Thursday, November 6, 2014

Okulaer on "Why atmospheric radiative greenhouse warming is a chimaera"

Quaternary geologist "okulaer" takes on warmist "Science of Doom"/"SoD" in this essay reposted from his blog. In my opinion, Okulaer meets the SoD "challenge," demonstrating "why atmospheric radiative GH warming is a chimaera," due to inappropriate assumptions regarding the Stefan-Boltzmann [SB] law. 

In a nutshell, while physics textbooks always state the radiative heat transfer equation [based on the SB law] between a hot and cold body as: 

P/A = εσ(Th^4 – Tc^4)

where Th = hot body temperature, Tc = cold body temperature, ε= emissivity, σ=SB constant

climatologists assume 

P/A = εσTh^4 - εσTc^4 is also physically correct

While equivalent algebraically, thermodynamics textbooks never state the heat transfer equation in the form εσTh^4 - εσTc^4 used by climatologists, because to do so assumes bidirectional heat transfer independent of the difference in the simultaneously changing temperatures of the two bodies, which is not true in a physical sense, since Th is simultaneously decreasing due to heat transfer to the cold body, which in-turn increases the temperature Tc of the cold body only. 

These are not independent processes as assumed by the incorrect form of the SB heat transfer equation, but rather dependent on the continuously changing difference in temperatures of the hot and cold bodies (Th^4 – Tc^4). As first demonstrated by Clausius, heat flows in one direction only from hot to cold, dependent upon the continuously changing difference in temperatures of the hot and cold bodies [i.e. radiation transfer IS bidirectional, but heat transfer is unidirectional only] i.e. radiative heat transfer = εσ(Thot^4 – Tcold^4) as stated in thermodynamics textbooks, but is not necessarily equal to εσThot^4 - εσTcold^4 in physics. 

This is how the misconcept arises that Thot [e.g. the Earth surface] increases in temperature due to alleged heat transfer from the cold body at temperature Tcold [e.g. GHGs in the atmosphere] to create the greenhouse effect, whereas in reality the temperature of the Thot body decreases due to heat transfer to the Tcold body, causing an increase in temperature of the Tcold body only. 


For those who challenge okulaer's arguments below, please refer to specific quotes being challenged:

Why ‘atmospheric radiative GH warming’ is a chimaera 

by okulaer

Science of Doom (SoD) has apparently issued a challenge of some sort to a commenter going by the name of ‘Bryan’. This is how SoD describes Bryan:
“Bryan needs no introduction on this blog, but if we were to introduce him it would be as the fearless champion of Gerlich and Tscheuschner.”
And the challenge appears to be a return to the ‘Steel Greenhouse’, a setup that is meant to convey in the simplest possible way the basic mechanism behind ‘atmospheric radiative greenhouse warming’ of the surface of the Earth.

