Guest Post by Ira Glickstein
The Unified Theory of Climate post is exciting and could shake the world of Climate Science to its roots. I would love it if the conventional understanding of the Atmospheric “Greenhouse” Effect (GHE) presented by the Official Climate Team could be overturned, and that would be the case if the theory of Ned Nikolov and Karl Zeller, both PhDs, turns out to be scientifically correct.
Sadly, it seems to me they have made some basic mistakes that, among other faults, confuse cause and effect. I appreciate that WUWT is open to new ideas, and I support the decision to publish this theory, along with both positive and negative comments by readers.
Correlation does not prove causation. For example, the more policemen directing traffic, the worse the jam is. Yes, when the police and tow trucks first respond to an accident they may slow the traffic down a bit until the disabled automobiles are removed. However, there is no doubt the original cause of the jam was the accident, and the reason police presence is generally proportional to the severity of the jam level is that more or fewer are ordered to respond. Thus, Accident >>CAUSES>> Traffic Jam >>CAUSES>> Police is the correct interpretation.
Al Gore made a similar error when, in his infamous movie An Inconvenient Truth, he made a big deal about the undoubted corrrelation in the Ice Core record between CO2 levels and Temperature without mentioning the equally apparent fact that Temperatures increase and decrease hundreds of years before CO2 levels follow suit.
While it is true that rising CO2 levels do have a positive feedback that contributes to slightly increased Temperatures, the primary direction of causation is Temperature >>CAUSES>> CO2. The proof is in the fact that, in each Glacial cycle, Temperatures begin their rapid decline precisely when CO2 levels are at their highest, and rapid Temperature increase is initiated exactly when CO2 levels are their lowest. Thus, Something Else >>CAUSES>> Temperature>>CAUSES>> CO2. Further proof may be had by placing an open can of carbonated beverage in the refigerator and another on the table, and noting that the “fizz” (CO2) outgasses more rapidly from the can at room temperature.
Moving on to Nikolov, the claim appears to be that the pressure of the Atmosphere is the main cause of temperature changes on Earth. The basic claim is PRESSURE >>CAUSES>>TEMPERATURE.
PV = nRT
Given a gas in a container, the above formula allows us to calculate the effect of changes to the following variables: Pressure (P), Volume (V), Temperature (T, in Kelvins), and Number of molecules (n). (R is a constant.)
The figure shows two cases involving a sealed, non-insulated container, with a Volume, V, of air:
(A) Store that container of air in the ambient cool Temperature Tr of a refrigerator. Then, increase the Number n of molecules in the container by pumping in more air. the Pressure (P) within the container will increase. Due to the work done to compress the air in the fixed volume container, the Temperature within the container will also increase from (Tr) to some higher value. But, please note, when we stop increasing n, both P and T in the container will stabilize. Then, as the container, warmed by the work we did compressing the air, radiates, conducts, and convects that heat to the cool interior of the refrigerator, the Temperature slowly decreases back to the original Tr.
(B) We take a similar container from the cool refrigerator at Temperature Tr and place it on a kitchen chair, where the ambient Temperature Tk is higher. The container is warmed by radiation, conduction and convection and the Temperature rises asymptotically towards Tk. The Pressure P rises slowly and stabilizes at some higher level. Please note the pressure remains high forever so long as the temperature remains elevated.
In case (A) Pressure >>CAUSES A TEMPORARY>> increase in Temperature.
In case (B) Temperature >>CAUSES A PERMANENT>> increase in Pressure.
I do not believe any reader will disagree with this highly simplified thought experiment. Of course, the Nikolov theory is far more complex, but, I believe it amounts to confusing the cause, namely radiation from the Sun and Downwelling Long-Wave Infrared (LW DWIR) from the so-called “Greenhouse” gases (GHG) in the Atmosphere with the effect, Atmospheric pressure.
Some Red Flags in the Unified Theory
1) According to Nikolov, our Atmosphere
“… boosts Earth’s surface temperature not by 18K—33K as currently assumed, but by 133K!”
If, as Nikolov claims, the Atmosphere boosts the surface temperature by 133K, then, absent the Atmosphere the Earth would be 288K – 133K = 155K. This is contradicted by the fact that the Moon, which has no Atmosphere and is at the same distance from the Sun as our Earth, has an average temperature of about 250K. Yes, the albedo of the Moon is 0.12 and that of the Earth is 0.3, but that difference would make the Moon only about 8K cooler than an Atmosphere-free Earth, not 95K cooler! Impossible!
