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William Kininmonth on the Radiation of Energy and Global Warming

Could ‘the greenhouse effect’ be one of those things that everybody claims to understand because it is apparently so important, but in reality it is not supported by a credible scientific literature?

That’s the view of Bill Kininmonth, meteorologist and head of Australia’s National Climate Centre from 1986 to 1998.

Furthermore, Mr Kininmonth is of the view that, “the role of greenhouse gases is to cool the atmosphere and this, with the surface warming from solar radiation, generates convective instability. It is the temperature lapse rate required for deep convection that leads to the ‘greenhouse effect’”

Confused?

Well in the following note, Mr Kininmonth explains in more detail:

The closest you will come to an explanation of carbon dioxide and the green house effect is in the ‘Frequently Asked Questions’ of the on-line IPCC Fourth Assessment Report.

My critique on them follows.

“The IPCC’s most recent assessment attempts to be helpful to the casual enquirer by having a series of explanations for ‘frequently asked questions’, or FAQs. The first FAQ is ‘What factors determine earth’s climate’? We are informed that, on average, the earth emits 240 w m-2 of radiation to space and that this equates to an emission temperature of -19oC. The earth’s temperature, however, is about 14oC and the -19oC temperature is found at a height of about 5 km above the surface. To quote the IPCC: “The reason the earth’s surface is this warm is the presence of greenhouse gases, which act as a partial blanket for the longwave radiation coming from the earth’s surface. This blanketing is known as the natural greenhouse effect”.

This explanation by the IPCC is clearly misleading, if not wrong. The inference that the greenhouse gases are acting like a blanket suggests that they are increasing the insulating properties of the atmosphere. However, the main gases of the atmosphere are oxygen and nitrogen, non-greenhouse gases, and they are also excellent insulators against the conduction of heat (like a blanket); adding additional trace amounts of carbon dioxide will have no appreciable impact on the insulating properties of the atmosphere.

In its third FAQ, ‘What is the greenhouse effect?’ the IPCC comes to the nub of the issue but provides a different and equally misleading explanation. “Much of the thermal radiation emitted by the land and the ocean is absorbed by the atmosphere, including clouds, and reradiated back to earth. This is called the greenhouse effect”. According to the IPCC’s global energy budget, the surface emits 390 W m-2 of radiation and the energy radiated back to the surface is 324 W m-2. It is difficult to see how an ongoing net loss of longwave radiation energy from the surface of 66 W m-2 can lead to warming! Indeed, we are all aware that between dusk and dawn the earth’s surface cools.

The IPCC has not explained in a scientifically sound and coherent way, how the ‘greenhouse effect’ is maintained. The greenhouse gases do not increase the insulating properties of the atmosphere and the back radiation does not warm the surface. The IPCC explanation of the greenhouse effect is obfuscation and, even to the mildly scientific literate, reflects ignorance of basic processes of the climate system.”

I am of the view that ‘the greenhouse effect’ is one of those things that is accepted because it is there, everybody claims to understand it because it is so important, but in reality few know how it comes about. My explanation follows (and you will not find this in IPCC publications):

“A credible explanation has no need for smoke and mirrors. The energy flow through the climate system is predominantly by way of four stages: 1) absorption of solar radiation at the surface; 2) conduction of heat and evaporation of latent energy from the surface to the atmospheric boundary layer; 3) convective overturning that distributes heat and latent energy through the troposphere; and 4) radiation of energy from the atmosphere to space. We will see that it is the characteristics of convective overturning that keep the surface warmer than it would otherwise be.

The Kiehl and Trenberth (1997) global average energy budget of the earth (see figure, where the units are W m-2) is used by the IPCC and is a useful starting point for explanation of the establishment and maintenance of the greenhouse effect.

Radiation BalanceIPCC.jpg

Of the 340 units of solar radiation entering the earth’s atmosphere, 67 are absorbed by the atmosphere and 168 are absorbed at the surface. There is thus an ongoing source of solar energy available to the atmosphere and the surface.

At the surface there is a net accumulation of radiation energy because the incoming solar radiation (168 units) exceeds the net loss of longwave radiation (66 units).

In the atmospheric layer there is absorption of 417 units (390 of emission from the surface, less 40 that go directly to space, plus absorption of 67 of solar radiation) and an emission of 519 units (324 back to the surface and 195 direct emission to space). The net effect of the interaction between the greenhouse gases and radiation is a tendency to cool the atmosphere because it is continually losing energy.

