John Nicol: Greenhouse Effect re-examined

Posted: October 25, 2010 by tallbloke in climate

Commenter ‘Paul’ on Dr Roy Spencer’s blog writes:

John Nicol, PhD, Professor Emeritus of Physics, James Cook University, Australia, states in his paper Climate Change (A Fundamental Analysis of the Greenhouse Effect),

The 22 pages of closely argued, mathematical and physical analysis of how energy is transmitted from the surface through the atmosphere, answers all questions and demonstrates that : –

1) Water vapour and clouds dominate the troposphere’s ability to absorb outgoing long-wave radiation, with the amount of water vapour decreasing with altitude. Most absorption occurs in the first few meters of atmosphere above the surface.

2) 99% of the absorbed photons are not re-emitted, due to collisions with other molecules and the consequent sharing of the energy, effectively converting all LWR into kinetic energy is a very short space and time.

3) Convection is the predominant method of transferring heat through the troposphere.

4) Radiation transmits the energy above the troposphere, with ever widening radiation windows with altitude.

5) The back-radiation from the atmosphere to the surface is both fixed and minimal for any level of atmospheric CO2 and other photon-absorbing gases.

  1. Roy Clark says:

    I reach similar conclusions in two different ways.

    1) A real thermal engineering analysis of the surface energy tranfer using measured flux numbers and the surface thermal properties.

    2) Do the line by line spectral calculations with data from the HITRAN database.

    What surface temerpature is your model really predicting?

    Gravity rules over the photons in the greenhouse effect.—guest-post-by-roy-clark-201.php

  2. You should do an article on Climate Modeling through Radiative-Convective Models, V. Ramanathan and J.A. Coakley, Reviews of Geophysics and Space Physics (1978)

    Their paper currently available free here.

    And explain the difference between the standard approach and this new paper.

  3. David says:

    How much of CAGW theory is based on the “T” factor of energy in the atmosphere?
    I see it basically like a freeway. If the incoming traffic (TSI) is constant, but the speed of certain cars reduced by the cops (GHG) the total traffic, (energy/ temperature) increases.

    In the above the atmosphere is the freeway, and the TSI is incoming traffic. GHG are the cops that slow down certain red sports cars, (LW radiation) thus increasing the energy or density of traffic on the freeway. However, our earth has more then just freeways. We have many side streets that reduce the speed (residence time of incoming radiation) of traffic more then anything on the freeways. (atmosphere),

    These slower streets are the land and Ocean, and what happens here effects the residence time (speed) of vehicles more then what happens on the freeways. A photon of SW radiation entering and penetrating the ocean slows down dramatically compared to the freeway of the atmosphere. So the total traffic flow (earths energy budget) depends on the time spent on all streets, not just the freeways, or atmosphere.

    If water vapor and clouds increases in the atmosphere, (more cops enter the freeways)
    less traffic enters the side streets, the oceans, and even though freeway traffic increases due to more freeway cops, side street traffic is more sparse (cooling) and TOTAL TIME
    in the traffic system is reduced even though the freeway traffic is temporarily increased.

    I am just trying to wrap my non science educated brain around this, so any thoughts helping me see if I am driving in the right direction here are appreciated.

  4. Bryan says:

    Yes this paper seems to tick all the boxes as regards careful handling of the available data.
    A conservative approach as used so as not to exaggerate the results.

    It will be quite interesting to see Roy Spencers reply

    Its good however that the paper is getting a wider coverage and John Nicol welcomes constructive criticism

    Here also is a paper that more people should read.
    Especially as it comes from a source with no “spin” on the AGW debate.

    The way I read the paper is it gives massive support for the conclusions of the famous Woods experiment.

    Basically the project was to find if it made any sense to add Infra Red absorbers to polyethylene plastic for use in agricultural plastic greenhouses.

    Polyethylene is IR transparent like the Rocksalt used in Woods Experiment.

    The addition of IR absorbers to the plastic made it equivalent to “glass”

    The results of the study show that( Page2 )

    …”IR blocking films may occasionally raise night temperatures” (by less than 1.5C) “the trend does not seem to be consistent over time”

    Click to access penn_state_plastic_study.pdf

  5. Richard111 says:

    My guess is the author anticipated the request in the second post.

    “”No attempt has been made here to construct a model of atmospheric behaviour which relates in any way to the detailed structures of modern GCMs. The emphasis has been to try to understand the possible processes which can take place according to the well established laws of physics, beginning with the absorption of radiation by a selective gas and the subsequent, physically necessary, redistribution of that energy which may lead to increases in the temperature of the earth because of such absorption.””

  6. Richard111:

    You should read the Ramanathan & Coakley paper.
    It is a solution to the radiative transfer equations through a 1d vertical section in the atmosphere.
    A necessary precondition to calculate the effect of any radiatively-active gases.

    If you don’t solve the equation dI / dχ = (I – B), where I is radiation at a given wavelength and optical depth, B is emission, and χ is optical thickness – then how can you calculate the interaction of the atmosphere with terrestrial (and solar) radiation?

  7. Bryan says:


    ….then how can you calculate the interaction of the atmosphere with terrestrial (and solar) radiation?……..

    I suggest repeating Woods simple experiment.
    You might find the calculation is pointless as the radiative effect is almost negligable.

