Note: This is a contentious subject, and I have often shied away from it because it often erupts in food fights. However, Mr. Gill is making a good-faith effort here, and asks some relevant questions that I consider worth discussing. His original essay was sans graphics, and I’ve added two relevant graphics to aid in the discussion. – Anthony
Do Wien’s Law and Quantum Physics 101 prove CO2 can’t warm anything?
Guest essay by Rod Gill
WUWT has happily demonstrated many ways CO2 fails to produce measurable warming. I’ve thought of another way. It’s so simple I must have missed something, but I simply can’t work out what. It goes like this…
Experts suggest there is a net down welling 2W/m2 of long wave infra-red radiation (LWIR) that is causing global warming. I suggest the quality of that 2W of radiation is crucial to determining whether or not it causes any atmospheric warming at all. First a few key points which I think are facts and not open to dispute.
My understanding of Thermodynamics and Radiation from CO2 is as follows:
In Thermodynamics, Temperature is the average kinetic energy of the particles in a body (solid or gas).
The temperature of a volume of air has nothing to do with the amount of radiation (sometimes mislabelled as heat by scientists) passing through it. Unless that radiation is at a frequency that can be absorbed by the air, its temperature is completely unaffected by the radiation (ignoring any convectional heating).For example at the top of Mount Everest, there is a lot of solar energy (long and short wave radiation) there when the sun is out but the temperature is still cold.
Different gases have different emission spectrums. For example Oxygen and Nitrogen do not absorb or emit Long Wave Infrared Radiation (LWIR) at all, so are not considered to be “Greenhouse” gases.
The temperature of a body (gas, liquid or solid) directly affects the wavelength of the radiation it emits and absorbs.
Wien’s Law defines the temperature – wave length relationship. The formula is Temperature (in degrees Kelvin) = 2898 / peak wave length in µm (micro metres). So for the average temperature of the Earth, lets call it 15C (=289 Kelvin), the wave length is 2898 / (15+274) = 2898 ÷ 289 = 10um.
The wavelength of the peak of the blackbody radiation curve decreases in a linear fashion as the temperature is increased (Wien’s displacement law). This linear variation is not evident in this kind of plot since the intensity increases with the fourth power of the temperature (Stefan- Boltzmann law). The nature of the peak wavelength change is made more evident by plotting the fourth root of the intensity. Source: http://hyperphysics.phy-astr.gsu.edu/hbase/wien.html
Carbon Dioxide’s absorption spectrum shows it absorbs LWIR at three different narrow wave lengths, sometimes called finger frequencies. Two of those wave lengths happen at temperatures too hot to exist in the atmosphere, the remaining wave length is 15um.
15um equates to 2898 ÷ 15 = 193K = -80C or -122F. In the atmosphere this temperature only occurs about 90-100Km high in the atmosphere.
Carbon Dioxide only emits and absorbs radiation at -80C from a narrow layer of atmosphere 90Km above the Earth’s surface.
So now we need to examine the quality of that 15um radiation and its ability to heat the lower atmosphere. To do this we need to understand basic Quantum Physics as taught in 101 classes to Physics and Engineering students at University. Confession: I’m an Engineer, but trained before Quantum Physics was introduced to University courses so I’m self-taught, hence my need for a sanity check. Which, dear reader, is where you come in.
The key points in basic Quantum Physics, regarding radiative heat transfer, are:
Molecules have one or more electrons circling them. Their orbital height is not variable, But fixed. The electrons only orbit at set altitudes, the closer to the molecule the lower the kinetic energy of the molecule and so the lower the molecule’s temperature.
For a molecule to “warm up” (have more kinetic energy) it needs its electrons to move to a higher, more energetic orbit. This can happen in one of two ways, get energy from a more energetic molecule via collision or receive energy via radiation.
For an electron to move to a higher orbit from radiation it must receive a photon with sufficient energy for an electron to reach that higher orbit.
Photons with too much energy raise the electron to the higher orbit then the molecule immediately re-radiates surplus energy.
Photons with not enough energy to raise the orbit of any of the electrons are either scattered or immediately re-radiated (effectively reflecting or scattering them) with no change to the molecule’s kinetic energy, or temperature.
The Photon must have a frequency that resonates with the molecule, otherwise the Photon is just scattered or reflected immediately with no temperature change to the molecule.
Carbon dioxide can only absorb Long Wave Infrared Radiation (LWIR) energy and radiate it at 15 micro metres, a fraction of the LWR spectrum.
Electrons orbiting molecules of a liquid or solid need more energy to boost an electron’s orbit than electrons in a gas, so require more energetic photons again to warm them.
Therefore it is my understanding that it is impossible for the LWIR emitted by a cold low energy CO2 molecule to have the energy required to warm any molecule in the atmosphere warmer than -80C and certainly no molecule in a liquid (EG water) or a solid body, as their electrons require even more energy.
LWIR from CO2 simply bounces around the atmosphere until it escapes into space and it causes no warming of the lower atmosphere at all. The energy level of that 2W of LWIR is too poor to have any affect. It needs to be closer to 10um to be energetic enough to warm anything.
So the idea of CO2 trapping heat in the atmosphere is all wrong. Yes LWIR from CO2 is retained in the atmosphere longer, but it simply bounces around until it escapes into space without causing any warming.
So am I right? I deliberately have not included any references because I want you to confirm or deny my understanding independently. If I gave you my references, which knowing the web may or may not be accurate, you might erroneously come to the same conclusions I have. However I have tried to limit my research to University papers and lecture notes hoping they are more reliable.
If I’ve got this right, CO2 caused global warming isn’t possible. If I haven’t got this right, then exactly how does LWIR radiated from CO2 warm anything?
Many thanks and please limit comments to specifics mentioned above. And if you disagree with the science above, please explain which sentences you disagree with and exactly how, at the Quantum Physics level, photons from a CO2 molecule at -80C can warm anything.
I am not disagreeing with anything (yet). But I would like to make a few comments before all and sundry jump in:
Photon s are NOT real massless particles. The concept of a photon is a human construct from our mind in an attempt to observe the apparent “lumpiness” of certain phenomena with electro-magnetic radiation.
E-M Radiation CANNOT be directly observed, you can only observe the effect on real matter, and we know real matter is “lumpy” (particles). It MAY be the case that e-m radiation is not in any way “quantised” but is purely analogue and only the effects seem to suggest quantisation hence the concept of the photon.