Overall there is a dichotomy, with radiation processes firstly tending to warm the earth’s surface and secondly tending to cool the atmosphere. Air is an excellent insulator against conduction of heat and will not transfer heat through the atmosphere, as is necessary for energy balance. Also, the thermodynamic properties of air (potential temperature increases with height) ensure that turbulent motions of the atmosphere will mix energy downward, not upward as required.

The process for transferring energy from the surface to the atmosphere, necessary to achieve overall energy balance of the climate system, was explained by Herbert Riehl and Joanne Malkus (the latter better known as Joanne Simpson) in a 1958 paper, On the heat balance of the equatorial trough zone (Geophysica). Riehl and Malkus noted that boundary layer air, rising buoyantly in the protected updraughts of deep tropical convection clouds, converts heat and latent energy to potential energy. Away from the convection, compensating subsidence converts potential energy to heat.

What is implied in the Riehl and Malkus model is that deep tropical convection, and the transfer of energy from the surface to the atmosphere, will not take place without buoyant updraughts within deep convection clouds. That is, there is a need for the temperature of the atmosphere to decrease with altitude and that the rate of decrease of temperature must be sufficient to allow buoyancy of the air ascending in the updraughts. From well-known thermodynamic laws, the rate of decrease of temperature must be at least 6.5oC/km to allow the buoyancy forces of convection to overcome the natural stratification of the atmosphere.

The climate system will come into energy equilibrium when temperatures are such that the net solar radiation absorbed is balanced by the longwave radiation to space. At equilibrium, the greenhouse effect (ie, that the average surface temperature of 14oC is greater than the -19oC blackbody emission temperature of earth) is an outcome from the need for convective overturning of the atmosphere.”

Essentially, the role of greenhouse gases is to cool the atmosphere and this, with the surface warming from solar radiation, generates convective instability. It is the temperature lapse rate required for deep convection that leads to the ‘greenhouse effect’. But this takes the wind from the sails of the AGW folk.

William Kininmonth
Melbourne

Mr Kininmonth is the author of Climate Change: A Natural Hazard available from Amazons.

—————
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89 Responses to “William Kininmonth on the Radiation of Energy and Global Warming”

Pages: « 1 [2] Show All

  1. Comment from: Barry Moore


    This was a most interesting series of comments, the strange part about it is that there are elements of truth in a lot of the opposing views but an incredible amount of confusion and lack of understanding of the different mechanisms for the energy transfer within the atmosphere. The “greenhouse gas effect” basically only occurs in the long wave IR absorbing molecules #1 water vapour #2 CO2 ( methane, ozone, nitrous oxide, all insignificant)All these molecules absorb only specific radiation frequencies which are in their resonant frequency bands, in the case of CO2 only 8% of the outgoing IR spectrum will be absorbed. The molecule gains energy but transfers it by colliding with other molecules thus there is some heat extracted from the outgoing radiation and converted into an increased temperature of the gasses in the atmosphere. However once the frequencies have been removed they do not magically reappear so the CO2 at higher levels have nothing to work with. There is a little reradiation back to the surface from the energized CO2 molecules but this occurs only in the first 2 or 3 meters of atmosphere and is minor. Water vapour reactes in a similar manner but absorbes more energy than CO2 because it has more resonant frequency bands closer to the peak of the spectrum. The total greenhouse gas effect of CO2 is estimated to be 3 deg C which occurs in the first 50 meters of atmosphere by the 8% energy extracted and once removed from the spectrum there is no longer any energy left so increasing the CO2 has no effect. Now the big guy on the block is water droplets or aerosol. Aersols which include smoke, volcanic ash, fly ash etc. behave entirely differently, they will absorb the entire spectrum and reradiate the entire spectrum just like any black body thus they do behave like a blanket, the gasses because they are frequency specific do not.As has been said the other massive factor in the energy balance is the convective behaviour in the atmosphere. When air rises it expands and cools down by JT effect when it decends it is compressed and therefore heats up. It short the very large majority of backradiation comes from aerosols and very little comes from greenhouse gas molecules. One last thought there is a lot of energy transfer within the atmosphere but it must be remembered that when one atom or aerosol looses energy its temperature drops and the recipient of that energy will have a temperature rise so the net effect is zero, the only thing that effects the temperature of the earth is the transfer of energy between the surface and the atmosphere and in this regard I believe the convective heat removal is underestimated.

