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Post by radiant on Sept 6, 2009 11:40:31 GMT
I am hoping to collect some studies that show the amount of warming of our atmosphere that is possible via C02 using experiments.
I am interested in any experiment that shows C02 can warm our atmosphere or any that show it can cool it if such studies exist.
Studies showing no change are also ok.
Studies can be done in laboratories or aircraft hangers or in nature or anywhere an experiment can be performed. A experiment can be entirelly observational rather than one that manipulates conditions - eg for various humidities the amount of cooling at night on clear nights was observed.
As a beginning point even simple studies that show warming of simple enclosed atmospheres in lab conditions is the kind of thing i am looking for. Once i have one of those i can then move onto something a bit more sophisticated.
I will then add the studies into this header in order of simplest experiments first.
So far i have no studies.
I am not interesting in any report that makes assumptions or models nature in a theoretical manner. I just want to collect some reports that show what was observed in testable conditions where variables were analysed to show what conditions were present.
What i am looking for is some kind of experiment were either cooling was observed without new heating applied or where constant heat at one end of the experiment was transmitted to the other end of the experiment to be radiated out so that equilibrium was established with temperatures of the atmosphere between being recorded for various gas water mixtures.
Or whatever tests could be devised that can test the influence of c02 to warm our atmosphere which reflect real world situations so we can read about the methods used
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Post by Purinoli on Sept 6, 2009 13:45:04 GMT
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Post by radiant on Sept 6, 2009 15:24:53 GMT
Barretts paper seems to amount to an opinion piece that then created other opinions. Really i am looking for something that says 'we put this heat in and we got this heat out for different gas mixtures', or we observed this night time cooling with these measured gas mixtures in these conditions of no observed atmospheric mixing between altitudes - ie a temperature inversion separated the low air from the upper atmosphere so we could quantify the heat retaining ability of the trace gas C02 in the atmosphere. That sort of thing. I am assuming there must be sufficient C02 in our atmosphere to get measureable changes in temperature via experimentation so that when water content is varied the remaining heat retention can be attributed to the other gases of which C02 is the main gas after water vapour.
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Post by pochas on Sept 6, 2009 16:20:31 GMT
You should not conclude from the following that there is no such thing as "anthropogenic global warming," but since you asked.... Here's the paper by Gerlich and Tscheuschner xxx.lanl.gov/PS_cache/arxiv/pdf/0707/0707.1161v2.pdfSee especially Sec 2.5 page 32 "Experiment by Wood" Also, over on "Niche Modeling" there was some experimentation done. Niche Modeling » Home Science Experiment Disproves Global Warming Theory
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Post by jimcripwell on Sept 6, 2009 16:54:51 GMT
I have been asking the following sort of question for over 3 years on all sorts of different forums. Something like
How do you do an experiment whereby you add CO2 into the atmosphere at current levels, and then measure how much the global temperature rises?
glc tells me I am being silly. In the end, on just about every occasion I have raised the question, people agree that the experiment cannot be done with current technology.
The problem with your approach is that the way the atmosphere works, is just about chaotic. So unless you use the real atrmopshere, in real time, any experiment is useless. And these conditions cannot be met with current technology.
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Post by pochas on Sept 6, 2009 17:26:12 GMT
jimcripwell: "How do you do an experiment whereby you add CO2 into the atmosphere at current levels, and then measure how much the global temperature rises?"
Any experiment you try with a closed container with walls transparent to IR will be defeated by convection. Your results will depend on where you put your thermometer. It may be that convection defeats AGW in the real atmosphere, too.
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Post by donmartin on Sept 6, 2009 18:10:02 GMT
Rather than publishing intellectually inaccessible articles such as the john-daly above, it might be better to employ the resources at hand - some of which are found in the chemistry and physics of other planets - particularly Mars of which the atmosphere is comprised of 95% CO2.
