This is one of those scratch-your-head moments when a skeptic just has to ask “Could the modelers really have overlooked that?” Given the $79 billion odd dollars in research and the billions of dollars bet on the models, it seems hard to believe. Then again, the same team didn’t ask any hard questions when one study overturned hundreds of other studies that showed it was warmer 1000 years ago, they are the people who think it’s ok to hide declines, hide data and dodge FOI’s. This is, after all, the Team who call fertilizer — “pollution“. Maybe a couple of extra Watts per square meter could have slipped by?
When a greenhouse gas absorbs infra red, its molecules emit in a random direction — so half of its emissions are emitted up, towards space. This is kind of the key to the matter.
George is an electrical engineer, and since I’m married to one I know that EE’s are used to dealing with complex feedback loops in systems. George uses the points we know — incoming solar radiation, outgoing radiation, the Stefan-Boltzman equation — and shows in a simple and logical fashion that the numbers all balance.
But once we have this un-obfuscated picture of radiation flows from George, we can see the potential for some double-counting going on in a crucial climate calculation.
Everybody who’s anybody in the climate calculations knows that if CO2 doubles, the IPCC reckons that it is supposed to be equivalent to adding 3.7 W per square meter of net extra incoming solar energy (which means “heat”) to Earth’s big budget. Of course, adding extra CO2 to the atmosphere really just reduces the amount of radiation out to space. The flow from the sun is not increased; the 3.7 W/m-2 increase in forcing is solely due to less radiation leaving the earth.
The 3.7 W/m-2 is calculated from line-by-line spectral calculations, but does it correctly include changes to both the 93 W/m^2 going straight through the transparent window to space and the 146 W/m^2 absorbed by the atmosphere and then escaping to space?
The 1.2C no-feedbacks temperature increase from CO2 doubling is calculated by applying Stefan-Boltzman to the top of the atmosphere, where it is 255K: a surface around 255K has to warm by 1.2C if it is to emit the extra 3.7 W/m-2 required to keep the earth in radiative equilibrium when the CO2 doubles. We apply this at the top of the atmosphere because we can — we know the fluxes there and all the heat flow is by radiation. But we really want to know the change in temperature at the surface — a very different, and messier, situation. Obviously the radiative flows at the surface are only changed by about half as much due to a CO2 doubling, so presumably only about half the full 3.7 W/m-2 applies to change the surface temperature.
Like Judith Curry (see her blog, Part I and Part II), we think the calculation of a 1.2C warming for CO2 doubling is opaque and uncertain, and open to challenge. On the face of it, it may well be half that, around 0.6C. (And it’s not like those who aim to alarm us, ever exaggerate or hide behind obscure and unexplained data or calculations, is it?)
The flow-on effects of this would run rampant through the scenarios and projections. Instead of causing 1.2 degrees C of direct warming (as per Hansen et al 1984), doubling CO2 would only lead to 0.6 C, and all the feedbacks apply to that. So the “average 3 or 4 degree” estimate for the mass of climate models comes back to 1.5 – 2 degrees, and the skeptical view, which points at empirical evidence for negative feedbacks (Lindzen and Spencer) would roughly halve the 0.6C which makes 0.3C, and that converges nicely with the Miskolczi estimate of around 0.24 C.
Guest Post by George White
Evolution of an Energy Budget
There’s 341.5 W/m2 of average incident solar power and the average albedo is 0.3, so 239 W/m2 arrives at the surface and 102.5 W/m2 is reflected into space. Any solar power absorbed by the atmosphere will have half directed back into space and which is considered as incremental reflection and included in the albedo. That returned to the surface is included in the 239 W/m2 . Both the solar constant and the albedo are measured and uncontroversial.
The average temperature of the Earth’s surface, and accordingly it’s thermal mass, is 287K. Stefan-Boltzmann dictates that the thermal mass must be emitting 385 W/m2 from it’s surface. This radiated power is a consequence of the temperature of the thermal mass and nothing else.
Some of the surface power passes through the transparent window in the atmosphere. From HITRAN based, line by line, 3-d atmospheric simulations, the average direct transparency is about 24.1%, meaning that 93 W/m2 of the surface power passes through the transparent window and out into space and the rest is absorbed by the atmosphere.
For calculating the effects of clouds on the net transmittivity, T, clouds are considered as act as dynamic ‘plugs’ that reduce the amount of surface power that leaves the planet. Thus emitted cloud power is considered to be obstructed surface power in the present, even though the actual joules of emitted power originated from the surface, or possibly the Sun, in the past. All of the values that went in to computing T are measured values.
Now examine the top of the atmosphere and consider the Conservation of Energy constraint that the power leaving must be equal to the power arriving. This requires that the atmosphere radiate 146 W/m2 to maintain balance.
Now, subtract the power leaving the atmosphere from the power entering to determine how much power is being returned to the surface. This is 146 W/m2 , the same amount that is leaving the top, making the fraction of power up to power down equal to 50%.
If we now examine the radiative balance at the boundary between the surface and atmosphere, it’s already balanced! At this point, we haven’t included any sources of non radiative power to the equation. However, all of these will be between the surface and atmosphere and have no impact on the fluxes at the top of the atmosphere. Since we are already balanced, any non radiative power entering the atmosphere from the surface must be returned to the surface.
This shows how to obfuscate this view of the radiative balance to look like Trenberth’s.
First, take 78 W/m2 of the solar power incident to the surface, absorb this by the atmosphere and return this as ‘back radiation’.
Next, add 97 W/m2 of latent heat and thermals from the surface to the atmosphere and then return this as ‘back radiation’.
When you add these return paths, we get 321 W/m2 of ‘back radiation’, which is close to Trenberth’s value of 333 W/m2 , although he also uses a slightly higher surface temperature and a smaller atmospheric window.
The key point to notice is that the non radiative components of the Trenberth energy budget are irrelevant to the radiative balance. Whatever is added to the atmosphere must be returned to the surface in equal and opposite amounts.
This particular picture would be exact if the planet had no water and all atmospheric absorption was by GHG agents that absorb only LW IR. Adding water to the equation doesn’t change the balance, but does set up additional circulation currents between the water in the oceans and the water in the atmosphere. This is often confused as being fundamental to the balance, when it’s not.
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We’ll be posting more follow up on this topic from George soon.
To understand what is wrong with the odd $79 millions, read Slaying the Sky Dragon; Death to the Greenhouse Gas Theory and my blog.
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“Obviously the radiative flows at the surface are only changed by about half as much due to a CO2 doubling.”
If 3.7 W/m^2 less are leaving the atmosphere than coming in, and sunlight (as visible light, not absorbed by greenhouse gases) primarily warms the Earth, then the 3.7 W/m^2 imbalance can only be mitigated by an increase in ground temperature that emits an extra 3.7 W/m^2.
I’ve seen this “halving” stated on a number of blogs, mostly sourced from G. White – it’s quite simply incorrect. G. White has been told that repeatedly, with references to the correct measurements and calculations. I’m saddened to see him continuing with these statements.
21
You’ve incorrectly assumed that back-radiation equals outgoing radiation into space.
The atmosphere has a temperature gradient so the back-radiation is much greater as it originates from a lower warmer part of the atmosphere than emission into space which originates from a higher colder part.
10
socold – Agreed. The current backradiation of 333 W/m^2 is about 85% the ground radiation of 396 – the 3.7 extra will require considerably more surface emission in the face of the backradiation. If I recall correctly we would see something like 16.8 W/m^2 extra emission from the ground to pump the extra energy out as an additional 3.7 W/m^2 at the top of the atmosphere.
11
Dr. Roy Spencer has an excellent illustration of the differences between ground level and top of atmosphere IR on his blog – Yes, Virginia, Cooler Objects Can Make Warmer Objects Even Warmer Still; the fourth figure. I’ve tried to include in my post, although I don’t know if it’s coming through – the preview doesn’t show it.
10
KR,
The three laws of thermodynamics prohibits the so called AGW radiative forcing by CO2 et.al. that is colder than the surface.
A stupid simple thought experiment demonstrates the above fact.
1. Any energy coming from the surface absorbed by CO2 et.al. comes FROM the surface and is no longer there to elevate surface temperature and thus the surface becomes colder.
2. Any energy that passes from the CO2 et.al. to the earth is no longer in the CO2 et.al. to increase it’s temperature and thus the CO2 et.al. becomes colder.
3. Any energy transaction between the surface and CO2 et.al. is at best a zero sum game.
Thus there can be no radiative forcing and no AGW from radiative forcing by CO2 et.al.
A equally stupid simple physical experiment demonstrates the above fact.
1. Illuminate a surface with a bright light.
2. Arrange a mirror so that it reflects the light reflected from the lit surface without
also reflecting the light from the bright line back to the lighted surface.
3. Notice that the light reflected from the mirror does NOT make the lighted surface any brighter.
4. Arrange the reflection so that the mirror reflects the light from the lighted surface to an unlighted surface
5. Notice that the unlighted surface is made brighter by the reflected light.
The lighted surface is “hot” while the unlighted surface is “cold”. The light from the “hot” surface does not heat the “hot” surface but heats the “cold” surface.
That CO2 or another colder body is involved with the energy transaction does not change the fundamental thermodynamics of the situation. The surface does not and cannot “know” were the energy came from when it receives it nor where it is going when it emits it.
The entire edifice of the AGW fantasy rests upon violating the three laws of thermodynamics. Can’t be done. No way, no how, and no when! You can’t transfer energy and still have the energy you transferred at its source. You can’t use the energy and still have it to use again. All you can do is transfer or transform the energy. If you extract any useful work out of that transfer or transformation, the quality of the energy is degraded and an increasingly smaller fraction is available to do useful work. This is an inescapable fact of reality. Any Science Fiction that says otherwise will remain forever fiction.
