Guest Post by Willis Eschenbach
I’ve been reflecting over the last few days about how the climate system of the earth functions as a giant natural heat engine. A “heat engine”, whether natural or man-made, is a mechanism that converts heat into mechanical energy of some kind. In the case of the climate system, the heat of the sun is converted into the mechanical energy of the ocean and the atmosphere. The seawater and atmosphere are what are called the “working fluids” of the heat engine. The movement of the air and the seawater transports an almost unimaginably large amount of heat from the tropics to the poles. Now, none of the above are new ideas, or are original with me. I simply got to wondering about what the CERES data could show regarding the poleward transport of that energy by the climate heat engine. Figure 1 gives that result:
Figure 1. Exports of energy from the tropics, in W/m2, averaged over the exporting area. The figures show the net of the energy entering and leaving the TOA above each 1°x1° gridcell. It is calculated from the CERES data as solar minus upwelling radiation (longwave + shortwave). Of course, if more energy is constantly entering a TOA gridcell than is leaving it, that energy must be being exported horizontally. The average amount exported from between the two light blue bands is 44 W/m2 (amount exported / exporting area).
We can see some interesting aspects of the climate heat engine in this graph.
First, like all heat engines, the climate heat engine doesn’t work off of a temperature. It works off of a temperature difference. A heat engine needs both a hot end and a cold end. After the working fluid is heated at the hot end, and the engine has extracted work from incoming energy, the remaining heat must be rejected from the working fluid. To do this, the working fluid must be moved to some location where the temperature is lower than at the hot end of the engine.
As a result, there is a constant flow of energy across the blue line. In part this is because at the poles, so little energy is coming from the sun. Over Antarctica and the Arctic ocean, the sun is only providing about a quarter of the radiated longwave energy, only about 40 W/m2, with the remainder being energy exported from the tropics. The energy is transported by the two working fluids, seawater and air. In total, the CERES data shows that there is a constant energy flux across those blue lines of about six petawatts (6e+15 watts) flowing northwards, and six petawatts flowing southwards for a total of twelve petawatts. And how much energy is twelve petawatts when it’s at home?
Well … at present all of humanity consumes about fifteen terawatts (15e+12) on a global average basis. This means that the amount of energy constantly flowing from the equator to the poles is about eight-hundred times the total energy utilized by humans … as I said, it’s an almost unimaginable amount of energy. Not only that, but that 12 petawatts is only 10% of the 120 petawatts of solar energy that is constantly being absorbed by the climate system.
Next, over the land, the area which is importing energy is much closer to the equator than over the sea. I assume this is because of the huge heat capacity of the ocean, and its consequent ability to transport the heat further polewards.
Next, overall the ocean is receiving more energy than it radiates, so it is exporting energy … and the land is radiating more than it receives, so it is getting energy from the ocean. In part, this is because of the difference in solar heating. Figure 2, which looks much like Figure 1, shows the net amount of solar radiation absorbed by the climate system. I do love investigating this stuff, there’s so much to learn. For example, I was unaware that the land, on average, receives about 40 W/m2 less energy from the sun than does the ocean, as is shown in Figure 2.
(Daedalus, of course, would not let this opportunity pass without pointing out that this means we could easily control the planet’s temperature by the simple expedient of increasing the amount of land. For each square metre of land added, we get 40 W/m2 less absorbed energy over that square metre, which is about ten doublings of CO2. And the amount would be perhaps double that in tropical waters. So Daedalus calculates that if we make land by filling in shallow tropical oceans equal to say a mere 5% of the planet, it would avoid an amount of downwelling radiation equal to a doubling of CO2. The best part of Daedalus’s plan is his slogan, “We have to pave the planet to save the planet” … but I digress).
Figure 2. Net solar energy entering the climate system, in watts per square metre (W/m2). Annual averages.
You can see the wide range in the amount of sunlight hitting the earth, from a low of 48 W/m2 at the poles to a high of 365 W/m2 in parts of the tropics.
Now, I bring up these two Figures to highlight the concept of the climate system as a huge natural heat engine. As with all heat engines, energy enters at the hot end, in this case the tropics. It is converted into mechanical motion of seawater and air, which transports the excess heat to the poles where it is radiated to space.
Now, the way that we control the output of a heat engine is by using something called a “throttle”. A throttle controls the amount of energy entering a heat engine. A throttle is what is controlled by the gas pedal in a car. As the name suggests, a throttle restricts the energy entering the system. As a result, the throttle controls the operating parameters (temperature, work produced, etc.) of the heat engine.
So the question naturally arises … in the climate heat engine, what functions as the throttle? The answer, of course, is the clouds. They restrict the amount of energy entering the system. And where is the most advantageous place to throttle the heat engine shown in Figure 2? Well, you have to do it at the hot end where the energy enters the system. And you’d want to do it near the equator, where you can choke off the most energy.
In practice, a large amount of this throttling occurs at the Inter-Tropical Convergence Zone (ITCZ). As the name suggests, this is where the two separately circulating hemispheric air masses interact. On average this is north of the equator in the Pacific and Atlantic, and south of the equator in the Indian Ocean. The ITCZ is revealed most clearly by Figure 3, which shows how much sunlight the planet is reflecting.
