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Post by ron on Mar 20, 2009 5:55:46 GMT
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Post by socold on Mar 21, 2009 15:43:23 GMT
I said I wasn't looking for your guesses socold. I asked if you can find anything at all in the way of a scientific study that suggests any of those premises are false. And it isn't clear what period of time you are talking about, I picked a hypothetical period where ghg rose 10 parts per million and a hypothetical breakdown of sources and uses of CO2. You have come up with nada so far. For papers table 7.1 in AR4 and section 7.3.2.2.1. The references to papers can be found there.
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Post by nautonnier on Mar 21, 2009 17:31:21 GMT
The question I have is where is this heat coming from. Everything the sun emits our direction that is not reflected is absorbed immediately by something and is reemitted. Always has. So as if you say we change the balance causing more heat to be absorbed in the atmosphere once it equals the "normal" temperature of the surface we are back in balance again. Being a US Pacific coast resident, about 3 days a year the water feels warm in relationship to the air. The ground is cold at night and warm during the day. Seems the only potential non-external source of additional heat is through the changing of the globe's albedo so that it absorbs more heat. But why should I get excited about that prospect in view of the north Greenland shore study last year that demonstrated the arctic was ice free about 6,000 years ago indicating the global albedo has fluctuated mightily naturally? In balance the earth absorbs approx 235W/m^2 on average from the sun as shortwave radiation, and matches this by radiating 235W/m^2 of longwave radiation. A proportion of the longwave radiation comes from the atmosphere - each layer in the atmosphere radiates an amount proportional to the 4th power of its temperature (in Kelvin). If you double the amount of CO2 throughout the atmosphere, then some of the radiation (about 4W/m^2 or 2% of the original amount) that would have gone into space and cooled the earth is instead reabsorbed. This imbalance causes a gradual build-up of heat. The balance is restored when the atmosphere is warmed sufficiently to overcome the absorption by the extra CO2. In short, the warming comes from the fact that the earth's ability to keep to a stable temperature by losing energy to space is interrupted. But as the earth warms it emits more radiation to space. The warming stops when the earth recovers its ability to lose the same amount of energy as it is receiving. "If you double the amount of CO2 throughout the atmosphere, then some of the radiation (about 4W/m^2 or 2% of the original amount) that would have gone into space and cooled the earth is instead reabsorbed.
This imbalance causes a gradual build-up of heat. The balance is restored when the atmosphere is warmed sufficiently to overcome the absorption by the extra CO2."
And the reabsorbed IR is reradiated almost immediately. Real experiment for you: Go to a desert area with almost zero humidity - where the daylight temperatures are perhaps >35 oC - measure the surface soil temperature and IR output at midday - measure the surface temperature and IR output at midnight - measure and record the time of the lowest temperature of the soil and the IR output at that time. If you want to be really sophisticated you could measure the CO 2 concentrations and better yet you could even repeat the entire experiment by releasing CO 2 into the atmosphere upwind of your radiation experiment and with the hypothesis that the soil temperature should be warmer with higher CO 2 concentrations and the null hypothesis being that there will be no measurable difference between temperatures and IR in higher atmospheric CO 2 concentrations. As desert areas go from 30 - 40 oC to minus ~2 oC type temperatures as a normal diurnal range. It should be simple to see the changes in IR emitted and received. Desert areas are chosen as they are very low humidity and so no water vapor variables and thus a large diurnal range. Of course this has already been done... If your postulate was true - then the low temperatures should be slowly rising as more heat is emitted back by higher concentration of CO 2 in the atmosphere. They are not. Desert minimum temperatures are not increasing with your " some of the radiation (4W/m^2 or 2% of the original amount) that would have gone into space and cooled the earth is instead reabsorbed" As with most postulates based on maths and basic physics and simple laboratory and computer models - this is simply not happening in the real world. www3.interscience.wiley.com/journal/119876565/abstract?CRETRY=1&SRETRY=0To me this is the converse of the solar theories where the mechanism is not clear - but there IS correlation that appears to be borne out in the real world. In the AGW hypothesis the maths and physics appear to be clear - but there is no correlation with the real world data.
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Post by steve on Mar 22, 2009 19:45:52 GMT
In balance the earth absorbs approx 235W/m^2 on average from the sun as shortwave radiation, and matches this by radiating 235W/m^2 of longwave radiation. A proportion of the longwave radiation comes from the atmosphere - each layer in the atmosphere radiates an amount proportional to the 4th power of its temperature (in Kelvin). If you double the amount of CO2 throughout the atmosphere, then some of the radiation (about 4W/m^2 or 2% of the original amount) that would have gone into space and cooled the earth is instead reabsorbed. This imbalance causes a gradual build-up of heat. The balance is restored when the atmosphere is warmed sufficiently to overcome the absorption by the extra CO2. In short, the warming comes from the fact that the earth's ability to keep to a stable temperature by losing energy to space is interrupted. But as the earth warms it emits more radiation to space. The warming stops when the earth recovers its ability to lose the same amount of energy as it is receiving. "If you double the amount of CO2 throughout the atmosphere, then some of the radiation (about 4W/m^2 or 2% of the original amount) that would have gone into space and cooled the earth is instead reabsorbed.
