There is a minor change in the atmosphere, but it may soon become apparent that more GHGs means more cooling, because that is what GHGs do, they cool the atmosphere.         The premise that radiation is the whole story is obviously wrong, it is not in itself self regulating, but temperature is, because of water.          There is too much of this junk science accepted as gospel, you can do this as a gedanken experiment, have a box well insulated on 5 sides, with a window transparent to LWIR, and see if the LWIR flux causes it to warm any. I see now why you say greenhouse gases cool the atmosphere. Yes - if you have a warm atmosphere then the way that cools is by radiation into space by greenhouse gases. So a proper explanation of the greenhouse effect requires some detailed physics and mathematics. I've gome through the maths, but I've come up with a simply anaology which makes discussion easier. You can think of the atmosphere in part as a two-way motorway (thats what we drive cars on in England) of infrared photons. The earth surface is a hot plate at the bottom generating photons into the Up-carriageway. Without any atmosphere thats all you would have. The earth has to generate just enough up-photons to balance the suns heating (thats on a different motorway altogether - ignore that for now). So now we add in the atmosphere - this as you say does many things (convection, evaporation etc) but for now just think of what the greenhouse gases do. The greenhouse gas molecules act as infrared photon absorbers AND emitters. That means they stop some of the up-photons. They also generate new photons both on the up carrageway and the down carrageway. Then you have the extra complication that now you have down-photons the greenhouse gases will absorb some down photons as well. So-far-so-good, but with all this absorbing and emitting (warming and cooling of the atmosphere) you can rightfully question: surely it just all cancels out and the NET result is the same. The answer to this is simple but subtle: ultimately what ever else happens we know that the net traffic of photons must be more up than down. In fact up minus down is a constant fixed to acheive radiative balance with the sun. So now the maths (very simplified): No atmosphere:    up - 0       = constant With atmosphere: up - down = constant Clearly with atmosphere  we need more up than without atmosphere.  This can only be achieved by having a hotter earth surface to generate more photons. Now you can add in all the other effects like convection. Also the oxygen and nitrogen plays a role in the story which I have glossed over here. But the essence of the greenhouse is just this - no more or no less. Are you convinced?       I never had any doubts, but less than convinced that the greenhouse gases are the major part of atmospheric physics.        Thinking about an Earth with the N2 and O2 atmosphere, and no water or carbon, may help understand why the temperature regime on Earth is what it is.        Let's get the moon out of the way, it has no atmosphere, it rotates much, much slower than the Earth, it has no water, and it has less mass.         Now it should be immediately clear that just an N2 atmosphere at 1000 bar would definitely moderate the temperature of the Earth, there is even a problem, the N2 would have no way to cool other than a little contact with hill sides and perhaps a strong wind torus up in the tropics and down at the poles, but the rapid rotation of the Earth and it's size means the same wind could not circulate in one day.        Also, the up-down radiation required is too complex, Local Thermodynamic Equilibrium is partly maintained by LWIR, but at very short range.      Short range radiation and absorption is less speculative than a single up-down model.         The premise of high altitude CO2 warming the surface may not even be in the literature, it may be part of the extensive gossip line being parroted by the AGW nutcases.         Again, I suggest an insulated one meter cube box with one LWIR face, aimed first up for a few hours, then aimed down for a few hours, to see how much energy transfer there is by radiation.- Hide quoted text - - Show quoted text - I think I can tackle a few of your issues. First I've been thinking a bit about a pure nitrogen atmosphere (no WV,CO2) and what would happen. One thing is certain is that the atmosphere would be colder. Now in my pure model the atmosphere would drop to absolute zero and you would end up with nitrogen-lakes:         You obviously don't agree with the AGW nuts, they think the surface gets hot enough to warm the atmosphere 33 degrees from the average temperature of the moon, you must be lacking something in thinking the Earth would not only be colder than the moon or any other planet in the solar system, but could even cool below the temperature of the MWBG. so we need to first look at what else can heat the atmosphere.         What else?     You would have: - Some absorption of suns UV light - Convection from the hot earth surface          It is a little more than some on the moon. So an equilibrium would be reached where this heating matched the cooling from colder parts of the earth surface.        How do you propose warm air circulates to be in convective connection with the surface to reach an equilibrium? So what temperature would the earth surface be at when equilibrium was reached? We'll the only consistent answer I can give is that it would be pretty much the same temperature as the moon.          Even the AGW nuts are not that clueless. In other words the atmosphere has played a very passive role in the radiative balance.          Sure, LW IR radiation is all there is, conduction and convection is outlawed by AGW. [There is an interesting aside to this: on Titan the nitrogen pressure is so high that actually infrared radiation interacts with nitrogen-nitrogen collisions and so nitrogen becomes a greenhouse gas! This effect is minimal on Earth, but maybe without WV the nitrogen would get dense enough to be like Titan] Must go now - I'll come back to your other points.        Don't bother.- Hide quoted text - - Show quoted text - Ok I wont. I was trying to have a sensible discussion of physics with you, but you just say I'm clueless! It is not that AGW dont consider conduction and convection, its just that radiation is ultimately the only way the earth can cool into space. I did think your thought experiment of a nitrogen only atmosphere was a good one - maybe you could say what you think would happen (or refer to a previous post) then I can see why our thoughts dont align. You may have noticed by now that IMAGG is a time-waster.         At least he is thinking with an open mind, something you should try when you are laying on the beach there in Yucatan.