2) In the following quote from Nikolov, NTE is “Atmospheric Near-Surface Thermal Enhancement” and SPGB is a “Standard Planetary Gray Body”
NTE should not be confused with an actual energy, however, since it only defines the relative (fractional) increase of a planet’s surface temperature above that of a SPGB. Pressure by itself is not a source of energy! Instead, it enhances (amplifies) the energy supplied by an external source such as the Sun through density-dependent rates of molecular collision. This relative enhancement only manifests as an actual energy in the presence of external heating. [Emphasis added]
This, it seems to me, is an admission that the source of energy for their “Atmospheric Near-Surface Thermal Enhancement” process comes from the Sun, and, therefore, their “Enhancement” is as they admit, not “actual energy”. I would add the energy that would otherwise be lost to space (DW LWIR) to the energy from the Sun, eliminating any need for the “Thermal Enhancement” provided by Atmospheric pressure.
3) As we know when investigating financial misconduct, follow the money. Well, in Climate Science we follow the Energy. We know from actual measurements (see my Visualizing the “Greenhouse” Effect – Emission-Spectra) the radiative energy and spectra of Upwelling Long-Wave Infrared (UW LWIR), from the Surface to the so-called “greenhouse” gases (GHG) in the Atmosphere, and the Downwelling (DW LWIR) from those gases back to the Surface.
The only heed Nikolov seems to give to GHG and those measured radiative energies is that they are insufficient to raise the temperature of the Surface by 133K.
… our atmosphere boosts Earth’s surface temperature not by 18K—33K as currently assumed, but by 133K! This raises the question: Can a handful of trace gases which amount to less than 0.5% of atmospheric mass trap enough radiant heat to cause such a huge thermal enhancement at the surface? Thermodynamics tells us that this not possible.
Of course not! Which is why the conventional explanation of the GHE is that the GHE raises the temperature by only about 33K (or perhaps a bit less -or more- but only a bit and definitely not 100K!).
4) Nikolov notes that, based on “interplanetary data in Table 1” (Mercury, Venus, Earth, Moon, Mars, Europe, Titan, Triton):
… we discovered that NTE was strongly related to total surface pressure through a nearly perfect regression fit…
Of course, one would expect planets and moons in our Solar system to have some similarities.
“… the atmosphere does not act as a ‘blanket’ reducing the surface infrared cooling to space as maintained by the current GH theory, but is in and of itself a source of extra energy through pressure. This makes the GH effect a thermodynamic phenomenon, not a radiative one as presently assumed!
I just cannot square this assertion with the clear measurements of UW and DW LWIR, and the fact that the wavelengths involved are exactly those of water vapor, carbon dioxide, and other GHGs.
Equation (7) allows us to derive a simple yet robust formula for predicting a planet’s mean surface temperature as a function of only two variables – TOA solar irradiance and mean atmospheric surface pressure,…”
Yes, TOA solar irradiance would be expected to be important in predicting mean surface temperature, but mean atmospheric surface pressure, it seems to me, would more likely be a result than a cause of temperature. But, I could be wrong.
Conclusion
I, as much as anyone else here at WUWT, would love to see the Official Climate Team put in its proper place. I think climate (CO2) sensitivity is less than the IPCC 2ºC to 4.5ºC, and most likely below 1ºC. The Nikolov Unified Climate Theory goes in the direction of reducing climate sensitivity, apparently even making it negative, but, much as I would like to accept it, I remain unconvinced. Nevertheless, I congratulate Nikolov and Zeller for having the courage and tenacity to put this theory forward. Perhaps it will trigger some other alternative theory that will be more successful.
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UPDATE: This thread is closed – see the newest one “A matter of some Gravity” where the discussion continues.
Willis Eschenbach says:
January 4, 2012 at 10:16 am
I’ve been waiting a couple of days for someone to answer Willises question to no avail.
Seen that the question is from one of my Climate Blogosphere Heroes, I’ll try to answer to the best of my ability.
Take a hypothetical planet called Esch. When it had no atmosphere, Esch received enough energy from its sun to cause its equator to be 30DegC and its poles to be 0DegC. (an average of 15DegC and lets say that that equates to the 235Wm2 number).
Now we add non-ghg gasses as an atmosphere.
At the equator, conduction warms the air immediately above the ground. This air rises and is replaced by cooler air which in turn also warms and rises. This goes on all day.
At night (Esch is a rotating planet just like Earth), the ground cools which in turn cools the air just above it. However, cool air does not rise nor does warm air fall, so we end up with a temperature inversion. The air at altitude, which was warmed during the day whilst at ground level, stays warm because it can’t radiate.