It is irrelevant that there are isolated verifiable factoids within the construct known as AGW. If the fundamental premise fails, the entire construct falls.
I suggest you need to go back to school to learn some basic logic and physics rather than believing the failed pseudo science from the climate science fiction writers.
20
@KR: As far as i know, Hansen and Schmidt have “observed” the radiative imabalance with – you guessed it – a model run (and thus sent Trenberth on a desparate search for the “missing heat”). More precisely, they did an intelligently fudged paper that mixes satellite observations with model runs to make it look like science.
http://news.bbc.co.uk/2/hi/science/nature/4495463.stm
So whether there actually is an imbalance can very much be doubted. ARGO surely doesn’t find the missing heat. The names Hansen and Schmidt on this study put it deeply into the realm of bogus science; as they are responsible for GISTEMP.
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KR,
For 3.7 W/m^2 of incremental absorption to occur, T decreases from 0.241 to 0.232. At the current surface temperature, 89 W/m^2 would pass through the window, while 296 W/m^2 is absorbed by the atmosphere and 102.5 W/m^2 is reflected. Half of 296 W/m^2 is 148 W/m^2, so the net power into space, at the current surface temperature, is 102.5 + 89 + 148 = 339.5 W/m^2, requiring an incremental 2 W/m^2 of power at the top of the atmosphere, while the power sent to the surface becomes 239 + 148 = 387 W/m^2, which is 2 W/m^2 more. Now, the surface must emit 2 W/m^2 more in order to be in balance.
For a surface emitting 387 W/m^2, 89.8 W/m^2 passes through the window, while 297.2 W/m^2 is absorbed by the atmosphere. Half of 297.2 is 148.6 W/m^2, so the net power leaving the planet becomes 102.5 + 89.8 + 148.6 = 340.9 Wm/^2, which is 0.6 W/m^2 too little. If the surface power increased by 3.7 W/m^2, the power leaving the planet becomes 102.5 + 90.2 + 149.3 = 342.0 W/m^2, which is 0.5 W/m^2 too much. The actual amount that the surface power must increase is given by (A/2)*g, where A is the incremental absorption and g is the surface gain, defined as the emitted surface power divided by the incident surface power, g = 385/236 = 1.61. For 3.7 W/m^2 of incremental absorption, the incremental surface power is 3.0 W/m^2. Now, the power leaving the planet is 102.5 + 90 + 149 = 341.5 W/m^2, while the power entering the surface is 239 + 149 = 388 W/m^2. Both of these are exactly as required.
So yes, relative to the incremental surface power required for a new equilibrium, it’s more than half, but it’s also less than 1. The bottom line is that only half of the incremental absorption affects the surface temperature and that this power is ‘amplified’ by the same factor applied to the incident solar power. This amplification factor of 1.6 reflects the net system feedback, whose effect influences only 1/2 of the incremental absorption.
George
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KR,
Dr. Roy Spencer’s example is not an example of radiative forcing from a colder body to a warmer body. It is a discussion of a system that contains a body that has a continuous source of heat, a colder body that does not, AND an enclosure that limits the rate of transfer of energy out of the system.
The temperatures of the various bodies will be determine by the rates of energy transfer and how long they remain constrained by the system boundary. The cold bar will get warmer until it is radiatively invisible to the hot bar. While that warming is occurring, the hot bar is fractionally colder because there is a sink of heat near by. Once done, the hot bar returns to its original temperature and the system is in a state indifferent from before the introduction of the cold bar.
The exact same logic applies to the blanket you use on a cold night. The blanket does not heat you. YOU heat the blanket until the energy transfers are once again in equilibrium. The blanket merely reduces the rate of energy transfer from your body to the environment. It does not and cannot warm you because you are the only source of energy in the system. Putting a cold bottle of water with you under the blanket (a situation exactly analogous to his first system) does not make you warmer. It makes you colder until the bottle warms to equilibrium temperature. Then, the fact that it is there means nothing to the state of the system in equilibrium.
Dr. Spencer wrote some science fiction that included pretty pictures but it’s still fiction when applied to the fundamental premise of AGW. He is apparently trying to dazzle his audience with bullshit rather than being honest about what he is doing.
Again, if you believe Dr. Spencer’s conclusions in his article, I suggest you go back to school and learn some basic logic and physics. The level of logic and physics needed for the above analysis is only microscopically above that required to pass high school of 60 to 100 years ago. Today, apparently, you need more than a PhD to achieve that level of skill and knowledge.
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Lionell Griffith – I suggest you take a look at Roy Spencer’s piece, which I referred to in #4. Spencer is quite the global warming skeptic, and I think he’s explained matters quite well. The “2nd law of thermodynamics” objection doesn’t hold water.
If you want real fun, go look up the subject of “2nd law of thermodynamcs” on Science of Doom…
DirkH – The 3.7 W/m^2 number comes from Myhre et al 1998, which actually reduced the estimated CO2 forcing about 18% from those used in the older, 1995 IPCC calculations (better computations of inclusive atmospheric effects). That’s the number from the physics for doubling CO2 (which we haven’t done yet), not TOA measurements. If you disagree with how Myhre calculated that, well, you can always submit a comment to Geophysical Research Letters and let them know what he did wrong 🙂
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I’ll let those links stand for themselves.
11
socold,
As I’ve explained, the concept of back radiation misrepresents the actual system. For example, thermals are part of an atmospheric circulation current with a Z component. To the extent that hot air rises, cold air is sinking somewhere to fill the vacuum left as the warm air rises. Relative to latent heat, this should be considered to stay with the water. While joules are removed from the surface as the water is evaporated, the same amount of joules must be added back to the water as it condenses to fall as rain. Trenberth’s ‘back radiation’ includes power returned to the surfaced as the return path of thermals and as the return path of rain.
10
@Lionell Griffith:
Lionell, is is conceivable that a change in the system leads to a change in the energy distribution. Such a change would occur until a new equilibrium is reached. The AGW conjecture states practically that the currently rising CO2 concentrations constitute such a change.
Imagine a white piece of paper on which the light from your lamp shines and gets reflected. Only a tiny bit of light is absorbed, the paper stays cool. Now start painting the piece of paper black. The more you paint it black, the higher the average surface temperature of the paper rises.
The new equilibrium is reached after the piece of paper is all black, has heated up, and now emits more blackbody radiation. So, less reflection, more absorption and re-emission; but in both cases, radiative balance. The temperature of the paper is higher after painting it black.
10
George aka co2isnotevil – You went around on that in a ~450 post hijacked thread over on Skeptical Science; your “halving” is incorrect, your atmospheric window of 93 is incorrect (should be 40) along with other numbers, and your 1.6 “gain” is a varying result, not a constant. I’m not going to re-debate that here.
Enjoy yourself.
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@KR
“DirkH – The 3.7 W/m^2 number comes from Myhre et al 1998, ”
I was not questioning the 3.7 W/m^2 but to you saying
“If 3.7 W/m^2 less are leaving the atmosphere than coming in…”
So – whether this is the case – that there actually is a radiative imbalance on the Earth today – is IMHO still in question. But thanks for pointing to the source of the 3.7 W/m^2 number.
10
@KR:
And saying “but it must be so because CO2 is rising” will not help you, nor “A GCM has proved it”. I will accept measurement data. Yeah, i know, doesn’t exist. So the question is still open.
10
DirkH – The CO2 absorption of IR can be demonstrated in a high school lab; the Myhre computations take those basic observed physics and integrate them across the depth of the atmosphere.
You’re quite right, by the way – we haven’t had a 3.7 W/m^2 forcing from CO2, as CO2 hasn’t doubled. It’s gone from 280 in 1850 to 390 or so now, which should be a TOA forcing of:
F (W/m^2) = 5.35 ln (CO2 / CO2 [starting]) = 1.77 W/m^2
if Myhre is correct.
11
Lionell Griffith:
January 13th, 2011 at 6:10 am
Just did your experiment.
At step 3 the light reflected from the mirror does make the lighted surface brighter( No light was allowed to be reflected from the source which was a ceiling down light). The lighted surface was a gyprock wall. The mirror held by hand close to the wall and the bright spot was obvious to the naked eye. Do this yourself!
However the world is not flat as in the above diagram, so any heat radiated from atmospheric CO2 in the horizontal direction will go over the horizon and out. Any heat radiated in a slightly downward direction will also go over the horizon and out. So less than half the downward radiation makes it back to the surface. This effect increases with altitude. CO2 therefore acts as a cooling antenna radiating heat out into space thus negating much of any trapping effect..
10
KR,
No. Trenberth’s atmospheric window includes 40 W/m^2 coming from the surface and 30 W/m^2 coming from the clouds for a total of 70 W/m^2. However, these values are not justified in his paper and seem to be ‘guesses’. In any event, his window is 70/388 = 0.18, which isn’t that much smaller than mine of 0.241. Now, if the window was as small as Trenberth claims, more than half of the power absorbed by the atmosphere must be emitted into space in order to meet the shortfall. I don’t see how a smaller atmospheric window helps your case, if anything it detracts from your assertions.
What Trentbert fails to account for is radiation from the atmosphere (not just the clouds) that passes through the transparent window. When this is added back, 93 W/m^2 is the right value.