  2. Comment from: Barry Moore


    This was a most interesting series of comments, the strange part about it is that there are elements of truth in a lot of the opposing views but an incredible amount of confusion and lack of understanding of the different mechanisms for the energy transfer within the atmosphere. The “greenhouse gas effect” basically only occurs in the long wave IR absorbing molecules #1 water vapour #2 CO2 ( methane, ozone, nitrous oxide, all insignificant)All these molecules absorb only specific radiation frequencies which are in their resonant frequency bands, in the case of CO2 only 8% of the outgoing IR spectrum will be absorbed. The molecule gains energy but transfers it by colliding with other molecules thus there is some heat extracted from the outgoing radiation and converted into an increased temperature of the gasses in the atmosphere. However once the frequencies have been removed they do not magically reappear so the CO2 at higher levels have nothing to work with. There is a little reradiation back to the surface from the energized CO2 molecules but this occurs only in the first 2 or 3 meters of atmosphere and is minor. Water vapour reacts in a similar manner but absorbs more energy than CO2 because it has more resonant frequency bands closer to the peak of the spectrum. The total greenhouse gas effect of CO2 is estimated to be 3 deg C which occurs in the first 50 meters of atmosphere by the 8% energy extracted and once removed from the spectrum there is no longer any energy left so increasing the CO2 has no effect. Now the big guy on the block is water droplets or aerosol. Aerosols which include smoke, volcanic ash, fly ash etc. behave entirely differently, they will absorb the entire spectrum and reradiate the entire spectrum just like any black body thus they do behave like a blanket, the gasses because they are frequency specific do not. As has been said the other massive factor in the energy balance is the convective behavior in the atmosphere. When air rises it expands and cools down by JT effect when it descends it is compressed and therefore heats up. It short the very large majority of backradiation comes from aerosols and very little comes from greenhouse gas molecules. One last thought there is a lot of energy transfer within the atmosphere but it must be remembered that when one atom or aerosol looses energy its temperature drops and the recipient of that energy will have a temperature rise so the net effect is zero, the only thing that effects the temperature of the earth is the transfer of energy between the surface and the atmosphere and in this regard I believe the convective heat removal is underestimated.

  3. Comment from: Chris Crawford


    Alan, you write: “No, a sequence of excitation and emission occurs in a refractive medium.”

    No, that process would scatter the light. A few photons do collide with atoms and are absorbed, then later re-emitted — but they can be re-emitted in any direction. The photons that do not collide with the atoms continue through the medium affected only by the change in the local permittivity and — in rare cases — magnetic susceptibility.

    Cohenite, you have repeatedly accused me of ignoring the Pielke paper. I have not bothered responding to it because it doesn’t really raise any significant issues. Its main argument is that we need more data:

    “Because of the issues presented in this paper related to the analysis of multidecadal surface temperature we recommend that greater, more complete documentation and quantification
    of these issues be required for all observation stations that are intended to be used in such assessments.”

    And in fact the very title of the paper reflects its thrust:

    “Unresolved issues with the assessment of multidecadal global
    land surface temperature trends”

    This is not the giant-killer you seem to think it is. It’s not even particularly noteworthy. Yes, of course, we all know that we need to get more and better data. What’s so shocking about that?

    Oh, and yes, there are latitudinal considerations in assessing AGW; I mentioned these long ago. There’s nothing surprising or even interesting in that observation.

    Barry, I’d like to add an important point regarding your disquisition. Yes, water vapor has a larger effect than CO2, and water aerosols have an even larger effect, but those effects are historically constant and are part of the current equilibrium. The increase in atmospheric CO2 is changing that equilibrium, which is why we worry about it. You are quite correct in observing that the net direct effect of increasing CO2 is estimated to be at most 3ºC. However, we shouldn’t overlook the likelihood of positive feedback, which would result in a greater overall rise in temperature.

  4. Comment from: Peter


    Chris Crawford: “No, you misunderstand the process. The fire emits, say, 1000 watts of power. Let’s say that 10 watts of that power strike the poker, heating it until it reaches thermal equilibrium and is emitting 10 watts of power. A small part of that 10 watts — say 0.1 watt — will hit the fire, causing it to heat up ever so slightly, so that it emits 1000.1 watts of power. So now the poker is receiving 10.001 watts of power — this is an infinite series that converges to a finite value. It doesn’t go infinite”

    Disappointingly, I can only conclude from the above that you really don’t know what you’re talking about.

