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A Note on the Stefan-Boltzmann Equation

According to American climatologist, Judith Curry, there are plenty of things to be skeptical about when it comes to Anthropogenic Global Warming, but the basic physics of gaseous infrared radiative transfer is not one of them.

Dr Curry, is the chair of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology and the co-author of ‘Thermodynamics of Atmospheres and Oceans’ (1999), and was speaking out against claims in a book ‘Slaying the Sky Dragon: Death of the Greenhouse Gas Theory’. 

There has been some discussion of radiative transfer theory at this blog mostly via notes I have posted from Alan Siddons, Holden, Massachusetts, who is a chapter author in the book and is very skeptical about the basic physics of radiative transfer as applied by mainstream climate scientists and in the IPCC reports.  

I was recently alerted to a blog post Dr Curry has started, ostensibly to discuss this physics and its application to global warming theory.   It seems to have stirred up interest again in this issue. 

An occasional commentator at this blog, known as Cementafriend, is also skeptical, in particular about how the Stefan-Boltzmann equation is applied by the climate scientists. 
Following is a note from Cementafriend to resurrect the issue here:

Is the Stefan-Boltzmann Equation used correctly

D Kern in the text book “Process Heat Transfer” states “Radiant energy is believed to originate within molecules of the radiating body, atoms of such molecules vibrating in simple harmonic motion as linear oscillators. The emission of radiant energy is believed to represent a decrease in the amplitudes of the vibrations within the molecules, while an absorption of energy represents an increase.”

But from where does the Stefan-Boltzmann equation come?

It appears that Josef Stefan determined around 1879 from experimental results that the radiative flux (W/m2) was proportional to the fourth power of the absolute temperature. His student Ludwig Boltzmann around 1884 derived a confirming equation and proportionality constant from statistical thermodynamics. This became known as the Stefan-Boltzman law.
Most laws have some boundary conditions i.e. they do not apply universally. Einstein demonstrated that with his theory of relativity.

It was quickly found that the Stefan-Boltzmann law/equation only applies to black bodies.
There is a question mark about the constant as it seems that it was derived from a flat surface inside a hemisphere. That is OK when considering heat transfer been two surfaces but may be inaccurate when considering a radiating sphere.

A different derivation of the Stefan-Boltzmann equation is give by Miles Mathis who the radiant heat flux to electromagnetic fields. This is interesting as one of the criticisms of Boltzman’s work is that he did not consider gravity in his thermodynamics but this is outside the scope of this short note.

Boltzmann proposed a distribution of energy flux which was later developed by Max Planck into Planck’s Law. The Stefan-Boltzmann equation can be derived from Planck’s law with some assumptions. (It seems that Boltzmann has a lot to answer for –one of his students was Arrhenius)

Engineers work differently to scientists. They have to consider best practice, what actually works to give a solution to a problem. They have to take account of boundary conditions and assumptions, which have been applied to give a workable solution for similar problems.
The first modification to the Stefan-Boltzmann equation is to apply an emissivity factor because a black body is a theoretical consideration which does not apply in reality.

The emissivity is the ratio of the actual power to the power of a black body integrated over the whole flux density Planck distribution at a particular temperature.

Engineering researchers have determined the emissivities for many substances over a range of temperatures. Some emissivities are shown in figure 5-12 and table 5-6 of Perry’s Chemical Engineering Handbook (Perry’s CEH). It will be noted that the emissivity varies with temperature. For some materials the emissivity decreases with temperature and for others it increases with temperature.

Perry’s CEH states “According to Kirchhoff’s law, the emissivity and absorptivity of a surface in its surroundings at its own temperature are the same for both monochromatic and total radiation.” However, the emissivity and absorptivity needs to be considered in relation to the temperatures of the source and receiver.

