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Joseph E. Postma and the Greenhouse Effect

Posted on 17 August 2011 by Chris Colose

Some recent attention has recently been going around the web concerning a new “paper” done by Joseph E. Postma (PDF here) which claims to “…physically negate the requirement for a postulation of a radiative atmospheric greenhouse effect.”  It has been echoed particularly by some of the more crackpot web sources like, and of course is spreading around various "skeptic" blogs.

The claims are of course extraordinary, along the lines of Gerlich and Tseuchner’s alleged falsification of the atmospheric greenhouse effectAs is often the case with these types of “skeptics,” the more extravagant the claim, the more obscure the publishing venue; in this case the host is Principia Scientific International, which according to the website “…was conceived after 22 international climate experts and authors joined forces to write the climate science bestseller, ‘Slaying the Sky Dragon: Death of the Greenhouse Gas Theory.’” Most rational people would stop here, but this is the Americanized age where we need to glorify everyone’s opinion and must provide rebuttals for everything, so here it goes:

I ask that the reader have the paper open in a new window so they can follow along with this article.

The Foundations

Most of Postma’s first 6 pages are actually correct.  He describes the greenhouse effect through the so-called layer model, which is a simple way to break up the planet into a “surface” and an “atmosphere,” with outer space overlying the top layer.  This model is described in many climate books such as Dennis Hartmann’s Global Physical Climatology, David Archer’s Understanding the Forecast, Marshall and Plumb’s Atmosphere, Ocean and Climate Dynamics, and radiation books like Grant Petty’s First Course in Atmospheric Radiation.  I will say that I do not particularly like this model as a suitable introduction to the greenhouse effect.  It is useful in many regards, but it fails to capture the physics of the greenhouse effect on account of making a good algebra lesson, and opens itself up to criticism on a number of grounds; that said, if you are going to criticize it, you need to do it right, but also be able to distinguish between understood physics and simple educational tools.

The atmosphere in Postma’s paper is just a single slab, so he has two layers (atmosphere+surface), but in general you can have many atmospheric layers of varying emissivity.  He goes on to solve for the energy balance of each layer (see equations 11-14). RealClimate derived the same result in less than a page here.

 Figure 1: Layer model is Postma's paper.  Click to Enlarge


Postma actually doesn’t get the atmospheric radiative flux right.  The emission is not σTa4, it is fσTa4, where f is the atmospheric emissivity/absorptivity (following his notation).  The emissivity is a unitless factor between 0 and 1 descrbing how good of an absorber/emitter the object is relative to an ideal body.  f = 1 describes a blackbody.  By Kirchoff's law, the absorptivity of a layer must be equal to the emissivity (at the same wavelength),  Both right hand sides of equations 11 and 12 are thus wrong, but it turns out that those errors cancel each other out and he gets equation 14 right.  The factor of 2 in Equation 12 comes about because the atmosphere emits both up and down, although Postma clearly doesn't know how to derive this result formally, based on later statements he makes about this.  Toward the end of page 14 he says this is invalid since the atmosphere radiates in 3-D, not just up and down.  In fact, the quantity σT4 refers not only to the total power output of an object (the rate of energy emission), but it also refers to isotropic (equally intense in all directions) radiation.  The result σT4 is obtained if one assumes that a plane radiates uniformly over a hemisphere (for example, the domed "half sphere" field of vision that a human can see  when you stand outside," with the base of that half-sphere being the surface you sre standing on; the other hemisphere is invisible (see this image).

So far, it is simple textbook stuff with not much promise.

Geometry of the Global Energy Budget

Postma then goes on to describe fictitious “boundary conditions.”  In particular, he seems to have serious objections to the averaging of the solar radiative flux over the Earth.  In essence, he would prefer we had one sun delivering 1370 W/m2 of energy to the planet, with a day side and a night side, noon and twilight, etc. instead of the simple model where we average 1370/4=342.5 W/m2 over the planet (so that the whole Earth is receiving the appropriate "average" solar radiation).  The number becomes ~240 W/m2 when you account for the planetary albedo (or reflectivity). 

The factor of 4 is the ratio of the surface area to the cross section of the planet, and is the shadow cast by a spherical Earth.  It is therefore a geometrical re-distribution factor; it remains “4” if all the starlight is distributed evenly over the sphere; it is “2” if the light is uniformly distributed over the starlit hemisphere alone; with no re-distribution, the denominator would be 1/cosine(zenith angle) for the local solar flux.

In simple textbook models, we like to prefer explanations that get a point across, and then build in complexity from there (see Smith 2008 for descriptions on a rotating Earth).  Of course, students who use this model are probably educated to the point where they know that day and night exist, and certainly GCMs have a diurnal cycle.  The radiative calculations are done explicitly by accounting for the temperature distribution and absorber amount that is encountered at each grid box.  Postma is simply tackling a non-issue, just as how people criticize the term “greenhouse effect” for not working like a glass greenhouse. Postma objects to teaching this simple model because it is not real.   All that is done, however, is to use a brilliant and sophisticated technique, taught only to the geniuses among us, called averaging! And of course, simple models are used in any is how we learn.

But, in actuality, the globally averaged solar re-distribution approximation is not bad when we use it to describe the temperature for planets like Earth or Venus.  These planets have an atmosphere or ocean that transport heat effectively, especially Venus with virtually no day-to-night or pole-to-equator temperature gradient.  The atmosphere and/or ocean help smooth the diurnal temperature difference very well.  Therefore, when coming up with a temperature estimate, it is a great first approximation.  If you want the local equilibrium temperature for an airless body like Mercury or the Moon (that does not transport heat), then you want to use the no-redistribution or hemisphere only solar factor.  This is well-known (see e.g., Selsis et al 2007).  On Mercury, there is no heat distribution and very little thermal inertia; before the sunrise the temperature on the surface is somewhere near 100 K (-173 °C) and by noon the temperature on the surface of Mercury rises to about 700 K (427 °C).  This may also be relevant for tide-locked planets (very slow rotation since one side is always facing the host star, the other in perpetual darkness).  Earth does not experience any such changes of the sort.  On Venus, the variability is even less and most of the planet is at around 735 K. 


To summarize Part 1, Joseph E. Postma did not like a simple model of Earth’s radiative balance where we approximate the Earth as a sphere with uniform solar absorption.  Of course, this is never done in climate modeling or in more detailed analyses appropriate for scholarly literature, so it is more an exercise in complaining about undergraduate education than an attempt to correct what he calls a “paradigm” in climatology.  Nonetheless, the 0-D energy balance model is a useful approximation on Earth when coming up with an average emission temperature (~255 K), since air circulations and oceans tend to even out the diurnal temperature gradient on Earth, in addition to the thermal inertia provided by the system.

In Part 2, I will examine several of the other claims in the paper.

These posts comprise the Advanced rebuttal to Postma disproved the greenhouse effect

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Comments 101 to 150 out of 161:

  1. "give me an example of how it could be misinterpreted"

    It will be misterpreted precisely by avoiding the heat flow equation, and thus thinking that perhaps the cooler object heats the warmer object because the cooler emission "hit" it.  But of course, this is why it is important to reference the heat flow equation.

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  2. It is unfortunate that so much time has to be wasted on BS like this.

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  3. Postma provides a great demonstration of denial here, in particular of the first law of thermodynamics, conservation of energy.

    At equilibrium, which may include averaged short term variations around that equilbrium, the energy leaving a mass (surface, atmosphere, red-faced denier) equals the energy entering that mass (photons, convection, junk food). Input = output, in other words. If there is an imbalance, as with the current climate and radiative imbalance, internal energy will change and with it temperature. 