    The fire emits 1000 watts of power. Which means it’s LOSING 1000 watts of power. The fact that it must be receiving at least 1000 watts in order to emit 1000 watts is irrelevant – if it receives power continuously it emits, and therefore loses, it continuously, but that’s besides the point.
    The 0.1 watts it receives back from the poker DOES NOT mean that it now emits 1000.1 watts, it means that it effectively LOSES 999.9 watts.

    You CANNOT create energy out of nothing, whether it’s 1000000 watts worth, or 0.000001 watts worth.
    To suggest that the fire, or the Earth for thaqt matter, somehow GAINS energy from back-radiation, violates fundamental laws of physics – end of!

  5. Comment from: marco


    Newbie here and very inexpert so patience is required.

    Am I right in characterising Kininmonth’s argument pivoting on the point that because the earth’s surface has the capacity to retain 66 w per m sqd in excess of that which is radiated into space then the so called green house gasses have a negligible role in forcing future temperature increases?

    I understand that this may be a mischaracterisation if only because from the chart on which he bases his figures I can’t identify the net gain.

    A question to Barry. I have read on other blogs that aerosols can have a cooling effect. I am thinking of the particulate matter that spews forth from volcanic eruptions which in great volumes seems to force a downward dip in temperature as was noted afet Mt Pinitauba (sp?)

    Any help would be appreciated.

  6. Comment from: Chris Crawford


    Peter, this is a simple matter of accounting — keeping track of where everything goes. There’s no magic, no energy being created or destroyed. The fire is generating 1000 watts of power and emitting 1000 watts of power — it’s stable. 0.1 watts bounce back to it — so now it’s generating 1000 watts AND absorbing 0.1 watts. That tiny increment of power causes its temperature to rise very slightly, so that it emits slightly more power — 1000.1 watts. That’s necessary for equilibrium. It’s all just a matter of keeping the sums straight.

    Marco, Mr. Kininmonth has gotten the sums mixed up. The earth’s surface does not retain 66 Wm**-2 — if it did, it would heat up very rapidly. Place your face next to a 100W light bulb and your face will be absorbing maybe 20 watts — see how quickly your skin burns!

    To understand the diagram, just go through it step by step, tracing the power flow. It all adds up if you keep the parts straight. Mr. Kininmonth has gotten them mixed up.

  7. Comment from: marco


    Thanks Chris for the reply.

    What I meant was that I couldn’t identify his 66 watts as the top of the chart shows a balance of energy in/energy out. Thus my question asking if I had fairly characterised his argument as to my understanding without this surplus then his argument fails.

  8. Comment from: Chris Crawford


    Yes, his 66 watts comes out of nowhere. I’m sure that, if we dig around, adding and subtracting pairs of numbers selected from the entire set of numbers on the graph, we’ll eventually find a combination that yields 66. But the logic behind that combination is unlikely to make sense. But perhaps we should give Mr. Hininmonth the opportunity to himself explain where the 66 came from.

  9. Comment from: Peter


    Putting it another way:
    A variation of the 2nd Law of Thermodynamics – the Clausius statement: Heat cannot spontaneously flow from a material at lower temperature to a material at higher temperature.

    Therefore the fire cannot heat the poker to a temperature higher than itself, and it follows that the poker cannot, by any means, make the fire any hotter than it is.

  10. Comment from: Chris Crawford


    No, Peter, that’s not correct. Here’s the logical sequence, and you tell me which step (or steps) is incorrect, in your opinion.

    1. The fire heats the poker to a temperature lower than its own.
    2. The poker radiates power because it’s hot.
    3. That power travels out in all directions.
    4. Some of that power hits the fire.
    5. The fire absorbs that power.
    6. Because the fire has absorbed additional power, its temperature rises.