For gases, researchers have determined a wavelength spectrum of emission/absorption.
It can be found that pure 100% CO2, at one atmosphere pressure, absorbs energy in only narrow wavelengths. At 4.2 micron there is approximately 100% absorption over less than 0.1 micron range and in the wavelengths range 14.5 to 15.5 micron there is approximately 60% absorption. Now the sun has less than 1% of its total spectrum in wavelengths greater than 3.9 micron and less than 0.1% greater than 9 micron so the absorptivity/emissivity of CO2 for incoming radiation from the very high temperature sun is practically zero. A black body at 288K has about 0.1% of its spectrum at wavelengths less than 3.9 micron and roughly 8% in the range 14.5 to 15.5 micron, giving an absorptivity/emissivity of radiation from such a body for CO2 of less than 0.05.

While the change in absorptivity in the case of CO2 is small, it will be recognised that the emissivity/absorptivity is temperature dependent.

So far only a single remote radiating source has been considered. From engineering measurements it was found that the temperature of the receiver affected the amount of energy transferred. In other words there was a net heat transfer which requires modification of the Stefan-Boltzmann equation.

Some may call this back radiation. Engineers normally do not care about the detailed mechanism while the equations can give a useful result. However, the concept of back radiation would be in conflict with the second law of thermodynamics. Infra-red radiation is part of the continuum of electromagnetic waves. It is possible that a reduced series of waves set out only in one direction or that incoming and outgoing waves cancel. Professor Claes Johnson, an author of ‘Slaying the Sky Dragon’ gives a plausible explanation with the concept of threshold energy levels.

In heat exchangers the area of surfaces are usually not equal and they may not be parallel.
From measurements and geometry calculations Engineers have introduced View factors.
This is outside the scope of this short note. However, view factors must be a consideration in the Urban Heat Island (UHI) effect. The heat loss/gain of a bitumen road in a open rural area will be different from the surrounding due to different emissivity but it will also be different to a road in a city where there are adjacent buildings of various heights due to view factor corrections. Anyone saying UHI does not exist is either not telling the truth or has no understanding of heat transfer.

A gas is not a surface and requires a different treatment to determine heat transfer. Engineering researchers have over many years made measurements on combustion products in heat exchangers and furnaces. Hoyt Hottel, Professor of Chemical Engineering MIT in the late 1950’s developed an equation which allows the absorptivity/emissivity of a combustion gas to be calculated from the partial pressures of CO2 and H2O vapour, the beam length, the total pressure and individual emissivity factors from the black body radiation curves. The equation is given in Perry’s CEH as 5-145 and an example 6 “Calculation of Gas Emissivity and Absorptivity”. Text books such as Process Heat Transfer by D Kern have graphs which allow quick selection for temperatures down to 100F (310K).

There are computer programs now to ease calculations (but one must understand what the program achieves and its limitations). My calculations making assumptions such as 8km beam length, average pressure 62kPa, average temperature 262K, surface temperature 320K and CO2 partial pressure 2.4 Pa show the absorptivity of CO2 insignificant (less than 0.01). For water vapour in a clear sky (ie no clouds) I calculated an absorptivity of about 0.4. Clouds have varying emissivities and need separate determination.

In climate discussions the term albedo seems to be frequently used. This is just (1-emissivity). To me as an engineer the term albedo is gobbledegook and shows to a large extent the users do not understand heat transfer.

Beside the modification of the Stefan-Boltzmann equation to fit reality there are other complications. Heat transfer by radiation is really only applicable to a vacuum. Calculations, using appropriate emissivity/absorptivity factors and view factors, work when there is a large temperature difference because the heat transfer relates to the difference of the fourth power of temperatures. However, calculations have large errors because the emissivity is not well known and temperatures may be incorrect especially if measured by instruments which assume black body radiation. For example the sun is not a perfect black body. Measurements have found surface temperature spikes. No one truly knows the surface temperature at any point in time. Similarly no one knows the exact diameter. Calculations of insolation at some point of the earth’s atmosphere need lots of assumptions and there is no way it can be reported to two decimal places.

If there is a fluid between surfaces or above a surface convective heat transfer (natural and forced) and phase change (evaporation & condensation) can be more important with small temperature differences (less than 50K) than radiation. Such heat transfer will change surface temperatures over time. Conduction below surfaces may then become a controlling factor. This needs elaboration at some other time.

