Conventional models assume increasing atmospheric CO2 warms the surface, then apply the feedbacks to the surface warming. But if feedbacks start up in the atmosphere instead, everything changes.
This is a post with big potential. A feedback the other climate models miss?
All the establishment models assume carbon dioxide warms the sky, which leads to the surface warming*, and the feedbacks then apply to the surface warming. It’s in the model architecture, the models can’t do it any other way. But what if the feedbacks don’t wait — what if the feedbacks start right away, up in the atmosphere? What if, say, CO2 warms the air, and that affects humidity and or clouds right then and there? These would be feedbacks operating on tropospheric warming, and they can reroute that energy.
Potentially, this blows everything away. If the energy blocked by increasing CO2 is merely escaping Earth through emissions from another gas in the atmosphere, like say, the dominant greenhouse gas, water-vapor, then could this explain why the effect of Co2 has been exaggerated in the conventional models?
We call this the “rerouting feedback” because when it’s harder for energy to escape to space through the CO2 pipe, this feedback would reroute it out through the water vapor pipe instead.
Put another way, as Earth emits (relatively) less energy through carbon dioxide’s favorite wavelengths, some of that blocked heat, possibly transferred through kinetic collisions, just reroutes out to space on the water vapor wavelengths instead.
No matter how many thousands of runs someone does on a conventional climate simulation, this outcome could never occur.
If this feedback is real and significant, it could explain why CO2 is not as potent as the IPCC supposes.
We will be expanding on this hypothesis in the future. It explains some anomalous observations. There are serious implications and tests we will develop.
— Jo
7. The Rerouting Feedback
Dr David Evans, 30 September 2015, David Evans’ Basic Climate Models Home, Intro, Previous, Next, Nomenclature.
In post 5 we noted that the architecture of the conventional model only allows feedbacks that are responses to surface warming, thereby omitting any feedbacks that are primarily in response to climate drivers. In post 6 we discussed where outgoing longwave radiation (OLR) is emitted from, and introduced the “pipes” terminology. Now we build on both.
This post proposes the existence of the “rerouting feedback”, a feedback in response to an increase in the CO2 concentration, where the action takes place high in the atmosphere. It is omitted from the basic sensitivity calculation because it is not a response to surface warming, and it is also omitted from the large computer models (GCMs). Represented by fC in Fig. 1 of post 5, it reduces the radiation imbalance ultimately caused by an increase in CO2 and thus the warming influence of rising CO2.
Background
For this discussion, let us suppose that all heat escapes the Earth through the four main pipes: the CO2 pipe, the water vapor pipe, the cloud top pipe, or the surface pipe (see Fig. 3 of post 6).
“How does the outgoing radiation rearrange itself among the four pipes?”
Increasing the CO2 concentration impedes the flow of OLR (or heat) through the CO2 pipe, so there is less OLR emitted on the CO2 wavelengths. The heat backs up a little, warming the atmosphere, but when steady state is resumed the total OLR is the same as it was originally because the absorbed solar radiation (ASR) is the same (ignoring the minor albedo feedbacks to surface warming).
The crucial question is: in light of the lowered OLR in the CO2 pipe, how does the OLR rearrange itself among the four pipes?
A pipe’s OLR is solely determined by the temperature of its emitting layer — the OLR in the surface pipe is determined by the surface temperature, the OLR in the water vapor pipe is determined by the average temperature of the water vapor emissions layer (WVEL) which in turn is determined by its average height and the lapse rate, and so on. Knowing the rearrangement of OLR between the pipes would allow us to know the change in OLR in the surface pipe, and thus the surface warming and the equilibrium climate sensitivity (ECS).
In the conventional model, increasing the CO2 concentration causes a sympathetic decrease in OLR in the water vapor pipe, due to amplification by water vapor feedbacks — the influence of extra CO2 is represented as a forcing, equivalent to extra ASR, which warms the surface, causing more evaporation and more water vapor, which presumably causes the WVEL to ascend because there is more water vapor in the atmosphere, whereupon the WVEL is cooler, which reduces the OLR in the water vapor pipe. So, in the conventional model, the surface and cloud top pipes must compensate for decreases in OLR in both the CO2 and water vapor pipes, by increasing their combined OLR by a matching amount. Obviously this requires much more surface warming than if the water vapor pipe also increased its OLR in response to the decreased OLR in the CO2 pipe.
Sketch of the Mechanism
Increased CO2 causes a decrease in OLR in the CO2 pipe. Now consider how it might also trigger a feedback that increases OLR in the water vapor pipe, by way of partial compensation (as if fC in Fig. 1 of post 5 was negative).
From the point of view of heat in the upper troposphere, increased CO2 makes it harder to escape to space in photons fired from CO2 molecules, and therefore relatively easier to escape in photons fired from water vapor molecules. Increased CO2 thus increases the relative propensity of OLR to come from water vapor molecules. The energy has to escape to space somehow, the relative attractiveness of the CO2 pipe has decreased compared to the water vapor pipe, and the heat is essentially available to all molecules because they swap energy back and forth by thermal collisions. Furthermore, the changes in the CO2 spectrum with increased CO2 occur in the wings of the CO2 “well” (see for instance the last diagram on this page of Barrett Bellamy), at heights around 8 km, which is about the average height of the WVEL.
“…when increasing CO2 makes it more difficult for heat to radiate to space on the wavelengths at which carbon dioxide absorbs and emits, some of the blocked heat simply reroutes out to space on the water vapor wavelengths instead.”
If more OLR comes from the water vapor molecules, the population of water vapor molecules would be less energetic and would thus tend not to ascend quite so high in the Earth’s gravitational field — so the WVEL would descend slightly (which would be compatible with the non-observation of the “hotspot”; more on that in later posts). Although the population is less energetic, the top of the population is in a lower and therefore warmer place compared to it where was before the increased CO2 caused it to descend. Thus the WVEL is warmer, emitting more OLR.*
Note that it is possible for the WVEL to descend despite increased evaporation from the surface, if the extra water vapor is mainly confined to the lower troposphere and the consequent greater stability at low altitudes leads to less overturning and less transport of water vapor to the upper troposphere — indeed this seems to be happening, as reported by Paltridge et. al in 2009 [1], from study of the better radiosonde data from 1973.
We call it the “rerouting feedback” because some fraction of the OLR that is blocked from escaping to space out the CO2 pipe by rising CO2 levels is instead rerouted out the water vapor pipe.
“It is not a response to surface warming, but to CO2 enrichment.”
In other words, when increasing CO2 makes it more difficult for heat to radiate to space on the wavelengths at which carbon dioxide absorbs and emits, some of the blocked heat simply reroutes out to space on the water vapor wavelengths instead. This feedback takes place high in the atmosphere, far from the surface, so there is no place for it in the conventional climate model — which only contains feedbacks in response to surface warming.
This proposed feedback is contained within fC in Fig. 1 of post 5. It is not a response to surface warming, but to CO2 enrichment. It all occurs within the higher atmosphere, so it responds more strongly to variables describing the upper atmosphere and radiation than to the surface temperature. (Perhaps a suitable variable to describe the strength of the feedback is the height of the CO2 emission layer plus the height of the WVEL.)
The rerouting feedback might offset a substantial portion of the reduction in OLR in the CO2 pipe due to an increasing CO2 concentration. If it exists, the rerouting feedback would lower our estimates of the sensitivity of surface temperature to rising CO2 levels.
A Negative Feedback?
The rerouting feedback reduces the ultimate radiation imbalance due to extra CO2, so it is a negative feedback in terms of its effect on the CO2 forcing, so fC is negative. Applying the feedback diagram in Fig. 1 of post 3 with a equal to DR,2X and b to fC, the rerouting feedback changes the radiation imbalance due to increasing CO2
For example, if fC was −0.6 then
and the influence of increasing the CO2 concentration would be reduced by 70%.
Semantic point: Although the rerouting feedback reduces the sensitivity of the surface temperature to changes in CO2, and although fC is negative, it is not a feedback in response to surface warming so it is not a “negative feedback” as that term is understood in the conventional paradigm.
Energy Considerations
Consider how the climate might adjust to a decrease in OLR in the CO2 pipe. The blocked OLR has to find its way to space somehow. The resistance of the surface pipe to carrying more OLR is exceptionally high in the tropics, where most of the heat is, because heat loss from the surface via evaporation rises exponentially with surface temperature (Kininmonth 2010 [2] elaborates on this). The resistance of the water vapor pipe to carrying more OLR might be relatively low, because it requires only that the average height of the WVEL (~8 km) ascends or descends by a few tens of meters. Like the WVEL, the cloud tops might ascend or descend slightly with little apparent energy requirement.
The energy required to warm the surface on a sustained basis, with the ocean warming that would entail, might be much greater than the energy required to change the average height of the WVEL or cloud tops sufficiently to change OLR by the same amount. (More research is needed to get the figures to assess this.) This would suggest that the bulk of the response to the decrease in OLR escaping via the CO2 pipe would come as more OLR from the WVEL or cloud tops, rather than from the surface — which is consistent with the proposed rerouting feedback and with a lower ECS.
Figure 1: Electrical analogy for heat escaping to space. The zig-zags are electrical resistors; the current (a la heat) mainly flows through the paths of least resistance — the current in a resistor is inversely proportional to its resistance. Increasing CO2 increases RC, so some current reroutes from flowing through RC to flowing through the other resistors, mainly through the other resistor with the lowest resistance.
* Update 4 Oct 2015: The mechanism sketch needs more details, as discussed in the comments (thank you Stephen Wilde and Joe Born).
If less heat is escaping to space from CO2 molecules, the upper atmosphere must warm, especially the upper troposphere where the most significant changes in the emissions spectrum of CO2 are occurring, in the wings of its 15 micron “well”. Presumably this heat warms the WVEL, also in the upper troposphere, and so more OLR is emitted from water vapor molecules. Hence the rerouting of some OLR from the CO2 pipe to the water vapor pipe, as CO2 increases.
How would this affect the height of the WVEL? If the lapse rate remained unchanged, it would have to descend in order to be warmer, so presumably it would descend — somehow (knowing the initial and final states doesn’t necessarily tell us how it did it).
However an offsetting mechanism could be as follows. There is a net loss of emission of heat to space as OLR (the increase from water vapor could never compensate for the decrease from CO2 100%, though it might be close-ish), which would change the local lapse rate, in the upper troposphere. OLR accelerates the cooling of ascending air, so the net decrease in OLR would decrease the lapse rate a little (that is, less cooling per kilometer). A decrease in the local lapse rate means it’s warmer at the same altitude, working upward from a surface at a constant temperature, so perhaps a warmer WVEL could be found at an unchanged altitude.
(The warmer WVEL would mean the water vapor population is more energetic, more able to work against the Earth’s gravity — even though it is losing energy via increased emission of OLR, there is a net increase in energy in the water vapor. So this factor would tend to increase the WVEL height slightly. However this is presumably a much smaller force than lapse rate and humidity changes.)
Paltridge et al. [1] note that the last few decades has seen a drier upper troposphere, which they explain as the extra water vapor due to surface warming creating greater stability at low altitudes, leading to less overturning and less transport of water vapor to the upper troposphere. Perhaps increased CO2 is also leading to a slightly drier upper troposphere, which would lower the WVEL.
References
[1^] Paltridge, G., Arking, A., & Pook, M. (2009). Trends in middle- and upper-level tropospheric humidity from NCEP reanalysis data. Theoretical and Applied Climatology, 98:351-359.
[2^] Kininmonth, W. (2010). A Natural Constraint to Anthropogenic Global Warming. Energy and Environment, Vol. 21, No. 4, 225 – 236.
*Yes, this is shorthand. In a technical sense, CO2 is not “warming” the ground, merely slowing heat loss while the Sun sends in more energy. Ultimately the ground ends up warmer than it would have been.
Sounds like a perfectly reasonable suggestion to me. But surely all those highly paid, mega-intelligent climate scientists out there haven’t totally missed this possibility in the past. Assuming that’s the case, I’m wondering what rationale have they offered for dismissing its validity?
Or is my assumption incorrect?
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It’s in their blind-spot, Rodzki.
The proposed phenomenon is obviously not a “forcing”, and nor is it what they call a “feedback” (because their “feedbacks” are only in response to surface warming). Being neither forcing or feedback, it doesn’t exist in the conventional paradigm.
This is the first example in this series where architecture matters. There is no place in the conventional architecture for this feedback (in the true meaning of that term, used by everyone else except some climate scientists). But if it exists, as seems reasonable, it changes everything, big time. We later show some circumstantial evidence that it, or something akin, does in fact exist.
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Paradigm shifts typically result in a physically measurable redefinition of terms.
For example, the term “Time” is constant in the Newtonian paradigm and relative in the Einsteinian paradigm.
The mainstream climate paradigm does not map to real world observations, hence it must be flawed. A new paradigm that includes new and/or redefined terms will enable a new attempt to understand actual observational data.
For me, what will be critical will be two elements.
[1] Novel predictions of measurable observations that can be made based on your new paradigm, and
[2] The ability to straight forwardly explain previous anomalous readings that can only be treated in an ad-hoc way within the current paradigm.
Great work btw.
Thanks for all your efforts with this.
Cheers ExWarmist
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Both elements coming up later in the series.
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David,
For what it’s worth, if more CO2 restricts emissivity (and I have every reasons to expect it doesn’t) then the excess heat in the troposphere is more likely to change albedo and emission through the surface atmospheric window by evaporating clouds.
Of course evaporating clouds doesn’t change temperature, just latent heat.
I need to point out what I’ve said before again, when an IR photon impinges on a CO2 molecule it will cause a bond vibration (excited electron within a bond), it does not cause a translational energy increase (thermal change). Save any collisions with surrounding N2 or O2, that molecule WILL reradiate that photon at some future time regardless of its thermal temperature, what goes in must come out. If we are discussing an IR flux then we must recognise this.
The only way colder CO2 has reduced IR output is because the probability of a collision with O2 or N2 around it, with sufficient energy to raise the bond energy so that a photon can be emitted is lower.
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A molecule cannot reradiate a photon of the same wavelength that it absorbed. This is because photons have momentum, Unless the photon was emitted in exactly the same direction (p= 1/infinity) the conservation of momentum would be breached. When a molecule reradiates energy it does so typically in a series of steps and possibly some residual thermalisation. Increased temperature also reduces the ability of GHG to absorb energy due to a reduction in the number of unexcited molecules. (increased temp flattens and broadens the absorption curve). This is a basic experiment performed in first year chemistry on carbon monoxide, yet climate scientist just don’t seem to get the concept that the concentration of a chemical increases the rate of reaction, both absorption to thermalisation and de-thermalisation to emission. Increased CO2 must both reduce emissions from the surface to space (in the non saturated wing) while increasing emissions from the atmosphere to space, particularly at the tropopause where the cold temps make the proportion of emission in the CO2 wavelength relatively larger.
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Increasing CO2 reduces emissions to space from CO2 molecules, because the effect you outlined is outweighed by the cooling of the CO2 emission layer at wavelengths in the wings of the Co2 “well” centered on 15 microns (cooler objects emit less).
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Rob JM
Yours is an interesting comment and very perceptive. The momentum of an infrared photon, p = h/wavelength = 6.6 x 10^(-34)/(15 x 10^-6)or 9.9 x10^-27 against the mass of a CO2 molecule of 44 x 1.6 x 10^-27 =70.4 x 10^27 will change the velocity of the molecule by about 0.1414 m/s. Thus the Doppler change, df, in the maximum emitted frequency f – i.e. for a photon emitted back towards the direction of the source of the original photon, will be approximately df = f*v/c = ~2 x 10^13 x 0.141/(3 x 10^8) Hz = 9 x 10^3 Hz which is a factor of about 10^5 less than the collision induced line width so does noy produce a very significant effect.
However, your comment is relevant in that it draws attention to the fact that for radiation escaping upwards, the linewidths at lower levels are broader (collision broadening is higher in the denser lower layers) than those above so that radiation from the extremities of each line are impeded less in the layers above, providing for the escape of more radiation, while for the radiation back to earth, the reverse is true – down radiation is more highly impeded. For the Doppler broadening component, this is also wider in lower, warmer layers, leading to the same effect. Another factor with similar repercussions is that as the density of CO2 increases, while the downwards radiation from a sample of air will increase, the layers below will be more highly absorbing partially at least counteracting the effect of the increase in CO2 and reducing the suggested warming of the earth by this “back radiation” which is so emphasized by Hansen and displayed vigorously in his famous diagram.
John Nicol
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David
For the CO2 restricted OLR to leave via the H2O pipe it would not have to be of a wavelength that would cause it to absorbed by the H20 molecules which I believe can overlap those of H2O. Is that so? If not how does is preferentially escape that way?
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Energy can be transferred from the CO22 molecules to the water vapor molecules either because of overlapping absorption wavelengths (CO2 and water vapor share some wavelengths) or by thermal collisions.
The thicker CO2 blanket alters the relative ease of producing OLR, shifting the preference slightly from CO2 to water vapor.
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do you take into account the fact that water gas is the lightest gas (of consequence) in our atmosphere and rises to the top regardless of temperature?
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David: Your proposed “re-routing” feedback may be part of Planck feedback (or Planck response comprising no-feedbacks climate sensitity). Planck feedback results in the emission of an additional 3.2 W/m2 of OLR to space for each degK of warming. Only 10% of the photons emitted by the surface escape directly to space – about 39 W/m2. If surface temperature rises 1 degK, the direct to space emission rises only 0.5 W/m2, since total surface emission rises to 395 W/m2. Where does the other 2.7 W/m2 of Planck feedback originate? The logical answer: GHGs in the atmosphere, mostly water vapor!!!
How can surface warming increase emission from the atmosphere? When calculating the No-feedbacks climate sensitivity and Planck feedback (or Planck response), we assume the planet is a blackbody at 255 degK, the simplest model that explains why the earth emits 240 W/m2 of OLR to space (and absorbs the same amount of SWR). In reality, of course, that emission comes mostly from GHGs in an atmosphere with temperature ranging from 210 to 310 degK and a little comes from the surface. Raising the blackbody temperature from 255 to 256 degK produces the calculated Planck feedback of 3.2 W/m2. 2.7 W/m2 of that is emitted by the atmosphere and 0.5 W/m2 is emitted by the surface.
If you account for the rise in emission from GHGs with temperature twice – once as Planck feedback and once as re-routing feedback – you will get a very low climate sensitivity.
Perhaps now you recognize the advantage of calling Planck feedback “Planck response”. Unlike typical feedbacks, it isn’t calculated based on a rise in surface temperature. It uses a blackbody model for the planet and a blackbody equivalent temperature, which is mostly the average temperature of GHGs in the atmosphere. When they warm, they produce most of the Planck response. The Planck response is modified by feedbacks.
AOGCMs don’t rely on the concept of Planck feedback and other feedbacks. They will properly calculate radiation transfer at each grid cell based on its expected temperature and composition. In the emission term of the Schwarzschild equation used by AOGCMs, the Planck function B(lambda,T) produces the same Planck response as a blackbody model.
As a skeptic of the consensus, I would prefer to be wrong. As a scientist, this seems right. Respectfully, Frank.
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Frank, no the rerouting feedback is not part of the Planck feedback/sensitivity.
The Planck feedback is estimated under the Planck conditions — namely all but OLR and surface temperature are held constant, tropospheric temperatures change uniformly, and the stratosphere stays constant (see post 2). Thus the CO2 is held constant. But the rerouting feedback is a feedback in response to increasing CO2, so it is not occurring in a Planck feedback estimate.
In other words, the Planck feedback is how much OLR increases per K of surface warming, holding all else constant — including CO2. But the rerouting feedback is a response to increased CO2, so the rerouting feedback is not part of the Planck feedback.
All the water vapor variables are also held constant under the Planck conditions, except for its temperature. Sort of silly to arbitrarily hold only some variables constant — which is the essence of my complaint about the partial derivatives in the conventional basic model, in post 4.