10
KR #9,
I don’t bother to dispute the 3.7 W/m^2 number. My simulations put it at 3.6 W/m^2 using 2008 HITRAN line data, which as far as I’m concerned is close enough. But what my simulations do show is that this is the incremental decrease in power passing through the transparent window, not the net decrease in power leaving the top of the troposphere. This is the assumption that the IPCC has very wrong.
10
Ah so during the long Arctic winter night Arctic water will loose more heat to space than if the area had been covered by bright white Arctic sea ice.
10
co2isnotevil – If 3.6-3.7 W/m^2 are not going to space, whether within just the “atmospheric window” or across the full spectrum, that’s all forcing, all incremental change.
Incidentally, does your model also include the rise in effective altitude of stratospheric CO2 with concentration? Which (given the lapse rate) means that the CO2 emission to space effectively is coming from a higher and colder altitude where the mass concentration of CO2 has dropped sufficiently?
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It may be that our disagreement on the “window” numbers is a matter of definition; that’s fine. But 3.6 or 3.7 W/m^2 is the forcing on the Earth/atmosphere system. And that will result in a warming of ~1.2°C without any feedbacks (Lorius et al 1990).
11
KR, socold,
Perhaps you should explain why my numbers work out if my calculations aren’t correct. Rather than just assert that I’m wrong, you should try and explain why the math works perfectly anyway. I should also point out that these relationships hold even at the gridded level when I analyze the ISCCP weather satellite data.
10
KR, #21
Yes, my simulations fully account for atmospheric lapse rates. Relative to the 3.7 W/m^2, this is the incremental atmospheric absorption, which the IPCC calls ‘forcing’. Of course, in a strict sense, changing GHG concentrations do not force the system, but simply modify the systems response to solar forcing, which is the only influence that can actually ‘force’ the climate system. In the context of LTI theory, which is how you would quantify the climate system, forcing is the input to the system, which in this case is the Sun. It’s real clear to me that the IPCC has been redefining terms which otherwise have a strict physical significance, just to suit their agenda and to obfuscate reality.
10
One factor that many of you are missing is the fact that radiation is not the only way that heat is transferred, and that radiation absorbed by a CO2 molecule does not need to be re-emitted, and in fact most often is not. When a CO2 molecule absorbs a photon of IR, it vibrates. In the relatively dense troposphere, the CO2 is much more likely to collide with an O2 or N2 molecule, passing that vibrational energy on as translational energy, i.e. making the target of the collision (O2, N2) move faster, i.e. making it “hotter.”
The upshot of this is that with rising CO2 (or H2O levels) in the atmosphere, radiation leaving the surface is more likely to warm the atmosphere itself than to escape or re-radiate either up or down (or sideways). Of course, there are lots of paths here, and the probabilities change as the proportions of the component molecules change, as well as the density and most importantly the temperature of the atmosphere.
For example, increased CO2 in the stratosphere leads to cooling, not warming, because there it is far more likely that a CO2 molecule will become excited (gain energy) through a collision with an O2 (or O3) molecule, and then radiate the energy away as IR before it undergoes another collision. It is less likely to absorb IR and do the reverse (i.e. pass it on as heat to an O2 or O3 molecule). This sort of cooling is very obvious in the satellite measurements, and is the key fingerprint in GHG warming (not the “hotspot,” which is in fact a signature of any warming from any source).
The atmosphere thus fails to radiate out as much heat as is coming in from the sun until the surface and atmosphere together have warmed enough to balance this effect (i.e. to both let enough IR through, or to “generate” more IR through collisions between O2/N2 and CO2/H2O, since O2 and N2 do not, for all reasonable intents and purposes, themselves emit relevant amounts of energy in the IR spectrum — this is why air — primarily O2 and N2 — is such a great insulator — down coats are filled with down because it’s fluffy and leaves big pockets of air, which is the real insulation in a down jacket, while the gaps of air in a cooler or thermos are the insulators in those cases).
The point is that thought experiments which merely involve throwing IR photons back and forth, or up and down, are far too simplistic a way to look at the situation.
For example, Siliggy’s thought that IR will go sideways through a dense atmosphere and somehow escape, so some of IR emitted from the atmosphere will “go over the horizon and out,” and less than half will go back down, is overly simplistic, and incorrect. Similarly, while CO2 does cool the stratosphere, the mechanism is nothing like that described, and it does not succeed in “negating much of any trapping effect.”
Similarly, Lionel’s “stupid simple thought example” (his words, not mine) is missing a critical component, which is the energy absorbed by CO2 but then passed on as heat to O2/N2, where it will not be radiated away until the system has reached a new, higher temperature. By including only radiation in his 3 point experiment, he failed to “read between the lines,” so to speak.
His misunderstanding of the situation leads to a misapplication of the laws of thermodynamics. He is quite right when describing the use of a blanket, and yet a blanket still works. It doesn’t violate the laws of thermodynamics. Without the blanket your body loses heat. With the blanket, it loses heat at a slower rate. That’s in a cold room. If you site under a heat lamp (the sun) then you get unbearably hot, because the blanket keeps you from losing heat until you reach a temperature which is high enough to radiate out enough to balance that coming from the heat lamp.
If you put on a heavier blanket, you get even warmer. The blanket is not violating the laws of thermodynamics, and neither is the atmosphere.
The atmosphere is no different. The earth is constantly, continuously heated by the sun. The earth tries to radiate that heat away. The atmosphere acts as a blanket. Adding CO2 is like using a thicker blanket.
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co2isnotevil – “Forcing is the input to the system, which in this case is the Sun” sounds simply like a terminology issue. The generally accepted term in climate science (not just the IPCC, but every paper that I have read in the field) is that “forcing” is an imbalance between incoming and outgoing energy to the Earth, whether caused by greenhouse gases, aerosols, solar irradiance, volcanic dust, surface albedo, etc.
In the end, though, the terminology really doesn’t matter. Doubling CO2 will induce an energy imbalance (3.6-3.7 W/m^2, as you agree), and that will change the temperature of the Earth. The calculations for how much indicate 1.1 to 1.2°C for that change.
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KR@16; F (W/m^2) = 5.35 ln (CO2 / CO2 [starting]) = 1.77 W/m^2 may be theoretically correct, or not, but it certainly is not empirically correct; a 40% increase in CO2 should have produced a GAT temperature increase of ~ 1.3C; temperatures have risen over that period of CO2 increase by ~ 0.6C, less than 1/2 the result demanded by the IPPC forcing figure; and that is without deducting solar effect, which the IPPC estimates between 0.4[TAR]-0.1[AR4], or anything for natural variability, PDO, which produced a 0.3C temperature increase in 1976. Perhaps you can explain that shortfall?
10
KR,
Yes, there is a terminology issue, where climate science has kept the meaning of certain terms, for example, forcing, yet have redefined it as something different in order to make it seem scarier than it really is.
I do not agree that the 3.7 W/m^2 of incremental absorption represents an imbalance, either at the surface or at the top of the troposphere. The actual imbalance at both the surface and the top of the troposphere is about half of this amount, but in any event, this imbalance is not ‘forcing’, but a change to the systems response which dictates a different equilibrium.
Consider an electrical amplifier. The input signal is the forcing and the base/treble controls change the response of the system. The output at specific frequencies changes, but not because the input changes, but because the systems response changed. The fundamental difference between the response of the system and it’s stimulus is ignored (or unknown) to most climate scientists, yet is crucial for understanding how the climate responds to change.
10
KR,
This is incorrect. See my previous comment on the CO2 and the stratosphere.
But the overall thought is (I think — don’t press me on this, because it’s not my strong suit) mostly correct, in that emission will ultimately come from a higher altitude (although in the troposphere, not the stratosphere). I don’t know that it will be colder, though, just higher.
In fact, too, due to heating of the atmosphere the height of the tropopause should change, and in fact it has risen several hundred meters in recent decades.
10
The problem here is that all are assuming that the measured downwelling IR comes from greenhouse gases only – the model becomes problematical if the IR also comes from atmospheric electric currents operating, for the main part, in dark current plasma mode.
Then the energy input has to include the millions of amperes measured entering the earth via the polar aurora, south and north, as well as from the plasma torus (Van Allen Belts) along the equatorial region. Also electrical energy leaves the system as well, since all electrical currents explicitly mean the presence of a continuous electric cirquit. Just think of the earth as a leaky capacitor immersed in the plasma of space and that weather is the physical behaviour of the thin gas/liquid film coating it. The stratopause, thermopause, tropopause etc could also be likened to plasma double layers producing electric charge separation. These appear when there is an electric current present, and are caused by the electric currents, and not vice versa. Direct solar energy is only part of the energy the earth receives – the rest coming via the electromagnetic circuits either via the magnetic flux tubes discovered by the THEMIS mission, or from the Van Allen belts.
But ignore this energy source and only limit it to solar irradiation, then you would have the discussion here where there seems to be little or no agreement.
Most of the arguments seem to dwell on the intellectual plane and are essentially rhetorical debating points etc. Fred Hoyle noted that when this happens in a science, then it’s more likely that the protagonists are thinking with the wrong ideas, here solar radiation alone coupled with CO2 IR emittance.
The earth’s surface is extremely active in an electrical sense, and to ignore that force when trying to understand the behaviour of the medium in which this electrical force operates in, ie the earth’s atmosphere, is basically to find yourself stalled in a modelling cul-de-sac, hence the tower of Babel type of debate here.
The only problem is that the idea of a greenhouse effect exists solely because it’s needed when electrical inputs are ignored. Add the electrical connection and the only greenhouse effect needed is that of water – the rest of the thermal anomalies could be better explained in terms of electrical effects, and the IR behaviour of a trace gas irrelevant.
