The “Heat” issue once again …

I want to applaud Joseph Postma and his latest blog post, spelling out his grievances against the “Greenhouse Apologists” and how they consistently manage to worm their way out of ever providing a definitive, coherent clarification of how the hypothetical “Radiative Greenhouse Effect” (RGHE, rGHE) is actually meant to work physically, brushing all sceptical objections to their vague – as it seems, deliberately equivocal – contentions aside by simply claiming that our differences are purely of a semantic nature. It doesn’t matter to them whether we describe one and the same process as “reducing cooling” or “increasing warming/heating”, because the end result – a higher temperature – will allegedly be the same either way, ignoring the simple fact that, in reality, these are two fully distinct (as in ‘opposite’) thermodynamic processes: 1) INSULATION, 2) HEATING. And so, conflating them, as if they were somehow basically the same process, causes confusion.

Unnecessary confusion. Scientifically pointless confusion.

Postma puts it very neatly and succinctly:

From Schroeder in “Thermal Physics”:

“Much of thermodynamics deals with three closely related concepts: temperatureenergy, and heat.  Much of students’ difficulty with thermodynamics comes from confusing these three concepts with each other.”

So right at the introductory level we have people on all sides who can neither define nor […] understand what energy, heat, and temperature actually are. I won’t define them for you right now but at least you have the textbook quote to cite that they are indeed not at all the same thing! This confusion about thermodynamic things is par for the course of climate alarmism, its bread and butter.

And:

We’re discussing nature and the way its physics works, and it seems to me that nature doesn’t behave half one way plus another, but quite precisely according to physics and hence mathematics. There is nothing more precise than the behaviour of nature and mathematics and therefore there is nothing more important than their semantics. So, “purely arguing about semantics” is precisely what we’re supposed to do with physics, because this is what gives us understanding of anything about it in the first place.

In short: If we don’t go by the correct, agreed-upon term or definition for any specific physical phenomenon or process that we want to describe and explain, then this will ultimately prevent us from understanding what that physical phenomenon really is and how that physical process really works. We will end up confusing ourselves and/or the people we’re trying to communicate with.

What we say and write about things affects the way we THINK about them.

Most people actually walk around thinking the atmosphere directly warms/heats the surface, in the exact same way the Sun does. That the solar input can only warm it up to a point, and that the atmospheric input is specifically needed to warm it the final stretch, beyond the solar reach, so to say, up to the average temperature as observed. They simply do not get the fundamental distinction between how the Sun works and how the atmosphere works.

And this is simply because no one seems to bother making this distinction clear to them. Rather the opposite appears to be the case …

“Atmospheric back radiation” (LWdown) is consistently described by climate science as if it were an extra separate input of heat to the surface, right next to – and in addition to – the solar input. Everyone should know that it’s not. But climate science and the “Greenhouse Apologists” allow – no, they actively encourage – this profound confusion to prevail. Why? Does it simply come down to intellectual laziness, or is promoting and perpetuating such an endemic state of confusion a necessary thing, a ploy to prevent regular people from asking the wrong kinds of questions? This edifice is, after all, built entirely on pseudoscientific lines of argument …

A recent and apt example of the inanity of the “Greenhouse Apologists” and their absolute obsession with the confused idea of “sky radiation” somehow constituting extra heat to the ground, even without it actually being “heat” (we’re fine, because we don’t CALL it “heat” [Q], we just call it “energy” [E], thus avoiding any potential problems with the 2nd Law of Thermodynamics (which, after all, deals with “heat”, not “energy”), even though we expect our “energy flux” to produce a thermal effect exactly as if it were an actual “heat flux”, as per the 1st Law), is this gem from the well-known “Greenhouse Apologist” ‘The Science of Doom’ (SoD):

Basics Digression

Picture the atmosphere over a long period of time (like a decade), and for the whole globe. If it hasn’t heated up or cooled down we know that the energy in must equal energy out (or if it has only done so only marginally then energy in is almost equal to energy out). This is the first law of thermodynamics – energy is conserved.