The Planck feedback is 80% due to Stefan Boltzmann, then most of the remainder is a correction due to some GHG emissions originating in the stratosphere (most of the CO2 band, and ozone) — which does not warm as the surface warms under the Planck conditions. There is also a minor correction for the uneven distribution of temperature around the globe (emission are T^4, strongly concave). No CO2 changing or rerouting here.
I agree that the “Planck feedback” is a misnomer — see post 2. We use “Planck sensitivity” (its reciprocal) almost exclusively in this series. Also agree with calling it a “response” — see Fig 2 of post 3, where the Planck sensitivity and the feedback loop form the yellow box labelled “Response”.
While AOGCMs don’t use the Planck sensitivity and the feedbacks like the basic model, they do share two architectural flaws with the basic model. One is the omission of feedbacks in response to changes other than surface warming, of which the rerouting feedback here is an example.
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David,
I believe that it is patently obvious from the “hard” geological and ice records that the overall feedback to CHANGES in temperature MUST be negative, otherwise the stability in global climate which has persisted for thousands, no, millions of years would not have been possible. It is much like the feedback in a radio set which keeps the chosen volume of sound constant.
The limits to lower temperatures could obviously be closely related to maximum insolation, although there may well be feedbacks which come into play at lower temperatures tending to return the whole system to the mean value of say 287 K or whatever from lows of 279 or so.
In the present situation in which we will assume for the moment that increases in atmospheric CO2 May cause warming of the planet, including the oceans, this would have the effect of increasing free CO2 by means of dissolution from the sea irrespective of the known additions from burning fossil fuel. If CO2 is the major driver of any warming, then this in itself would have to provide a dominating positive feedback, leading to continued heating. However, since the earth has NOT continued to warm significantly since the last ice age even in the periods of a high level of solar activity, I believe that the net feedbacks MUST always be negative, as you are indicating.
Further also to your comments about the feedback through water vapour in the upper troposphere causing cooling, since the heating of the air through absorption by carbon dioxide is a feature of the surface temperature, and that absorption causes a higher temperature in lower level samples of air with less IR heating at higher levels because of the “earlier” absorption, there will be 1. Enhanced convection and circulation and 2. the cooling mechanism through water vapour you mention will indirectly become a feedback against surface temperatures through the resultant cooler air, with higher circulation rates, eventually falling to earth and cooling that surface. i.e. the feedback you refer to in the upper layers might well be thought of as a feedback relative to surface temperatures, I believe. Cheers, John Nicol
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David wrote: “In other words, the Planck feedback is how much OLR increases per K of surface warming, holding all else constant — including CO2. But the rerouting feedback is a response to increased CO2, so the rerouting feedback is not part of the Planck feedback.”
To a first approximation, 2XCO2 can’t cause re-routing feedback through enhanced emission from water vapor without first causing a rise in temperature. The only factors that directly control emission from water vapor are temperature and absolute humidity. Rising humidity is a known feedback. Rising temperature causes Planck response, which I have proven above is generated mostly through increased emission by GHGs is the atmosphere. (A second approximation would include overlapping absorption bands, and 2XCO2 blocks some absorption by wave vapor.)
In your reply, you say that Planck response is generated under “Planck conditions” and discuss the surface, troposhere and stratosphere. Calculation of the Planck response is totally ignorant of all of these factors. The calculation assumes that the planet is a box box that emits like a blackbody at 255 degK. It does not hold other factors constant – there are no other factors in the calculation! When we treat the whole planet as a black box, we can’t say where the 3.2 W/m2/K of Planck resonse comes from and what phenomena must be accounted for by other feedbacks (partial derivatives). By looking at more sophiticated calculations, we know that most of the 3.2 W/m2/K of Planck response from this black box arises from GHGs in the atmosphere, the same location as your re-routing feedback. Both Planck resonse and re-routing feedback are emitted by warmer water vapor in the atmosphere! You appear to be accounting for this twice.
(This account is done by the emission term of the Schwarzschild equation for GHGs in the atmosphere and the emission from a blackbody – both of which contain the Planck function integrated over all wavelengths.)
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Frank, while temperature and humidity control water vapor, “temperature” needs qualification. The temperature of the water vapor emissions layer (WVEL) is influenced by a CO2 build up. This is a local temperature, high in the atmosphere, and is not necessarily linked to the surface temperature. It may affect local lapse rate — the lapse rate of the upper troposphere for instance, without impacting surface temperature. The rerouting feedback is a response to Co2 enrichment, not surface temperature — a working definition might be the increase in OLR that occurs when CO2 increases that is not dependent on surface temperature.
Yes Frank, the black box in the Planck feedback computation is Stefan Boltzmann. Yes, it does hold everything constant except OLR and surface temperature — consult references given in earlier post (eg Soden and Held 2006).
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David wrote: “The temperature of the water vapor emissions layer (WVEL) is influenced by a CO2 build up. This is a local temperature, high in the atmosphere, and is not necessarily linked to the surface temperature.”
Planck response is calculated for at blackbody at 255 degK, not surface temperature. (Some people calculate the Planck response for 288 degK or 288 degK plus an emissivity of about 0.6 and they get the “wrong” answer for the Planck response and the no-feedbacks climate sensitivity. “Wrong” means different from the IPCC value of 1.15 degK/doubling and 3.2 W/m2/K. Try it.) If you use 3.2 W/m2 for the Planck response, the value is based on the temperature high in the atmosphere where the average photon escaping to space is emitted. Since water vapor is the most important GHG, most of the Planck response is originates in what you call the WVEL.
Thanks for continuing the conversation.
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Check out those sources Frank, e.g. S&H 2006, pp. 3356: The Planck sensitivity/response, pdT / pdR, where T is the surface temperature and all tropospheric temperatures change uniformly, is calcuated for constant WVEL and constant everything else. It is not some mystical computation in which the climate is simulated in full; it is a simple estimate of a partial derivative, holding nearly everything constant. This is also clear from the model derivation, such as in posts 2 and 3.
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David Evans October 4, 2015 at 1:40 pm
“Check out those sources Frank, e.g. S&H 2006, pp. 3356: The Planck sensitivity/response, pdT / pdR, where T is the surface temperature and all tropospheric temperatures change uniformly, is calcuated for constant WVEL and constant everything else.”
Why should there be some constant anything in this Earth’s atmosphere? Why do you assume that the surface is radiating anything? There is sufficient spare airborne water condensate that should the surface radiative exitance somehow reduce to zero The atmosphere itself can still reduce the temperature of the whole tropospheric column even further. This process has been totally ignored. That is the basic error in the models.
All the best! -will-
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David: Thanks for the reference, attempting to understand the root of differences, and prompting me to find some mistakes in what I wrote above.
S&H calculate Planck response using climate models, raising the temperature EVERYWHERE by 1 degC, and holding everything else constant. OLR in all models rises 3.2 (3.13-3.26) W/m2, giving a no feedbacks climate sensitivity of 1.15 degK for 2XCO2 (assuming the forcing for 2XCO2 is 3.7 W/m2). This is the best value for Planck response. Climate models also tell us that only 10% of the photons emitted by the surface escape directly to space so most of this 3.2 W/m2/K of Planck response must be emitted by GHGs in the warmer atmosphere, like your proposed re-routing feedback.
Unfortunately, I had been thinking about how one calculates Planck response in the absence of AOGCMs or if you don’t trust these models. We know the earth emits like a blackbody at 255 degK. At 256 degK, it would emit 3.8 W/m2 more; a no feedbacks climate sensitivity of 0.98 degK. A reasonable approximation. The difference probably arises from the difference between the average of T raised to the fourth power and T^4 averaged.
If one performs the same calculation for surface temperatures of 288 and 289 K, the difference is 5.5 degK; a no feedbacks climate sensitivity of 0.68 K. Significantly different from AOGCMs. If one uses a surface temperature of 288 and 289 and an emissivity of 0.615, the difference is 3.3 degK. Much closer to value from AOGCMs, but average surface emissivity is over 0.9. This model doesn’t make physical sense.
So where does this leave us. I was misleading in some minor details, but none that suggest that Planck response originates mostly at the warmer surface rather rather than the warmer atmosphere, where your proposed rerouting feedback originates. Is rerouting feedback merely part of Planck response to warming or does it have a separate existence?
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Frank: In the absence of AOGCMs it is quite easy to compute the Planck sensitivity (response) and we do it later in the series. It consists mainly of SB, as you noted, then a moderate correction for the fact that CO2 and ozone mainly emit OLR from the stratosphere (stratospheric temperatures are held constant, instead of rising like everywhere in the troposphere under the Planck conditions — look carefully!), and, as you note, a minor correction for the concavity of T^4.
Yes of course much of the Planck response involves more OLR from the tropospheric emission layers — that’s exactly where most OLR comes from, and warming the troposphere creates more of it. However, the rerouting feedback is in response to increased CO2, and CO2 is held constant (“S&H calculate Planck response using climate models, raising the temperature EVERYWHERE by 1 degC, and holding everything else constant.”). Therefore the Planck response does not involve the rerouting feedback — it has a separate existence.
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David wrote: “Yes of course much of the Planck response involves more OLR from the tropospheric emission layers — that’s exactly where most OLR comes from, and warming the troposphere creates more of it. However, the rerouting feedback is in response to increased CO2 [not increased temperature], and CO2 is held constant.” Words in brackets added by Frank.
Your pipes analogy suggests that CO2 can direct more heat out the water vapor pipe without raising temperature. You call this re-routing feedback. IMO, there is no mechanism by which 2XCO2 can have an effect on water vapor not mediated by temperature. The lower atmosphere is in local thermodynamic equilibrium and emission from water vapor therefore depends only on the amount of water vapor and its temperature. (If LTE didn’t exist, overlapping absorptions might permit 2XCO2 to interfere with radiative excitation of water vapor, not enhance it.)
Thanks to your patience, this paragraph defines the scope of our disagreement: Is there a direct mechanism by which re-routing feedback can enhance emission from water vapor independent from warming? (We both appear to agree that warming of water vapor is accounted for by Planck response.)
If there were a direct mechanism by which 2XCO2 could stimulate emission from water vapor, the climate science establishment would consider this to be part of CO2 forcing (quantified by radiative transfer calculations and reported in W/m2 per doubling of CO2), not a feedback (mediated by warming and measured in W/m2/K). When I discussed this issue earlier, you preferred your own [non-conventional] terminology, and I deferred to your right to define your own terminology in your blog posts.
AOGCMs certainly assume LTE in the lower atmosphere and don’t include a mechanism for CO2 to transfer heat directly to water vapor without raising the local temperature. If such a direct mechanism exists the models would be wrong. (Presumably we both agree that models calculate local temperature change mediated by absorption – emission + convection.)
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Will wrote: “Why should there be some constant anything in this Earth’s atmosphere? Why do you assume that the surface is radiating anything? There is sufficient spare airborne water condensate that should the surface radiative exitance somehow reduce to zero The atmosphere itself can still reduce the temperature of the whole tropospheric column even further. This process has been totally ignored. That is the basic error in the models.
The surface and atmosphere are in LTE, which means that they emit radiation in a temperature-dependent manner that is independent of the local radiation field or convection. Therefore we can calculate how radiation traveling through the atmosphere is modified by absorbing and emission of photons by GHG’s without worrying about how other phenomena influence anything besides the local temperature and humidity. Climate and weather are extremely complicated and can’t be modeled without dubious parameterization, but its radiative component is fully understood and tractable.
It isn’t clear to me why skeptics like you waste time complaining about radiation – something we do understand – and don’t complain about serious problems – model validation, unforced vs forced variability, excessive sensitivity to aerosols in models, growing disagreement between model predictions and observations, etc. David is trying to deal with some of these issues without overturning science that has been accepted and tested for a century. The GHE isn’t a hoax, but predictions of catastrophe may be.
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Frank:
“We both appear to agree that warming of water vapor is accounted for by Planck response.” Nope. The Planck response is for a hypothetical situation where all is held constant except tropospheric temperatures and OLR. CO does not change, so there is no rerouting feedback — it is a response to increased CO2.
“…there is no mechanism by which 2XCO2 can have an effect on water vapor not mediated by temperature.” Obviously. But the point is that it can happen without affecting the surface temperature. High in the upper atmosphere, less OLR from CO2 could cause local warming which could cause water vapor to emit more. Note that temperature is involved, but not surface temperature. The conventional architecture omits feedbacks other than in response to surface warming.
Yes, the rerouting feedback could be incorporated into the CO2 forcing, a la post 5, but such feedbacks are omitted from conventional models. If I were in charge of a GCM and wanted to include it, I would do as implied by fig 1 of post 5, with fC.
Here the term “feedback” is used as per throughout science and engineering (as a response that can be to anything, so long as it feeds back and affects what caused it), and not in the narrow sense used in climate science where it has come to mean “a response to surface warming that affects radiation imbalance”.
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David Evans October 5, 2015 at 4:39 pm
(Frank:“We both appear to agree that warming of water vapor is accounted for by Planck response.”)
“Nope. The Planck response is for a hypothetical situation where all is held constant except tropospheric temperatures and OLR. CO does not change, so there is no rerouting feedback — it is a response to increased CO2.”
Please can you show physically any temperature response at any location to increasing atmospheric CO2 ppmv?
You like the Climate Clowns, have nothing measurable, only some opposing fantasy.
OTOH All the best! -will-
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Frank,
As David has pointed out, radiation to space from the upper atmosphere is not freom a single layer but is a composite of fields emitted over a long range of heights – practically nothing from the ground at Green House Gas wavelengths, but slowly increasing in “escaping” photons as one goes higher and higher. For this reason, reference to the Planck radiation formula which is commonly cited is totally inappropriate for two reasons: 1. The Planck formula is non linear in frequency and is only expected to be representative of the field in “Thermal Equilibrium” which the atmosphere patently is not and 2. Adding two Planck distributions for different temperatures (from different heights) will NOT result in a Planck distribution.
The only useful way to estimate the frequency distribution and intensity is to simply determine the radiation from each very thin layer through the formula A*h*v*N/6 where A is the Einstein A coefficient (about 1.5 for CO2 at 15 microns), h is Planck’s constant, v is the IR radiation frequency and N is the number of molecules in the excited state. The absorption of that radiation from each layer to the “space” where no more CO2 exists, musty also be calculated. In this way one can arrive at an intensity of radiation which is very close to that measured by the satellites and which they relate to about 220 K implying perhaps that 220 K is the temperature of the radiating gas, which is quite obviously not necessarily so. The idea of a “radiating” and its consequences are quite incorrectly quoted by many climate scientists as implying a reason for global warming from increases in CO2. Again this is patently incorrect.
John Nicol
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John: Planck’s Law is derived postulating radiation in equilibrium with its surroundings – originally black cavities with a pin hole exit for sampling that radiation. In the atmosphere, some stronly absorbed wavelengths of LWR are in equilibrium with the local temperature at low alitudes, but equilibrium becomes impossible as the atmophere thins with altitude. You cite an unfamiliar approximation for dealing with this problem. The rigorous method for a non-scattering atmosphere in LTE is the Schwarzschild eqn:
dI = n*o*B(lambda,T)*ds – n*o*I_0*ds
My comments are based on this physics, not miappliying equations for black or gray bodies to layers of the atmosphere. You can read more about the little-discussed Schwarzschild eqn at at Bartram and Bellamy’s website, scienceofdoom, or Grant Petty’s $40 text “A First Course in Radiation Physics”. It is used for most “radiative transfer” calculations.
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Thanks for your response Frank. The formula I quoted was simply the first component of the Schwarzschild expression given in a different form – this gives the radiation from a sample. The second component (-n*o*l-o*ds) in the formula you have written represents the “absorption” I referred to for radiation escaping to space.
The accurate application of the Schwartzschild equation to radiation transfer is quite difficult in practice particularly in a system which is not in dynamic equilibrium such as the atmosphere, the temperature of which is changing for many reasons including that it is absorbing some of the radiation passing through it, which itself has a temporal variation.
As you would know, in the development of Planck’s Law, the calculation includes the number of allowed modes per unit frequency interval (standing waves) in the cavity, per unit volume. Indeed a free gas has to be very dense in order to even approximate such a system and involves the concept of “radiation trapping” which is present in the atmosphere, up to quite high levels actually, since if you consider a mass of air, containing GHGs, which is say 250 m x 250m x 250 m, most of the radiation, the wavelengths of which lie within the width of the spectral lines making up the absorption band, are absorbed again within a few metres of the radiating molecules. Thus most of the radiation is effectively trapped within the sample until it rises from convection to a height where the gas density drops sufficiently for the radiation to begin effectively “escaping”, a process which increases progressively as the sample rises. (radiation trapping is easily observed in the laboratory by directing a tuned laser into a gas which strongly absorbs the light. No light emerges from the sample which might be only a few mm thick. While the energy will eventually escape – according to the Schwartzschild equation, it escapes too slowly to provide any visible brightness.
John Nicol
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John wrote: “The second component (-n*o*l-o*ds) in the formula you have written represents the “absorption” I referred to for radiation escaping to space.”
Frank adds: Whenever GHGs absorb in the atmosphere they also emit. You can’t have one without the other. In a laboratory spectrophotometer with lamp filament at several thousand degK, we can make emission negligible, which prompts errors elsewhere. Emission of thermal infrared is always significant atmosphere where absorption of it is important. This is what makes hand waving about “trapping” so dangerous.
John wrote: “As you would know, in the development of Planck’s Law, the calculation includes the number of allowed modes per unit frequency interval (standing waves) in the cavity, per unit volume. Indeed a free gas has to be very dense in order to even approximate such a system.”
My understanding of classical radiation is poor, so I prefer the QM/photon perspective. Many absorption/emission cycles are needed for I_0 to reach equilibrium between temperature-dependent emission and and I_0-dependent absorption and eventually resulting in blackbody intensity. Same physics, different words.
John wrote: “radiation trapping is easily observed in the laboratory by directing a tuned laser into a gas which strongly absorbs the light. No light emerges from the sample which might be only a few mm thick”.
WIth a visible laser, the absorbing medium is too cold to emit at a visible wavelength, and absorption and emission of visible photons never come into equilibrium. That could be called “trapping”. Trapping doesn’t occur at infrared wavelengths in the atmosphere, because it is warm enough to emit infrared photons. Now energy can’t be “trapped” (but the alarmist want us to believe it is.) The Schwarzschild eqn still predicts a reduction in OLR with an increase in GHGs, but existence of this GHE depends on temperature decreasing with altitude.
A laser may also be misleading, because the lower atmosphere is in LTE – collisions redistribute energy through all kinetic, vibrational and rotational states much faster than an excited state emits a photon. This means that emission is determined only by the local temperature through B(lambda,T) and does not depend on the local radiation field (through phenomena like “re-emission”). There are many phenomena where emission does not depend only on local temperature (lasers, fluorescent lights, stimulated emission), but they aren’t important in the lower atmosphere where climate originates.
