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Post by sigurdur on Sept 22, 2016 4:35:04 GMT
Other things being equal, the temp of the water won't increase or decrease the rate of evaporation. Where did you get that idea from? Andrew. It is simple physics. Think about your parameters. You are a smart feller.
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Post by Andrew on Sept 22, 2016 4:46:13 GMT
Where did you get that idea from? Andrew. It is simple physics. Think about your parameters. You are a smart feller. Perhaps I am not understanding what you are saying? Ice cold water does not evaporate much compared to almost boiling water. Boiling water is evaporating very rapidly indeed. Are you disputing any of those 3 observations of mine?
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Post by nautonnier on Sept 22, 2016 12:07:57 GMT
What Sun? It is night time and the only photons hitting the surface of the water are infrared. Hence the statement above. If you change the photon frequency (and/or its wavelength) outside the absorption band of water then the photons will travel into the water and eventually their energy will become heat at a greater depth than a few microns in the water blue light appears to travel several hundred meters. It is the shorter wavelengths of light from the Sun that warm the water It does make any difference whatsoever. The water would be colder without the heating that you are claiming is cooling the water. The water must become warmer before evaporation can increase for the same set of conditions of wind, humidity and pressure. There is no mechanism there to increase evaporation to cause the water to become colder when it is heated. Henry's Law "There is no mechanism there to increase evaporation to cause the water to become colder when it is heated." I agree, " the water" is not being heated. The top layer of molecules is receiving sufficient energy for them to escape when they do they take that kinetic energy with them which is called the latent heat of evaporation. Therefore, the average kinetic energy in the remaining water has reduced colloquially the water has become colder.
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Post by nautonnier on Sept 22, 2016 12:13:09 GMT
I seem to remember being here before - with talk of Swamp Coolers.... "An evaporative cooler (also swamp cooler, desert cooler and wet air cooler) is a device that cools air through the evaporation of water. Evaporative cooling differs from typical air conditioning systems which use vapor-compression or absorption refrigeration cycles. Evaporative cooling works by employing water's large enthalpy of vaporization. The temperature of dry air can be dropped significantly through the phase transition of liquid water to water vapor (evaporation), which can cool air using much less energy than refrigeration. In extremely dry climates, evaporative cooling of air has the added benefit of conditioning the air with more moisture for the comfort of building occupants."en.wikipedia.org/wiki/Evaporative_coolerIncident infrared will enhance the cooling effect above.
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Post by sigurdur on Sept 22, 2016 12:17:56 GMT
Andrew. It is simple physics. Think about your parameters. You are a smart feller. Perhaps I am not understanding what you are saying? Ice cold water does not evaporate much compared to almost boiling water. Boiling water is evaporating very rapidly indeed. Are you disputing any of those 3 observations of mine? Nope In reference to boiling water, no matter how much additional heat you apply to the water, the temperature of the water will not rise above 212F, the boiling point.
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Post by sigurdur on Sept 22, 2016 12:53:35 GMT
Can one apply small experiment outcomes to the atmosphere at large?
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Post by duwayne on Sept 22, 2016 14:06:24 GMT
Nautonnier, my goal here is to try to better understand the viewpoints of those like you who believe there is negligible or no greenhouse warming. To that end at the beginning of this thread I reposted your comments on the greenhouse effect from Astro’s thread and then asked you several questions in order to better understand your view. I’ve tried to summarize the key elements of your view below. Don’t get defensive because I am going to accept whatever you say your view is. I just want it in the simplest form possible with particular focus on how it differs from the mainstream view so Ratty and I can understand it. As I understand it you believe the diagram below with the exception of the 2 references to warming is generally accurate, abeit highly simplified, with respect to overall photon transfers (radiation) associated with the so-called greenhouse effect. You believe the portion of photons which are re-emitted from the greenhouse gases and ultimately reach the earth’s water surfaces do not warm the water but actually cool the water. The portion of the photons which strike a solid surface do cause the earth to warm. You believe that since the earth’s surface is 70% water the net effect of greenhouse gases is negligible. (Feedback effects, if any, are outside the scope of this discussion.)