  8. Bryan:

    We measure the back-radiation (radiation from the atmosphere) at an average of 340 W/m^2.

    See The Amazing Case of Back Radiation – Part One. I know you already have seen this, you just don’t like the result.

  9. Bryan says:


    You don’t appear to want to look at the Woods experiment.

    It might shock you!

    However reality cannot indefinitely be ignored!

    After the Woods experiment look at the posting on the Polyethylene Tunnels above.
    These guys just want to grow bigger peppers and they couldn’t give a monkeys cuss about global warming one way or another!

  10. Re-examined?. It sounds like oneself conscience re-examen and remorse 🙂
    Anyway, Occidental culture’s original sin was Agnosticism.

  11. Dr T G Watkins says:

    Thanks for the post. I read it all and understood most at a superficial, limited level. This is the 3rd analysis by a physicist that has come to similar conclusions regarding the effects of CO2 on temp.
    Someone needs to tell the GCM programmers!

  12. Joe Lalonde says:

    Science and climate science in particular have made the error of studying only one area to the exclusion of all others. Individual areas that have boarders that cannot be crossed as traditional teaching from very young has instilled this as absolute fact from scientists, physicists, mathematicians, etc.
    Our planet and solar system does not follow mans rules or laws. It is an extremely complex and interacting system. Just look at all the different organs and complex systems are in the human body. This planet is just as highly complex with many different actions happening that can effect the whole.

    All the physically insignificant changes that are happening with this planet have been ignored by science. But when all the physical evidence is put together, it suggests that this planet is suffering from pressure build-up.

    The growth up mountains is pressure rising from the atmosphere.
    Blamed on global Warming but the cold atmospheric winds at those levels would keep areas too cold unless the pressure pushed those winds up.

    Most people would say that heat rises. Okay, then why is the pressure changing the surface salt on the oceans at only a couple inches and is expanding since 1970.

    Science made a huge error in following the theory that global warming has caused the salinity in the oceans to change. No one double checked with science as to how a warming planet cannot possibly change the ocean salinity. They just followed the conclusions as it all fell into the Global Warming gambit. Oceans have been rising steadily 3mm a year so if anything, the salinity should be diluting slightly. The only way heat can change ocean slinity would be a massive amount of evaporation to concentrate the salt. But this would effect ALL the salt in the water and not just a couple of inches of surface salt. The changes of balanced gases has been an increase if heavier CO2 gases that mostly stay near the surface. Water in compressed gases of hydrogen and oxygen but has a complex ability to include salt and trace elements.

    A cook could have told scientists their theory of salinity changes sucked.
    Funny thing is the U.S. government had this researcher testify to her theory on Global Warming causing salinity changes.

  13. Leonard Weinstein says:

    I agree with points 1,3,4,and 5. 2 is dead wrong. Nearly the same amount of re radiation out at a given altitude occurs as the absorbed radiation. The adiabatic lapse rate (maintained by atmospheric mixing) results in the temperature slowly decreasing with increasing altitude. Now LTE exists, so other gas collisions with water vapor, CO2 and other atmospheric absorbing AND EMITTING molecules cause continuing emission at the local effective temperature. Since the temperature is dropping with altitude, the outgoing radiation is slightly higher that back radiation, so the net is a reduced RADIATION flux compared to radiation through an optically transparent atmosphere. Thus most of the heat transfer from the surface AND from atmospheric absorption of incoming sunlight is eventually carried to the upper atmosphere by convection.

    Point 4 now enters the picture. The radiation to space is from the upper atmosphere, but it is all from the optically absorbing and re radiating gas, i.e., the atmospheric greenhouse gases (water vapor, CO2, and etc.). While data seems to show that the upper atmospheric water vapor level is not increasing as CO2 level increased, nevertheless the upper atmospheric CO2 level has increased. This means the altitude where the outgoing radiation goes to space is slightly raised due to the extra CO2. The effective altitude of outgoing radiation is what sets the surface temperature. The lapse rate is a temperature gradient, and is not dependent on anything but gravity and gas thermal properties. The temperature of the surface is the temperature of the atmosphere at the effective altitude of outgoing radiation plus the lapse rate times the altitude. Increasing the altitude of outgoing results in a warmer surface than otherwise.

    The issue is made more difficult by the possibility of feedbacks. For example, if CO2 made a small temperature increase, and this caused more surface evaporation, how would that change the result. The answer is that we are not sure. It is fairly clear the high altitude water vapor has not been added to the CO2, so that is not a positive effect. It seems cloud cover is the biggest uncertainty, as that changes the amount of absorbed sunlight (albedo effect). The best I can tell is that there is probably a negative feedback from clouds, so the direct CO2 effect is there, but reduced, and very small.

  14. Leonard Weinstein says:

    Correction to my previous post. I do not agree with his statement 5. If there were no atmospheric greenhouse gases or water droplets, all radiation from the warm surface would be directly to space and would equal all of the absorbed solar radiation. For significant amounts of atmospheric greenhous gases, the back radiation would be close to the emitted radiation, and convection would be the dominant mode of heat flux to the TOA. These two extremes are examples why he is wrong.

  15. Bryan says:

    By coincidence I was reading Roy Clark’s paper(excellent) before finding the John Nicol paper(excellent) on tallbloke’s site.

    They come to very similar conclusions.