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Frank,
Thanks very much for responding to my comments. I give here a few sentences which are further to my earlier comments and in response to your last posting:
I am not sure what you mean by saying that “hand waving about trapping is dangerous”. The facts are well understood and fairly simple calculations show that radiation at around 15 microns absorbed into a dense atmosphere of carbon dioxide will struggle to move very far once it is absorbed. The point is also that while collisions do remove the energy from excited molecules as well as causing collisional excitation, they are also instrumental in effecting the spectral line width, which also contributes to the complexity of analysis of radiation transfer. Nevertheless, on average, the escape of a photon at the the “most probable” frequency in the centre of a spectral line which is one of the 100 or so which contribute significantly to the main 15 micron band, will also be reabsorbed by another molecule within about a metre. Photons across the wings of the lines will go further. These are very small distances compared with the region covered by a heated air mass over the tropics. So essentially the energy from that absorbed radiation, as well as the energy added to the sample through contact with the earth, emphasized by turbulence and wind over the surface interface, is virtually “trapped” within the sample giving rise to heating and subsequent convection. Convection is often overlooked as a very potent component in energy transfer from the ground level to heights where radiation from the sample can occur to even higher levels. If a sample of air is warmed by 1 C through conduction from contact with the earth of absorption of radiation, the additional energy associated with 1 cubic metre is W = 2.5 x10^25x 1.38 x 10^-23 = 3.45 x 10^2 or 345 W m^2. If this induces a slow rise of say 3.6 km /hour for the heated sample, equivalent to 1 m/second, the power or intensity of the upward transfer of energy is 345 W/m^2. For a 10 C rise, as is a most common, minimum, change in the trropics and mid lattitudes, the intensity equivalence is 3,450 W/m^2 as compared with the maximum solar insolation in the tropics of 1,368 W/m^2. So radiation trapping, which seems to get little attention along with the effects of convection apart from its importance to circulation, is a very significant contributor to the real world of cooling the earth.
Frank, the development of Planck’s Law is fundamental to the ideas embodied in quantum mechanics and an understaning of its implictions is important for a clear appreciation of all quantum electrodynamics which is basically what we are concerned with in applying the Schwartzschild equation to radiation transfer, together with the Einstein analysis of the statistical relationships between black body radiation and molecular excitation densities from which the concept of stimulated eission arose leading to the development of the laser. The many absorption/emission cycles you mention as being necessary to establish equilibrium involve somewhat less than a microsecond to complete – however, unless the density of the radiation field is sufficiently high as in the atmosphere, in general it is not, equilibrium is not achieved and Planck’s Law does NOT apply. Yes, the absorbing medium is too cold of itself to emit visible light, but if the density of the medium is sufficiently low, scattered light and light re-emitted from laser excited molecules are observed. True, some radiation is emitted from a sample of CO2 gas at room temperature, being excited by collisions. However, this is not the radiation we are interested in. What we are talking about is the additional radiation which occurs within the heated sample because of that increase in temperature. At its edges, radiation will be lost and the edges will cool, but the passage of radiation from within the hypothetical sample to those edges is impeded by absorption and re-emission, the bulk of which is in every other direction except that of the out flowing radiation. So radiation trapping is a significant phenomenon in the case of green house gases but does not seem to be properly considered in the IPCC type AOGCMs.
Cheers,
John
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John wrote: “I am not sure what you mean by saying that “hand waving about trapping is dangerous”.”
GHG’s both absorb and emit radiation. Alarmists focus only on absorption or “trapping”, because it is the easiest way to convince simplistic thinking why the earth will be warmer when CO2 doubles. This is what I call hand waving, a non-rigorous rational that creates the impression of understanding.
In reality, GHG’s also emit or cool. Twice as much GHG; twice as much cooling! In a 2XCO2 atmosphere there will be twice as many photons in the CO2 channel traveling a shorter distance – often half as far. In reality, the increased absorption and increased emission nearly cancel. The existence of a GHE depends on the existence of a lapse rate – which can be perturbed by absorption of incoming SWR (as with ozone and the stratosphere). A GHE is likely, but not inevitable and depends on more than just “trapping”.
John wrote: “True, some radiation is emitted from a sample of CO2 gas at room temperature, being excited by collisions. However, this is not the radiation we are interested in.”
This radiation from CO2 (and water vapor) near room temperature interests me because it cools the entire planet. In the laboratory, we work with radiation from filaments heated to several thousand degrees K and visible light from lasers that overwhelm the emission from GHGs near room temperature. We often forget emission exists and how important it is to the planet compared with absorption.
The first step in the derivation of Planck’s Law postulates equilibrium between radiation and the molecules that absorb and emit it. Since we know that such an equilibrium doesn’t exist at many wavelengths in the atmosphere, everything derived using the S-B equation flawed. This flaw is why you hear that “optically thick” layers emit blackbody radiation (emissivity = 1), but optically thin layers emit proportionally to the density of the GHG and the thickness of the layer. The Schwarzschild equation eliminates these problems, but most (including our host) still try to get by with S-B and emissivity.
dI = n*o*B(lambda,T)*ds – n*o*I_0*ds
The dI is lost from the radiation passing through ds and dI is retained within ds and can change its temperature (if convection doesn’t compensate).
[I applied a slight edit.] AZ
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Good points Frank. I get by with SB and emissivity because it is all we need for the modeling ahead — keeping it as simple as possible (4 pipes or emission layers) but not too simple (just a characteristic emission layer).
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Thanks again Frank. I agree with most of what you are saying and that the GHE is not totally dependent on radiation trapping. However, the process of trapping is extremely important and as I showed provides by far the fastest escape route for energy at the earth’s surface to the upper troposphere where it has some chance of being radiated eventually out to space. So, yeah, I think that the effect of trapping by GHGs is the major effect in warming the lower troposphere and also in cooling it.
The derivation of Planck’s law does NOT depend on the presence of any molecules in the cavity, which is assumed to be empty and with “black” walls which emit and radiate at all wavelengths equally readily – a hot, very rough metal surface with free electrons which radiate is the ideal model of the walls.
The introduction of molecules into the cavity came much later, and were introduced by Einstein to show that Planck’s Law and the Boltzmann distribution of energy among the states of a molecule in the radiation field were compatible provided one introduced the concept of stimulated emission, leading eventually to the development of the maser in about 1960 – more than forty years after Einstein’s prediction – and subsequently the HE-Ne Laser in 1963 (I think).
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David Evans October 6, 2015 at 1:42 pm
“Good points Frank. I get by with SB and emissivity because it is all we need for the modeling ahead — keeping it as simple as possible (4 pipes or emission layers) but not too simple (just a characteristic emission layer).”
I agree KISS works! I suggest connections, or provisions for later, between your pipes. Main one is between your cloud tops and the WV pipe. Continuous insolation (somewhere), provides a 2400 J/gm shift with no (required) temperature change. The reverse back to space is also ‘continuous’ nightside.
In this atmosphere, this shift is likely greater power than the combined CO2,surface pipes; even if you include the 80W/m^2 of surface evaporation to your WV pipe.
Do the basic models prohibit such?
All the best! -will-
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John: I assume you realize that the upper troposphere loses more energy by radiative cooling than it gains by absorption. Convection wouldn’t occur without this deficit. Why does everyone focus on absorption/trapping when emission dominates (modestly)? Answer: alarmists want to explain the GHE and enhanced GHE in the simplest terms possible and this distorts our perception of what really happens. Before I was introduced to the Schwarzschild eqn, I spent several years wondering why doubled emission and doubled absorption didn’t cancel or why doubled emission from the “emission layer” wasn’t more important than anything else. Now I can be accurate: When radiation emitted from a warmer location passes through cooler air, increasing the number of GHG molecules in the cooler air increases the amount of heat retained by the cooler air and decreases the heat flux passing through it. Twice as many CO2 molecules emit twice as many photons, but increased absorption decreases net heat flux to space by about 1.5%. For a blackbody, a compensating 1.5% increase in radiation requires a 1.5%/4 increase in temperature or 1 degC at 255 degC.
The derivation of Planck’s Law assumes equilibrium between quantized oscillators and radiation, whether those oscillators are on the surface of a cavity or the gas within the cavity. Blackbody radiation is the product of such an EQUILIBRIUM, not an innate property of matter. As evidence, I’ll offer this passage from the Feynman Lectures online (http://www.feynmanlectures.caltech.edu/I_41.html) with my caps:
“Suppose now that we have a lot of oscillators, and each is a vibrator of frequency ω0. Some of these vibrators will be in the bottom quantum state, some will be in the next one, and so forth. What we would like to know is the average energy of all these oscillators. To find out, let us calculate the total energy of all the oscillators and divide by the number of oscillators. That will be the average energy per oscillator in THERMAL EQUILIBRIUM, and will also be the energy that is in EQUILIBRIUM with the blackbody radiation and that should go in Eq. (41.13) in place of kT.”
IMO, there is no justification for the common practice of using Planck’s Law or the derived S-B equation when such an equilibrium doesn’t exist. When we say that the emissivity of materials is an intrinsic property (not dependent on quantity), but apply different rules to optically thick and thin layers of atmosphere, we are trying to compensate for misusing Planck’s Law.
The S-B equation is modified by an emissivity term for real materials/graybodies. Does this modification compensate for lack of equilibrium? What physics creates emissivity? This isn’t a popular subject for discussion. Absorptivity = emissivity and absorptivity involves scattering or reflection of incoming radiation at an interface between two materials. I’ll speculate that emissivity is due to scattering of outgoing radiation at the interface between two materials – i.e. inward scattering of internal radiation leaving a solid or liquid for air. Another reason that a solid or liquid might have emissivity less than 1 is that their absorption cross-section at certain wavelengths is negligible. In that case, graybodies should be transparent at those wavelengths. This explanation is obviously wrong for solid materials, but partially correct for gases.
You are, of course, correct that emission can be either spontaneous or stimulated by nearby photons (or the radiation field). The emission term of the Schwarzschild equation does not include stimulated emission; it is only correct for an atmosphere in LTE and must be modified when scattering is important. The following paper from an obscure author in an obscure journal derives everything about atmospheric radiation starting from Einstein coefficients and ending with his value for the radiative forcing for 2XCO2. He discusses stimulated emission in our atmosphere in Section 2.3.2. It is 3-4% of spontaneous emission for the strongest CO2 line. Unfortunately, much of this material is very difficult reading for me.
http://www.hindawi.com/journals/ijas/2013/503727/abs/
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David,
This is a very interesting presentation and discussion. We await further sections/chapters with anticipation. If I could make a very simple comment on your diagram showing the analogy between a set of parallel resistors and the additional energy “piped” through water vapour to outer spaced, I believe there could/should be a series resistor in the input circuit on the LHS. In the case of an increase in Rc, that would lead to an increase in the voltage applied to the other three resistors which itself is analogous to the fact that an increase in carbon dioxide further warms the sample of air + water vapour + CO2, from which the increased radiation by water vapour occurs. Just a thought. Best wishes, John Nicol
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A further comment David is that the presence of additional CO2 in any sample of air at any height will cause more warming in that sample, irrespective of height. This increase will be off set, as you remark, by increased flow through the H2O pipe. The increase in the H20 Pipe will arise because the slightly higher temperature will lead invariably to a higher proportion of water vapour molecules being in the upper states from which additional radiation will thus occur, off setting the effect of the CO2.
The effect of doubling CO2 in a totally (unreal!) stable atmosphere, would be to effectively half the height of the (somewhat exponentially formed) distribution of energy and therefore of the temperature “increase”, thus lowering the point at which the increased effect of H20 becomes important. Again in our unrealistic troposphere, this feedback will only persist while the height remains above that at which water vapour acts also as saturated green house gas. However, because of the increased convection caused by the additional temperature of lower samples of air, the heat is rapidly transported to these higher levels and the feedback would be expected to persist as before to first order at least.
With regard to its not being a ground “surface” feedback, this is only partially true since the general circulation process would otherwise bring warmer air back to earth in the mid-latitudes, were it not ofr the benefits of your newly advised feedback through the H2o Pipe.
John Nicol
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John,
If the rerouting feedback was a response to surface warming, then it would also occur for increased ASR and all other climate drivers, which is absurd. Therefore it’s not a response to surface warming.
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What mega-intelligent climate scientist?
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The ones that do NOT believe in AGW. Most of whom are either Dead, Retired (and will talk about it) or are silent on the subject for fear of their livelyhoods.
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‘The loss adjusters’.
Intelligence at work.
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Well only 97% of them!! Just ask them! I much prefer the 3% that know, that they do not know! 😉
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David,
I have a question which indicates how little I really do know when it comes to Science, but no one has ever really explained it for me in a manner I can, umm, see.
If water Vapour is H2O, and floats gently in the air around us, and there is even a pretty large build up in the form of clouds, especially those huge Cumulo-Nimbus monsters.
So, here we have CO2, which in fact is virtually three times heavier than the suspended water vapour, H2O, and that CO2 is virtually heavier than all the surrounding air.
If it’s being emitted, say in a huge concentration, directly above a large scale coal fired power plant, why would it not, being heavier than air, settle back towards the surface rather than rise, and rise, and rise?
I know it’s your typical ‘newbie’ question, but it’s always puzzled me, and I’m sorry to show up my lack of basic Science knowledge in this fashion.
Tony.
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The pull of gravity is small compared with other forces acting on the molecule
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Human induced CO2 falls pretty much within the vicinity of the power station.
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And I know it looks like I’m not keeping to the main topic, but when I work out that for a plant like Bayswater with all four units in operation, that’s almost 50 Tonnes of CO2 being emitted every minute.
I then wonder about Lake Nyos.
Tony.
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Great question Tony.
You would think (or it seems) that it would be easy to measure?
Sample the air at say 10 different heights from ground to space above a power station? See if there is variation?
Too easy?
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Tony , i remember from years back reading that CO2 descending through the atmosphere back to earth is like standing at the top of a steep hill with a rugby ball and rolling the ball down a slope thats covered with rocks, because of gravity the ball will eventually reach the bottom of the hill but will be delayed by collisions with the rocks on its way down.
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Hi Tony
Came across the Lake Nyos thing some years ago and it was likened to the biblical event of deaths of newborns. Story was that older males were housed on top floors of houses and newborns at ground level. Sounds logical.
An event like Lake Nyos would have sent a wave of CO2 through the location and smothered those on ground floor.
This is just a possible; not sure how accurate.
At lake nyos had a look on Google Earth and the lake is surrounded by a barrier which seems to be at least 20 metres above lake level.
The CO2 was released from the lake bottom where it was trapped in a layer which had remained sealed for too long.
The gas would have bubbled up, still relatively cool and flooded the valley created by the surrounding hills.
Lots of wind or sunlight might have saved them but I think it was in the cool of the night.
KK
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Tony
I don’t know if you were ever stationed at Williamtown Base, but if you were you would know that the Hunter Valley is a windy place. We are subject to strong katabatic/anabatic winds up and down the valley past the Bayswater and Liddell power station complex, so there must be a hell of a lot of mixing of the air column around them.
They monitor for air quality at a couple of sites but I think it is only for particulate matter from the adjacent mines. The greenies in Newcastle are always whinging about coal dust.
I don’t think we are in any danger of a Nyos repeat, although there are hollows around both stations where CO2 could pond under cold, still conditions. Presumably the CO2 is quite hot when it emerges from the stack so I imagine it ends up very high in the air column where it is dissipated rather quickly. I used to work right next to Liddell without any ill-effects. I now live about 50km south of the stations and the plants in my backyard are loving that CO2.
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Hi Beowulf
I live in Newcastle and what is a Katabaic or anabatic wind.
I must have known some time in the past.
Are they related to the diurnal bulge that pulls air to the east early and sends it west in the afternoon.
KK
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KK
Living in Newy, you are certainly familiar with those winds. The Hunter Valley has a near perfect topographic setup to promote their development. They are caused by differential heating, in this case between land and sea, which in turn causes localised pressure gradients.
Your anabatic winds are the nice afternoon sea breezes on a hot, otherwise calm day. As the land heats up, the hot air above it is displaced by cool, dense, ocean air rushing in. Effectively the hot inland area of the valley sucks in cool ocean air.
Katabatic winds are the opposite, caused by cold air drainage from the cooler inland areas in winter. Cold air from high points like Merriwa and Murrurundi and Barrington at the very top of the valley is joined by air from a zillion other point sources lower down, causing it to gain speed and volume as it flows its way to the sea at Nobbys. Those are (some of) your cold north westerlies.
The effects of anabatic/katabatic influences can be easily overridden by stronger weather systems like southerly busters etc.
Gullible Gavin on NBN occasionally gives an explanation of these winds when he isn’t busy scaring the kids with fairy tales of global warming temperature “records”.
Hope this was of help.
BW
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Thanks Beowulf
The southerly buster.
Have seen it marching up the coast on many occasions.
KK
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Beowulf,
I was at ‘Billsville’ (Williamtown) for 11 years, (5OTU Sabres and Macchi’s, 481MSqn, 76 and 77Sqn Mirages) 1970 until 1981, and it was probably the base and postings I loved best during my 25 year tenure in the RAAF.
I distinctly remember those cold August winds.
Great times, when Bayswater was nowhere near ‘front of mind’ as it is now.
Tony.
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@el gordo: Yeah, within the vicinity of the power stations, under the long exhaust fumes, the snow is hot in winter by radiation from CO2.
Mind to show a photo of your hot snow? /sarc
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Its heavier, doesn’t mix well and is not evenly distributed, so it falls relatively quickly.
Back radiation is a hoax and CO2 isn’t a sky blanket.
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What magic forcing are they?
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“What magic forcing are they?”
There are none. The theory of gas has all molecules with the same space volume. Certainly in a ‘mixture’ some molecules have a higher collisional cross sectional area and perhaps slower speed. Consider a 50/50 mixture of He/SF6, The wee-speedy/big-oaf. Do they really create the same volume with different densities? How do you know? 😉
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Tony, Dr. Evans is describing generically both the Lindzen adaptive infrared iris and the Eschenbach cumulonimbus albedo feedbacks. Water vapor and albedo. Both, phsycally. Undifferentiated mathematically. Key point is mathematicallly generic.
For more on how AR4 completely fudged this using selection bias, read the penultimate climate chapter of ebook The Arts of Truth. Cheap. kindle or iBooks or whatever.
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Lindzen’s adaptive infrared iris feedback and Eschenbach’s cumulonimbus albedo feedback are in response to surface warming rather than increased CO2, AFAIK, but I’m not certain.
Does anybody know for sure?
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The most insightful source for this question is Judith Curry’s post on May 26, 2015. She links to materials obtained directly from Lindzen. As I understand it, the effect is of course indirectly related to surface warming, since it involves convection. It is directly caused by convective cell aggregation ( they get much bigger and fewer) which Mauritsen, Stevens say is purely a consequence of physical air mass rearrangements in the troposphere. Descending cool dry air outside the convective cell supresses convection there, concentrating it elsewhere, which Judy thought correct. The result is fewer but larger thunderstorms with more rainout, so less water detrainment from the anvil, so less cirrus. I would add also less residual water vapor in the upper troposphere where it matters most.
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Dr Evans
A quick check reveals that both these behaviors are responses to surface temperature as stated.
from Lindzen
it has been found that the area of cirrus cloud coverage normalized by a measure of the area of cumulus coverage decreases about 22% per degree Celsius increase in the surface temperature…
This new mechanism would, in effect, constitute an adaptive infrared iris that opens and closes in order to control the Outgoing Longwave Radiation in response to changes in surface temperature
from Eschenbach
Like cumulus clouds, thunderstorms also form in response to increasing temperature…
…When tropical temperatures are cool, tropical skies clear and the earth rapidly warms. But when the tropics heat up, cumulus and cumulonimbus put a limit on the warming
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Thank you Rud and ScotsmaninUtah.
Ok, they both follow the conventional paradigm, suggesting ways the total feedback to surface warming (f in Fig 2 of post 3) might be more negative.
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Carbon dioxide released from a bottle will fall but eventual mix with the surrounding air. All air molecules are falling but being bumped up soon after by colliding with another molecule. The percentage of air that is CO2 changes with altitude because it is heavier but the concentration per unit volume is decreasing anyway because the air is thinning out making the former irrelevant.
Reminds me of the stupidity of expecting the atmosphere to be isothermic (no temperature change with altitude) without air currents.
60
The CO2,O2,N2 gases are in practical terms virtually the same density(especially wrt the mass to surface area ratio).only in still air such as in a mine or enclosed area is there a danger of the CO2 settling and causing an asphyxiation hazard.
40
Tony
It’s been a while since commenting here but the issue that jumps out for me its that homogeneity eludes everyone! It really doesn’t matter which “pipe” is smoking, the atmosphere is generally an homogenous mix of the components, be they CO2, clouds, oxygen, etc etc. Even as they are produced, the mixing is taking place. The only exceptions to the rule apply in tunnels and caves where the different gasses are not influenced by wind or the effect of the earth’s rotation which mixes everything.