In summary there is nothing settled about the Stefan-Boltzmann equation. It cannot be used on its own to determine atmospheric temperatures.

by ‘Cementafriend’.

 *********
Judith Curry’s blog
http://judithcurry.com/2011/01/31/slaying-a-greenhouse-dragon/

Alan Siddons
http://jennifermarohasy.com/blog/2009/04/on-the-first-principles-of-heat-transfer-a-note-from-alan-siddons/

Miles Mathis
http://milesmathis.com/stefan.html

The book
http://www.amazon.com/Slaying-Sky-Dragon-Greenhouse-ebook/dp/B004DNWJN6/ref=sr_1_1?ie=UTF8&m=A7B2F8DUJ88VZ&s=digital-text&qid=1290760790&sr=1-1

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84 Responses to “A Note on the Stefan-Boltzmann Equation”

Pages: « 1 [2] Show All

  1. Comment from: cohenite


    Professor Pierrehumbert, please comment.

  2. Comment from: DavidK


    So, Cohenite really thinks he’s watching this blog, and his comments.
    If Cohenite really wants to question a real scientist, challenge him even, he would.
    He knows how to contact him, but he won’t.

  3. Comment from: ScienceofDoom


    I notice that some people think that Gerlich & Tscheuschner plus Claes Johnson plus Miskolczi adds up to an attack on the inappropriately-named “greenhouse” theory.

    Well- Miskolczi believes in the “greenhouse” theory, but believes that, for complex reasons, water vapor acts as a strong negative feedback.

    Gerlich and Tscheuschner believe that the “greenhouse” theory is a violation of the 2nd law of thermodynamics. They apparently, in their clarification, accept that “back radiation” exists, and that it “reaches the ground”, but don’t feel obliged to explain what happens to it after that. All part of their entertaining approach to physics.

    Claes Johnson doesn’t believe that quantum mechanics is correct. He doesn’t believe that such a thing as “back radiation” exists. (Because EM radiation is only waves and therefore the ground and the atmosphere form something like a resonant system).

    If you accept Claes you write off 100 years of physics including statistical thermodynamics and Gerlich & Tscheuschner and Miskolczi.

    If you accept Gerlich and Tscheuschner you write off Claes Johnson and Miskolczi.

    And if you accept Miskolczi you write off Gerlich & Tscheuschner and Claes Johnson.

    Of three contradictory theories, only a maximum of 1 can be correct.

  4. Comment from: DavidK


    Cementhead: Have you been able to get a response to your article posted here?
    Have you challenged his paper?
    Would like to hear back.

  5. Comment from: DavidK


    Sorry ScienceofDoom (whacky moniker)
    Science doesn’t work like that.

  6. Comment from: ScienceofDoom


    Many people have very confused ideas about thermodynamics and heat transfer basics.

    Much of what people criticize about “climate science” is actually a claim that fundamental radiant heat transfer theory is flawed. This article is no different.

    Books with racy titles like Fundamentals of Heat and Mass Transfer that contain nothing of climate science and have been in print for 30 years through many editions, endorse these basics.
    In fact, surveying all the books in a university library you find that the basics are identical and unquestioned in each. These books are used as a staple of undergraduate courses in heat transfer.

    A few comments:

    But from where does the Stefan-Boltzmann equation come?

    It appears that Josef Stefan determined around 1879 from experimental results that the radiative flux (W/m2) was proportional to the fourth power of the absolute temperature. His student Ludwig Boltzmann around 1884 derived a confirming equation and proportionality constant from statistical thermodynamics. This became known as the Stefan-Boltzman law.
    Most laws have some boundary conditions i.e. they do not apply universally. Einstein demonstrated that with his theory of relativity.

    It was quickly found that the Stefan-Boltzmann law/equation only applies to black bodies.
    There is a question mark about the constant as it seems that it was derived from a flat surface inside a hemisphere. That is OK when considering heat transfer been two surfaces but may be inaccurate when considering a radiating sphere.

