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Post by jimcripwell on Jul 11, 2009 14:06:09 GMT
Some weeks ago, I had an inconclusive discussion with glc about radiation at the TOA. On another blog, I THINK, I have found what I was looking forf. I dont pretend to really understand this, but I think glc's arguments were based on the idea that radiation is in balance at the TOA. The claim is made that this is wrong. The earth's climate tries to restore the radiation balance at the TOA, but never succeeds. Because of this, the calculations which glc used just dont work. Can I be proivided with a reference which proves that the TOA is always in radiation balance? I hope this question makes sense.
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Post by northsphinx on Jul 11, 2009 22:30:30 GMT
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Post by glc on Jul 12, 2009 8:48:34 GMT
Some weeks ago, I had an inconclusive discussion with glc about radiation at the TOA. On another blog, I THINK, I have found what I was looking forf. I dont pretend to really understand this, but I think glc's arguments were based on the idea that radiation is in balance at the TOA. The claim is made that this is wrong. The earth's climate tries to restore the radiation balance at the TOA, but never succeeds. Because of this, the calculations which glc used just dont work. Can I be proivided with a reference which proves that the TOA is always in radiation balance? I hope this question makes sense.
The earth is probably never truly in balance. It's always either gaining more energy than it's losing - or vice versa. This is due to lots of things - not just CO2. But the key point is that the earth will "try" to re-establish equilibrium. If, for example, more CO2 means that less energey is emitted from the TOA, then the earth will heat up until the energy balance is restored. At the same time, though, lots of other natural factors will be being played out. But, if we assume that the natural factors are broadly cyclical, e.g. solar cycles, PDO, AMO etc, we should be able to calculate the long-term effect of more CO2. The calculations that I gave do work because they calculate the change in energy at TOA due to the increase in CO2. From which we can calculate by how much the earth will need to heat up to restore balance.
I don't buy this argument about the earth never being in radiative balance. In fact there isn't really an argument. It's just an attempt to confuse the issue.
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Post by jimcripwell on Jul 12, 2009 10:45:37 GMT
glc writes "I don't buy this argument about the earth never being in radiative balance. In fact there isn't really an argument. It's just an attempt to confuse the issue. "
Fair enough. Do you have a reference which proves that the TOA is sufficiently in radiatve balance so that your calculations are substantially correct? You may not buy the argumant, but where is the science?
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Post by steve on Jul 12, 2009 11:39:50 GMT
glc writes "I don't buy this argument about the earth never being in radiative balance. In fact there isn't really an argument. It's just an attempt to confuse the issue. " Fair enough. Do you have a reference which proves that the TOA is sufficiently in radiatve balance so that your calculations are substantially correct? You may not buy the argumant, but where is the science? It's first principles in physics that energy is conserved. If TOA is not in radiative balance we would see a change in the energy content of the earth system (change in temps, ocean heat content, amount of ice etc.) All the observations of earth's radiation budget have taken place since the addition of extra CO2 that has put the energy balance out. Therefore, currently the TOA is usually out of radiation balance. A plot was included in this article: earthobservatory.nasa.gov/Features/OceanCooling/page2.php
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Post by curiousgeorge on Jul 12, 2009 12:16:21 GMT
It's been mentioned before that the climate/weather is a chaotic system. I submit that the climate is only 1 of a nearly infinite number of chaotic systems that interact with each other in ways we will never understand. Wheels within wheels, each having the attributes of a chaotic system - self organization, strange attractors, etc., from DNA to cosmic rays. Geologic, hydrologic, solar, and on and on. Trying to separate out one of those chaotic systems from the many others strikes me as a hopeless task.