If the downwelling IR comes from atmospheric electric currents, then little wonder the sceptics are correct in their opposition to the CO2 effect being put by climate science.
10
cohenite,
The Earth is covered with 346,049,000,000,000,000,000 gallons of water (the oceans) which, given the high specific heat of H2O, will take a considerable amount of time to reach thermal equilibrium.
The upshot is that if GHG theory is correct (and yes, I believe it is beyond any doubt), the planet will continue to warm substantially long after we curb CO2 emissions, and any temperature anomalies or trivial effects which people today attribute to climate change are nothing in comparison to what is coming for future generations.
Any argument against GHG theory by claiming that there is no substantial warming or undeniable empirical evidence (yet) is like the guy who jumped off the top of the Empire State Building and was heard to say, each time he passed an open window, “so far, so good.”
I know this sentiment will bother most people here, and I apologize for that, but it is in fact the case. If you want to argue against GHG theory, try to do so with science and logic, not with suppositions based on what in climate-time amounts to very short term observations.
10
cohenite – What’s I’ve seen described is that the 0.6°C change observed is only _part_ of the response to direct forcing and (whatever the climate sensitivity) feedback; the oceans are heating, ice caps are melting, glaciers retreating from CO2 already in the system, and it’s going to take some time for the Earth to reach equilibrium with where we are right now – even if we locked CO2 levels at 390 tomorrow.
And no, I’m not going to argue those points with anyone – the data on glaciers, ice caps, and ocean heat are readily available.
10
Louis,
Yes, electrical forces are important, but not as much relative to the energy balance. A lightning bolt is about 1 GJ and there are about 100 per second, worldwide (including lightning to the ionosphere). If we consider this as the leakage offsetting the incident electrical power, it’s about 1E12 joules/second. The total solar input is on the order of 2E17 joules/second, so the net electrical flux is only a small fraction of the total incident power flux.
10
KR,
If as you suggest, it requires over 16 W/m^2 of incremental surface power to offset 3.7 W/m^2 of forcing, calculate the albedo change (the primary ‘feedback influence’) required for this to occur and explain how the feedback causes this much change to the albedo. You might also explain why it doesn’t require (16/3.7)*239 = 1034 W/m^2 of surface power to offset the 239 W/m^2 of incident solar power.
10
KR, fair dinkum, you know very well you are describing the difference between transient climate sensitivity [TCS] and equilibrium climate sensitivity [ECS]; this difference is described at AR4:
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-5-2.html
The problem with the difference between TCS and ECS, which AGW depends on to explain the shortfall between its forcing formula and the lack of a consistent GAT response, is that there is nowhere for that “missing heat” to be stored; its not in the ocean and its not in a THS; and as Beenstock has shown CO2 only heats when it is increasing exponentially to to the logarithmic decline in heating effect; when it is increasing linearly or not at all it has no heating effect; combining that with the short residency period of CO2 [see: http://c3headlines.typepad.com/.a/6a010536b58035970c0120a5e507c9970c-pi%5D means that there is no effective distinction between TCS and ECS.
In respect of George’s calculations/observations, the key is the window which Trenberth has guessed/estimated; if for example Miskolczi is right and the window is bigger that would explain the lack of heat build-up in either the oceans or the atmosphere; a far more plausible explanation than looking for missing heat or postulating century long delayed effects from AGW. Get real!
10
KR,
My calculations can be validated by another way. Since half of what’s absorbed escapes, the net transmittance of the atmosphere, relative to the surface, is equal to 0.241 + (1-0.241)/2 = 0.62. The surface gain is then the reciprocal of this, 1/0.62 = 1.61. So what you are saying is that this is yet another coincidence that the surface gain calculated based on net transmittance is equal to the measured surface gain.
In fact, there’s a very simple formula that calculates the surface power from the albedo, transparent window size and the incident solar power. The formula is,
10
Sorry for the inadvertent post. My thumb accidentally hit my mouse pad while the cursor was over ‘submit’.
The formula is,
surface_power = solar_power*(1-albedo)/(T + (1-T)/2)
For solar power = 341.5 W/m^2, albedo = 0.3 and T = 0.241, the calculated surface power is, 385.2 W/m^2.
Can you tell me why this also works if my calculations are in error?
20
cohenite – Considering that surface sea temperatures are going up, and oceans are kilometers deep, there’s quite a bit of thermal mass to absorb the energy and delay a response. It takes time for vertical mixing and heat exchange. I’m looking for the reference now (darn it, didn’t bookmark it), but there are recent results indicating warming of deep (bottom of ocean) Antarctic currents to/from other ocean basins.
CO2 has a logarithmic effect – yep. That doesn’t mean it has _no_ effect, which is what you seem to be stating in #31. As to residency time, an individual CO2 molecule may only be in the atmosphere for ~5 years or so on average, but given the constant cycling of CO2 to/from the oceans, plant life, etc., the residence time is more like 500 years.
G. White has calculated a difference (imbalance) of 3.6 W/m^2 at top of atmosphere for doubling of CO2 – that imbalance is going to warm things. 3.6-3.7 W/m^2 over the surface of the Earth is a lot of power.
co2isnotevil – Albedo is a red herring in this discussion. The extra energy at the surface is thermal IR, not reflectance. And as the surface heats, so does the low level atmosphere (more back radiation), meaning not all of the surface warming will be directly expressed as TOA radiation. Add in that increasing CO2 levels raise the effective stratospheric radiation altitude to space (colder CO2, less energy emitted, more warming of the surface) – The surface warms up.
10
KR,
Albedo is not a red herring. If as you say, 3.7 W/m^2 becomes 16 W/m^2 at the surface, where is the extra 12.3 W/m^2 coming from? It can only come from a reduced albedo. Conservation of Energy rules here and you can’t simply create 12.3 W/m^2 out of thin air.
10
Dammit, I burnt another date last night when she started intimating how she’d like to throw western society under a bus in the name of sustainability. Apparently explaining what a Malthusian catastrophe is and why we’ve never had one is a real mood killer! She was only interested in how she ‘felt’ about issues, textbook leftist who abhors the west and capitalism but happily enjoys it’s benefits and protections. She concluded by saying “I still don’t like mining”, I called her childish and she stormed off, I promise you it was worth it. I just find it so incredibly unattractive and I can’t look past it, any other guys having this same problem?
10
KR,
You claim,
By this, I suspect you mean the half life, as that is all that is really relevant. Measured CO2 show both increases and decreases of about 1ppm per 2 months. Assuming no new CO2 is added to the system, a decrease of 1ppm per 2 months is 6 ppm per year, which at 380ppm would be down to 0 in only about 16 years. While it’s true that an individual molecule of CO2 can stay in the system longer, especially when new CO2 is continually added, the half life of atmospheric CO2 as a whole is less than 10 years.
You also claim that I agree about a 3.7 W/m^2 ‘imbalance’ caused by doubling CO2. Let me refer you back to post 26 where I explained what I do agree is that the 3.7 W/m^2 represents incremental absorption, but that only half of this reaches the surface and us subject to feedback or gain amplification.
10
KR
http://www.ncasi.org/publications/Detail.aspx?id=3152
the oceans are cooling.
10
Wilko,
When it comes to dating women with opposing political views (here in the SF Bay area, it’s most of them), it’s always best to agree to disagree.
10
I am confused. Where is energy transfer due to convection? The IR re-radiated downward is going to be available to be used for surface heating and evaporation and acceleration of the convection system. I read an estimate that 92% of the energy input could be transferred by convection of warm air to altitude and then release of the heat of condensation of the water vapor carried to altitude. This would be a big part of the puzzle, but I do not see it referred to here. Am I missing something?
10
Detailed explanations of specific mechanisms just don’t cut it down at the pub or the coffee lounge. I’m trying to come up with a ‘sound bite’ that’s accurate and easily digested. How’s this for a start?
10
Your terminology is confusing. I can imagine only one way that the Earth’s incoming and outgoing energy can be imbalanced as a steady state: That is for the Earth to be a net producer of energy. Interestingly, the Earth is a net producer of heat, as is shown by the temperature gradient in the ground. However, at 0.02% of the Solar flux, this is probably in the noise.
It would seem to me that any calculation of the Earth’s long term heat budget MUST therefore start with the assumption that energy inflow and outflow are (nearly) equal.
Any imbalance is rapidly removed by the temperature changing until a new balance is reached.
10
Charles, re #40
Convection has no direct influence on the energy balance, which at the top of the atmosphere is strictly radiative. For the most part, convection simply reorganizes energy within the planets thermal mass, which is mostly ocean and partly atmosphere. While some power can be convected to the surface, relative to the energy balance, this offsets power that would otherwise be radiated to the surface and that this otherwise radiated power must be doing something else, for example, reversing the latent heat as water vapor condenses into rain.
The point of this exercise is to show that by considering only the radiative components, a balanced system emerges. To the extent that other forms of power enter and leave the surface and/or atmosphere, their net effect on the radiative balance must be exactly zero. I should also point out that in addition to the emergence of a balanced system, the 50/50 split is also an emergent property, although the physics of BB radiation dictates this to be the case.
10
co2isnotevil – Surface radiation is set by surface temperature, and the change in surface temperature is “climate sensitivity”.
Given your numbers, 3.6 W/m^2 imbalance at TOA, only 1.8 going to the surface of the Earth, with a 1.6 amplification factor, what does that do to surface temps? If we assume that all of that is radiated as IR (and it won’t be, it will increase thermal and evaporation transport to the atmosphere where some will be radiated to space), then:
385 W/m^2 + 1.8 * 1.6 = 387.88 W/m^2 radiated.
What’s the temperature change from that?