The challenge is as follows:
Case A
Spherical body, A, of radius ra, with an emissivity, εa =1. The sphere is in the vacuum of space.
It is internally heated by a mystery power source (let’s say nuclear, but it doesn’t matter), with power input = P.
The sphere radiates into deep space, let’s say the temperature of deep space = 0K to make the maths simpler.
1. What is the equation for the equilibrium surface temperature of the sphere, Ta?
Case B
The condition of case A, but now body A is surrounded by a slightly larger spherical shell, B, which of course is itself now surrounded by deep space at 0K.
B has a radius rb, with an emissivity, εb =1. This shell is highly conductive and very thin.
2a. What is the equation for the new equilibrium surface temperature, Ta’?
2b. What is the equation for the equilibrium temperature, Tb, of shell B?”
What SoD is of course getting at here, the realisation he is seeking to provoke, is that in the end the shell will be the layer radiating to space rather than the surface of the sphere, andsince the shell at radiative equilibrium needs to give off an equal amount of energy to space per unit of time as the sphere/shell system receives from the mystery internal power source of the sphere, then its temperature would have to be pretty much equal to the surface of the sphere before the shell was emplaced – same temp, same radiation flux. In turn forcing the surface of the sphere, with the shell in place, to become warmer so that it can send a larger radiative flux towards the shell (twice as large, as a matter of fact, seeing that the shell seemingly ‘splits’ the absorbed flux from the sphere and emits only half out to space, with the other half going back in towards the sphere):
SphereShell
Figure 1. Black column (l): inner sphere; Gray column (c): 1 cm vacuum between sphere and shell; Light gray column (r): outer vacuum (space).
Ta = 4√(P/4πra2σ) = 4√(P/Aaσ) = 193.6K*
T≈ Ta = Ta’/4√2 = 193.6K (192.6K)*
Ta’ = (4√2)Ta = 230.2K*
At radiative equilibrium,
P/Aa’ – P/Ab ≈ P/Ab or
P/Ab ≈ (P/Aa’)/2.
Therefore Tb4 ≈ Ta’4/2 or
Tb ≈ 4√(Ta’4/2) →
T≈ Ta’/4√2.
*Temps based on one of SoD’s Notes to the challenge: “For anyone who wants to visualize some numbers: ra=1m, P=1000W, rb=1.01m” Other relevant notes are as follows: “The reason for the ‘slightly larger shell’ is to avoid ‘complex’ view factor issues. (…) The reason for the ‘highly conductive’ and ‘thin’ outer shell, B, is to avoid any temperature difference between the inside and the outside surfaces of the shell. That is, we can assume the outside surface is at the same temperature as the inside surface – both at temperature, Tb.”
Through this exercise, SoD is trying, then, to imply that this is also how the surface/atmosphere system on Earth works.

And he would be both right … and very wrong.

There is no question that replacing the vacuum of space with a massive atmosphere will force the mean surface temperature of Earth to rise significantly, because the energy – after the replacement – escaping the surface as heat would be reduced. This is however NOT because there is an extra energy transfer to the surface from the atmosphere. This is a grave misunderstanding. The misinterpretation of reality lying at the very heart of the whole rGHE/AGW hypothesis. No, it is simply because a massive atmosphere – unlike the ‘non-massive’ vacuum of space – is able to warm and thus attain a temperature much higher than 0 K.

Compare the pure Stefan-Boltzmann equation (1) with the general radiative heat transfer equation (2):
(1) P/A = εσT4 
(2) P/A = εσ(Th4 – Tc4)
The pure version portrays an ideal situation where the radiating object ejects its energy into a perfect (0 K) heat sink. There is a maximum/ideal/largest possible temperature difference between object and surroundings. Hence, there is only the temperature of the object radiating to consider.

The composite version (the general radiative heat transfer equation) reflects a situation where there is no longer just an empty void surrounding the radiating object*, but rather surroundings/other objects with an ability to absorb and store energy, and therefore possessing a temperature. In other words, it’s no longer enough to simply consider the temperature of the radiating object itself. One also needs to take into account the temperature of its surroundings. The temperature difference is no longer the largest possible and so the radiative heat escaping the radiating object (P/A, equal to the more familiar Q) is less than the maximum/ideal value.

*Or, more relevant on Earth, surroundings/objects much, much colder than the radiating object.

Note, in both (1) and (2) above, the left-hand side of the equation is the solution, the value we’re looking for, of the actual physical phenomenon being studied. The right-hand side merely shows us how this value is mathematically derived, based on the temperature (and emissivity/absorptivity) of the objects involved in the thermal exchange (heat transfer). The only radiation ever detected within a thermal exchange is always the ‘heat’ (P/A). In (1), the single mathematical term on the right-hand side simply happens to equal the heat on the left-hand side. In (2) there are two opposing terms on the right-hand side and the heat is therefore only the net (the sum) of the two. In this case, each single term on the right-hand side only signifies a potential flow of energy. They would only bereal (detectable, thermodynamically working) flows of energy if they were facing a perfect (0 K) heat sink like in (1), that is, if they were completely thermally isolated from one another.

This is an extremely important point, because people like SoD (and the entire ‘climate establishment’) base their rGHE/AGW argumentation on the idea that these two opposing terms (in (2)) in fact do represent physically real fluxes of energy, each operating separately and distinctly from the other, inside one single radiation field.