What energy comes into the atmosphere?

  1. Solar radiation is partly absorbed by the atmosphere (most is transmitted through and heats the surface of the earth)
  2. Radiation emitted from the earth’s surface (we’ll call this terrestrial radiation) is mostly absorbed by the atmosphere (some is transmitted straight through to space)
  3. Warm air is convected up from the surface
  4. Heat stored in evaporated water vapor (latent heat) is convected up from the surface and the water vapor condenses out, releasing heat into the atmosphere when this happens

How does the atmosphere lose energy?

  1. It radiates downwards to the surface
  2. It radiates out to space

..end of digression

(My boldface.)

This is simply too stupid to be real. And yet he still said it. And I’m sure he meant it. I’ll bet he can’t see the problem himself. SoD is clearly one of those confused specimens incapable of distinguishing between “energy” [E] and “heat” [Q]. He thinks he knows the distinction, oh, yes he does, he’s been telling us for a long time. But he really doesn’t. And here he – once again – shows us just how he doesn’t …

Thermodynamics 101: The atmosphere does not lose energy by radiating downwards to the surface. This would only happen if the surface were colder than the atmosphere. Or in a hypothetical situation where the surface is warmer, but still somehow doesn’t radiate to the atmosphere at the same time as the atmosphere radiates to it.

The atmosphere – on average – only loses energy by radiating to SPACE. It cannot lose energy in any other direction. Because all regions surrounding the atmosphere other than space are – on average – at a higher temperature than the atmosphere. And so the atmosphere will always only gain energy from its thermal interaction with these other regions.

A loss of energy from a thermodynamic system is when, between t0 and t1, its U has decreased, normally associated with an absolute drop in the system’s temperature T (never with a rise). Likewise, a gain of energy to a thermodynamic system is when, between t0 and t1, its U has increased, normally associated with an absolute rise in the system’s temperature T (never with a drop). Yes, that system can indeed lose and gain energy at the same time, and there will be a net loss or a net gain of (internal) energy [U] and a corresponding drop or fall in temperature [T] as a result. But such a simultaneous loss and gain of energy from/to a thermodynamic system resulting in a net change in its U (and T) are – by thermodynamic definition – never part of the same heat transfer. The system can only lose OR gain energy inside ONE specific thermal interaction.

Case in point: The surface of the Earth takes part in TWO heat transfers at the same time: 1) Sun → Sfc, and 2) Sfc → Atm/Space. It always gains energy from the first transfer (its Qin (heat input)), just as it always loses energy through the second (its Qout (heat output)). There is never any gain in energy for the surface, no rise in its U (and thus no rise in its T), resulting from the second transfer specifically, from the average thermal interaction between the surface and the atmosphere/space. The Sun is its “hot reservoir” (heat source) and the atmosphere/space are its “cold reservoir” (heat sink).

Net heat [Qnet] is simply Qin minus Qout. For the Earth, the net heat is close to zero. That is not to say that the heat input from the Sun or the heat output from the Earth are themselves anywhere close to zero. It simply means that they are more or less inversely equal. They balance …

You cannot and should not describe the physical process of “insulation” as an equivalent to – and in terms of – the physical process of “heating”. And so you can’t treat the “atmospheric back radiation” as an ADDITION of energy to the surface, as a separate input equal to the solar one. That would simply be un-physical. You have to treat it only as a reduction of the OUTGOING energy flux, of the surface heat loss:


Figure 1. The surface radiative budget does NOT look like this: IN, 188+345 = +533 W/m2; OUT, -23+(-398) = -421 W/m2. Only “Climate Science” would propose such ridiculousness. It looks rather like this: IN, 188–23 = +165 W/m2; OUT, 345–398 = -53 W/m2. The +165 W/m2 is the Sfc Qin(sw), the -53 W/m2 is the Sfc Qout(lw), the Sfc Qnet(rad) = 165–53 = +112 W/m2. Two separate heat transfers.