    The lowest radiative input to a mass, the lowest contribution to that masses temperature, would be the mass surrounded by absolute zero, with the 3K universal background radiation of deep space a close second.

    Any object warmer than absolute zero, regardless of whether it is warmer or cooler than that mass, radiates photons according to its emissivity, and any of those photons absorbed by the mass in question increase it's energy. That added energy makes the mass warmer, until (via radiation, convection, conduction) the increased temperature causes the mass to lose energy at the same rate it gains it. 

    Radiation from anything above absolute zero will warm an object compared to its absence - and the warmer the radiating object the warmer the receiving object will become, no matter what their relative temperatures are. The starting point is zero, and even a relatively cool radiator provides a non-zero addition to nearby masses energies. Cool objects do, indeed, cause nearby warm objects to rise in temperature. 


    Basic physics. Which Postma denies. His arguments are meaningless, Q.E.D. Not surprisingly, even many of the pseudo-skeptics disavow Postma and the 'Slayers', finding their imaginary physics an embarrassment...

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  4. "give me an example of how it could be misinterpreted"

    It can be misinterpreted by inferring that a cold source can heat a warmer source.  Of course, this is why the heat flow equation must be referenced with the answer, so that such misinferrence doesn't arise.

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  5. "It can be misinterpreted by inferring that a cold source can heat a warmer source. "

    O.K., give me an example of how that can be done.

    BTW, the net flow of heat energy is always from the warmer object to the cooler, so it is pretty irrelevant anyway. 

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  6. "It is unfortunate that so much time has to be wasted on BS like this."

    Unfortunate, but also illuminating to watch cognitive dissonance on steroids.

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  7. Mr. Postma, when the photon from the cooler source hits the warmer source (which you acknowledge does happen), does the warmer source gain energy?  Does the photon have any effect on the warmer body? 

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  8. "It can be misinterpreted by inferring that a cold source can heat a warmer source. "

    This essentially explains why JPostma wouldn't give a direct answer to my question, but it isn't the one he thinks it is.  If some proposition X can be used to derive some conclusion Y, then if one accepts X then one must also accept Y, unless they can find an error in the chain of reasoning that links X to Y.  However, the possibility that there may be a specious chain of reasoning that links X to Y is not a good reason to refuse to explicitly state that you accept X if you actually do.  Refusal to do so is basically cowardice, not being confident that you will be able to demonstrate an error in the later chain of reasoning.

    Unfortunately I suspect JPostma knows at some level that if he maes a genuine attempt to engage in the thought experiment, he might not be able to spot a flaw in the chain of reasoning, but is unwilling to accept that his understanding of Y might be incorrect.

    This is why I often try to ask skeptics a series of carefully posed questions that are designed to define their position as clearly and unambiguously as possible, so that if they are right, we can all see if, and if they are wrong, then that will also be obvious.  However in my experience, this is generally met by evasion.  JPostma has provided a particularly clear example of this.

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    Moderator Response:

    [TD] I believe Robert Murphy has asked the next question that Dikran would have asked.  JPostma, please give a simple yes or no answer to that question, and only then give any explanation that you'd like to give.

  9. Of course energy can't flow from a cold source to a warmer source... I mean, that's why when you open a freezer the light from the bulb in the back can't travel from the cold area at the back of the freezer to the warmer area of your eyes. :]

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  10. Energy can't flow from a cold source to a warmer object? But most of the world around me is cooler than my body temperature, and that means Aaaahhh, I'm blind!

    Utter nonsense, Postma, utter nonsense.

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  11. Could anyone give a real life example of cold heating hot, or energy being created from nothing as the K&T energy budgets suggest.

    So, if cold could in fact heat the already hot, then this would have been established as a theory and a universal fact of physics. I would invite someone here to give a real life example!

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  12. Devon, do all things above absolute zero radiate?

    If so, then all such things are both emitting and absorbing radiated energy.  "Cold" things emit less energy than "hot" things, but all things are relative, and all things absorb energy. 

    A block of ice is radiating energy (else you wouldn't be able to see it).  A block of red hot iron is radiating.  Put the two in the same room.  Now put an identical block of red hot iron in an identical room but without the ice.  Which block of iron cools down more rapidly? 

    It's not that the room is heating the iron above its initial temperature.  Rather, it is decreasing the cooling efficiency of the iron relative to the situation with the block of ice. 

    In the same way, the atmosphere is absorbing energy radiated by the surface.  Some of that radiation is then radiated downward, back to the surface.  The surface is not a static energy source (well, the geothermal component is, but it's relatively small).  It is continually (except at night) warmed by the sun.  Energy once emitted by the surface returns to the surface and brings it to a temperature greater than solar energy alone would produce.  Keep in mind that downwelling radiation has been measured from the surface directly for about twenty years.  It's real.  The atmosphere is radiating toward the surface. 

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  13. And again, Devon, the question Postma refused to answer: is the energy being radiated from Object A (at 10C) absorbed by Object B (at 50C)?

    As soon as we start talking about "heat," the discussion gets silly.  The term "heat" needs to be described in terms of energy exchange.  The term "net" needs to be incorporated.  The rhetorical ploy is to try to push the "argument" into terms that the general public understands: "cold things don't warm hot things."  The reality is that all things absorb/emit radiation.  That is, "all things exchange energy."  Thus, cold things do indeed supply energy to warm things, but the warm things get rid of more energy than they absorb.

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  14. The posts by Postma and Devon raise the extraordinary image of a photon looking ahead along its path, measuring the temperature (or perhaps heat content) of the object it would strike, and then deciding retrospectively not to be emitted.


    I can see why Postma might not want to make his views too explicit.

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  15. JPostma @51 writes in response to my post @50:

    "   "sufficient to emit greater energy at source than is recieve         by incident radiation on the device"

    That violates the first law of thermodynamics, and though I've refrained from engaging in the type of ad-hominem attack continually thrown my way, a statement like this really does expose scientific incompetency and a clutching of straws. I do apologize for having to make that remark, but alas, it couldn't be passed over in kindness, this time. Those preeminent experimentalists did not indeed interpret that their apparatus was magically producing more energy than received, ostensibly finding an exception to the 1st Law of thermodynamics. They would have laughed at that. What they found is that they could get sunlight to induce its maximum temperature on a plane, a temperature which is well above +100C. It is not an unexpected result."

    (Initial quote italicized for clarity.)

    I will concede that my thought was poorly expressed so that it could be misunderstood.  Allow me to clarrify.

    The de Saussure hot box consisted of an insulated box painted black in the interior, above which were mounted two or more glass panels to allow in sunlight but trap heat (both convective or radiant):

    It should be noted that the addition of more than one glass panel in no way improves the traping of heat escape by convection.  One panel is sufficient to stop the mixing of the gasses from inside and outside the box, and hence to stop the convective transfer of heat from inside to outside the box.  It does, however, improve the traping of heat both by radiant transfer and by conduction through the glass.  In doing so, it brings the hotbox model closer to a model of the atmospheric greenhouse effect, in that no energy escapes to space by either conduction or convection.

    Using de Saussure hot boxes, de Saussure measured temperatures as high as 383 K, and John Herschel measured temperatures as high as 388.5 K, in the interior most comparment of the device.  The did so in regions where (due to latitude) peak surface insolation was almost certainly less than 1100 W/m^2, and probably less than 1000 W/m^2.  However, the black body radiation for 383 K radiates 1220 W/m^2, while at 388.5 K it radiates 1291.7 W/m^2.  That is, at the "source" (ie, the interior of the innermost compartment of the device), the energy radiated by black body radiation was at least 100 W/m^2 (9%) greater than the "incident radiation on the device" (ie, the solar energy falling on uppermost panel of glass).

