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Post by Andrew on Mar 10, 2012 9:00:17 GMT
There seems a fair amount of effort going on at this board to dispute the basic idea that the Earth is warmer due to having an atmosphere capable of absorbing and emitting infrared radiation. The overwhelmingly most important greenhouse 'gas' is of course liquid water and the gas of water which are found in great abundance all around the Earth system. Even the driest place on Earth still has 0.25mm of precipital water vapour above the earths surface, where water has a huge ability to absorb radiation from the surface even at such apparantly small concentations. Roy Spencer did an experiment using a simple arrangement of an insulated box where he measured actual temperatures as recorded by an actual thermometer and he did not as claimed here use a radiation thermometer to record the temperature of his plate, or use an IR thermometer that in any way invalidated the results he got. Instead Roy has made his own IR sky thermometer using the same kind of technology that was demonstrated in a catholic church in 1667 when a parabolic mirror was used to focus IR upon a thermometer and show that the presence of ice some distance away cooled the thermometer. Using such methods it was easily possible to measure temperature at a distance and find the sky temperature was usually much colder than the surface and local air temperature. The results clearly show the sky temperature is colder than the near surface atmospheric temperature apart from when a large thunderstorm is directly overhead. It has been claimed here he only got results when he had cloud cover or that he was using an unreliable IR thermometer or just about any old garbage you want to think of to say his results demonstrated nothing The level of scientific ignorance being shown on this board is pretty well beyond belief. It seems like an orchestrated attempt to dispute simple scientific ideas, where no alternative explanations that have any backing at all in Science are being proposed. It appears also that some posters here are the same person who seems to get off in producing garbage to frustrate and confuse.
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Post by icefisher on Mar 10, 2012 12:10:24 GMT
Spencer shows that cloud bottom reflectivity is robust. But he confounds reflection with emission by saying its clouds emitting radiation that keeps the plate warm.
His device is far more sensitive to radiation changes than outside the insulated box because outside the box has a huge amount of access to stored energy in the ground and the surrounding atmosphere.
When clouds fly overhead an alternative path was created for that energy and demonstrated in the early 19th century by Sir John Leslie who used mirrors to reflect dark light.
But cloud reflection is a far different phenomena than absorption and emission by greenhouse gases.
Leslie demonstrated the reflection of dark light but the theory of backradiation has never been demonstrated it has only been hypothesized and really has been of no use other than a device to stir up climate fears.
Reflection drives all visible light photography and no doubt also drives passive IR photography as well at least of cold objects. Everything reflects some light there is no perfect absorber.
But what the local village idiot does not get is even if there is backradiation, its probably overwhelmed by conduction and convection even if it has a net positive warming effect in the first place after consideration of the shading effect of atmosphere IR absorption out of solar incoming.
Sigurdur's link touches on the 3 dimensional absorption field of gases in the atmosphere. With solar incoming being composed of 50% IR atmospheric absorption is via 1366w/m2 50% of the time through 3 dimensional absorption lines matches 341 watts 100% of the time diffused into the atmosphere. Incoming IR shading and IR outgoing absorption should be a wash backradiation or no backradiation. The disk analogy only applies to surface absorption and surface emissions of IR but does not apply to incoming absorption of IR via solar incoming.
Having an atmosphere capable of storing heat has the ability to raise surface temperatures as does the ground under the surface or anything, which is everything, with an emissivity less than 1.0.
Emissivity purely radiation wise is also a wash. But here again its necessary to ignore role of conduction in warming the planet to equilibrium in spite of reflectivity.
For the same reason a silver plate that reflects 98% of incoming radiation the plate still heats to the same temperature as the environment surrounding it is due to conduction (not greenhouse gases).
To make it simple for the village idiot, I am not suggesting anything as an absolute except that it takes a village idiot to believe one can estimate the effect of greenhouse gases by looking at half its effects and ignoring everything else going on in the climate system.
Backradiation as a theory has been handy but it may not exist in favor of a potential driven flow of energy from hot to cold.
