you get if you accept Kichoff only for the atmospher.
I note you didn't adress any of my other issues I had with the statement you made… Have you decided what this:
"this internal equilibrium is measured by, as Arthur's paper states, the commutative relationship between Tafe and Teff;"
means yet?
Let's define Tave and Teff; is Tave the GMST; ~288K; is Teff the average of SB over the globe; you say 255K; the difference between the 2, 33K, you say is the measure of GH; what is the basis of commutivity between Tafe and Teff?