    Postma does not like the result, so he disputes the written record (and in de Saussure's case, publicly demonstrated in London and Paris) of two of the foremost experimental scientists of their day as "anecdotal".  Consequently I refer to a recent test of a single panel hot box (solar cooker) in Jordan:

    The "black coated, fixed" cooker is the one most analogous to a de Saussure hot box.  As can be seen, the average peak temperature over three days measurements achieved in the water in the black kettle within the box was 341.4 K.  The equivalent black body radiation was 770.2 W/m^2.  In contrast, the peak insolation recorded on any day during the experiment was was 717.4 W/m^2, and the insolation at the 14th hour (ie, the time of peak temperature) was just 364.5 W/m^2, less than half of the black body energy of the water.  Without water to act as thermal ballast, the interior temperature of the hot box would have peaked earlier and time, and been greater than that recorded.

    The obvious conclusion is that the interior temperatures in de Saussure hot boxes can easily be high enough that the interior black body emission from the inner most compartment exceeds in energy that of the incident sunlight.  Postma says that this is impossible.  Indeed, it is essential to his claims that this is impossible.  It cannot be explained by the prevention of convection, and nor (given the high thermal conductivity of glass) can it be explained by insulation against conduction through the glass.  That means any explanation of the increased temperature must include a greenhouse effect.

    To illustrate this point, consider two hot box designs:

    The first hot box is sealed by a panel that is transparent to both visible and IR light, but impermiable to air.  Because it is impermiable to air, it prevents any mixing of external with internal air, and hence any escape of heat by convection.  Because it is transparent to IR light, it neither absorbs nor radiates IR light.  Therefore any IR radiation leaving the box must come from the floor of the box, as illustrated in (1) above.

    The second hot box is sealed by a panel that is transparent to visible light, but absorbs IR light perfectly (emissivity = 1 for IR).  Because it absorbs all IR radiation that falls on it, any IR radiaton from the floor of the box is absorbed by it.  Because absorptivity equals emissivity, that means that energy is then reradiated, with half of it going up, and half of it going down, back into the box, as illustrated in (2) above.

    Now enter the laws of thermodynamics.  In particular, in this context the first law states that for any horizontal line drawn through a "box" above (horizontal plane for actual 3 D boxes), the energy going up equals the energy going down.  That is, 1U = 1D, 2u = 2D, 2u = 2d, and 2U = 2D + 2d = 2 x 2D.  (Note: 1U is energy flux U for box 1, etc.  It is not 1 x U.)  

    Further, the second law of thermodynamics states that for each such horizontal line, the entropy of the energy going up will not be less than the entropy of the energy going down.  Entropy, however, is the energy divided by the temperature.  The temperature of the light for black body radiation is just the temperature of the black body that emitted it.  Where it combines the light from two distinct black bodies, the entropy will be the energy weighted average of the entropies of the two black bodies.

    So, let's assume that 1D = 2D equals 1100 W/m^2.  Let us also assume the boxes are cubes with dimensions of 1 meter per side.  Then the temperature of the base of box 1 equals 373.2 K (~100 C), and the entropy of 1U = 1100/373.2 = 2.95 J/K.  In constrast, the black body emitting 1D was the Sun, with a surface temperature of approximately 5,750 K.  Consequently the entropy of 1D is 0.2 J/K, and as required the entropy of all downward energy at a given distance above the bottom of the box is less than the entropy of all upward energy at the same distance.  Indeed, the temperature of the bottom of the box would have to reach 5,750 K for that to not be the case - something it cannot do because of the first law of thermodynamics.

    In the second box, the temperature of the panel is also 373.2 K, and hence the entropy of 2u is 2.95 J/K.  The temperature of the base of box 2, however, rises to 443.8 K (~170 C).  The upward power from that base (2U) equals 2200 W/m^2.  The entropy of that energy is, therefore, 4.96 J/K.  That is comfortably greater than that of both 2D and 2d(=2u), and certainly greater than their combined entropy of 1.57 J/K.  Therefore the 2nd law of thermodynamics cannot forbid a situation such as illustrated in box 2, and the first law requires that the temperature of the floor of the box be 1.19 times greater than the temperature of the panel.

    (Postma, and others of similar belief, appear to confuse themselves by using imprecise statements of the 2nd law, to the effect that no body can be gain heat from a cooler body.  Heat, however, is net energy transfer.  In box 2, the floor of the box (443.8 K) gains heat from the Sun (5,750 K).  It then transfers heat to the panel (373.2 K).  There is energy flow from the panel to the floor, but the energy flow from the floor to the panel, so the net energy flow (heat flow) is from the floor to the panel.  This means that the floor is heated by the Sun, not the panel; but the floor is heated more by the Sun than it would be without the panel.  There are no entropy considerations preventing this unless the floor approaches temperatures near to that of the Sun's surface.)

    The important thing to note, however, is that mere prevention of convection cannot heat the floor more than sufficient to have a black body radiation equal in power to the incident radiation.  Neither can prevention of conduction where radiant heat can escape, as in the examples above, conduction is considered to be zero in both boxes.  Adding conduction can cool the floor temperature, but it cannot increase it in either case.  Therefore floor temperatures greater than the black body temperature for the power of incident solar radiation is proof that a greenhouse effect is in operation.  And just such temperatures have been observed historically by de Saussure and John Herschel, and more recently in testing of solar ovens.

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  16. Devon wrote "Could anyone give a real life example of cold heating hot, or energy being created from nothing as the K&T energy budgets suggest."

    The K&T energy budgets do not reuire energy being created from nothing, nor do they involve cold heating hot.  If you think they do, then you are labouring under a misapprehension.  I'd be happy to walk through the physics with you, provided you are willing (unlike JPostma) to give direct answers to direct questions, unambiguously signalling your agreement or otherwise with each step.  Are you willing to do this, yes or no?

    As for a cool object causing a warm object to become warmer, consider a satellite with a thorium reactor providing an internal heat source.  Being in a vacuum, it can only loose heat radiatively and will reach an equilibrium temperature where radiative losses balance the heat generated by the reactor.  Call this equilibrium temperature T.  Now enclose the satellite in a black plastic sphere, that touches the satellite nowhere.  Some of the heat radiated by the satellite will warm the sphere, which will in turn radiate some of it back towards the satellite, which will then warm to a new equilibrium temperature that is higher than T.  This is true, even though the plastic sphere will be cooler than the satellite.

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  17. A small, but important correction to my comment @114.  Where I say, "Where it combines the light from two distinct black bodies, the entropy will be the energy weighted average of the entropies of the two black bodies", the entropies should be summed, rather than the average taken. 

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  18. Dikran, referring back to MA Rodger's original question @52, Postma appears to have interpreted the scenario claiming that, at the time when the furnace was turned of, the temperature of the Furnace was T(F) and that of the iron was T(i), such that T(i) < T(F), then at some later stage the iron will heat the furnace such that the furnace rises to a temperature greater than T(F), which he correctly claims is impossible, but which entirely misses the point.

    Having a look through the exchange, by his post @64, he finely states his response in a way that makes it clear that is what he is denying (ie, that the temperatur of the furnace is ever raised above the point it had at the time of switching of), and clearly acknowledges that the iron will slow down the cooling of the furnace.

    @67, he is clearly evasive when he writes:

    "The question as to "when" the iron starts to radiate was what was precisely set up as the strawman. If you truly require me to answer "when" the iron starts to radiate, it is troublesome. But the answer is obvious, it has been stated, and the answer is specified directly in the heat flow equation here, and also by the simple understanding of heat flow and the ability to attain equilibrium."

