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Climate Hustle

Is CO2 a pollutant?

Posted on 11 February 2010 by John Cook

We commonly think of pollutants as contaminants that make the environment dirty or impure. A vivid example is sulphur dioxide, a by-product of industrial activity. High levels of sulphur dioxide cause breathing problems. Too much causes acid rain. Sulphur dioxide has a direct effect on health and the environment. Carbon dioxide, on the other hand, is a naturally occuring gas that existed in the atmosphere long before humans. Plants need it to survive. The CO2 greenhouse effect keeps our climate from freezing over. How can CO2 be considered a pollutant?

A broader definition of pollutant is a substance that causes instability or discomfort to an ecosystem. Over the past 10,000 years, the level of atmospheric carbon dioxide in the atmosphere has remained at relatively stable levels. However, human CO2 emissions over the past few centuries have upset this balance. The increase in CO2 has some direct effects on the environment. For example, as the oceans absorb CO2 from the atmosphere, it leads to acidification that affects many marine ecosystems. However, the chief impact from rising CO2 is warmer temperatures.


Figure 1: CO2 levels (parts per million) over the past 10,000 years. Blue line from Taylor Dome ice cores (NOAA). Green line from Law Dome ice core (CDIAC). Red line from direct measurements at Mauna Loa, Hawaii (NOAA).

Rising CO2 levels causes an enhanced greenhouse effect. This leads to warmer temperatures which has many consequences. Some effects are beneficial such as improved agriculture at high latitudes and increased vegetation growth in some circumstances. However, the negatives far outweigh the positives. Coast-bound communities are threatened by rising sea levels. Melting glaciers threaten the water supplies of hundreds of millions. Species are becoming extinct at the fastest rate in history.

How we choose to define the word 'pollutant' is a play in semantics. To focus on a few positive effects of carbon dioxide is to ignore the broader picture of its full impacts. The net result from increasing CO2 are severe negative impacts on our environment and the living conditions of future humanity.

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Comments 201 to 250 out of 252:

  1. Concentration and context matter.

    Certain forms of nitrogen compounds (nitrates, etc.) are a necessary nutrient for plant growth.

    But, too much nitrogen in aquatic systems can cause anthropogenic eutrophication and a resulting loss in biodiversity.

    Think scum filled ponds and dead zones in coastal zones.

    Most people have no issue regarding excess nitrogen as a pollutant. No different form CO2.
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  2. suibhne: Here are actual measurements of longwave IR radiation headed downwards towards the surface, measured at the surface. Figures 1 to 4. You can see the cartoon is correct in its order of magnitude. The actual numbers vary, based on where on earth you are, the humidity and clouds overhead, etc.


    http://www.arm.gov/publications/proceedings/conf12/extended_abs/morcrette-jj.pdf

    So yes, the atmosphere sends a lot of IR down, and you can measure it.
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  3. suibhne:

    And on the last page of this, you can see the solar radiation that reaches the surface, per area. As you might expect, this varies with latitude.

    http://www.sciencemag.org/cgi/data/308/5723/850/DC1/2


    Let's get back to basics, suibhne.

    Say you've got one wall at 25 C. Directly facing it is another wall, at 50 C. Behind each wall is some mechanism keeping the temperature of the wall perfectly constant. There is a perfect vacuum in the gap between the two walls. Both walls are perfect blackbodies. What are the energy flows?
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  4. To clarify: the map on the last page of http://www.sciencemag.org/cgi/data/308/5723/850/DC1/2 is estimated from satellite data, but from the preceding figures you can see that the calculations from satellite data match up very nicely with actual measurements at the surface.
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  5. To summarize what a couple of posts before mine say, your thermopile will never "read" these numbers because they are globally/temporally averaged flows.
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  6. doug_bostrom
    The flow of heat will always be from a higher to a lower temperature unless work is done.
    Heat can be prevented from flowing by addressing conduction convection and radiation issues
    I think we are all agreed on that I hope.
    Where the disagreements arise is on the overemphasis on radiation.
    I have a Physics degree and even my Thermodynamics textbook by Adkins(1985) gives the now abandoned Greenhouse explanation.
    Apparently he was not aware of the experiment by Woods.
    It was therefore important that G&T should clear up any doubts on the matter.
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  7. suibhne writes: The flow of heat will always be from a higher to a lower temperature unless work is done.