Could it be that we are all wrong to tackle this from a micro or a macro perspective when both are entirely irrelevant in the overall scheme of things?
Years ago when the greenhouse effect was first tabled, my thoughts focussed on the difference between absorption, reflection and refraction with respect to a real greenhouse, you see I’m in horticulture and have years of greenhouse growing experience. A real green house is like a tunnel where the sun’s rays penetrate. Depending the angle of the sun to the greenhouse roof, refraction has a greater or lesser influence on temperatures at the bench. Worst case scenario is where greenhouse have been placed east west instead of north south. With east west greenhouses, the temperatures on the south side of the greenhouse can be significantly lower. I tumbled to this while managing an operation where the greenhouses all ran east west (not my design) We were growing Tea tree (Melaleuca alternifolia) in millions at the time for the emerging Tea tree plantations. We had problems with germination on the south side of the greenhouses so I set up temperature probes across the houses from north to south. Bear in mind these were heated houses with hot water in capillary pipes in the sand under the benches. No surprise to me, the bench temps on the south side were up to 6 degrees C cooler in the mornings than the north side of the greenhouse.
What may you ask has this to do with the planet? For mine it’s obvious, it’s the shape of the curved greenhouse roof and the shape of the earths atmosphere are the same. Depending the angle of the sun’s rays, they are absorbed, reflected or refracted to a greater or lesser degree. The only difference is that the greenhouses I worked with had inflated roofs and were sealed to keep in the heat!
OK then you might ask how does that influence the planet? For mine, the wind and the rotation of the planet are not the only mixing influence on all the component gasses in the atmosphere. The heat differentials across a given slice of atmosphere will work tirelessly while ever the sun shines to mix the components of our atmosphere regardless of wind or other influences.
I very much doubt that any so called experts have considered this.
130
Tony, it does – on average. But being a gas it is constantly being bombarded qnd knocked about by N2 and O2 and so it, as well as the O2 and N2 are able to gain a certain amount of gravitational potential energy m x g x h which is converted from kinetic energy 1/2 m v ^2 so it won’t settle out completely.
Hot expanded gasses are also lighter than cold compressed ones so the expanded hot gas volume rises relative to the cold, a result of the conversion of kinetic to potential energy. There isn’t just a free space to fall back to earth so the CO2 bump around, up and down as they float around.
10
The gases from a smokestack are warm thus less dense and therefore buoyant. The drag of the air current exceeds the tiny winy difference in the mass or density of CO2 verses the other gases. The CO2 molecule like pollen and dust in the air are gliders. In addition H20 in the effuent of the stack makes the air more humid and even lighter or less dense that is part lift that creates the upwelling current that lifts all molecules in the stream.
00
Ha! Nice one Tony.
Many peasants , like me , believe that one of the the reasons that grass grows faster in a paddock sheltered by trees , is that the heavy CO2 emitted during the night by plants selfishly compromising our grandchildrens’ futures, is , not having been blown away by the wind , available for enhanced photosynthesis during the day.
🙂
80
CO2 from rotting hydrocarbons, so much loved by growing grass and trees. Rather than that emitted from Mona Loa, now politically blamed on coal mining. Oh save us from the scourge of the not very elite!! 😉
54
The reduced wind velocity due to the trees will reduce soil water loss to the atmosphere, as will any shading. There is also evidence that trees can translocate water from deep in the soil profile to the shallower tree roots. Air movement would have to be very still for night-time transpired CO2 to still be about when the sun boots up photo synthesis…..I guess it could happen in some very sheltered spots or foggy areas.
10
Tony, I have often wondered about a similar thing myself. In the past I sometimes mused about how the CO2 ‘gets to’ the surface of the leaves of a tree for photosynthesis. My muse was based on the idea that, when the leaf had absorbed all the CO2 molecules immediately in contact with it, how did it then find new CO2 molecules to photosynthesize?
I came to the conclusion that it is the wind and the general turbulence of the atmosphere that ‘brings’ the fresh CO2 molecules to the surface of the leaf. If you carefully watch a tree, even on a very hot and still day, you will see that there is just the slightest movement of air in the tree and this is constantly refreshing the availability of CO2 molecules to the leaves for photosynthesis. When the wind is actively blowing, this CO2 refreshment process is abundant.
So the factor in the small question I was asking myself is that the atmosphere is not still.
The same factor may be the solution to the question that you raise. The atmosphere is constantly in a situation of dramatic turbulence (the weather and seasons etc) and this is the reason why the components of the atmosphere (such as CO2) do not separate out according to their atomic weights. What I am saying is not the peer reviewed result of a major scientific study – it is my personal conjecture – but it makes sense to me.
So, in your thinking about this it may be helpful to remember that the atmosphere is not still. It is turbulent.
10
I’m no expert, but I remember from high school that leaves were in fact hollow. Air is accepted into the leave through the Stomata and circulated internaly. The stomata can open and close depending on temperature and light conditions. I tried to find a good diagram in Google but came up a blank.
00
Yes Greg, I understand that. But the question is NOT how the CO2 gets INTO the leaves – I know about the Stomata – but HOW the CO2 is brought to a position where it it immediately adjacent to a stomata or ‘pore’.
If the atmosphere were completely still, the stomata would take in the molecules of CO2 immediately next to them … and then what?? Having taken in the immediately available molecules of CO2, there would be no further molecules available UNLESS the air itself was moving – ie, turbulent. I’m talking about the very small molecular level.
It’s only a minuscule point I am raising but it goes to the issue TonyfromOz raised way back at point #2. The atmosphere is turbulent and therefore the components do not separate out according to their atomic weights.
10
if it was as still as you imply the molecules would not move into the stomata but of course at the micro level, unless actually frozen, they are moving about crazily fast all over the place. Also tiny eddies would be happening unless all surfaces and anything else were somehow completely identical in all physical properties even at the atomic level.
00
if it was as still as you imply the molecules would not move into the stomata but of course at the micro level, unless actually frozen, they are moving about crazily fast all over the place. Also tiny eddies would be happening unless all surfaces and anything else were somehow completely identical in all physical properties even at the atomic level.
00
Tony,
How about “Nobody knows how Earth’s atmosphere actually works!” 😉
44
Turbulence (wind/convection) mixes the gasses quite well, In the absence of wind CO2 will concentrate to the bottom of the air column, as is experienced in limestone caves where “bad air” settles to the bottom of still caves. If you look at the AIRS maps you see the CO2 is reduced in cold areas and in high precipitation areas, due to the ability of CO2 to dissolve in water droplets with a massive surface to air ratio relative to the ocean-air surface.
10
David,
If CO2 makes it difficult for heat to radiate out into space then would increased CO2 make it more difficult for heat to radiate in from space?
51
Heat coming in is more UV-visible. Heat going out is infra red.
Co2 is transparent to UV-visible.
But if the Martians send an orbiting giant bar-radiator, all bets are off.
110
CO2 has (almost) no effect on incoming radiation, because it doesn’t absorb (much) at the wavelengths of the incoming radiation.
100
According to Wikipedia:
Given the level of IR in sunlight can you please elaborate on its lack of effect on CO2?
51
Rollo,
This graph of incoming and outgoing spectra shows the relatively small interaction of CO2 and incoming radiation.
Googling also found this article on Watts by Ira Glickstein.
40
What search term reference? 99% insolation below 2.5 microns.
03
Dr. Evans, will there be a test on this series? If so, will it be essay or multiple choice?
80
I absolutely love the parallel resistor analogy. Should be an “aha” moment for nearly any observer.
Thank you
70
It was for me.
I’ve never thought of it in that manner before now. It places that whole ‘pipe’ thing into perspective.
Tony.
50
I got there differently, since not an EE, on the parallel pipes post. But still got there. As a former econometrician, I feel this strange convergence to Dr. Evans stuff I used to know. But forgot but am now remembering. Is he awakening some collective Godzilla?
80
Awakening Godzilla would account for one deep ocean hot spot I guess……
60
Missing Heat! Sounds like the Kraken
Alfred Lord Tennyson
20
Oh jeeze, still with the “pipes” analogy, well I suppose if that’s all you know you have to run with it.
The electrical resistor analogy does not work with light energy, sorry. It may be convenient but it is wrong. The only way to get the correct answer is to follow every photon though the system. It is a pain but that is the only way to get a proper result.
The electrical circuit analogy using only resistors does not work, there are also capacitors in the system and you need to consider the frequencies of the incoming energy (with a period of 24 hours, duty cycle varies with distance from the equator). It is an AC circuit and the IR energy emitted by the surface “short circuits” the resistors via the equivalent of capacitors and after a very short delay exits to space.
The atmosphere of the Earth is not a DC circuit, you cannot analyze it correctly by substituting resistors.
Oh, by the way “outer space” is not “very cold”, it is instead devoid of any substantial amounts of matter. Since temperature is a measurement of the vibrational rate of matter, any volume without matter does not have a temperature.
The off quoted “background temperature” of ~ 3K is the theoretical blackbody temperature that best matches the spectral shape of the background radiation, not an actual temperature. If the temperature of “space” was ~ 3K the Apollo Astronauts would have frozen to death when they were a mere half inch away and only separated by a thin skin of aluminum. They were separated from a vacuum with no thermal capacity to “remove” heat from their spacecraft via conduction or convection.
The Apollo 13 Astronauts where able to survive with only their own body heat for several days before re-entering the Earth’s atmosphere. If it was 3K outside the vehicle they would be dead.
Cheers, KevinK.
78
I know that the absorption of light depends on the frequency but what the hell could come close to being like a circuit with a capacitor in it? If feedbacks oscillate, they are stronger??
Like the Earth, it warmed up in sunlight and cooled down in the darkness, down to 4°C at one stage.
10
I should add that even at ground level, conduction of heat from a surface to air is poor (hence pockets of air in insulation). And air temperatures are very important in this day and age.
Interesting question for climate scientists. Does an object in pure N2 cool as fast as an object in air with GHG but blowing across it so it doesn’t warm up?
20
The way out for heat might be like a DC circuit. It is not AC, otherwise the heat would go up and down.
10
How much for a large bag of your photons?
How much for even one of such fantasy, to become known as part of this physical?
01
Will, you’ve put up a number of posts dismissive of the photon concept
Like most science graduates, I did the photon experiment in Physics 201 where one could “hear” individual phtons colliding with the plate. Similarly with the various wave observations, one could predict the result of interference etc
Since then, a mere half-century I think, I’ve taken the occasional opportunity to try and uderstand how practising physicists deal with the contradiction (to me) of the particles vs waves nature of light. Most I’ve read or asked simply say: “I dunno, it’s just so”
How do you deal with it, please ?
10
“Like most science graduates, I did the photon experiment in Physics 201 where one could “hear” individual phtons colliding with the plate.”
Would you please explain how one may hear EMR flux in a vacuum? I have witnessed a 7 picoseconds 40 Joule emission from a CO2 laser destroying a 8mm thick polished Ge witness sample whose transmissivity reduced to zero from the EM field strength in the 7 picoseconds transit time! IS this your “PHOTON”? Just what was your claimed ‘individual phton’ experiment?
The Photon as a gauge boson mediating the partitioning between transmission, reflection, and absorption in whole units of Planck action is fine. The concentration of EMR flux into fourspace action density so that an action of specified minimum work function (emission of an electron from nickel) is also fine. The concept of each cycle of EMR flux having a particular energy in ev, is misleading, but sometimes useful as a concept!
There is this idea that ‘photons’ are thermal EMR bullets shooting off in every direction proportional to T^4 of anything without regard to the fact that such is not heat in any form, must conform to all of Maxwell’s equations, including the resolution of all Poynting vectors at every point in space!! This is the accepted photon concept in this CAGW scam! Such is beyond my acceptance of ultimate stupidity of any earthling! I hope this helps!
00
And you apparently are not an EE.
I’m sorry, did I miss the part where the resistors were claimed to be everything? Or were you not awake during the synopsis?
50
” It is an AC circuit and the IR energy emitted by the surface “short circuits” the resistors via the equivalent of capacitors”
No… it doesn’t “short circuit” the resistors. It places a frequency dependent reactance in parallel with the resistance. This can create a significant change or one of little to no significance depending upon the value of the capacitance between earth and the parameters of the relevant pipe.
50
“CERES – imaging data “
Examining the CERES data for the last decade there are a few things which appear interesting
For OLR in the period 2009 from January to December ,
there is a pattern where:-
above 45 degrees North latitude the OLR value never exceeds 275 W/m2
below 45 degrees South latitude the OLR value never exceeds 225 W/m2
In addition there is horizontal asymmetrical jitter or oscillation (5 -7 degrees) about the Equatorial latitude where the highest OLR is seen
OLR maximums never move West to East (or appear not to , most high value OLR positions remain fixed).
20
If you look at the data vs longitude expressed as time of day, do you notice a pattern east and west of local noon?
00
A couple of papers by Richard Lindzen may be of interest in relation to the discussion.
Some coolness concerning global warming
RS Lindzen – Bulletin of the American Meteorological Society, 1990
http://eaps.mit.edu/faculty/lindzen/cooglobwrm.pdf
On the determination of climate feedbacks from ERBE data
Authors. Richard S. Lindzen, Yong-Sang Choi, 2009
http://onlinelibrary.wiley.com/doi/10.1029/2009GL039628/full
In the second paper the authors refer to a third paper that extends their discussion to the extra-tropics.
There was also a paper that brought several rebuttals and counterarguments from Lindzen and his co-authors.
Does the earth have an adaptive infrared iris?
I think it would be prudent to review these papers and comments while developing the concept of rerouting feedback.
20
I am far from convinced that even more and more complicated mathematical formulae can ever hope to realistically model the chaotic, non-linear, dynamic system which is the nature of the of the sun earth relationship. At any given moment there is an approximate difference of about 100 degrees between the hottest and coldest places on earth. Of what possible use is it to assume an average temperature of say 15 degrees centigrade as the starting point? Even if the model formulae are realistic, if you can’t define the boundary conditions, manipulation of the formulae is pointless IMHO
130
They can’t, David Evans is more right than the climate modellers but he is still wrong if for no other reason that the model still relies on many assumptions including the A=R assumption that we’ve already shown is wrong, that is the four pipes model omits the 157 other pipes in the climate. And it sticks to the assumption that the temperature of the CO2 is somehow going to change the ability of CO2 to intercept and reradiate EMR photons.
However that doesn’t necessarily mean that his contribution is useless. I’m still finding it fascinating and thought provoking.
50
Models are always wrong. They simplify a situation, omitting lots of stuff. A good model captures the essence of a situation by getting the main behavior correct most of the time, presumably by accurately portraying the 5% of the reality that governs 95% of its behavior, or something like that.
The current conventional climate models have been found wanting, badly. I claim they have the wrong architecture, so they have not got a ghost of a chance of working properly. They seemed to work for temperature (though not the hotspot) when the world was warming in the 1980s and 1990s, but have failed since then. A model that has the wrong architecture would act like this — correct sometimes by accident (especially if tuned to fit the data), but failing a lot of the time too, and no amount of hammering on the model can make it work all the time. It’s just wrong.
By changing the architecture we can make them perform better. Not perfect, just better, at least with respect to CO2.
100
I think thats what I said.
02
Warning novice question ahead, if CO2 is heavier than air hoe does it vent into outer space or cross the Karman line?, also as CO2 can be absorbed and carried by H2O it must separate at some point in the atmosphere, H2O never vents to outer space AFAIK as it’s a closed loop Earth system.
10
Why do you claim that CO2 vents to space?
13
He didn’t, he asked if it does.
31
hoe means if or how???
22
Sorry Will hoe=how (cheap keyboard), I confused ‘energy’ escaping earth to space via the CO2 pipe with CO2 itself, as for CO2 and H2O interacting does Henry’s law cover this or has CO2 been overlooked as having a more inert quality to others?
10
From one of the few left with any personal integrity, HOW THE HELL WOULD I KNOW?
32
Henry’s law is deliberately ignored by mainstream climate scientist. 98% of CO2 in the system is dissolved in the oceans with the ocean atmosphere exchange estimated at about 10% per year. For those who are not aware of henry’s law, it states that to double the concentration of CO2 in the atmosphere you have to double the amount of CO2 in the entire system, which at 2% of 2% will take a few thousand years. Then there is the disgraceful use of the uncalibrated CO2 ice core proxy that is temporally modified to make it fit, while three other CO2 proxies show the CO2 level was significantly higher in the recent few hundred years than the BS Ice core proxy.
60
yonniestone, your question is a good one,
Extract from ‘Tomorrow’s Weather’ Alex S. Gaddes (1990) pp55
“Obviously if the rising carbon dioxide level in the atmosphere were the only consideration one could predict, unequivocally, that inundation of the lowlands of the Earth would be inevitable in the immediate future.
However, (see Ref. Nos. 12 and 13) it [rising carbon dioxide level] could well turn out to be lucky for us, in the light of those other factors which act in the opposite way to carbon dioxide in the atmosphere. I refer to wind-blown and volcanic dust in the atmosphere and the ever-intensifying albedo factor.
May be glad of Greenhouse Effect
Who can say that sometime in the not-too-distant future, we will not be glad of the “extra blanket” provided by an enhanced “Greenhouse Effect?”
Apart from the anti-Greenhouse Effect factors mentioned above, there is another powerfully active component at work, which governs the amount of CO2 in the atmosphere.
According to Rankama and Sahama (Ref. No. 14) the oceans act as a sink for any build-up in carbon dioxide above a partial pressure (PP) in the atmosphere; that once the critical PP in the atmosphere is reached, the excess carbon dioxide is taken into solution by the oceans.
They note that the cold polar waters are capable of the greatest absorption of carbon dioxide. Apparently the equilibrium ratio of carbon dioxide in sea water to that in the atmosphere is 50:1…..”
David Evans appears to be ignorant of the Oceans’capability to act as a CO2 ‘sink’ – and the importance of the ‘Albedo Factor’ in countering CO2 increase.
While there are Electromagnetic factors involved with interactions between the Sun and the Earth – I am mystified by Evans ‘Electrical Circuit’ and ‘Four Pipe’ analogies.The overwhelming driver of Climate is ‘Convection.’
An updated version of ‘Tomorrow’s Weather’ (including ‘Dry Cycle’ forecasts to 2055,) is available as a free pdf from [email protected]
35
If we think of the Southern Ocean as a large sink and the Humbolt Current a conduit to the warmer waters of the Pacific, where more CO2 is liberated, then Mauna Loa is sitting pretty.
In your estimation is the rise in carbon dioxide (recorded at that location) natural or human induced?
10
Don Gaddes, I am ignorant of neither the Oceans’ capability to act as a CO2 ‘sink’ nor the importance of the ‘Albedo Factor’ in countering CO2 increase.
Indeed, a sizable portion of the remainder of this series of blog posts is on albedo.
However Don, appearances can be deceiving. It appears that the blog posts to date in the series are on different topics and cannot mention everything all at once (length…). Tricky, isn’t it?
Still mystified by a simple analogy? Maybe read the two paragraphs above Figure 1, carefully. No mention of your mysterious “Electromagnetic factors” — I think you made them up.
40
David,
Glad to hear you are cognisant of the CO2 ‘sink’ capacity of the Oceans. I would have thought you might have mentioned it in this post, which seems to be about fluctuations in CO2.
Are you implying that there are no Electromagnetic Factors participating in the relationship between the Sun and the Earth?
I await your impending discussion on the ‘X Factor’.
00
With regards to the water-vapour pipe.
With super saturated air, having liquid water in micro droplets instead of being a gas is not a lower energy state, as it would be if the droplets were large (as a large portion of the water molecules make up the surface). Small droplets are nucleated by oxides (SO2, NOx), small particles and ions because it having these dissolved in water lowers the energy of the system.