  11. Comment from: Barry Moore


    Marco you are quite correct aerosols have both a positive and negative forcing effect. During the day they intercept incoming short wave radiation and since they radiate as a sphere a lot of this energy goes straight back into space, so less gets to the surface ( negative ) however it does capture long wave outgoing and radiates some of it back ( positive). During the day it is net negative i.e. cloudy days are cool days but at night clouds are net positive, cloudy nights are warmer than clear nights. Sustained high levels of aerosols ( volcanoes ) will have a net negative effect.
    Chris I think you skipped the part where the first 50 meters of atmosphere removes all the available energy in the CO2 resonant wavebands. Thus it is in a saturated stable equilibrium, any transfer in the atmosphere without any contact with the surface is net zero effect, again completely stable. Your remark about water vapour being historically stable is unquestionably not true. At -50 deg C the saturated water vapour content of the atmosphere is 34 ppm at 25 deg C it is 25 000 ppm so from the south pole to the equator we have quite a large variation in concentration. Now if the world warms up there will be a considerable change in this concentration thus water vapour is not constant irrespective of temperature, far from it. With respect to this massive change in concentration the same laws of physics apply to water as to CO2 so how come if CO2 doubles from 300 to 600 we will have a runaway disaster but water can change from 34 to 25 000 without any adverse effect.

  12. Comment from: Chris Crawford


    Barry, you’re right, I didn’t mention the depth-response of CO2, but I’m not following your assertion that “the first 50 meters of atmosphere removes all the available energy in the CO2 resonant wavebands.”

    If that were true, then adding CO2 to the atmosphere wouldn’t have any effect, because all the available energy would have been absorbed. Perhaps you’re talking about absorption and re-emission at low altitudes? In any event, I didn’t think that the cross section for a single CO2 molecule for its IR band photons was high enough to permit 400 ppm to absorb ALL the incident IR in just 50 meters. Do you have numbers on that?

    I think you misunderstand my remark on water vapor. Of course it has high derivatives, both spatially and temporally. My point was that water vapor, while a more important GHG than CO2, is not being changed by humankind in the way that CO2 is being changed. For the purposes of AGW analysis, water vapor can be treated as a constant factor (although of course in modeling it plays a large role).

  13. Comment from: Peter


    1) The temperature of the fire (or the Earth, or any other body) is determined by the difference between the rate of energy input and the rate of energy output.

    2) Heat cannot flow from a colder body to a warmer one by any means – be it conduction, convection, radiation or a combination thereof, without work being done (like in refrigeration)

    Your argument violates both these fundamental laws, and therefore cannot stand.

  14. Comment from: Barry Moore


    Peter the solution to this discussion depends on the configuration. You are basically discussing Stefans law which states the net energy flow between two bodies A & B is in relation to the 4th power of Temp A minus the 4th power of Temp B, Clearly net energy cannot flow from a cool body to a hot body but take away B and all the energy from A is lost thus it reaches an equilibrium temperature dependant upon the rate of energy being generated in A, now if you keep the energy at a constant rate but interpose B some heat is returned to A so its temperature must go up to maintain the same energy outflow. One caveat here which may be mudding up the water if the poker is actually surrounded by the fire it will not increase the temperature of the fire the two bodies A & B must be separate for this law to apply.

  15. Comment from: Chris Crawford


    Peter, I’m disappointed that you refused to respond to my line of reasoning, preferring instead to simply re-state a form of 2nd Thermo. But at least this permits me to explain your misconception in your own terms. You are correct in observing that “Heat cannot flow from a colder body to a warmer one by any means – be it conduction, convection, radiation or a combination thereof, without work being done”. What you are neglecting is the fact that work *is* being done. You probably have some difficulty with this idea, because you may not be familiar with the thermodynamic definition of ‘work’. In this case, the work being done is the original transformation of chemical energy into heat energy inside the fire. And that work can be used to move heat from a lower-temperature reservoir to a higher-temperature reservoir — exactly as I have explained.

  16. Comment from: Curt


    Sorry Peter, but you just do not know what you are talking about. Chris is absolutely correct.

    1.) You say, “The temperature of the fire (or the Earth, or any other body) is determined by the difference between the rate of energy input and the rate of energy output.” No! The rate of change of internal energy is determined by this difference. If all of the change goes into temperature change, then the rate of change of temperature (not the temperature itself) is determined by this difference. Many of the posts here over the past week have gone completely off the rails by confusing rates of change with levels.

    2.) You say, “Heat cannot flow from a colder body to a warmer one by any means – be it conduction, convection, radiation or a combination thereof, without work being done (like in refrigeration)”. As Chris has pointed out, this only applies to NET transfers.