    That's the net flow of heat. It's perfectly possible for some heat to flow from a lower temperature to a higher, as long as there's a greater flow in the opposite direction. This is the point that G&T fail to understand (or one of the points).

    Thus, the atmosphere is cooler than the surface, so there's a net flow of heat from the surface to the atmosphere. That net is a result of a large flux from the surface to atmosphere and a smaller one from the atmosphere to the surface. Warming the atmosphere will increase the latter, therefore warming the surface.

    The fact that G&T fail to understand this completely non-controversial and very basic point ought to clue you in to the lack of merit in their paper as a whole.
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  8. carrot eater

    Thanks for posting these leads will look at them in more detail later.
    I realise that the diagram are discussing is averaged over say one year and you did not disagree that the readings I assumed that the thermopile would take.
    Yet you find nothing odd with them!

    Philippe Chantreau
    Given that we are talking about properly obtained and averaged values are you still happy with these readings?
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  9. Ned
    That's the net flow of heat. It's perfectly possible for some heat to flow from a lower temperature to a higher
    I think you are mixing up heat and energy definitions.
    A good thermodynamics text book will clarify the issue.
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  10. carrot eater

    ......Say you've got one wall at 25 C. Directly facing it is another wall, at 50 C.
    We are probably not in disagreement about this .
    Both walls will radiate to each other but the flow of heat is from the hotter wall to the colder.
    Where there does seem scope for disagreement is in the respective size of the heat loss from the surface of Earth by conduction convection and radiation
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  11. Suibhne, no Ned is completely (and obviously) correct.

    THINK about it.

    How would heat 'know' not to flow in a given direction? It doesn't... it radiates equally in all directions. There is no 'magical quantum traffic cop' preventing heat from traveling from a cold substance to a hot one. It happens all the time. However, since the hot substance is giving off MORE heat the amount flowing from it to the cold substance is greater and the NET change is always from the hot to the cold.

    The amount of heat coming up from the Earth is greater than the amount absorbed and reflected back (obviously, since the latter can only be a subset of the former), and thus the NET flow >is< from hot planet up into cold space... but the downward heat is greater than it would be without GHGs.

    It should be painfully obvious that this is true. Otherwise blankets could not work... clearly the blanket is colder than the human body so if G&T weren't liars or fools they're postulates would mean that since the human body is generating all of the heat in the 'blanket & body' system the heat MUST all flow from the body up to the blanket and the body will never be any warmer than it was without the blanket. That is, of course, complete nonsense. Some of that body heat is retained by the blanket and returned back down to the human, flowing from colder blanket to warmer human and making the human warmer than they would have been without the blanket.
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  12. CBDunkerson

    G&T have no problem with your blanket analogy -stops heat loss due to conduction and convection.
    The consider that heat loss by radiation is much smaller and that re radiation from the atmosphere is so small that it can be ignored.
    Even for radiation the heat flow is always from higher to lower temperature.
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  13. suibhne

    So you accept both walls will absorb radiation emitted by the other wall.

    And that's it. The end. You've just refuted G&T. We have shown you that it is this basic concept that G&T are refusing to accept. You think it's a matter of magnitude, of just how much radiation from the atmosphere is absorbed by the surface. The text of G&T simply does not support that. G&T are saying zero radiation from the colder atmosphere is absorbed by the Earth. It's a matter of principle, and as such, the game is over.

    And anyway, the magnitudes are fine. They have been measured.
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  14. carrot eater

    ..... The text of G&T simply does not support that. G&T are saying zero radiation from ....