    The Planck equation describes the spectral intensity (Watts per m^2 per solid angle (steradian) per um) for any temperature of a “blackbody”. A blackbody is simply the best emitter of thermal radiation – the “gold standard” if you will. Nothing can emit more than a blackbody but some come very close.

    If you integrate the Planck equation emitted from a planar surface over all wavelengths and all solid angles you get the Stefan-Boltzmann equation. It is simple geometry.

    More about this subject at Planck, Stefan-Boltzmann, Kirchhoff and LTE.

    The Stefan-Boltzmann equation is actually defined like this:

    E = εσT^4

    where ε is the emissivity, a value ranging from 0 to 1.

    So the Stefan-Boltzmann equation is not an equation that only applies to black bodies at all. It is well-used in heat transfer for any type of material. It is simply a matter of determining the emissivity for the material in question. This is usually done by measurement.

    What about spheres? If you take the irradiation (incident radiation) received from within a sphere the total value is a increased by a factor of 4, again due to geometrical considerations. Not much practical use, but you find it in more turgid atmospheric physics textbooks.

    What about the particular case of the transfer of radiation through the atmosphere?

    The equation of radiation transfer is known as Schwarzschild’s equation. This considers each wavelength in turn and is a well-proven equation, originally derived for stellar radiation. It isn’t the Stefan-Boltzmann equation and doesn’t use the Stefan-Boltzmann equation. It is based on fundamental physics.

    So apart from the last comment on Schwarzschild’s equation, this is basic stuff you find in any heat transfer textbook.

    And the equations of radiation transfer used to calculate the effects of different radiatively-active gases in the atmosphere don’t rely on the Stefan-Boltzmann equation.

    ..Heat transfer by radiation is really only applicable to a vacuum..

    This is not true. In fact, calculations of heat transfer by radiation in the atmosphere are very successful. See Theory and Experiment – Atmospheric Radiation. Calculating radiant heat transfer through a field with matter simply needs to use the right equations.

    ..However, calculations have large errors because the emissivity is not well known and temperatures may be incorrect especially if measured by instruments which assume black body radiation..

    So how do the theoretical spectra match the measured spectra – Theory and Experiment – Atmospheric Radiation ?

    Who says emissivity is not well known? See Emissivity of the Ocean as an example of some of the very thorough work done to calculate the emissivity of the ocean very accurately for satellite radiometers.

    ..In summary there is nothing settled about the Stefan-Boltzmann equation. It cannot be used on its own to determine atmospheric temperatures.

    In summary, all the heat transfer textbooks are very happy with the equation. It is extremely settled.

    And the calculations of radiative transfer in the atmosphere don’t actually use it.

    And yet another article with random assertions that doesn’t actually show anything wrong with current atmospheric physics.

  7. Comment from: ScienceofDoom


    Comment from: DavidK February 4th, 2011 at 6:09 pm

    who said:
    Sorry ScienceofDoom (whacky moniker)
    Science doesn’t work like that.

    “Sorry, doesn’t work like that.. QED. Case closed.”

    First you have to state your case, then you have to demonstrate why it’s correct.

    I don’t even know what your case is.

  8. Comment from: el gordo


    ‘First you have to state your case, then you have to demonstrate why it’s correct.’

    AGW is unfalsifiable (sic), because they keep moving the goal posts.

    http://blog.algore.com/2011/02/an_answer_for_bill.html

  9. Comment from: cohenite


    Hi SoD; I’ll stick with Miskolczi out of your 3 choices thanks; I am not aware of any peer-reviewed rebuttals of Miskolczi and G&T’s rebuttal is a fiasco by eli and his chums.

    In respect of Miskolczi some guy at another site put up this reference as rebutting Miskolczi:

    Rob van Dorland1 and Piers M. Forster2
    1 Royal Netherlands Meteorological Institute, De Bilt, The Netherlands
    2 School of Earth and Environment, University of Leeds, Leeds, UK
    Miskolczi (2010) theorizes that atmospheric CO2 increases cannot lead to an enhanced greenhouse effect and so can’t be a cause of global warming. We show his theory to be incorrect in its application of radiation theory and from direct atmospheric observations.