We now reach the 2nd day BUT we have a portion of the atmosphere that was warmer than the day before.
As the above process continues day after day, year after year, the air that is warmed by the ground is distributed around the planet via temperature differential.
How warm will this planet get? The whole planet, including the poles, will attain a temperature of 30DegC (the same as the equator).
Esch WITH a non-ghg atmosphere would still emit directly from the ground that incoming 235Wm2, (since non-ghgs are transparent to ULWR) however it now has an atmospheric temperature of 30DegC.
No thermodynamic laws broken.
p.s.
I had posed a question at 8:43pm Jan 2nd, http://wattsupwiththat.com/2011/12/29/unified-climate-theory-may-confuse-cause-and-effect/#comment-851272 which no one has answered yet. I really would appreciate an answer from someone who knows these things.
The more I watch this debate the more blindingly obvious it becomes that N&Z are right.
Willis et al, you’ve asked for a physical mechanism and Richard S Courtney gave it to you. If I may, here is his explanation in slightly different terms.
Assumptions
Rocky planet.
atmosphere that neither absorbs nor emitts
average insolation of 240 w/m2
Goal
Mechanism by which the presence of the atmopshere raises average T without raising average P.
Explanation
By SB Law, we expect an average T of -17.9 C
However, we CANNOT calculate average of T for a given average P since P doesn’t vary with T but with T^4!
FURTHER, the atmosphere, while it cannot absorb or emitt, must still participate in energy transfer via conductance and convection. This has no possible result but to remove energy from the “tropics” (which receive higher than average insolation and are at a higher than average T) to the “arctic zones” (which receive lower than average insolation and so are at a lower than average T)
Example calculation
Assumptions
Without presence of atmosphere:
Tropics are subject to an average P of 2 x 240 = 480.
Vis SB Law, T = 30 C
Arctic Zones are subject to an average P of 0
Via SB Law, T = -273 C
Assumptions
WITH presence of atmosphere
Some portion of P at the tropics is transferred to the atmosphere via conduction. This in turn causes convection. The convection in turn moves warm air from the tropics to the arctic zones, and cool air the other way. This cools the tropics and warms the arctic. For the purposes of simplicity, let us assume equal areas between the tropics and the arctics. Let us further assume that the net effect is to cool the tropics by 50 w/m2 and warm an equal area of the arctics by 50 w/m2. Let us apply SB LAw to see affect on temperatures.
Tropics = 480 – 50 = 430
Via SB Law, T = 22 C
Change = -8 degrees.
Arctics = 0 + 50 = 50
Via SB Law, T = -100 C
Change = + 173 degrees
And there you have your mechanism. By removing 50 w/m2 from the tropics, that area sees a reduction in temperature of 8 degrees. The 50 w/m2 added to an equal area in the artic sees an increase in temperature of 173 degrees. Since the areas are equal in size, and one decreased in P by the same amount as the other increased in P, the laws of thermodynamics are intact.
Average T however is higher. MUCH higher.
Average T^4 HAS NOT CHANGED!
Average P HAS NOT CHANGED!
Of course you’d never actually get 0 degrees K at the poles even in a planet with no atmosphere because the planet ITSELF will conduct heat from the tropics to the poles to some extent. There are other minutia I can think of that would throw the numbers off, but this should serve to illustrate a mechanism by which the presence of an atmosphere increases average T simply by redistributing energy from the “hot” zones to the “cold” zones via conduction and convection.
And that is why relying on the average of T instead of the average of T^4 has bolloxed up this entire conversation for the last several decades. average of T means diddly squat. average of T^4 is the ONLY way to determine if the planet is in an energy imbalance and by how much.
Paul Bahlin says:
January 4, 2012 at 5:35 am
I thought EVERYTHING above absolute zero radiates energy. Just because nitrogen doesn’t capture and subsequently radiate radiant energy doesn’t mean it can’t capture energy through conduction and collisions and radiate that as infrared.
Help!!!!