Try, if possible, making your arguments work BOTH for photons (quantised e-m lumps) and also for e-m which is not quantised. You may need 2 completely different arguments. I suggest the results of doing this will (or may be) illuminating (pun intended).
My final comment is that the understanding of this, i.e. RADIATION, as it applies in the real world is THE most important thing we need to grasp in considering CAGW. and if we cannot grasp it correctly and securely by logical argument then let’s have some suggestions from you for REAL WORLD EXPERIMENTS to settle the issue(s).
Bloke down the pub
November 19, 2017 6:41 am
‘Their orbital height is not variable, But fixed. The electrons only orbit at set altitudes, the closer to the molecule the lower the kinetic energy of the molecule and so the lower the molecule’s temperature.’
The closer to the nucleus?
DR
November 19, 2017 6:41 am
Ah, the upside down greenhouse effect. Things haven’t panned out quite the way it was explained ~30 years ago using basic high school physics as we’re constantly reminded. http://1clickurl.com/XYwCjxT
A “good-faith effort” indeed, but, IMHO, Rod Gill misapplies the equations he uses and misinterprets the results. Satellite views of long wave radiation from Earth to Space, looking down, and views of long radiation from Space to Earth, looking up from the surface, show the actual warming effects of water vapor, CO2, and other “greenhouse” gases.
Rob
November 19, 2017 6:46 am
I’ve never heard a weather forecast yet that said, it’s going to be a high CO2 night, which is expected to keep temperatures warmer. They always say, lots of cloud cover tonight will help keep temperatures warmer, or the lack of cloud cover tonight will see temperatures plunge. If CO2 makes temperatures warmer, then we here in middle Alberta have been shortchanged for the last three weeks. So I don’t disagree with anything you say.
Nylo
November 19, 2017 6:53 am
Carbon Dioxide only emits and absorbs radiation at -80C from a narrow layer of atmosphere 90Km above the Earth’s surface.
Why do you say that? Things do not emit radiation ONLY at their peak wavelength. They emit at that wavelength and also at others.
DaveKeys
November 19, 2017 6:54 am
Does beg the question how much energy in the wavelength that CO2 absorbs is reflected back towards space. This will tell us the maximum possible amount of heat that CO2 can trap.
It will not stop warmists as CO2 will cause a positive feedback loop that increases H20 in the atmosphere.
But as H2O increases so the energy available to warm CO2 will therefore decrease.
How do I feel that this green house theory is not fully explained.
There IS a greenhouse gas effect. Here’s an example.
Let the flux from the sun to the ground be 4 joules/unit time*unit
area,
and stay constant.
–> SUN
–>
–>
–>
–>
With no greenhouse gases, the earth will either heat up or cool down
until
the outgoing flux from the earth is equal to the incoming flux from
the sun.
Sun –> O O O O <– <– <–O O–> <–
You've now got an unbalanced situation where 5 joules/unit time*unit
area
are hitting the earth, 4 from the sun and half of the 2 from the
atmosphere,
and only 3 joules per second are leaving the earth, the 2 not
absorbed by
the gas, and half of the 2 from the atmosphere. The atmosphere will
gradually
warm up until outgoing flux from the atmosphere, plus the fraction of
the flux from the
earth not intercepted by the atmosphere, equals the incoming amount
from the sun.
Since in my example, half of the outgong flux is intercepted by the
atmosphere,
the watts hitting the earth's surface will increase to
Remember the atmosphere is intercepting half of this, so 16/6 joules
(unit time*unit area)
is intercepted by the greenhouse gas atmosphere, and another half,
16/6 joules, escapes
directly to space.
The final equilibrium balance is
16/12 Earth
O–>16/12 16/12(from atmosphere)–>Earth
Sun –>4
16/6 to atmosphere <–
Earth
16/6 to space <–
Earth
So yes, a greenhouse gas will warm the earth, the amount of warming
depends on the fraction
of the outgoing (and incoming for that matter) radiation absorbed by
the atmosphere.
………………………………………………..
If the atmosphere was absorbing ALL radiation from the sun , you'd get a final balance of
4 watts/unit area from sun to atmosphere and 4 watts from atmosphere to space- in balance
4 watts from sun to atmosphere, 4 watts from earth's surface to atmosphere
4 watts from atmosphere to space, 4 watts from atmosphere to earth surface- in balance
4 watts from atmosphere to earth surface, 4 watts from earth surface to atmosphere – in balance.
So an atmosphere that absorbed ALL solar radiation would have a net zero greenhouse effect.
……………………………………………………….
When you look at the blackbody radiation curve, you'll notice that the shortwave frequencies, not affected by CO2, increase at a much greater rate with increasing temperature than longer wave radiation, which IS affected by the amount of CO2 in the air. The net result is that increasing absorption of long wave radiation by CO2 is MUCH smaller than increases in surface temperature. In addition, as the atmosphere warms up, a larger fraction of the sun's incoming radiation is absorbed directly by the atmosphere, reducing the overall greenhouse effect.
John
November 19, 2017 7:06 am
I agree with your findings, but not for the same reasons. Retired now, I used to be a laser engineer, and instrument design engineer, including weather stations, and all manner of energy measuring devices. I created infrared measurement systems and laser energy measurement systems. Thus, I know a little about gas behavior and thermal characteristics.
So, my argument against CO2 ‘warming’ anything goes like this? If it DID increase the surface temperature, the surface would radiate to space at the 4th power of the increase, instantly cooling itself back down. We know that everything radiates and we have laws for quantifying it.
Experiment: Try to heat a stove with a flashlight. There are lots of photons, you can see them. Yet the stove does not warm. Why? Because for each photon that strikes the stove, the stove emits millions, maybe billions of photons itself. Those few photons from the flashlight are simply overwhelmed, and the result is immeasurable. Applying that to CO2, how many surface molecules radiate for every CO2 molecule? There is NO WAY there is sufficient energy in CO2 radiation from the atmosphere to increase surface temperature, because the surface radiates FAR more than the CO2 does. And, again, if the CO2 DID somehow manage to ‘warm’ the surface, it’s millions of molecules per CO2 molecule would simply radiate at a higher rate instantaneously, and ‘cool’ back to equilibrium.