Figure 3. Total reflected solar radiation. Areas of low reflection are shown in red, because the low reflection leads to increased solar heating. The average ITCZ can be seen as the yellow/green areas just above the Equator in the Atlantic and Pacific, and just below the Equator in the Indian Ocean.
In Figure 3, we can see how the ITCZ clouds are throttling the incoming solar energy. Were it not for the clouds, the tropical oceans in that area would reflect less than 80 W/m2 (as we see in the red areas outlined above and below the ITCZ) and the oceans would be much warmer. By throttling the incoming sunshine, areas near the Equator end up much cooler than they would be otherwise.
Now … all of the above has been done with averages. But the clouds don’t form based on average conditions. They form based only and solely on current conditions. And the nature of the tropical clouds is that generally, the clouds don’t form in the mornings, when the sea surface is cool from its nocturnal overturning.
Instead, the clouds form after the ocean has warmed up to some critical temperature. Once it passes that point, and generally over a period of less than an hour, a fully-developed cumulus cloud layer emerges. The emergence is threshold based. The important thing to note about this process is that the critical threshold at which the clouds form is based on temperature and the physics of air, wind and water. The threshold is not based on CO2. It is not a function of instantaneous forcing. The threshold is based on temperature and pressure and the physics of the immediate situation.
This means that the tropical clouds emerge earlier when the morning is warmer than usual. And when the morning is cooler, the cumulus emerge later or not at all. So if on average there is a bit more forcing, from solar cycles or changes in CO2 or excess water vapor in the air, the clouds form earlier, and the excess forcing is neatly counteracted.
Now, if my hypothesis is correct, then we should be able to find evidence for this dependence of the tropical clouds on the temperature. If the situation is in fact as I’ve stated above, where the tropical clouds act as a throttle because they increase when the temperatures go up, then evidence would be found in the correlation of surface temperature with albedo. Figure 4 shows that relationship.
Figure 4. Correlation of surface temperature and albedo, calculated on a 1°x1° gridcell basis. Blue and green areas are where albedo and temperature are negatively correlated. Red and orange show positive correlation, where increasing albedo is associated with increasing temperature.
Over the extratropical land, because of the association of ice and snow (high albedo) and low temperatures, the correlation between temperature and albedo is negative. However, remember that little of the suns energy is going there.
In the tropics where the majority of energy enters the system, on the other hand, warmer surface temperatures lead to more clouds, so the correlation is positive, and strongly positive in some areas.
Now, consider what happens when increasing clouds cause a reduction in temperature, and increasing temperatures cause an increase in clouds. At some point, the two lines will cross, and the temperature will oscillate around that set point. When the surface is cooler than that temperature, clouds will form later, and there will be less clouds, sun will pour in uninterrupted, and the surface will warm up.
And when the surface is warmer than that temperature, clouds will form earlier, there will be more clouds, and higher albedo, and more reflection, and the surface will cool down.
Net result? A very effective thermostat. This thermostat works in conjunction with other longer-term thermostatic phenomena to maintain the amazing thermal stability of the planet. People agonize about a change of six-tenths of a degree last century … but consider the following:
• The climate system is only running at about 70% throttle.
• The average temperature of the system is ~ 286K.
• The throttle of the climate system is controlled by nothing more solid than clouds, which are changing constantly.
• The global average surface temperature is maintained at a level significantly warmer than what would be predicted for a planet without an atmosphere containing water vapor, CO2, and other greenhouse gases.
Despite all of that, over the previous century the total variation in temperature was ≈ ± 0.3K. This is a variation of less than a tenth of one percent.
For a system as large, complex, ephemeral, and possibly unstable as the climate, I see this as clear evidence for the existence of a thermostatic system of some sort controlling the temperature. Perhaps the system doesn’t work as I have posited above … but it is clear to me that there must be some kind of system keeping the temperature variations within a tenth of a percent over a century.
Regards to all,
w.
PS—The instability of a modeled climate system without some thermostatic mechanism is well illustrated by the thousands of runs of the ClimatePredictionNet climate model:
Note how many of the runs end up in unrealistically high or low temperatures, due to the lack of any thermostatic control mechanisms.
I think my suggestion about separate (and independently variable) heights for the effective radiating level and the S-B level has considerable merit and deserves some more thought.
The radiative characteristics of constituent gases determine the effective radiation height.
The conductive capability of atmospheric mass determines the S-B height.
The air circulation (especially the size and speed of the convective overturning) reconfigures as necessary to ensure that the correct amount of energy is delivered from the S-B height to the effective radiating height thereby maintaining balance between radiation in and radiation out.
The idea of the effective radiating height moving towards the S-B height when radiative capability increases fits with my past suggestion that more radiative capability means that the circulation has to work less hard to move energy from the S-B level to the effective radiating level.
I think I am now very close to a definitive description.