    I think you must be reading a different copy from me.
    Where do G&T say that there is Zero radiation from Atmosphere to Earth!
    The main point I picked up was that the Woods experiment showed that radiation from the Earth to atmosphere is very small part of the total energy transfer.
    It then follows that re-radiation back to the surface is even smaller so that for practical purposes it can be ignored.
    This is quite common in Physics.
    A typical problem might be:
    A stone is dropped vertically from a cliff and lands 3seconds later.
    How high was the cliff.(ignore air resistance)

    On another tack and nothing to do with the previous discussions.
    What is the average path length travelled in the atmosphere by a suitable IR photon before it is absorbed by a CO2 molecule?
    I have heard quotes from 10m to 10 Km
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  15. suibhne: The text in question in G&T has been pointed out several times already, including the figure. They think the greenhouse effect is in theory impossible. This is not an argument of magnitude, but of principle.

    And again, you can see the magnitude of the measurements. They are in line with the Trenberth diagram that you find to be absurd.
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  16. I wrote: It's perfectly possible for some heat to flow from a lower temperature to a higher, as long as there's a greater flow in the opposite direction. This is the point that G&T fail to understand (or one of the points).

    suibhne responded: I think you are mixing up heat and energy definitions. A good thermodynamics text book will clarify the issue.

    No, I meant precisely what I said. The fact that the cooler atmosphere contributes to heating the warmer earth does not violate the 2nd LOT because the net heat flux is still in the opposite direction. G&T are spectacularly wrong on this, which is one (but only one) reason why their paper was greeted with such ridicule.

    Persisting in arguing this point, and citing G&T as if there was some merit to their nonsense, reduces your credibility and weakens the "skeptic" case. Steve McIntyre understands this, which is why he bans any discussion of G&T from his site. Here are a few examples of Steve's response when commenters have tried to bring this paper up for discussion there:

    "I do not want to discuss Gerlich on this site. I am not interested in expositions why the effect is impossible – it isn’t. Can people simply STOP posting 'skeptic' references on this."

    "Folks, I do not wish to get involved in a discussion of this paper by Gerlich and Tscheuschner. It would be far more worthwhile to discuss a good exposition of mainstream theory."


    Et cetera. McIntyre is smart enough to understand that hosting discussion of topics like G&T would significantly impair the credibility of his blog.
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  17. Ned
    Steve McIntyre is very good at analysing data,
    he famously showed that the hockey stick graph was a joke.
    His site is famous for subjecting data to a more rigorous investigation than the original authors were capable of.
    His site does not highlight any other theories about climate change such as the solar models etc.
    Ned do you think that heat is exactly the same as energy?
    If so I think that you do need to look this up in a reputable thermodynamics textbook because you obviously don't agree with me when I say it is not.
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  18. carrot eater
    ..... The text in question in G&T has been pointed out several times already, including the figure.

    I asked you to show me the text and you did not.
    So I can only guess that you also are getting mixed up between the definition of heat and energy.
    If this is the case, I think that you do need to look this up in a reputable thermodynamics textbook because you obviously don't agree with me when I say it is not.
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  19. This is truly bizarre.

    Suibhne, it's been pointed out to you before.

    "A machine which transfers heat from a low temperature reservoir (e.g., stratosphere) to a high temperature reservoir (e.g., atmosphere) without external work applied, cannot exist — even if it is radiatively coupled to an environment, to which it is radiatively balanced. A modern climate model is supposed to be such a variant of a perpetuum mobile of the second kind."

    Again, this is not an argument about magnitude. It is a clear statement that G&T think there is a violation of the Second Law in here.

    Where is the violation of the Second Law, suibhne?
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  20. Heat, in our context is IR radiation. It is a form of energy. How exactly do you disagree with this?

    G&T very clearly states that no IR radiation (heat) can flow at all from the atmosphere to the surface, as a matter of principle, not degree. They have been quoted already. If you continue saying that nobody has pointed you to where they say so, you will display an obvious lack of interest for a real exchange and your posts will probably be deleted.
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  21. Heat transfer is the transport of thermal energy, through conduction, convection or radiation. I don't know why suibhne is trying to play with semantics, but it won't go anywhere.