Lastly, consider that if there were CO2 ‘radiation’, it would cast a shadow when blocked – an invisible one, but still a shadow. If you create a filter that can filter out the CO2 spectrum, and place it on the window of an infrared thermometer, with another identical thermometer without the filter, you will find that they both measure the same temperature. That would not be possible, if CO2 was indeed ‘heating’ anything, those two thermometers would have to read differently.
I will not start arguiing about the physical phenomenon in a GH molecule, when a photon with the right wavelenght / frequency hits this molecule. This is a very basic stuff of molecular physics and there is enough evidence in which way it happnes. But I do not agree with the description of Rod Gill.
The GH effect in the atmosphere is a fact and it is caused by GH gases: H2O 81 %, CO2 13 %, O3 4 % CH4 & N2O 1 %, clouds 1 %. Link: http://www.sciencedomain.org/abstract/17484
Here is a figure from my web site, which shows the absorption wavelenghts of GH gases. A very bsic thing is that the absorption wavelenghts of other GH gases overlaps with water making them rather weak:
One thing more. The Earth’s surface emits about 395 W/m2 in 15 degrees and the LW radition emitted by the atmosphere to space is about 239 W/m2. The radiation loss is 396 – 239 = 157 W/2. Energy does not disappear but it can change its form. The radiation flux of 157 W/m2 maintains the temperature profile of the atmosphere together with the SW radiation absorpbed by the atmosphere, which is about 71 W/2.
A nice essay, I don’t fully understand quantum physics, you have a much greater knowledge of this than me. Could I ask though there is a theory, I am not sure it is conclusive, that as CO2 concentration rises in the atmosphere, the increase in temperature is not linear, but logarithmic. If it is true how would this tie in with your theory? I have pasted my source below which is over 8 years old. https://wattsupwiththat.com/2010/03/08/the-logarithmic-effect-of-carbon-dioxide/
Har-old
November 19, 2017 7:14 am
Whatever the theory, CO2 obviously does not cause actual warming by experiment in the real atmosphere. The increase in CO2 in the ca. one hundred years from near 300PPM to near 400PPM does not correlate with global warming, or some would say, lack thereof.
joshv
November 19, 2017 7:17 am
You’ve got the physics wrong. Absorption spectra have little to do with electrons, and a lot to do with vibration modes of the CO2 molecule. CO2 is a complex molecule. It can move (translation), rotate, and vibrate. A molecule’s energy is equally partitioned between all of these degrees of freedom. The rotational and translational degrees of freedom cannot absorb IR, but the vibration degree of freedom can. The energy from IR, once absorbed by resonance with a vibrational mode, can then be distributed to the other modes. It does not stay ‘locked up’ in vibration, it can cause the molecule to rotate, and to move faster (heat up).
Think of a bunch of molecules bouncing around off of each other, in a collision, one molecule could easily lose much of it’s vibration or rotation and cause the second molecule to bounce off faster in another direction. Over many collisions, the vibrational energy from IR absorbance will be equally spread into all of the degrees of freedom, including translational, which increases the average kinetic energy of the gas molecules ‘heating’ them up.
Now, the opposite can also occur, translational energy (heat) can be converted into vibrational energy, and then that energy can be emitted as an IR photon.
reallyskeptical
November 19, 2017 7:30 am
” LWIR from CO2 is retained in the atmosphere longer, but it simply bounces around until it escapes into space without causing any warming.”
It’s not one way. Once LWIR is stopped, it (or it’s energy equivalent) has a 50% chance of escaping to space and 50% of escaping back to the surface.
CoRev
November 19, 2017 7:33 am
Joshv, this is the logical issue I am trying to resolve: “Think of a ** bunch of molecules bouncing around off of each** other, in a collision, one molecule could easily **lose much of it’s vibration or rotation** and cause the second molecule to bounce off faster in another direction. Over many collisions, the vibrational energy from IR absorbance will be equally spread into all of the degrees of freedom, including translational, which increases the average kinetic energy of the gas molecules ‘heating’ them up.”
To me that screams that CONDUCTION being the premier cause of atmospheric warming. That then leads to a whole larger series of questions related to radiational warming and COOLING.
Dr. Deanster
November 19, 2017 7:35 am
For the sake of discussion, the CO2 at 100 km in the atmosphere does not have to warm the liquid or solid surface below, it only need heat the gas directly below. Probably why these guys are always talking about a hot spot. …… but as we know, there is no hot spot.
My background is chemical movement in biological systems (pharmacokinetics) so you engineer guys feel free to correct me …. but the reason we don’t see a hot spot, IMO, is because radiation and energy move at the speed of light. From a biological perspective, this would equate to a 1/2 life in gases…. t-1/2, that for all practical purposes is near instantaneous. Thus, the only way for the atmosphere to stay warm is to have a continual supply of heat from solid and liquid surfaces, either directly or from flow (winds) from other places. That all goes back to heat capacity, where the oceans are king. We see this in observation, deserts cool very rapidly, and if not for an inflow of warmer air from surrounding areas, they would freeze every night. In contrast, oceans hold so much heat that they are capable of keeping the air above them warm within a very narrow max min range. …. for oceans it is an equation of energy input, which goes back to solar and clouds, and all that Jazz.
Thus, the atmospheric temp is 100% dependent on a constant inflow of heat. The GHG systems contribution is directly related to its heat capacity, and as you point out in your article, that would only be relevant at -80C, I’ll take your word for it regarding Wiens Law, but probabably also owing to the fact that relative to solids and liquid water, the GHG system has no heat capacity.
Oldie but goodie and a heck of a lot simpler and clearer.
References:
Trenberth et al 2011jcli24 Figure 10
This popular balance graphic and assorted variations are based on a power flux, W/m^2. A W is not energy, but energy over time, i.e. 3.4 Btu/eng h or 3.6 kJ/SI h. The 342 W/m^2 ISR is determined by spreading the average discular 1,368 W/m^2 solar irradiance/constant over the spherical ToA surface area. (1,368/4 =342) There is no consideration of the elliptical orbit (perihelion = 1,415 W/m^2 to aphelion = 1,323 W/m^2) or day or night or seasons or tropospheric thickness or energy diffusion due to oblique incidence, etc. This popular balance models the earth as a ball suspended in a hot fluid with heat/energy/power entering evenly over the entire ToA spherical surface. This is not even close to how the real earth energy balance works. Everybody uses it. Everybody should know better.