It’s an appallingly naive, simplistic and, quite frankly, absurd view on how things work in the real world. But it has still effectively managed to infect the minds of practically every person alive today. The hypothetical construct claiming the reality of an ‘atmospheric radiative greenhouse effect’ (the rGHE) warming the surface of the Earth is simply taken at face value. It is taken for granted as ‘fact’. By all. It is never questioned in the least, there is no critical thinking whatsoever directed at its fundamental premises and tenets.
The idea is that the atmosphere needs the so-called ‘GHGs’ to radiate a (real, working) flux back down to the surface for it to become warmer. Without these radiatively active gases in the atmosphere, there would be no such flux and the surface could not become as warm as it is. (Read the final part of this post to see what they ignore, promoting this idea.)

In the end, it bases itself wholly on a profound misrepresentation of reality.

Look, the observable warming effect of putting a shell around a heated sphere is real. It does not violate the laws of thermodynamics. Of course it doesn’t. It comes specifically as aconsequence of the definitive physical constraints that they define.

What does violate the laws of thermodynamics, however, is the description given by people like SoD of what happens; their proposed explanation of how the effect comes about.
They propose that the effect is a result of more energy coming IN to the central sphere. 

From a cooler place.

Conceptuallyschematically, one can get away with describing the situation like this if we only include two cooling objects at different temperatures, that is, the warmer object is not supplied with energy from a third object. We can get away with it only because the warmer object in this situation will not at any point have its internal energy increase, that is, become warmer in absolute terms as time passes. Such a description, where energy moves along separate ‘highways’ (depicted in diagrams by opposing arrows), is but a highly simplified (and hence instructive on a basic level) way of explaining an integrated process that in reality is very hard to grasp and to visualise, almost mysterious to us macroscopic creatures. It is what we normally see in textbooks on radiative heat transfer. You will, however, never find an example in any of these textbooks where it is even hinted or suggested that energy transferred from a cold to a hot body in a spontaneous thermal exchange (a heat transfer) will be able to directly cause an increase in the hot body’s internal energy and thus make it warmer in absolute terms.

So even in the ‘two bodies cooling’ situation, it cannot be correct to say that it is the energy coming IN from the cooler to the warmer body that makes the warmer body cool more slowly than if it were facing a heat sink at 0 K. The slower cooling rate of the warmer body is rather the result of less energy going OUT from the warmer body to the cooler one. 

Because it’s facing a higher temperature than 0 K.

So why is this an important distinction? More INPUT vs. less OUTPUT. Because, if you were to connect the warmer body to an external heat source, a third body supplying it with a constant input of energy, and then still, like SoD does, insisted that it is the extra energy from the cooler body facing the warmer one that’s making it ‘not as cold as it could be’, then you would end up breaking the Second Law of Thermodynamics.

How?

Because now this same ‘extra’ energy input (from cold to hot) would be the sole cause of the internal energy, and hence the temperature, of the warmer body rising in absolute terms. No longer ‘making it cool more slowly’, but directly ‘heating’ it.

Why?

Very simple. Remember the 1st Law of Thermodynamics for a solid surface: ΔU = Q = Qin – Qout.
Scenario 1: Warm body facing space.
External heat input (Qin from hot reservoir): 2. Heat output (Qout to space): 2. Net heat (Q): 2 – 2 = 0. No change in internal energy: ΔU = 0. Steady-state temperature. Notice here that the heat output from the warm body equals its Stefan-Boltzmann-derived radiant emittance, because the cold reservoir (space) has no temperature: Q = εσT4. 
Scenario 2: Warm body facing cooler body.
External heat input: 2. Potential heat output (radiant emittance) from the warm body up: 2. Potential heat output (radiant emittance) from the cooler body down: 1. Net heat: 2 – 2 + 1 = 1. Imbalance. The internal energy increases: ΔU = 1. As a consequence, the old steady-state temperature can no longer be maintained. It will rise. Until the radiant emittance (the potentialradiative heat) from the warm body has doubled: 2 – 4 + 2 = 0. A new and higher steady-state temperature. The general radiative heat transfer equation: Q = εσ(Thot4 – Tcold4). The heat moving from hot to cold (Q) is now not the same as either of the radiant emittances (potential heats), σT4, of the two opposing bodies.
So what changes from the first to the second scenario above?
  • The external heat input does not change. It is 2 in both scenarios.
  • The initial heat output/radiant emittance from the warm body also doesn’t change. It is 2 in both scenarios.
  • And still the temperature of the warm body rises in absolute terms. Its internal energy increases. Making the energy output from the warm body rise as well, from 2 to 4.
How, in the world of SoD, is this accomplished?