Steven writes “I think my suggestion about separate (and independently variable) heights for the effective radiating level and the S-B level has considerable merit and deserves some more thought.”
The factors affecting the atmosphere that includes GHGs and the ERL is a separate conversation to the Willis thought experiment of course…
There is one other possibility that should also be examined.
What if the SB effective radiating surface always ends up at some specific fraction of the atmospheric column regardless of the gas mixture?
It would be reasonable at first blush, to consider possibilities like the effective radiating surface of an atmosphere is always at the point where half the mass of the atmosphere is below the surface and half the mass is above the surface. If such a median surface (or some other fraction of the atmospheric column) is always the same point where effective radiation occurs, regardless of the gas mixture then the specific concentration of GHG’s would be irrelevant.
It would take a bit of detailed dissection of atmospheric pressure curves on various planets (info we really do not have at this time in great precision, except earth and a very small sample of pressure profiles from venus, and mars. Then compare that to the altitude at which their actual temperature coincides with the temperature required by SB.
If the radiation behavior of a mixed gas atmosphere always self organizes in some similar manner then the specific concentration of CO2 or any other GHG would be pretty much irrelevant and we drop back to the lapse rate and surface warming being simply defined by the gravity and atmospheric mass and you could ignore the specific gas mixtures.
We also need to keep in mind that the planet and its atmosphere do not necessarily need to lose energy at IR frequencies. Some gasses radiate in the microwave band, planets with weather radiate a good deal of energy at radio frequencies, and some gases give up energy at visible frequencies due to florescence. Even in a thought experiment involving an IR in active gas, you would have to also eliminate all these other modes of emission to totally eliminate energy loss.
Only time will tell if those who are willing to actually investigate the pressure/gravity warming theory rather than just dismissing it out of hand will eventually either dig out the specific evidence to support the theory or actually falsify it after making a good faith effort to examine reasonable possibilities implicit in the concept required by conservation of energy considerations.
– Stephen Wilde says:
December 26, 2013 at 8:21 am
Pressure on its own does nothing.
What warms the surface above S-B is the amount of atmospheric mass available to absorb energy from the surface by conduction and the amount of work required to hold that mass off the surface against the force of gravity.-
Amount gravity determine how much work is done, it’s also related to how how quickly atmosphere
can transfer it’s kinetic energy [making warmth]. So gravity is related to how much and how fast atmosphere can gain energy and then transfer that energy back into heat.
The amount of atmosphere relates to size of battery- it quantity of kinetic energy which could be stored. It’s more about how long atmosphere stores energy.
So Earth duration is in terms “full discharge” is days, and Venus atmosphere is centuries.
So size of atmosphere is related to length of time it takes to cool at night or winter, but not much related to voltage. It makes it warmer by not having night cool as much.
And gravity is more related to how fast it charges and discharges.
Of course more atmosphere is also related to amount of insulation is put on the house. It’s possible to put so much insulation that it’s helping much. But all gases are good insulation- including CO2 or H2O gas. H20 water droplet is not as good in terms of insulation, but droplet
have a high specific heat- twice it’s gas per kg. So water in terms of insulation is like a brick house. A foot of brick wall will prevent a house heating or cooling quickly due daily weather warming and cooler. It has thermal inertia. Or having a thick stone roof works in deserts because keeps house cool in day and warmer at colder desert nights. Can be *better* than fiberglass despite fiberglass’s better insulative properties…
– Stephen Wilde says:
December 26, 2013 at 11:46 am
Actually the atmosphere is already ‘isoenergetic’ (is there a better word ?).
Molecules at the surface have the same energy content as those at the top of the atmosphere but as one goes up kinetic energy (heat) is replaced by gravitational potential energy (not heat).-
If talking about troposphere, I agree with this. Or if one is talking about most of the mass of atmosphere.
And do think one can mostly ignore the rest of it. It’s details of entire model. It seems, it could be needed for weather, less needed for global climate.
For instance the thermosphere has very energetic molecules but they are few in number and would be related to a rather insignificant details. In sum their energy is staggeringly impressive to the human scale, but to entire atmosphere, not really particularly important.
-That gives a neat reason as to why an isothermal atmosphere (same temperature all the way up) is not physically possible.
If it were possible then there would be the bizarre scenario of the energy content of individual molecules increasing with height.-
Yes, AGWers tend make many these impossible machines.
-The topmost molecules would be the same temperature as surface molecules but would additionally carry a full allowance of gravitational potential energy too.-
Which actually the case in regard to thermosphere.
-Such energy rich molecules high up would be rapidly lost to space because the gravitational field could not constrain them.-
Nope. Air molecule of troposphere do not travel anywhere near orbital or escape speed.
But ISS is flying thru Earth’s atmosphere- just a really, really thin atmosphere. Or Earth’s atmosphere extends to indefinite height, but people tend to put it at 800 km high, which twice
ISS orbital height. Or there is “air” up there that travels at very high speeds.
The Wake shield. Which was deployed by Shuttle which orbited around same orbital as ISS:
“Wake Shield Facility is an experimental science platform that was placed in low Earth orbit by the Space Shuttle. It is a 3.7 meter (12 ft) diameter, free-flying stainless steel disk.