387.88/385 = 1.0075
Current surface temperature is 287.2K.
(New Temp)^4 / 287.2^4 = 1.0075, new temp = 287.74, or a climate sensitivity of 0.54C/doubling of CO2.
That’s the lowest estimate I have ever seen – Lindzen and Choi estimated 1.1, Schwartz estimated 1.0, and the IPCC estimates 2.5 to 4, with 3C the most likely number. I think you might be a bit off there…
10
Siliggy @ 17,
Are you sure you weren’t reflecting light from the lighted surface into the shadow of the mirror? I strongly suspect that is the case. Especially since you said the mirror was close to the surface and the light was overhead. You could not have avoided reflecting into the cast shadow. Consider that I said the reflected light from a bright portion could add to a darker portion of the surface. Thereby anticipating the form your experiment exhibits.
Replicate the experiment correctly please!
10
This has been an interesting debate to follow and i must admit that i have nothing to add as far as W/m is concerned but have learnt a lot reading all the posts.
I do have one question which is probably slightly O/T and i will address it to KR @28 simply because He/She raised a point that has always intrigued me.
KR, you stated “….and it’s going to take some time for the Earth to reach equilibrium with where we are right now – even if we locked CO2 levels at 390 tomorrow.”
I do not understand this statement and never have, the way i look at it there are forces at work on the planet that are constantly changing, sometimes working in concert with each other to either raise or lower the temp/heat content or sometimes working in opposition to each other.
Lets assume we have not produced any CO2, would the temp be going up, down or stable? From what i have read from the IPCC there are no -ve feed backs produced from increasing CO2 only +ve feed backs (more water vapour, less albedo, more methane etc)so therefore if CO2 is doubled and we get 3.7W/m increase in heat content then the temp must go up. This in turn warms oceans, melts ice etc increasing CO2 so our figure of 3.7 W/m must also go up producing more heat and so the process goes on.
So my question is how does the Earth reach an equilibrium?
10
Sphearica (Bob),
Odd, your posts came to be by email, but are not otherwise showing up. It’s probably in the moderated queue, but I will answer anyway.
First, the blanket analogy is not quite accurate. It would be more accurate to say it’s a blanket with holes in it covering 24.1% of it’s surface. Increasing absorption reduces the fraction of holes to about 23.2%. The extra 1.1% without holes traps a little more heat, but that heat eventually escapes from the 23.2% of the holes.
The energy absorbed by CO2 is vibrational or otherwise representable as a change in the quantum state, hence the discrete lines. Most of this is transferred to the other non GHG molecules in the atmosphere via collisions and little is actually re-radiated by the Co2. In fact, this is how GHG absorption heats the atmosphere.
A heated gas, like any heated object, emits a Planck spectrum of BB radiation proportional to it’s temperature raised to the forth power. In this case, the kinetic energy transferred to the O2, N2 and other gases is gradually released as broadband EM energy as those molecules slow down and cool. In effect, the GHG effect converts narrow band absorbed power into broadband emitted BB power, some of which is also subject to subsequent absorption. In this context, GHG’s delay the release of surface power and do not trap it. Again, this is an important distinction that many don’t get.
With regard to the Earth’s thermal mass, not all of the oceans mass actively participate. Remember that 80% of the oceans are below the thermocline and it’s average temperature is about 2C. This temperature is set by the density/temperature profile of water and will not change as long as the poles remain frozen, which of course will always be the case, at least in the winter, given that it’s dark for 6 months of the year.
The ocean stores energy as a temperature difference across the thermocline analogous to how energy is stored in a capacitor as a voltage difference between it’s 2 plates. Keep in mind that the cold terminal of the ocean capacitance, at 2C, is less than the average temperature of the planet, while the warm surface waters above the thermocline are greater than the average temperature. In fact, the average temperature of the planet is quite close to the temperature at the mid point of the thermocline, so in effect, the cold water (energy) at the bottom is offset by the warm water at the top and the net energy stored in the oceans, relative to the average surface temperature, is relatively small. This is why the planets average ocean temperature swings by several degrees C over the course of a year. If the oceans were as sluggish as you require to support CAGW, ocean temperatures would be very constant across the 4 seasons and we would see little, it any, seasonal climate variability.
10
DirkH @12,
The context was the AGW radiative forcing fantasy in which a warmed surface emitted IR that is subsequently absorbed by CO2 above it. The CO2 re-emits the IR back down to the surface thereby warming it still more. I demonstrated why that cannot happen. Exactly because the energy is simply transferred from one place to another and does not remain at its originating source. The first law of thermodynamics cannot be broken (ie you can’t have your cake and eat it too).
Sure, change the absorption characteristics of the surface and the system is changed. That will change the equilibrium temperature of the surface but the energy flux remains the same at the surface of the system. Your color change is not a part of the radiative forcing fantasy and is therefor irrelevant to the discussion about radiative forcing.
The logical error you are attempting to put over is called “moving the goal posts” or more technically “not holding context”.
10
co2isnotevil
No, it means what it says, that the relationship is not linear, but logarithmic. As you increase CO2 levels, the warming effect is proportional to the log of the increase, i.e. ∆T = ln(C/C0).
10
KR@37 and elsewhere; stop fibbing: you say:
“Considering that surface sea temperatures are going up”
They are not: latest:
http://www.drroyspencer.com/wp-content/uploads/AMSRE-SST-Global-thru-27-Oct-2010.gif
And trend:
http://www.drroyspencer.com/wp-content/uploads/AMSR-E_SST_thru_Nov_09.jpg
You say:
“CO2 has a logarithmic effect – yep. That doesn’t mean it has _no_ effect, which is what you seem to be stating in #31.”
I did not say this; I said:
“as Beenstock has shown CO2 only heats when it is increasing exponentially [due] to the logarithmic decline in heating effect; when it is increasing linearly or not at all it has no heating effect;”
As to residency of CO2, the studies I directed you to all consider recycling through the biosphere; one of the major extractions of CO2 is through oceanic deposition; dissolved CO2 in the ocean precipitates to form calcite which is deposited onto tectonic plates and recycled into the mantle; vast amounts of CO2 are removed from the system constantly by this process. CO2 is neither physically long-lived nor does it have a delayed effect beyond any effect from its exponential increase.
Spaerica@30 you say:
“The upshot is that if GHG theory is correct (and yes, I believe it is beyond any doubt), the planet will continue to warm substantially long after we curb CO2 emissions, and any temperature anomalies or trivial effects which people today attribute to climate change are nothing in comparison to what is coming for future generations.”
This really annoys me; it is a statement of faith distorted by paranoia; it really is dreadful. All over this world and in Australia we have so-called scientists like Karoly similarly screeching about the doom which awaits us; naturally Karoly is now saying the QLD floods are due to AGW and has received prominent coverage on our ABC for his ravings; what will get no publicity is a measured response to Karoly by Professor Stewart Franks a real expert on ENSO and evaporation; here is Franks’ reply to Karoly:
“Dear Mr Uhlmann
I would like to protest the repeated interviews with Prof David Karoly with regard to the Queensland floods.
Since 2003, I have published a number of papers in the top-ranked international peer-reviewed literature regarding the role of La Nina in dictating Eastern Australian floods.
There has been no evidence of CO2 in affecting these entirely natural processes, irrespective of their devastating nature.
Why is it then, that someone without any publication nor insight in this key area of concern for Australia is repeatedly called upon to offer his personal speculation on this topic?
This is not a new problem with Prof. Karoly.
In 2003, he published, under the auspices of the WWF, a report that claimed that elevated air tempertatures, due to CO2, exacerbated the MDB drought. To quote…
‘…the higher temperatures caused a marked increase in evaporation rates, which sped up the loss of soil moisture and the drying of vegetation and watercourses. This is the first drought in Australia where the impact of human-induced global warming can be clearly observed…’
The problem with this is that Prof Karoly had confused cause and effect.
During a drought, moisture is limited. The sun shines on the land surface, and as moisture is limited, evaporation is constrained, and consequently the bulk of the sun’s energy goes into surface heating which itself leads to higher air temperatures. This effect can be as much as 8-10 degrees celsius.
This is a common confusion made by those who have not studied the interaction of the land surface hydrology and atmosphere, as Prof. Karoly has not.
Undoubtably Prof Karoly has expertise but not in the area of hydrology or indeed in many other areas on which the ABC repeatedly calls on him for ‘expert’ comment.
Could I please ask that you cast your net a little wider in seeking expertise? These issues are too important for the media commont to be the sole domain of commited environmental advocates. Surely objective journalism also requires objective science?
Sincere best wishes,
Stewart Franks”
10
12 Jan 2011
Dear Mr Uhlmann
I would like to protest the repeated interviews with Prof David Karoly with regard to the Queensland floods.
Since 2003, I have published a number of papers in the top-ranked international peer-reviewed literature regarding the role of La Nina in dictating Eastern Australian floods.
There has been no evidence of CO2 in affecting these entirely natural processes, irrespective of their devastating nature.
Why is it then, that someone without any publication nor insight in this key area of concern for Australia is repeatedly called upon to offer his personal speculation on this topic?
This is not a new problem with Prof. Karoly.
In 2003, he published, under the auspices of the WWF, a report that claimed that elevated air tempertatures, due to CO2, exacerbated the MDB drought. To quote…
‘…the higher temperatures caused a marked increase in evaporation rates, which sped up the loss of soil moisture and the drying of vegetation and watercourses. This is the first drought in Australia where the impact of human-induced global warming can be clearly observed…’
The problem with this is that Prof Karoly had confused cause and effect.