A common misconception on this site, gas molecules (or atoms) are only going to emit at atmospheric temperatures as a result of vibrational/rotational transitions, Argon atoms don’t have vibrational/rotational energy levels so they can’t absorb/emit via this mechanism. Similarly homonuclear diatomics like N2 and O2 don’t have a dipole so they can’t absorb/emit via this mechanism even though they vibrate and rotate. (There are some incredibly weak bands for both O2 and N2 in the vicinity of 5μm but they are ~10 orders of magnitude weaker than CO2/H2O)
HTH
Willis Eschenbach @ur momisugly January 4, 1:33 am
Ah good Willis, I think we are making progress in that you admit that a planet with an atmosphere of nitrogen will be warmer than one without an atmosphere. Well that’s what you appear to be saying, I think. An outstanding issue is that with a nitrogen atmosphere, you say that all of the insolation is radiated directly to space from the surface, but meanwhile there are a bunch of other energy related things going on, such as those mentioned by Richard Courtney @ur momisugly January 4, 2:20 am. Is this perhaps behind your question, where does the extra energy come from? Of course it’s all a tad difficult, but perhaps you can make a few assertions on that too.
mkelly says:
January 4, 2012 at 6:26 am
The iceman cometh says:
January 3, 2012 at 9:46 pm
“Iceman, the N2 or O2 molecules can heat up via conduction with the surface. So if they cannot rid themselves thru radiation, as you say, of the heat then the atmosphere will continually warm? Or is convection sufficient?
I have brought this up before that we seem to ignore 99% of the atmosphere.
And the people like yourself who bring this up ignore half of the planet’s rotation, during the night the planet’s surface will cool down and will now be cooler than the atmosphere and so will cool the atmosphere by conduction.
Come on Stephen, speaking radiatively, you are brighter than that.
The context of my example was radiative energy from a Sun-warmed Surface. In that context, radiative energy from the Surface, given a non-GHG atmosphere, gets a free pass to Space and is lost forever. Given a GHG atmosphere, some of it is absorbed by the GHG (preventing it from driectly going out to be lost in Space), and some of that radiative energy emitted by the GHG is returned to the Surface.
You are correct that, for a non-GHG atmosphere, any heat energy it picks up by conduction from the surface cannot get out to Space via radiation because non-GHGs do not radiate. So, that energy can only get out by conduction back to the surface and then radiation to Space, and that effect will raise the temperature of the surface.
However, given a non-GHG atmosphere planet, the surface will be a bit cooler during the day than a no-atmosphere planet, and a bit warmer during the night. Bottom line, a no-atmosphere planet will have about the same mean temperature as non-GHG-atmosphere planet, but the latter will have more moderate swings between day and night.
Please explain to me, using FOLLOW THE ENERGY reasoning (please), how a non-GHG atmosphere planet can have a higher mean temperature than a moderate-GHG planet. Also why a richer-GHG planet will not be warmer than a moderate-GHG planet, all else being equal.
Baa Humbug,
That is an interesting scenario, but I disagree with a few things.
1) If 1/2 the world is 30 C and 1/2 is 0 C, then the outgoing radiation would average to
(315 W/m^2 + 478 W/m^2) = 396.5 W/m^2. Other distributions (eg 1/3 @ur momisugly 30C, 1/3 @ur momisugly 15C, 1/3 @ur momisugly 0Cof temperature would give slightly different numbers, but still in this ballpark. So off the bat, Esch must receive way more power than Earth. That’s fine — it has a different orbit, or orbits a hotter star.
But 396.5 W/m^2 would be the starting point, not 235 W/m^2
2) Whatever mechanism brought the planet to your hypothesized uniform temperature would have to radiate ~ 396.5 W/m^2 uniformly from all points, which would be ~ 289 K or ~ 16 C. This slight increase is due to the whole “Holder Inequality” thing related to averaging T^4 rather than averaging T.
So the planet would warm, but only by ~ 1 C to ~ 16 C, not by 15 C to 30 C.
3) If the planet actually did reach a uniform temperature everywhere, the convection would stop, causing the poles to cool and the equator to warm. The equilibrium condition would be somewhere in between these two extremes, This in turn would decrease the effective temperature a little bit from the value in Part 2 (ie 16C).
First off EVERYTHING that has a temperature above 0 radiates energy. Just because something can’t absorb IR very well doesn’t mean that if it has heat it won’t radiate. Put a hot bag of nitrogen and a hot bag of CO2 in space and they’ll get to 3K very quickly. By radiation! They’ll have different spectral signatures but they will radiate away their energy content. There’s more ways to heat a gas than absorption of IR.
If you think differently about this then please link me to a paper or reference. I’d love to read it.
Here’s another question for all. If I had a long bar of steel sitting in the shade of a tree for a long long time (humor me here) it would have some internal energy constant throughout its length. If I then observed it from the moon with super secret radiation detector I could measure its radiation emission. Correct?