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12 comments on “The “Heat” issue once again …

      • okulaer says:

        The saddest thing about this whole thing is that this is far from new knowledge. It’s been known for a long time.

        The way the “Greenhousers” try to get around the obvious problem with the observed non-effect of CO2 on regular heat transfer through a shallow layer of gaseous medium is by saying that it’s all to do with depth; the depth of the air layer in question. The thicker the layer of air, the deeper the air column containing CO2, the more evident becomes the thermal effect (from IR absorbance → heat transfer impedance). It accumulates. It accrues. From basically nothing to something to much. The overall effect from the surface to the top of the atmosphere (an air depth of 10-20 km) is therefore allegedly quite significant indeed. This is all straight from the Beer-Lambert Law, which says that “The absorbance of light through an absorbing medium is directly proportional to the length of the light path (l) through the medium, which is equal to the width of the cuvette holding it.”

        But is this relationship (IR absorbance + great light path length (l) → significant heat transfer impedance (→ warming)) really valid also in our atmosphere? THAT is the big question.

        And it turns out that there is no real reason to assume this to be the case.

        In fact, from consistent empirical observations, whenever you increase the thickness of an air layer beyond some threshold, all you do is reduce any radiative effects on heat transfer (thus, indirectly, on surface temperatures), pretty soon to naught, by letting convection become operative.

        Quotes from the following study (Reilly et al., Lawrence Berkeley Laboratory, 1989):
        http://gaia.lbl.gov/btech/papers/29389.pdf

        “For larger vertical gap widths, where energy savings from the use of infrared absorbing gasses may begin to accrue, convection effects will begin to take effect and negate the positive impact of going to larger gap widths.”

        “In fact, air outperforms SF6 [a much stronger IR absorber than CO2] at gapwidths greater than 9 mm in a vertical window and the benefits from infrared absorption by SF6 have been negated by the magnitude of the convection.”

        Not ‘reduced somewhat’. This is not merely a ‘negative feedback’. It’s NEGATED.

        Beyond the convective threshold, convection controls all heat transfer up through the air column.

        • gbaikie says:

          It seems to me that Atmosphere absorbs little radiant heat, but when the sunlight travels thru more atmosphere one get an addition absorbing little radiant heat. Or a little amount is absorbed when sun is directly over head, but when sun is lower one get significant increase in amount absorbed by atmosphere
          Or in terms of regions, tropics which has sunlight closer to zenith, atmosphere absorbs less, and regions closer to poles where sunlight has to go thru more atmosphere [most of time further from zenith], the atmosphere absorbs more of the sunlight.
          And of course atmosphere includes any clouds.
          And in terms IR emitted from surface, most of IR is going thru more atmosphere- doesn’t matter where [tropics or pole ward].
          Though in all cases I don’t think atmospheric gases absorbs much radiant energy of any kind and atmosphere is more significant in terms scattering/diffusing/reflecting light rather than absorbing it.

    • okulaer says:

      I fear RWturner is all wrong.

      As I’ve pointed out on numerous occasions, both here on this blog and other places, what violates the 2nd Law isn’t the idea that the atmosphere insulates the solar-heated surface of the Earth per se. Our massive atmosphere does insulate the solar-heated surface. And the simple physical phenomenon of “insulation” doesn’t violate the 2nd Law of Thermodynamics in any way.