During a drought, moisture is limited. The sun shines on the land surface, and as moisture is limited, evaporation is constrained, and consequently the bulk of the sun’s energy goes into surface heating which itself leads to higher air temperatures. This effect can be as much as 8-10 degrees celsius.
This is a common confusion made by those who have not studied the interaction of the land surface hydrology and atmosphere, as Prof. Karoly has not.
Undoubtably Prof Karoly has expertise but not in the area of hydrology or indeed in many other areas on which the ABC repeatedly calls on him for ‘expert’ comment.
Could I please ask that you cast your net a little wider in seeking expertise? These issues are too important for the media commont to be the sole domain of commited environmental advocates. Surely objective journalism also requires objective science?
Sincere best wishes,
Stewart Franks
10
Cohenite,
You forgot the email he sent to Karoly
David
Your comments on the role of CO2 in the Qld floods are speculative at best, immensely damaging at worst.
When will you accept that CO2 is not the answer to everything? When will you decline an interview for the lack of your insight?
Have you not learnt from your physically incorrect speculation about temperature and evaporation during the MDB drought? Do you have no shame to have confused cause and effect in such a brazen and public manner?
Is it enough for you that your pronouncements sound correct, irrespective of science? Have you learnt nothing?
You are arguably the best example of the corruption of the IPCC process, and the bullshit that academia has sunk to.
Shame on you
Stewart
10
KR,
So it seems you agree that half of the absorption is radiated up and half down, Your post here from earlier today (comment 51) indicates that you claim that the total atmospheric absorption is 7.4 W/m^2.
http://www.skepticalscience.com/news.php?p=2&t=64&&n=491
I can understand why you didn’t bring that up here, because you know how wrong this is. Even without considering the overlap of water vapor and the other GHG’s, doubling CO2 only increases absorption by 4.7 W/m^2. It becomes 3.6 W/m^2 when you consider the overlap between the incremental CO2 absorption and what would be absorbed by water vapor anyway.
10
cohenite,
There’s no reason to go back and forth on this, but from my perspective the same applies to people who refute AGW. To me, the scientific evidence is there, clear and undeniable, while those who refuse to accept the evidence and logic (to me) appear cling to a faith that it can’t be true, distorted by their own paranoia that addressing the issue will somehow cost them their position in society (i.e. “one world government” or “destroy the world’s economy” or whatever).
But… I will discuss science, and nothing more. The main point that I was trying to make was that because of the inertia in the system, attempts to quantify the eventual effects of CO2 on global mean temperature at this time, based purely on observations, is a futile activity. One must include a reasonable amount of knowledge of a complex system in one’s evaluation. Simple linear thinking, or an “it hasn’t happened yet, so it’s not happening” attitude are failing approaches to the problem.
10
Sphaerica; “the inertia in the system”; look up MEP; the only inertia in this ‘system’ will be manifest when we collide with another celestial body.
10
Just a real dozy question here…
Why does all the energy have to be re-emitted? Doesn’t some of it get transformed (say into plant biomass) and stay within the atmosphere? Then other biota consumes the plant material and converts it to some other stored energy.
I knew the obesity crisis was good for something.
10
This is some of the work that led to the 24.1% average T.
Here are the results from 5 atmospheric simulations runs. Four atmospheric zones are considered where the vertical profile is interpolated between the zone means and integrated from the surface to 50km. GHG’s, except H2O and O3, are considered uniformly mixed, while H2O and O3 follow a profile with a specific average concentration per zone. The zones are defined as follows:
Zone range Frac Pressure Temp @nominal surface temp
0: 0km to 3km, 30.54%, 0.84328, 278.855K (42.27F)
1: 3km to 6km, 52.65%, 0.58097, 256.050K ( 1.22F)
2: 6km to 15km, 88.11%, 0.28280, 226.323K (-52.29F)
3: 15km to 50km, 99.93%, 0.04252, 243.075K (-22.13F)
When 2 or more gases are absorbing the same wavelength, both are counted, but the total is accounted for as being contributed by only one gas. The gas selected will be the one absorbing the largest fraction of the total. Absorbed power is relative to the emitted surface spectrum at it’s average temperature.
The first result is the average clear sky absorption with nominal GHG concentrations. The clear sky absorption is 56.6%, while the average cloudy sky absorption is about 85.7%. For 66.6% clouds and 33.3% clear, the total absorption is .566*.333 + .857*.666 = 0.760, for a net 76% absorption and an average transparent window of about 24% and yes, I rounded this up to 24.1% for my energy budget.
The second is at 280 ppm CO2 with all else set to nominal.
The third is at 560 ppm CO2 with all else set to nominal. The delta absorption from the second case is 3.6 W/m^2, and while CO2 increases by more than this, the water vapor component decreases.
The fourth is CO2 at 280 ppm and everything else set to zero.
The last is CO2 at 560 ppm and everything else set to zero. Here, the delta is 4.79 W/m^2. With the water vapor missing and not otherwise absorbing in overlapping bands, the effect of CO2 by itself will be larger.
1) ***************************************************************************************
model type = ‘Monthly T’, res=0.100 nm @ 1u, 23026 samp/decade, Ascale=1
Water Content: 1000:1300:144:1 ppm, Cloud Coverage: NOM, Surface Ice: NOM
Absorption: CO2: 383 ppm, CH4: 1745 ppb, O3: 30:80:150:300 ppb, N2O: 300 ppb, CO: 100 ppb
absorption component breakdown:
H20 = 116.7797 W/m^2, fraction = 0.354451
CO2 = 57.5560 W/m^2, fraction = 0.174695
O3 = 5.2293 W/m^2, fraction = 0.0158721
CH4 = 3.5440 W/m^2, fraction = 0.0107568
N2O = 3.3771 W/m^2, fraction = 0.0102503
CO = 0.0558 W/m^2, fraction = 0.000169222
O2 = 0.0053 W/m^2, fraction = 1.62356e-05
total = 186.5472 W/m^2, fraction = 0.56621
force = 93.2736 W/m^2, fraction = 0.283105 50% up, 50% down
2) ***************************************************************************************
model type = ‘Monthly T’, res=0.100 nm @ 1u, 23026 samp/decade, Ascale=1
Water Content: 1000:1300:144:1 ppm, Cloud Coverage: NOM, Surface Ice: NOM
Absorption: CO2: 280 ppm, CH4: 1745 ppb, O3: 30:80:150:300 ppb, N2O: 300 ppb, CO: 100 ppb
absorption component breakdown:
H20 = 117.0733 W/m^2, fraction = 0.355343
CO2 = 55.5709 W/m^2, fraction = 0.168669
O3 = 5.2355 W/m^2, fraction = 0.0158908
CH4 = 3.5426 W/m^2, fraction = 0.0107524
N2O = 3.4168 W/m^2, fraction = 0.0103707
CO = 0.0551 W/m^2, fraction = 0.000167238
O2 = 0.0053 W/m^2, fraction = 1.62356e-05
total = 184.8995 W/m^2, fraction = 0.561209
force = 92.4498 W/m^2, fraction = 0.280605 50% up, 50% down
3) ***************************************************************************************
model type = ‘Monthly T’, res=0.100 nm @ 1u, 23026 samp/decade, Ascale=1
Water Content: 1000:1300:144:1 ppm, Cloud Coverage: NOM, Surface Ice: NOM
Absorption: CO2: 560 ppm, CH4: 1745 ppb, O3: 30:80:150:300 ppb, N2O: 300 ppb, CO: 100 ppb
absorption component breakdown:
H20 = 116.4037 W/m^2, fraction = 0.35331
CO2 = 59.9992 W/m^2, fraction = 0.18211
O3 = 5.2580 W/m^2, fraction = 0.0159591
CH4 = 3.5451 W/m^2, fraction = 0.0107602
N2O = 3.2633 W/m^2, fraction = 0.00990468
CO = 0.0543 W/m^2, fraction = 0.000164875
O2 = 0.0053 W/m^2, fraction = 1.62356e-05
total = 188.5290 W/m^2, fraction = 0.572226
force = 94.2645 W/m^2, fraction = 0.286113 50% up, 50% down
4) ***************************************************************************************
model type = ‘Monthly T’, res=0.100 nm @ 1u, 23026 samp/decade, Ascale=1
Water Content: 0:0:0:0 ppm, Cloud Coverage: NOM, Surface Ice: NOM
Absorption: CO2: 280 ppm, CH4: 0 ppb, O3: 0:0:0:0 ppb, N2O: 0 ppb, CO: 0 ppb
absorption component breakdown:
H20 = 0.0000 W/m^2, fraction = 0
CO2 = 57.9766 W/m^2, fraction = 0.175971
O3 = 0.0000 W/m^2, fraction = 0
CH4 = 0.0000 W/m^2, fraction = 0
N2O = 0.0000 W/m^2, fraction = 0
CO = 0.0000 W/m^2, fraction = 0
O2 = 0.3406 W/m^2, fraction = 0.00103377
total = 58.3172 W/m^2, fraction = 0.177005
force = 29.1586 W/m^2, fraction = 0.0885026 50% up, 50% down
5) ***************************************************************************************
model type = ‘Monthly T’, res=0.100 nm @ 1u, 23026 samp/decade, Ascale=1
Water Content: 0:0:0:0 ppm, Cloud Coverage: NOM, Surface Ice: NOM
Absorption: CO2: 560 ppm, CH4: 0 ppb, O3: 0:0:0:0 ppb, N2O: 0 ppb, CO: 0 ppb
absorption component breakdown:
H20 = 0.0000 W/m^2, fraction = 0
CO2 = 62.7645 W/m^2, fraction = 0.190504
O3 = 0.0000 W/m^2, fraction = 0
CH4 = 0.0000 W/m^2, fraction = 0
N2O = 0.0000 W/m^2, fraction = 0
CO = 0.0000 W/m^2, fraction = 0
O2 = 0.3406 W/m^2, fraction = 0.00103376
total = 63.1051 W/m^2, fraction = 0.191537
force = 31.5526 W/m^2, fraction = 0.0957687 50% up, 50% down
10
Cohenite…. Those were excellent remarks by Professor Stewart Franks. I hope Uhlmann takes heed of what Franks suggested when seeking expert scientific opinion in future.