    But let's not have that distract from the main question. Where in the Trenberth diagram is there a violation of the Second Law?
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  22. carrot eater Philippe Chantreau

    It has just occurred to me that perhaps you don't have any Physics text books to consult.
    From University Physics by Harris Benson page 382
    Modern definition of Heat
    Heat is energy transferred between two bodies as a consequence of a difference in temperature between them.
    Hope that helps.
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  23. So what, you can quote a textbook with one definition and that's a big gotcha? I'm unimpressed. Heat is used loosely in many circumstances and often refers to enthalpy as well, since it can be readily translated in terms of heat. You're just playing on words, just like G&T.

    The wiki on heat is more informative than your definition:
    http://en.wikipedia.org/wiki/Heat

    You still haven't told us what the double sided panel was about, or where the violation of the 2nd law is.

    If anything you're proving that G&T are confused since they equate heat with IR in their paper. There is no heat transfer between the atmosphere and the surface. The heat transfer occurs between the surface and the atmnosphere. G&T say that, because there can be no heat transfer between atmosphere and surface, there can be no IR flowing from atmosphere to surface and that's simply stupid. The atmosphere's radiative properties owed to GH gases constrain the heat transfer, but the net heat transfer is still from surface to atmosphere. I don't know what your problem is and frankly I don't care any more.
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  24. Philippe Chantreau carrot eater

    The definition of heat is most important and you will fall into error if you use a "pass with a shove loose definition".
    That's why I asked you to look up the definitions in a thermodynamics textbook.

    Where in the Trenberth diagram is there a violation of the Second Law?

    A above the Stratosphere 342w/m2-agreed?

    B Just above the Earths surface 390w/m2 up + (168+324)w/m2down = 882w/m2-agreed?

    You agree, do you not think this is rather odd?

    This diagram shows that the available energy at surface is almost three times that supplied by the Sun.
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  25. suibhne:

    It isn't "odd" unless you can clearly state where there is a violation of the First or Second law in the greenhouse theory. G&T claim a violation of the Second Law. If you cannot articulate and defend this violation, then you must abandon G&T.

    This is now beyond unproductive. We are trying to be patient and polite, but patience is wearing thin.
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  26. carrot eater
    This atmospheric forcing of co2 is really powerful almost three times as much energy available at the surface as supplied by the Sun.
    Its a pity about the inconvenient facts of thermodynamics but they will not fade away.
    Any theory or computer model based on stuff like this must fail as it does not correspond to reality.
    I don't know who the "we" are in your last post I only speak for myself,but I never find it hard to be polite.
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  27. suibhne, the level of energy flowing/exchanging at the surface IS much larger than the level of energy at the top of the atmosphere, due entirely to the insulating properties of the atmosphere. If we didn't have an atmosphere the surface of the Earth would resemble the Moon; 107C average during the day, -153C average at night, summing to -46C surface temperature. As it is the average surface temp of the Earth is (sorry for vagueness, folks) around 15C, over 60C warmer.

    Without the atmosphere the surface of the Earth would quickly cool to match incoming solar irradiance. The outgoing energy from the surface (390 w/m2, plus 24 in conduction and 78 evaporative, according to the figure we've been discussing) is kept at ~15C by solar irradiance _AND_ heat reflected down from the atmosphere (342 or so?). Increasing CO2 will cause more heat to be retained by the atmosphere, directly resulting in a warmer atmosphere and surface - that's very simple.

    suibhne, you continue to construct incomplete thought experiments (your double IR solar panel), argue over definitions of heat and energy, and quite frankly insult other posters thermodynamic knowledge, but it really is this simple: the atmosphere insulates the earth and allows it to be >60C than the moons surface with the same irradiance. Increasing the insulating properties of the atmosphere with higher CO2 (and through positive feedback water vapor) levels will make the earth warmer. Hence global warming...
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  28. Gah - sorry, bad simple math, typing too fast: The moon has 107-153/2 = -23C average surface temp, versus ~15C average surface temp on Earth, difference of 38C.

    Difference between the moon's -23C and Earth's 15C surface temp is due to the insulation of the atmosphere, and the high levels of energy interchange at the surface are because the surface is WARM. It's that simple, suibhne.
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  29. That you would total up opposing IR flows as "available" energy confirms my doubts on your overall understanding of the process. Such an abuse of language is rather suprising from someone posing as a stickler on definitions.