Its totally irrelevant if a greenhouse effect exists until one establishes a relevancy for it through a complete system analysis.
Doing otherwise is akin to getting up in the morning sauntering over to the thermometer pasted to the outside glass, watching it for a few minutes, observing the mercury is rapidly rising in the glass tube, and then running hysterically out of the house screaming that the world is coming to an end.
Get a grip!
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Post by Andrew on Mar 10, 2012 13:05:16 GMT
Spencer shows that cloud bottom reflectivity is robust. But he confounds reflection with emission by saying its clouds emitting radiation that keeps the plate warm. His device is far more sensitive to radiation changes than outside the insulated box because outside the box has a huge amount of access to stored energy in the ground and the surrounding atmosphere. When clouds fly overhead an alternative path was created for that energy and demonstrated in the early 19th century by Sir John Leslie who used mirrors to reflect dark light. But cloud reflection is a far different phenomena than absorption and emission by greenhouse gases. Leslie demonstrated the reflection of dark light but the theory of backradiation has never been demonstrated it has only been hypothesized and really has been of no use other than a device to stir up climate fears. Reflection drives all visible light photography and no doubt also drives passive IR photography as well at least of cold objects. Everything reflects some light there is no perfect absorber. But what the local village idiot does not get is even if there is backradiation, its probably overwhelmed by conduction and convection even if it has a net positive warming effect in the first place after consideration of the shading effect of atmosphere IR absorption out of solar incoming. Sigurdur's link touches on the 3 dimensional absorption field of gases in the atmosphere. With solar incoming being composed of 50% IR atmospheric absorption is via 1366w/m2 50% of the time through 3 dimensional absorption lines matches 341 watts 100% of the time diffused into the atmosphere. Incoming IR shading and IR outgoing absorption should be a wash backradiation or no backradiation. The disk analogy only applies to surface absorption and surface emissions of IR but does not apply to incoming absorption of IR via solar incoming. Having an atmosphere capable of storing heat has the ability to raise surface temperatures as does the ground under the surface or anything, which is everything, with an emissivity less than 1.0. Emissivity purely radiation wise is also a wash. But here again its necessary to ignore role of conduction in warming the planet to equilibrium in spite of reflectivity. For the same reason a silver plate that reflects 98% of incoming radiation the plate still heats to the same temperature as the environment surrounding it is due to conduction (not greenhouse gases). To make it simple for the village idiot, I am not suggesting anything as an absolute except that it takes a village idiot to believe one can estimate the effect of greenhouse gases by looking at half its effects and ignoring everything else going on in the climate system. Backradiation as a theory has been handy but it may not exist in favor of a potential driven flow of energy from hot to cold. Its totally irrelevant if a greenhouse effect exists until one establishes a relevancy for it through a complete system analysis.
Doing otherwise is akin to getting up in the morning sauntering over to the thermometer pasted to the outside glass, watching it for a few minutes, observing the mercury is rapidly rising in the glass tube, and then running hysterically out of the house screaming that the world is coming to an end.
Get a grip!