In LTE, everything within sight (in IR) is at nearly the same temperature, so all the photons ricocheting around are at equilibrium, and cannot carry net energy between _object_s at the same temperature.   Radiation from the surface is thus limited to an about 5u window around 10u which isn't affected by GHGs.  Clouds do stop it though. The rest of the energy must be carried up to the radiating level by convection. I think you'll find the Van Andel paper interesting.  He describes an experiment clearly showing the LTE between the surface and boundary _layer_, among other things.- Hide quoted text - Thanks - that will help me get going with the paper. Just one thing to check with you. I've been looking at the earth IR emission spectrum as seen from space. This window that you talk about is still quite a big effect (conventionally 40W/m2 of the total 235W/m2 radiation). The CO2 band lies as the edge of this window so increase in CO2 will eat into this window. Do you accept this bit? The hard bit I agree is understanding all the WV and cloud effects. Burroughs acknowledges this.

       The N2 atmosphere would moderate the temperature of the surface, convection would reduce the maximum high daily temperatures, and not as much, reduce cooling at night. So where have you got to: no atmosphere: -18C like moon add nitrogen: a bit of moderating actual earth: +14C Cause of +33'C?? Oh, greenhouse gases.

        There is a minor change in the atmosphere, but it may soon become apparent that more GHGs means more cooling, because that is what GHGs do, they cool the atmosphere.         The premise that radiation is the whole story is obviously wrong, it is not in itself self regulating, but temperature is, because of water.          There is too much of this junk science accepted as gospel, you can do this as a gedanken experiment, have a box well insulated on 5 sides, with a window transparent to LWIR, and see if the LWIR flux causes it to warm any. I see now why you say greenhouse gases cool the atmosphere. Yes - if you have a warm atmosphere then the way that cools is by radiation into space by greenhouse gases. So a proper explanation of the greenhouse effect requires some detailed physics and mathematics. I've gome through the maths, but I've come up with a simply anaology which makes discussion easier. You can think of the atmosphere in part as a two-way motorway (thats what we drive cars on in England) of infrared photons. The earth surface is a hot plate at the bottom generating photons into the Up-carriageway. Without any atmosphere thats all you would have. The earth has to generate just enough up-photons to balance the suns heating (thats on a different motorway altogether - ignore that for now). So now we add in the atmosphere - this as you say does many things (convection, evaporation etc) but for now just think of what the greenhouse gases do. The greenhouse gas molecules act as infrared photon absorbers AND emitters. That means they stop some of the up-photons. They also generate new photons both on the up carrageway and the down carrageway. Then you have the extra complication that now you have down-photons the greenhouse gases will absorb some down photons as well. So-far-so-good, but with all this absorbing and emitting (warming and cooling of the atmosphere) you can rightfully question: surely it just all cancels out and the NET result is the same. The answer to this is simple but subtle: ultimately what ever else happens we know that the net traffic of photons must be more up than down. In fact up minus down is a constant fixed to acheive radiative balance with the sun. So now the maths (very simplified): No atmosphere:    up - 0       = constant With atmosphere: up - down = constant Clearly with atmosphere  we need more up than without atmosphere.  This can only be achieved by having a hotter earth surface to generate more photons. Now you can add in all the other effects like convection. Also the oxygen and nitrogen plays a role in the story which I have glossed over here. But the essence of the greenhouse is just this - no more or no less. Are you convinced?       I never had any doubts, but less than convinced that the greenhouse gases are the major part of atmospheric physics.        Thinking about an Earth with the N2 and O2 atmosphere, and no water or carbon, may help understand why the temperature regime on Earth is what it is.        