    As for this question: "do you not think this is rather odd?"
    No, I don't. The nice climate we've been enjoying, sustained with only 342 w/sq.m exchanged at the surface, would be the oddity.
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  30. suibhne: It's more than just CO2; water vapor accounts for more of it than CO2.

    You are just giving emotional objections at this point - that something just doesn't sound right to you, for unexpressed reasons. That isn't sufficient. Again, please clearly state where there is a violation of the Second Law. G&T think there is one; do you agree?

    As for not corresponding to reality: I've shown you that these things can be measured. Longwave IR coming down towards the surface is not at all negligible. Reality is the greenhouse effect. Without it, the Earth would be a rather cold place.
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  31. KR, when using the Moon as an example, keep in mind that the Moon has a lower albedo than the Earth. So if there were no greenhouse effect, the Earth would actually be even colder than the Moon.
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  32. Ned carrot eater Philippe Chantreau KR

    You seem to insist that HEAT flows from a lower temperature atmosphere to a higher temperature planet.
    No Physics or Thermodynamics textbook will support you in this.
    However if you say that co2 and water vapour form a machine to do work on the atmosphere then at least we could look into that.
    As far as I know no body is prepared to be as explicit as this.
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  33. Ned carrot eater Philippe Chantreau KR

    You seem to totally ignore the atmospheric insulation provided by conduction and convection effects.
    The wind and tides redistributing thermal energy around the planet.
    Geothermal effects, resistive effects, wave thermal effects, in keeping the planet warm.
    Overemphasis on radiation, will distort the reality of the situation.
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  34. Suibhne wrote: "You seem to insist that HEAT flows from a lower temperature atmosphere to a higher temperature planet.
    No Physics or Thermodynamics textbook will support you in this."

    This central argument in the G&T paper is, evidently, an article of faith on which you will not be swayed.

    It is however clearly false. As has been shown in countless examples to the contrary. Were it true the 'effective temperature' and 'actual temperature' of all planets would be the same (and Earth a large ball of ice), two heat lamps in close proximity would result only in the cooler one warming while the warmer one is magically unaffected by the other heat source, those reflective space blankets wouldn't work because they are colder than the human body they are applying heat to, and so on through the various thought experiments you have been unable or unwilling to follow.
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  35. CBDunkerson

    It is impossible for HEAT to flow from a lower temperature atmosphere to a higher temperature planet unless work is done on the system to make it possible.

    Why do you think that every Physics or Thermodynamics textbook would back me up on this?
    The laws of thermodynamics were there before and after any supposed new theory such as Greenhouse theory.
    They can not be set aside.
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  36. Actually, both the discovery of the greenhouse effect and thermodynamic laws were first announced in 1824.

    However, the problem here isn't that the greenhouse effect violates the laws of thermodynamics... it is that you don't understand those laws. As you are attempting to apply them the Earth could be no warmer than the temperature generated by incoming solar radiation... yet it is ~32 C warmer. The planet is NOT a solid ball of ice. Ergo, your understanding MUST be incorrect. How is that possible? Well, for starters you are trying to determine entropy while leaving the energy SOURCE (i.e. the Sun) out of your system of observation (atmosphere and planet only).
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  37. suibhne

    Finally, you've decided to explicitly accept the G&T position.

    OK. Now, where in the Trenberth diagram is heat flowing the wrong way, suibhne? Please point out exactly where the wrong way transfer is.
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  38. suibhne: Once again you mistake the tree for the forest. Simple black body radiation (yes, simplifying for this discussion) emits from any object at levels corresponding to temperature. The Earth radiates the ~390 w/m2, plus another 100+ or so in conduction/evaporation. [Note that the measured bidirectional energy flow is 4x higher in radiation than conduction/convection.] The atmosphere radiates 342 (note, less!) towards the Earth. That and the 168 solar irradiance sum to (wait for it) 0.

    That's important, suibhne, _zero_. This is a steady state thermodynamic balance, and WORK is not being done. The atmosphere bounces a great deal of the energy emitted by the earth right back to it (like a silvered thermal blanket) - no work is done, just a different steady state condition than with no atmosphere. You have again argued from a portion of the equation, not the sum; looking at a part of the energy flows rather than the summation.