The WSF was deployed in the wake of the Space Shuttle at an orbital altitude of over 300 kilometers (186 mi), within the thermosphere, where the atmosphere is exceedingly tenuous. The forward edge of the WSF disk redirected atmospheric and other particles around the sides, leaving an “ultra-vacuum” in its wake. The resulting vacuum was used to study epitaxial film growth.”
http://en.wikipedia.org/wiki/Wake_Shield_Facility
So it was making a better vacuum in what most people are happy to call a vacuum. The Moon has better vacuum than what the Wake shield could create. But anyhow gas is travel at velocity
of around 7000 m/s or near or over orbital speed which is about 7.8 km/second at LEO.
They have move fast or they fall. Or one have to be going somewhere north of 20 km/sec
to get anything you could call “buoyancy”. Though since solar wind particles are in region over 300 km/sec perhaps they could be seen as being “buoyant”.
Larry Ledwick (hotrod) says, December 26, 2013 at 3:27 pm:
“It would be reasonable at first blush, to consider possibilities like the effective radiating surface of an atmosphere is always at the point where half the mass of the atmosphere is below the surface and half the mass is above the surface. If such a median surface (or some other fraction of the atmospheric column) is always the same point where effective radiation occurs, regardless of the gas mixture then the specific concentration of GHG’s would be irrelevant.
It would take a bit of detailed dissection of atmospheric pressure curves on various planets (info we really do not have at this time in great precision, except earth and a very small sample of pressure profiles from venus, and mars. Then compare that to the altitude at which their actual temperature coincides with the temperature required by SB.”
It’s actually quite simple. The ‘effective radiating level’ of any planet is no more than a conjured-up illusion. The very notion is illogical, nonsensical and goes against all that we know about the real world. When you observe a planet from space, all you ‘see’ is radiation. But this radiation doesn’t originate from some specific layer with some specific temperature. It comes from the planetary system as a whole. It is a total, a final, a cumulative emission flux of energy, energy radiated out all the way from the surface to the ToA. At all times. The Earth may look as if it only has one surface. In reality, in radiative terms, it has a million, a billion surfaces, all emitting radiation to space. At all kinds of strange temperatures.
The heavier the atmosphere, the higher up would be the physical temperature that would coincide with the estimated BB emission temp to space of a planet. Because the heavier the atmosphere, the warmer the surface (given equal energy input from the star). (It also naturally depends on the specific planetary lapse rate.)
So with Venus, that layer would be at a temperature of -89C (184K). Such temperatures you would find nearly at tropopause level, above cirka 80% of the total mass of the atmosphere. On Earth, the temperature would be -18C (255K) at around 5 km up in the troposphere, above cirka 50% of the total mass of the atmosphere. On Mars, however, the estimated BB emission temperature would be -63C (210K). And you cannot find such an average temperature in its atmosphere at all. It is simply too cold. So any ‘effective radiating level’ (ERL) on Mars would be, based on the many real-time surface measurements made at different locations around the planet, and also based on satelitte measurements, either on the actual ground or, more likely, below it! Below 100% (and ‘more’) of the atmospheric mass! And that’s even with a 95% CO2 atmosphere! So all that CO2 does NOTHING to lift the ERL off the ground. It seemingly rather lowers it. Go figure …
-Kristian says:
December 26, 2013 at 12:08 pm
Konrad says, December 25, 2013 at 5:27 pm:
““For a gas column in a gravity field, the relative height of energy entry and exit from the column is critical to determining the average temperature of the gas column.” – K.
(note – it has taken “Trick” over a year to concede that the above statement was true, which should give some indication of it’s importance.)”
I can see why. Because it isn’t true. This is just the ever perpetuated nonsense about the ‘effective radiating level’.-
I suppose what means is a kg of air, has more energy higher in atmosphere.
So with lapse of 6.5 C per 1000 meters. A kg of air at 20 C at 0 elevation
at 2000 meter elevation a kg of air at 7 C has same energy.
If cool to 7 C air by 2 C is same cooling 20 C air at 0 elevation by 2 C.
Or 5 C at 2000 meter same energy as 18 C at 2000 meters.
Now if cool the 2000 meter air by 2 C, it drops 307.69 meters.
Whereas one could have the 18 C air at surface be able to drop or “regain
or replace it’s energy”.
And I would say this assuming significant heat is radiate in atmosphere or surface doesn’t
cool quickier than atmosphere.
[[I do think atmosphere can radiate significant amount of energy, I just don’t think any kind of gases are radiating much energy. I think H20 gases are condensing, which has a lot latent heat involved and particles and droplets radiate a significant amount of heat. A gas like CO2 are re-radiating IR, it can absorb from surface radiating and other CO2 molecules re-radiating or from H20 gas re-radiating or droplets radiating. Only surface or particles are cooling rather than merely re-radiating and these can can warmed by kinetic energy of gases being converted into heat energy]]
-Why would there be a direct connection between the total radiative flux that a planet emits to space and the physical temperature of some specific layer within that planet’s atmosphere? The final amount of energy being shed to space by a planet over a certain period of time simply needs to match the amount of energy that same planet absorbs from its star within an equal period of time. The actual temperature of the planet or any layer within it is inconsequential to this amount.-
I think I agree. Or to paraphrase or corrupt a movie quote, does it matter it cools, next day it just warms back up again.