    It is clearly not troublesome as to when the iron will begin to radiate, for it always radiates (as does any object warmer than 0 degrees K).  Thus the iron begins to radiate when it first got seperated from the ore.  Postma provides an equivalent answer @70, saying,

    "... it is precisely clear when the iron radiates. It couldn't be any more clear. I am sorry if it is not clear to you. The answer is "as soon as the iron has a temperature"."

    There is a bit more argy bargy, but by his post @88, I think Postma has clearly answered your question.  Specifically, he writes:

    "'A' emits photons in all directions. However, emission from 'A' does not heat a warmer object, as the heat flow equation shows that heating only occurs from hot to cold."

    That of course is correct, because it is the balance of energy transfer that determines the flow of heat, ie, net energy transfer, a point Postma had conceded still earlier.  In the Socratic method, you cannot expect your opposite to simply parrot your terms, and at that point you shoud have IMO moved on to the next point.

    To be honest, I do not think there is anything to be gained by Socratic method with Postma in any event.  He has already demonstrated a willingness to state flatly contradictory views and rely obscurity to cloak himself with a semblence of reason in lieu of the actuality.   Therefore an attempted Socratic method will be a strictly circular excercise.

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  19. As JPostma appears more comfortable with mathematical formulae, would it be worth restating Robert Murphy's question @107 in the manner below. The statement of JPostma @67 strongly suggests that he is happy wiith the final equation derived below. Thus the question is whether he agrees with its derevation as presented here.

    Net energy flow from black body A with temperature TA to black body B with temperature TB = Energy flow from A to B  minus  Energy flow from B to A.

    Energy flow from A to B = XσTA4
    Energy flow from B to A = XσTB4


    X = a system constant.
    σ = Stefan-Boltzmann constant


    Net Energy flow from A to B = Xσ(TA4 - TB4)

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  20. I beleive that J Postma HAS has made a valid point here and more than adequately addressed the question.

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    Moderator Response:

    [JH] Words written in "all caps" constitute shouting and are therefore prohibited by the SkS Comments Policy. Please read the Comments Policy and adhere to it.  

  21. Tom, The misunderstanding that you suggest Postma was labering under is not reasonable as the initial question clearly stated that the iron had equilibriated wuth the furnace prior to the furnace being switched off.

    Time passes and the iron is soaked in the furnace and the furnace is then switched off, now quickly becoming cooler than the hot iron. [emphasis mine]

    I also addressed this possible misunderstanding as soon as there was clear evidence that it might be the problem, i.e. in the very first reply to the post you mention

    you say "somehow" as if to suggest this is an unlikely scenario. It clearly isn't. The iron in the furnace (as we are discussing radiative transfer) is likely to be insulated (if only by a vacuum) from the body of the furnace, so if the body of the furnace is cooled after the iron has equilibriated with it, then of course the iron will cool more slowly.

    Tom writes:

    There is a bit more argy bargy, but by his post @88, I think Postma has clearly answered your question. Specifically, he writes:

    "'A' emits photons in all directions...."

    The problem with this answer is that it does not mention object B and hence is open to equivocation later in a way that the answer "yes" is not.  "YES" is only three characters, so why would Postma go to the extra effort writing 34, if not to be deliberately obstructive?  BTW, if you notice post 88 was quite a long way into the discussion of that very basic question, and I had already lost patience with his continual obfuscation, as demonstrated by my reply.  Giving what you think is an unambiguous answer, after so much obfuscation, in no way excuses JPostma's behaviour, or warrants me continuing the discussion.

    Giving "yes" and "no" answers is also hardly "parroting terms"!

    As to the effectiveness of Socratic methods.  Firstly when your interloqutor is being deliberately obfuscatory (as is the case here e.g. "the lump of iron radiates what is required of it"), it is not at all unreasonable to require that questions be given a "yes" or "no" answer if they are deliberately framed to elicit an answer of that form, and the good reasons for doing so clearly explained.

    Secondly, Socratic method is an excellent method for seeking scientific truth, provided that is what both parties are actually seeking.  Its use here has provided a definite indication that Postma is not seeking scientific truth, which suggests any form of scientific dialogue is likely to prove unfruitful.

    It is a shame that Postma was not willing to engage in a Socratic dialogue, as it would have provided him with the most direct route to proving that I am wrong (should such a route exist, being a scientists myself, I do not deny the existence of such a route a-priori, and actively want to be shown it should it exist).

    JPostma has gone some way in showing that his views are not quite as bizarre as those of some who cite the second law of thermodynamics as an objection to the EGHE, in that he suggested that cooler objects do emit photons that strike warmer ones.  However getting to that point was like getting blood out of a stone, and it left me without the enthusiasm required to get him to clearly state the answer to the next question.  Life is too short, someone either is interested in communicating their scientific ideas and having them scrutinised, or they are not.  JPostma is in the latter category.

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  22. Devon, I supplied the example you requested; I am willing to go through the physics with you, provided you are willing to adopt the "Socratic method" (i.e. being willing to promptly give direct answers to direct questons).

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  23. devon wrote: "I beleive that J Postma HAS made a valid point here and more than adequately addressed the question."

    Yep. That's why the Earth is shrouded in perpetual darkness. After all, photons can't possibly travel from space, which is cold, to the Earth's atmosphere, which is warmer. There is no sunlight. It does not warm the Earth. Can't happen.

    Either that or what you believe to be "a valid point" is instead, obviously wrong.

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  24. I have been assuming that when, for instance, the early morning sun illuminates a distant icy peak, the radiation by which I see it is reflected from its frosted summit - that is absorbed but then re-emitted before it has a chance to boost the thermal content of the ice. Thus in allowing my eye to detect the mountain, it is not in any way resultant from the temperature of the cold mountain top (relative to the temperature inside my eyeball). Contrary to comment @ 110 & @109/123, I therefore do not consider seeing cold objects as adding to the evidence that JPostma (?or devon) is wrong.

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  25. MA Roger, I agree, however wrapping a satellite in multiple layer insulation might be though.

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  26. MA Rodger @124, when light is reflected of an object, it is not absorbed and then rapidly re-emitted.  Rather it is not absorbed at all, merely reflected, and hence contains practically zero information about the temperature of the reflecting object.  Nor has Postma said that no photons will travel from the colder to the warmer object.  Rather, he has said that any photons emitted by the colder object will carry less energy to the warmer object than the photons emitted by the warm object will carry to the cold object.

    He might have said it clearer, but that is what he has said.

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  27. Tom wrote "Rather, he has said that any photons emitted by the colder object will carry less energy to the warmer object than the photons emitted by the warm object will carry to the cold object."

    I think that is a rather charitable interpretation (which is in general what I would recommend) of what he has actually written (but not what I would recommend if the exercise was to clarify exactly what he was saying).  However in that case he would be consistent with modern statistical intepretations of thermodynamics, in which case there is no problem with backradiation warming the surface (relative to the temperature it would assume in the absence of backradiation).  It is a pity that he refused to give direct answers to direct questions (without being obstructive).  If he had, we would already have resolved this by now.  His loss entirely.

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  28. Tom wrote: "Rather, he has said that any photons emitted by the colder object will carry less energy to the warmer object than the photons emitted by the warm object will carry to the cold object."

    I don't think that interpretation of Postma's position is possible/accurate unless you change "less energy" to "no energy". It seems very clear that he doesn't believe a colder object can 'heat' a warmer object at all. Transferring "less energy" per photon would still result in the colder object giving the warmer object a higher temperature than it would have if the colder object were not there at all... which is contrary to Postma's position. As he put it;

    "It can be misinterpreted by inferring that a cold source can heat a warmer source."

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  29. MA Rodger - You're quite correct, reflection is something else entirely.