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Post by radiant on Sept 6, 2009 18:28:12 GMT
I have been asking the following sort of question for over 3 years on all sorts of different forums. Something like How do you do an experiment whereby you add CO2 into the atmosphere at current levels, and then measure how much the global temperature rises? glc tells me I am being silly. In the end, on just about every occasion I have raised the question, people agree that the experiment cannot be done with current technology. The problem with your approach is that the way the atmosphere works, is just about chaotic. So unless you use the real atrmopshere, in real time, any experiment is useless. And these conditions cannot be met with current technology. I think you are making the initial experiments required overly complicated. Instead we need to start at the basic level and then get as complicated as we need to do. By common observation the ability of water vapour to retain heat in the atmosphere is relatively quite large because even simple observations with a thermometer must show that heat is retained around the earths surface at night more easily when the humidity is high as compared to when it is low. If C02 is a significant greenhouse gas in the low concentrations present on earth then its ability to retain heat when water is absent must be easily testable in laboratory conditions. The experiments can be quite simple i think. For example a metal mass is precisely warmed in one end of a vacuum lined glass cylinder or Dewer flask into which it is possible to place various test atmospheres. The stopper of the dewer flask is so designed that heat can be easily radiated thru it to a constantly warmed/cooled material. The heating of the mass is then disconnected and the mass and atmosphere is allowed to cool only by whatever heat can escape via the stopper which is by design principally radiation rather than conduction. You would expect cooling of the mass to occur by a combination of 1.radiation and 2. convection or heat transfer to the atmosphere. As a testable variable, radiation would be slowed down by whatever ability the atmosphere had to absorb the heat radiated by the mass or atmosphere before it passed thru the stopper. If there was no atmosphere present in the cylinder you would know how quickly it would cool via radiation only and give the atmospheric thermometers some kind of calibration to allow for this radiation or quantify how it influenced the temperatures recorded. You could then play around with various atmospheres and see how the atmospheres got hotter and how this heat delayed the cooling of the mass. We know that water can create a significant thermal blanket to slow down the radiation of heat. If C02 is significant it will surely be measureable. If this beginning experiment shows C02 is significant then you can begin to think about more sophisticated tests. If C02 is not significant at atmospheric concentrations then tests could be done over a much more concentrated range to produce graphs showing that concentration versus cooling time.
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Post by northsphinx on Sept 6, 2009 18:56:46 GMT
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Post by radiant on Sept 6, 2009 19:13:58 GMT
Haha! Classic! ;D Wood 1909 shows a rock salt (NaCl) greenhouse which has no radiative or thermal greenhouse properties gets as hot as a glass one with such properties because it prevents the hot air inside the greenhouse from mixing with the cold air outside the green house! ;D such an experiment was realized as early as 1909 by Wood [112{115]: \There appears to be a widespread belief that the comparatively high temperature produced within a closed space covered with glass, and exposed to solar radiation, results from a transformation of wave-length, that is, that the heat waves from the Sun, which are able to penetrate the glass, fall upon the walls of the enclosure and raise its temperature: the heat energy is re-emitted by the walls in the form of much longer waves, which are unable to penetrate the glass, the greenhouse acting as a radiation trap. I have always felt some doubt as to whether this action played any very large part 10A problem familiar to those who are involved in PC hardware problems. Falsication Of The Atmospheric CO2 Greenhouse Eects : : : 33 in the elevation of temperature. It appeared much more probable that the part played by the glass was the prevention of the escape of the warm air heated by the ground within the enclosure. If we open the doors of a greenhouse on a cold and windy day, the trapping of radiation appears to lose much of its ecacy. As a matter of fact I am of the opinion that a greenhouse made of a glass transparent to waves of every possible length would show a temperature nearly, if not quite, as high as that observed in a glass house. The transparent screen allows the solar radiation to warm the ground, and the ground in turn warms the air, but only the limited amount within the enclosure. In the \open", the ground is continually brought into contact with cold air by convection currents. To test the matter I constructed two enclosures of dead black cardboard, one covered with a glass plate, the other with a plate of rock-salt of equal thickness. The bulb of a thermometer was inserted in each enclosure and the whole packed in cotton, with the exception of the transparent plates which were exposed. When exposed to sunlight the temperature rose gradually to 65 C, the enclosure covered with the salt plate keeping a little ahead of the other, owing to the fact that it transmitted the longer waves from the Sun, which were stopped by the glass. In order to eliminate this action the sunlight was rst passed through a glass plate. There was now scarcely a dierence of one degree between the temperatures of the two enclosures. The maximum temperature reached was about 55 C. From what we know about the distribution of energy in the spectrum of the radiation emitted by a body at 55 C, it is clear that the rock-salt plate is capable of transmitting practically all of it, while the glass plate stops it entirely. This shows us that the loss of temperature of the ground by radiation is very small in comparison to the loss by convection, in other words that we gain very little from the circumstance that the radiation is trapped. Is it therefore necessary to pay attention to trapped radiation in deducing the temperature of a planet as aected by its atmosphere? The solar rays penetrate the atmosphere, warm the ground which in turn warms the atmosphere by contact and by convection currents. The heat received is thus stored up in the atmosphere, remaining there on account of the very low radiating power of a gas. It seems to me very doubtful if the atmosphere is warmed to any great extent by absorbing the radiation from the ground, even under the most favourable conditions. I do not pretend to have gone very deeply into the matter, and publish this note merely to draw attention to the fact that trapped radiation appears to play but a very small part in the actual cases with which we are familiar."