Now let’s apply some temperature to its ends for a very very long time; elevating one end, while lowering the temperature of the other, such that the bar has the exact same energy content when everything settles down. My super secret moon based detector sees no change in radiation (I think). At the same time, an ordinary public knowledge radiation detector aimed at the hot end during this experiment would see an increase in radiation from the hot end. Now if my only point of reference was that ordinary detector aimed at the end I would hypothesize that the energy content of the bar has to be higher than it was before. Right?
There’s a huge paradox with the GHG warming scenario. It goes like this. Surfaced generated IR energy wades through a maze of super abundant IR transparent gas until it hits a GHG which thereupon absorbs an re-radiates it as IR, thereby warming the very same IR transparent atmosphere the energy just avoided on the way up. Its like the transparent gas is only transparent when you want it to be. All the while this is happening the energies in the transparent gases are assumed to be at 0K except where they hit a thermometer.
Let me quote Phil with Real Approval:
“A common misconception on this site, gas molecules (or atoms) are only going to emit at atmospheric temperatures as a result of vibrational/rotational transitions, Argon atoms don’t have vibrational/rotational energy levels so they can’t absorb/emit via this mechanism. Similarly homonuclear diatomics like N2 and O2 don’t have a dipole so they can’t absorb/emit via this mechanism even though they vibrate and rotate. (There are some incredibly weak bands for both O2 and N2 in the vicinity of 5μm but they are ~10 orders of magnitude weaker than CO2/H2O)”
I made the same mistake as you have done, and came to realize the error of my ways. Phil is absolutely correct – they don’t emit.
Nice example, Baa Humbug! It had me going for a while.
You assume the atmosphere will remain vertically unmixed since the warmer non-GHG gas will rise and stay there, causing a stable temperature inversion and the lower atmosphere to be the same temperature as the surface (mean 15ºC), while the upper atmosphere gets warmer (30ºC). That does not seem compatible with the winds that would be necessary for the warm tropical non-GHG gas to be continually distributed to the poles, so if the surface had mountains there would be up- and down-drafts.
In any case, assuming no vertical mixing, it seems the atmosphere is the only thing on planet Esch that is warm. The surface, according to your accounting, will remain at a mean 15ºC because you say it radiates 235 w/m2 which, according to SB equates to that mean temperature. So, the only extra warming due to the non-GHGs is in the atmosphere, which has very little heat capacity.
As I understand it, while the polar atmosphere would be warm, the polar surface would still be cold, at about 0 ºC. Given that difference in temperature, would not the polar atmosphere tend to conduct heat energy to the polar surface, which would reduce the temperature of the polar atmosphere? The tropical surface would get to about 30ºC, and, to make up for the loss of energy from the polar atmosphere to the polar surface, the tropical atmosphere would cool at least a bit below 30ºC, so there would be conduction of heat energy from the surface to the atmosphere.
Accepting a perfectly smooth planet with a circulating atmosphere in only the horizontal plane, with no vertical components, it would be a planet where the surface would be a bit warmer at the poles and a bit cooler at the tropics, as a no-atmosphere planet but still have the same mean temperature. If it rotated, the dayside would be a bit cooler and the nightside a bit warmer than a no-atmosphere planet. So, surface temperatures would be moderated and it would have a nice warm atmosphere, particularly the upper parts. Sounds like a nice place to go air ballooning (bring your own oxygen supply both for breathing and for firing the gas heating flames)!
But, please note, the mean temperatures on Esch would be equal to a non-atmosphere planet and considerably cooler than a GHG-atmosphere planet like Earth.
davidmhoffer,
I agree with pretty much all of what you said at January 4, 2012 at 3:05 pm, but this explanation still leaves you way short what is needed.
For your hypothetical world with an average of 240 W/m^2, the two most extreme cases I can semi-reasonably imagine are
1) all of the sunlight falling on 1/4 of the surface, corresponding to noontime sun on 1/4 of the world, and no sunlight on the other 3/4. Furthermore, there is no thermal conduction around the globe. This gives 960 W/m^2 = ~ 90 C for the hot zone and -273 C in the cold zone for an “average temperature” of (1*90 + 3*(-273)) = ~ -185 C = ~ 90 K
2) all of the energy distributed uniformly, in which case the temperature is 255 K = -18 C
If the atmosphere succeeded in transforming World 1 into World 2, then the non-GHG atmosphere would indeed have rasied the average temperature by ~ 170 C (while keeping the “effective radiating temperature” at 255 K the whole time.