    As an emissivity/warming test, how about the following. Open your freezer, stand back a meter or two (outside any convection), and hold your hand up towards it. Your hand will feel cool. Turn your hand towards the rest of the room, it will feel somewhat warmer. 

    Nothing has changed with convection/conduction, but the radiated IR from the kitchen, despite the kitchen being cooler than your hand/body, is higher than that from the freezer. An object cooler than your hand has warmed it. 

    Again, the starting point for radiative energy input to an object is zero - any outside object warmer than absolute zero will radiate some energy towards it, increasing the input energy flow, and warming it until outgoing energy matches incoming. Cool objects warm nearby warmer ones relative to there being no object there are all

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  30. Tom Curtis @126.
    To be more exact about reflection of light, the light from the mountain top or wherever is the result of 'defuse' reflection rather than the mirror-like 'specular' reflection. My understanding of defuse reflection is that it is a lot more complex than simply photons bouncing off the various features of a rough surface/subsurface and can involve a photon being absorbed followed very closely by a newly created photon of the same wavelength being emitted. How important/common the various mechanisms of defuse reflection I know not.

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  31. MA Rodger @130, diffuse reflection can come about either due the very irregular surfaces at the scale of the wavelength of the incident light, or through partial reflection of light of crystal (or other discrete) subsurfaces in a translucent object.  Wikipedia illustrates the later process for a quartz like substance:

    "Figure 1 – General mechanism of diffuse reflection by a solid surface (refraction phenomena not represented)"

    The mechanism for diffuse reflection in snow and ice obviously follows the mechanism above.  Water droplets (as in cloud or fog) also follow the mechanism, but only for light rays that strike at a high angle of incidence.  Most photons with a low angle of incidence enter the droplets and are either absorbed in the droplet or reflected coherently by wavelength in the phenomenon which generates rainbows.  The dependence on angle of incidence for the amount of diffuse reflection in droplets is why clouds with smaller droplet size also have higher albedo. 

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  32. CB Dunkerson @128:

    Postma says @ 72:

    "Please familiarize yourself with the heat flow equation Q = sigma*(Tf^4 - Ti^4). Is the answer still not clear? It also answers your latest question. Please let me know if you still require my help with this, and I will try to make it clear. An object radiates power P = A*sigma*T^4 where A is the surface area and T is the temperature. If you have two objects in a simplified geometry then you get the heat flow as the difference between their emissions, with heat flowing only from the warmer to the cooler. I hope this helps."

    (My emphasis)

    I think that is pretty clear.  If the heat flow is the difference between their emissions, and the heat flow depends on the difference in their temperatures {Q = sigma*(Tf^4 - Ti^4)}, than (at least some) emissions from the cooler object must by absorbed by the warmer object.

    He states it almost as clearly @84:

    "We simply apply the heat flow equation using the Stefan-Boltzmann Law. The result is that heat flow is from hotter to cooler, of course. Thus, the cooler object heats up. The cooler one does not heat the warmer one, of course, and the equation for heat flow obviously does not imply this. Equilibrium is given when the respective emissions cancel eachother out, as in Q = sigma*(Tf^4 - Ti^4). Photons are of course emitted and the equation does not say that no photons are emitted from the cooler object, as you have attempted to conjecture. It is the balance of emission which determines equilibrium, not lack of emission."

    Frankly, part of the problem is that we (regular commentors at SkS) have a tendency to use the term "heat" colloquially, such that when a cooler body causes a warmer body to be warmer than it woud have been in the cooler bodies absence, it has "heated" the warmer body.  In that colluquial usage, it is quite appropriate to say that a person was warmed by their blanket.

    However, in the strict scientific usage, the term "heat" as defined as a term in thermodynamics is the net transfer of energy; and the net energy transfer can only go from hotter to colder.

    In fact, that definition of heat is itself just a holdover from the calorific theory of heat, which is retained in science only because of the great usefulness of the equations that use it.  Standard statements of the laws of thermodynamics are, therefore, like Newton's laws of motion.  They belong to a strictly obsolete theory, that is never-the-less more convenient for calculation than the more rigouress theory that has replaced it.  The difference, however, is that they theory (classical thermodynamics) is obsolete not because of experimental refutation (that I know of), but because its ontology is stricty inconsistent with the ontology of quantum mechanics.  That it, there is no such substance as heat; and the nearest ontological equivalent (energy) does not behave as heat is supposed to behave.  Statements about heat therefore become mere abbreviations for more complex statements about energy.

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  33. Tom@132 The fact heat has a tendency to be used somewhat colloquially and that CB Dunkerson and youself had differing interpretations of what JPostma had written is precisely why he would have shown very good sense in answering my question by saying "yes".  That would have been completely unambiguous and understood by all and would have cut through the confusion caused by the colloquial used of terms such as "heat".

    My use of "socratic method" (as you put it) was intended to do one of two things, either to (i) get to the scientific truth in an efficient manner (as I was designing questions in a manner that reduced the search space of hypotheses rapidly and which were easy for JPostma to answer unambiguously), which would be to JPostma's advantage if he was right or (ii) show that JPostma was not interested in explaining his position and having his theories scrutinised and put to the test.  I am saddened that it turned out to be (ii).  I am confident that I could have explained JPostma's error to him had he been more willing to discuss the science in a less obstructive manner.

    We have learned something about JPostma, which is that his scientific position isn't quite as odd as some of those that make the second law of thermodynamics objection to the greenhouse effect, who seem to think that photons somehow know not to be emitted from a cooler body towards a warmer one.  So he has made some progress here, but he could have made so much more by just typing those three letters "y", "e" and "s".

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  34. In trying to identify the position of JPostma, I don't consider we have lost anything with the recent disappearance of his input from this thread.
    I didn't pick up on it initially, but JPostma was so evidently evasive down this thread that, even assuming he never made inadvertent statements, he never in any way made clear his position. Even in his 'published' work, he mostly presents narrative that requires quite some analysis to derive any true meaning, but such an analysis then engenders too much scope for misinterpretation to be entirely sure.

    In the main he thus presents an excellent obfuscation, but at the expense of appearing a total idiot.

    As an example, he linked to one of his 'publications' @17 above that states

    "Whether the radiation is short-wave solar insolation or long-wave atmospheric emission, both are absorbed directly at the solid surface of the ground, aside from that portion lost to albedo. That is, heat is generated by the action of absorbed radiation directly at the surface, within the first few millimeters or so of soil, as radiation obviously does not penetrate any further than this."

    Yet in this quote he is actually presenting an argument for there being no long-wave atmospheric emissions. To add to the confusion, even his conclusion only appears unambiguously in the caption of a figure he presents. His style is to frequently adopt the 'voice' of the position contrary to his own. So in this quote, even the statement that long wave radiation heats the soil could be construed as being what the greenhouse theory is saying, not what JPostma is saying.
    In this 'publication' he only comes unstuck (by demonstrating obvious error) when he runs out of hidy-holes presenting his conclusions. And on every point made, his conclusions are pretty much obviously wrong.
    For instance, in his conclusions he supprts the assertion "Backradiation neither causes active heating, nor slowed cooling, at the surface." with the following (Note that the Johnson reference he describes elsewhere as "The only attempt at a mathematical physics explanation for radiation obeying the laws of thermodynamics that this author is aware of," Johnson being one of the Sky-Dragon Slayers.):-

    "Given Claes Johnson’s description of radiative heat transfer, radiation from a colder ambient radiative environment should slow down the rate of cooling, and we agree with that. What we didn’t agree with was that “slowed cooling” equated to “higher temperature” because that is obviously sophistic logic."