    As for the Earths surface being warmer than space, the solar irradiance impinges on the earth, lower wavelength/lower energy (IR) is emitted (simple entropy there, the earth isn't a perfect mirror), and CO2 with an IR absorbance peak retains it.


    Enough said. You first need to look at the summations in the steady-state thermal diagram, and realize that if work is being done it wouldn't be steady-state.

    Second, "It is impossible for HEAT to flow from a lower temperature atmosphere to a higher temperature planet unless work is done on the system to make it possible" realize that the presence of something warm (the atmosphere) keeps neighboring things warm (the Earth) by slowing/balancing energy emission rates. Again, this is a summation of all energy flows.

    And third, the energy flows of IR, conduction, and evaporation are easily measured and known - the GT assertions apparently denying IR energy exchange to the contrary are simply and provably wrong.


    I realize this isn't the last word on the topic; I assume that you will have some response. However, this is the last that I will post unless you have an actual and substantive point.
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  39. G&T are the ones trying to obfuscate things by equating IR radiation and neat heat, and you swallowed it hook, line and sinker.
    I'll quote myself: "heat flows from the surface to the atmosphere."
    That's a short, albeit accurate summary of the Trenberth diagram and I'm very confident that thermodynamics are on my side with this statement, you disagree?

    It does not prevent some IR radiation from flowing between atmosphere and surface. You can disagree with that if you want but I'll still trust the instruments measuring it and calculations showing it.

    You've been asked repeatedly to show where the Trenberth diagram violates any TD law. You keep on saying it does without having provided an answer. You have nothing of interest to say.
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  40. carrot eater KR CBDunkerson Philippe Chantreau

    It is impossible for HEAT to flow from a lower temperature atmosphere to a higher temperature planet unless work is done on the system to make it possible.

    This is not a wild throw away remark but is the settled view of the Physics community.
    It would make more sense if you would say explicitly that CO2 and water vapour are a machine that works on the atmosphere to pump heat to the surface from the atmosphere.
    This would then take the discussion back to other familiar situations and conclusions could be drawn.
    I understand that you would like me to say that IR radiation is exactly the same as heat but I am afraid that it is not.
    More interesting is the news that there is perhaps a peer reviewed article addressing the same area as the G&T paper.
    Perhaps the publication of this paper will move the discussion on.
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  41. From the wiki:

    "In thermodynamics, work performed by a system is the quantity of energy transferred by the system to another due to changes in the external parameters of the system. If these changes happen in a reversible way, then the performed work does not lead to a change of the entropy."

    "Work can be zero even when there is a force. The centripetal force in a uniform circular motion, for example, does zero work since the kinetic energy of the moving object doesn't change. This is because the force is always perpendicular to the motion of the object; only the component of a force parallel to the velocity vector of an object can do work on that object. Likewise when a book sits on a table, the table does no work on the book despite exerting a force equivalent to mg upwards, because no energy is transferred into or out of the book."

    Work requires a NET TRANSFER of energy. A balanced thermodynamic system does no work, even if energy (carried by IR, convection, conduction in the current discussion) flows both directions between those systems. In this regard the atmosphere is our table, the earth is our book - force is applied, no work is done, but the steady state condition is that the book is off the floor. Heat flow/entropy delta (net change) is zero for a steady state thermodynamic condition, energy flow isn't.

    Stop willfully confusing net entropy changes (heat) with balanced energy flows.

    Now if the steady state condition is disturbed (more CO2 blocks more long wavelength IR, more insulation) steady state temps on the surface will change to a point where the net energy flow is again zero (a hotter surface that radiates enough to compensate for the insulating properties of the atmosphere). Heating and cooling are directly reversible, and hence no change in entropy occurs (see first quote).


    suibhne, you've repeated yourself multiple times with that error about heat flows. It's not heating in a steady state system, regardless of non-zero bidirectional energy flows; no work is done.
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  42. Suibhne "I understand that you would like me to say that IR radiation is exactly the same as heat but I am afraid that it is not."