An example of a real heat balance based on Btu/h is as follows. Basically (Incoming Solar Radiation spread over the earth’s cross sectional area, Btu/h) = (U*A*dT et. al. leaving the lit side perpendicular to the spherical surface ToA, Btu/h) + (U*A*dT et. al. leaving the dark side perpendicular to spherical surface area ToA, Btu/h) The atmosphere is just a simple HVAC/heat flow/balance/insulation problem.
“Technically, there is no absolute dividing line between the Earth’s atmosphere and space, but for scientists studying the balance of incoming and outgoing energy on the Earth, it is conceptually useful to think of the altitude at about 100 kilometers above the Earth as the “top of the atmosphere.”
The top of the atmosphere is the bottom line of Earth’s energy budget, the Grand Central Station of radiation. It is the place where solar energy (mostly visible light) enters the Earth system and where both reflected light and invisible, thermal radiation from the Sun-warmed Earth exit. The balance between incoming and outgoing energy at the top of the atmosphere determines the Earth’s average temperature. The ability of greenhouses gases to change the balance by reducing how much thermal energy exits is what global warming is all about.”
ToA is 100 km or 62 miles. It is 68 miles between Denver and Colorado Springs. That’s not just thin, that’s ludicrous thin. 99% of the atmospheric mass is below 32 km. Above 32 km there are very few molecules. Without molecules, energy, heat, cold, hot concepts get a tad iffy.
The GHE/GHG loop as shown on Trenberth Figure 10 is made up of three main components: upwelling of 396 W/m^2 which has two sub parts: 63 W/m^2 LWIR and 333 W/m^2 and downwelling of 333 W/m^2.
The 396 W/m^2 is calculated by inserting 16 C or 279K in the S-B BB equation, a calculation that does not actually exist in the real world. The result is 55 W/m^2 of power flux more than ISR entering ToA, an obvious violation of conservation of energy, i.e. created out of nothing. That should have been a warning.
ISR of 341 W/m^2 enter ToA, 102 W/m^2 are reflected by the albedo, leaving a net 239 W/m^2 entering ToA. 78 W/m^2 are absorbed by the atmosphere leaving 161 W/m^2 for the surface. To maintain the overall energy balance and a steady temperature (not really a requirement) 160 W/m^2 rises from the surface (0.9 residual in ground) as 17 W/m^2 convection, 80 W/m^2 latent and 63 W/m^2 LWIR (S-B BB 183 K, -90 C or emissivity = .16) = 160 W/m^2. All of the graphic’s power fluxes are now present and accounted for. The remaining and perpetual looping 333 W/m^2 are the spontaneous creation of an inappropriate application of the S-B BB equation violating conservation of energy.
But let’s press on.
The 333 W/m^2 upwelling/downwelling constitutes a 100% efficient perpetual energy loop violating thermodynamics. There is no net energy left at the surface to warm the earth and there is no net energy left in the troposphere to impact radiative balance at ToA.
The 333 W/m^2, 97% of ISR, upwells into the troposphere where it is allegedly absorbed/trapped/blocked by a miniscule 0.04% of the atmosphere. That’s a significant heat load for such a tiny share of atmospheric molecules (aren’t any above 32 km) and they should all be hotter than two dollar pistols.
Except they aren’t.
The troposphere is cold, -40 C at 30,000 ft, 9 km, < -60 C at ToA. Depending on how one models the troposphere, an evenly distributed average or weighted by layers from surface to ToA, the S-B BB equation for the tropospheric temperatures ranges from 150 to 250 W/m^2, a considerable, 45% to 75% of, less than 333. Radiation is a surface phenomenon. There is no “surface.”
(99% of the atmosphere is below 32 km where molecular energy moves by convection/conduction/latent/radiation & where ideal S-B does not apply. Above 32 km the low molecular density does not allow for convection/conduction/latent and energy moves by S-B ideal radiation et. al.)
But wait!
The GHGs reradiate in all directions not just back to the surface. Say a statistical 33% makes it back to the surface that means 50 to 80 W/m^2. An even longer way away from the 333, 15% to 24% of.
But wait!
Because the troposphere is not ideal the S-B equation must consider emissivity. Nasif Nahle suggests CO2 emissivity could be around 0.1 or 5 to 8 W/m^2 re-radiated back to the surface. Light years from 333, 1.5% to 2.4% of.
But wait!
All of the above really doesn’t even matter since there is no net connection or influence between the 333 W/m^2 thermodynamically impossible loop and the radiative balance at 100 km ToA. Just erase this loop from the graphic and nothing else about the balance changes.
BTW 7 of the 8 reanalyzed (i.e. water board the data until it gives up the “right” answer) data sets/models show more power flux leaving OLR than entering ASR ToA or atmospheric cooling. Obviously those seven data sets/models have it completely wrong because there can’t possibly be any flaw in the GHE theory.
The GHE greenhouse analogy/theory not only does not apply to the atmosphere, it doesn’t even apply to warming a real greenhouse. (“The Discovery of Global Warming” Spencer Weart) In a real greenhouse the physical barrier of walls, glass, plastic trap the convective heat, not some kind of handwavium glassy, transparent, multi-layer, radiative thermal diode.
The surface of the earth is warm for the same reason a heated house is warm in the winter: Q = U * A * dT, the energy flow/heat resisting blanket of the insulated walls. Same for the atmospheric blanket. A blanket works by Q = U * A * dT, not S-B BB. The composite thermal conductivity of that paper-thin atmosphere, conduction, convection, latent, LWIR, resists the flow of energy, i.e. heat, from surface to ToA and to make that energy flow (heat) requires a temperature differential, 213 K ToA and 288 K surface = 75 C. The atmosphere is just a basic HVAC system boundary analysis.
Open for rebuttal. If you can explain how this upwelling/downwelling/”back” radiation actually really works be certain to copy Jennifer Marohasy as she has posted a challenge for such an explanation.
Nick Schroeder, BSME, PE
Latitude
November 19, 2017 7:43 am
If global warming theory went the other way……this would be just as feasible as what we are stuck with
The central error is here: “15um equates to 2898 ÷ 15 = 193K = -80C or -122F. In the atmosphere this temperature only occurs about 90-100Km high in the atmosphere.