But this leaves 2 problems
1) World 1 & World 2 are unrealistic. The extreme would is too extreme; the uniform world is too uniform. This would raise the average temperature of World 1, and lower the average temperature of World 2. The non-GHG atmosphere would create a much smaller change than 170 C.
2) More importantly, the pressure STILL has no way to raise the temperature from -18 C to 15 C. The BEST this mechanism could do is create a world with an average temperature of -18 C.
So, yes, a non-GHG atmosphere will have SOME effect at raising the average temperature, but no, it cannot raise the temperature enough. Only a GHG atmosphere can get you above and average of -18C.
davidmhoffer says:
Read this: http://wattsupwiththat.com/2011/12/29/unified-climate-theory-may-confuse-cause-and-effect/#comment-853148 , many times if you have to.
What you have just shown is why the vast majority of climate scientists talk about the “surface temperature enhancement” being 33 K and not 133 K (as Nikolov et al say it is): Those scientists understand that you can get different values by having a different temperature distribution. Hence, if you have a surface emitting 240 W/m^2 and having the distribution that Nikolov et al. talk about, the temperature will be ~155 K. If you move the heat around, you can indeed raise the average temperature up further. In fact, you can get it up to 255 K by having a perfectly uniform temperature distribtuion. But, no matter how hard you try, you are not going to get a surface emitting 240 W/m^2 to have a higher average temperature than that (for a surface with emissivity approximately equal to 1).
I think you are learning the hard way that climate scientists are a little smarter than you think and you and Nikolov might be just a little bit less smart than you think.
Phil., January 4, 2012 at 4:47 am :
That’s nonsense, Phil.
Take a blob of anything and put it in “deep space” away from anything like a star, and it will eventually cool down to a few kelvins. It doesn’t matter what it’s made of.
A planetary atmosphere is just a more complicated example of something like a “gas in a box”, where the “box” is the gravity well of the planet. This box is large, and thus the allowed energy levels for the molecules are very closely spaced, allowing for absorption and emission at very fine graduations of Kinetic Energy. Again, it doesn’t matter what it’s made of.
Learn some Physics yourself.
/dr.bill
Dear dr.bill
I made the same mistake – but what happens in deep space to your box of gas is that the gas conducts heat to the box, and the box then cools by radiation. Phil is not talking nonsense – the diatomic gases really don’t absorb. At best, they scatter and refract.
Paul Bahlin says: January 4, 2012 at 3:46 pm
“First off EVERYTHING that has a temperature above 0 radiates energy. Just because something can’t absorb IR very well doesn’t mean that if it has heat it won’t radiate. Put a hot bag of nitrogen and a hot bag of CO2 in space and they’ll get to 3K very quickly. “
Sort of … The power radiated by an object is P/A = (emissivity)(SB constant)T^4. So a sphere of highly polished silver (emissivity = 0.02) will loose energy at 1/50 of the rate of the same silver sphere painted flat black (emissivity = 1.0). The object with the high emissivity will cool “quickly”, but the object with a low emissivity will cool “slowly”.
Defining the emissivity of gasses is a bit tricky, since it depends on volume, pressure, and temperature. But under similar circumstance, the emissivity of CO2 in the IR region of interest (>4um) is orders of magnitude larger than the emissivity of N2, so CO2 will cool orders of magnitude faster. For most practical purposes, the emissivity of N2 can be considered so close to zero that it does not emit significant IR energy.
The rest of your post also contains a few errors, but I don.t have time to address it sufficiently now — sorry.
Joel
All that I admitted was additional feedbacks due to a rise in temperature from some increase in the W/m^2 variations are not ‘counted’. That is if one has a co2 doubling which changes the w/m^2 by 3.7 w/m^2, the temperature will rise due to that plus any other ‘feedback’ such as that due to the h2o vapor increase caused by an increased temperature. It was mentioned that the co2 contribution would be about 0.8 deg C rise and also that the contribution for a 2 deg C rise from h2o vapor would be on the order of yet another W/m^2 increase, making the total around 1 deg C – except that the h2o cannot contribute that much of an increase for only a 1 deg C rise – so in reality, the final T decreases below 1 deg C. However, if we leave it at 1 deg C, there are other smaller feedbacks (smaller according to the ipcc who claims the h2o vapor is the largest) which might make up for the difference.
Now, if you want to insist on there being problems because of things that don’t enter in to the considerations made for this, good luck. perhaps Anthony will set up some side thread somewhere to discuss it. BTW, that number 151 w/m^2 is not just for the ghgs but also aerosols cloud cover etc. It is the difference between what is emitted from the surface and what escapes into space. Note that there is more absorption going on that is countered by re emission outbound so it’s a wash. what is radiated is almost 2/3 of what is emitted from the surface. Small changes in values will not change this ratio.