I brought that up because it means that the new droplets would be higher in temperature than the surrounding air and cooling by emitting IR that is broad like the emission spectrum of liquid water rather than vapour. So its not only the thinness of the air at altitude but also emission at frequencies not absorbed by water vapour that leads to a larger contribution to OLR than if it were simply air containing water vapour cooling down.
60
Interesting point, RB.
20
Perhaps a close coupled CO2-H2O pipe? I can picture that happening but then when I think of the relative percentages of CO2 to water the thought; “why are we even worrying about this”,does cross my mind. Certainly rain contains dissolved CO2 but I’m unsure what happens in the vapour “phase”.
10
Perhaps a close coupled CO2-H2O pipe? I can picture that happening but then when I think of the relative percentages of CO2 to water the thought; “why are we even worrying about this”,does cross my mind. Certainly rain contains dissolved CO2 but I’m unsure what happens in the vapour “phase”.
00
Nice presentation David. Thank you.
20
“…when increasing CO2 makes it more difficult for heat to radiate to space on the wavelengths at which carbon dioxide absorbs and emits, some of the blocked heat simply reroutes out to space on the water vapor wavelengths instead”
‘Re-routing’ seems to be an example of non-linearity within the climate system, something not well understood or recognized within current climate models.
20
“someone stole my photon”
an intriguing idea, I especially like the idea of the CO2 giving up it’s energy immediately to the more abundant water vapor.
( ~0.33% by weight; compared to CO2 ~0.04% )
considering H2O has a very small moment of inertia on rotation which gives it a rich vibrational-rotational spectra (vapor phase) it contains tens of thousands to millions of absorption lines and thus it lends itself very well to this idea of re-routing feedback.
One of the mechanisms may use Kasha’s rule – where emission wavelength is independent of the excitation wavelength.
CO2 –> emits hf1 photon –> h2O absorbs it
H2O goes through vibrational relaxation
H2O —> emits photon hf2
or something approaching this 😮
Although this applies more to florescence , there have been experiments where Infrared laser-induced fluorescence (LIF) of water vapor have been conducted.
If this is occurring then CERES should detect it as CERES measures radiances in three broadband channels: a shortwave channel (0.3 — 5 µm), a total channel (0.3 — 200 µm), and an infrared window channel (8 — 12 µm).
unfortunately I do not know enough about this area
40
An interesting comment.
Completely Off Topic, water is an amazing substance and can exist in several structural forms.
Water makes up a large proportion of horn in our bodies.
This is the fingernail and toenail material; mostly water.
KK
10
Having worked for many years in heat transfer, it has always been obvious to me that the so-called ‘greenhouse effec’t and the Trenberth ‘Earth’s Energy Budget’ diagram are a load of humbug. The cooling of the Earth is a ‘simple’ heat transfer problem, with several paths available for heat transfer, as David has shown. If the heat transfer via one path (or mechanism) is changed, then the system rearranges itself with the heat through all the paths changing, the overall effect on the Earth’s temperature being minimal. Of course it has to be recognised that the problem is not ‘simple’, being a 3-dimensional one, with many time-dependent variables.
210
Convective cooling (which removes more energy from the surface than radiation) is observed to increase exponentially with temp but is apparently modelled to only increase in a linear fashion. Deliberately miscalculating the largest negative feedback in the system…..
20
Philip,
This is a hoary old complaint. Surely we have all moved on from Trenberth bashing. The famous Trenberth diagram has estimates for energy flows for conduction/convection, latent heat transfer, and radiation. It certainly may not be a perfect model but it is fascinating how people who deprecate it never come up with an alternative set of statistics… preferring just to dismiss it as a load of rubbish!
One thing Trenberth et. al. did that has indeed caused considerable misunderstanding over the years is their use of radiative potentials for the radiation flows between surface and atmosphere in both directions, whereas all the other energy transfers in their diagram represent actual energy flows. If this makes you uncomfortable, just subtract the two values (396Wm-2 up and 333Wm-2 down) to give you a net real energy flow of 63Wm-2 upwards, in full conformity with the Second Law of thermodynamics. This will help you to avoid trotting out the old and discredited argument that Trenberth advocated ‘back radiation’ in violation of the 2LT.
00
David,
I was not aware that the so-called back radiation of 333 W/m^2 was regarded by Trenberth as a “potential” field. Having defined it in the diagram, it has to be a “real” field, capable of warming the surface of the earth, while the 396 W/m^2 is the total radiation from a heated earth. At the surface of the earth, a body is thus regarded as being in a radiation field of density rho = 333/c where c is the velocity of light. The body is thus heated to an equivalent equilibrium (radiative) temperature because of this back radiation. The error in Trenberth et al.’s work was to ignore the enhanced absorption of the downwards radiation by the increased CO2 at the lower levels which is always more dense than in the layers above.
John Nicol
00
John,
Thanks for your response.
It is not so much what Trenberth believes as what radiation physics says! It is a fact that, if two radiation fields face one another, this results in a net flow of energy between them that is equal to the difference in their values. (Thus for example, if two equally hot surfaces face one another, NO energy is transferred by radiation between them.)
The other numbers at the earth-atmosphere boundary in the Trenberth diagram are not to do with radiation and therefore represent real unidirectional energy transfers.
It is certainly possible to criticise Trenberth for not making the distinction clear but the numbers in the diagram only balance (as they must) if the radiation figures to and from the surface are interpreted as I have said.
On your other point of criticism of the diagram, concerning the effect of “enhanced absorption of the downwards radiation by the increased CO2 at the lower levels”, which numbers in the diagram do you propose should be modified and to what new values? Unless you can answer this, your criticism seems to me inappropriate.
Regards, David C
00
Thanks David. On my last point first, my comment on absorption was not a criticism of the diagram per se but regarding the effect of increasing CO2. The radiation increase suggested to arise from increased CO2 by Hansen et al., from which the diagram is taken, omits to take account of this absorption effect which strongly modifies the downwards radiation so that the intensity of this radiation downwards at the ground does not increase with increasing CO2, even though the air above does increase in temperature. This is easily shown analytically for a constant density field of air and CO2, by integrating the radiation from each level proceeding to the ground. None of the numbers in the diagram of course could reflect this fact since the diagram is presented for a given CO2 concentration which was 380 ppmv I think – but not sure – NOT for a varying concentration which the diagram itself does not address.
I am not sure if we are on the same wavelength (pardon the pun) in regard to the exchange of energy between two bodies which are at the same temperature, but your comment that “NO energy is transferred between two bodies which are at the same temperature” is not correct. Energy is transferred from Body A to body B and energy is transferred from B to A, but these amounts of energy are the same so there is no NET transfer of energy. Any body in the region between the bodies will absorb radiation from both sources. However, I may have interpreted your comment incorrectly since I notice you refer to net energy in the preceding sentence. If I have misunderstood what you are saying then I apologise. Regards, John
10
John,
OK thanks for clarifying the issue over your last point. The Trenberth diagram is an attempt at providing an energy balance at a particular point in time and so it is not in itself a suitable model for showing how the balance will change with increased CO2.
Re. your first point, you raise a very interesting issue when you suggest that radiative energy is transferred in both directions between two facing bodies that are at the same temperature but that, because the flows are equal and opposite, there is no net energy transfer. This is indeed the position adopted by most physicists who adhere to the particulate theory of two-way photon streams.
The alternative view, that of traditional thermodynamic field theorists, is that the potentials offset one another and so no energy flows in either direction.
I would suggest that both views are equally acceptable since they result in the same conclusion: no net energy flows from either body to the other. The danger occurs when the traditionalists accuse the particulate adherents of having a theory that violates the 2LT – which it clearly does not – because (in the case of non-identical temperatures) the net flow is always from hotter to cooler surface in full conformance with the 2LT.
00
The greenhouse gas concept is a much misunderstood phenomenon and the conventional description as used by climate extremists is at best NUTS. It’s sole purpose is to dumb down the atmosphere to focus on CO2 and in doing so it completely ignores basic physics. Because how can you talk about “trapping” when the surface IR only travels a few meters upwards before being absorbed whatever the concentration?
A far better conceptual approach is to think of it as the effective height from which IR is emitted to outer space is changed by the addition of CO2. So, that as the concentration of CO2 increases the average height at which CO2 bandwidths are emitted to space gets higher because the atmosphere is more “opaque”.
To use an analogy – in a thinly planted wood, whilst you may not be able to see the other side, you can “see” quite some distance in. But in a thickly planted wood, you can only see a short distance in. The difference is not whether or not you can see the other side (likewise talking about surface emissions is a complete red herring). What matters is how far into the wood/atmosphere you can see from outside.
The way this impacts temperature is not best described by “trapping” but instead by the adiabatic lapse from the average height of emissions down to the ground. The earth is (largely) at equilibrium with the solar heat coming in and heat lost to space. So, the temperature of the earth “seen” from outside will be constant. But because this height can change with the addition of so called “greenhouse gases” (and clouds) and because on average the lapse rate in our atmosphere is around 6.5C/km, , e.g. if the average height (of all wavelengths) moves by around 100m, then the average surface temperature will change by 0.65C
100
Mike, you might enjoy post 6, How the Greenhouse Effect Works, where we describe it along the lines you are saying and run with it.
40
David,
May I suggest that your resistor model be adjusted so the surface OLR pipe is the only from the surface. The surface OLR can then go down to the less then 40 W/m^2 as measured.
The other 200W/m^2 for powering the three pipes that generate/originate that OLR from their own atmospheric temperature as modified by latent heat of condensation are powered by insolation and all the other modes of heat transport from the surface. This also removes any need for expressing any ‘photons’ or energy all can be Watts or flux.
26
Will, it is tempting to make the circuit model more elaborate isn’t it?
However I only included it as a simple analogy for suggesting that when CO2 increases OLR can only increase in the other pipes, and in proportion to their resistance to change. In reality there could be funny linkages between the “resistances”.
20
Thanks David,
Yes more complex, otoh, the other methods of getting heat into the atmosphere are indeed the greatest flaw in those models. They all depend on surface radiation that is not happening. They also ignore the immense insolation generated within the atmosphere, not surface. One add point, change resistance to impedance, gets rid of ‘dissipative for heat’ to only heat, and allows reactive things like oceans.
47
Mike,
Consider that all CO2 exit flux originates at the tropopause independent of atmospheric concentration. This means that only the WV airborne water condensate levels control all other radiative exitance. Do the modelers have any idea of what may control/affect the atmospheric column water?
38
Thanks for your posts David. I have learned a great deal. Your re-routing feedback model seems quite straight-forward and intuitively correct. I hope your ideas and insights attract the attention they deserve among the climate science establishment.
40
Satellites clearly indicate that the OLR is far greater than that predicted by the conventional climate models. Read the following post from Hockey Schtick.
Thus, Trenberth’s “missing heat,” which only exists in falsified climate models, is not present in the atmosphere or oceans, and is now past Alpha Centauri located 4.3 light years away, i.e. it’s not “in the pipeline” and is never coming back.
100
🙂
30
The following quotes are from what Ferenc M. Miskolczi had to say in his 2010 paper
The Stable Stationary Value of the Earth’s Global Average Atmospheric Planck-Weighted Greenhouse-Gas Optical Thickness
These comments are built on his earlier works published in the following papers:-
Miskolczi, F. M. & M. G. Mlynczak (2004) The greenhouse effect and the spectral decomposition of the clear-sky terrestrial radiation IDŐJÁRÁS Quarterly Journal of the Hungarian Meteorological Service, Vol. 108, No. 4, 209-251.
Miskolczi, F. M. (2007) Greenhouse effect in semi-transparent planetary atmospheres IDŐJÁRÁS Quarterly Journal of the Hungarian Meteorological Service Vol. 111, No. 1, January–March 2007, pp. 1–40. http://owww.met.hu/idojaras/IDOJARAS_vol111_No1_01.pdf
40
Philip, unfortunately I do not know enough about the details of Miskolczi’s work to be sure, but at first blush what we are saying is compatible.
Can anyone expert in Miskolczi’s ideas shed any light on this?
[See also comment 43, below, for more on Miskolczi.]
110
David
Congratulations!
An “I don’t know” in the midst of a heavy technical discussion.
Maybe you’ll start a trend – but I doubt it.
60
I dug into FM. His core idea is similar to what has been posted so far. Unfortunately, his mathnhas been rather convincingly been shown faulty. I will dig out the reference and forward.
21
Rud,
His math is correct. His original explanation is incomprehensible to mere mortals. For the Noor van Andel explanation see:
http://www.eike-klima-energie.eu/uploads/media/EE_21-4_paradigm_shift_output_limited_3_Mb.pdf
All the best! -will-
30
Thanks Rud and Will. I seem to recall that Miskolczi’s core idea is that water vapor is the swing variable in the atmosphere, compensating for and substantially reducing the effects of changes in other GHGs. Certainly that is what is proposed here by the rerouting feedback (so far no maths in this approach).
10
Miskolczi reports some useful observations which are relevant here but concludes simply that the greenhouse effect needs reviewing.
David’s work is far more specific as to why Miskolczi observed what he did.
57
David,
Thank you for your reply. First a technical point, the link http:/owww.met.hu/idojaras/IDOJARAS_vol111_No1_01.pdf to Miskolczi, F. M. (2007) is correct but WordPress fails to activate it properly for some reason.
I like your identification and use of the pipe concept to explain the transmission of OLR to space. In particular the Surface Pipe is perhaps the easiest to recognise because its meteorological effect is so clearly involved in the generation of night time ground frost, this is particularly clearly seen when the surface air above the shallow inversion layer remains above freezing.
The AWS automatic meteorological station of Dome A in Antarctica used to provide clear examples of the generation of a surface inversion layer during the austral winter, but sadly this detailed graphic is no longer published on the web.
20
Thanks Philip. Link fixed. Yes, pipes are intuitive, formally an abbreviation, and the analogy is good.
00
Seems to me that the multi pipe method must be at work. If all pipes are held constant while global temperatures somehow increase then we have to imagine another mechanism to get that extra energy to space. There are not many credible alternatives. Lacking an alternative you get continued heat build up that is not seen. Might be discernable by comparing daytime/nighttime emissions of OLR.
40
Me being an interested layperson who is mainly ignorant of the complexities of the science and maths that Dr Evans describes in this series of posts,i can only gain an understanding via the use of basic analogies such as the pipeline description used. In that spirit of analogy am i correct in seeing the predicted tropospheric hotspot as a set of traffic lights on a highway that can delay traffic (radiation)from its journey into space ? is what Dr Evans saying is that rather than acting like traffic lights on a road that the troposphere acts like a road traffic island that has several exits and as one exit becomes congested the traffic (radiation) simply leaves the island via a different less congested route ? Is this why they havent been able to find the hotspot that their hypothesis depends so much on. thanks
40
This does not make sense. If there is more CO2 the pipe is “bigger”, thus able to absorb and emit MORE radiation to space.
30
Yes backslider, intuitively you have more CO2 molecules emitting from EL with a greater surface area, with a wider temperature difference between the surface and the emission layer, how on earth that’s going to result in LESS emission is beyond me, but that is what the models claim. David is just going with the model for now. Maybe he’ll comment on whether he actually agrees that more CO2 reduces cooling or not. It’s pretty key I think.
I always had this problem.
The models claim that more CO2 causes surface warming and lower stratosoheric cooling, that is: the average temperature difference between the surface and the stratosphere is increased. Thermodynamics tells me that in this situation the heat flux between the surface and the stratosphere will INCREASE. The models say it decreases.
That’s why satellites show that more CO2 has increased emission not decreased it. There is a fundamental problem here, it’s a bit like saying that when I put a bigger heatsink on my computer CPU and overclock it ( increase the CPU surface temperature ) the
Heat dissipated will be REDUCED. This seems like nonsense to me.
50
The “CO2 pipe” is the emission of OLR to space on the wavelengths at which CO2 emits and absorbs, from CO2 molecules. The analogy is one of a pipe carrying OLR to space.
When the CO2 concentration increases the CO2 blanket gets thicker and less radiation can escape to space by being emitted from CO2 molecules — because the CO2 emission layer moves higher, where it is colder, especially at some of the wavelengths in the wings of the CO2 well where the CO2 emission layer is in the troposphere. The analogy is that the CO2 pipe carries less OLR (so maybe it gets skinnier?) — that is, there is less OLR emitted from CO2 molecules.
41
Still not making sense here. To begin, CO2 is not a “blanket”. IR is absorbed at the surface level, more CO2 or not, then travels upward by various means. CO2 does nothing to hinder this process.
Really? How much higher and how much colder? Not very much at all I believe. If there are more molecules up there to radiate into space (following your reasoning as to what happens), then there will be more OLR from CO2. This has in fact been measured if you look at CERES data which indeed shows an increase in OLR.
00
Please read post 6 on how the greenhouse effect works.
At a given wavelength there is a top layer, about one optical depth in as seen from space, that is effectively where the OLR comes from at that wavelength. The temperature of the air there does much to determine the OLR at that wavelength — hotter objects (or gas clouds) emit more.
The CO2 picture is trickier because the middle of the “well” around 15 microns is in the stratosphere, where it gets slightly warmer as one ascends. However the main action as the CO2 concentration increases from current levels occurs in the wings of the well, where the EL is in the troposphere — more CO2 raises the EL and thus the EL gets colder.
About 20% of OLR is emitted by CO2 molecules. The Earth has warmed over the last few decades, so it is hardly surprising CERES finds increasing OLR.
Update: According to this article, CERES shows a decreasing OLR from 2000 to 2014. Ok, it hasn’t warmed lately. Later in the series we find the thermal momentum of the Earth is only a few years.
40
I think this is the point Backslider and I are trying to make. Please suspend your model perspective and park that for the moment and consider the hypothesis being put to you.
1. From an EMR perspective any photons received by the CO2 are going to be reradiated regardless of the height and temperature of the EL, why would IR flux be affected by this?
Now if we assume there is no shortage of photons, more CO2 means more excited CO2 molecules which means more IR photons emitted to space.
Put another way, the EL is higher the surface area emitting has increased by 4/3R delta R cubed – 4/3 R cubed, and the number of CO2 molecules per CC has increased. The number of emiting CO2 molecules and therefore photons emitted to space has to increase providing there is no shortage of upwelling photons.
Add to this that higher CO2 concentration implies that the frequency that collisions result in bond energies increasing such that photons can be emited (conversion of heat to IR) would increase (because there are more CO2 molecules per unit volume of air to collide with ). Upwelling convective heat is more efficiently radiated to space.
This would intuitively suggest that increasing CO2 aught to decrease pipe resistance in the same way that increasing the volume of copper in a wire does. Ceres data does suggest this happens.
10
bobl,
No. Only the top layer emits, and the curvature of the Earth is insignificant, so the “frontage” of CO2 to space remains about constant. Due to the rise of the CO2 EL in the troposphere at wing wavelengths, that part of the EL is colder, and on net increasing the CO2 decreases the OLR from CO2 molecules. According to the IPCC, a doubling of CO2 results in about 3.7 W/m2 less OLR emitted from CO2 molecules — this is based on spectroscopic observations, and although it has a fairly wide uncertainty, I have no reason to disbelieve them.
Note that we are only concerned with optical depth as seen from space on a given wavelngth, so the physical density of CO2 molecules as they go higher has little effect.
20
You just don’t get it. There are MORE CO2 molecules in the top layer!!
00
The Backslider: If the emission layer moved up 1 kilometer, its circumference around a spherical earth would increase by 2 * pi or about 6.3 km. The circumference of the Earth is 40,000 km. You can work out the spherical areas, but it just isn’t a significant factor.
The top “layer” is to one optical depth, so the density (molecules per surface area) of Co2 is much the same.
00
“The top “layer” is to one optical depth, so the density (molecules per surface area) of Co2 is much the same.”