    But I can’t locate it and I know van Dorland is a Miskolczi hater from way back.

  10. Comment from: Louis Hissink


    Luke,

    “” I am not disagreeing with Louis” – oh pullease give it away ! (and of course you’d have to define which day as he chops and changes)”

    Oh really – I have always been consistent on this – and maintained the physical impossibility of a greenhouse gas effect which G & T demonstrated theoretically – so any variation on a daily basis you seem to observe would have to be attributed to your own changing perceptions, just as Lord Keynes did every time he was confronted with a contradictory fact – he changed his mind.

    What I don’t have a very high KPI score in, is the ability to interlocute idiots, sad to say.

    An idiot is someone who, on repeating the same action, expects a different answer. In your case it’s reading the same statement and getting different conclusions which you state above in my quote.

    And I notice not a peep out of you and your fellow travellers about the fact that if the Stefan-Boltzmann equation is to be applied to the earth, then it applies to the stratopause, the physical boundary between the earth and space, and not the rocky-liquid surface we stand and float on. But then I suppose as a graduate of post-normal science, such details are dismissed by you as another equal valid narrative.

  11. Comment from: Luke


    Louis – mate I have a long memory, as does Phil who sends hugs, and you’ve ducked and dodged on this for years. Interesting that an empirical sort of guy like you would go with theory too …. mmmm

    I wonder what all those net radiometers are measuring. What do you think Louis?

    Cohers – http://www.realclimate.org/docs/Rebuttal_Miskolczi_20100927.pdf

  12. Comment from: cohenite


    Thank you luke; is that peer reviewed?

    An initial impression: on page 2 they say:

    “As a next step using his quasi radiative equilibrium model, Miskolczi calculates the relationship between outgoing longwave radiation (OLR) and the infrared flux originating from the Earths surface (Su). The relationship is a function of infrared optical depth (τA) only”

    This is wrong; on page 17 of Miskolczi’s 2nd paper, figure 10:

    http://www.friendsofscience.org/assets/documents/E&E_21_4_2010_08-miskolczi.pdf

    Miskolczi measures changes in “the true greenhouse-gas optical thickness”. This is made up of two parts which are depicted in Figure 10. The first is τA which is defined as “the total IR flux optical depth” [page 5 Miskolczi 2007]. This is a measure of the total amount of infra-red or LW radiation which is absorbed between the surface and the TOA. The second is A which is the flux absorbance [page 3 Miskolczi 2010] and is a measure of what wavelengths of LW are being absorbed and transmitted in the atmosphere.

    The rest of the ‘paper’ merely restates the SH and OLR disputes.

  13. Comment from: ScienceofDoom


    Comment from: cohenite February 4th, 2011 at 8:17 pm

    Hi SoD; I’ll stick with Miskolczi out of your 3 choices thanks; I am not aware of any peer-reviewed rebuttals of Miskolczi and G&T’s rebuttal is a fiasco by eli and his chums.

    And so you have missed my point.

    If you stick with Miskolczi then you have accepted that G&T are wrong.

    If you think G&T are correct then you have accepted that Miskolczi is wrong.

    If you are happy with both then you haven’t begun to understand the subject.

  14. Comment from: cohenite


    I said I will stick with Miskolczi.

    And that doesn’t mean that eli’s rebuttal of G&T was any good, regardless of what you think of G&T. Personally I have great hopes for G&T; they are witty as their 2nd paper shows:

    http://arxiv.org/PS_cache/arxiv/pdf/1003/1003.1508v2.pdf

    They say: “We assume that, as usual, acceleration due to gravity is vertical”

    They are fun guys.