By ADDING extra energy to the warm body, increasing the energy INPUT. The initial 1 coming in from the cooler body. That’s the only difference.

This and ONLY this is what makes the warm body even warmer, raising its temperature from one steady state to a higher one. So the energy ‘flux’ from the cooler to the warm body directly increases the internal energy, and thereby the temperature, of the warm body. As you can see above, there is no help whatsoever from any of the other two fluxes involved.

This is a transfer of HEAT, folks. There is no other word for it. A transfer of energy directly adding to the internal energy and thus raising the temperature of the receiving system, is thermodynamically defined as HEAT (or work). And heat does not move spontaneously from cold to hot. NEVER.

You just cannot describe the process in this way. If the insulated object warms, it’s because the energy from the heat source (like the Sun) can no longer be released as fast from the insulated object as it comes in, so it accumulates. The INPUT remains the same. The OUTPUT, however, is reduced. So the input energy from the heat source (the Sun) piles up. In SoD’s world, it is not the energy coming in from the heat source that piles up and does the warming. It’s rather his extra energy input (actually energy already rejected, coming back a second round to do thermodynamic work a second time) from the cooler atmosphere. Increasing the INPUT which in turn increases the OUTPUT. Reality totally turned on its head.

The energy exchange in a radiative heat transfer is continuous, simultaneous and instantaneous, the radiation field through which the heat is transferred completely integrated and indivisible. Which means there is no way you could ever detect any surface effect of separate emittances, separate waves of radiation (or ‘photons’ if you will) moving around the field. ONLY THE HEAT, the spontaneously occurring vector (net) sum of them all, moving through the field in one direction – from hot to cold – is a real transfer of energy, directly detectable and sensible. It is equivalent to a waterfall, wind or to an electric current, all moving spontaneously from high to low potential.

SoD and the climate establishment need to stop pretending that there are two separate fluxes of energy operating distinct from the other one within one and the same radiation field, one and the same thermal exchange. As if they were both ‘heats’ in their own right.


Everyone seems to agree in the end that it’s all about impeding the outward heat flow from the solar-heated surface. But it’s the atmosphere’s TEMPERATURE that does this. Not the presence of the ‘GHGs’. The temperature gradient away from the surface and up through the troposphere + the weight of the atmosphere, suppressing buoyant uplift and evaporation from the surface, are what determines the degree of impedance. Not ‘back radiation’.


