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and yet you can't prove that can you? I've asked and still you can't explain why that doesn't happen above a desert at night. The hottest places during sunlight and extremely cold when the sunlight is gone. hmmmmmmmm.That is not a belief. That is the definition of back radiation when it is applied to the the GHGs of the atmosphere. Your last sentence is a bit awkward. The earth radiates the full black body spectrum. The GHGs radiate some back to the earth only at their resonance spectra.So you do believe downward radiation is back radiation...downward radiation is just downward radiation...back radiation is radiation absorbed by an object and then emitted back to the object from which it was emitted....
The downward radiation would go down whether there is a detector or not.and the downward radiation was only measured because it was being received by an instrument cooled to a temperature lower than the atmosphere.
Yes radiation doesn't care about direction. So what principle stops back radiation from going to a cooler object if it doesn't care about direction..radiation doesn't care about direction..only that it it is moving always from warm to cool
The entropy of the system of all objects will increase as it should by the second law since during radiation exchange more radiation goes from the hotter objects to the cooler objects. The net radiation imbalance insures the second law is preserved....from less entropy to more entropy...
The atmosphere produces (imperfect) blackbody radiation. It has some elevated GHG spikes but it still resembles the Planck curve. It would still return energy even if it contained no GHGs.
I've asked and still you can't explain why that doesn't happen above a desert at night. The hottest places during sunlight and extremely cold when the sunlight is gone. hmmmmmmmm.
I've asked and still you can't explain why that doesn't happen above a desert at night. The hottest places during sunlight and extremely cold when the sunlight is gone. hmmmmmmmm.
That's easy enough to explain. One of the most potent GHGs is water vapor. That, however, is scarce in desert climates, which is why IR radiation from the desert surface escapes without notably warming up the troposphere, resulting in very low back radiation, which means deserts cool down quickly at night.
dude, I know about water vapor if you've read other threads. But it still doesn't explain the CO2 molecule not working.I've asked and still you can't explain why that doesn't happen above a desert at night. The hottest places during sunlight and extremely cold when the sunlight is gone. hmmmmmmmm.
That's easy enough to explain. One of the most potent GHGs is water vapor. That, however, is scarce in desert climates, which is why IR radiation from the desert surface escapes without notably warming up the troposphere, resulting in very low back radiation, which means deserts cool down quickly at night.
It isn't back radiation...it is the humidity itself heating up as a result of absorbing IR leaving the surface...
dude, I know about water vapor if you've read other threads. But it still doesn't explain the CO2 molecule not working.
I guess my term for warm and yours are two different things. There will still be LWIR leaving the surface, it is much less without the humidity in the air. The sand would freeze if there wasn't some LWIR coming from it.It isn't back radiation...it is the humidity itself heating up as a result of absorbing IR leaving the surface...
And the energy from a warmed up "humidity" at, say, 100 to 500 meters above ground reaches the surface how?
dude, I know about water vapor if you've read other threads. But it still doesn't explain the CO2 molecule not working.
The CO2 molecule is "working", which is why the desert doesn't go into deep freeze upon sunset.
Look, back radiation is combined radiation coming back from all warmed-up GHGs throughout the troposphere. Take one important GHG (water vapor) out, and you get less back radiation, and thus a cooler surface at night.
It isn't back radiation...it is the humidity itself heating up as a result of absorbing IR leaving the surface...
And the energy from a warmed up "humidity" at, say, 100 to 500 meters above ground reaches the surface how?
The CO2 molecule is "working", which is why the desert doesn't go into deep freeze upon sunset.
Look, back radiation is combined radiation coming back from all warmed-up GHGs throughout the troposphere. Take one important GHG (water vapor) out, and you get less back radiation, and thus a cooler surface at night.
Mass markets consumer electronics only measure the amount of, and rate of temperature change in an internal thermopile...
And since the temperature changes only because radiation from a colder object is hitting it, your attempted evasion there makes no sense, and you're still left with your crap theory getting debunked.
I'm not sure what you mean by "very few interactions". The earth radiates in the far IR. N2 and O2 are transparent to that IR. It seems that if it were black body radiation in the IR it could only be through the GHGs. Another way of looking at it is that the emissivity of N2 and O2 is near zero in the IR, whereas the emissivity of the GHGs are high in parts of that region. That's what makes them GHGs. Also I don't think that black body radiation is a term that can be used casually in simple gasses. There are very few vibrational states. There are almost a continuum of vibrational states in a solid because the neighboring atoms are intimately coupled. That coupling promotes a flatter emisivity curve as a function of wavelength which in turn promotes truer BB radiation only for solids or liquids.