Dr Bill,
The “gas in a box” energy levels correspond to allowed values of momentum for the gas molecules. The fact that the “box is large” means the allowed values of speed of the molecules are very closely spaced. This has nothing do do with the allowed vibrations of the molecule itself, which is what determines the IR properties (along with the distribution of charge within the molecule).
The iceman cometh says:
January 4, 2012 at 3:39 pm
“But I said if you carried out the requested experiment, and introduced some nitrogen as an atmosphere to a planet that previously had none, the planet would first cool because energy was transferred to the gas, and only then would it warm because it would revert to radiative equilibrium. Lapse rate and the effective height have nothing to do with it because our hypothetical atmosphere is not radiative at the wavelengths we are talking about. At first, therefore, the planet would emit less radiation than before it gained an atmosphere, because it was cooled, and then it would warm until it emitted just the same as before. The warm atmosphere would be the result of conduction and convection.”
I don’t really understand what you are saying here. By my logic, any process that causes the atmospheric temperature to increase will also increase the radiation of energy proportionally to T^4. In short, anything (nitrogen, CO2 whatever) that warms will radiate more energy and anything that emits more energy than it absorbs will cool. Moving heat around(or convection and conduction) can produce an overall temperature increase (as per my #1), however, even on an atmosphere conduction and convection were perfect and instantaneous (ie temperatures were completely uniform over the whole surface of the Earth) this would not add up to anywhere close to the 33K difference we experience on the Earth.
Cheers, 🙂
Hi shawnhet,
I think the mistake you make (and I made the same one, so you are not alone!) comes in:
“By my logic, any process that causes the atmospheric temperature to increase will also increase the radiation of energy proportionally to T^4. In short, anything (nitrogen, CO2 whatever) that warms will radiate more energy and anything that emits more energy than it absorbs will cool.”
Nitrogen or oxygen or argon or other symmetrical diatomic gases really do not emit. Read Phil’s post on the subject – I cannot express it better. It came as a surprise to me, but they are as absolutely transparent to radiation as you could wish. And what doesn’t absorb cannot emit (Kirchoff). So my hypothetical planet which suddenly acquires a nitrogen atmosphere will only lose heat by radiation once it is equilibrated with its new atmosphere, and its new atmosphere will not lose heat by radiation. Hope that helps.
Ira Glickstein, PhD says:
January 4, 2012 at 4:07 pm
Thankyou for replying.
No, I do assume the atmosphere will mix. That’s how the 30DegC is distributed around Esch including the poles..
I also don’t assume the lower atmosphere to be the same T as the surface mean (15DegC). I assume the lower atmosphere AT THE EQUATOR will be 30DegC, the same as the surface T.
I’d like you to think about my scenario a little longer.
We need to stop thinking about mean Ts. The equator of Esch receives enough DSWR to reach 30DegC. Inevitably, some of this energy/warmth will transfer to the air via conduction.
Since the non-ghg gasses of this air cannot radiate away it’s newly found energy, it can only shed it via conduction with the ground.
Therefore, unless it can be argued that overnight cooling via conduction is just as fast/efficient as daytime warming via conduction, the atmosphere must accumulate heat.
And the longer we allow this process to continue, the more heat will be accumulated until a maximum is reached. that maximum on Esch is 30DegC.
I contend that warming via conduction is faster than cooling via conduction because we are looking at an interface between a solid (Esch surface) and a freely moving gas which expands and rises when warmed.
That is an excellent point which gives me something to think about. The rate of transfer from atmosphere to surface at the poles would be much greater. The question then would be; Would this rate of transfer cancel out the rate of transfer at the equator. If it does, then my hypothesis is shot. However if it doesn’t, however slight, then my hypo is alive.
p.s. I’m still waiting for an answer to my Q at 8:43pm 2nd January. Respondents would be appreciated.
p.p.s. Regarding the poles, I think we would end up with permanent temperature inversion there.
Tim Folkerts says:
January 4, 2012 at 3:42 pm
Thanx for the reply Tim (I’ve read most of your comments and I appreciate your contribution)
But alas, the numbers I used (e.g. 235Wm2) were just plucked from Willisses posts. The numbers are really irrelevant at the stage my scenario is in.