What the proponents of the rGHE/AGW hypothesis (like SoD) consistently fail to take in are two exceedingly basic points that reveal their hypothesized ‘radiative warming effect’ to be a mere figment of their imaginations – a chimaera:
  1. The very presence of a fluid (like water or air) on top of or surrounding a heated surface will make it impossible for that surface to ever achieve a purely radiative equilibrium with its heat source. As long as the fluid is still in place. Because the heated surface and the fluid would be directly and tightly conductively > convectively coupled. Meaning the fluid would naturally and automatically have energy transferred to it from the heated surface via conduction > convection and would hence warm. Concerning our Earth’s surface/atmosphere system, the atmosphere would warm no matter what, as long as the surface is still heated by the Sun. It doesn’t matter if the atmosphere contains radiatively active (IR absorbing/emitting) gases or not. Because the atmosphere does not depend on IR absorption for warming. It contributes, yes, but it is not the sole player. Not even the most important one.*
  2. When the energy is already in the atmosphere, though, brought there by various heat transfers from the surface, it can only escape the total system by being radiated away to space. There is no use bringing it back down to the surface. Meaning,without radiatively active gases present in the atmosphere, it would still warm convectively from the surface, but could not adequately cool radiatively to space. In other words, the radiatively active gases, by people like SoD hilariously called ‘greenhouse gases’ or ‘GHGs’, do not enable the atmosphere towarm. They enable it to cool. The corollary of this? Without them, the Earth would be a much hotter place. Not a colder one. And what compound is the prime (almost exclusive) tropospheric radiative coolant? H2O. Water. In all its glory.**
*According to the Earth energy budget of Stephens et al. 2012, the atmosphere gains its energy by way of heat transfer from three different sources: (a) absorption of incoming (solar) radiation: 75 W/m2(b) absorption of outgoing (terrestrial) radiation: [398-345.6-20=] 32.4 W/m2, and (c) conduction and water vapour condensation: [24+88=] 112 W/m2; all in all [75+32.4+112=] 219.4 W/m2. (Note how the atmospheric absorption of incoming radiative heat (from the Sun) is about 2.3 times as large as the absorption ofoutgoing radiative heat (from the surface). Likewise, how the conductive/latent heat transfer is nearly 3.5 times as large as the radiative heat transfer from the surface to the atmosphere. On a global average.)
**
stratosphere-radiation-by-species-1460
Figure 2. The dotted line approximates the tropopause. H2O effectively does all the tropospheric cooling, from the entire column, but primarily from the upper levels. 

upwelling_brightness1
Figure 3. Fig. 2 confirmed. Lower diagram shows the surface radiation allowed through the atmospheric window, meaning 288K radiation directly from surface to space. Upper diagram shows Earth’s final/total radiative flux to space: surface (atm window) + troposphere. We see that what’s added to the surface radiation is derived from the water bands, from all temperature levels between surface and tropopause.

23 comments:

  1. All alarmist comments are based on IPCC documentation, and that documentation says the Earth's surface would be 33 degrees colder without greenhouse gases. Water vapour is thus meant to be doing most of that warming from about 254.5K to about 287.5K to the nearest half degree.

    But in calculating the 254.5K temperature they fail to alter the albedo which, according to their energy diagrams includes 30% of solar radiation reflected back to space by those clouds which would only exist if the greenhouse pollutant, water vapour actually existed. But they have assumed it doesn't in this scenario. So they incorrectly use only 70% of a quarter of the solar flux (1365W/m^2) and then they also assume incorrectly that emissivity is 1.0000, and so then then incorrectly get that temperature of 254.5K in Stefan-Boltzmann calculations.

    The ramifications of this enormous oversight are huge, because if they had not reduced the radiation by 30% due to the clouds that don't exist. and if they had used a more realistic emissivity for a dry, rocky planet - say 0.88, then they would have got a temperature of 287.58K which is close enough to what is the existing mean temperature with GH gases that are thus doing no warming at all. I would add that the emissivity is more likely to be lower than 0.88, this giving a higher temperature above 290K, and so GH gases are cooling Earth.

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    1. Sorry Doug, you completely lost me at the "clouds that don't exist"

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  2. "...radiation transfer IS bidirectional..."

    That depends upon how one defines "radiation transfer"; if you define it to include not only the emission of radiation at one point but the absorption of that radiation at another point, then radiation transfer is NOT bidirectional. The key is whether thermal radiation from a a cooler region can be absorbed by a warmer region. See my 2010 article, The Greenhouse Effect: Incompetence in Climate Science. I have since tried to make this point (at Claes Johnson's blog, for example) many times, but no one seems to listen to anything but their own inner muse--instead I find you still fruitlessly arguing as Claes did, that the distributive law of elementary algebra does not hold for the S-B formula. I mourn for the general sorry state of physics understanding today (not least because it has kept my simple but seminal contributions from being properly appreciated). And I told you people 4 years ago to have done with Scienceofdoom (just a month before I definitively disproved the greenhouse effect with my Venus/Earth temperatures comparison). Every scientist, at least, should know by now that ALL of the defenders and promulgators of the "consensus" climate science are not just wrong, but incompetent.