10
Grant,
Yes, you are correct that some of the solar power is converted into biomass, but on average it’s only on the order of a few W/m^2 and more or less rolled in with the other numbers.
10
Sphaerica (Bob) @ 30
Good idea. Now, scroll up to Lionell’s post at Number 6, read it and explain GHG in light of thermodynamics.
10
Looks like Jo stirred up a hornets nest of the CAGW faithful with this post.
To Wilko: I hear you mate. Luckily I am married to someone who, while not scientific by training, has a fairly decent bulldust detector (yes this works on at least two levels). Needless to say she does not buy the CAGW line of scaremongering either.
So Sphaerica, how is preteneding to be generally superior to other humans working out for you? Laying down some insults and then saying “oh but I only want to discuss the science” is rank arrogance. I would have thought your last thorough trouncing here would have kept you away, but clearly the absence has made you bolder again.
Personally I have a little trouble accepting as “fact” the products of assumptions mangled by computer modelling. As I have spent some time modelling in economics, a field which deals with similarly tricky systems, I have a good understanding of the severe limitations of modelling in general. I can easily generate future forecasts for a number of drastically different scenarios in economic systems by tweaking the assumtions by minor increments. I don’t bother because it is a complete waste of time and resources. Until the climate science is properly understood (i.e. such minor variables like clouds for example <– yes, the minor was sarcasm) the climate models are a similar waste of time and money.
10
Grant,
Of course it’s not up to skeptics to disprove AGW. In fact most skeptics, including myself, believe that the AGW effect is not zero and even the alarmists believe that the intrinsic effect of doubling CO2 is only about 1C.
It’s up to the alarmists to prove CAGW, which is the massive, otherwise unexplainable, amplification that’s applied to an intrinsically small effect which transforms it into a catastrophically large effect. The enhanced greenhouse effect and the subsequent catastrophic consequences is the extraordinary claim that requires extraordinary proof. Almost all of the warmist ‘science’ concentrates on the catastrophic consequences that would arise from a 3C or larger warming (most of which are highly exaggerated anyway) and no science whatsoever supports how the small intrinsic effect from incremental atmospheric absorption is so massively amplified, while solar energy is not.
10
http://eureferendum.blogspot.com/2011/01/dance-of-trolls.html
This describes perfectly what we are seeing here right now.
10
I have never actually seen Trenberth’s partitioning of the spectral contributions to his radiance balances, not have I seen his breakdown of specular and diffuse spectral reflectance.
I think he pulled his values right out of his
imagination.
10
Lord, this has been a dreary thread. Talk about “The Fighting Formulae”. Let’s get back to the real world now. Why aren’t we building huge greenhouses, pumping them full of ginormous amounts of CO2, and installing heat exchange turbines in them? That way we would have limitless amounts of virtually free, green-as-you-can-get energy for the entire planet.
Hasn’t happened, has it?
Well, it’s not because clever real world engineers haven’t contemplated it. They have, and they know it won’t work.
(Not an original thought of mine, alas. I read it somewhere a couple of years ago but can’t rightly recall.)
10
LevelGaze,
If you think this won’t work, explain why and then explain why it does work and why it works at so many levels. Why is there such a strong tendency to reject Occam’s Razor just because the simpler explanation contradicts the pedantic view of how the climate must work in order to support CAGW?
10
Mark,
I wouldn’t call too much of the activity trolling, at least in this case. It’s pretty much stayed on topic so far. I want warmists to offer reasons why it doesn’t work so that I can explain why they’re wrong. It doesn’t matter to me that many of the reasons are silly.
10
@co2isnotevil
I think it won’t work because if it could it would have already been done, so second part of your question is irrelevant. And, I’m sorry, I just don’t understand your second sentence 🙂
10
LevelGaze,
Tell me then, who did this and why didn’t it work? What doesn’t work about it? As far as I can tell, the only thing it doesn’t do is explain CAGW (Catastrophic Anthropogenic Global Warming). It explains and quantifies AGW as well as the steady state of the climate system. Why isn’t this enough?
10
@co2isnotevil
Ah, this is fun. As far as I know, no-one’s ever tried it, which is surprising given the unending spiritual quest for The Perfect Perpetual Motion Machine. 😉
If someone had already done it, and it worked, the whole of humanity now would be his/her/its slaves in thrall forever.
(Might just go out now and build myself a bloody big greenhouse…)
10
LevelGaze,
Sorry, but the fun’s over unless you have something useful to say. I’m done with you. As long as you actually read through the thread, that’s all that matters. When you chip away at the foundation of a false belief system, the rest of the house of cards rapidly collapses.
10
co2isnotevil
Aw, spoilsport…
just thought I was doing my bit of chipping. See you later.
10
George, re: your atmospheric spectral decomposition at 60; Steve Short, a sceptic but critic of Miskolzi has done his own analysis of atmospheric flux and came up with this, he uses Miskolczi terminology which I assume you are familiar with:
“Something very roughly like the following (assuming constant F, S_U and OLR across all cloud covers – which is not strictly true of course):
Assumptions:
S_U = 396 = constant
ET = Evapotranspiration
ET_U = LW IR emitted to OLR by clouds (as above) = 0.375ET
OLR – (ET_U + S_T) = ‘the real E_U’ denoted rE_U
Old E_U = ET_U + rE-U by definition
A_A = S_U – S_T (by definition and as per Miskolczi)
DT = Dry Thermals ~ 17 @ 60% cloud cover
K = ET + DT (by definition and as per Miskolczi)
F = absorbed SW IR (as per Miskolczi)
E_D ~ 0.625(ET + DT) + 0.5F + 0.625A_A on the grounds: (a) SW IR absorbed throughout entire atmosphere but(b) LW IR absorbed below the clouds.
Cloud%, Tau, S_T, ET, ET_U, DT, rE_U, A_A, E_D, Old E_U
100, 3.58, 11, 133, 50, 0, 178, 385, 362, 228
80, 2.94, 21, 107, 40, 8, 178, 375, 345, 218
60 2.55, 31, 80, 30, 17, 178, 365, 328, 208
40, 2.27, 41, 53, 20, 23, 178, 355, 288, 198
20, 2.05, 51, 27, 10, 29, 178, 345, 302, 188
0, 1.87, 61, 0, 0, 34, 178, 335, 270, 178,
Note: S_U does not = 2 x old E_U except around 40% cloud cover.
A_A does not = E_D (not required).
LW IR Tau is not constant (not required).
LW IR homeostasis arises through constancy of sum of (ET_U + S_T) and constancy of rE_U and proportionality of OLR to incoming Fo
This approach unifies the roles of the important K and F terms (which Miskolczi essentially ignored) into the all sky global energy balance/framework.
It shows how and why they are critical to a concept of low CO2 sensitivity ‘homeostasis’ applying across the full range of cloud covers (which of course applies naturally), in line with Lindzen’s concept of negative cloud forcing (iris).
At least for LW IR and the role of ET and clouds, this is the core issue which IMO Miskolczi singularly failed to address (despite a massive smoke screen).
Miskolczi’s so-called ‘constant tau’, so-called elimination of the surface/atmosphere temperature discontinuity and the so-called Atmospheric Kirchoff Law were all irrelevant distractions.”
Thoughts?
10
Sphaerica (Bob):
I don’t think I’ve ever read anything on this site arguing against “GHG theory”.
I dare suggest that Jo and many posters here accept that human CO2 emissions are affecting the climate but, on the evidence of 60+ years of AGW (according to the IPCC) not enough to reverse the enormous gains in overall human welfare achieved in the last 200 years or so, just as those benefits are beginning to extend to the 2/3 of humanity denied it until now.
In the face of a static global temperature for over a decade while the CO2 concentration went from 370 – 390 ppm, mockery of the ‘hockey stick’, ‘climategate’, etc. etc., alarmists need a new approach (or is a revival of the old approach?).
No need for empirical evidence — there’s a lag in the system, you ain’t seen nothin’ yet.
10
Manalive:
I must admit I almost laughed when I read Sphaerica’s line about lag in the system. It’s the you-won’t-see-the-evidence-yet-but-trust-me-you-are-all-going-to-die laughable rubbish you expect to hear from a demented doomsday preacher on a soap box in the park. As always … Python to the rescue:
http://www.youtube.com/watch?v=fIRb8TigJ28
10
cohenite,
My steady state average response, expressed in Miskolczi notation would be,
(Ed – K) + Eu = Aa
and
Eu = (Ed – K)
10
Actually, Uhlmann is a self-confessed global warming skeptic, and proud to be. Sorry, don’t have a link for that,
10
George #70
Seen the same thing too many times now George. These people breeze in, throw wildcards around but are very careful not to actually engage in discussion. They aren’t the least bit interested in anything remotely resembling a rational discussion.