Carbon Dioxide only emits and absorbs radiation at -80C from a narrow layer of atmosphere 90Km above the Earth’s surface.”
CO2 absorbs and reradiates 15μm band radiation at all altitudes and all temperatures, just the same as the antenna on your FM radio works in your living room by absorbing 3m band radiation at room temperature, not close to 0°K.
Anthony Mills
November 19, 2017 7:46 am
A good understanding of this issue can be obtained from Staley,D.O., and Jurica,G.M., “Effective atmospheric emissivity under clear skies” J.Applied Meteorology,v.11,349-356,March 1972. The physics of radiation transport in gas mixtures was well established many years ago.
jim
November 19, 2017 7:49 am
Don’t disagree with that. However the logical outturn is the same as Rod’s. The translational energy created in turn creates vibrational energy, ie it ‘bounces around’ until it dissipates into space. Unless CO2 truly is ‘magical’ or ‘evil’, its degrees of freedom alternate as you describe, but don’t affect anything else.
GHG’s are a red herring. Radiation doesn’t heat , convection heats. And the Earth doesn’t have a glass roof.
Martin Mason
November 19, 2017 7:49 am
Thanks for posting this Anthony, it is exactly how I as an engineer see it too. There is no other way that the first and second laws can be satisfied at real world and quantum level. It is the only interpretation of the theory that satisfies what we see happening and what has happened historically. Temperatures in the troposphere can be explained and calculated with no reference to back radiation so the conclusion surely has to be that back radiation doesn’t influence temperature.
Bill Illis
November 19, 2017 7:49 am
“For example Oxygen and Nitrogen do not absorb or emit Long Wave Infrared Radiation (LWIR) at all, so are not considered to be “Greenhouse” gases.”
– They do NOT absorb photons in Long Wave but they absorb energy at the same “levels” through collisional energy exchange and pass on energy to other molecules at the same “levels” through the same collisions.
The most misunderstood aspect of this whole debate. Nitrogen and Oxygen just sit there all inert-like and are not part of the process is simply not correct. 98% of the atmosphere has the temperature/energy level of the “atmosphere”.
The author is wrong on many points.The first is the point that CO2 only radiates to space from a very high altitude. In fact it radiates to space from a range of altitudes almost all the way through the atmosphere, although the peak amount of atmospheric radiation to space occurs relative high from about 5 to 15 km. Also radiation directly from the ground is a big factor, especially over deserts and very high latitudes. In addition, the radiation from water vapor and especially clouds is a major source of radiation to space. However with all of that said, increasing CO2 does increase the atmospheric trapping of radiation, which in effect acts like a radiation insulation, and by itself would increase the surface temperature. However, changes in clouds, transport of surface heating by ocean currents, and wind and storage and release by oceans may reduce the effect of the CO2, or may amplify it with the increased water vapor due to increased temperature. So far the data is inconclusive, but seems to indicate small to negligible net CO2 effect, but not due to the authors arguments. In the end, the lapse rate and effective average altitude of radiation to space determine the atmospheric greenhouse effect.
I am not disagreeing with anything (yet). But I would like to make a few comments before all and sundry jump in:
Photon s are NOT real massless particles. The concept of a photon is a human construct from our mind in an attempt to observe the apparent “lumpiness” of certain phenomena with electro-magnetic radiation.
E-M Radiation CANNOT be directly observed, you can only observe the effect on real matter, and we know real matter is “lumpy” (particles). It MAY be the case that e-m radiation is not in any way “quantised” but is purely analogue and only the effects seem to suggest quantisation hence the concept of the photon.
Try, if possible, making your arguments work BOTH for photons (quantised e-m lumps) and also for e-m which is not quantised. You may need 2 completely different arguments. I suggest the results of doing this will (or may be) illuminating (pun intended).
My final comment is that the understanding of this, i.e. RADIATION, as it applies in the real world is THE most important thing we need to grasp in considering CAGW. and if we cannot grasp it correctly and securely by logical argument then let’s have some suggestions from you for REAL WORLD EXPERIMENTS to settle the issue(s).
‘Their orbital height is not variable, But fixed. The electrons only orbit at set altitudes, the closer to the molecule the lower the kinetic energy of the molecule and so the lower the molecule’s temperature.’
The closer to the nucleus?
Ah, the upside down greenhouse effect. Things haven’t panned out quite the way it was explained ~30 years ago using basic high school physics as we’re constantly reminded.
http://1clickurl.com/XYwCjxT
A “good-faith effort” indeed, but, IMHO, Rod Gill misapplies the equations he uses and misinterprets the results. Satellite views of long wave radiation from Earth to Space, looking down, and views of long radiation from Space to Earth, looking up from the surface, show the actual warming effects of water vapor, CO2, and other “greenhouse” gases.
I’ve never heard a weather forecast yet that said, it’s going to be a high CO2 night, which is expected to keep temperatures warmer. They always say, lots of cloud cover tonight will help keep temperatures warmer, or the lack of cloud cover tonight will see temperatures plunge. If CO2 makes temperatures warmer, then we here in middle Alberta have been shortchanged for the last three weeks. So I don’t disagree with anything you say.
Carbon Dioxide only emits and absorbs radiation at -80C from a narrow layer of atmosphere 90Km above the Earth’s surface.
Why do you say that? Things do not emit radiation ONLY at their peak wavelength. They emit at that wavelength and also at others.
Does beg the question how much energy in the wavelength that CO2 absorbs is reflected back towards space. This will tell us the maximum possible amount of heat that CO2 can trap.
It will not stop warmists as CO2 will cause a positive feedback loop that increases H20 in the atmosphere.
But as H2O increases so the energy available to warm CO2 will therefore decrease.
How do I feel that this green house theory is not fully explained.
The very first key point is dead wrong. Electron ‘orbit height’ (energy level) does NOT change with temperature. ‘Temperature’ is the molecular level vibration/velocity/Kinetic energy, not subatomic (within the atoms). That’s what I was taught. Google can get this right, https://www.quora.com/By-lowering-temperature-the-atoms-slow-down-So-do-the-electrons-in-the-atom-also-slow-down
Here’s a references to an n layer atmosphere:
http://en.wikipedia.org/wiki/Idealized_greenhouse_model
GREENHOUSE WARMING Part I
There IS a greenhouse gas effect. Here’s an example.
Let the flux from the sun to the ground be 4 joules/unit time*unit
area,
and stay constant.