    What or who JPostma is agreeing with (and why he becomes "we" or why he changes tense) is not evident. Johnson says the heat transfer is only a one-way process, not a two-way process which is why Johnson disagrees with back-radiation. JPostma sees it otherwise - the maths of Johnson indicates a slowing in the rate of cooling but the effect is the same. According to his JPostma's conclusion, it is logic that somehow denies the existence of back-radiation. In the text he explains a little further - "there is nothing which is more patently absurd" than back-radiation having "twice the heating power of the sun" (which it does have) when the atmosphere is so so cold and the sun so terribly hot.

    If you enjoy a good laugh and have the patience, there is certainly a large quantity of patent absurdity in the writing of JPostma.

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  35. MA Rodger @134, I find in the document that Postma approvingly quotes Doug Cotton's gloss on Claes Johnson's theory to the effect that:

    "The only (one way) heat transfer between, say, two parallel plates at different temperatures, corresponds to the energy in the radiation represented by the area between the two Planck curves. The Planck curve for the warmer body always envelopes that for the cooler body – i.e., the area under the cooler body's Planck curve is a subset of that for the warmer body. So each body radiates all the frequencies represented by the area under the Planck curve for the cooler body. However, the radiation represented by the area under the cooler body's curve, for both bodies, radiated in each direction, merely resonates in each body and is thus scattered. There is no associated heat transfer. This is how and why the 2nd Law of Thermodynamics works for radiation."


    "When a body receives incident radiation it "detects" those frequencies (and corresponding intensities) which it can itself radiate. This portion of the incident radiation (which will be all the radiation from a cooler body, or just some from a warmer body) resonates. The resonating process is the process whereby it can "detect" the temperature of the source. The resonating process amounts to immediate re-radiation of equivalent frequencies and intensities. There is no conversion of energy to thermal energy. We know this because if there were, some of that new thermal energy would temporarily warm the already warmer target (impossible by 2nd LoT) and that thermal energy could then escape by means other than radiation."

    (My emphasis)

    If this is what he believes (and it certainly appears to be), I was being far to generous in my interpretation of his responses to Dikran Marsupial.  This would mean that while he does believe "...any photons emitted by the colder object will carry less energy to the warmer object than the photons emitted by the warm object will carry to the cold object", he also believe the emissions from the warmer body are at least in part coordinated by the arrival of photons from the cooler body, such that the arrival of such a photon results in the immediate emission of a photon having the same energy (and hence frequency).  That is, the absorption and emission are simultaneious.

    Clearly that is a bizarre view, for arrival of photons of the same energy from a warmer body do not generate corresponding simulatenious emissions.  Therefore, this theory means that inanimate matter must know the temperature at time of emission of all bodies from which it receives radiation, including across billions of light years of space.  It also requires that normal thermal emissions be coordinate presciently to take into account the arrival of photons from cooler bodies (but not warmer) to avoid radiating more than the appropriate thermal radiation.  Finally, the full (and only) justification for this bizarre view amounts to the flat denial of statistical thermodynamics.   In the end, the theory is justified only by the willful ignorance of over 100 years of the physics of thermodynamics.

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  36. The Prescient Photon Theory, much in evidence on the 2nd Law thread.

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  37. I admire you guys' patience for digging so deep in the bizarro physics world of Postma, Johnson and Cotton. I think Tom summarized it best. They are a little like soneone from the 18th century who couldnt' understand relativity and would absolutely want to reconcile the orbit of Mercury with Newtonian Physics. It is rather annoying that, in the process of attempting that, they feel a need to lecture on how they're the ones getting it right and everybody else is getting it wrong.

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  38. Tom Curtis @135.

    The Cotton-quotes presented by JPostma that you emphasis - I saw in them a more innocent interpretation. Seeing them juxtaposed without the intervening lines which talk about 'quota of radiation' perhaps raises a few doubts in my mind. (It's the description of scattering gets me wondering if this is in some way a mashed-up description of the type of defuse reflection I mentioned @130.) But the writing (Cotton & JPostam both) is so bad and the actual words used so much munbo-jumbo, who knows. (The worst bits of Cotton that I see are not actually in your extracts.)

    The first of your emphasised passages I took to be an attempt to explain that the energy flux C to H equals part of the energy flux H to C. So there is no net energy transfer associated with that "cool portion" of the radiation, and I interpreted the 'resonating' and 'scattering' as simply being what heat does within an object.
    The second empasised passage also talking of 'resonating' but does seem to be saying that while no energy is transferred by the photon into the receiving object as heat, the re-emitted photon does contribute to the radation a black body is supposed to radiate. The "detection" and "immediate re-radiation" I took to be 'in a manner of speaking' rather than literally.

    And JPostma's apparent conclusion from this (which he stitches on to an interpretation of Cotton - the join is not well defined) is that the actual existence-or-not of this "cool portion" of the radiation transfer doesn't matter as it doesn't represent a net energy transfer. JPostma seems entirely oblivious to what happens when the "cool portion" increases in size (a is happening with back-radiation). The net energy transfer, the 'hot portion' would then shrink in size. Thus the hot body is saddled with more energy, which in my understanding would make it what is scientifically called 'hotter'. Simples.
    JPostma thinks otherwise and considers this 'hotter' state to be sophistic logic. So, I see the guy is a prize numpty however you read him.

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  39. MA Rodger @134 said:

    "If you enjoy a good laugh and have the patience, there is certainly a large quantity of patent absurdity in the writing of JPostma."

    No kidding... take this, for example:

    "Greenieism is extinction. Any species that was a “greenie” in the past is extinct, and is guaranteed to go extinct."


    "The climate alarmists are instead trying to negate the human mind. Why don’t they realize that even a cursory understanding of their beloved “Gaia” theory would have to indicate that “mother Earth” created human beings on purpose, in order to help replenish the stock of CO2 in the atmosphere which had almost disappeared which would have caused the mass and final extinction? They don’t want to believe in anything good because their true goal is that they want to murder humans, as we will see below; that is what drives them."


    "They negate the mind, they negate evolution, they hate what evolution produces, they hate all living things in fact because all living things radically modify the environment, even the lowliest bacterium. They must hate their own existence. They are a pestilence unto themselves, and they hate themselves for it, along with everyone else."

    This is all from Postma's blog,

    IMO, this view informs the derisiveness and condescending tone he's used in his comments here at SkS (after all, he's talking to pestilent murders of the mind!)

    And it also makes sense that he evades lines of thought that may eventually lead him to different conclusions than his views permit.

    Interestingly, his complaints about others' sophism end up being projections, because he himself has to resort to manipulating a scientific conversation to keep his pre-conceived notions safe.

    What a shame...

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  40. MA Rodger @138, I think the key thing about Cotton's views is the claim that the energy from the cooler object is not turned into thermal energy.  Thermal energy consists of the vibrations, oscillations and non-coordinated motion within the body or gas.  If the radiant energy is not converted into thermal energy, it must be immediately reradiated from the molecule that absorbed it.  Nor can this be a kind of defuse reflection in that such reflection would be in addition to the thermal radiation of the cooler body.

    In interpreting Postma, it is important to note that he endorses this non-thermalization hypothesis in the lead in to the Cotton quote.  He writes:

    "The problem with the materialist objections is that they think of photons as busy little balls of energy which have to deposit their energy as heat into whatever they interact with, whereas a photon is actually a quantum particle that obeys wave  mechanics. They are not tiny little balls of heat that have to do something that you think you would feel with sense perception…there are higher principles governing things."

    He is definitely rejecting, therefore, the notion that there is a transfer of thermal energy from the cooler body to the warmer body by the photons emitted by the former and absorbed by the later.  There is "... a higher principle governing these things", which higher principle turns out to be a mind/number duality so long as, "mind" is understood in terms of "mental idealism" and  number is understood in terms of "mathematical ontological" (I kid you not).

