Doug Cotton: Radiated Energy and the Second Law of Thermodynamics

Posted: March 13, 2012 by Rog Tallbloke in atmosphere, climate, Energy, Kindness, Ocean dynamics

I have been asked by Doug Cotton to draw attention to the paper he has written. I’m happy to do so, despite some personal reservations regarding some of the inferences drawn from observations. I request that all comments are polite, and kind-hearted. Everyone is learning about radiation, the process is ongoing.

Radiated Energy and the
     Second Law of Thermodynamics
Douglas Cotton, B.Sc., B.A., Dip. Bus. Admin
March 12, 2012


The transfer of thermal energy by radiation is discussed in the context of the Earth’s
surface and its atmosphere. When considering what happens as the Sun is warming
the surface each morning, it is noted that its radiation is being directed onto the land
surfaces and some distance below the surface of the oceans. So, additional radiation
supposedly transferring further thermal energy from the cooler atmosphere to the
warmer surface would violate the Second Law of Thermodynamics. This law must
apply (on a macro scale) between any two points at any particular time. An apparent
violation cannot be excused on the basis of “net” radiation, because “net” radiation has
no corresponding physical entity and is meaningless and useless for determining heat
flow in situations when other processes are also involved.

It may be deduced that none of the radiation from a cooler body (and only a portion of
the radiation from a warmer body) has any thermodynamic effect on the other body.
All such radiation from a cooler source is rejected in some way, and it can be deduced
that resonance and scattering occurs without any conversion to thermal energy. The
radiation continues in another direction until it strikes a cooler target, which could be
in space.

Furthermore, the stability of sub-surface temperatures will tend to maintain the
observed close thermal equilibrium at the interface between the surface and the
atmosphere. Hence other heat loss mechanisms are likely to adjust, in order to
compensate for any reduced radiation.

Some commonly raised questions are answered in the Appendix, where there is also
discussion of temperature trends and climate cycles, as well as counter arguments for several possible objections to matters raised herein.

Full pdf here

  1. Doug Cotton says:

    Consider this: water vapour molecules are roughly 20 to 50 times more prolific than carbon dioxide molecules. H2O also radiates in many more frequency bands, so the radiation from each molecule must be several times as effective as that from a CO2 molecule. Put these facts together and all the water vapour is probably at least of the order of 100 times or more more effective than all the carbon dioxide molecules.

    Effective at what? Effective at slowing just the radiative component of surface cooling.

    But, wait there’s more!

    We measure “climate” in just the first 2m of the atmosphere because weather station specifications say thermometers should be in enclosures which are 1.5 to 2 metres above the ground.

    If radiation from the surface is absorbed at various altitudes and more of it where the temperatures are colder, what very small percentage is going to be absorbed in the first 2 metres?

    Could this very minute amount of the radiation which is playing a part in cooling the surface actually maintain that first two metres at a similar temperature to the surface itself? Hardly. Convection would take the energy up into the sky far faster.

    Now evaporation really doesn’t have much net effect. Why? Because most rain and snow returns to the surface at roughly the same temperature as the surface. This in fact is the only physical heat transfer from the atmosphere to the surface and, ironically, the IPCC diagrams don’t show it! Instead they show radiation transferring heat to the surface which it cannot do from a cooler atmosphere because entropy would decrease if it could.

    So what keeps the air we breathe at nearly the same temperature as the surface, day or night?

    Molecular collisions at the surface/air interface – otherwise known as conduction or diffusion.

    And carbon dioxide can have absolutely no effect upon the rate at which heat transfers from the surface to that air by such physical, non-radiative processes.

  2. Doug Cotton says:

    There’s an interesting experiment being discussed among my colleagues that demonstrates how radiation in a microwave oven passes right through the material in those plastic bowls shown in this photo and heats water inside just as quickly as it heats the water in the two glasses on the outside. Pour two glasses of water into the lower container and tape an identical container upside-down above it as shown. Operate the oven for 4 to 5 minutes and measure the temperatures of all the water. That in the glasses may even be a couple of degrees cooler.

    So, for those who think that low frequency radiation warms everything, this shows not that it is transmitted in the usual way (because the containers are opaque even to sunlight) but that the radiation undergoes resonant (or pseudo) scattering, which means some follows random paths and gets through to the other side. This confirms the existence of this scattering process which Prof Claes Johnson explained.

  3. Doug Cotton says:

    My paper has been cited in Joe Postma’s new paper, including a quote from myself pp 47-49.

    All should read Joe’s excellent publication.

  4. Doug Cotton says:


    Those who still believe the carbon dioxide hoax need to come to realise that energy balance does not determine climate. It’s the other way round. Climate determines energy balance. Climate itself is determined by the incident solar energy which fluctuates in long term natural cycles probably related to planetary orbits.

    Earth’s surface temperature cools as heat from the Sun is transferred back to the atmosphere. This process is dominated by sensible heat transfer, not by radiation which accounts for less than 30% of such transfers.