    Both use all the methods of heat transfer (including radiative transfer) in the atmosphere and find that there is very little to support the current IPCC view of CO2 as a real and present danger to mankind.

    Gerlich & Tscheuschner came to the same conclusion following fundamental thermodynamic reasoning.

    The simple Woods experiment has now been confirmed by more advanced theoretical considerations.

    SoD claims he has not seen the Woods paper even though it is included in the Gerlich & Tscheuschner paper which he claims to have read.

  16. Leonard Weinstein says:

    All of the quoted papers miss the whole point of what the atmospheric greenhouse gas effect is. Some of their analysis is valid, but incomplete. Some is just misleading, and some is just wrong. It is real and the actual whole issue hinges on what are the effective feedback effects. I and Roy and some others think it is a negative feedback, so the temperature gain is small. The CAGW people think it is large. The next few years of real world data will show who is probably correct.

  17. Tenuc says:

    I found the paper by John Nicol, “Climate Change (A Fundamental Analysis of the Greenhouse Effect)” is an excellent document to explain the real role of water vapour, CO2 and other ‘green house’ gases regarding weather/climate.

    It is clear that Earth’s heat engine is driven via the hydrological cycle, which depends on the sun to provide the energy to do the work of driving climate. Water can exist in 5 distinct forms (solid, liquid, cloud (liquid drops), cloud (ice spicules). Each form has different effects on the system and controls the amount of energy available to do work. This acts as a powerful ‘homoeostat’, which prevents the system getting too hot or too cold, and produces the quasi-cyclic nature of climate which is observed.

    CO2 has little or no effect on weather/climate as water in it’s many is the ultimate control system.

  18. suricat says:


    I intended to make a post reply in this thread, but the responses you’ve accepted ‘in this thread’ make it impossible.

    Please make the ability for a response to your posts more ‘ameiliable’ to the subject/discussion at hand.

    Best regards, Ray Dart.

    [Reply] Hi Ray, I’m a one man show and the way the system works is that once I’ve approved someone’s first post, they can post freely. 🙂

    Feel free to contribute your thoughts, or not, as you wish.

    I will use this opportunity to ask everyone to make an effort to stay on topic though. Come on guys, there is an open thread for off topic discussion!

  19. Joe Lalonde says:

    40 years ago, we were given a warning by the start of the salt changes.
    How much more time is left before the warning is up.

    And we havent done a thing about it.

  20. Bryan says:

    Leonard Weinstein

    Thanks for the reply.

    You say you agree with much of the John Nicol paper but that point 2 is wrong

    …”2) 99% of the absorbed photons are not re-emitted, due to collisions with other molecules and the consequent sharing of the energy, effectively converting all LWR into kinetic energy is a very short space and time.”…….

    A photon being absorbed by CO2 molecule say 4um, or more likely 15um, has much more energy than the translational KE of the molecule.

    Most agree that this energy is rapidly thermalised by the 10^10 collisions per second that the molecules experience.

    However to re emit the molecule now has to acquire a statistically unlikely value of translational KE.

    I personally would not have put the figure as high as 99% perhaps in the region of 80% but then I have not gone into the issue as deeply as John Nicol has.

    What figure would you come up with and why?

  21. Bryan says:

    Leonard Weinstein

    Further to my post above

    Since at the temperature of around 15C most of the CO2 molecules will have their KE in the translational form, I would expect that virtually all CO2 molecules would be capable of absorbing the 15um and the 4um IR photons if provided.

    My calculations are based on the number of CO2 molecules getting enough KE to enable them to emit the equivalent energy as an IR photon

    Using Maxwell Boltzmann statistics to find molecules with sufficient KE to re-emit we get;

    4 emissions per hundred absorptions for the 15um photon.

    4um photon emission probability is 5 per million absorptions.

    Radiation arising from cloud or water droplet sources could then be added to get the “backradiation” figure.

    However Woods Experiment and the poly-tunnel paper above seem to confirm the conclusions of the papers of the 4 Physicists quoted above.

  22. Joe Lalonde says:

    1. A great majority of our science IS incorrect.
    Do they factor in everything or study one specific area?
    Do I have confidence in the Ice Core readings?
    No, that is someone interpretation of them.
    What they miss is a constantly changing planet.
    Ice cores go back what up to 4 million years out of 4.5 billion years?
    Water has a very fascinating relationship with salt concentrations and the constantly changing factors that keep changing the water as well. Our planets rotation has slowed in that time which means that the centrifugal force was grater as well. Our planet was also closer to the sun. So, the salt concentrations had to be much greater or we would NOT have water.
    Why does Mars not have water today? Lack of salt concentrations.
    Ice Ages are never the same each to the same factors.
    1. What prompted evolution from water mammals into land mammals?
    The evaporation process. THERE WAS NO WATER ON LAND BUT HEAVILY TRAPPED SALTED WATER! The geology shows much sand and rock and little else. Much later plants and animals came when the evaporation process was changing the salt process.
    Quite a partnership with atmospheric pressure as a cooling mechanism.

  23. Tenuc says:

    Joe Lalonde says:
    October 29, 2010 at 12:07 pm
    “1. A great majority of our science IS incorrect.
    Do they factor in everything or study one specific area?