-Try to work out the ‘average temperatures’ of the gas columns (in effect, the tropospheres) of Venus and Mars and compare these to the planets’ estimated BB emission fluxes to space. There is no connection.-
Hmm. I would it matter in terms of how long it takes for the night to cool it.
Willis Eschenbach says:
December 26, 2013 at 3:07 am
——————————————
So clearly I can’t put you in the “yes” column. Yet.
I would agree that some equator to pole circulation would exist for a non-radiative atmosphere, however this would be far more limited due to surface friction than the tropospheric convection cells that would occur with radiative cooling at altitude. The second issue with this proposed flow is that the surface is far better at conductively heating a moving gas atmosphere than it is at conductively cooling it. (it is notable that the simply physics behind this, while known to meteorology, is not included in most AGW calculations). The surface temperature differential would not be directly reflected in the temperature of a non-radiative atmosphere.
The main issue here is the speed of vertical circulation across the atmospheric pressure gradient compared to the speed of gas conduction. At present it is fast enough to over come gas conduction and pneumatically produce the observed lapse rate. Slow the vertical circulation down to speeds that would result from the limited pole wise flows you mention and the lapse rate will weaken and the bulk of the atmosphere would trend to isothermal.
I would urge you to read Dr. Spencer’s 2009 comments on the importance of radiative gases in convective circulation –
http://www.drroyspencer.com/2009/12/what-if-there-was-no-greenhouse-effect/
Dr. Spencer indicates a largely isothermal atmosphere with only a very thin near surface layer experiencing advection winds at dawn and dusk and shallow convective circulation.
I maintain that Dr. Spencer has two critical errors in his analysis.
But first, ignoring those errors, if Dr. Spencer was right and the bulk of a non-radiative atmosphere trended isothermal with it’s temperature set by surface Tav, then that would mean that the bulk of the atmosphere would already be at a far higher temperature than a radiative atmosphere, even taking into account the claimed reduction in surface Tav under a non-radiative atmosphere.
However there are two errors in Dr. Spencer’s analysis, both in the same place – “surface Tav”.
The first is that surface Tav would not be as low as claimed under a non radiative atmosphere. DWLWIR from the atmosphere does slow the cooling of the land exactly as claimed, however it has negligible effect over water that is free to evaporatively cool. The “basic physics” of the “settled science” treat the land and ocean as just “surface” with absorption calculated on emissivity. This works fine for most materials, however the gas liquid interface at the surface of liquid water is a special condition. The empirical experiment to demonstrate this is simple to build and run.
The second error is in even using surface Tav to set the resultant isothermal temperature of a non-radiative atmosphere. For a moving gas atmosphere the isothermal temperature would instead be driven by surface Tmax. Again the empirical experiment for this is simple to build and run.
Look again at the “basic physics” of the “settled science”, it’s just two shell radiative models. There is no acknowledgement that radiative gases play a critical role in tropospheric convective circulation. The speed of non-radiative transport and lapse rate are assumed and parametrised. They should have been simultaneously adjusted for varying concentrations of radiative gases. The effect of incident LWIR at the surface should have been empirically verified. While a lot of post 1990 band-aids have been applied, AGW remains a failed hypothesis.
gbaikie says:
December 26, 2013 at 8:21 pm
————————————————————-
“I can see why. Because it isn’t true. This is just the ever perpetuated nonsense about the ‘effective radiating level’.”
Nope, you are nowhere close 😉
The method of energy entry and exit has nothing to do with it. Not a radiation problem. This is the physics of fluid conduction and fluid dynamics. Totally ignored of course in the “basic physics” of the “settled science”.
BTW, I am one of those sceptics on record as claiming that the ERL argument is tripe because the gases in our atmosphere move. In fact I have stated as much on this very thread.
To elaborate a bit, that will steadily thin the atmosphere, and cool and condense the top layer enough to sink it, producing circulation.
Konrad says, December 26, 2013 at 8:50 pm:
“Nope, you are nowhere close 😉
The method of energy entry and exit has nothing to do with it. Not a radiation problem. This is the physics of fluid conduction and fluid dynamics. Totally ignored of course in the “basic physics” of the “settled science”.
BTW, I am one of those sceptics on record as claiming that the ERL argument is tripe because the gases in our atmosphere move. In fact I have stated as much on this very thread.”
OK, fair enough. I might have misinterpreted what you were actually trying to convey there. My apologies. And believe me, I know full well that you are one of the few around who actually think that CO2 is incapable of warming the Earth system. I’m another one. You put forward some very sane arguments about the moving atmosphere which I (almost) fully agree with (not so sure about the atmosphere going isothermal without so-called GHGs, after all).