    All that backradiation can possibly do (according to physics) is slow that 30% of cooling which is due to radiation. Meanwhile, the other 70% merely accelerates to compensate, thus leaving no net effect on the overall rate of cooling. What comes in from the Sun will get out again by one means or another. When there are long periods of natural warming there will of course be a build up of energy being retained. The thermometers tell us that, without even having to measure the energy balance. But the opposite is the case when cooling sets in.

    Backradiation is not the cause, because it cannot transfer heat to a warmer surface. It can only slow radiative cooling. See my peer-reviewed paper linked at the top of this thread, recently cited by Joseph Postma in his October 2012 paper.

    Doug Cotton


  5. JWR says:

    Following the paper by Joe Postma, please do read my paper:
    It deals also with the suggestions of Claes Johnson.
    Avoid two-way heat flow, it gives spurious absorption!

  6. Nabil Swedan says:

    Doug Cotton,

    I communicated with the designer, fabricator, and user of an AERI instrument used in the ARM Program. Here are the main points:

    1) The instrument measures equal radiations day and night for wave lengths longer than 5 microns.
    2) At night some of the measured radiations come from the instrument itself.
    When you calculate how much are the radiations from the instrument to the IR detector, you will find that it is around 200 W/m2. Therefore, at night, the measured backradiations are from the instrument itself and not from the atmosphere. Infrared astronomy, which is very accurate in measuring the downwelling infrared radiations, shows no IR backradiations from the atmosphere at night.
    Obviously we made a mistake in interpreting the data measured by the AERI instrument. You are more than welcome to conduct your own investigation, and I would be pleased to give you contact information to save you time.
    The concept of backradiations inherently adds energy to the atmosphere from nowhere, which is impossible. It is approximately equal to heating the atmosphere by 70 degrees centigrade above that of the surface. This is a huge energy term, in the order of 3.7E23 Joules, incorrectly added to the energy equation of the earth.
    We must discontinue using the concept of backradiations and move on to another that makes physical, scientific, and mathematical sense. And you should stop mentioning the backradiations term because backradiations do not exist.

  7. Doug Cotton says:

    Nabil – what you say is interesting, but what I am saying is that you are incorrect in saying that the concept of backradiation “inherently adds energy to the atmosphere from nowehere.” Instead, it is much more akin to light being reflected back and forth between two parallel mirrors facing each other. There is no gain in total energy of course, but still plenty of radiation in each direction. If you have water vapour molecules up there radiating, then that radiation will be in all directions. There is no doubt that such radiation from low clouds temporarily slows the rate of radiative cooling of the surface. So there must be some of it.

  8. Doug Cotton says:

    The last 14 years of world climate records clearly indicate that there has been no net warming since this time in 1998. That is, there has been no net accumulation of energy in the Earth system – probably a slight loss in fact. So net radiative imbalance at TOA must also have been in accord with a cooling climate, not a warming one.

    But all those energy diagrams and models “predicted” carbon dioxide would cause extra warming. If this fails to happen in 14 years, it can also fail to happen in the next 600 years, by which time I predict the world will be back at a minimum similar to the Little Ice Age.

    The reason the energy diagrams are wrong is because they assume (and clearly indicate) dual heat flows between the surface and the atmosphere. They imply that radiation always transfers heat in the same direction. They assume that, if the net heat transfer is from hot to cold, then all is OK. But the two processes they assume happen are independent. A heat flow by radiation from the cooler atmosphere to the warmer surface does not force a greater flow of radiation out of the surface which is due to the surface being warmed more. Any such preliminary warming, no matter how infinitesimal, would be a violation of the Second Law of Thermodynamics.

    The only possible correct physical explanation is that which I have summarised starting on p.47 of Joseph Postma’s October 2012 paper. My reasons for such are also therein.

    Unless and until scientists understand when and by how much radiation transfers heat, they will continue to fumble with hypothetical, invalid concepts which mislead the world with their carbon dioxide hoax.

  9. Nabil Swedan says:

    “Unless and until scientists understand when and by how much radiation transfers heat, they will continue to fumble with hypothetical, invalid concepts which mislead the world with their carbon dioxide hoax.”

    Doug, the climate researchers and scientists have been working on the subject for over a century and at a cost that has exceeded 50 billion dollars. If they have been unable to find an answer to your question with all of the resources and time provided, then when will they?

    They cannot all be stupid, there must be something wrong with the concepts themselves.

  10. Doug Cotton says:

    The concepts relating to transfer of energy by radiation left Einstein baffled all his life. The early physicists were indeed not correct in assuming there was two-way transfer of heat. It took the brilliance of Claes Johnson, Professor of Applied Mathematics, to analyse the process computationally and come up with a very different explanation – an explanation which, unlike that of the early scientists, did not involve a violation of the Second Law of Thermodynamics. My paper (linked at the top) was intended to help explain to the public the consequences of what Claes had shown. Like all new discoveries, it can be many years before they are accepted by a consensus.