You dont need backradiation to produce a warmer earth if the sky temperature is not the temperature of space You are continually disputing the basic radiation heat loss curves If the sky temperature was not so warm the plants would all be dead by morning
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Post by magellan on Mar 10, 2012 14:09:44 GMT
There seems a fair amount of effort going on at this board to dispute the basic idea that the Earth is warmer due to having an atmosphere capable of absorbing and emitting infrared radiation. The overwhelmingly most important greenhouse 'gas' is of course liquid water and the gas of water which are found in great abundance all around the Earth system. Even the driest place on Earth still has 0.25mm of precipital water vapour above the earths surface, where water has a huge ability to absorb radiation from the surface even at such apparantly small concentations. Roy Spencer did an experiment using a simple arrangement of an insulated box where he measured actual temperatures as recorded by an actual thermometer and he did not as claimed here use a radiation thermometer to record the temperature of his plate, or use an IR thermometer that in any way invalidated the results he got. Instead Roy has made his own IR sky thermometer using the same kind of technology that was demonstrated in a catholic church in 1667 when a parabolic mirror was used to focus IR upon a thermometer and show that the presence of ice some distance away cooled the thermometer. Using such methods it was easily possible to measure temperature at a distance and find the sky temperature was usually much colder than the surface and local air temperature. The results clearly show the sky temperature is colder than the near surface atmospheric temperature apart from when a large thunderstorm is directly overhead. It has been claimed here he only got results when he had cloud cover or that he was using an unreliable IR thermometer or just about any old garbage you want to think of to say his results demonstrated nothing The level of scientific ignorance being shown on this board is pretty well beyond belief. It seems like an orchestrated attempt to dispute simple scientific ideas, where no alternative explanations that have any backing at all in Science are being proposed. It appears also that some posters here are the same person who seems to get off in producing garbage to frustrate and confuse. www.drroyspencer.com/2010/08/help-back-radiation-has-invaded-my-backyard/Well, it is one of the marvels of our electronic age that you can buy a very sensitive handheld IR thermometer for only $50 and observe the effect for yourself. or use an IR thermometer that in any way invalidated the results he got. He used it to validate his hypothesis. In the latter posts of that thread, Anonymous is in a kind way telling Dr. Spencer whatever he thought he was measuring with his IRT was not the GHE. As much respect that I have for Dr. Spencer, his experiment did not validate anything to do with GHG and "back radiation". I am not saying he is wrong on the science, just that his experiment was bunkum. I told you from the start that IRT must be handled with care and one should take the stated accuracies by manufacturers with a grain of salt. See if you can find the problem. www.omega.com/temperature/z/pdf/z063-066.pdfIt's odd though I cannot find the term "back radiation" in any physics text books outside of climate science. Would you be kind enough to find one? Also, I am more interested in you (since you said you are a man of science) debunking the following rather than calling me a *unt, moron or other colorful metaphors. If you can't refute it without going into endless irrelevant psychobabble, don't bother posting it because I at least will not bother reading. principia-scientific.org/publications/New_Concise_Experiment_on_Backradiation.pdfAn example of psychobabble was your attempt at explaining why the desert surface gets warmer than the tropics after incorrectly stating the effects of solar radiation on water at the surface. You had no idea what you were talking about. Hence, I didn't bother replying. Whatever you were measuring on your bricks was not "back radiation". One could note nobody bothered coming here from Spencer's blog in support of your "experiment". Maybe this will put things into perspective on heat content and what actually keeps the land surfaces warm, which you apparently don't have a clue about either.
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Post by Andrew on Mar 10, 2012 14:27:00 GMT
There seems a fair amount of effort going on at this board to dispute the basic idea that the Earth is warmer due to having an atmosphere capable of absorbing and emitting infrared radiation. The overwhelmingly most important greenhouse 'gas' is of course liquid water and the gas of water which are found in great abundance all around the Earth system. Even the driest place on Earth still has 0.25mm of precipital water vapour above the earths surface, where water has a huge ability to absorb radiation from the surface even at such apparantly small concentations. Roy Spencer did an experiment using a simple arrangement of an insulated box where he measured actual temperatures as recorded by an actual thermometer and he did not as claimed here use a radiation thermometer to record the temperature of his plate, or use an IR thermometer that in any way invalidated the results he got. Instead Roy has made his own IR sky thermometer using the same kind of technology that was demonstrated in a catholic church in 1667 when a parabolic