This imbalance causes a gradual build-up of heat. The balance is restored when the atmosphere is warmed sufficiently to overcome the absorption by the extra CO2."
And the reabsorbed IR is reradiated almost immediately. 99.999% of the time, an excited CO2 atom loses its energy to another molecule through collision. It is not reradiated almost immediately. How slowly? Testable hypothesis please. The link wouldn't work. Can you quote the name, authors, journal and date of the paper so I can google it please.
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Post by nautonnier on Mar 22, 2009 21:42:01 GMT
"If you double the amount of CO2 throughout the atmosphere, then some of the radiation (about 4W/m^2 or 2% of the original amount) that would have gone into space and cooled the earth is instead reabsorbed.
This imbalance causes a gradual build-up of heat. The balance is restored when the atmosphere is warmed sufficiently to overcome the absorption by the extra CO2."
And the reabsorbed IR is reradiated almost immediately. 99.999% of the time, an excited CO2 atom loses its energy to another molecule through collision. It is not reradiated almost immediately. How slowly? Testable hypothesis please. The link wouldn't work. Can you quote the name, authors, journal and date of the paper so I can google it please. "99.999% of the time, an excited CO2 atom loses its energy to another molecule through collision. It is not reradiated almost immediately." You should give a citation that tells that the CO2 gives up its energy almost all the time by collision. You realize of course that if this is true that your argument that the "absorbed" IR returns to the surface is now falsified. An excited O 2 or N 2 molecule will not reradiate an IR photon - it will raise the temperature of the 'volume' of atmosphere it is in and cause convection moving the energy upward.
"How slowly? Testable hypothesis please."It is the AGW hypothesis that the minimum temperatures would slowly increase due to CO 2 forcing. So it is up to you to provide the case. The paper below shows that it does not occur in any case - minimum temperatures are NOT increasing The link works for me - but the paper is: Observed tendencies in maximum and minimum temperatures in Zacatecas, Mexico and possible causes Luis Brito-Castillo 1 3 *, Sara C. Díaz Castro 2, Raúl S. Ulloa Herrera 1 1Centro de Investigaciones Biológicas del Noroeste (CIBNOR), Guaymas, Sonora 85454, México 2Centro de Investigaciones Biológicas del Noroeste (CIBNOR), La Paz, B.C.S. 23090, México 3Universidad de Guadalajara (UdeG-CUCEI), Guadalajara, Jalisco 44430. México
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Post by steve on Mar 23, 2009 10:18:40 GMT
99.999% of the time, an excited CO2 atom loses its energy to another molecule through collision. It is not reradiated almost immediately. How slowly? Testable hypothesis please. The link wouldn't work. Can you quote the name, authors, journal and date of the paper so I can google it please. "99.999% of the time, an excited CO2 atom loses its energy to another molecule through collision. It is not reradiated almost immediately." You should give a citation that tells that the CO2 gives up its energy almost all the time by collision. You realize of course that if this is true that your argument that the "absorbed" IR returns to the surface is now falsified. An excited O 2 or N 2 molecule will not reradiate an IR photon - it will raise the temperature of the 'volume' of atmosphere it is in and cause convection moving the energy upward. I guessed that you never read my posts. It is not my "argument that the absorbed IR returns to the surface". It is my argument that the energy imbalance introduced will cause an increase in heat content until the warning results in the outgoing longwave to increase to a level where balance is restored. [/i] It is the AGW hypothesis that the minimum temperatures would slowly increase due to CO 2 forcing. So it is up to you to provide the case. The paper below shows that it does not occur in any case - minimum temperatures are NOT increasing The link works for me - but the paper is: Observed tendencies in maximum and minimum temperatures in Zacatecas, Mexico and possible causes Luis Brito-Castillo 1 3 *, Sara C. Díaz Castro 2, Raúl S. Ulloa Herrera 1 1Centro de Investigaciones Biológicas del Noroeste (CIBNOR), Guaymas, Sonora 85454, México 2Centro de Investigaciones Biológicas del Noroeste (CIBNOR), La Paz, B.C.S. 23090, México 3Universidad de Guadalajara (UdeG-CUCEI), Guadalajara, Jalisco 44430. México [/quote] The link worked when I removed the "?CRETRY=1&SRETRY=0" from it! As the abstract states, a number of sites do demonstrate a reduction in diurnal temperature range, but in this location, the authors say there are measurable influences due to changes in large scale weather patterns that may act in opposition to this change. In other words this is part of the careful measurement of the planet that should refine the understanding of the impact rather than any sort of refutation of the influence of CO2.
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