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    1. "if you define it to include not only the emission of radiation at one point but the absorption of that radiation at another point, then radiation transfer is NOT bidirectional." Well sure, if you define something differently from convention, then you can make it whatever you want. All bodies above 0K radiate, therefore, radiation is bidirectional.

      I agree with you, however, that radiation from a lower temperature/frequency/energy body is not thermalized by a higher temperature/frequency/energy body.

      Here's a simple example of what I'm talking about in my nutshell above.

      We have a hot blackbody [H] with 10 units of heat energy and a cold blackbody [C] with 5 units of heat energy.

      Lets say the hot body radiates 2 units of radiation to the cold body, and the cold body radiates 1 unit of radiation to the hot body

      H → 2 units radiation → ← 1 unit radiation ← C
      10 units energy..........................................5 units energy

      after radiation transfer, climatologists assume the following will occur

      H → 2 units radiation → ← 1 unit radiation ← C
      11 units energy..........................................7 units energy

      Total 18 units of energy, not 15 we started with. Hey the GHE! Free energy!

      Now lets do the same with the proper form of the heat transfer equation:

      H → 2 units radiation → ← 1 unit radiation ← C
      10 units energy..........................................5 units energy

      which after radiation transfer becomes

      H → 2 units radiation → ← 1 unit radiation ← C
      8 units energy..........................................7 units energy

      Total is still 15 units energy, same as we started with, energy is conserved, 1nd and 2nd laws not violated.

      Delete
    2. Shouldn't your final position be 9 units and 6 units?

      Delete
    3. "Shouldn't your final position be 9 units and 6 units?"

      Only if one assumes radiation from a lower temperature/frequency/energy body can warm a body at a higher temperature/frequency/energy, but it cannot.

      Radiation from a lower temperature/frequency/energy body is not thermalized, i.e. does not increase heat, in the higher temperature/frequency/energy body. All of those lower-energy quantum states in the higher temperature/frequency/energy body are already filled and cannot go higher than their present high-energy quantum state. Sending more low energy quanta cannot raise the high quantum state further.

      Heat is not transferred from cold to hot, even though radiation is transferred from cold to hot, but is not thermalized.

      Therefore, the final position of 8 units energy.............7 units energy is correct because the 1 unit of lower temperature/frequency/energy from the cold body cannot be thermalized in the hot body.

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    4. I'm afraid I'm not convinced, the lower temperature body loses 1 unit and gains 2 so how can the lower temperature body be at 7 and not 6, nothing to do with the state of the hotter body and not covered by your point that heat can't be transferred from cold to hot?

      Delete
    5. "in the higher temperature/frequency/energy body. All of those lower-energy quantum states in the higher temperature/frequency/energy body are already filled and cannot go higher than their present high-energy quantum state. Sending more low energy quanta cannot raise the high quantum state further."

      You can never fill the phonon spectra. Phonons are bosonic particles and can be crowded in any number within the same quantum state. If you get an excess of lower frequency phonons in relation to the Bose-Einstein distribution they will eventually scatter into higher frequency states perturbing the unequilibrated distribution function towards the equilibrated Bose-Einstein distribution.

      You are probably thinking about electronic states. Electrons are fermionic particles and thus can not be fitted in the same quantum state.

      In all solids except metals phonons are the main contributors to all energy transport.

      Delete
  3. With no radiative capability within an atmosphere all energy absorbed by the atmosphere from the surface via conduction provokes convection due to uneven surface heating and all energy taken up in convective ascent has to be returned to the surface in convective descent before it can be radiated to space from the surface. That up and down process is adiabatic and so does not allow heat to be released outside the rising and falling parcels of air.

    If one then introduces GHGs they allow radiation to space from within the atmosphere which reduces the energy going back to the surface in convective descent. On the face of it that should cool the surface.

    However, those same GHGs send as much DWIR back to the surface as UWIR was sent out to space and that DWIR compensates for the reduction of energy returning to the surface in convective decent.

    The convective circulation might change a fraction but surface temperature stays the same.