Moving the CO2 top layer to one optical depth up one kilometer in the tropopause, reduces its temperature by how much? What part of the atmosphere has a surface area?
00
“Put another way, the EL is higher the surface area emitting has increased by 4/3R delta R cubed – 4/3 R cubed, and the number of CO2 molecules per CC has increased. The number of emitting CO2 molecules and therefore photons emitted to space has to increase providing there is no shortage of upwelling photons.”
Only if the molecules/volume N/m^3 remain the same! Both pressure N/m^2 and density N/m^3 decrease logarithmically with altitude; courtesy gravity. Radiative exitance from that altitude m^3 decreases with altitude; but total exitance, including that from below always increases with altitude. There is no fantasy emission level!!
05
As the emissions layer moves higher wouldn’t the surface area increase allowing for increased OLR, augmented by the increased number of CO2 molecules available to radiate directly to space?
00
The curvature of the Earth is insignificant in this regard. The radius of the Earth is 6,400 km, and the top of the tropopause is 17 km up in the tropics (where it is highest).
10
Are there any measurements that show CO2 exitance is from a lower temperature?
13
Theoretically, CO2 is a “greenhouse gas” in the sense that when the CO2 molecules are exposed to electromagnetic radiation, they absorb some of the energy in a frequency range. Some of this radiation energy causes CO2 molecule to vibrate and this should theoretically heat up the atmosphere by collisions with other molecules. Vibrating CO2 also emits infrared (IR) radiation in all directions, now with a lower frequency than the incoming, because some of the incident radiation energy is converted to heat energy (radiation energy of a photon E = h * f where h is Planck’s constant and f is the frequency). Outgoing radiation then has lower energy and consequently lower frequency. A more correct term of “greenhouse gases” such as CO2, H2O, methane, ozone, are infrared active gases (IR gases) because they absorb infrared (IR) radiation and also re-emits radiation at a lower frequency when any of the incoming radiant energy goes into heating (total energy must be constant):
Radiant energy Ein: = h*fin= h*fout + heat energy => fout < fin
Then fout radiation can find its way through other “pipes”.
Absorption and reeimisjon goes on continuously up through the atmosphere from molecule to molecule, and more and more radiation energy will be absorbed with a corresponding reduction in radiation frequency (radiation become "colder"). It is "cold" radiation which finally radiates into space from Earth. The radiation corresponds to a temperature of – 18 degrees C, the temperature at 5-6 km upper troposphere and represents dominant radiation from the earth and atmosphere.
As explained by prof. Claes Johnson, “cold” radiation toward a warmer surface cannot by itself increase the temperature of a warmer surface, ref. “Computational blackbody radiation” https://computationalblackbody.wordpress.com/
The absorption of radiation also follows the Beer-Lambert's radiation law indicating that more CO2 means that absorption takes place faster over a shorter distance (logarithmic relation). There cannot be more absorption when all radiation that can be absorbed is absorbed (comparable to light in fog where more fog gives absorption of light over a shorter distance).
CO2 is only a “greenhouse” gas in the context of being added to real greenhouses to enhance plant growth.
10
No,
The molecule receives a Photon which elevates an electron, it does not change its velocity (heat). There is no little bit that becomes heat. When it emits the photon it will have exactly the same energy (frequency) as the incoming photon.
Or
The molecule recieves a photon resulting in an elevated electron (bond vibration), the molecule collides with an other molecule and the energy of the vibrating bond is dissipated (shared to the colliding molecules) within the collision and the ENTIRE energy of the original photon is converted into translational velocity of the colliding molecules.
You are presuming here that the CO2 has a broad spectrum because some of the photon energy is converted to heat, but this is not true. CO2 has a broad spectrum because each molecule is traveling in a random direction and speed relative to the sensor, when the photon is emitted at a precise frequency from the CO2 molecule there is a doppler shift at the sensor depending on the relative motion between the molecule and the sensor. The sensor sees f(bond) +/- doppler shift.
20
That is the claim, with no evidence to support any CO2 radiation not related to its own kT/t thermal power!
05
Photons have momentum, you cannot emit what was absorbed unless the photon was emitted in exactly the same direction with the probability of 1/infinity. Return of the molecule to its unexcited state must occurs through a number of emission/thermalisation steps, or you violate conservation of momentum.
10
This issue is at the heart of comments I’ve been making in the blogosphere for years.
If the lapse rates change then convection also changes all along the lapse rate slope in order to negate the effect of GHGs via rerouting of the radiative flows.
A steeper lapse rate speeds up convection whereas a shallower lapse rate slows it down and the effects are opposite in lower levels as compared to upper levels and in columns of ascending air as compared to columns of descending air.
There is then no need to invoke an overall net change in surface temperatures at all, merely an equal and opposite change in the surface temperatures beneath rising and falling columns which are then neutralised by lateral surface winds.
As Jo says:
“Potentially, this blows everything away.”
108
“A steeper lapse rate speeds up convection whereas a shallower lapse rate slows it down…”
—
so far, so clear. However, I find the rest confusingly worded.
00
Regarding the CO2 pipe when CO2 concentration is increased:
1. In the centre of the band, from wavenumber 630 to wavenumber 710, there is no increase in absorption of surface radiation – radiation in this band is already completely absorbed by CO2 in the atmosphere.
2. In this band, there is an increase in radiation from CO2 to Space in all the tropical regions – approximately half the planet. In the remainder there is no change. This is because radiation in this band is coming from above 15km.
3. It is only in the wings of the CO2 band that the conventional Greenhouse Effect applies. Here the radiation from CO2 to Space is coming from below the tropopause, so an increase in CO2 will reduce the radiation to from CO2 to Space.
00
Yes. The last diagram on Barrett-Bellamy page 21 is illuminating in this regard.
00
That diagram has only the intent to confuse understanding of just what CO2 absorbs and emits at the pressures and temperatures of the tropopause!
29
Hi David
Obviously the lower diagram, without CO2, is an estimate and I suspect from reading the start of the outline that BOTH diagrams
are constructs of the author.
I would be concerned about whatever conclusions he might draw from experimental data which he has made up based on a limited range of
theoretical detail of the behaviour of the atmosphere.
KK
00
“… It is only in the wings of the CO2 band that the conventional Greenhouse Effect applies…..”
Dr. Happer found the model is mucked up for those wings. His lecture and slides are very useful addition to this discussion.
Slide 22: Lorentzian line shape nor Voigt line shapes are correct in the far wings! (and see slide 33.)
The overlap with the pure-rotational band of water vapor eliminates most of the response from the lower band edge, and IR from clouds further reduces the response to more CO2. The true response is likely less than half the ideal limit or a doubling is less than 3.7Wm^2″
Audio and slides of the physics lecture
http://www.sealevel.info/Happer_UNC_2014-09-08/
video http://jlf.streamhammer.com/speakers/williamhapper090814.mp4
Also see Slide 16, The thunderhead anvil FTIR satellite spectrum is top right graph. The BOTTOM CURVE just above the X axis. In other words water, as liquid and ice, blocks almost all outgoing IR. The other four spectra are cloud free spectra for the tropical west Pacific, Sahara Desert, Southern Iraq and Antarctica.
10
Gai, for the purposes of this blog post series (about failures of the architecture of the conventional basic climate model and the computation of the ECS with an alternative model with improved architecture), we are going with the establishment (AR5) values of parameters such as how much a doubling of CO2 reduces the OLR in the CO2 pipe (namely 3.7 W/m2).
00
In 1990, Moore and Kahanna published a paper giving the IR absorption wavelengths for H3CO3 formed by the proton irradiation of H20 and CO2 in thin layers of ice. Increased atmospheric CO2 increases its concentration in the upper atmosphere where such thin layers of ice are formed as ice crystals in high level clouds :
http://science.gsfc.nasa.gov/691/cosmicice/reprints/H2CO3-1.pdf
The IR absorption properties of ice in such clouds has been examined by Feofilov et al:
http://www.atmos-chem-phys-discuss.net/15/16325/2015/acpd-15-16325-2015.html
One can speculate that this may be a part of your rerouting mechanism as the latter find that changes in the IR values of such ice crystals can account for an increase in loss of energy to space of 2 W/m2 or more, and the ionization required could be linked to changes in the proton flux with changes in energy flow from the Sun with lower sunspot activity but an increase in solar flares.
http://www.scirp.org/Journal/PaperInformation.aspx?PaperID=36700
Note that these are just example references
20
Maybe, yes, there could be something like that.
The point of this post is that conventional climate model architecture creates a blind spot at this very point. It is intuitively “obvious” that there might be a feedback mechanism that takes place entirely high in the atmosphere, by which OLR blocked by increasing CO2 is re-routed out the water vapor pipe (or even the cloud tops pipe). If such a mechanism exists, it has huge implications for climate sensitivity to carbon dioxide.
But since it is neither a forcing or a “feedback” (to surface warming), this mechanism is not even on the radar of conventional climate science, due to faulty model architecture.
Someone is going to figure out exactly how this mechanism works: it’s potentially pretty important.
50
sounds like a horde of Maxwell’s Daemons … 🙂
00
This thinking is flawed. CO2 does not “block” anything. I behaves the same as any other greenhouse gas. More CO2 will mean more CO2 to radiate into space. Sure, some OLR may be re-routed by the water vapor pipe, however the CO2 pipe will also be enhanced.
CO2 itself has a negative feedback.
00
No, an increased concentration of atmospheric CO2 means less OLR from CO2 molecules. That’s what all the fuss is about. That part is basic physics based squarely on spectroscopy.
While there are more CO2 molecules, those beneath the emissions layers on average do not produce OLR because, on average, their emissions towards space are absorbed by those CO molecules above them. So, more molecules emitting, but no increase in OLR — in fact less, because the top layer of emitting CO2 is, on net, effectively colder.
00
“No, an increased concentration of atmospheric CO2 means less OLR from CO2 molecules. That’s what all the fuss is about. That part is basic physics based squarely on spectroscopy.”
Indeed! Spectroscopy that is the inverse conjugate of how atmosphere works! In order for CO2 to absorb at 15 microns it must be at a 15 micron temperature less that that of the emitter, else it is inert or emitting not absorbing.
While below temperatures are higher, the actual temperature at any level in the troposphere is higher than that of radiative equilibrium, as provided by gravitational lapse rate.
Earth’s atmosphere does not now, nor ever has, since the creation of WV have any kind of Radiative Greenhouse Effect.
All the best! -will-
04
apologies for interrupting but,for those interested, a number of new links worth checking have been posted at jo’s previous ‘”green” cars’ thread.
30
If you perturb the atmosphere with some extra infrared-active molecules (CO2) then they will have an effect on every heat-related thing going on, which is why you need a physics-based GCM to sort out the net effect, it cannot be done by waving hands.
The existing physics-based GCMs may well be making some poor approximations, and have some poor approximations forced on them from using coarse sampling, but they should already be dealing with heat transfer from CO2 to water vapour molecules, the net effect probably showing up in the water vapour and lapse rate feedback figures.
04
“Leave it to a GCM”? The GCMs have an architecture that leaves them blind to certain realities. Hmm, maybe that’s why they didn’t predict the “pause”, and couldn’t “predict” the medieval warm period?
60
Condensing the text of the last two posts down to such a short summary may seem to trivialise it, but it is important for communicating the essence of the idea.
After the next two posts have explained the H2O rerouting mechanism and the supporting evidence for it, that’s when it’s time to take the essence of the idea to the masses. You will need a tweet-sized version of this post. May I humbly suggest:
That should get tongues wagging.
60
“#CO2 shifts heat to stratospheric water vapour, making cooling feedback that’s not in @IPCC_CH model”
OR
#CO2 shifts heat to stratospheric microscopic ice, highly reflective at high insolation frequencies, making cooling feedback that’s not in @IPCC_CH model
35
Andrew: Yes, we need short messages. Not sure about the “stratospheric”, because all the water vapor is in the troposphere. How about
00
Oh, err, right, well, wagging for all the wrong reasons perhaps. 😐
Glad we sorted that out before tweeting.
00
I think you have simply stated that but not established it. Please identify the fatal flaws in this 200 page description of a GCM that Rud Istvan has cited:
http://www.cesm.ucar.edu/models/atm-cam/docs/description/description.pdf
09
Mikky, you tell us “the fatal flaws” in this 200-page description. We-all have much better ways to spend our time, and this request seems more to distract and dilute the real essence of this conversation than to advance it. In fact, it seems petulant. If you really want a constructive exercise, apply the content of this series to the description cited, and see if it fits. That would actually advance the conversation (and might even keep you quiet for a while).
And at a more nuanced level, what David is doing here is not about “proof” or power, but about insight into a psychological and social (i.e., political) situation that is about judgement and perhaps even compassion into difficult and complex matters (in which “science” is but a small part). Sophomoric rhetoric posturing for status (even if only self-myth status) is not a contribution.
110
Thank you! 😉
40
Read the post.
10
Why? 🙁
00
I will give you two flaws in that NCAR CAM3 documention. You judge whether fatal. First, full of partial derivatives of dependent variables. Second, suspect parameterizations of them. Over at WUWT, I used deep convection and the partials that effect Lindzens detrainment as an example in an arguement with Eschenbach.
And in essay Models all the way Down in my ebook, used modeled ice clouds (cirrus, mainly but not only) as the visual illustration comparing several GCMs to satellite observations in a peer reviewed paper referenced. Proving that the GCMs are not getting these clouds, and by inference detrainment, and by further inference deep convection, anywhere close to correct. And deep convection is fundamental to the water vapor feedback, especially in the upper troposphere where it matters most.
50
Do you mean partial derivatives WITH RESPECT TO dependent variables? These simply reflect the chosen laws of physics, which in ALL cases are unambiguous, once a choice has been made.
No dispute that many of the chosen laws in climate models are probably inadequate.
But David has made a claim about architecture, without providing any justification for that claim.
012
The partials are in respect to changes in surface temperature. Surface temperature is never ever an independent variable. There is never any reason to express a partial in respect to the total aggregate, unless the only intent is to deceive! All of the fake/falsified climate models have this enduring characteristic. 🙁
55
Mikky, good to see your nonsense is up to its usual standard 🙂
I proved it. In posts 2 and 3 I fully described the conventional basic climate model. In post 5 I noted that said model omits feedbacks other than those in response to surface warming. And in this post I demonstrated the possibility, indeed highly probable existence, of a particular feedback that is in response to increased CO2 in the upper atmosphere, and not in response to surface warming. Other such feedbacks could, and almost certainly do, exist.
The rerouting feedback is, obviously, omitted from the conventional model. Indeed, in terms of the conventional model, the rerouting feedback is neither a forcing (for it is not some independent actor influencing climate) nor a “feedback” (to a surface warming), so it cannot exist in the conventional architecture. As blind as.
(Lucky, Rud has gone thru’ that document for me.)
40
Yes, the big one that you seem to have forgotten:
10
See comment 28.1.2.1.
00
David I’ve had second thoughts about this. It’s actually quite a pertinent question as to why current climate models don’t show this water escape route.
The first problem with the “GCM architecture” argument is that GCMs don’t even enter into it, because you’re talking about a region above the tropopause, above the clouds, where water vapour is very rarified but CO2 is still ~395ppm, and the heat transfer becomes dominated by radiation rather than convection. In other words, the extra complexities of GCMs are unnecessary, a plain radiative transfer model should show the effect if it is even possible. Because RTMs predict spectra that always match measurements everywhere they’ve been tested, the RTMs are correct. Radiative transfer really is a solved problem. And an RTM is one component of every GCM.
So to get out via water, if I understand your suggestion correctly,
1. the surface OLR is absorbed by CO2,
2. it’s re-radiated uniformly by CO2 at a wavelength shared by H2O,
3. then some nearby H2O absorbs it,
4. the H2O emits it uniformly again from any one of a range of wavelengths, and since H2O has many spectral bands that don’t overlap with CO2, this radiation is probably able to make it to space. That’s the re-routing (or the Perth Four-Step as this photon dance may be called one day.)
In other words, to give energy an express elevator it relies on the Effective Radiating Height for H2O bands to be below the Effective Radiating Height for CO2 bands, which seems to be true. But that fact cuts both ways. If the H2O is rarefied enough that IR emitted in H2O-compatible bands at that altitude can probably reach space then the CO2’s IR of step 2 probably will not be intercepted by H2O.
H2O is a strong absorber everywhere that CO2 is a strong absorber, with the exception of 15±1μm where CO2 is at least 20 times more powerful according to HiTRAN. Especially at the cold altitudes involved here the 15μm band is the only relevant band. The fact that 15μm can be strongly emitted by CO2 and weakly absorbed by H2O makes the radiative transfer from CO2 to H2O even less likely, on top of the problem already posed by the relative lack of H2O at these altitudes.
Probably the transfer from CO2 to H2O doesn’t happen, no re-routing.
If this is not actually a problem for the Perth Four-Step then where has my counterargument gone awry?
The RTM predictions for TOA OLR match what is observed by satellite almost exactly, so this rerouting should be quantifiable and testable in RTMs. I’ve never heard of an RTM simulation showing H2O picking up the slack from water vapour on the OLR, and that would certainly dampen Houghton’s explanation of the GHE if it occurred.
What hope is there for re-routing?
00
Andrew: There are several misunderstandings in your comment. In brief, RTMs in GCMs do not incorporate the rerouting feedback because it is a feedback in response to local warming and possibly lapse rate changes, and it happens in the upper troposphere.
The main area where the emission spectrum changes as CO2 increases is out in the wings of the 15 micron well, where emissions to space come from the upper troposphere — so let us focus just on the upper troposphere. We are still in the convective region, below the tropopause, and there is water vapor present (though not in sufficient density to almost certainly prevent emissions from water vapor from reaching space).
As CO2 increases, on a time scale of decades, the CO2 emission layer in the upper troposphere ascends, so it gets colder, so it emits less OLR. This is the “thickening of the CO2 blanket”; less OLR is emitted from CO2 molecules. Thus CO2 removes less heat as OLR from the upper troposphere; thus there is local warming in the upper troposphere.
The idea of the rerouting feedback is that this local warming could induce more OLR from water vapor. This increase in OLR from water vapor is a feedback in response to an increase in CO2, but not a feedback in response to surface warming, so it is a feedback that is omitted from the conventional basic climate model (and presumably also from the GCMs), as per post 5. Thus some or all of the heat blocked from escaping to space as OLR from CO2 would escape instead as OLR from water vapor, and this process could take place in the upper troposphere with little or no involvement of the surface temperature.
Furthermore, the water vapor emission layer, which averages about 8 km, would descend on average if the lapse rate was constant — to emit more OLR the average WVEL height would have to be a little warmer and thus to descend.
I’m not principally making a GCM argument. This series of blog posts is about basic climate models, the application of “basic physics”. The importance of this is described in post 1, and the conventional basic climate model is fully described, as per the leading textbook and papers, in posts 2 and 3. As it happens, GCMs have some of the same architectural features — e.g. feedbacks to surface warming, forcings.
As we will show later, this rerouting feedback (or something with the same broad characteristics just outlined) is potentially quite significant, not a small player. If it were somehow a side effect of the RTM in the GCMs, someone would have noticed.
The Perth four-step (good one!) is not just a photon dance, because it probably involves thermal collisions too (though CO2 and H2O could exchange energy on shared wavelengths I suppose — one can dream up various schemes for transmitting energy from the CO2 population to the water vapor population).
00
Would it not be that if the CO2 were to emit photons at water vapour frequencies these same photons would be re-emitted in general, at the same frequency and have the same probability of being absorbed as it would when emitted by the CO2 molecule in the first place. The “pipeline” through the water vapour must surely be one which arises through the heating of the air sample by absorption by CO2, the energy going to air molecules which then excite water vapour molecules at a frequency which is more free to escape to a higher level.
00
John: Yes, the most interesting path for the energy is
1. via photon, absorbed by a CO2 molecule
2. via thermal collision(s), to a water vapor molecule
3. via photon, to space (in general at a different wavelength to the photon in 1).