    Spot on Joe! The focus on specialisation is preventing progress in many areas of science and leading to observational results being subsumed by computer models based on assumption generated by unfalsifiable conjecture.

    This is especially true for large scale non-linear systems, like the climate and the sun, where there is a dearth of generalists with a background in meteorology, physics, chemistry, biology, chaos theory e.t.c. We need better tools to understand how deterministic chaos can produce the phenomenon we observe and are in need of an ‘Einstein’ to identify some of the unknown unknowns.

    Until this happens the world can be held to ransom by unfalsifiable theories of catastrophic man-made CO2 driven global warming and other manifestations of cargo cult science. The truth is often hard to find, but it is worth the investment as it provides a solid platform for future research.

  24. @Dear Tenuc:
    We have to get back to simplicity!!. The church told us, more than two thousand years ago, that we were not supposed to comprehend anything, Gnosis was forbidden, only through alms and obedience we could manage our desperate lives…Well this keeps on going right now. But where is it real Knowledge??. It is everywhere used to say the Alchemists but we do not see. Thus symbols are interpreted as a kind of “literature” or, worst, “folklore”, as it could be possible for any “folk” to suddenly become illuminated as an individual can through trying to find knowledge. After being really “found by knowledge” one may understand that it was a complete lie that in order to know some fundamental laws of the cosmos, one should have to get entangled in trans-dimensional strings or being sucked by a gigantic black hole or being blessed by a distinguished Nasa astrophysicist, one of those who do not know really what the cycles of the Sun are, or even deny that that thing up there heat us !!
    I met knowledge recently, while reading Tallbloke’s post on “Gravity an unsettled issue”
    and in finding it I am surprised of having found its close relations with symbols known from centuries, as the egyptian cross “Ankh”, the double cross of Lorraine, the famous Pythagorean “Y”, the islamic “qubt” ( cube) guarded by two Imams (Iman-pronounced eemahn in spanish, meaning Magnet), , etc.,etc. which meant that these are not representations but actual “blue prints” of working laws.
    I invite you to see it:

  25. Tenuc says:

    Adolfo Giurfa says:
    October 29, 2010 at 7:47 pm
    “We have to get back to simplicity!!…

    …I met knowledge recently, while reading Tallbloke’s post on “Gravity an unsettled issue”
    and in finding it I am surprised of having found its close relations with symbols known from centuries, as the egyptian cross “Ankh”, the double cross of Lorraine, the famous Pythagorean “Y”, the islamic “qubt” ( cube) guarded by two Imams (Iman-pronounced eemahn in spanish, meaning Magnet), , etc.,etc. which meant that these are not representations but actual “blue prints” of working laws.
    I invite you to see it:

    Thanks Adolfo – Downloading right now!

  26. Joe Lalonde says:

    There is only a handfull of people who actually following the science trail to wherever the science will take them. It is such a huge area because of the vast complexity involved.
    I gained a vast amount of knowledge in planetary rotation and energy interaction plus studying the water evolution trail.
    Originionally I was looking at the difference between salt water density and freshwater density for power generation when curiousity and many inaccuracies were occuring.
    Theories were blown apart when applying them to the past differences in rotation and the energies being recreated at that time.

    Just following the time line of Ice Ages and our planet only has about 5 millions years left before it will be frozen solid due to the water changes with the planetary slowdown.
    Water is constantly shedding salt to stay in balance with the atmosphere pressure.

  27. Joe Lalonde says:

    Have you noticed that math and formulas are only for that stationary time period?
    They do not include changes unless periodically you change the formula.
    Infussion and release of energy was missed by science.

  28. Joe Lalonde says:


    Sorry I was incorrect. It is centrifugal force that the salt is adjusting with.

  29. Leonard Weinstein says:

    Reply to Bryan says:
    October 29, 2010 at 9:12 am
    First, the energy of 15 micron photons is about 1.3E-20 J. Second, the kinetic energy of a thermalized CO2 molecule at 20 C is about 1.3E-20 J. Third, the equa partition of energy in a molecule results in vibrational energy level being about the same as kinetic energy. Your argument fails on every point. The number of absorbed and emitted photons of LTE gases is about the same on average.

  30. Bryan says:

    Leonard Weinstein

    Thank you for your reply

    I would ask you to calculate the figure you have calculated for the Translational KE

    I make the value to be 6 E-21J

    Giving Ephoton/KE =2.21

    Or for the Temperature of 15C I quoted in my post above Ratio = 2.22

    So the ratio of the numbers of co2(Np) with extra energy to release photon/number of average co2(Nt) and yet have average translational KE left

    =Np/Nt=e^-(Ep – Et) = e^-3.2 =0.04 or 4%

    The ratio of CO2 particles with enough KE to release photon and then stop dead

    =Np/Nt=e^-(Ep – Et) = e^-2.2 =0.11 or 11%

    So we find the number emitted is much less than the number absorbed which is consistent with what I have said.
    The same analysis works for the 4um photon.

    In the John Nicol paper he probably used the more realistic atmosphere temperature of say -10C which could possibly come up with the 1% emission figure.

    You say ….”Your argument fails on every point”……

    My post included the Woods experiment do you consider this experiment as a failure?

  31. Zeke the Sneak says:

    tallbloke replies: “I will use this opportunity to ask everyone to make an effort to stay on topic though. Come on guys, there is an open thread for off topic discussion!”