But, and to me this is a big ‘but’, you still seem to be on the ‘downwelling radiation from the atmosphere makes the surface warmer’ bandwagon. It would be very fruitful, I think, if we could all once and for all just drop that silly nonsense and move on to what’s really going on.
You do not slow the cooling of an emitting surface by feeding it with more incoming energy. That’s an absurd idea. You slow the cooling of an emitting surface by making it emit less energy going out. And you do that by making the temperature gradient away from the emitting surface less steep.
If you feed a surface with more energy and this positive transfer ends up making the surface warmer than what it was before the transfer, well, then you’ve transferred HEAT. The internal energy of that surface has increased. That’s the definition of a heat transfer. And you cannot transfer heat from a cooler atmosphere to a warmer surface.
Think temperature gradients. That’s what matters.
Stephen Wilde says:
December 26, 2013 at 2:16 am
Stephen, please quote my words that you disagree with. You know, my words that make you you claim I said “assert otherwise”. I can defend my own words. I cannot defend your vague fantasies about something you think I said.
As far as I know, I’ve never ever said that energy that is radiated is also available for evaporation. As you point out, that’s not possible.
So if you think I have said that, then QUOTE MY WORDS. I’m tired of your vague, unsubstantiated accusations accusing me of things that I never have said. When you don’t quote what I said, you leave us all in the dark. I don’t know what the heck you’re talking about, and neither does anyone else.
Thanks,
w.
Noted Willis but it’s not always easy to find specific quotes in a long thread or across multiple threads so paraphrasing is a useful time saver and it is always open to you to correct any misapprehension by restating your case rather than simply complaining about being misquoted.
I think it is implied in your previous words that all of the heat (temperature) at a surface is utilised in radiation to space and that there is no deduction for conduction.
If that interpretation of your words is wrong please could you set out a formulation that you do accept.
Even joeldshore accepted that energy used for conduction had to be deducted from the energy available for radiation to space.
On the face of it one can have a higher surface temperature than S-B if part of the surface temperature is diverted to a conductive exchange rather than radiation.
I think your previous answer was that energy coming back from the air via conduction is equal to energy leaving from surface to air via conduction so the two cancel out leaving the full radiative package still available for radiation to space.
My answer would be that although the conduction from air to surface is immediately taken away via conduction from surface to air it still increases surface temperature and is still locked into the conductive exchange and not available for radiation to space.
It’s basic accounting principles really.
In fact, if one acknowledges the increasing temperature of descending air (50% of the entire atmosphere is descending at any given time) and its ability to keep the surface warm then one no longer needs DWIR at all and the error in the global energy budget that the concept of DWIR was supposed to rectify just goes away.
Every global energy budget I have ever seen completely omits the warming of descending air and the consequent effect on surface temperature.
Everyone has been treating convection as a one way route for outgoing energy.
It isn’t.
Convective overturning takes heat up and brings heat down in equal amounts and that is what makes surfaces beneath atmospheres warmer than S-B.
And it is a mechanical process related to the amount of mass and the strength of the gravitational field.
IR is simply a by product of mechanical processes involving mass interfering with the direct transmission of solar shortwave and altering the wavelength in the process because it creates a delay in the rate of energy transmission.
That is the true greenhouse effect.
Many of your contributions here show that you nearly understand all that.
The only way your thermostat can work is for the mechanical processes to be variable in scale and speed in order to offset variations in the radiative throughput caused by internal system forcing elements such as changes in the amount of GHGs thereby keeping the system stable.
I can be more specific about the fundamental flaw in all the radiative energy budgets.
As they stand, all the budgets show radiation in equalling radiation out and that is fine at equilibrium but it misses out the thermal effect on the surface of the continuing zero sum conductive exchange between surface and air and air and surface.
That is important because as I point out above that energy locked into that zero sum ongoing conductive energy exchange warms the surface and yet the energy locked into that exchange is not available for radiation out.
That mechanical energy exchange was created from the moment the atmosphere first lifted off the ground, has remained there ever since and will remain there as long as there is a gaseous atmosphere warmed by radiation from outside the system.
Obviously the discrepancy was noted and the concept of DWIR was created to deal with it but that was a fundamental error because it constitutes double counting once one adds back in the effect on surface temperature of the ongoing conductive exchange.
The result is that the radiative theory of climate is in breach of the law of conservation of energy because it has failed to account for a mechanical energy exchange which is capable of adding to surface temperature without changing radiation in or radiation out.
Stephen Wilde says, December 27, 2013 at 12:49 am:
“Convective overturning takes heat up and brings heat down in equal amounts and that is what makes surfaces beneath atmospheres warmer than S-B.”
Mmm, this I cannot agree with, Stephen. The atmosphere is just as physically precluded from transferring energy down as heat against a temperature gradient (that is, from cooler to warmer) conductively/convectively as it is precluded from doing so radiatively.
Konrad says:
December 26, 2013 at 8:40 pm
Mmmm … yes, initially the equator to pole circulation would be lower. But there are two things that would increase the equatorial SAT.