If there is extra CO2, the CO2 molecules in the volume near the previous top of the emission layer at a given wavelength will be getting more back-radiation (absorbing more photons from CO2 above them) than previously.
00
A point.
“A pipe’s OLR is solely determined by the temperature of its emitting layer — the OLR in the surface pipe is determined by the surface temperature, the OLR in the water vapor pipe is determined by the average temperature of the water vapor emissions layer (WVEL) which in turn is determined by its average height and the lapse rate, and so on. Knowing the rearrangement of OLR between the pipes would allow us to know the change in OLR in the surface pipe, and thus the surface warming and the equilibrium climate sensitivity (ECS).”
If the average height increases, so should the area radiating. As you increase the radius of a sphere, it’s surface area expands…
00
Ralph, the curvature of the Earth is insignificant for this purpose — the radius of the Earth is 6,400 km and the troposphere is 17 km at its highest. So the “frontage” of CO2 to space remains about constant.
40
The frontage at the tropopause is a cross sectional area not a surface, especially important at low latitudes.
12
Dr Evans , now i have the time i want to mention a comment you made earlier in this thread were you say that CO2 does not have much effect on UV radiation coming in to the atmosphere from the sun , whilst true its worth mentioning that the indirect effects of CO2 on UV are a fundamental flaw ( the hole in the doughnut)of the IPCC CO2 greenhouse gas theory . Lord Monckton amongst others has shown that the IPCC scientists don’t claim that CO2 alone can cause dangerous warming , rather they claim that CO2 in the tropics causes extra water vapour and increased cloud cover which because its a more powerful greenhouse gas greatly amplifies the warming that would result from CO2 alone, their most important positive feedback. What they don’t point out is that cloud tops are white thus have a strong albedo effect, so if CO2 can increase cloud cover it indirectly increases the amount of UV thats reflected back to space preventing more UV from reaching Earths surface and warming it and less IR long wave to be trapped by greenhouse gasses, a negative feedback and thus a fundamental flaw ( a doughnut sized hole) right in the middle of their greenhouse gas/positive feedback theory
20
doubting dave, yes what you mention is very relevant and we will be covering these topics in some detail in the posts ahead.
20
Ok you proffer H20 and I would not argue against it. But I in my gut still think the dust and dirt are major players in clear air. Dust and dirt are major emitters of the energy. But it may be dust and dirt are major players is more ice and water droplets.
I like the resistors, how about potentiometers with diodes with zero forward bias. Then the caps for delay response.
An EE is an applied physicist of the invisible.
00
Oh goodie! Consider oceans and airborne water condensate to be capacitors of sensible heat. WV as inductors of heat in the temporary storage as latent heat of evaporation. Let’s have 24 (one/hr) equatorial 24hr LC resonance circuits sinusoidally changing from airborne water condensate (early morning) to WV (late evening). How is insolation power being distributed by the atmosphere? BTW I am not a proponent of electric universe, but the thermodynamics folks seem to refuse to consider resonance, yet overdriven resonance is mostly what breaks things like climate! 😉
15
I’m having trouble envisioning the proposed mechanism. Please let me know whether I’m warm or cold (so to speak) as I grope toward it:
CO2 concentration increases, so at a given altitude there are more radiators but a less-clear radiation path to space. So from that altitude total radiation from the CO2 molecules increases (because there are more radiators), but less of it escapes from that altitude directly to space (because more is intercepted by the now-more-numerous CO2 molecules above).
A consequence is the tendency for all gas at the altitude to warm. So the H20 molecules, of which the concentration at that altitude has not (initially) changed, radiate more (as would the CO2 because of the higher temperature) but the wavelengths the water molecules radiate at are largely those for which the increased CO2 concentration has not much affected the route to space.
Am I okay so far? At first blush this seems plausible, although I’m not yet convinced I’ve been able to think it through completely.
But then—and this part gives me particular trouble—the water-vapor-emissions layer descends:
This seems wrong to me. The only reason why the water molecules are radiating more is that the enhanced CO2 concentration has resulted in their absorbing more (by radiation and conduction). So they’re more energetic rather than less, right?
What am I missing?
00
“What am I missing?”
Distortion of the lapse rate slope and consequent convective changes.
The thing is that the warmer water vapour and non radiative molecules (warmed via conduction from CO2 molecules) together with those warmed CO2 molecules (by direct radiative absorption) cause a less steep lapse rate slope at lower levels which results in less rapid convection from the surface so that the water vapour is not carried up as high before it condenses out.
It condenses out at a lower, warmer height and the condensate sends more OLR to space from the warmer location.
Observations show that the higher levels have indeed become less humid in response to CO2 warming at the lower levels. That CO2 warming appears to have been suppressing convective power at the lower levels.
The energy blocked by CO2 has been re-routed to OLR from water vapour at a lower, warmer, level.
Reduced convection will permit a warmer surface beneath a rising column but for a reason that can be explained later there is corresponding cooling beneath descending columns.
It is all about changes in lapse rate slopes driving convective changes that neutralise radiative imbalances.
88
Thanks Stephen, that seems to make sense and the empirical evidence about humidity is certainly as you say.
I viewed it more in radiative terms: if the water vapor is emitting more, the WVEL must be warmer. If the lapse rate was the same (and it’s not, quite — see Stephen’s reply above), that would require the WVEL to have descended.
24
It seems to me that you’re confusing cause with effect.
The reason why an effective emissions altitude would drop is that the absorber concentration is less, so the path to space is clearer. In view of the lapse rate, space would “see” a warmer altitude because it could “see” farther down into it. It’s the concentration, not the temperature, that affects effective emissions altitude.
At least to the extent that I’ve understood it, though, the mechanism you’ve described doesn’t make the path to space clearer; it just makes the water molecules radiate more. So, to the extent that what space “sees” is warmer, it’s because the same altitude is warmer, not because the emissions altitude has descended.
Again, you’ve said that the increased CO2 concentration causes the H2O molecules to radiate more, and as a group they would do that only because they are more energetic, not less.
00
Joe, the path to space could be clearer if the population of water vapor molecules is not as energetic, due to emitting more OLR. Less energy presumably means they would tend to not go so be high in the gravitational field. It isn’t clear, due to the quantum nature of emissions and without knowing the quantity of energy involved, whether the combined thermal collision from CO2, increasing emission of OLR, and more back radiation from CO2, raises or lowers the energy of the water vapor at the emission layer. Or it could be lapse rate changes. In any case, we can be sure that if the water vapor is emitting more, the WVEL must be warmer.
00
I appreciate your reply and recognize that you’re fielding a lot of questions, so I’ll just mention that my concern remains. It centers on the following:
It does seem correct that, however marginally, a decrease in total water-vapor energy would lower the water-vapor emissions layer. And it would be true that its losing more energy to space would tend to reduce that total energy—everything else being equal.
But for the energy loss actually to occur would require that whatever causes the increase in outgoing long-wave radiation from water-vapor molecules do so at least initially without a corresponding increase in power delivered to those molecules. As though the water vapor were in some pumped-up state before the carbon-dioxide-concentration increase, and the enhanced back radiation from that increase stimulated a fall from that state.
Now, let me emphasize that I profess no particular competence in the relevant radiation physics. In particular, I agree with this:
That is, it isn’t clear to me, either. But I’m still stuck at how that increase in radiation would occur without an increase in the power the water vapor absorbs.
Yes, for the same absorbed power the power that water vapor radiates directly to space can be increased by reducing the altitude of its effective emissions layer, but that altitude reduction could happen only by (1) reducing the water-vapor concentration, which at least as I understand it isn’t part of your proposed mechanism, or (2) reducing total water-vapor energy—presumably by at least transiently increasing its direct radiation to space.
In other words, the mechanism seems to be that the increased radiation from water-vapor molecules to space is caused by an increase in radiation from water-vapor molecules to space. To at least this layman, the manner in which that feedback loop gets started is a poser.
00
It’s a good point Joe. After thinking about it for a while along exactly the lines you describe (which distracted me from working out, which I had intended to do after all day answering comments), I came up with the second reply, which has ended up at 33.2.1.2.
I think this resolves the issue. We will be publishing a post by Stephen Wilde soon, which might help make the convection/lapse-rate/radiation interaction clearer.
In addition the water vapor population is reduced, again as pointed out by Stephen in 33.1. The Paltridge paper mentioned in the article is a review of radiosonde data, particularly the better, higher quality data since 1973, which shows the specific humidity has been dropping in the upper troposphere as CO2 increased over the decades. Paltridge explains it by extra water vapor due to surface warming being mainly confined to the lower troposphere and the consequently greater stability at low altitudes leads to less overturning and less transport of water vapor to the upper troposphere. That would involve a surface warming, so is not part of the rerouting feedback, however.
11
So get to the gym when you get up this morning; your public can wait.
10
Joe, My last reply needs improving.
From a radiative point of view, the rerouting feedback causes more OLR to be emitted from water vapor, so the WVEL must be warmer.
Although that’s the end result, as you objected, how does one get to that situation?
As you point out, the population of water vapor molecules would be more energetic, warmed by the heat blocked by extra CO2. If more energetic, presumably the water vapor would or could go higher against the gravitational field. Yet for the WVEL to be warmer it presumably descended, and empirical evidence is that the WVEL descends — but the purely radiative explanation is inadequate to explain a descent.
As Stephen Wilde points out, the resolution is in the lapse rate, which becomes less steep (at least locally) because less heat is being radiatively removed from the rising air by CO2, although this is partially (but not fully) compensated for by an increase in water vapor removing heat radiatively instead. This builds on the notion that radiative cooling steepens the lapse rate, by cooling air faster than otherwise as it rises.
That the local lapse rate is less steep allows the WVEL to both be warmer and to descend slightly (if it stayed at the same height it would be warmer, so it can do some combination of warming and descending).
21
Much obliged for the reply.
10
And then there’s also this:
http://www.breitbart.com/big-government/2015/10/01/global-cooling-discovery-may-scupper-paris-climate-talks/
“… the oceans are producing unexpectedly large quantities of isoprene – a volatile organic compound (VOC) – which is known to have a cooling effect on climate.”
Darn that isoprene! 🙂
30
How come these diagrams always show the heat (or photons or whatnot) going straight up? How does a photon know which way is up? Isn’t it equally likely to go in any direction? The earth is a sphere, but also one that’s bumpy and rough. Do climate models assume that photons always take the shortest path to space?
00
Electromagnetic radiative flux at any frequency is produced/generated when there is a difference in directional opposing radiative field strength. For thermal EMR flux at each frequency and in each direction; this difference in radiative potential is sometimes expressed as (Ta^4-Tb^4), the difference being the maximum magnitude of flux in direction, with the ± indicating which direction. This one way flux is the only thermal flux generated! It can go in any direction depending on the temperature environment in that direction.
All the best! -will-
15
jorgekafkazar, just for simplicity, and artistic license. I suppose the average from 9 o’clock to 3 o’clock is straight up (12 o’clock). Photons are massless and brainless; they have no idea which way is up. They just shoot off in a random direction when emitted.
10
Some folk are massless and brainless; they have no idea which way is up. They think that Photons just shoot off in a random direction when emitted. They have no idea of why, when, how, or in which directions thermal electromagnetic is released from an emitter. 🙁
04
Yes, David. Thank you for your reply. I understand that here it’s a graphic simplification. But if we’re looking at averaging vectors ranging from 0° to 180° (or 3 o’clock to 9 o’clock), each of those angles has a different distance to space. I guess I’m asking an implied question, i.e., how do climate models handle mathematically the varying radiative directions and distances from the surface to space?
For clarity to others: a photon rising at the 90° angle will pass straight up through approx. 40 km of atmosphere. One traveling at 0° to 5° (almost horizontal) will pass through an average of about 350 kms. Looking at the entire hemisphere centered at the point source, the average distance an emitted photon travels to space is about 128 km, not 40 km. [I’m neglecting the density gradient; the optical density also varies with transmission angle. I’m also ignoring the fact that a photon can’t pass through the ionosphere (>>40 km) without hitting a molecule, either.]
Do the models incorporate this geometry? They must, but I have to ask. It’s that kind of world, now.
00
jorgekafkazar, yes I understand the models used to calculate the reduction in OLR from CO2 molecules with increasing CO2 (reduced OLR in the CO2 pipe) do take that geometry into account. As does the Stefan Boltzmann equation, which integrates the underlying Planck law over all directions (and wavelengths).
00
Thanks again, David. My remaining quibble is that it’s my understanding that the integration of Planck’s Law is based on summing an infinite number of small, flat (i.e., perfectly planar) surfaces whose geometry doesn’t permit reabsorption of emitted energy. One can imagine pebbly or pockmarked surfaces on Earth that might imperfectly match that assumed geometry, creating a small, possibly negligible, error in the result.
00
David – This is great. To make sure I understand, let me put this in my own words.
In the basic model (and in the GCMs), they assume that when CO2 levels increase, there is no impact on the water vapor and cloud top pipes. If, in fact, there is a significant impact on either or both of these two pipes, then the models will exhibit unexplainable problems and no tweaking of parameters will fix them.
In this post, you theorize one potential impact on one pipe which could explain some of the errors seen in the GCMs.
In all of the billions of dollars spent looking at climate change, no one has done research into possible effects of increasing CO2 on anything other than surface temperature. So there is not any research into the assumption of increased CO2 levels having no impact on the water vapor and cloud top pipes.
Do I have it right?
10
Thanks Leon. You have some of it right, but may need to go back and read more of the posts to get more of the details right. This series of blog posts is a fairly full account; it’s not simple to summarize down to a page/post or two.
There is a blind spot in the conventional approach, because feedbacks other than to surface warming are ignored. The rerouting feedback proposed here is in that blindspot, so AFAIK there has been little or no research expended on such things. However there has been a lot of research into water vapor and cloud tops.
In the conventional model the feedbacks are such that when the OLR in the CO2 pipe decreases due to increased CO2, the OLR in the water vapor pipe also decreases — this is the water vapor amplification due to increasded evaporation as the surface warms) that multiplies surface warming almost threefold in their model — thus requiring the surface pipe to carry even more OLR. More on this in future posts.
20
This is false reasoning. More CO2 means more CO2 in the emission layer, meaning more OLR from the CO2 pipe. Common sense.
Your reasoning is telling us that CO2 somehow stops emitting in also an upward direction. It does not. The ratio of what goes upward is constant regardless of how much CO2 there is.
01
Nope. See comment 28.1.2.1.
10
It would be interesting to do a survey of climate scientists to see how many of them agree with the following statement:
Increasing CO2 levels have NO impact on clouds and water vapor.
I am willing to bet less than 97% of even climate scientists will agree with that statement.
30
Would you accept the only correct answer, with personal integrity intact, in every case; “I do not know; nor does anyone else”? 😉
43
Will – I would accept that answer; in fact, it is my answer. But that answer would not be I agree. As I understand, David’s set of posts this statement is an assumption embedded in all of the GCMs.
So if we do not know the answer and David’s posts correctly outline how GCMs work, then our confidence in the GCM projections must decline significantly.
80
Davids articles clearly show that all models make use of partial derivatives with respect to surface temperature, the eventual aggregate of all model variables. This is a very very serious mathematical mistake. Serious enough so that it can not be inadvertent. Such must be intentional deceit!! 🙁
35
Leon, I think that they would all say that increasing CO2 does have some effect on water vapor and on clouds. So would I.
20
David, you said in the previous post that many people felt intuitively that there was something wrong with the greenhouse gas theory.
You have helped me to identify what that something is. I used to spend ages thinking through all the mechanistic possibilities including the subject of this post.
What I didn’t realise is that the modellers left many of these possibilities out of their models. I never considered that side of the argument before. I suspect you are going to reveal more of these omissions and I can guess some of them already.
80
The myth that CO2 TRAPS heat in the atmosphere is an oversimplification created to convince the public that rising CO2 will cause global warming. CO2 both absorbs thermal infrared AND EMITS it. To a first approximation, doubling CO2 doubles absorption AND doubles EMISSION. Increasing CO2 increases the number of photons traveling through the atmosphere and shortens the average distance each photon travels. The GHE arises from a combination of these partly compensating mechanisms. “Trapping” is a myth.
The upper atmosphere actually loses more energy by radiation from CO2 molecules than it gains by absorbing radiation. That creates an upper troposphere that is so cold that the lapse rate to the surface is unstable and convection makes up the net energy deficit produced by emission and absorption of radiation by CO2. And when less convection is required, the surface of the planet warms. You can read about GHG mediated heating and cooling rates at various altitudes in the atmosphere in Grant Petty’s “A First Course on Atmospheric Radiation”, an excellent text that costs about $40 from Amazon.
The interaction between radiation and GHGs is quantified by the Schwarzschild equation. As radiation of intensity I_0 at a given wavelength passes a incremental distance (ds) through a GHG, the net change intensity (dI) produced by emission of photons traveling in the same direction (first term) and absorption of photons (second term) is given by:
dI = n*o*B(lambda,T)*ds – n*o*I_0*ds
where n is the density of the GHG, o is the absorption cross-section at that wavelength, B(lambda,T) is the Planck function and T is the temperature of the increment ds.
At altitudes where I_0 is greater than B(lambda,T), increasing the density of of the GHG (n) makes dI more negative. Since upward radiation is usually emitted from where it is warmer, I_0 is usually greater than B(lambda,T). This is the real GHE. When the absorption cross-section is high, photons traveling upward must have been emitted only a short distance below where the local temperature T’ is similar to T. In that case I_0 = B(lambda,T’) and the difference between the emission and absorption terms is small. dI changes little. This produces “saturation” of the GHE at strongly absorbed wavelengths. At altitudes where dI is negative, increasing GHGs (n) decreases upward flux and the lost energy is retained in the atmosphere.
David wrote: “From the point of view of heat in the upper troposphere, increased CO2 makes it harder to escape to space in photons fired from CO2 molecules, and therefore relatively easier to escape in photons fired from water vapor molecules.”
More CO2 molecules can’t cause the water molecules or the photons emitted by water molecules to “do” anything. More CO2 molecules will make dI more negative, leaving more heat in the atmosphere ONLY if convection of heat is unchanged! The only way heat is “re-routed” to the water vapor pipe is through a rise in atmospheric temperature, making the B(lambda,T) for water vapor bigger. In convective regions, the relationship between surface temperature and temperature in the upper troposphere (on the average) is fixed by the lapse rate. The upper atmosphere can’t warm and emit more through the water vapor pipe unless the surface warms too. In non-convective regions, your mechanism can operate. AOGCMs should be capable of handling your feedback mechanism.
20
Increasing CO2 blocks some OLR in the CO2 pipe — AR5 reckons doubling CO2 reduces the OLR in the CO2 pipe by about 3.7 W/m2.
The heat blocked by increased CO2 has an effect on water vapor, presumably though extra heat in the upper atmosphere, as you say. It also affects lapse rates — see Stephen Wilde’s comment at 33.1 — so the transmission to the surface of a temperature change at altitude may be partly or entirely broken. Thus the action could be mainly confined to the upper atmosphere (I doubt it would be entirely confined), with little effect on the surface.
If the lapse rate were constant, and the water vapor is emitting more OLR, then the WVEL must descend (to where it is warmer). More likely there is some complicated lapse rate effect that reduces the descent (typical negative feedback).
Yes, in principle the proposed rerouting feedback could be added to the AOGCMs — like in Fig. 1 of post 5, expressed via some fC parameter. However there’s more coming up, and this might not be sufficient.
21
Good comment. Very understandable.
KK
00
You missed this bit:
The ratio of what is emitted upward and what is emitted in any other direction does not change.
The fact that we have more CO2 in the emission layer means more OLR is emitted.
00
No, less OLR is emitted. See comment 28.1.2.1.