    That’s a bit like herding cats, isn’t it. 😀
    Perhaps one open thread is not enough. Great blog, great posters.
    Zeke the Sneak

  32. Leonard Weinstein says:

    I redid the thermal kinetic energy more carefully, and you are correct on 6E-21. However, there is a velocity distribution, and also collision of molecules near head on, so a significant number can emit at the required energy level. Also I have not done the numbers yet, but obviously the number of absorbed photons from layer to layer is about equal to the emitted photons. Those molecules that emit, are then (by the large number of collisions) re energized in a very short time by the surrounding non greenhouse gases. You do not need to absorb to emit, only to be surrounded by the warm gas. Those that absorb a photon give the excess energy up by mode redistribution and collision. The number absorbed and emitted are independent! If you has a thin gas layer with some CO2, and it was surrounded by CO2 free gas, the CO2 containing layer would be emitting and not absorbing as long as it was at a temperature with some molecular velocities in a range to give the required energy.

    I have not read the Woods experiment yet, but will do so and comment later.

  33. Leonard Weinstein says:

    I assumed in the above argument that almost all of the energy was transported by convection due to back radiation acting as a radiation effective insulator. The gas temperature variation is due to the adiabatic lapse rate, generated by the convection. Under these circumstances, the net radiation flux is very small compared to convected energy and the gas temperature is in LTE and not determined by radiation. This is the condition for my assumption of absorption and radiation being near equal. Proof of the assumption is clearly seen on Venus.

  34. Bryan says:

    Leonard Weinstein

    Thank you for your reply

    When first confronted by the absorption of radiation in the atmosphere such as 4um and 15um if someone had asked me to guess about the relative size of the energies of the CO2s translational KE verses the Photon energy I would have come up with the wrong answer.

    The 4um radiation is almost 9 times the Translational KE!

    At temperatures of around 290K its safe to say that almost all CO2 molecules will have no vibrational or rotational components.

    So each molecule is “available” to absorb suitable radiation.

    Instantly after absorption has taken place the enhanced molecule has about 3 times the energy of neighbouring N2 and O2 neighbours in the 15um case.

    Following a “folksy” analogy its like the lottery winner who discovers he has lots of new friends to share his winnings.

    In a very short time the extra energy is shared out.

    What is hard for me to understand is the reverse happening!

    For a CO2 molecule to pick up enough excess translational energy to re-emit!

    Difficult, but not impossible as you say.

    For the 15um a “head on” collision between two molecules gets you almost there.

    But what is the probability of that?
    The probability of re-emission of a 4um photon is extremely remote!

    Now it seems a good idea to examine the night time situation for any greenhouse effects.
    Because daytime atmospheric radiation could be “backradiation” or direct from Sun through several interactions as it made its way to the Earth surface.

    However at night time as temperatures drop the probability of emission is decreased.

    Woods Experiment and the poly-tunnel paper above seem to confirm the conclusions of the three papers by Roy Clark,John Nicol and G&T .

    Even more impressive is the fact that all three papers used different methods to arrive at similar conclusions.

  35. Take a look at Theory and Experiment – Atmospheric Radiation where the conventional radiative transfer theory is compared with experimental results and some deficiencies in this paper are explained.

  36. Bryan says:


    You really should put some time aside to study;

    The experiment experiment by Wood and the poly-tunnel paper below.

    Continually going to sites and trying to redirect their readers to your own site is a bit odd.
    Engage properly and answer why you have not managed to find a few minutes to read the famous experiment by Wood

    Woods Experiment and the poly-tunnel paper above seem to confirm the conclusions of the three papers by Roy Clark,John Nicol and G&T .

    Even more impressive is the fact that all three papers used different methods to arrive at similar conclusions.

    Click to access penn_state_plastic_study.pdf

  37. Bryan:

    Your argument is that we should ignore the match between standard theory and a huge amount of matching experimental results because one experiment 100 years ago that didn’t measure any of these values is apparently in support of your ideas?

    John Nicol doesn’t support your ideas because he agrees that the inappropriately-named “greenhouse” theory is correct.

    He believes that atmospheric radiation increases the surface temperature above what it would otherwise be.

    He doesn’t believe that increasing CO2 will increase surface temperature because of ideas about saturation. Or he doesn’t think he does – he has some contradictory conclusions. He appears not to understand radiative transfer theory, but it’s hard to be certain.

  38. Bryan says:


    Says of me;

    …..”John Nicol doesn’t support your ideas because he agrees that the inappropriately-named “greenhouse” theory is correct.”…….

    But what do we find in the bullet points at top of thread!

    5) The back-radiation from the atmosphere to the surface is both fixed and minimal for any level of atmospheric CO2 and other photon-absorbing gases.

    What is becoming ever clearer that SoD refuses to read and try to refute the experiment by Wood.

    Evasion and trying to change the subject is pointless.

    Wood has often been described as the best experimental Physicist that America has ever produced, exactly the kind of person not to ignore.

    Being like an Ostrich and refusing to examine the evidence in an open minded way leads nowhere!

  39. Bryan:

    This will be my last response to you on this blog.

    This blog article is about Dr. Nicol’s paper. Evasion would be avoiding discussion about Dr. Nicol’s paper.

    Read his paper, not the bullet points at the top of the thread.