      What violates the 2nd Law is only the common “back radiation” EXPLANATION of Earth’s elevated Ts, because in this explanation the two hemifluxes conceptually and mathematically making up the net radiation exchange (LWnet(sfc), Qlw(sfc)) between the warm surface and the cool atmosphere/cold space above are specifically separated and put on opposite sides of the surface heat budget (Qin = Qout), AS IF the one (the atmospheric “back radiation” hemiflux, LWdown(sfc)) were an extra, distinct macroscopic INPUT of energy to the surface, right next and completely equivalent to the solar HEAT flux, to make a much larger total macroscopic input flux, while the other (the surface “blackbody radiation” hemiflux, LWup(sfc)) were simply the resultant macroscopic LOSS of energy from the surface, right next and completely equivalent to the conductive and evaporative HEAT fluxes, to make a much larger total macroscopic output flux:

      As long as you’re aware of the fact that neither of the two hemifluxes are themselves HEAT fluxes, that they only make up a heat flux between them, and that this heat flux specifically constitutes the radiative heat LOSS of the surface, then you’ll naturally understand how they must ALWAYS, in any thermodynamic analysis, stick tightly together, kept within the same bracket, both on the LOSS side of the surface budget. And as long as you do it like this, then you’ll be perfectly fine – no 2nd Law violation.

      Split them apart, however, and treat them as if they were individual, independent thermodynamic quantities, placing each of them right beside actual HEAT fluxes, and expecting them to produce the exact same kind of macroscopic (thermodynamic) net effect as these do, then you’ll end up confused and in trouble. The Laws of Thermodynamics simply do not allow such an operation, which MATHEMATICALLY seems perfectly reasonable, but which is in strict violation of fundamental physical principles.

      Here’s an analogy I’ve been using in this regard:

      Imagine you have your hand stretched out with the open palm facing up. In your palm lie two dimes/pennies. A person is standing right in front of your outstretched hand, holding a single dime. In this situation, you represent the surface, the person in front of you represents the atmosphere, and the dimes represent photons.

      Now here’s what happens: The person holding the single dime places it in your palm with his one hand at the very same moment as he grabs the two dimes that were there already with the other, removing them from your hand. That is, he performs these two separate operations simultaneously.

      The question then becomes: Did you ever have THREE dimes in your hand during this exchange?

      The answer is of course “No”. First you had TWO. Then you had ONE. And that’s it. The first of the original two was simply exchanged with another one, while the second was lost.

      People, however, have this instinctive, almost monomaniacal tendency – I would almost call it ‘urge’ – to look at and interpret ONE of these operations (‘events’) at a time, and to just adamantly stick to that approach, an approach that is fundamentally mathematical rather than physical in both origin and application. It basically derives from how our human mind works. It always seeks order and simplicity even when and where there is none to be found. And it does so for a very simple reason: To get a grasp of how things really work. You need to pick the clock apart in order to understand what makes it tick. That is, start by breaking things down into their most basic, irreducible constituents and then work your way up from there. And this has of course turned out to be an exceedingly successful method for gaining knowledge. It has served us well. And still does. However, it CAN also be misapplied. We should be careful not to follow it blindly. Sometimes our mental compartmentalisation process goes too far. We end up “seeing” things (and/or potential connections between things) that aren’t really … real; or meaningful, or relevant to what we’re actually trying to get a grasp of. And so we end up confusing ourselves instead. Mostly regarding “cause and effect”.

      In this case, conflating specific phenomena of the MICRO and MACRO realms is the pitfall to beware. Invoking a distinctly QUANTUM MECHANICAL quantity and/or process to justify or explain an inherently THERMODYNAMIC effect is simply profoundly misunderstood … And people just don’t seem to get exactly HOW misunderstood it really is.

      What most people do is simply analysing the effect of each operation (‘event’) in the analogy above IN ISOLATION from the other one, in fact from everything else. They estimate its effect AS IF the other (opposing) one didn’t happen at the exact same time. They only regard the photon absorption and “forget” or “ignore” the simultaneous (and larger) photon emission. Such a narrow scope doesn’t work if you want to discuss THERMODYNAMIC effects. Then you will only fool yourself into thinking that we’re dealing with two SEPARATE thermodynamic processes in one. We’re not. There aren’t. There is just the one. The one instantaneous exchange.