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  4. Thanks, HS :)

    It's so very obvious how the proponents of the rGHE hypothesis (like the IPCC) totally mix up HEAT and ENERGY (unwittingly or deliberately) and doesn't really get the Laws of Thermodynamics.

    All 'heat' is energy. All 'energy' is not heat.

    http://okulaer.wordpress.com/2014/08/31/how-the-ipcc-turn-calculated-numbers-into-heat/

    http://okulaer.wordpress.com/2014/10/24/the-great-magical-greenhouse-effect-self-amplifying-loop/

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    Replies
    1. Agreed. Very unfortunate that most skeptics also make the very same mistakes.

      Delete
  5. I usually tell friends that the first thing they need to understand about climate is the enthalpy of vaporization. Once they understand that concept, everything else as discussed here falls into place.

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  6. The climate alarmist error can be viewed from different point of view:

    The first is to point, as Max Plank states in his book "the theory of heat radiation" , that radiative energy is always emitted at the expense of other forms of energies. The supposition, made by most climate alarmists, that any surface must unconditionally loose E=sigma.T^4 as if it faced a zero Kelvin environment breaks the principle of conservation of energy.
    Even a black surface facing the interstellar void but where chemical reactions accumulate a part of the incoming energy in chemical form will radiate less than a black body. At the surface of the earth, radiation can emit only what is left by evaporation, convection and photosynthesis.
    As a consequence, there is no radiative equilibrium at the surface of the earth.

    A second, complementary, point of view is to observe that the atmosphere is not a black body but radiates (and absorbs) only in selective frequency bands. As such, its equilibrium temperature is not the temperature of a black body. It is directed by its own radiative properties. The radiative properties of the atmosphere prevent most of the low frequency radiations emitted by the ground to reach the zero Kelvin space, so it has to evacuate the energy it receives by evaporation and convection and by increasing its temperature so it can radiate in frequency bands where the atmosphere is not opaque. The first free emission band correspond to the average temperature of the earth.
    Use this MODTRAN simulator http://climatemodels.uchicago.edu/modtran/, select locality: midlatitude winter, no clouds or rain, altitude 0 km, looking up. You will observe that the absorption is high for low frequencies and drops suddenly above 750 cm-1. This radiative window directs the temperature of the ground.

    Observe too that if the temperature of the ground would increase slightly, its radiation profile would slide more into the radiative window, increasing easily the emission from the ground. No tipping point is to be feared.

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  7. Be prepared, always, to untangle the deliberate and relentless mixing of HEAT and ENERGY. It is the key to AGW fraud.

    15µm IR ENERGY has a corresponding temperature of -80ºC.

    http://www.calctool.org/CALC/phys/p_thermo/wien

    W R Pratt

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    1. Right, the GHE assumes a body at -80C [CO2] transfers heat to a body at -18C [Earth] to increase the temperature to 15C. A huge, impossible reduction of entropy in violation of the 2nd law.

      The ~33K atmospheric greenhouse effect is instead created by atmospheric mass/pressure/gravity/lapse rate

      and the ocean greenhouse effect is created by efficiently "trapping" solar energy in the bulk of the oceans but which is then "trapped" by the reduced ~0.76 to ~0.89 far-IR emissivity of the oceans, which "traps" heat from solar radiation in the oceans.

      Delete
  8. The split formula is the only one that can handle different emissivities, and you could also argue that the outgoing radiation from a body can not depend on other nearby bodies and their temperatures.

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    1. 1. "The split formula is the only one that can handle different emissivities"
      While true, that doesn't make it correct, and leads to the problems demonstrated above.

      "the outgoing radiation from a body can not depend on other nearby bodies and their temperatures"

      I never said radiation radiation from a body depends on other bodies. It doesn't. All bodies above 0K radiate regardless of other bodies. However, heat transfer is one-way only from hot to cold. That is the 2nd law. For heat transfer to be from cold to hot requires an impossible reduction of entropy, violating the 2nd law [assuming no work input].