–> SUN
–>
–>
–>
–>
With no greenhouse gases, the earth will either heat up or cool down
until
the outgoing flux from the earth is equal to the incoming flux from
the sun.
Sun –> O O O O <– <– <–O O–> <–
You've now got an unbalanced situation where 5 joules/unit time*unit
area
are hitting the earth, 4 from the sun and half of the 2 from the
atmosphere,
and only 3 joules per second are leaving the earth, the 2 not
absorbed by
the gas, and half of the 2 from the atmosphere. The atmosphere will
gradually
warm up until outgoing flux from the atmosphere, plus the fraction of
the flux from the
earth not intercepted by the atmosphere, equals the incoming amount
from the sun.
Since in my example, half of the outgong flux is intercepted by the
atmosphere,
the watts hitting the earth's surface will increase to
1/(1-1/4) = 4/3 of 4 joules/(unit time*unit area) = 5 1/3 joules/(unit
time*unit area).
Remember the atmosphere is intercepting half of this, so 16/6 joules
(unit time*unit area)
is intercepted by the greenhouse gas atmosphere, and another half,
16/6 joules, escapes
directly to space.
The final equilibrium balance is
16/12 Earth
O–>16/12 16/12(from atmosphere)–>Earth
Sun –>4
16/6 to atmosphere <–
Earth
16/6 to space <–
Earth
So yes, a greenhouse gas will warm the earth, the amount of warming
depends on the fraction
of the outgoing (and incoming for that matter) radiation absorbed by
the atmosphere.
………………………………………………..
If the atmosphere was absorbing ALL radiation from the sun , you'd get a final balance of
4 watts/unit area from sun to atmosphere and 4 watts from atmosphere to space- in balance
4 watts from sun to atmosphere, 4 watts from earth's surface to atmosphere
4 watts from atmosphere to space, 4 watts from atmosphere to earth surface- in balance
4 watts from atmosphere to earth surface, 4 watts from earth surface to atmosphere – in balance.
So an atmosphere that absorbed ALL solar radiation would have a net zero greenhouse effect.
……………………………………………………….
When you look at the blackbody radiation curve, you'll notice that the shortwave frequencies, not affected by CO2, increase at a much greater rate with increasing temperature than longer wave radiation, which IS affected by the amount of CO2 in the air. The net result is that increasing absorption of long wave radiation by CO2 is MUCH smaller than increases in surface temperature. In addition, as the atmosphere warms up, a larger fraction of the sun's incoming radiation is absorbed directly by the atmosphere, reducing the overall greenhouse effect.
I agree with your findings, but not for the same reasons. Retired now, I used to be a laser engineer, and instrument design engineer, including weather stations, and all manner of energy measuring devices. I created infrared measurement systems and laser energy measurement systems. Thus, I know a little about gas behavior and thermal characteristics.
So, my argument against CO2 ‘warming’ anything goes like this? If it DID increase the surface temperature, the surface would radiate to space at the 4th power of the increase, instantly cooling itself back down. We know that everything radiates and we have laws for quantifying it.
Experiment: Try to heat a stove with a flashlight. There are lots of photons, you can see them. Yet the stove does not warm. Why? Because for each photon that strikes the stove, the stove emits millions, maybe billions of photons itself. Those few photons from the flashlight are simply overwhelmed, and the result is immeasurable. Applying that to CO2, how many surface molecules radiate for every CO2 molecule? There is NO WAY there is sufficient energy in CO2 radiation from the atmosphere to increase surface temperature, because the surface radiates FAR more than the CO2 does. And, again, if the CO2 DID somehow manage to ‘warm’ the surface, it’s millions of molecules per CO2 molecule would simply radiate at a higher rate instantaneously, and ‘cool’ back to equilibrium.
Lastly, consider that if there were CO2 ‘radiation’, it would cast a shadow when blocked – an invisible one, but still a shadow. If you create a filter that can filter out the CO2 spectrum, and place it on the window of an infrared thermometer, with another identical thermometer without the filter, you will find that they both measure the same temperature. That would not be possible, if CO2 was indeed ‘heating’ anything, those two thermometers would have to read differently.
I will not start arguiing about the physical phenomenon in a GH molecule, when a photon with the right wavelenght / frequency hits this molecule. This is a very basic stuff of molecular physics and there is enough evidence in which way it happnes. But I do not agree with the description of Rod Gill.
The GH effect in the atmosphere is a fact and it is caused by GH gases: H2O 81 %, CO2 13 %, O3 4 % CH4 & N2O 1 %, clouds 1 %. Link: http://www.sciencedomain.org/abstract/17484
Here is a figure from my web site, which shows the absorption wavelenghts of GH gases. A very bsic thing is that the absorption wavelenghts of other GH gases overlaps with water making them rather weak:
One thing more. The Earth’s surface emits about 395 W/m2 in 15 degrees and the LW radition emitted by the atmosphere to space is about 239 W/m2. The radiation loss is 396 – 239 = 157 W/2. Energy does not disappear but it can change its form. The radiation flux of 157 W/m2 maintains the temperature profile of the atmosphere together with the SW radiation absorpbed by the atmosphere, which is about 71 W/2.
A nice essay, I don’t fully understand quantum physics, you have a much greater knowledge of this than me. Could I ask though there is a theory, I am not sure it is conclusive, that as CO2 concentration rises in the atmosphere, the increase in temperature is not linear, but logarithmic. If it is true how would this tie in with your theory? I have pasted my source below which is over 8 years old.
https://wattsupwiththat.com/2010/03/08/the-logarithmic-effect-of-carbon-dioxide/
Whatever the theory, CO2 obviously does not cause actual warming by experiment in the real atmosphere. The increase in CO2 in the ca. one hundred years from near 300PPM to near 400PPM does not correlate with global warming, or some would say, lack thereof.
You’ve got the physics wrong. Absorption spectra have little to do with electrons, and a lot to do with vibration modes of the CO2 molecule. CO2 is a complex molecule. It can move (translation), rotate, and vibrate. A molecule’s energy is equally partitioned between all of these degrees of freedom. The rotational and translational degrees of freedom cannot absorb IR, but the vibration degree of freedom can. The energy from IR, once absorbed by resonance with a vibrational mode, can then be distributed to the other modes. It does not stay ‘locked up’ in vibration, it can cause the molecule to rotate, and to move faster (heat up).