    It is vital to realize that the 2nd Law is at root probabilistic and statistical. It is only when you sum all of the energy transfers between two bodies of different temperatures that you get the (virtual*) certainty that there is a net transfer from the warmer body to the cooler body.

    When there is no temperature difference between the bodies, 50% of the interactions (whether conductive or radiative) transfer energy one way, and 50% the other way, so there is no net transfer. If one body is slightly warmer than the other, then, say, 51% of the interactions transfer energy from the warmer to the cooler body, and 49% transfer from the cooler to the warmer body. It is the 2% difference that yields a net energy flow from the warmer to the cooler body. (And as the temperature difference grows, the percentage difference grows as well.)

    This is true for both conductive interactions, where the atoms are directly colliding with each other and transfering energy that way, and for radiative interactions, where photons act as the intermediary.

    These concepts are easy to verify, both experimentally and conceptually. It is very easy to confirm in the lab — I’ve done it — that the thermal radiation from a body does not depend on the temperature of any bodies it is radiating toward. The argument that a cooler body cannot radiate any energy toward a warmer body demands a different result.

    And conceptually, the argument that a cooler body cannot radiate any energy toward a warmer body requires that bodies have “knowledge” of what they are radiating towards. What is the mechanism for obtaining and processing that knowledge? And since this radiation travels at the speed of light, wouldn’t the inhibiting signal have to come in faster than the speed of light?

    *Given the probabilistic nature of the 2nd Law, even this is not an absolute certainty, but on any macroscopic scale, the odds against something different happening are so vast they make the odds of striking it big in the lottery seem like a sure thing.

  17. Comment from: Peter


    Even if you surrounded object A with a perfect, lossless reflector which INSTANTLY reflected ALL the energy radiated from A back to A at the same wavelength, you would be doing nothing more than effectively reducing the rate of energy loss of A to zero. You would NOT be increasing the energy input to A.

    And as an analogy to my point 2, shining a torch at a brighter light does not increase the intensity of the brighter light.

  18. Comment from: Peter


    Even if you surrounded object A with a perfect, lossless reflector which INSTANTLY reflected ALL the energy radiated from A back to A at the same wavelength, you would be doing nothing more than effectively reducing the rate of energy loss of A to zero. You would NOT be increasing the energy input to A.

    And as an analogy to my point 2, shining a torch at a brighter light does not increase the intensity of the brighter light.

  19. Comment from: Chris Crawford


    Peter writes: “Even if you surrounded object A with a perfect, lossless reflector which INSTANTLY reflected ALL the energy radiated from A back to A at the same wavelength, you would be doing nothing more than effectively reducing the rate of energy loss of A to zero. You would NOT be increasing the energy input to A.”

    Yes you would. I assume you’re still talking about an object that is generating heat at some power P. Basically, what you’ve set up is a closed system: the object A is getting power coming into and there is no way for the power to escape. Therefore the temperature will rise indefinitely.

  20. Comment from: Chris Crawford


    Oh yes, I forgot this:

    “shining a torch at a brighter light does not increase the intensity of the brighter light.”

    Actually it does, but the amount of increase is very, very tiny.

  21. Comment from: Peter


    Curt: “And conceptually, the argument that a cooler body cannot radiate any energy toward a warmer body requires that bodies have “knowledge” of what they are radiating towards.”

    I never argued that a cooler body cannot radiate towards a warmer one, merely that the radiation won’t be absorbed by the warmer one.

  22. Comment from: Peter


    Chris: “One caveat here which may be mudding up the water if the poker is actually surrounded by the fire it will not increase the temperature of the fire the two bodies A & B must be separate for this law to apply.”

    Let me see if I’ve got this straight – if object A and object B are separate, and the only thermal transfer between the two is bwo radiation, A can heat B which in turn can heat A, but if B is surrounded by A then that cannot happen – even though B is hotter than it would be were they separate, and transfer can be bwo conduction and radiation?
    How does that happen?

    It seems that you occupy a very strange universe.

  23. Comment from: Curt


    Peter, you said, “I never argued that a cooler body cannot radiate towards a warmer one, merely that the radiation won’t be absorbed by the warmer one.”

    So how does the receiving body know whether a given photon is a less energetic one from a warmer body (which by your logic should be absorbed), or a more energetic one from a cooler body (which by your logic should be — what — reflected)?

    Remember that all bodies radiate away photons with a distribution of energies. Can you propose a mechanism whereby a photon of a given energy level carries with it information about where on the distribution of the radiating body it came from (does it carry a certificate)? And how is this information transmitted to the receiving body so it can make its decision?