Idiot....the temperature change resulting from measuring a cooler object is due to the thermopile cooling off at a faster rate...not because energy from the cool object is radiating to the thermopile...
Idiot....the temperature change resulting from measuring a cooler object is due to the thermopile cooling off at a faster rate...not because energy from the cool object is radiating to the thermopile...
According to your stupid theory, everything colder than the detector should display the same "shade", since the thermopiles "reject" all radiation from any colder object. Whether it's a 1 degree or 100 degree difference, your theory doesn't differentiate. It's colder, so the photons don't get absorbed.
Yet that doesn't happen. We see different "shades" of cold on the output of the thermal scanner. The thermopiles are very clearly absorbing different amounts of energy from cold objects that are different temperatures.
Hence, your theory fails.
Oh, that wasn't a "conversation" will Dr. Happer. That was some loon writing a crazy letter. Conversations require that both people talk.
And if you want to know the flaw in your brilliant theory there ... "vibrational modes". That's how GHG molecules can store energy. Collisions between molecules rarely result in molecule losing the energy of that vibration.
What the professor is saying is that in other words; insofar as moving energy out of the atmosphere, convection rules....radiation is a bit player of such minute proportions that it hardly rates mention.
I thought I answered the black body aspect in post 379. Happer's comments were answered in the previous post to SSDD.What say you wuwei-? Although Happer's numbers are orders of magnitude different than what I have seen elsewhere, the basic principle agrees. Surface IR warms the atmosphere, the atmosphere sends some energy back by blackbody radiation (which was not discussed)
What the professor is saying is that in other words; insofar as moving energy out of the atmosphere, convection rules....radiation is a bit player of such minute proportions that it hardly rates mention.
The professor is right for the one narrow aspect of it he covered. Yes, a CO2 molecule will probably loose its excited vibration state through a collision rather than an emission.
What the professor didn't cover is the equipartition theorem as it involves the energy states of CO2 and H2O and other GHGs. For a simple explanation see
http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic/eqpar.html
There will be equal amounts of energy divided among all the GHG vibration states, rotation states and kinetic energy. Most of the vibration states as shown in the animation will arise from the churning energy of the atmospheric molecules hitting the GHGs and not from the earth's upward LWIR. The upward IR will increase the population of the GHG vibration part of the total energy, and that energy will dissipate through collisions and some LWIR in arbitrary directions.
One way of looking at it is that CO2 can absorb IR, but CO2 excited by collisions will emit most of the IR.
In short, the animation shows a single CO2 molecule absorbing IR and emitting the same energy. In reality an large statistical ensemble CO2 molecules will absorb IR and the statistical ensemble will emit IR, although an individual molecule most likely won't do both in a small time window. Remember through the equipartition theorm there is a tremendous amount of energy in the vibrational states that scatter the LWIR.
I thought I answered the black body aspect in post 379. Happer's comments were answered in the previous post to SSDD.What say you wuwei-? Although Happer's numbers are orders of magnitude different than what I have seen elsewhere, the basic principle agrees. Surface IR warms the atmosphere, the atmosphere sends some energy back by blackbody radiation (which was not discussed)
I don't see a problem. The energies of the various gases will still be partitioned equally. At lower temperatures there will still be equal amounts of energies in each degree of freedom, but of course the energies will be lower.I don't have time to look at your link right now but the problem with the equipartition theory is that there is a temperature gradient to the atmosphere. The type and the quantities coming out of the top are different than what is going in at the surface.
I believe that a gas will radiate according to it's temperature. A higher rate of collisions will keep the vibration states more strongly populated.I re-read 379. I did not realize that you don't believe that objects made of gas, or objects made up of a single element or molecule were exempt from the law that every object emits radiation according to its temperature. Interesting.
What say you wuwei-? Although Happer's numbers are orders of magnitude different than what I have seen elsewhere, the basic principle agrees. Surface IR warms the atmosphere, the atmosphere sends some energy back by blackbody radiation (which was not discussed)
What the professor didn't cover is the equipartition theorem as it involves the energy states of CO2 and H2O and other GHGs. For a simple explanation see
Equipartition of Energy