    What is amazing is to watch you support his paper when he believes in the inappropriately-named “greenhouse” theory. (Which you believe is contrary to basic physics).

    I don’t agree with him. Not because he believes in the “greenhouse” theory, but because his paper has many flaws and doesn’t really explain how he arrives at his solution. It does seem as if he doesn’t understand the subject but I can’t be certain due to the lack of information and contradictory ideas in his paper.

  40. Bryan says:


    The title of the thread is;

    John Nicol: Greenhouse Effect re-examined

    Wood concluded that the so called “greenhouse radiative effect” had no physical basis.

    John Nicol confirms this with a theoretical analysis

    ..”5) The back-radiation from the atmosphere to the surface is both fixed and minimal for any level of atmospheric CO2 and other photon-absorbing gases.”….

    Science should not be an ego trip.

    If something contradicts an idea you have, examine the evidence carefully.
    If you find yourself in error correct your view of the world.

    You will benefit from such an approach.
    It is called the Scientific Method.

  41. Leonard Weinstein says:

    Wood’s paper is not related to the atmospheric greenhouse problem, so don’t waste my time pointing it out. Also the poly-tunnel is not related to atmospheric greenhouse gas effects either. Those are both trapped convection issues.

    A simple refutation to Nicol can be most easily seen at Venus. The hot ground absorbs about 17 W/msq of sunlight. Some additional energy may be convected down from atmospheric adiabatic compression of solar energy absorbed higher in the atmosphere. The total solar radiation absorbed in the atmosphere and ground is about 170 W/msq due to the high albedo of Venus (due to the clouds). Nevertheless the surface is about 480 C (753 K). It is a near black body radiator at these conditions, so radiates just over 18,000 W/msq. If the gas absorbed over 18,000 W/msq and convected this to the upper atmosphere then radiated to space, where is the input for the 18,000 W/msq? I am very certain it ‘s not volcanic. Back radiation almost exactly balances radiation out to accomplish this, acting as a radiation insulator, but still allowing for convection. In fact the balance is so close that convective mixing maintains the adiabatic lapse rate, and the 170 W/msq of sunlight absorbed by the atmosphere plus ground is the amount radiated to space.

    Earth has a far smaller atmospheric greenhouse gas composition, and total thickness, so the effect is far smaller for Earth than Venus. However, the basic mechanism is the same.

  42. Bryan says:

    Leonard Weinstein

    ……..”Wood’s paper is not related to the atmospheric greenhouse problem, so don’t waste my time pointing it out. “……..

    To paraphrase Karl Marx;

    Those who do not learn from experiments will be forced to repeat them.

    The classical (wrong) explanation of the glass greenhouse was enthusiastically adopted by climate science until it was proved false.

    However you will still have to face up to the awkward fact that glass and IR treated polyethylene are far better absorber/emitters of IR radiation than CO2 or H2O.

    Yet they produce a radiative effect so small that it can be effectively ignored.

    4 physicists of good standing come by separate paths to the same conclusion and one that is fully in accordance with observed reality.

    Perhaps you feel that if you ignore the Woods experiment it will go away.
    That like much of climate science is wishful thinking!

  43. […] other blog I’ve been firefighting on is Science of Doom. S.o.D. visited here a while ago and joined in the debate on the John Nicol thread. Prior to that, I’d had a discussion with S.o.D. regarding the […]

  44. Bryan,

    Leonard Weinstein and ScienceofDoom can only spout the official nonsense of a completely unphysical, huge surface radiation and atmospheric back radiation (which violate the conservation of energy), all because they see no problem with calling the surface a blackbody, which those of us who are competent physicists (that’s all it takes, competence) know is also physical nonsense. I won’t even bother giving my “atmospheric heat transport for dummies” post here. The only thing that will win the day is to wait and watch the temperature go down according to the “solar activity plus ocean oscillations” crowd’s predictions (although it’s already levelled off for the last decade, completely invalidating the greenhouse hypothesis). LW and SOD are literally not worth talking to, as I’m sure you have seen here.

  45. tallbloke says:

    Hi Harry, and welcome. I don’t mind people venting a bit or expressing themselves forcefully, but take it easy with getting personal.

    Here’s what prof. Arnold Gordon, a man with 130+ published papers on oceanography has to say:

    Energy absorption and emission from the ocean:

    Solar Radiation: Much of the direct and diffuse solar short wave (less than 2 micros, mostly in the visible range) electromagnetic radiation that reaches the sea surface penetrates the ocean (the ocean has a low albedo, except when the sun is close to the horizon), heating the sea water down to about 100 to 200 meters, depending on the water clarity. It is within this thin sunlit surface layer of the ocean that the process of photosynthesis can occur. Solar heating of the ocean on a global average is 168 watts per square meter.

    Net Back Radiation: The ocean transmits electromagnetic radiation into the atmosphere in proportion to the fourth power of the sea surface temperature (black-body radiation). This radiation is at much longer wavelengths than that of the solar radiation (greater than 10 micros, in the infrared range), because the ocean surface is far cooler that the sun’s surface. The infrared radiation emitted from the ocean is quickly absorbed and re-emitted by water vapor and carbon dioxide and other greenhouse gases residing in the lower atmosphere. Much of the radiation from the atmospheric gases, also in the infrared range, is transmitted back to the ocean, reducing the net long wave radiation heat loss of the ocean. The warmer the ocean the warmer and more humid is the air, increasing its greenhouse abilities. Thus it is very difficult for the ocean to transmit heat by long wave radiation into the atmosphere; the greenhouse gases just kick it back, notably water vapor whose concentration is proportional to the air temperature. Net back radiation cools the ocean, on a global average by 66 watts per square meter.