      There are two distinct ways of seeing this exchange, two ‘perspectives’, so to say:

      #1 The MICROscopic (quantum mechanical) perspective, and
      #2 the MACROscopic (thermodynamical) perspective.

      Both are in a sense ‘real’, but they address very different aspects of ‘reality’.

      What people tend to do is mix them up, or rather somehow merge them into one and the same perspective. And that’s where the confusion arises.

      It is claimed (or at least very much implied) that the atmosphere (the person originally holding the single dime) ADDS energy to the surface (the palm of your outstreched hand). However, this is only correct in the MICROscopic perspective, that is, IF – and only if – we choose to follow ONE particular photon (dime) through the exchange and ignore the other two; that is, the photon/dime originally held by the person in front of you, coming IN from ‘the atmosphere’.

      THAT individual photon (and the energy it carries) is indeed ADDED to the surface in this exchange. But as I pointed out above, this circumstance isn’t “meaningful, or relevant to what we’re actually trying to get a grasp of”. Which is whether or not ‘energy’ (in the generic sense, not one particular quantum of energy) was added from the atmosphere to the surface during the exchange. The MACROscopic perspective.

      What they do is “Invoking a distinctly QUANTUM MECHANICAL quantity and/or process to justify or explain an inherently THERMODYNAMIC (thermal) effect”.

      Did the atmosphere ADD energy equivalent to the energy of a single photon to the surface during the exchange? No. It added one PARTICULAR photon, yes, but it removed two OTHER photons at the exact same time. From the very same surface. Your hand.

      So what ACTUALLY happened? The energy associated with one of the two photons/dimes that you held in your hand originally was simply EXCHANGED with the energy associated with the one photon/dime originally held by the ‘atmosphere’ person in front of you. The other one was lost (removed by the ‘atmosphere’ person), without compensation.

      And so, the NET effect – the THERMODYNAMIC (macroscopic) effect – of the thermal radiative exchange between sfc and atm is that the atmosphere doesn’t add ANY energy at all to the surface (zero dimes), while the surface gives IT some energy (one dime), but LESS energy than it would’ve handed to space in the same situation (two dimes).

  1. Erik says:

    “Insulation” is still the consequence of back-radiation though?

  2. MoS2 says:

    The macroscopic, thermal effect as you call it, is not fundamental.

    The non-fundamental nature is understood by noting that entropy can not be defined when a system is far from equilibrium. Hence, temperature can not be defined since the definition of temperature is directly linked to the response in entropy with change of internal energy (The definition is nicely introduced in Schroeders elementary textbook that you mention).

    Radiative energy transfer between bodies at close proximity is one instance where the equilibrium description breaks down completely. It is necessary to use a full quantum mechanical description in such a case. Since photons are bosons it is also necessary to describe them as a quantum field, not as isolated particles that you can count (different observers disagree on the number of photons in a process).

    A quantum mechanical description is always valid, in principle, although not usually practical when an effective model can be used instead (thermodynamics).

  3. MoS2 says:

    To continue.

    Thermodynamics is the study of systems in equilibrium. Some situations where the systems are out of equilibrium can still be treated with thermodynamics. But a more complete picture is given within transport theory which is considered to be an advanced topic. Daniel Schroeders book on thermal physics has a short section touching upon this, even though the main focus of that textbook is on thermodynamics.

    None the less. Thermodynamics is not the best suited theory to treat radiative energy transfer.

  4. MoS2 says:

    One thing that caught my eye was the idea that insulation is a thermodynamic process.

    First of all, shouldn’t insulation be called a material or matter property, not a process. A process indicates transformation. Insulation just indicates resistance to energy transfer, that is the inverse to thermal conductivity which is the material parameter in Fourier’s law.

    Secondly, this property, insulation, is more related to kinetics than thermodynamics, in the case of energy transport through gasses.

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