mirror was used to focus IR upon a thermometer and show that the presence of ice some distance away cooled the thermometer. Using such methods it was easily possible to measure temperature at a distance and find the sky temperature was usually much colder than the surface and local air temperature. The results clearly show the sky temperature is colder than the near surface atmospheric temperature apart from when a large thunderstorm is directly overhead. It has been claimed here he only got results when he had cloud cover or that he was using an unreliable IR thermometer or just about any old garbage you want to think of to say his results demonstrated nothing The level of scientific ignorance being shown on this board is pretty well beyond belief. It seems like an orchestrated attempt to dispute simple scientific ideas, where no alternative explanations that have any backing at all in Science are being proposed. It appears also that some posters here are the same person who seems to get off in producing garbage to frustrate and confuse. www.drroyspencer.com/2010/08/help-back-radiation-has-invaded-my-backyard/Well, it is one of the marvels of our electronic age that you can buy a very sensitive handheld IR thermometer for only $50 and observe the effect for yourself. or use an IR thermometer that in any way invalidated the results he got. He used it to validate his hypothesis. In the latter posts of that thread, Anonymous is in a kind way telling Dr. Spencer whatever he thought he was measuring with his IRT was not the GHE. As much respect that I have for Dr. Spencer, his experiment did not validate anything to do with GHG and "back radiation". I am not saying he is wrong on the science, just that his experiment was bunkum. See if you can find the problem. www.omega.com/temperature/z/pdf/z063-066.pdfIt's odd though I cannot find the term "back radiation" in any physics text books outside of climate science. Would you be kind enough to find one? Backradiation is not a scientific term. Scientifically all objects emit radiation according to known laws in a manner proportional to temperature For gray bodies the Stefan-Boltzmann Law can be expressed as www.engineeringtoolbox.com/radiation-heat-transfer-d_431.htmlq = å ó T4 A (2) If there are two bodies the net heat loss rate is expressed as q = å ó (Th4 - Tc4) Ac (3) where å = emissivity of the object (one for a black body) ó = 5.6703 10-8 (W/m2K4) - The Stefan-Boltzmann Constant Th = hot body absolute temperature (K) Tc = cold surroundings absolute temperature (K) Ac = area of the object (m2)
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Post by magellan on Mar 10, 2012 14:34:21 GMT
www.drroyspencer.com/2010/08/help-back-radiation-has-invaded-my-backyard/Well, it is one of the marvels of our electronic age that you can buy a very sensitive handheld IR thermometer for only $50 and observe the effect for yourself. or use an IR thermometer that in any way invalidated the results he got. He used it to validate his hypothesis. In the latter posts of that thread, Anonymous is in a kind way telling Dr. Spencer whatever he thought he was measuring with his IRT was not the GHE. As much respect that I have for Dr. Spencer, his experiment did not validate anything to do with GHG and "back radiation". I am not saying he is wrong on the science, just that his experiment was bunkum. See if you can find the problem. www.omega.com/temperature/z/pdf/z063-066.pdfIt's odd though I cannot find the term "back radiation" in any physics text books outside of climate science. Would you be kind enough to find one? Backradiation is not a scientific term. Net Radiation Heat Loss Rate www.engineeringtoolbox.com/radiation-heat-transfer-d_431.htmlIf a hot object is radiating energy to its cooler surroundings the net radiation heat loss rate can be expressed as q = å ó (Th4 - Tc4) Ac (3) where Th = hot body absolute temperature (K) Tc = cold surroundings absolute temperature (K) Ac = area of the object (m2) Yep, psychobabble, just as predicted.
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Post by Andrew on Mar 10, 2012 14:35:25 GMT
Backradiation is not a scientific term. Net Radiation Heat Loss Rate www.engineeringtoolbox.com/radiation-heat-transfer-d_431.htmlIf a hot object is radiating energy to its cooler surroundings the net radiation heat loss rate can be expressed as q = å ó (Th4 - Tc4) Ac (3) where Th = hot body absolute temperature (K) Tc = cold surroundings absolute temperature (K) Ac = area of the object (m2) Yep, psychobabble, just as predicted. Perhaps you prefer this version from "Engineering Physics" books.google.fi/books?id=6C0R1qpAk7EC&pg=SA2-PA423&dq=Tyndall+radiation+platinum+stefan+fourth&hl=en&sa=X&ei=n0NcT-neIIOH4gSy6rHFDw&ved=0CEYQ6AEwBA#v=onepage&q=Tyndall%20radiation%20platinum%20stefan%20fourth&f=false"On the basis of experimental results of Tyndall for radiation emitted by a platinum wire, Joseph Stephan proposed an empirical law which relates the quantity of radiation emitted by a body and its temperature, and is called Stephans law" Energy emitted = ó T 4"Later in 1884, on the basis of pure thermodynamic considerations, Boltzman gave a theoretical proof of Stephans law and showed that the law is strictly applicable to the radiation emitted by a perfect black body" For gray bodies the law becomes Energy emitted = å ó T 4Which for two objects of different temperatures each absorbing radiation from the other leads to a net radiation loss from one to the other of Net energy loss = å ó (Th4 - Tc4) Stephan-Boltzman law was experimentally verified in 1897 by Lummer and Pringsheim.