    Conduction: When air is contact with the ocean is at a different temperature than that the sea surface; heat transfer by conduction takes place. On average the ocean is about 1 or 2 degrees warmer than the atmosphere so on average ocean heat is transferred from ocean to atmosphere by conduction. The heated air is more buoyant than the air above it, so it convects the ocean heat upward into the atmosphere. If the ocean were colder than the atmosphere (which of course happens) the air in contact with the ocean cools, becoming denser and hence more stable, more stratified. As such the conduction process does a poor job of carrying the atmosphere heat into the cool ocean. This occurs over the subtropical upwelling regions of the ocean. The transfer of heat between ocean and atmosphere by conduction is more efficient when the ocean is warmer than the air it is in contact with. On global average the oceanic heat loss by conduction is only 24 watts per square meter.

    Latent Heat: The largest heat loss for the ocean is due to evaporation, which links heat exchange with hydrological cycle (Fig. 4). On global average the heat loss by evaporation is 78 watts per square meter. Why so large? Its because of the large heat of vaporization (or latent heat) of water, a product of the polar bonding of the H2O molecule, as discussed in the Ocean Stratification lecture. Approximately 570 calories (2.45 x 106 joules) are needed to evaporate one gram (kilogram) of water! A gram of water is roughly one cubic centimeter, amounts to a loss of one centimeter of water per a square centimeter of ocean surface area. The water vapor leaving the ocean is transferred by the atmosphere eventually condensing into water droplets forming clouds, releasing its latent heat of vaporization in the atmosphere, usually quite remote from the site of the evaporation, thus representing a significant form of heat transfer, later heat transfer.

    The annual heat flux between ocean and atmosphere (Fig. 5) is formed by the sum of all of the heat transfer process: solar and terrestrial radiation; heat conduction and evaporation. While the ocean gains heat in low latitudes and losses heat in high latitudes, the largest heat loss is drawn from the warm Gulf Stream waters off the east coast of the US during the winter, when cold dry continental air spreads over the ocean. An equivalent pattern is found near Japan, where the Kuroshio Current is influenced by the winter winds off Asia. It is in these regions that the atmosphere takes over as the major meridional heat transfer agent.

    More here;

  46. Bryan says:

    Harry Dale Huffman

    Leonard Weinstein is normally worth listening to.

    I was a bit disappointed by his dismissal of the famous experiment by R W Wood.

    To sum up his ideas briefly he thinks there is a “greenhouse effect” .

    But thinks that its effects will not lead to the scenario that the IPCC worry about.

    His take on climate appears to be that the convective transfer of heat dominates and determines the climate conditions as we know them hence doesn’t seem too worried about radiate effects.
    As you are a Physicist I think you will appreciate this recent careful paper Gerhard Kramm and Ralph Dlugi

    er, greenhouse effect and transient
    climate response usually related to the globally averaged energy balance model of Schneider and
    Mass. After scrutinizing this model and the corresponding planetary radiation balance we state
    that (a) the this globally averaged energy balance model is flawed by unsuitable physical
    considerations, (b) the planetary radiation balance for an Earth in the absence of an atmosphere is
    fraught by the inappropriate assumption of a uniform surface temperature, the so-called radiative
    equilibrium temperature of about 255 K, and (c) the effect of the radiative anthropogenic forcing,
    considered as a perturbation to the natural system, is much smaller than the uncertainty involved
    in the solution of the model of Schneider and Mass. This uncertainty is mainly related to the
    empirical constants suggested by various authors and used for predicting the emission of infrared
    radiation by the Earth’s skin. Furthermore, after inserting the absorption of solar radiation by
    atmospheric constituents and the exchange of sensible and latent heat between the Earth and the
    atmosphere into the model of Schneider and Mass the surface temperatures become appreciably
    lesser than the radiative equilibrium temperature. Moreover, neither the model of Schneider and
    Mass nor the Dines-type two-layer energy balance model for the Earth-atmosphere system, both
    contain the planetary radiation balance for an Earth in the absence of an atmosphere as an
    2 asymptotic solution, do not provide evidence for the existence of the so-called atmospheric
    greenhouse effect if realistic empirical data are used.

    Click to access 1002.0883.pdf

  47. Leonard Weinstein says:

    In order to understand the experiment of Wood, you have to understand what was thought to be happening, and what he demonstrated.
    What was thought to be happening:
    People thought an enclosed chamber with a glass (or clear plastic) enclosure passed short wave solar radiation into the enclosure, where it heated the bottom by absorption. This hot surface then radiated long wave radiation up which was absorbed by the enclosure (which was opaque and a near black body to the long wave outgoing radiation). This was then radiated both out and back to the enclosure, so in effect trapped some energy. i.e., back radiation heated the enclosure.
    What Wood showed was happening:
    Nearly the same heating would occur if the enclosure was opaque to incoming radiation, so the assumption was wrong.
    What is actually happening:
    Whether the interior is heated or the exterior is heated by sunlight, this heats the air trapped in the enclosure. Back radiation happens, but is not of any consequence to the effect. All back radiation is doing is acting as a partial radiation insulator, but the convective heat transfer totally dominates this enclosure problem, and the inability of the heated air to escape when it is heated is why the enclosure heats up.