00
Hi David. Been with you so far, but couple of points I disagree with this time:
1) “From the point of view of heat in the upper troposphere, increased CO2 makes it harder to escape to space in photons fired from CO2 molecules” CO2 only absorbs IR at 15um which only occurs at -90 to -110 km above the earth which is way above the troposphere.
2) Space isn’t cold. It has no temperature as temperature is only a measure of kinetic energy and is not a measure at all of the amount of energy radiated through it. I think this is an important point because many people don’t understand what temperature is. IR bouncing around the atmosphere has no effect on temperature at all.
01
Rod, with due respect, at least your second statement is just silly. Night vision goggles used by US special forces are only one physical example.
As to your first point, please dig deeper into radiative transfer codes and SB. Then recalculate.
11
“Rod, with due respect, at least your second statement is just silly. Night vision goggles used by US special forces are only one physical example.”
Rus, with due respect, Just how do night vision goggles display atmospheric temperature? Electromagnetic radiation at any wavelength has no temperature whatsoever!
04
Rod, (1) CO2 absorbs from about 13 to 18 microns, and towards the edges of that range the CO2 emission layer is in the troposphere. As CO2 increases the emission layer moves up in the troposphere, which principally accounts for the decrease in OLR in the CO2 pipe — which for a CO2 doubling is about 3.7 W/m2. So less heat is being removed to space by emission from the CO2 molecules. So more is available to be emitted by the water vapor molecules instead. Hence the rerouting.
20
If you going to talk about pipes then you should use a (water) dam model.
Water (shortwave) flows into the dam in a daily cycle.
The dam fills up to a hight (temperature/OLR) where outflow matches the inflow over the 24 hour period.
You can now model different mechanisms on each type of outflow. For instance some outlets may restrict flows with increasing pressure while others may increase flows.
You can also have off dam storage of energy (absorbed energy converted to a non thermalised state, ie kinetic, latent heat ect) which increase temp by smoothing out the peak losses during maximum dam hight periods
10
Rob, The water pipe analogy works well: Partially block one of four outlet pipes from a pool of water or dam and what happens? The water backs up a little then reroutes out the other three pipes, with a slight rise in the water level behind the pipes.
The models here are for moves between steady states, on time scales of decades, so that ASR equals OLR (energy in equals energy out). But if you can operate without that relationship, I don’t see why pipes cannot be applied on shorter timescales.
10
Misunderstanding of the Global Temperature Anomaly from John Kehr
I can not connect to the URL because Word Press tosses this site into a black hole.
20
So, the decrease of heat energy emitted to space by increasing CO2 is compensated by an increase of emission of heat by water vapour.
Interesting!
Miskolczi theory explained;
The Earth’s atmosphere maintains a constant effective greenhouse-gas content and a constant, maximized, “saturated” greenhouse effect that cannot be increased further by CO2 emissions (or by any other emissions, for that matter). After calculating on the basis of the entire available annual global mean vertical profile of the NOAA/NCAR atmospheric reanalysis database, Miskolczi has found that the average greenhouse effect of the past 61 years (from 1948, the beginning of the archive, to 2008) is:
* constant, not increasing;
* equal to the unperturbed theoretical equilibrium value; and
* equal (within 0.1 C°) to the global average value, drawn from the independent TIGR radiosonde archive.
During the 61-year period, in correspondence with the rise in CO2 concentration, the global average absolute humidity diminished about 1 per cent. This decrease in absolute humidity has exactly countered all of the warming effect that our CO2 emissions have had since 1948.
Similar computer simulations show that a hypothetical doubling of the carbon dioxide concentration in the air would cause a 3% decrease in the absolute humidity, keeping the total effective atmospheric greenhouse gas content constant, so that the greenhouse effect would merely continue to fluctuate around its equilibrium value. Therefore, a doubling of CO2 concentration would cause no net “global warming” at all.
[See comment 21 above for more discussion of Miskolczi.]
23
Easy to read and interesting.
10
Transport by Zepplin,
Well that would certainly be compatible with the rerouting feedback. It is also compatible with the estimate of the equilibrium climate sensitivity (ECS) found later in this series. Interesting.
Does anyone know more about this, and what happened to that theory?
10
I’ve just noticed Miskolczi’ name mentioned earlier in this thread.
this is a link to the paper- very worth reading
http://www.friendsofscience.org/assets/documents/E&E_21_4_2010_08-miskolczi.pdf
23
David,
The fatal flaw in this part of your hypothesis is time. Resistance is instantaneous, atmospheric mechanisms have a multi modal and highly variable time factor. Your circuit immediately needs variable capacitors, transistors, quite a few rom chips, and even a micro-controller to have the vaguest chance of emulating biospheric interations. It is going to be interesting to see how far you go down this path before you arrive at coincidence with the most pessimistic analysis from IPCC, if serious science is your aim.
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BilB, in other posts David has made it clear that many of the factors involved are cyclic and interdependent.
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‘It is going to be interesting to see how far you go down this path …’
I’m waiting around for his lecture on cycles.
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BilB, You are jumping to conclusions. The resistor analogy is only an analogy — please read the two paragraphs that preceded Fig.1. Suggestions for more circuit elements are just silly. So stick around to see where this goes 🙂
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David,
It has gone nowhere meaningful yet, so I hope you intend to pickup the pace.
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Here’s one of your own analogies Dimbulb,
There’s a bucket under a dripping water tank and the bucket leaks the same amount out as the tank puts in then some bloke comes along and adds an extra drop of water every day – you warmists claim it’s the same as humans adding extra CO2 – but what you forget is that the planet’s carbon balance, like the water tank’s water balance, is finite.
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Just for a bit of fun, put a soda syphon charger in the refrigerator. Let it cool. When the steel container is 4C, what is the temperature of the CO2 contents?
Now hold it in your hand for a while. It will heat up. When it doesn’t feel cool anymore, what is the CO2 temperature inside?
You have now demonstrated that CO2 can be heated and cooled without any shortwave radiation being involved. Try it in the dark if you wish. Measure the amount of 15um radiation emitted by your skin in the dark. Hmmm.
Maybe CO2 can absorb and emit EMF at all sorts of frequencies. Crank your heat gun up to, say, 400C. The air coming out contains CO2. How come it seems to be indistinguishable in temperature terms (and emitted frequencies) from the rest of the air?
The attribution of magical properties to CO2 is just so much hot air. The proponents of such nonsense should be prosecuted for obtaining money by fraud if they attempt to receive Government funding based on such preposterous nonsense as the “greenhouse effect”, or any related fantasy.
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MASSIVE GLOBAL COOLING process discovered as Paris climate deal looms
‘Could explain recent disagreements’
http://www.theregister.co.uk/2015/09/30/massive_global_cooling_factor_discovered_ahead_of_paris_climate_talks/
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Interestingly enough, just such a mechanism is proposed later in this series when we move on to what did cause the recent global warming (as part of the notch-delay theory).
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Isoprenes are covered here
http://www.ipcc.ch/ipccreports/tar/wg1/140.htm
Small volume, short impact life, not a new atmospheric component, and no change of impact. In other words just because it is new to your knowledge, this does not mean a new climate influence.
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You didn’t read about the new discovery that the IPCC did not cover.
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http://www.theregister.co.uk/2015/09/30/massive_global_cooling_factor_discovered_ahead_of_paris_climate_talks/
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Oops, I didn’t see your post Janama
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David: Continuing over conversation abou re-routing feedback here. Planck response involves artificially and uniformly raising the temperature of the planet by 1 degK with 1XCO2 in an AOGCM OR raise a blackbody model (which does not explicitly include CO2) from 255 to 256 degK. You appear to be asserting that the Planck response in the presence of 2XCO2 is different than for 1XCO2. Is this reasonable?
The blackbody model isn’t sophisticated enough to compare 1X and 2XCO2. Planck response is always 3.8 W/m2/K and it comes mostly from the upper atmosphere.
The AOGCM experiments offer choices. We have a 1XCO2 world equilibrated to GMST of 288 degK and emitting 240 W/m2 of TOA LWR. We have a 2XCO2 world equilibrated to GMST of 288+ECS and also emitting 240 W/m2 of TOA LWR. Now we artificially and uniformly rise temperature everywhere by 1 degK in both worlds. In the 1XCO2 world, the model experiment has been run and OLR increases by 3.2 W/m2/K. The 2XCO2 world has not been tried with AOGCMs to our knowledge. If OLR doesn’t increase by 3.2 W/m2/K, the difference is “re-routing feedback.
Alternatively, leave GMST on the 2X planet at 288 degK and TOA OLR will be only 236 W/m2. This planet isn’t at equilibium. Not useful.
If you trust AOGCMs enough to detect such re-routing feedback, they aren’t missing it when making projections.
In the warmer 2xCO2 world, the CO2 “pipe” may radiate just as much heat to space as the 1X pipe, because the pipe is being supplied by a planet with GMST raised by ECS.
Too much hand waving for me.
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Why, in this model, does the h20 molecule only emit away from the earth? What process dictates that?
Wouldn’t it be a random direction?
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AM: Because we are only interested in OLR in this model — emitted photons that make it to space — because we are focusing on the input and output of energy to and from Earth, in order that we can estimate the change in OLR from the surface, and thus the surface warming.
Also, the OLR photons can exit at angles other than vertical, but this is just artistic license and for simplicity of pictures. We are ignoring emitted photons that are reabsorbed on Earth. Yes, photons are emitted by a molecule in a random direction.
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What percentage of the H20 molecules will emit into space?
At what point do you account for the H20 molecules that emit back to the earth?
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AM: “What percentage of the H20 molecules will emit into space?” No idea, not relevant to OLR.
“At what point do you account for the H20 molecules that emit back to the earth?” We don’t, explicitly. To find the surface warming, we just have to know what the change in OLR emitted by the surface is — because (a) a constant fraction of the emissions from the surface become OLR because they go to space via the atmospheric window, and (b) the amount of emissions (both OLR and those not making it to space) by an emitter is a function of its temperature.
We can calculate the change in OLR from the surface, when CO2 doubles, by knowing that overall OLR does not change (except slightly due to minor albedo feedbacks to surface warming), and how the OLR changes due to the other emitters — CO2, water vapor, cloud tops. Calculating residuals isn’t ideal, but it is good enough to set an upper bound on surface warming.
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So what happens to the H20 feedback radiation in your model? It looks to me like whether it’s C02 which is emitting radiation, or H20, they both put 50% towards the earth, and 50% towards space, so this is just a rearranging of the feedback sources.
When you add in the 50% back to the earth, you then would increase the OLR of the surface to account for the extra radiation into the system.
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AM: “H20 feedback radiation”? Not sure what you mean. “Water vapor feedback” is when surface warming causes increased evaporation which causes the water vapor emission layer (WVEL) to ascend, which causes less OLR to be omitted from water vapor, thus requiring the surface to emit more instead. Water vapor feedback thus amplifies any surface warming.
In my model the water vapor feedback is still there. See Fig 1 of post 13. The water vapor feedback is expressed in the feedbacks to surface warming as part of the solar response, which got rolled into the “M” factor — the ARTS multiplier, the in-line form of the non-albedo feedbacks (see Eq. (4) of post 13, Eq.s (5) and (6) of post 9, and Eq. (10) of post3).
Increasing CO2 does not change the total OLR (excepting minor albedo changes due to surface warming), it merely redistributes it among the wavelengths — less from CO2 emissions wavelengths, more from non-CO2 wavelengths. The water vapor feedback leads establishment climate scientists to say it also causes less OLR from water vapor molecules, requiring the surface to warm even more to emit all that extra OLR — hence the rapid surface warming in their models.
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Interesting hypothesis! However, isn’t water vapor’s “resistance” higher than CO2’s? You mentioned that the OLR takes the least path of resistance, so I’m confused how your hypothesis works.
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When the CO2 concentration increases, we know from spectroscopy that the OLR from CO2 decreases (by ~3.7 W/m2 per CO2 doubling). The question is then how that blocked OLR redistributes itself between the remaining pipes — the main ones being emissions from the the cloud tops, water vapor emission layer (WVEL), and the surface.
In that context the “resistance” of the CO2 pipe doesn’t enter the picture — only the resistance of the non-CO2 pipes. It is as if the Co2 resistance was increased by a rising CO2 concentration, forcing some current to seek other paths.
The conjecture is that the resistance of the WVEL is less than the resistance of the surface, so that much of the OLR that no longer goes out the CO2 pipe would simply reroute out the water vapor pipe (hence the surface barely warms). This is in very stark contrast to the establishment picture, which is that the water vapor pipe blocks OLR in sympathy with the CO2 pipe (water vapor amplification) so the large OLR increase is in the surface pipe, hence the surface warms lots.
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“we know from spectroscopy that the OLR from CO2 decreases (by ~3.7 W/m2 per CO2 doubling).”
When I read your previous article I was intrigued by your assertion that partial differential claims are inadequate. That makes sense given the fact that the climate is a chaotic system. Carrying that logic one step further it seems to me that spectroscopy is inadequate since it narrowly focused much like a partial derivative.
According to my thermodynamics text, another equation used to measure temperature change when more CO2 is present is Q = mcT. Using this equation and CO2’s heat coefficient c, I have discovered that one mole of CO2 warms up at a slower rate than the mole of O2 it replaces in the atmosphere. It also cools slower. Water works the same way. My guess is that CO2 and water vapor don’t really warm the atmosphere. When all variables are considered (not just spectroscopy), CO2 causes temperatures to be more stable: warmer nights, cooler days; warmer winters, cooler summers.
So taking Q=mcT into account, I’m not surprised that climate models get it wrong. It seems to me the science is narrowly focused on spectroscopy experiments.
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G.M. Jackson,
Your equation Q = mcT tells you how much kinetic energy is contained in a body of mass m and heat capacity c. You are on the wrong track by assuming that increasing the proportions of GHGs in the atmosphere would raise the overall energy content of the atmosphere significantly just because the specific heats of CO2 and of water are greater than those of non-GHGs such as nitrogen and oxygen. GHGs constitute such a tiny proportion of the molecules in the atmosphere that the effect would be negligible.
The claim that increasing CO2 and/or H2O causes surface warming is based on a quite different principle. Towards the top of the atmosphere where molecules are sufficiently rarefied, both CO2 and H2O act as coolants by radiating their energy to space. This is possible because, as the atmosphere gets progressively rarefied, the GHG molecules are increasingly able to radiate their energy away before they lose it in a collision with another molecule (or before it is absorbed by another GHG molecule).
But if the concentration of atmospheric GHGs increases, the atmosphere at each particular height becomes less rarefied than it was previously – so the heights at which the GHGs can successfully radiate increase. But at these increased heights the air is colder – so the molecules can only radiate a smaller amount of energy than before. Consequently, to maintain energy balance, the surface must warm, as will the rest of the atmospheric column, by an amount that exactly compensates for the increased GHG concentration, thus allowing the GHGs to radiate away exactly the same amount of energy as they did before.
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David Cosserat October 30, 2015 at 10:18 am ·
You claim EMR flux from the surface that gets attenuated by the atmosphere. where and when has such surface exitance ever beeh noticed, detected, or measured. The atmosphere not the surface radiates away all excess power. Surface temperature with any atmospheric lapse must always be higher than your fantasy calculation. you have absolutely no evidence that atmospheric CO2 in any way affects the radiative exitance or temperature anywhere on or about this planet
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“You are on the wrong track by assuming that increasing the proportions of GHGs in the atmosphere would raise the overall energy content of the atmosphere significantly”
You misunderstand me. Q=mcT doesn’t raise temperatures, It shows that CO2 warms and cools slower than the O2 it replaces. If you’ve ever lived near a lake or an ocean (water has a high c value), the average temperature does not change; rather, the temperature fluctuations are less volatile (e.g. warmer nights, cooler days; warmer winters, cooler summers).
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In that case I am at a loss to understand why you said originally: “According to my thermodynamics text, another equation used to measure temperature change when more CO2 is present is Q = mcT.”
Now you are saying ” Q=mcT doesn’t raise temperatures”.
It is certainly true that a higher thermal capacity c means it would take longer to warm a gas by a given temperature difference with a given rate of energy input.
I think you are imagining a system which is warming or cooling. In contrast, the system that David Evans is addressing starts out in steady state, neither warming nor cooling. Then extra CO2 is added and the system re-adjusts to a new steady state at a higher temperature, again neither warming nor cooling. David explicitly is not interested in how long it takes to transition between the two steady states. (And in any case, doubling atmospheric CO2, for example, would add negligible additional ‘thermal inertia’ warming delay because it constitutes such a miniscule fraction of the total atmospheric mass.)
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“I think you are imagining a system which is warming or cooling. In contrast, the system that David Evans is addressing starts out in steady state, neither warming nor cooling. Then extra CO2 is added and the system re-adjusts to a new steady state at a higher temperature, again neither warming nor cooling.”
I’m imagining that if more CO2 is added given Q in X amount of joules, the change in T will be less. T = Q/mc. Notice when either m or c are increased, T is less. I’m not sure why you or David believes the system is in a steady state. It warms and cools all the time. Check your thermometer at sunrise, then at sunset.
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You say: I’m imagining that if more CO2 is added given Q in X amount of joules, the change in T will be less. T = Q/mc. Notice when either m or c are increased, T is less.
My point is that in such a case doubling atmospheric CO2 would make a negligible difference to atmospheric temperature because, at a concentration of 400ppm, for every CO2 molecule in the atmosphere there are ~2500 other molecules across which the energy content change would be equilibrated.
You say: I’m not sure why you or David believes the system is in a steady state. It warms and cools all the time. Check your thermometer at sunrise, then at sunset.
In that case our conversation is at an end because you are disputing the basic premise that the earth system as a whole is in long term energy balance with the Sun. Both David and I and all the other commentators here, and the IPCC, and numerous other people who participate in such debates elsewhere (warmists included), are perfectly capable of discussing long term overall earth system energy balance whilst accepting that hourly, daily and annual fluctuations about a mean value occur all the time.
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I have a question I’d like to put to you re: the “four pipes.” I know it’s a metaphor but how is it possible in reality? It’s always been my understanding that CO2, water vapor, clouds, and the remaining atmosphere are mixed together–they’re not in separate compartments or pipes. A photon leaving earth has no choice but to go through a mix of molecules that are fairly uniform at every point of the atmosphere. Thus, the idea that there is a path of least resistance seems counter-intuitive.
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GM: A “pipe” is defined as the OLR from a given type of emitting molecule, which also implies that is over a small set of wavelengths. For example, the CO2 pipe is for all OLR emitted by CO2 molecules (which will nearly all be between 13 and 18 microns).
Heat finds it easier to escape the planet by some molecules than others under certain conditions. If you perturb the system, these “resistances” indicate where most of the OLR will go.
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“But if the concentration of atmospheric GHGs increases, the atmosphere at each particular height becomes less rarefied than it was previously”
I’m not sure what you mean by “less rarefied.” If you mean more molecules, I don’t see how that would be the case with CO2. When a CO2 molecule is added, and O2 molecule is subtracted.
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Close, but for the long-chained hydrocarbons in coal and oil it’s not quite 1:1.
C10H12 + 13 O2 ==> 6 H2O + 10 CO2 + heat
Slightly more molecules are released as products than were removed from the air. Both of the products are GHGs.
If we disregard the H2O which is not long-lived and simply rains out, the number of molecules is actually decreasing in this equation! So David’s remark about GHG increase meaning a denser atmosphere is not correct in practice.
But GHGs are only being added in this reaction, not removed. So his more essential point about GHG increase decreasing the transparency of the atmosphere to some key wavelengths is still correct.
Indeed it must be true, because we’re taking carbon out of the ground and putting it back in the sky where it originally came from. Industrial combustion is really the largest environmental restoration programme ever conducted, but nobody ever seems to call it that.
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G.M. Jackson,
Good point – assuming that the man-made CO2 molecule is made from an atmospheric O2 molecule. Perhaps I should have said: “…the atmosphere at each particular height becomes more concentrated in CO2 than it was previously.”
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