    But that's exactly what you're saying, in fact. You're saying that, because the heat transfer must be from hot to cold (surface to atmosphere), IR radiation from atmosphere to surface can not exist. At all. So, whether you realize it or not, you are indeed saying that IR is heat. Or, at least that's what G&T are saying, and you seem to agree with that.

    I don't know how to say it so that you understand: the heat transfer happens from the surface to the atmosphere. Do you dispute that? Can you look at Trenberth diagram and see that it is actually what is represented there?

    If not you are experiencing a fulminant case of Dunning-Kruger syndrome. Nothing anyone can do.

    As for the entire system, at TOA, there is 342 in and 342 out. KR explains the rest fine.
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  43. suibhne: The net exchange between surface and atmosphere is in the direction from surface to atmosphere. There is no problem here.

    Remember my example of the wall at 25 C and the wall at 50 C? Based on your current reasoning, it would be impossible for the 25 C wall to emit any radiation that is then absorbed by the 50 C wall.

    You've already admitted that such radiation does take place, so now you are arguing against yourself.

    As your statements are now inconsistent with each other, please clarify an argument. In so doing, show exactly which flow in the Trenberth diagram is objectionable, for which thermodynamic reason.
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  44. I've had interesting discussions with friends regarding entropy and the Earth. The energy flow from the Sun at 342 w/m2 enters and leaves - the Earth acts like a pass-through at that macro level. Due to the insulating properties of the atmosphere, local entropic reversal through plant growth, and other effects, the energy level at the surface _appears_ anomalously high.

    But if you think of the Earth as an energy "bucket", it becomes clear. Incoming energy falls in, an equivalent amount pours out, while the Earth holds a continuously overturning level of energy. What we're looking at with global warming is that the edges of the bucket are getting higher (more insulation), and the level of energy at the surface of the Earth increases. That doesn't change the steady state input/output rates.
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  45. carrot eater KR CBDunkerson Philippe Chantreau

    I think we are starting to repeat ourselves here.
    There is no point in restating positions endlessly.
    As I have stated, a peer reviewed article maybe passed for publication going over the same ground as G&T and will no doubt be commented on.
    Thank you for an interesting discussion.
    This forum provides a space where rational discussion can take place.
    This is a topic where irrational emotion based mud slinging is all to common and does neither side of the debate any good.
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  46. Ugh. All that effort, for no resolution?

    Just note the inconsistencies in your own statements. First the problem was of magnitude, not principle. Then, you changed and there was a Second Law problem. But you couldn't find anyplace where net heat transfer went in the wrong direction.

    You must realise that G&T's argument won't allow for the 25 C wall to radiate towards the 50 C wall. This is simple stuff, which is why the scientific community can just dismiss G&T out-of-hand. It's just that wrong.
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  47. I've just been reading the G&T paper. Oh, my.

    To quote Wolfgang Pauli "This isn't right. This isn't even wrong."
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  48. yeah. a lot of G&T is just irrelevant.

    I'm inclined to guess that nobody really reviewed it; it's not just bad, but it's full of inappropriate language.
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  49. I'm afraid that I have misled the readers of this thread.

    I thought that a peer reviewed article was about to be released. Instead it is a comment.

    Chris Ho-Stuart one of the authors addmitted

    None of my co-authors are prominent as physicists.

    The reference is: Joshua Halpern, Christopher M. Colose, Chris Ho-Stuart, Joel D. Shore, Arthur P. Smith, Jörg Zimmermann (2010) Comment On “Falsification of the Atmospheric CO2 Greenhouse Effects within the Frame of Physics”, (to appear in) International Journal of Modern Physics (B), Vol 24, Iss 10, March 30 2010.

    Is there no one with a background in thermodynamics that can give G&T a reasonable debate?
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  50. suibhne writes: Is there no one with a background in thermodynamics that can give G&T a reasonable debate?

    Actually, a number of those coauthors have already explained the problems with G&T in various blog posts etc. elsewhere. But it will be nice to have something appear in a journal.

    If I were you I'd drop G&T and find some more productive ground for climate skepticism. This one is a lost cause.
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