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Post by icefisher on Jul 12, 2009 18:31:48 GMT
But, if we assume that the natural factors are broadly cyclical, e.g. solar cycles, PDO, AMO etc, we should be able to calculate the long-term effect of more CO2. The calculations that I gave do work because they calculate the change in energy at TOA due to the increase in CO2. From which we can calculate by how much the earth will need to heat up to restore balance. You do not have to just assume they are broadly cyclical, you have to assume you know them all. Cycles in nature tend to be complex. Its not a sound wave or 110 Volt ac. Thus there is little reason to believe you can broadly assume what they are. I suppose I can assume what your reaction to this comment will be and thats a natural cycle. . . .but the populations have moved global warming to or near the bottom of the list of their concerns. . . .which just makes you an outlier.
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Post by jimcripwell on Jul 13, 2009 11:32:11 GMT
glc seems to have deserted the discussion. Let me philosophize a little. When “scientists” started investigating AGW, it must have been obvious to them that it would never be possible to get experimental data to show that if you increased the amount of CO2 in the atmosphere, from current levels, then global temperature anomalies would rise. They needed to end run this problem.
Over 100 years ago, someone suggested the idea of radiative forcing (RF). This idea was almost immediately abandoned; there were at least two main objections to it. First, RF can never be measured; so it can never be physics. Second, any estimated value had to be based on an overly simplistic idea of how the atmosphere worked, so that any numbers obtained were meaningless.
This did not deter the warmaholics. There never can be any experimental data, and they could pretend that the advent of high speed digital computers had made it possible to describe the atmosphere in sufficient detail, that any numbers obtained had some meaning.
If you read the definition of RF carefully in the TAR, it is clear it describes a hypothetical situation. However, people like Myhre use computer programs, (radiative transfer models), which solve real problems. When I asked glc for a reference showing that radiative transfer models are suitable to estimate a value for RF, he could not provide such a reference. Not surprising, since my research indicates that no such reference exists.
However, glc does all sorts of calculations on radiation at the top of the atmosphere (TOA), which are only valid if there is radiative balance at the TOA. I have asked him for a reference showing that there is, indeed, radiative balanced at the TOA; again no reference. This time, I am not quite so certain, but I doubt that such a reference exists, since my research indicates that there is no radiative balance at TOA. Hence, all glc’s fine numbers seem to be meaningless.
AGW seems to me to be less like science, and more like the Gilbert and Sullivan’s comic operetta The Mikado. Here Poo-Bar, The Lord High Everything Else says, WTTE, “Tell me your fiction and for a small bribe, I will endorse it for you”. Unfortunately, the fundamental science of AGW seems to be more like Shakespeare’s Hamlet; “Something is rotten in the state of Denmark”
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Post by woodstove on Jul 13, 2009 13:41:30 GMT
A digest of glc's remarks:
"The earth is probably never truly in balance.... I don't buy this argument about the earth never being in radiative balance. In fact there isn't really an argument. It's just an attempt to confuse the issue.
[/quote]
Who's confusing whom? ;D
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Post by glc on Jul 13, 2009 14:06:05 GMT
However, glc does all sorts of calculations on radiation at the top of the atmosphere (TOA), which are only valid if there is radiative balance at the TOA.
No this is wrong - and this is exactly what I mean about trying to confuse the issue. If you reduce the amount of energy which is emitted from the TOA then the earth will warm until the incoming/outgoing balance is restored.
What do you mean that the calculations are only valid if there is radiative balance at the TOA. The whole point is that if the ghg concentration changes then the energy balance will change.
I believe you are confusing 2 separate points. Neither of which makes much difference to the calculations governing IR transmission through the atmosphere.
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Post by icefisher on Jul 13, 2009 14:21:37 GMT
This did not deter the warmaholics. There never can be any experimental data, and they could pretend that the advent of high speed digital computers had made it possible to describe the atmosphere in sufficient detail, that any numbers obtained had some meaning. What we have in this end run is a megaviolation of the first principles garbage in, garbage out law.
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Post by glc on Jul 13, 2009 14:23:46 GMT
"The earth is probably never truly in balance...."
Just think about the day/night cycle.