  24. Comment from: Chris Crawford


    “It seems that you occupy a very strange universe.”

    Peter, the comment to which you object was made by Curt, but his meaning is clear. He’s trying to eliminate a more complicated situation that would be messier to analyze. Inasmuch as you’re having so much difficulty with the simpler case, I think it best that we keep things as simple as possible.

  25. Comment from: Chris Crawford


    Oops! And *I* misattributed it, too! The author of the statement in question is Barry, not Curt.

  26. Comment from: Peter


    The higher the temperature of an object, the higher energy photons it tends to emit, and the less its tendency to absorb lower energy photons – from whatever the source. Entropy increases.

  27. Comment from: Chris Crawford


    Peter writes: “The higher the temperature of an object, the higher energy photons it tends to emit, and the less its tendency to absorb lower energy photons”

    Peter, where do you get this notion? The first half is right, but the second half is just crazy. What possible physical mechanism could make this happen? This contradicts what we know about absorption processes. Didn’t you just make this up?

  28. Comment from: Curt


    Well Peter, maybe we’re making a little progress. You are starting to talk in terms of tendencies, which is a start to understanding the probabilistic nature of these things.

    But you still have not come to grips with the key issue, which is that your argument requires some decision-making mechanism between the two bodies about whether certain photons should be accepted or rejected.

    Two other implications of your argument: First, if the hotter body somehow could decide not to absorb any of the photons from the cooler body, it would have to reflect them away. If so, this would be detectable and measurable. Can you cite any work that demonstrates this phenomenon?

    Second, if your argument were true, the rate of power transfer would not be proportional to the differences in T^4. You would get a sudden step in power transfer when one body got slightly hotter than the other, because (according to your argument) it would suddenly be able to reject all of the photons from the other body.

  29. Comment from: SJT


    “It seems that you occupy a very strange universe.”

    When you get down to the world of quantum mechanics, it is indeed a very strange one. It obeys the laws of physics, in that a hot body will heat a cold one overall, but at the same time you will get a photon being sent from a cold body to the hot one.

    If you want to read more about the quantum view of the world, it only gets more and more bizarre. For example, a single photon of light passing through two slits at the same time.

  30. Comment from: Ender


    For everybody UC Berkeley have a great series of podcast lectures. One of them Physics for Future Presidents is particularly apt.

    How about we all have a listen to the these:

    http://webcast.berkeley.edu/course_details.php?seriesid=1906978397#17859

    The course creator Richard Muller is also a Steve Short type skeptic of climate change and proponent of nuclear power so I guess you can consider him free of lefty bias.

    So why not listen to the lectures and then see how your theories fit into real physics.

  31. Comment from: Ender


    And another resource:

    Physics 10/LS C70V Descriptive Introduction to Physics

    http://muller.lbl.gov/teaching/Physics10/PffP.html

  32. Comment from: Graeme Bird


    No mate you are barking up the wrong tree. You are a fraud. You are an idiot. Skeptics understand the global warming idiocy enough to know its a lie.

    Now lets have that evidence.

  33. Comment from: Barry Moore


    Chris I don’t know if you are still following this blog I have been elsewhere for a couple of days. Your question re the absorption of CO2 at 400 ppm is explained best in the paper by John Nicol – Climate Change, if you can not find it his e mail is jonicol@netspace.net.au it is the best paper dealing with this subject using the fundamental laws of physics. The law you need is Beer’s law to calculate the mean path of the CO2 resonant frequencies.
    Again I think you missed the implication of “At -50 deg C the saturated water vapour content of the atmosphere is 34 ppm at 25 deg C it is 25 000 ppm so from the south pole to the equator we have quite a large variation in concentration. Now if the world warms up there will be a considerable change in this concentration thus water vapour is not constant irrespective of temperature, far from it. With respect to this massive change in concentration the same laws of physics apply to water as to CO2 so how come if CO2 doubles from 300 to 600 we will have a runaway disaster but water can change from 34 to 25 000 without any adverse effect. “ It really does not matter whether the cause is anthropogenic or not, first study the effect of the change then figure out where it comes from. If the atmosphere is as sensitive to concentration changes as that ridiculous empirical formula published by the IPCC then this must apply to water vapour as well as CO2 and the water vapour content of the atmosphere is changing regionally by massive amounts how can you possibly put this into a computer model when the dew point is all over the map on a daily basis which is totally unpredictable.