Think of a bunch of molecules bouncing around off of each other, in a collision, one molecule could easily lose much of it’s vibration or rotation and cause the second molecule to bounce off faster in another direction. Over many collisions, the vibrational energy from IR absorbance will be equally spread into all of the degrees of freedom, including translational, which increases the average kinetic energy of the gas molecules ‘heating’ them up.
Now, the opposite can also occur, translational energy (heat) can be converted into vibrational energy, and then that energy can be emitted as an IR photon.
” LWIR from CO2 is retained in the atmosphere longer, but it simply bounces around until it escapes into space without causing any warming.”
It’s not one way. Once LWIR is stopped, it (or it’s energy equivalent) has a 50% chance of escaping to space and 50% of escaping back to the surface.
Joshv, this is the logical issue I am trying to resolve: “Think of a ** bunch of molecules bouncing around off of each** other, in a collision, one molecule could easily **lose much of it’s vibration or rotation** and cause the second molecule to bounce off faster in another direction. Over many collisions, the vibrational energy from IR absorbance will be equally spread into all of the degrees of freedom, including translational, which increases the average kinetic energy of the gas molecules ‘heating’ them up.”
To me that screams that CONDUCTION being the premier cause of atmospheric warming. That then leads to a whole larger series of questions related to radiational warming and COOLING.
For the sake of discussion, the CO2 at 100 km in the atmosphere does not have to warm the liquid or solid surface below, it only need heat the gas directly below. Probably why these guys are always talking about a hot spot. …… but as we know, there is no hot spot.
My background is chemical movement in biological systems (pharmacokinetics) so you engineer guys feel free to correct me …. but the reason we don’t see a hot spot, IMO, is because radiation and energy move at the speed of light. From a biological perspective, this would equate to a 1/2 life in gases…. t-1/2, that for all practical purposes is near instantaneous. Thus, the only way for the atmosphere to stay warm is to have a continual supply of heat from solid and liquid surfaces, either directly or from flow (winds) from other places. That all goes back to heat capacity, where the oceans are king. We see this in observation, deserts cool very rapidly, and if not for an inflow of warmer air from surrounding areas, they would freeze every night. In contrast, oceans hold so much heat that they are capable of keeping the air above them warm within a very narrow max min range. …. for oceans it is an equation of energy input, which goes back to solar and clouds, and all that Jazz.
Thus, the atmospheric temp is 100% dependent on a constant inflow of heat. The GHG systems contribution is directly related to its heat capacity, and as you point out in your article, that would only be relevant at -80C, I’ll take your word for it regarding Wiens Law, but probabably also owing to the fact that relative to solids and liquid water, the GHG system has no heat capacity.
Oldie but goodie and a heck of a lot simpler and clearer.
References:
Trenberth et al 2011jcli24 Figure 10
This popular balance graphic and assorted variations are based on a power flux, W/m^2. A W is not energy, but energy over time, i.e. 3.4 Btu/eng h or 3.6 kJ/SI h. The 342 W/m^2 ISR is determined by spreading the average discular 1,368 W/m^2 solar irradiance/constant over the spherical ToA surface area. (1,368/4 =342) There is no consideration of the elliptical orbit (perihelion = 1,415 W/m^2 to aphelion = 1,323 W/m^2) or day or night or seasons or tropospheric thickness or energy diffusion due to oblique incidence, etc. This popular balance models the earth as a ball suspended in a hot fluid with heat/energy/power entering evenly over the entire ToA spherical surface. This is not even close to how the real earth energy balance works. Everybody uses it. Everybody should know better.
An example of a real heat balance based on Btu/h is as follows. Basically (Incoming Solar Radiation spread over the earth’s cross sectional area, Btu/h) = (U*A*dT et. al. leaving the lit side perpendicular to the spherical surface ToA, Btu/h) + (U*A*dT et. al. leaving the dark side perpendicular to spherical surface area ToA, Btu/h) The atmosphere is just a simple HVAC/heat flow/balance/insulation problem.
http://earthobservatory.nasa.gov/IOTD/view.php?id=7373
“Technically, there is no absolute dividing line between the Earth’s atmosphere and space, but for scientists studying the balance of incoming and outgoing energy on the Earth, it is conceptually useful to think of the altitude at about 100 kilometers above the Earth as the “top of the atmosphere.”
The top of the atmosphere is the bottom line of Earth’s energy budget, the Grand Central Station of radiation. It is the place where solar energy (mostly visible light) enters the Earth system and where both reflected light and invisible, thermal radiation from the Sun-warmed Earth exit. The balance between incoming and outgoing energy at the top of the atmosphere determines the Earth’s average temperature. The ability of greenhouses gases to change the balance by reducing how much thermal energy exits is what global warming is all about.”
ToA is 100 km or 62 miles. It is 68 miles between Denver and Colorado Springs. That’s not just thin, that’s ludicrous thin. 99% of the atmospheric mass is below 32 km. Above 32 km there are very few molecules. Without molecules, energy, heat, cold, hot concepts get a tad iffy.
The GHE/GHG loop as shown on Trenberth Figure 10 is made up of three main components: upwelling of 396 W/m^2 which has two sub parts: 63 W/m^2 LWIR and 333 W/m^2 and downwelling of 333 W/m^2.
The 396 W/m^2 is calculated by inserting 16 C or 279K in the S-B BB equation, a calculation that does not actually exist in the real world. The result is 55 W/m^2 of power flux more than ISR entering ToA, an obvious violation of conservation of energy, i.e. created out of nothing. That should have been a warning.
ISR of 341 W/m^2 enter ToA, 102 W/m^2 are reflected by the albedo, leaving a net 239 W/m^2 entering ToA. 78 W/m^2 are absorbed by the atmosphere leaving 161 W/m^2 for the surface. To maintain the overall energy balance and a steady temperature (not really a requirement) 160 W/m^2 rises from the surface (0.9 residual in ground) as 17 W/m^2 convection, 80 W/m^2 latent and 63 W/m^2 LWIR (S-B BB 183 K, -90 C or emissivity = .16) = 160 W/m^2. All of the graphic’s power fluxes are now present and accounted for. The remaining and perpetual looping 333 W/m^2 are the spontaneous creation of an inappropriate application of the S-B BB equation violating conservation of energy.
But let’s press on.