  15. Comment from: cementafriend


    @DavidK February 4th, 2011 at 7:03 am, I have not commented on Pierrehumbert previously. There was a discussion about his views (amongst other things) at http://judithcurry.com/2011/01/19/pierrehumbert-on-infrared-radiation-and-planetary-temperatures/ Only glanced at a few of the comments but the following caught my eye as being from someone who understands thermodynamics :-
    “No one has learned anything here, or from Pierrehumbert’s recapitulation of “The Radiative Transfer Theory,” in capitals to communicate its divine status. The theory ignores convection; it ignores the ideal gas law and the gravity that compresses the atmosphere, and increases the temperature, as a monotonic function (increase) of depth (Pierrehumbert makes the insane claim that “An atmospheric greenhouse gas enables a planet to radiate at a temperature lower than the ground’s” — NO, the thermodynamic lapse rate, depending only on gravitational g and the atmospheric specific heat does that); it ignores the Venus/Earth data that proves there is NO greenhouse/Tyndall effect whatsoever, on either planet. It assumes that anything with a temperature is a blackbody (absorptivity=emissivity), including the surface of the Earth (obscene misunderstanding of basic physics). Pierrehumbert assumes no scattering of IR radiation, because he does not even have an understanding that absorption and re-emission”

    Someone above commented on the emissivity factor- I suggest to look at the definition -the ratio of the actual absorption/emission to that which would occur with a black body. Maybe there are some, who want to confuse the situation, use another definition.

    This article mentions high sun surface temperature spikes http://physicsworld.com/cws/article/news/44717. Normal quoted temperatures assume the Planck flux distribution relation. The sun’s diameter is based on visible measurement from an arc angle of 31.6-32.7 minutes. Is that the true diameter? Irradience measurements assume the S-B black body equation. The article by Kopp and Lean http://www.leif.org/EOS/2010GL045777.pdf gives a figure of 1360.8+-0.5 W/m2. While the results shows variablity in past measurements how can anyone believe the precision? and what about the Corona? Can thoughts about electro-magnet forces be ignored?

  16. Comment from: ScienceofDoom


    for cohenite February 4th, 2011 at 9:42 pm:

    Oh they are witty, no doubt. They pitched it just right.

    Amazing how performing a few double integrals impresses the punters. I hear that they had a book running in Germany as to 1) how many blogs would endorse their work, and 2) how many government inquiries would cite their work.

    It was off the charts (no one won) so they decided to produce a few more papers.

    If they know anything of the last 5 decades of atmospheric physics they are keeping it to themselves. As described in On the Miseducation of the Uninformed by Gerlich and Tscheuschner (2009).

  17. Comment from: Louis Hissink


    Luke,

    “Louis – mate I have a long memory, as does Phil who sends hugs, and you’ve ducked and dodged on this for years. Interesting that an empirical sort of guy like you would go with theory too …. mmmm

    I wonder what all those net radiometers are measuring. What do you think Louis?”

    What are your blathering about? As for “net radiometers”, what, measuring nets in the atmosphere? More like measuring “Netwits”, no?

  18. Comment from: Luke


    Thanks Louis – as usual you have simply proved that you’re a total bullshit artist. Never answer a question – just hand wave – you’ll run away soon (as usual).

    http://en.wikipedia.org/wiki/Net_radiometer

  19. Comment from: Louis Hissink


    Thanks Luke,

    I note that the net radiometers you link to have downward facing sensors, measuring, ……what?

  20. Comment from: Louis Hissink


    In Addition there are vertical oriented sensors; Question? Why design parabolic collectors for the reflected signal compared to the primary one?

    Huh?

  21. Comment from: Louis Hissink


    Still here Lukey, waiting Smmmmkiss

  22. Comment from: Luke


    It’s a net radiometer – singular. (not radiometers)

    Which has components. two pyranometers and two pyrgeometers.

    Do you really have to ask what the downward sensors are measuring. reflected SW and emitted LW

    Most importantly what is the upward facing pyrgeometer measuring at night.

  23. Comment from: DavidK


    @ cementafriend February 4th, 2011 at 10:12 pm

    Thanks for replying. That person who caught your eye out of 675 comments was not you, was it?