The first is the very slowness of the equator to pole circulation. If that circulation slows, then two things will happen—the tropics will warm and the poles will cool. And of course, this will increase the equator to pole circulation.
The second thing to increase the equatorial SAT is that we wouldn’t have evaporation. Globally, this loss is about 80 W/m2. However, in the tropics at the high temperature end of the swings, evaporation is much, much higher, at least double. So we have to add in perhaps 150 W/m2 to the surface temperature at the equator.
The combination of these two will greatly increase the tropics-to-poles temperature differential … and that will make the thermal circulation all that much stronger.
This equator-to-pole circulation will be add to by the solar terminator wind. Remember that at the poles, the terminator wind always blows towards the tropics.
Net result? I suspect that we would see a reasonable amount of equator-to-pole circulation, and it will penetrate the full depth of the troposphere. Why would it not, when the entire column of atmosphere would be heated from the bottom?
Mmm … I’ll have to think about this one. Certainly, in a situation where the atmosphere overturns during the day and stratifies at night, your statement is true.
However, the main circulation in the non-GHG atmosphere would be the relatively continuous slow but steady equator-to-poles and return circulation. And with that kind of circulation, I don’t think the difference would be anywhere near as lopsided as when there is alternate stratification
The lapse rate would indeed weaken. However, since the equator to pole difference in temperatures, both atmospheric and surface, will be even larger than at present, calling that “isothermal” stretches the word.
Thanks, I’d read that. Upon re-reading, it seems good except he underestimates the equator-to-poles difference and thus the thermal circulation.
Best regards, and I’m sorry I can’t give you a yes/no answer, but the situation is complex.
w.
Kristian, many people share that view.
One has to consider energy not heat.
Convective overturning obeys the law of conservation of energy.
A molecule at the surface has the same total energy as a molecule higher up.
All energy taken up is returned to the surface but its nature changes in the process.
As the energy in rising air gains height the kinetic variety (heat) becomes gravitational potential energy (not heat) and on the descent the opposite happens.
Meanwhile, the temperature gradient is unaffected since that is set by mass and gravity reducing density with height.
There is no energy or heat flowing anywhere in the process of convective overturning. Merely conversion to PE during uplift and reconversion to KE during descent.
It is a purely mechanical process driven by uneven surface heating creating density differentials which then lead to convective overturning within the atmosphere.
The amount of heat at the surface in excess of S-B is determined by the amount of mass (in terms of density) available to absorb conductively and the work required to lift the available mass against the gravitational field.
The S-B level rises off he solid surface according to the amount of mass and the strength of the gravitational field.
Note that I learned the basic principles at school some 50 years ago but it all seems to have disappeared from the climate textbooks.
Stephen Wilde says:
December 27, 2013 at 12:49 am
Oooh, so it’s too hard to do your homework and provide quotes when you attack someones ideas? You poor guy, that must be tough …
You want me to “correct any misapprehension”? Fine. Here it is, clear as I can make it.
Man up and provide the quotes to back up your claims, and quit your half-baked misrepresentations and fantasies about my ideas. Your misapprehension is that your slipshod work and inattention to detail is somehow acceptable, and that it is up to me to correct you. That is your job, not mine.
I hope that clears up the misapprehension. Quote my words if you disagree with them. It’s not just for me. It’s so that everyone can understand what you are talking about. And no, Steven, I can’t clear that up or “correct your misapprehensions” because I DON’T HAVE A FREAKING CLUE WHAT YOU ARE ON ABOUT!
That’s why I need you to provide the context—because no one can provide it but you.
w.
Actually, Willis it isn’t much use providing your past quotes because anyone’s quotes can be interpreted multiple ways.
Much better to try and reach understanding by paraphrasing each other during a mutually respectful exchange in order to tease out differences in approach or means of expression.
If my paraphrasing of what you have previously said or implied in multiple past comments is wrong then it is for you to clarify what you really think.
I often find myself having to repeat or reformulate because people have misunderstood some aspect of things that I have said and you should expect to have to do the same.
I am at a loss as to why you think I have launched any sort of ‘attack’.
I have always been very supportive of your thermostat hypothesis and merely sought to make it more comprehensive, fit it into a wider global scenario and refine a description of some of the mechanisms that must underpin it.
I agree entirely but there are logical constructs used in science that have no physical existance but are useful concepts or “handles” on a problem to facilitate discussion or calculations.
The concept of a “point mass” or a “point in geometry” are two examples. Neither exist in reality, ie I can’t put either of them in display case and show them off, but they greatly simplify discussions and calculations.
The effective radiation surface is the same sort of concept. Instead of going into a pages long discussion of how a million billion layers in the atmosphere radiate, we can usefully say that “as a limit” they approximate a single surface at some definable temperature which we call the Effective Radiation surface. For another example radioactive half life, is another useful approximation. Statistically 50% of a radioactive material undergoes decay in a certain period of time, and for practical purposes we can say the radioactive material is gone after 7 half lives have expired, since after 7 half lives only 0.7% of the original radioactive emissions remain.