The 333 W/m^2 upwelling/downwelling constitutes a 100% efficient perpetual energy loop violating thermodynamics. There is no net energy left at the surface to warm the earth and there is no net energy left in the troposphere to impact radiative balance at ToA.
The 333 W/m^2, 97% of ISR, upwells into the troposphere where it is allegedly absorbed/trapped/blocked by a miniscule 0.04% of the atmosphere. That’s a significant heat load for such a tiny share of atmospheric molecules (aren’t any above 32 km) and they should all be hotter than two dollar pistols.
Except they aren’t.
The troposphere is cold, -40 C at 30,000 ft, 9 km, < -60 C at ToA. Depending on how one models the troposphere, an evenly distributed average or weighted by layers from surface to ToA, the S-B BB equation for the tropospheric temperatures ranges from 150 to 250 W/m^2, a considerable, 45% to 75% of, less than 333. Radiation is a surface phenomenon. There is no “surface.”
(99% of the atmosphere is below 32 km where molecular energy moves by convection/conduction/latent/radiation & where ideal S-B does not apply. Above 32 km the low molecular density does not allow for convection/conduction/latent and energy moves by S-B ideal radiation et. al.)
But wait!
The GHGs reradiate in all directions not just back to the surface. Say a statistical 33% makes it back to the surface that means 50 to 80 W/m^2. An even longer way away from the 333, 15% to 24% of.
But wait!
Because the troposphere is not ideal the S-B equation must consider emissivity. Nasif Nahle suggests CO2 emissivity could be around 0.1 or 5 to 8 W/m^2 re-radiated back to the surface. Light years from 333, 1.5% to 2.4% of.
But wait!
All of the above really doesn’t even matter since there is no net connection or influence between the 333 W/m^2 thermodynamically impossible loop and the radiative balance at 100 km ToA. Just erase this loop from the graphic and nothing else about the balance changes.
BTW 7 of the 8 reanalyzed (i.e. water board the data until it gives up the “right” answer) data sets/models show more power flux leaving OLR than entering ASR ToA or atmospheric cooling. Obviously those seven data sets/models have it completely wrong because there can’t possibly be any flaw in the GHE theory.
The GHE greenhouse analogy/theory not only does not apply to the atmosphere, it doesn’t even apply to warming a real greenhouse. (“The Discovery of Global Warming” Spencer Weart) In a real greenhouse the physical barrier of walls, glass, plastic trap the convective heat, not some kind of handwavium glassy, transparent, multi-layer, radiative thermal diode.
The surface of the earth is warm for the same reason a heated house is warm in the winter: Q = U * A * dT, the energy flow/heat resisting blanket of the insulated walls. Same for the atmospheric blanket. A blanket works by Q = U * A * dT, not S-B BB. The composite thermal conductivity of that paper-thin atmosphere, conduction, convection, latent, LWIR, resists the flow of energy, i.e. heat, from surface to ToA and to make that energy flow (heat) requires a temperature differential, 213 K ToA and 288 K surface = 75 C. The atmosphere is just a basic HVAC system boundary analysis.
Open for rebuttal. If you can explain how this upwelling/downwelling/”back” radiation actually really works be certain to copy Jennifer Marohasy as she has posted a challenge for such an explanation.
Nick Schroeder, BSME, PE
If global warming theory went the other way……this would be just as feasible as what we are stuck with
The central error is here: “15um equates to 2898 ÷ 15 = 193K = -80C or -122F. In the atmosphere this temperature only occurs about 90-100Km high in the atmosphere.
Carbon Dioxide only emits and absorbs radiation at -80C from a narrow layer of atmosphere 90Km above the Earth’s surface.”
CO2 absorbs and reradiates 15μm band radiation at all altitudes and all temperatures, just the same as the antenna on your FM radio works in your living room by absorbing 3m band radiation at room temperature, not close to 0°K.
A good understanding of this issue can be obtained from Staley,D.O., and Jurica,G.M., “Effective atmospheric emissivity under clear skies” J.Applied Meteorology,v.11,349-356,March 1972. The physics of radiation transport in gas mixtures was well established many years ago.
Don’t disagree with that. However the logical outturn is the same as Rod’s. The translational energy created in turn creates vibrational energy, ie it ‘bounces around’ until it dissipates into space. Unless CO2 truly is ‘magical’ or ‘evil’, its degrees of freedom alternate as you describe, but don’t affect anything else.
GHG’s are a red herring. Radiation doesn’t heat , convection heats. And the Earth doesn’t have a glass roof.
Thanks for posting this Anthony, it is exactly how I as an engineer see it too. There is no other way that the first and second laws can be satisfied at real world and quantum level. It is the only interpretation of the theory that satisfies what we see happening and what has happened historically. Temperatures in the troposphere can be explained and calculated with no reference to back radiation so the conclusion surely has to be that back radiation doesn’t influence temperature.
“For example Oxygen and Nitrogen do not absorb or emit Long Wave Infrared Radiation (LWIR) at all, so are not considered to be “Greenhouse” gases.”
– They do NOT absorb photons in Long Wave but they absorb energy at the same “levels” through collisional energy exchange and pass on energy to other molecules at the same “levels” through the same collisions.
The most misunderstood aspect of this whole debate. Nitrogen and Oxygen just sit there all inert-like and are not part of the process is simply not correct. 98% of the atmosphere has the temperature/energy level of the “atmosphere”.
(Edited) MOD
The author is wrong on many points.The first is the point that CO2 only radiates to space from a very high altitude. In fact it radiates to space from a range of altitudes almost all the way through the atmosphere, although the peak amount of atmospheric radiation to space occurs relative high from about 5 to 15 km. Also radiation directly from the ground is a big factor, especially over deserts and very high latitudes. In addition, the radiation from water vapor and especially clouds is a major source of radiation to space. However with all of that said, increasing CO2 does increase the atmospheric trapping of radiation, which in effect acts like a radiation insulation, and by itself would increase the surface temperature. However, changes in clouds, transport of surface heating by ocean currents, and wind and storage and release by oceans may reduce the effect of the CO2, or may amplify it with the increased water vapor due to increased temperature. So far the data is inconclusive, but seems to indicate small to negligible net CO2 effect, but not due to the authors arguments. In the end, the lapse rate and effective average altitude of radiation to space determine the atmospheric greenhouse effect.