Tim Folkerts, January 4, 2012 at 5:18 pm :
Tim: The momentum and energy of a particle are inextricably linked, and I mentioned neither IR nor vibrations. Where, for example, are molecular vibrations involved for the case of a monatomic gas (such as Argon)? Masses can gain or lose energy simply by gaining or losing ordinary speed. The gains and losses can involve radiation of any wavelength. That’s how we measure the “temperature” of the cosmic background, a very long wavelength indeed, right?
/dr.bill
Stephen Wilde says:
January 4, 2012 at 1:11 pm
“Redshifting means that they lose energy so that the wavelength increases and the light emitted shifts towards the red end of the spectrum.”
You have forced me to dig out old notes. The shift depends on the position of the observer with respect to the radiating object. In fact, if the radiating object is the Sun, and the observer is on Earth, there is a blue shift. Gravitational red shift is associated with a photon leaving a massive body.
In any case, photons do not release heat, and the speed with respect to coordinate time does not change. Heat results when a photon is absorbed by a massive particle. But, why are we arguing about this? That radiation is intercepted and heats the atmosphere and the Earth is not a subject of contention.
Stephen Wilde says:
January 4, 2012 at 1:47 pm
“Radiation not necessary. Non GHGs return everything they receive back to the surface before it can be radiated out by the surface.”
That may be a plausible mechanism, to some extent. But, you need to find a way to quantify it – words alone are just not going to suffice. I doubt it is very large, because there is a really large yawning gap in the emission spectrum from the planet which clearly results mostly from water in the atmosphere, and I think it is large enough to explain the lion’s share of excess heating.
“Tim Folkerts says:
January 4, 2012 at 4:54 pm ”
A really good real example is hydrogen atoms. One sees them in pink in sky when there are hot uV emitting stars radiating the hydrogen gas cloud. To go from ground state to 1st excited state requires a uV photon but once there, the atom can easily be excited to higher states that can emit visible red light – the pinkish red of the emission nebula. Even lower energy photons are possible although somewhat unlikely, requiring beginning and ending states to be rather high order. However, when one considers that the proton in the nucleus has a spin as does the electron and that there is a difference in energy states between when the spins are parallel and antiparallel, one can understand that far lower energies can be absorbed and radiated by the hydrogen atom. This is the famous 21cm microwave line which is well below the energies required for infrared.
N2 has 120 known lines in the 2-100 um wavelength range and O2 has 1397 lines. These must be compared to 56138 lines of co2 and 28673 known lines of h2o spectrum in the same 2-100 um range.
Baa Humbug,
I’m not an expert on the atmosphere, but it seems that something like Hadley Cells would still be set up on the various hypothetical worlds, resulting in continuous convective energy transfer from the equator to the poles, with a continuous temperature gradient from the poles, eliminating the possibility of a uniform temperature. I suspect there would ALWAYS be convection, with the descending air near the poles cooling toward the surface temperature of 0 C (using your numbers) as it travels along its path from the poles toward the equator. Meaning you would NEVER reach anything approximating a uniform 30 C in the atmosphere
To those who believe the energy flow balance argument disqualifies the idea of non-GHG heating, I wish again to point out my discussions with Willis at 11:57 am, 11:47 am and 11:06 am. Where is the surface? The surface of the planet is at about 290K, which S-B says should radiate at 400 W/m^2 or so. But, the top of the troposhpere is at about 220K, which would give 133 W/m^2.
There is no reason arbitrarily to pick the surface as the reference point, since the atmosphere is part of the system. If we pick the midpoint of the troposhpere, that is at 255K which, hey, presto! yields 240 W/m^2.
So, I think using SB and energy flow imbalance in the argument is invalid. For me, the major bit of evidence for the GHG theory is the huge chunk of energy taken out of the planet’s emission spectrum, which can be seen in Figure 3 here. I do not find it plausible that such a large masking of outward radiation can fail to have an enormous effect.
Bart says:
January 4, 2012 at 6:09 pm
Note: Figure 3 in the link I gave labels that gap with “CO2”, but the CO2 part of that gap is actually fairly narrow. It’s mostly water vapor.
Baa Humbug asks: “p.s. I’m still waiting for an answer to my Q at 8:43pm 2nd January. Respondents would be appreciated.”
I would say that the high emissivity coating will increase the net transfer from warm objects to cool objects. So I conclude that if the “box” is cooler than the “room” the high emissivity coating will help it absorb more energy, increasing the overall rate of temperature rise. Conversely, if the “box” is warmer than the “room”, then a low emissivity coating decreases energy loss from the “box”, also increasing the overall rate of temperature rise.