I don't buy this argument about the earth never being in radiative balance. In fact there isn't really an argument. It's just an attempt to confuse the issue
By which I mean the fact that we have day/night, winter/summer, ENSO fluctuations etc is neither here nor there in the grand scheme of things. If we add CO2 to the atmosphere, we change the radiative balance and the earth will attempt to correct for this change. If we have more incoming energy than outgoing then the earth must HEAT up. If we get an average of 240 w/m2 from the the sun but only 236 w/m2 is being emitted from the TOA, the earth will heat up until 240 w/m2 is being emitted.
These are basic truths. They are nothing to do with GCMs - or Al Gore or Jim Hansen or anyone else you don't like. I'm sorry if it's difficult to accept but CO2 does absorb IR radiation. It's plainly evident in emission spectra measured from above the earth's atmosphere.
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Post by jimcripwell on Jul 13, 2009 14:42:59 GMT
glc writes "These are basic truths. They are nothing to do with GCMs - or Al Gore or Jim Hansen or anyone else you don't like. I'm sorry if it's difficult to accept but CO2 does absorb IR radiation. It's plainly evident in emission spectra measured from above the earth's atmosphere. "
I will not argue. But if the TOA is not in radiatve balance, then the radiation which escapes from the TOA is not solely a function of radiation. It is also a function of conduction, convection, and the latent heat of water. And these factors must be accounted for. I asked for a reference to show that the TOA is in radiative balance. You have no such reference, and the TOA is not in radiative balance. And, therefore, all your nice calculations are so much garbage.
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Post by glc on Jul 13, 2009 15:18:33 GMT
I will not argue. But if the TOA is not in radiatve balance, then the radiation which escapes from the TOA is not solely a function of radiation. It is also a function of conduction, convection, and the latent heat of water.
This is nonsense. Energy which escapes to space from the TOA can only do so by radiation. That's the whole point. Convection, latent heat transport etc can move energy from the SURFACE into the atmosphere.
But it is only by radiation that the ~235 w/m2 is emitted at TOA.
And these factors must be accounted for.
They are.
I asked for a reference to show that the TOA is in radiative balance. You have no such reference, and the TOA is not in radiative balance.
It is. It must be else we would continue to warm (or cool). that's how radiative balance is achieved.
And, therefore, all your nice calculations are so much garbage.
You need to think a bit more before you post. I don't know who or what your source is for this latest attempt at debunking the greenhouse effect, but you've either misunderstood what's been said or the source doesn't know what they're talking about.
UPDATE: This is from Northsphinx link on TOA balance
"This incoming energy, sometimes called solar insolation or downward shortwave radiation, needs to be balanced. Why? Well, if it is not balanced by an equal loss of energy, then the temperature of the system must change (this is the 1st law of thermodynamics) "
Have you got that. If the incoming solar radiation is not balanced by an equal loss of energy then the temperature of the system must change.
It is ultimately only by radiation that this energy loss can be achieved.
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Post by steve on Jul 13, 2009 16:18:06 GMT
glc writes "These are basic truths. They are nothing to do with GCMs - or Al Gore or Jim Hansen or anyone else you don't like. I'm sorry if it's difficult to accept but CO2 does absorb IR radiation. It's plainly evident in emission spectra measured from above the earth's atmosphere. " I will not argue. But if the TOA is not in radiatve balance, then the radiation which escapes from the TOA is not solely a function of radiation. It is also a function of conduction, convection, and the latent heat of water. And these factors must be accounted for. I asked for a reference to show that the TOA is in radiative balance. You have no such reference, and the TOA is not in radiative balance. And, therefore, all your nice calculations are so much garbage. Jim. With respect, your above explanation is either a mis-statement or an indication that you've misunderstood the meaning of the term radiation balance and/or some basic physics. "Radiation balance" means radiation out equals radiation in. Myrhe's paper is simply a statement that if the earth were in radiation balance, then doubling CO2 would tend to cause the earth to have a net gain of energy. If the earth were losing energy (due to particular climate cycles) then doubling CO2 might cancel out the effect and bring earth back to balance. Are you confusing radiation balance (when radiation in equals radiation out) with balancing the radiation budget (which would require that we know all sources of radiation in and radiation out)?
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