  34. Comment from: Chris Crawford


    Barry, I think you misunderstand the point that I was making. My point was that we cannot attribute recent changes in global temperature to water vapor, because historically (over several hundred years) there is no evidence to indicate that it has increased. Yes, there are big differences between water vapor at the poles and water vapor at the equator — that’s why the poles are warming faster than the equator.

    “how come if CO2 doubles from 300 to 600 we will have a runaway disaster but water can change from 34 to 25 000 without any adverse effect.”

    Indeed, if water vapor concentrations increase, they will cause enormous problems. In fact, this is another one of those nasty positive feedback factors. All by itself, a doubling of CO2 concentrations will increase global temperatures by only a few degrees C. But a small increase in global temperatures will ALSO put more water vapor into the air, which in turn will lead to larger increases in temperature. I’m not at all dismissing the effect of water vapor — it’s one of the factors that magnifies the danger of CO2 emissions.

    “how can you possibly put this into a computer model when the dew point is all over the map on a daily basis which is totally unpredictable.”

    This is the difference between weather and climate. Yes, weather variables change rapidly. But for purposes of predicting climate (not weather), you don’t need to track these variables with that much resolution. You can rely on data averaged over a period of time and apply standard diurnal and annual variations.

  35. Comment from: Graeme Bird


    No water vapour won’t cause enourmous problems if it increases. This is the curse of the watts per square metre business again.

    Water vapour magnifies the variation of the sun on the troposphere. But it is the method by which the oceans cool down. This is something that you miss if you attempt to process the data all the way to watts per square metre.

    Looking at the more meaningful measure of imbedded oceanic energy, it is the water vapour which is cooling the oceans down. Transporting heat into space.

    It is an EFFECT of excessive warming, seen from the oceans point of view and not a cause. Seen from the troposphere’s point of view it is THE cause of warming but when it overheats it is bringing the problem to an end. Since it is cooling the oceans.

    From the stratosphere’s point of view it is an immediate cooler.

    I’m telling you be quits with WPSM. It robs all perspective. It makes people stupid. You could start off with a great understanding of earth systems and weather. And the WPSM model would whittle it away over time.

  36. Comment from: Barry Moore


    O.K. Graeme I certainly follow your logic and it is very reasonable but if all this warming is being transported up into the troposphere by water vapour why have we not seen the increase in troposphere temperatures in either the UAH or RSS data as predicted by the IPCC in their 4th report. My embedded point here is that both water vapour and CO2 level off in their forcing effect at a relatively low ppm level < 100 ppm this is proven in John Nicol’s paper ( and many others) this does not include water as and aerosol only as a gas. Thus the lack of any change in forcing effect with a large variation in concentration is in conformance with the laws of physics and observations.
    I do agree with you about WPSM , IPCC waffles on about them ad nausium page after page and it is all just smoke and mirrors.

  37. Comment from: Gary Gulrud


    Bill is definitively correct re: Back Radiation, it cannot meaningfully occur for two reasons.

    1. The emissivity of non-reflective solids is 3 orders of magnitude larger than low pressure, low temperature GHGs H2O & CO2. Even if the atmosphere is hotter by tens of degrees C, the surface OLR will render insignificant any returning radiation of GHGs in their direction.

    2. The fact that the air is heated by OLR is definitive proof that this region of the atmosphere is not in thermal equilibrium. Incoming flux exceeds outgoing flux, if minutely, and the result is increased kinetic energy of the entire molecular complement of the region, increased temp. This means the GHGs lose the absorbed energy to its neighbors by conduction and do not emit in direct relation to their rate of absorption.

    All of this is Thermodynamics, which is not introductory physics and is manifestly not required of Climate Science grads at any level, even those with physics concentrations.

  38. Comment from: kuhnkat


    It now becomes clear how Ender’s physics has become so warped.

    Ender, you really listen to stuff from Berzerkeley???

  39. Comment from: Jennifer Marohasy » Proof of the Atmospheric Greenhouse Effect: Arthur Smith


    [...] the specific contribution of carbon dioxide to global warming, nor does he deal with the issue of convective overturning, but in ‘Proof of the Atmospheric Greenhouse Effect’ he elegantly explains the greenhouse [...]

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