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Post by glc on Sept 6, 2009 19:58:13 GMT
I am hoping to collect some studies that show the amount of warming of our atmosphere that is possible via C02 using experiments.Can we take it that you accept that CO2 does interact with LW IR radiation at wavelengths in the range of 13-17 micron. The studies showing this effect go back to John Tyndall in the 19th century. It is an effect that will be routinely observed by any scientist with a background in analytical chemistry and IR spectroscopy. Can we also agree that without the 'greenhouse effect' we have a conundrum, i.e. the earth is much warmer than it should given the amount of insolation it receives. Bearing these points in my mind, now consider the following emission spectrum graph www.barrettbellamyclimate.com/page15.htmThis is based on actual satellite observations. Now look at the this plot which is the result of a MODTRAN run. www.barrettbellamyclimate.com/page16.htm This is not to show that validity of MODTRAN, but to provide a clearer explanation of what the plot means. The CO2 'funnel' shows that IR is emitted from much higher in the atmosphere (temp at ~220k). The wavenumber along the x-axis is the reciprocal of the wavelength. A wavenumber of 600 represents a wavelength of ~16 micron; a wavenumber of 760 represents a wavelength of ~13 micron.
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Post by icefisher on Sept 6, 2009 20:37:56 GMT
Can we also agree that without the 'greenhouse effect' we have a conundrum, i.e. the earth is much warmer than it should given the amount of insolation it receives. I would suggest it remains a conundrum even though we have a theory. As I pointed out in another thread, knowing that GHG is a likely contributor to the planet being warmer doesn't then lead directly to the conclusion it is the sole contributor.
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Post by radiant on Sept 6, 2009 20:44:11 GMT
I am hoping to collect some studies that show the amount of warming of our atmosphere that is possible via C02 using experiments.Can we take it that you accept that CO2 does interact with LW IR radiation at wavelengths in the range of 13-17 micron. The studies showing this effect go back to John Tyndall in the 19th century. It is an effect that will be routinely observed by any scientist with a background in analytical chemistry and IR spectroscopy. Can we also agree that without the 'greenhouse effect' we have a conundrum, i.e. the earth is much warmer than it should given the amount of insolation it receives. Bearing these points in my mind, now consider the following emission spectrum graph www.barrettbellamyclimate.com/page15.htmThis is based on actual satellite observations. Now look at the this plot which is the result of a MODTRAN run. www.barrettbellamyclimate.com/page16.htm This is not to show that validity of MODTRAN, but to provide a clearer explanation of what the plot means. The CO2 'funnel' shows that IR is emitted from much higher in the atmosphere (temp at ~220k). The wavenumber along the x-axis is the reciprocal of the wavelength. A wavenumber of 600 represents a wavelength of ~16 micron; a wavenumber of 760 represents a wavelength of ~13 micron. 1. C02 absorption spectra etc I have no problem with the basic absorption data. The issue for me is what influence a trace gas like c02 can have. And that is the part i am hoping to learn more about by seeing experiments. 2. Green house affect As shown by Wood in 1909 a green house with a transparant (rock salt) material having no ability to restrict wavelengths gets just as hot as a glass greenhouse. I think we can agree our atmosphere does not mix with materials outside the earths region of influence Therefore as in a garden greenhouse earths heat is retained by Woods observation that a gas does not easily emit heat to space once warmed by convection or conduction or absorption or whatever. I have to admit this was news to me but that seems the science of garden greenhouses ie they prevent the gas inside the greenhouse from mixing with cooler air. Our atmosphere might be more complicated but we need to determine that by science in the same manner Wood appears to have done back in 1909 Additionally on what is not an entirelly irrelevant point the earths interior is tremendously hot and is being cooled at the surface by warming the atmosphere and that has to be added to the influence of the suns heating of the earths surface. For example recent melting of the greenland ice cap appears to have stabilised and it appears there may be some kind of internal heating responsible for that activity. Obviously we cannot say the earths surface is a black body being only warmed from outside the earth by as you describe it, insolation. 3 Actual satellite emmission observations. The first link is for what appears to be a single view of one part of the earths surface in 1974. I am not sure how many views that is going by the text. At face value it is interesting however, and shows a dimension to experimental observation i had not considered and need to think about At this point in time i need to read more about what exactly i am observing in these graphs. And by the way please stop the nonesense about thermometers. Thermometers are fine if they are used sensibly. I am arguing that thermometer readings are being taken as gospel recordings of local conditions when demonstrably there are local absurdities that may be influencing the results - something you have dismissed as being irrelevant. It is not about thermometers. It is about correctly using a thermometer and how different thermometers need to be reliably cross referenced to known physical events on earth for calibration for the purposes of giving meaning to a warming claim of only 0.6 degree of change in one century. Please dont tell me it is a massive amount for climate purposes. It is still a tiny amount for a one hundred year old human recorded temperature record in a changing world using many different thermometers at the same location.