Let's get the moon out of the way, it has no atmosphere, it rotates much, much slower than the Earth, it has no water, and it has less mass.         Now it should be immediately clear that just an N2 atmosphere at 1000 bar would definitely moderate the temperature of the Earth, there is even a problem, the N2 would have no way to cool other than a little contact with hill sides and perhaps a strong wind torus up in the tropics and down at the poles, but the rapid rotation of the Earth and it's size means the same wind could not circulate in one day.        Also, the up-down radiation required is too complex, Local Thermodynamic Equilibrium is partly maintained by LWIR, but at very short range.      Short range radiation and absorption is less speculative than a single up-down model.         The premise of high altitude CO2 warming the surface may not even be in the literature, it may be part of the extensive gossip line being parroted by the AGW nutcases.         Again, I suggest an insulated one meter cube box with one LWIR face, aimed first up for a few hours, then aimed down for a few hours, to see how much energy transfer there is by radiation.- Hide quoted text - - Show quoted text - I think I can tackle a few of your issues. First I've been thinking a bit about a pure nitrogen atmosphere (no WV,CO2) and what would happen. One thing is certain is that the atmosphere would be colder. Now in my pure model the atmosphere would drop to absolute zero and you would end up with nitrogen-lakes: so we need to first look at what else can heat the atmosphere. You would have: - Some absorption of suns UV light - Convection from the hot earth surface So an equilibrium would be reached where this heating matched the cooling from colder parts of the earth surface. So what temperature would the earth surface be at when equilibrium was reached? We'll the only consistent answer I can give is that it would be pretty much the same temperature as the moon. In other words the atmosphere has played a very passive role in the radiative balance. [There is an interesting aside to this: on Titan the nitrogen pressure is so high that actually infrared radiation interacts with nitrogen-nitrogen collisions and so nitrogen becomes a greenhouse gas! This effect is minimal on Earth, but maybe without WV the nitrogen would get dense enough to be like Titan]   Titan has a surface pressure of around 150 bar, higher than even Venus.   (cut)   The surface pressure on Titan is about 1.5 bars, not 150 bars-

       The N2 atmosphere would moderate the temperature of the surface, convection would reduce the maximum high daily temperatures, and not as much, reduce cooling at night. So where have you got to: no atmosphere: -18C like moon add nitrogen: a bit of moderating actual earth: +14C Cause of +33'C?? Oh, greenhouse gases.        You sound dyed in the wool GHG trapping , I can only wonder how the gases that cool the atmosphere can warm it.        I have an open mind, but I need good physics to convince me, an almost lack of repeatable experiments is inexcusable, all the money is being spent on crystal balls.         Water is definitely a cooling factor, for both the surface and the atmosphere, for blocking incoming energy by clouds, for cooling the surface and lower few meters of air by evaporation, and for radiating outgoing energy to space.        If I thought the minor trace gas CO2 could do all that much absorbing and transferring the absorbed energy to the N2 and O2 for storage, it would make sense to be less skeptical, but one molecule to 2000 N2 and 500 O2 does not seem like enough to absorb more than a watt or so per square meter.         So I must assume that the surface and the water vapor does most of the absorbing and transferring of incoming solar energy to the N2 and O2 and that is where the energy is retained to enable an atmosphere that does not cool very much in 12 hours.         I see NO way whatsoever that upper atmosphere CO2 can warm the surface, the LWIR is absorbed in the tropopause and radiated to space.       That is why I want to see experiments to show downward LWIR radiation fluxes.

The hard bit I agree is understanding all the WV and cloud effects. Burroughs acknowledges this. You may be interested in this: <http://www.met.hu/doc/idojaras/vol111001_01.pdf (Dr. Ferenc Miskolczi) It's a different approach which fixes many of the errors in the IPCC dogma. Also this may help, if you haven't seen it: <http://upload.wikimedia.org/wikipedia/commons/7/7c/Atmospheric_Transm...