    The atmospheric greenhouse gas effect is a totally different problem. Again the backradiation due to the absorbing and radiating gases (water vapor, CO2, etc.) is doing nothing but acting as a radiation insulator, but convective transfer of the heated Earth energy caries the energy to the upper atmosphere where it is radiated to space. It is the adiabatic lapse rate that heats the Earth, but this is only possible due to the transfer of the location of radiation to space to a higher altitude. If the atmosphere did not have any atmospheric greenhouse gases (and without water vapor, there would be no clouds), the radiation to space would be directly from the surface, and it would be colder. There would still be a lapse rate, but the entire atmosphere would be colder.

  48. Leonard Weinstein says:

    I want to clear up a misunderstanding you seem to have. When a absorbing gas absorbs a photon, it give that energy to the surrounding gas by collisions. However, emitted photons do not have to be, and in fact are not generally the same energy as the absorbed ones. They are generally somewhat lower energy (longer wavelength) due to a continual dropping temperature with altitude. The wavelength is determined by available vibration energy states and local temperature. If no available states are within the range of possible collision energy levels, you are correct that emission can’t occur, but there is always a wide range of velocities and many energy states at any realistic atmosphere temperature, and many collisions per sec, so for realistic temperatures, there will be thermal emission from those gases. If the frequency of absorbed photons is far different, then the radiation will tend to warm the gas, but this would tend to make it rise, cooling from adiabatic expansion. However, for Earth (and Venus) the radiation flux rate is far smaller than convective heat transfer and mixing, so the radiation has little direct effect on the atmosphere other than the raising of altitude for radiation to space.

  49. tallbloke says:

    Nice clear coments Leonard, thankyou.

    I wonder if the height of the tropopause has been affected by the shrinking of the Ionosphere noticed by NASA recently. That would seem to be related to solar activity levels.

    I further wonder, if that is the case, whether the correlation I found between specific humidity at the 300mb level (near the tropopause) and solar activity is an artifact of such a raising and lowering.

  50. Bryan says:

    Leonard Weinstein

    Thank you for your reply.

    I agree almost entirely with your post of November 13, 2010 at 11:13 pm.
    I remember when you set out these points in SoDs site with William C Gilbert and in my opinion this explanation is correct.
    My point about raising the question of Woods experiment was to underline the fact that the radiative effect is so small, in contrast to the convective heat transfer, that it is almost unnoticeable.
    This paper below came to the conclusion that it was pointless to add IR blockers to polyethylene thus confirming R W Wood.
    The research of course was aimed at producing bigger peppers and perhaps the researchers had never heard of R W Wood.

    Click to access penn_state_plastic_study.pdf

  51. Bryan says:

    Leonard Weinstein

    I agree with most of your post of November 13, 2010 at 11:28.

    Some folk however would like to argue that if the atmosphere absorbs a certain number of 15um photons it must emit exactly the same number of 15um photons.

    I agree that it is more probable that the radiation will be of longer wavelengths.

    This seems to follow the pattern of Solar => Earth surface => atmosphere =>space with the radiation wavelength getting longer on each interaction.

  52. Leonard Weinstein says:

    To all,
    I am a skeptic, and scienceofdoom is a supporter of CAGW. However, he is a very knowledgeable and also a very polite person. I happen to agree with most of what he says, except for the large feedback from CO2. Please refrain from name calling or making negative remarks when you are not being personally attacked. It makes reasonable people with different points of view think skeptics are a bunch of savages (and there are a few). I realize many supporters of CAGW have started many of the bad remarks, but if we are right, we should not reply in turn, and the badmouths will look worse for it.

  53. Bryan says:

    Leonard Weinstein

    On SoD.

    ….”However, he is a very knowledgeable and also a very polite person. I happen to agree with most of what he says, except for the large feedback from CO2. Please refrain from name calling or making negative remarks when you are not being personally attacked.”…

    I m glad that you found SoD unfailingly polite, on the other hand some of us have found a different SoD.

    I regard myself as a polite person however I reserve the right to reply in kind if SoDs lack of good manners is directed at me.

    How do you know SoD is a ” he”?

  54. tallbloke says:

    I think S.o.D. may have decided that the easiest way to deal with my take on the science is to stop engaging with it. 🙂

    S.o.D. takes uncontroversial points of science and presents them as if they somehow support or vindicate the AGW hypothesis with strong evidence for it.

    Nothing could be further from the truth.

    However, S.o.D. says these simple aspects of uncontroversial physics need to be addressed before moving on to the real meat.

    Can’t wait.

  55. Leonard Weinstein says:

    There is a CAGW supporter that goes by the handle of SoD. This is NOT scienceofdoom, who always uses the full form. SoD is a nasty individual, but keep the two separate. I have corresponded with scienceofdoom, so know it is a he. I had a long and useful debate on scienceofdoom’s website, and he is always reasonable and polite, even when I disagreed with him on some points. Visit his website for a better understanding. He has considerable useful information.