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Post by northsphinx on Sept 6, 2009 21:29:42 GMT
Can we take it that you accept that CO2 does interact with LW IR radiation at wavelengths in the range of 13-17 micron. Can we also agree that without the 'greenhouse effect' we have a conundrum, i.e. the earth is much warmer than it should given the amount of insolation it receives. Bearing these points in my mind, now consider the following emission spectrum graph www.barrettbellamyclimate.com/page15.htmThis is based on actual satellite observations. Now look at the this plot which is the result of a MODTRAN run. www.barrettbellamyclimate.com/page16.htm This is not to show that validity of MODTRAN, but to provide a clearer explanation of what the plot means. The CO2 'funnel' shows that IR is emitted from much higher in the atmosphere (temp at ~220k). The wavenumber along the x-axis is the reciprocal of the wavelength. A wavenumber of 600 represents a wavelength of ~16 micron; a wavenumber of 760 represents a wavelength of ~13 micron. Agree glc . BUT and this is the BIG BUT I quote Your last link: "As an example of the temperature interpretation, the region from 800-1000 cm-1 shows that the emission comes from a region with a temperature about 295 K or 22° C. That spectral region forms part of the infrared 'window' where none of the greenhouse gases show appreciable absorption and that radiation originates at the Earth's surface. It may be assumed that 22° C is the temperature of the surface covered by the satellite when recording the spectrum." That is a clear sky IR spectrum over a 22° C surface. It is NOT the earth Spectrum. It is an example of an clear sky situation over a warm surface. Average surface temperature is much lower and there is much more clouds at higher elevations = lower temperature that make the reality much different. The deep CO2 hole will more or less dissapear in the reality due to the high altitude clouds. Here is a picture still with just the vapor, not clouds, just vapor that hide most of CO2 effects. upload.wikimedia.org/wikipedia/commons/7/7c/Atmospheric_Transmission.pngAnd here is a real measurement: ams.allenpress.com/perlserv/?request=display-figures&name=i1520-0442-16-22-3820-f07
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Post by socold on Sept 6, 2009 21:34:03 GMT
I could conceive of a large scale experiment in which a vacuum tube 15 miles long was built, into which was placed a smaller 15 mile long tube which contained a cleverly maintained atmospheric profile of gases, with declining pressure, temperature, varying concentrations of different gases, etc all set up to represent the properties of a 15 mile high column in the atmosphere with plenty of sensors to measure precisely the temperature, pressure, emission, etc at any point.
You could then shine shortwave light radiation through one end to simulate sunlight which would pass through the column and warm the base. The base would then emit IR back through the column. There would be convection due to the temperature gradient.
There would be problems with a lack of horizontal energy transport as there would be no neighboring columns, there would be problems with a lack of IR and visible light coming from an angle, but supposedly they could simulate this once they saw the behavior of a single column.
But then I think, why would anyone bother doing such a big experiment when it can all be accomplished in many smaller steps? Why couldn't scientists instead take 1 meter columns of air in the lab under varying conditions and measure and record all the input/outputs. They could then piece together the behavior of 15 mile column of air knowing the behavior of each 1 meter segment. They could also piece together the interactions of neighboring columns of air.
Well this is what climate science has done. This is why no large scale experiment exists to show co2 causes warming. It's because the sum of the small scale experiments performed provide enough, if not all, of what a large scale experiment would show to make it unnecessary.
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