      Delete
    2. It is in my opinion more or less a discussion of words.
      A stress test of the combined formula could be to let the second body/surface to be reflecting.
      It is only the words "the backradiation heats the Earth" that is a bad way to say that the backradiation just reduces the total outgoing radiation.
      You can in some way compare it with the concept of traveling waves where it is easier to split it in a forward and reflected wave.

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    3. "The split formula is the only one that can handle different emissivities"

      It depends whether you discuss the problem of two black-surfaces for which the emissivity is 1 or the problem of the atmosphere.

      In the first case, le combined formula is convenient. The minus term is some power which, everything accounted, is not lost by the warmer surface.

      In the second case, the atmosphere is not a surface and it has different spectral emissivities for each frequency. The split formula is of no use for it.

      Delete
    4. "It is only the words "the backradiation heats the Earth" that is a bad way to say that the backradiation just reduces the total outgoing radiation."

      "Total outgoing radiation" can only be reduced if that radiation is thermalised. 15µm radiation from CO2 cannot be thermalised by molecules which already have a temperature of more than -80ºC. That means "backradiation" from CO2 causes no heating in the Troposphere. Perhaps a little in the Mesosphere but that cannot effect temperatures at the surface.

      W R Pratt

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    5. "Total outgoing radiation can only be reduced if that radiation is thermalised. 15µm radiation from CO2 cannot be thermalised by molecules which already have a temperature of more than -80ºC"

      Agreed:

      http://hockeyschtick.blogspot.com/2014/11/why-global-warming-is-not-explained-by.html

      Delete
  9. http://stevengoddard.wordpress.com/2014/11/10/one-more-time-2/#comment-454418

    nielszoo says:
    November 10, 2014 at 7:02 pm

    A large part of this is that people keep using S-B math and black body math to deal with low pressure gases and that is flat out wrong. Low pressure gases are line absorbers/emitters and treating them like black bodies overstates their energy properties by several orders of magnitude. They should be dealt with via Gas Law as there is no radiative transfer of energy going on in our atmosphere anywhere below the stratosphere. Water droplets and suspended particulates may be able to emit some radiation but at 1 bar none of the gases in our atmosphere can. If they did, thermal cameras and the FLIR sights our military uses would not work. CO2 and CH4 cannot radiate at these low pressures as they never have the time to drop to ground state and emit before they bump into another molecule and transfer heat via convection. Since the energy level of a photon emitted from one of these gases is so small, the only place they have a chance of emitting radiative energy is Antarctica in the middle of the night in the dead of winter. (Still wouldn’t emit as convection still reigns supreme at 1 bar.)

    The problem is that explaining this scientifically requires quite a bit of math and our wonderful public education system has fixed that little hitch for us… no one learns real math anymore so they believe anything they are told.


    mkelly says:
    November 10, 2014 at 9:11 pm

    Nielszoo I used to operate FLIR (forward looking infrared) in an S3 aircraft. The unit had a cooling unit for the mirrors down to -140 F or so. The heat IR signature is what we saw. Clouds were a disruption. Clouds were a disruption for radar too. The water looked black/cold but the wake of ships were easily seen.

    ReplyDelete
  10. See comments:

    http://stevengoddard.wordpress.com/2014/11/11/greenhouse-effect-is-basic-physics-deal-with-reality/#comment-455390

    http://stevengoddard.wordpress.com/2014/11/11/greenhouse-effect-is-basic-physics-deal-with-reality/#comment-455399

    http://stevengoddard.wordpress.com/2014/11/11/greenhouse-effect-is-basic-physics-deal-with-reality/#comment-455423

    nielszoo says:
    November 11, 2014 at 11:51 pm
    Absolutely. Gas Law and gravity decide what the temperature will be depending on solar input. Gases have extremely small emissivity values to begin with and CO2s is something like 0.002 which is, for all practical purposes zero. Of course the IPCC uses a value of 1.0 and treats CO2 like a perfect black body radiating into a 0°K body. Utter fiction.

    http://stevengoddard.wordpress.com/2014/11/11/greenhouse-effect-is-basic-physics-deal-with-reality/#comment-455483

    ReplyDelete