    (As a side note, it turns out that Postma's views on climate are a consequence of a philosophy which appears to be formed by mashing together ill defined concepts and mistaking the outcome as wisdom because of their ill defined nature.  Search for "ontological" in his paper to find the details.)

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  41. One thing I wanted to draw attention to earlier in the discussion, but never got around to, is that Postma appears to believe in the greenhouse effect.  In his post @33, he writes in response to Composer99:

    ""Several of your other comments suggest you are ignorant of, or unwilling to consider, the Stefan-Boltzmann law, from which the average Earth temperature sans atmospheric greenhouse effect is derived."

    Of course, that law is discussed at length in my papers and has even made its appearance here, in worded form. I am sorry if you missed that. Indeed, it sets the effective temperature of the Earth - but this is not to be thought of as appearing at the ground surface, but somewhere in the middle of the atmosphere."

    (Postma's quote of Composer99 italicized.  Emphasis added.)

    This may not be sufficiently clear, but in his 2nd summary statement in the paper I have been previously quoting, he writes:

    "Even as the climate models show, an increase in cloud height causes an increase in temperature at the surface. This is not due to a backradiation GHE but due to the lapse rate of the atmosphere combined with the average surface of equilibrium being risen further off of the surface."

    In fact, that is the exact mechanism of the greenhouse effect.  Greenhouse gases absorbe IR radiation from the ground, and re-emit it at a higher altitude, thus raising into the atmosphere the level which effectively radiates to space the same energy as is absorbed from the Sun.  That in turn sets the surface temperature, for tropospheric and surface temperatures are coupled by the lapse rate.  I have explained this in more detail (and hopefully greater clarity elsewhere).

    Postma may not accept the greenhouse on this effect, claiming he only admits the effects of clouds as raising the "surface of equilibrium".  If so, his theory is incoherent in that clouds are not sufficient to the task.  Specifically, the equilibrium calculation excludes all energy reflected from the Earth, and so the altitude at which it is reflected has no bearing.

    If he accepts that the IR radiation from greenhouse gases also contributes to setting the "surface of equilibrium", he is in the position of actually accepting the greenhouse effect, but rejecting its consequences (and it by name) because of his misunderstandings of a simplified model used only for teaching.

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  42. Postma was the original "we can explain planetary temperature without GHE" maths wasnt he, using lapse rate as an independent variable?

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  43. Tom Curtis @140.

    Just to correct you because 'mathematical ontology' is something with ligitimate philosophical basis.

    It is "ontological mathematics" that JPostma is rabbiting on about in that paper. Until just now, I assumed he didn't understand what ontology means because to suggest that reality actually consists of mathematics (or "absolute logic" in JPostma's preferred description), to sign up to the "In the beginning there was zero" stuff, that belongs in the lunatic asylum. I say 'until just now' because a quick web search confirms JPostma truly doesn't understand what ontlogy means but it also showed he is actually fully signed up to the "In the beginning there was zero" stuff. Scary.

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  44. Just for future reference, in case Postma ever returns:

    1)  JPostma @51 begins with an odd little screed that ends with the claim that:

    "Thus, there are indeed material and factual objections which clearly relegate the back-radiation/trapping hypothesis as defunct, as there are actual factors which already lend to a higher bottom-of-atmosphere temperature."

    Reduced to its essence, this is a claim that there are more than one factor which raise Global Mean Surface Temperatures above what we would expect from insolation alone, and that consequently the atmospheric greenhouse effect cannot also do so.  That, of course, is a complete non-sequitur.  It is equivalent to arguing that because at least five men are carrying a coffin, there cannot be a sixth man carrying it as well.

    It turns out that these other explanations mostly come down to thermal inertia.  Make no mistake, thermal inertia does warm the Earth.  The do so because energy radiated by a black body goes up with the fourth power.  Thus, if you have a globe with a surface temperature of 388 K on on half, and 188 K on the other half, it will radiate 1,285 W/m^2 to space on the warm side, and only 71 W/m^2 on the cold side, for an average of 678 W/m^2.  It will also have an average temperature of 288 K (~15 C).  In constrast, a globe with a surface temperature of 288 K would only radiate 390 W/m^2, or 58% less.  Thus the globe with uneven temperatures radiates far more energy to space than does the one with even temperatures.  It would be warmer for the same energy recieved than the globe with even temperatures.

    The problem for Postma is that the zero energy model calculation of the expected Earth surface temperature assumes an equal temperature over the entire Earth's surface.  That it, it already allows for a greater contribution to the Earth's warming from equal temperatures than actually exists.  Therefore, latent heat cannot explain the 33 C discrepancy it finds between the energy recieved by the Earth, and the global mean surface temperature. 

    2)  Postma repeatedly ridicules the "one D" model as being completely unrealistic.  He however, develops a model of the diurnal temperature cycle, which he describes in the previously linked paper, by saying:

    "However, the mass of a one-square meter column of air is about 10,000kg, and if it has an average temperature of 255K, has a total energy content of about 10000 kg * 255 K * 1006 J/kg/K = 2.56 x 109 J. With a TOA output around 240 W/m2, the column will lose 10.4 MJ of heat overnight, which would correspond to an aggregate temperature reduction of 0.4% or 10 C. As can be seen from real-world data, the ground surface and near-surface-air drop in temperature by about ten-times that amount overnight, which means that most of the cooling of the column actually occurs at the surface, and thus cooling there is actually enhanced relative to the rest of the column, rather than impeded."

    The implicit model for this calculation assumes that the radiation from all levels is 240 W/m^2, that the average temperature of the atmospheric column is 255 K, that the diurnal temperature range is equal across the entire column, and that the heat dump due to the diurnal temperature range is all to space.  He purports this model represents the prediction of the greenhouse effect; and his conclusion from it makes it into his summary points (point 6), and has been mentioned here (although I could not be bothered chasing down in which post).  The key point about this model is that every one of its features is false.  So when Postma rails about the error of using a simple model (albeit solely for teaching), it shoud be born in mind that he also uses simple models.  There are key differences, however.  It can be shown mathematically that the use of a spherical model equivalent to the simple model used to teach by climate scientists generates the same results, and it is only used for teaching.  Further, it can be shown that once corrected for accuracy as in a GCM, the simple models results can be largely reproduced.  Postma's even more eroneous model, however, shares none of these features.   I will show only one of these points, the difference in diurnal temperature range with altitude:

    3)  Finally, it turns out that "ontological mathematics" is the brain child not of Postma, but of "Mike Hockney", whose book, "Why Math Must Replace Science" is described by Postma as "The Best Science in the Universe", going on to say:

    "The God Series of books by Mike Hockney are, truly, the best set of books on philosophy, science, politics, religion, psychology, death, and life, that have ever been produced in the history of man. The latest book by Hockney is the best of them all"

      In its Amazon blurb, we read:

    "It’s time to replace the scientific method with the mathematical method. It’s time to recognize that true reality is intelligible, not sensible; noumenal, not phenomenal; unobservable, not observable; metaphysical, not physical; hidden, not manifest; rationalist, not empiricist; necessary, not contingent. Physics is literally incapable of detecting true reality since true reality is an eternal, indestructible, dimensionless mathematical Singularity, outside space and time. The Singularity is a precisely defined Fourier frequency domain. There’s nothing “woo woo” about it. It's pure math.

    Physicists suffer from a disorder of the mind that causes them to believe that sensible, temporal objects have more reality than eternal, immutable Platonic mathematical objects, and to place more trust in their senses than in their reason, more trust in the scientific method of “evidence” than the mathematical method of eternal proof.