    It is very clear that “scientists” can be very wrong (“stupid” if you like to call it that), as they have been in attributing warming to carbon dioxide and saying it acts like a blanket. Click here to see a net energy budget diagram which is on page 2 of my first website. Note that conduction is shown as 7% of incoming solar radiation, latent heat as 23% and the total from the surface is 51%. So this diagram implies (7+23)/51 or about 59% of energy from the surface is by other than radiation. I say 60% to 70% in fact because I believe, from other reading, that the diagram understates conduction and evaporation.

    Either way, it is clear that a lot of energy is not radiated from the surface but, instead, finds its way into the atmosphere via oxygen, nitrogen and water vapor molecules, not by photon capture in carbon dioxide molecules.

    Non-radiating molecules, mostly oxygen and nitrogen, thus act like an insulating blanket. Carbon dioxide does the opposite..

    When CO2 molecules do capture, they are more likely to then radiate that energy away, or transfer it by diffusion to cooler oxygen or nitrogen molecules. It can then diffuse to water vapor and be radiated away. Without radiating molecules (the holes in the blanket) things would get very hot up there. I assure you.

  11. Doug Cotton says:

    In Maxwell’s Theory of Heat on pages 244 & 245 he describes how a gas only absorbs radiation when it is cooler than the emitter. This is what Prof Claes Johnson has established computationally. It is the reason why energy in backradiation from a cooler atmosphere is not converted to thermal energy in a warmer surface, so there is no heat transfer. You can read Maxwell with these links p.244 and p.245

  12. Doug Cotton says:


    In response to a question about the article published today (to which I contributed) I will summarise what would happen in a hypothetical Earth with no water and an atmosphere of only nitrogen and oxygen, assumed not to radiate or absorb.

    If this were the case the Earth’s surface would receive more radiation during the day because there would be (virtually) no absorption of incident solar radiation. When you then apply S-B (using integration on a real-world spherical surface) the majority of the radiation would take place directly from the surface at these hotter temperatures.

    But there would still be an adiabatic lapse rate ensuring that the nitrogen and oxygen are much warmer at the base of the atmosphere than at the top, even if no energy flows in and out of the atmosphere. Thus is because an adiabatic lapse rate is just that – adiabatic – and so requires no energy input to maintain the temperature gradient. Thus the surface would not cool anywhere near as much as the Moon’s surface does at night. In fact, the surface temperature would be stabilised by conduction both from the atmosphere and the mass below the surface. There is no reason to believe its mean temperature would be much different, even though its temperature would vary more between day and night.

    In a nutshell, this is why the accusation that radiating gases produce a GHE and raise the mean surface temperature is all garbage.

    You can’t raise or lower the mean surface temperature significantly (within a few thousand years) without transferring an impossible amount of energy into or out of the whole Earth system, including all the mass beneath the crust, right down to the core.  

    That is the core of my argument.  

    See the big picture!

  13. Doug Cotton says:
    November 16, 2012 at 12:39 am
    In Maxwell’s Theory of Heat on pages 244 & 245 he describes how a gas only absorbs radiation when it is cooler than the emitter.

    Where precisely on those two pages does he say that?

  14. Doug Cotton says:

    As I will demonstrate below, the planet Venus provides an interesting example of what would be a major dilemma if one tried to apply the concepts which are used to construct the “standard” radiative greenhouse conjecture.

    You will be aware of how the IPCC and others claim that water vapour, carbon dioxide and other similar radiating gases send backradiation to the surface, and this backradiation supposedly slows the overall rate of cooling of the surface. Somehow, as a result, this is meant to raise the temperature of the surface by 33 degrees. This is the essence of the current description of the “Greenhouse Effect.”

    Does something similar happen on Venus? Many claim that it does.

    However, on Venus the “slowing of the cooling” is supposed to account for about 500 degrees, because that is about how much hotter the surface is than the equivalent radiating temperature of the whole planet.

    But the interesting thing is that, because the atmosphere on Venus is about 94 times the mass of the Earth’s atmosphere, scientists have been able to calculate that only about 2.5% of the Solar radiation at the top of the Venus atmosphere gets through to its surface. That amount would be roughly 10% of the mean radiative flux received at the Earth’s surface.

    Now the radiation received at the Earth’s surface warms it and causes some upwelling radiation, and that in turn leads to downwelling radiation. But obviously the latter could not have more energy than the original radiation reaching the surface.

    Even if the amount of radiation on Earth were able to raise the Earth’s surface by 33 degrees, how could 10% of that radiation raise the Venus temperature by 500 degrees?

    You see, on Earth it is not hard to understand, because we know that the Sun at noon can raise the surface temperature up to and above 288 K, and so we can accept that slowing of the cooling from a temperature higher than 288 K could lead to a mean of 288 K.

    But on Venus, there is no initial boost in temperature (caused by the Sun) that could raise the surface more than 500 degrees using only 10% of the radiative flux we receive on Earth.

    Yet, that is what the temperature is, so how does it get so hot on the Venus surface?

    An explanation, based on empirical results in scientific experiments, will follow in the next day or two when perhaps some readers may have made suggestions as to the mechanism involved.