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Post by Ratty on Mar 11, 2012 22:44:16 GMT
I was going to read this thread until I came across the word "Moron" addressed at another poster.
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Post by sigurdur on Mar 11, 2012 23:03:00 GMT
I was going to read this thread until I came across the word "Moron" addressed at another poster. I agree. I have provided some sense to this, and the name calling turned me off to continue.
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Post by Andrew on Mar 12, 2012 6:11:04 GMT
I was going to read this thread until I came across the word "Moron" addressed at another poster. I agree. I have provided some sense to this, and the name calling turned me off to continue. You were totally unhelpful probably by design. According to Numeruno you are a proven liar. All you did was ensure that chaos continued with your silly claim that ALL objects are cooling. My boiler is for example at this moment getting hotter. What kind of a fool continually says that ALL objects are getting cooler? And then adds to the stupidity by continually refusing to realise that is a stupid thing to say no matter how obvious it must be that the statement is wrong? Probably it is all part of the game of obfuscation you so enjoy playing
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Post by sigurdur on Mar 12, 2012 12:26:02 GMT
iceskater: All objects are cooling.
As far as your comment that I am a liar, that is a direct accusation without any supporting proof from you.
I recommend that you take a break from this board, as your conduct is not benifitting anyone.
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Post by Andrew on Mar 12, 2012 15:54:53 GMT
iceskater: All objects are cooling. As far as your comment that I am a liar, that is a direct accusation without any supporting proof from you. I recommend that you take a break from this board, as your conduct is not benifitting anyone. Objects only cool when they are cooling. We cannot say that all objects are cooling Your statement is incomplete. At this moment in time many objects are not cooling. Do you understand what you are saying or are you just going to endlessly repeat that all objects are cooling?
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Post by sigurdur on Mar 12, 2012 19:21:25 GMT
iceskater: All objects are cooling. This is why they emit radiation.....without a source of heat the cooling would slowly become absolute zero.
This is a central law in physics. I know this is hard to wrap one's brain around, it took me awhile, but once I understood this, it was actually easy to comprehend.
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Post by Andrew on Mar 12, 2012 19:54:32 GMT
iceskater: All objects are cooling. This is why they emit radiation.....without a source of heat the cooling would slowly become absolute zero. This is a central law in physics. I know this is hard to wrap one's brain around, it took me awhile, but once I understood this, it was actually easy to comprehend. You are mixing up ideas and blindly repeating what you think is the gospel truth. If the theories of the Universe are true then it could be true that the temperature of all of the matter in the universe is on average cooling. However some molecules are getting hotter and some are getting colder. At this moment in time a considerable percentage of the universal matter is getting hotter. a tiny fraction of a second later the same matter could be getting colder or back to the same temperature or getting even hotter. You cannot say that all matter is getting colder. There is no central law in physics that supports your opinion on the matter. You are just muddled up.
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Post by sigurdur on Mar 12, 2012 23:37:53 GMT
"If the theories of the Universe are true then it could be true that the temperature of all of the matter in the universe is on average cooling."
Iceskater........you got it. Because of molecular motion, which expends energy, all matter is cooling. When a mass absorbs energy, it warms, as the other object cools. I don't know how much more simply I can explain this. The rate of cooling changes when an object warms. However, the central tenant of radiation laws are that ALL matter emits radiation.....all matter epxends energy, and by this expense of energy it is cooling. The rate of cooling is what can change......but not the central law of energy.
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