    Never forget that sensory objects are just ideas in the mind. According to quantum physics, objects are just the observable entities produced by the collapse of unreal wavefunctions, and don’t formally exist when they are not being observed. Niels Bohr, in response to Einstein, literally denied that the moon existed when it wasn’t being observed."

    I would say that you could not make this stuff up, but somebody obviously did.

    In lieu of a biography, in Mike Hockney's Amazon biography reads (in part):

    "Pythagorean Illuminism - the religion of the Illuminati - is the world's only Logos, rational religion. Illuminism rejects faith, rejects prophets, rejects holy books, rejects "revelation", and rejects any Creator. Instead, Illuminism is about the necessary, analytic, immutable, a priori, eternal Platonic truths of mathematics. Mathematics alone furnishes the unarguable, definitive answer to existence. That answer, incredibly, revolves around the immortal, indestructible human soul (the "singularity"). The "Big Bang" - a singularity event - was all about soul (all the souls of the universe, in fact)! The soul is none other than the most basic unit of mathematics: the dimensionless, unobservable point. The soul is "nothing", yet it is also infinity - because it comprises positive and negative infinity, which cancel to nothing. The soul is neither being nor non-being. The soul is BECOMING. If you want to know what it's becoming, read The God Series."

    So Hockney consciously positions his "theory" as the religion of the Illuminati, something Postma is aware of and accepts (though when he blogs about it, he calls it "illuminism").

    My point?  Somebody who would accept and promote this complete tripe is so far beyond crazy they can't see the line anymore.  Forget moonlanding conspiracy theorists.  They are sane compared to this stuff.  And yet the "dragon slaying" branch of AGW skepticism show such profound ability to sort the mental wheat from the chaffe that Postma is one of their leading lights.

    Clearly no rational dialogue (socratic or otherwise) is possible with Postma.

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  45. Should point out that ScienceOfDoom has another article just out here dealing with the misunderstandings of Second Law illuminati. 

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  46. Tom Curtis @144.
    Sorry to bash in again. Your point (1) I think misses some heavy nonsense by JPostma (which is also not addressed by the two SkS posts on his 2011 paper).

    One of the big complaints made by JPostma is that it is wrong to use the 1-D model to calculate the -18ºC average temperature for a non-GHG atmosphere. The -18ºC value is too low, he tells us.  Tellingly, he does not himself present a corrected value. And this is no surprise as the -18ºC from the simple 1-D model is not too low as he insists. It is an over-estimation of the average temperature in the model, something that you will always get from averaging forcings when calculating 4th-powered temperatures in such models. But as temperature lags and surface flues will also act to 'average out' temperatures, the value from the 1-D model becomes usefully accurate.
    Still JPostma complains that the -18ºC represents a linear average of a non-linear relationship which is entirely true. But then all he does towards developing a better estimate is to create what could be called an 'immediate' temperature model - the surface temperature T(t, θL) = (FI(t, θL).(1-α)/σ)¼.
    With α=30% as per the -18ºC figure, that gives a maximum T(t0, θ0) = +87.5ºC for noon on the equator. Mucho mucho scorchio !!

    But there JPostma seems to leave it. He presents a 30ºC figure resulting from the "continuous hemispherical input." This is simply the average temperature required to radiate the total global thermal budget from the bright hemisphere. Because of this, with such a bright-side temperature there is no energy leftfor any heat loss during the night, so the night temperature must therefore be -273ºC or, perhaps better, -238ºC if heat from the Earth's core is factored in. From that, the average over the globe would be -104ºC.
    Now because JPostma has averaged over the bright side - the same crime he accused the 1-D model of doing over the whole globe - the 'instantaneous' average temperature will actually be lower still. Indeed, if you calculate one degree 'instantaneous' temperatures for the bright-side to obtain an average (easier than using calculus as these days my calculus is a little rusty), the bright-side average drops to +16.7ºC and the global average down to -111ºC.

    Of course, this is all over JPostma's head. His 2012 paper revises the +30ºC figure. and provides "updates for the integrated average power of Sunlight (vs. the linearly averaged power in [34](ie in the 2011 paper)), and a modification to the cooling profile to reflect the hidden latent heat energy retention; see Figure 18 below." This bullshit provides him with a new higher figure of +49ºC. Now, for other parts of the nonsense JPostma presents in the 2012 paper, he provides the code he used to obtain his results, but not for this result. So how did he do it? How did he get an average temperature for the bright hemisphere which will radiate at least 28% more energy from that bright hemisphere alone, 28% more than the sun provides for the whole globe? I would guess he has but averaged (and thus still practises the crime he accuses others of perpetrating) - averaged the insolation flux for the daytime equator. It may yet be coincidence, but this average yields the same as JPostma's +49ºC. And being an averaged figure, it provides a temperature higher than otherwise. If you calculate the 'instantaneous' temperature in those one degree steps, the average is +38ºC for the bright-side equator and -100ºC for the global equator.

    And what of that coincidence? The words JPostma uses when trying to explain his +49ºC suggests he does indeed equate the equator with the whole hemisphere.

    "What does occur in one second, and in the square meters where sunlight actually impinges, is illumination of a hemisphere with an intensity projection factor that goes as the function of the cosine from the zenith. If you integrate to the average projection factor and combine this with the Stefan-Boltzmann Law and terrestrial albedo, then the real-time instantaneous heat input is constantly +49ºC. At the zenith it has a maximum of +121ºC, constantly, when the albedo is zero." (His stress)

    This JPostma shows yielding a factor of 0.637 which equals 2/π, a most simplistic result recognisable from even schoolboy calculus as ∫(from -π to +π) cos(t) dt / π.

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  47. MA Rodger @146, I could never hope to point out all the crazy errors in Postma's opus.   For example, I missed the craziness in using just two days data from one location to benchmark global values; the coincidence that those two days happen to be in the month with the greatest average diurnal range at that location; that the observations measured "ground temperature" by placing a thermocouple on top of the ground, and ensuring it was in full sunlight;  that the location was temperate and arid, ensuring a high diurnal temperature range relative to global averages; that he neglects to mention that fully one third of the global surface area is in the tropics with minimal seasonal and diurnal temperature range (so the no variation turns out to be a good approximation); that the largest diurnal and seasonal temperature ranges are found in arid areas which also have the lowest surface emissivity for IR (and albedo for SW radiation), thereby minimizing the difference in radiated power at those locations...

    Having said that, I am glad you stepped in and filled one breach, and am happy for others to do the same.

    Just a parting point.  Using an 8 degree K diurnal temperature range (ie, excedig global averages from the graph above), and modern values for the TOA insolation of 1361 W/m^2, incorporating the diurnal temperature range into the zero dimensional energy balance model lowers the predicted global mean surface temperature from 254.582 K to 254.535 K, a difference of just 0.047 K.  As you point out, Postma ignores non-diurnal temperture range alterations in the predicted temperature (which would lower it further).  Therefore his entire schtick is to complain about an effect making a 0.05 K difference in the predicted GMST without the greenhouse effect, and inflating that figure by dodgy "experimental data", ignoring contrary information, and trashing the first law of thermodynamics as too inconvenient.

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  48. A Note on Fourier and the Greenhouse Effect

    Fourier and his friend de Saussure built a device to "trap heat" from light (electromagnetic) energy, and they found that the interior temperature of the device, where heat was supposed to be trapped, didn't rise above the temperature of the heat source. Therefore, heat does not get trapped in such a way as to increase the temperature above that of the source, and therefore there is no radiative greenhouse effect.

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  49. PDF:

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  50. JPostma... Why is it this doesn't seem to be peer reviewed or published material?

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