    Think about it, there is no way “someone who understands thermodynamics” with a moniker like ‘cementhead’ would post on Judith Curry’s site. As a devil’s advocate, that ‘someone’ could have been you. Anyway, with so many comments, it’s hard to tell.

    Judith Curry herself is very impressed with Pierrehumbert’s paper, as are a number of other comenters, but she/they too could be wrong.

    You seem to know what your talking about cementhead, any chance of submitting a rebuttal paper to Physics Today, under your own name of course?

  24. Comment from: Louis Hissink


    Luke,

    the upward facing instruments measure downwelling IR – but I contend that the measured IR is not to be solely from radiating gases but from atmospheric electricity as well. As air is isotropic IR should, at night, be uniform laterally, strongest in the upward vector (heat loss to space) but as air density decreases with height, the downward IR should be lower. That it isn’t doesn’t mean there is a layer of radiating gas over head, a physical nonsense in a well mixed gas, but the presence of another IR producing physical phenomenon.

    It’s atmospheric electricity operating in plasma dark current mode.

    However, as your “science” rejects electricity having any role in geophysics, you then conclude that this downwelling IR has to be exclusively from radiating gases.

  25. Comment from: cementafriend


    @ DavidK February 5th, 2011 at 10:08 am
    I would not normally reply to persons who can not make reasoned comments. You could have looked through the Judith Curry’ post yourself. The person who made the critique about Pierrehumbert has a website here http://www.blogger.com/profile/03210275295826050501. You could have found that by clicking on his name. I know nothing about Harry Huffman but his comment about the lack of consideration of the lapse rate caught my eye as it is the same as my initial reaction. Maybe you could look at his website and contact him to find out more about his critique.

    If you would have digested my comment above you would find I have no objection about the article in Physics Today. I said that I found the article by Kopp and Lean (link supplied) interesting but I can not believe the quoted precision. In the paper it will be noted by you and others that the measurement in the most recent satellite is done in a vacuum to improve accuracy. However, think about the result if one assumes the emissivity of the sun is actually 0.99 (or even lower at times) instead of 1.00. The spectrum of the sun does not follow perfectly the black body Planck spectrum at any particular temperature. Is that due to measuring error, some incorrect assumptions, an error in the spectrum relation or something that we do not understand?

  26. Comment from: Luke


    Well we’ve progressed (seemingly as we never quite know with Louis) to the point where you agree that one can measure downward longwave radiation on clear nights. All over the world.

    As for what flux is strongest – well that’s up the physics and the net result of the incoming and outgoing longwave is the temperature you get.

    So you’ve raised an interesting hypothesis – let’s test it.

    (1) Do we have any evidence that this atmospheric electricity emits in the bands measured?

    (2) See Figs 1 and 2 here Upward and downward radiation measurements, EBEX 2000, Kohsiek (2007) http://scienceofdoom.com/2010/07/31/the-amazing-case-of-back-radiation-part-three/

    So note the long wave up and down and the diurnal pattern – so you have now introduced some presumably chaotic “atmospheric electricity operating in plasma dark current mode” hypothesis that could produce this radiation budget pattern. An additional source !!

    So in that case measurements (this site and day’s data is just one of many around the world) would look nothing like this. You’ve invented a whole new physics. And you have the temerity to lecture on “post-normal” science. Ye gods man!

    (3) and in this simple experiment on absorption – where does the energy go Louis?
    http://www.youtube.com/watch?v=SeYfl45X1wo

    (And I remind you that serious sceptics like Lindzen and Spencer don’t deny there is a greenhouse effect and that that is about 1C for 2 x CO2 – they dispute the role of water vapour feedbacks and clouds).

    So Louis – Bullshit !

  27. Comment from: cohenite


    L&C have a figure for feedback 2XCO2 CS of 0.7C; Spencer and Braswell, 0.6C

  28. Comment from: Louis Hissink


    Luke,

    1. I have never doubted the results from the measurement of downwelling IR. I have never denied the existence of this downwelling IR either, but I don’t think all of it comes from the supposed “greenhouse” gases.