I am not trying to communicate with you, since you already understand the concept, I am trying to build a logical construct that is intuitively obvious (or at least understandable and worth consideration) for those who are currently stuck in the classic green house gas world view and dismiss the idea of conservation of energy and potential energy gradients being the better explanation of surface warming of a planet with an atmosphere. All you need to explain the entire temperature profile in the atmospheric column under the pressure modulated heating construct is to define one point in the atmospheric column which has a defined and unique temperature. Then potential energy calculations allow the temperature and pressure at all other levels of the atmosphere to be calculated.
I realized last night that there might be a better “set point” rather than the ERL which concerns you so much. That would be the approximate equality of the temperature at the top of the atmosphere to the temperature of deep space.
Going back to our logical construct of an isothermal column of gas inside a super insulating silo, extending from the surface to what ever we define as the top of the atmosphere. Simple potential energy calculations define what its gravitational potential energy would be at all altitudes in the silo, and all pressure levels in the silo. Then you remove the super insulating top and bottom cover of the silo and allow heat flow to occur. The bottom of the silo would be at some temperature Xp the surface temperature of the planet. The top would over time equalize to approximate the radiant temperature of deep space 2.7 k or Xds.
Once you fix the top of the column at approximately 3 K, the ideal gas laws define the entire temperature profile all the way to the bottom based on conservation of energy laws and the rules of adiabatic heating and PV=nRT
I think that is a more useful and perhaps more easily understandable way of looking at the problem then some construct like the ERL.
Then under Occam’s razor, this becomes least complex explanation of planetary atmospheric temperature profiles, which is founded on only two widely accepted laws, conservation of energy, and the ideal gas law. Radiation physics become irrelevant as they only describe the method used to reach the limit defined by these two laws, but they are not the cause of the temperature profile.
Minor addition you also need the law of gravity and the radius of the planet and the estimated atmospheric mass to define the gravitational potential energy and the pressure potential energy, along with the radiant temperature of deep space at the beginning of the calculation, so I guess it should be based on:
3 laws and 3 physical constants to define the entire pressure, temperature profile of any arbitrary planet.
Stephen Wilde says:
December 27, 2013 at 2:33 am
Gosh, that sounds like fun. Let me start the paraphrasing.
The problem is not the different interpretations of the text, Stephen.
The problem is, when you start with your “Willis said this” or “Willis claimed that” fantasies without quoting what I actually said, I DON’T HAVE A CLUE WHAT TEXT YOU ARE INTERPRETING. And as a result, I can’t defend or discuss it, respectfully or any other way.
I’m more than happy to discuss the manifold interpretations of my ideas about something.
But I can only do that if you specify exactly what I said about that thing. NOT your misinterpretation of what I said. NOT your paraphrase of what I said. NOT your faulty memory of the post last year when I said it. We can get to that, but only if we first know which text you are babbling about …
Because I’ll be damned if I’ll try to defend your exegesis on some unspecified thing that you fantasize I might have said somewhere two years ago. If you’re too lazy to look up where I might have said it or what I actually said, piss off. I’m not interested.
On the other hand, if you want to join into the scientific conversation, then I encourage you to put on your big-boy pants and start taking the trouble to find out what I actually did say on a given subject.
Then, after you’ve quoted what I said, you can tell me exactly where you think I went off the rails, and we can have a conversation because we have a text upon which we can comment. That way, I and everyone else get to look at my claim exactly as I made it, and your objection to that claim, exactly as you’ve specified it.
Then, we can have a discussion, because we have something to discuss, and you and I and everyone knows exactly what you and I have said about it.
Or not. Your choice,
w.
Willis, the issue at hand is very simple.
You pointed out that the surface has a temperature that under the S-B law should radiate out to space more radiation than is received from space.
Tell us all whether or not you accept that the apparent ‘surplus’ of energy at the surface could be going into the conductive exchange of energy with the atmosphere.
Stephen Wilde says:
December 27, 2013 at 10:38 am
Stephen, what part of please quote my exact words so we know WTH you’re talking about was less than clear to you? Once again, your paraphrase is useless. Where did I say whatever has you so exercised, and exactly what did I say?
Sheesh … you’d think a simple request to quote my words would suffice …
w.
Kristian 12:47pm: …go to a planet where we do not already know the surface temperature, only its solar input and the content of radiatively active gases in its atmosphere. Then work out its surface temperature from this. This should work for all planets with such an atmosphere, shouldn’t it?”
Yes Kristian. The construct already has been applied successfully to a planet where the surface temperature was unknown. Venus. The Soviet Venera program built the 1st thermometer in the early ’60s with a T range up to the low 700Ks using this basic science then they went to the planet and confirmed in situ.
The construct will work just as well for exoplanets once the eqn.’s inputs are reasonably known.
“I said ‘solar input’. That’s after albedo.”
Now we get a definition. Fine.
Use solar irradiance after albedo & mass of atm. which should be good enough to compute global surface Tmean since your hypothesis is these alone set surface temperature.