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Post by nautonnier on Sept 22, 2016 14:33:30 GMT
Duwayne Thanks for the summary, some points I would add: * Any land surface that is warmed will of course increase its radiation of infrared (heat) by the 4th power (Stefan/Boltzmann) meaning that there is a negative feedback * Any vegetation that is heated will increase its rate of transpiration effectively cooling the plant (like the swamp cooler) the energy then being carried away as latent heat in the evaporated water molecules * CO2 is a radiative gas whereas N2 and O2 are not. Any heat that is transferred to CO2 molecules once the energy is at sufficient level will (may) result in the radiation of that heat as infrared. (The qualifier there is due to arguments on whether CO2 actually absorbs or scatters infrared photons and whether that in the time the CO2 is excited whether that is in a form that can be transferred to/from kinetic energy by collision) **** Convection any air that is warmed due to collision with 'excited' CO2 molecules will expand (Avogadro and Charles) this will result in convection and the reduction in pressure will result in a drop in temperature (Charles Law) [Effectively, the number of gas molecules in the same volume at a lower pressure is lower therefore the average kinetic energy of the volume will reduce. Hope all that makes sense *** One would have thought with the importance of these issues to the AGW hypothesis that there would be many experiments that demonstrate these effects. Yet people still refer back to the primitive Arrhenius experiments. That makes me think that nobody wants to see the results of modern experiments.
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Post by acidohm on Sept 22, 2016 14:53:37 GMT
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Post by nautonnier on Sept 22, 2016 15:39:40 GMT
This goes back to my point somewhere above that climate scientists and that includes those at NOAA, are not engineers and misuse terms with abandon. Heat does not equal hot. Infrared radiation if it is absorbed by particular molecules may increase their vibration/kinetic energy in which case the molecule has increased in its heat content. However, free infrared radiation is not making anything 'hot'. The less than capable man at NOAA in this case has confused infrared photons with atmospheric temperature. So when humid air rises and the water vapor condenses or freezes the water molecules give up the latent heat of condensation or fusion. That latent heat is radiated and if not absorbed by a radiative gas, it will continue to space. The latent heat of condensation or fusion does not change with location, temperature or pressure it is always the same. So when you look at the GOES satellites and they show huge amounts of infrared that is not high temperature air - that is infrared. Heat is not HOT
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Post by sigurdur on Sept 22, 2016 15:58:17 GMT
He most certainly does!!
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Post by sigurdur on Sept 22, 2016 16:16:22 GMT
H2O vapor is the driver of temperature and climate. CO2 has very different radiation characteristics than H2O vapor.
Does the level of CO2 act like a temperature controller in climate? Paleo evidence would indicate the effect is not immediate for sure. With the long term variables to say it has a long term effect is also questionable.
Is there a cover over earth? No
Does LW radiation distribute warmth and excite other molecules? It would seem so. Does the mass of the atmosphere affect temperature? Yes.
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Post by Andrew on Sept 22, 2016 16:44:19 GMT
It does make any difference whatsoever. The water would be colder without the heating that you are claiming is cooling the water. The water must become warmer before evaporation can increase for the same set of conditions of wind, humidity and pressure. There is no mechanism there to increase evaporation to cause the water to become colder when it is heated. Henry's Law "There is no mechanism there to increase evaporation to cause the water to become colder when it is heated." I agree, " the water" is not being heated. The top layer of molecules is receiving sufficient energy for them to escape when they do they take that kinetic energy with them which is called the latent heat of evaporation. Therefore, the average kinetic energy in the remaining water has reduced colloquially the water has become colder. The water is being heated. You are just talking complete shite and evidently there is no way to reason with you.
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Post by Andrew on Sept 22, 2016 16:46:53 GMT
Perhaps I am not understanding what you are saying? Ice cold water does not evaporate much compared to almost boiling water. Boiling water is evaporating very rapidly indeed. Are you disputing any of those 3 observations of mine? Nope In reference to boiling water, no matter how much additional heat you apply to the water, the temperature of the water will not rise above 212F, the boiling point. I suggest you read about the vapour pressure of water or ask your extension program to explain why water evaporates more when it is warmer.
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Post by sigurdur on Sept 22, 2016 16:49:49 GMT
The body of water is not being heated. Only a few microns in can water be heated via infrared in the CO2 bandwidth. The few microns then evaporates, taking the warmth with it.
Does the rate of evaporation take more heat than the CO2 bandwidth adds? Measurements show that it does at approx 10 degrees N.
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