    2. Third sentence – so temperature is the result of two IR vectors, upwelling from the earth, and downwelling from the atmosphere? Bit of a convoluted way of measuring temperature isn’t it? Given that a molecule of CO2 at sea-level is at a higher temperature of another molecule of CO2 100 meters above it, then there is a problem how that cooler molecule of CO2 can affect the thermal state of the hotter molecule, let alone raise the temperature of the hotter CO2 molecule; This is tantamount to asserting that an ice cube is capable of raising the temperature of the water its floating in.

    3. Does electricity emit radiation in the measured bands, ie IR. When passing through matter, ie. air, electric currents raise that medium’s thermal state, or temperature. Plenty of evidence for that.

    4. Your references in (2) are not of peer reviewed scientific literature, and using your own, well stated views, ignored.

    5. Who said that atmospheric electrical processes are chaotic? Not I. Strawman argument.

    5. Your Youtube video is nonsense – the reason the candle extinguished is because of the replacement of O2 by CO2, which caused the candle to stop burning. And another non sequitur you make, by the way.

    6. As for Lindzen and Spencer, I can’t comment, since none of us swap opinions on this apart from the imaginals you and your fellow traveling companions imagine.

  29. Comment from: Luke


    1. Oh yes you have !

    2.(a) really dumb – it definitely does – haven’t you heard of net radiation ! perhaps then you can explain http://rabett.blogspot.com/2008/09/light-dawns-there-are-styles-in-science.html or the humble IRC light bulb http://lightingpro.com.au/catalog/osram_irc_halogen_lamp.php or a radiation shield on a furnace. We’re talking radiation not conduction of heat !

    2 (b) so why does the passage of clouds affect Spencer’s night time temperature datalogger trace? http://www.drroyspencer.com/2010/08/help-back-radiation-has-invaded-my-backyard/ according to you this can’t happen – colder to warmer

    3. well let’s see the peer reviewed references on the measurements – no hand waving pls

    5. (a) so this is happening uniformly all the time is it – I hadn’t noticed – peer reviewed reference pls

    5. (b) don’t be so STUPID – the candle is outside the tube – for heavens sake man

    6. Utter crap – Spencer has made major blog posts on the topic

    So Louis single handly without any publications has dismantled 100s of scientists doing radiation budget analysis. Pullease ! What a weener.

  30. Comment from: DavidK


    Thanks cementalink, I will follow up. Obviously, more research is required.

  31. Comment from: Larry Fields


    The article mentioned radiative transfer theory. Sorry for being nonpolitical, but THE top person in the field is Mamikon Mnatsakanian, an Armenian-American mathematician and astrophysicist. Mamikon’s health is quite frail, and I hope that he lives to publish a book on radiative transfer theory.

    Mamikon”s website is considerably more accessible than one would expect. Here’s a link to a ‘psychic’ computer animation that he created.
    http://www.its.caltech.edu/~mamikon/AttractorCN.html
    Yes, it’s a trick. But it’s the most diabolical kind of trick; it’s done with logic.

  32. Comment from: Jennifer Marohasy » More on the Stefan-Boltzmann Equation: A Note from Martin Hertzberg


    [...] Part 1.  http://jennifermarohasy.com/blog/2011/02/a-note-on-the-stefan-boltzman-equation/ [...]

  33. Comment from: Mark Latham on Carbon Tax – Science, the fourth arm of government. « No Carbon Tax Website


    [...] expert ‘scientists’ are more believable. The non-scientists public may not know Stefan-Boltzmann Equations, but they are very good at detecting telltales of a culture of insiders, of [...]

  34. Comment from: Vincent Gray


    I continue to be amazed at the number of people who still accept the IPCC dogma that the earth is flat, static, in equilibrium. and exclusively controlled by radiative energy exchanges.
    I am also amazed by people who cannot accept that the Stefan Boltzmann equation is concerned only with the temperature of an emitter, and not by that of any receiver.of the radiation

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