10
Hi George; Miskolzi’s equilibrium eqn is number 4:
AA = SU A = SU (1−TA) = ED
That is AA = ED, where AA is the atmospheric absorbed part of SG or SU which is the upward LW radiation from the surface, and ED is the down LW radiation from the atmosphere; EU is the LW upward radiation from the atmosphere and K is the non-radiative thermal from the surface. Given that I’m not sure how (Ed – K) + Eu = Aa and Eu = (Ed – K).
10
Hi George: While I am also a global warmign sceptic I have to disagree with some of the things in your article. Firstly the action of GHG in the atmosphere.
These gases undoubtedly absorb energy at their characteristic wavelength and in turn they also radiate at the same wavelengths at an intensity governed by their temperature. Thus energy at the GHG wavelengths is continuously absorbed and re-emitted as one travels up the GHG column. Spectroscopists define the power to absorb energy at a particular wavelength in units of absorbance where 1 absorbance (abs) means 90% of the energy is absorbed, 2 absorbance means 99% is absorbed, 3 abs 99.9% absorbed and so on. The last 2 absorbance of the GHG column will absorb 99% of the energy at the characteristic wavelength percolating up from below. Which in engineerign terms is more or less all the energy. This 2 abs layer will also emit with an equivalent emissivity of 0.99 which is essentially a black body. Thus all the emission to space at the ghg wavelength comes from the top 2 abs of the ghg column. That means the impact of ghg’s in the atmopsphere is to block emission from the surface (only at the ghg wavelengths of course) and replace it with emission from the top 2 abs of the ghg column.
So how does all this relate to CO2. Well at 280 ppm the CO2 column is 2000 abs thick so only the top 0.1% of the column can radiate to space. SO what is the temperature of this top 0.1%? Well if the atmosphere were well mixed it would be high up in the stratosphere. But up there the temperature is not too far different from the surface so the emission would not be all that much less than the surface and CO2 would have essentially no impact as a ghg. However we have the emission plots from the IRIS experiment abord the Nimbus satellite and these show very clearly that the emission temperature is 220k which is the temperature of the tropopause. That in turn suggests the stratosphere is NOT well mixed with respect to CO2 (note this is in conflict with established wisdom!) The Nimbus data would seem to be extremely reliable. If we accept it the impact of CO2 is to replace emission from a 288K surface with emission from a 220K surface. The same Nimbus data shows the CO2 absorption band stretches from 14 microns to 16 microns. If I integrate Planks equation between 14 and 16 microns at 288K the emission is 38 watts/sqM. AT 220K the integration yields 13 watts/sqM. The difference 25 watts/sqM is the energy retained by CO2.
Now we know that the response to increasing CO2 is logarithmic and this logarithmic relationship starts at the point where the line centre saturates. This is at about 2 abs at which point the energy retained is still very small because the line is so narrow. Thus essentially the entire 25 watts is due to the 1000 fold increase from 2 to 2000 abs. This is almost exactly 10 doublings (2^10=1024) and that yields 25/10 or 2.5 watts/sqM/doubling. I will continue in the next post.
10
To continue;
The balance between surface and atmospheric emission from earth. The atmospheric window extends from 8 to 14 microns. Integrating planks equation fover this wavelength band yields 164 watts/sqM. Energy which cannot be intercepted by ghg’s although it can be intercepted by clouds. In addition there is surface emission in the region above 16 microns between the water absorption lines. This suggests the emission from the surface to space is far more than the 40 watts/sqM claimed by Trenberth and possibly more than the 93 watts/sqM you mention. The same Nimbus emission plot confirms this. The area under the curve is the total emission to space. The equivalent temperature (given by the overlaid Plank curves) at each wavelength gives strong indication of the source of the emission at that wavelength. If you look at the curves it is clear the emission betwen 8 and 14 microns is coming from the surface (nothing else is as hot as that) and the area in that region is far over 50% of the total area. Addin some of the area under the curve above 16 microns and the emission directly from the surface is about 70% of the 243 watts/sqM total or about 160-170 watts/sqM. The atmosphere can only emit at the ghg wavelengths (it has essentially zero emissivity at other wavelengths) and as discussed in the previous comment for CO2 this emission comes from the tropopause at 220K. It turns out (for reasons too lengthy to go into here) this is also the case for water vapour. (for ozone it is near the top of the stratosphereagain for very good reasons). Now even a black body at 220K can only emit 132 wattsq/sqM. If we leave out the atmospherci window where we know the atmosphere cannot emit that figure drops to 87 watts/sqM and the total emission must be less than that because water does not absorb and emit at all wavelengths above 16 microns. If we take the surface (and cloud top) emission at 170 watts/sqM that leaves 243-170 = 73 watts/sqM which is very consistent with the above.
10
Going further;
Given the calculation that doubling CO2 retains an extra 2.5 watts/sqM can we calculate the “direct” impact on surface temperature? Well consider that according to the Stefan Boltzman equation a black body at 288K emits 390 watts/sqM. The Earths surface however only succeeds in emits about 170 watts/sqM out to space. While not entirely accurate we could approximate this situation by treating the sruface as though it had an effective emissivity of 170/390 = 0.44. (note this is not entirely accurate but is reasonable because the emission wavelengths cover a reasonable spread across the whole spectrum). Differentiating the Stefan boltzman equation gives the sensitivity or watts/sqM per degree C. At 288K this comes to 5.4 watts/sqM. If we now factor in the “equivalent” emissivity of 0.44 the figure is reduced to 5.4 * 0.44 = 2.4 watts/sqM/C.
Hence an increase in energy retention of 2.5 watts/sqM yields a surface temperature rise of 2.5/2.4 or 1.04C. Given the accuracy of these calculations approximately 1C rise.
10
[…] 4. Jo Nova on Half Of The Energy Is Flung Out To Space […]
10
You say early on in your article that of the energy absorbed by the atmosphere, half is directed back to space as incremental albedo. I cannot agree with that. Albedo is due to energy reflected back to space at the same wavelengths. This energy is not reflected, it is absorbed and goes to heating the atmosphere so it does not appear as albedo. Does half get directed back out to space? No I don’t think so. Most of this energy is near infra red energy absorbed at the water vapour lines. But the absorptivity of water vapour in the near IR is similar to that in the mid IR. If the water column is effectively emitting from the tropopause at the mid IR lines it is dense enough at that altitude to be absorbing strongly in the near IR. This means most of the energy is absorbed very high up in the troposphere. This absorbed energy increases the temperature of that region and causes it to emit more strongly in the mid IR (it is still too cold to emit in the near IR). Of course half of that emission is out to space and half directed down towards the ground. However, the half directed down towards the ground has exactly the problem in reverse as the energy radiating up from the surface. It is very rapidly absorbed by the gas below it which in turn heats and thus radiates more – half up and half down. In fact almost none of the energy will make it down to the surface it will all end up being radiated back out to space as long wave IR from the tropopause.
In effect the massively thick ghg column isolates the surface from the tropopause and the two act as at best very weakly coupled systems. Of course they are coupled by convection but the question in my mind is; is the tropopause temperature determined mainly by convection or mainly by a balance bewteen near IR absorption from sunlight and long IR emission to space. I suspect the latter but I freely admit I have no proof at this time – its just an hypothesis.
10
Karoly’s “global warming” – wetter, drier, worse, better, whatever…………
http://blogs.news.com.au/heraldsun/andrewbolt/index.php/heraldsun/comments/karolys_global_warming_wetter_drier_worse_better_whatever/
10
I detect FEAR and DESPERATION amongst the trolls (LevelGaze, KR, Sphaerica (Bob), socold) that the wheels have fallen off their GRAVY TRAIN (otherwise known as the FRAUD of man made GLOBAL WARMING)……..
Best to polish up your CV’s boys and get ready to queue up at the UNEMPLOYMENT OFFICE!
You MAY get work as street sweepers if you are extremely lucky but I doubt it!
10
Percival, please, that’s insulting street sweepers.
10
Our poor old planet, much misunderstood. Climate- The result of the world seeking equilibrium in a chaotic but robust and simple heat pump system. The sun as the heat source, the oceans the refrigerant and the atmosphere an unbounded plumbing system.
Various vagarities in the input of heat caused by a multitude of ever varying parameters such as ever changing wobbles and alignments, can cause some rather severe fluctuations. The sun also has habit of being rather temperamental.
We live in the unbounded plumbing of a heat pump trying desperately to reach equilibrium. It is chaotic, unlinear and hence always tending to simplicity and beauty in a manner so complex we are confused and in awe.
Mr White, you have shown a small part of the energy balance, the thermostat of our wonderful world is controlled by many subtle things and some brutal ones, such is life living in the plumbing.
10
Sphaerica @30
This has been a very informative discussion with excellent input from CO2isnotevil and Cohenite and to a lesser extent KR. KR at least seems to follow the science and understand the issues and until I read you at 30 I thought you did also:
“The upshot is that if GHG theory is correct (and yes, I believe it is beyond any doubt), the planet will continue to warm substantially long after we curb CO2 emissions, and any temperature anomalies or trivial effects which people today attribute to climate change are nothing in comparison to what is coming for future generations.
Any argument against GHG theory by claiming that there is no substantial warming or undeniable empirical evidence (yet) is like the guy who jumped off the top of the Empire State Building and was heard to say, each time he passed an open window, “so far, so good.”
I know this sentiment will bother most people here, and I apologize for that, but it is in fact the case. If you want to argue against GHG theory, try to do so with science and logic, not with suppositions based on what in climate-time amounts to very short term observations.”
It’s not so much the sentiment(s) you express that is (are) troubling, we are quite used to this sort of scaremongering irrational approach but rather your inability to rationally enter into a technical discussion re the cons and pros of what is still a contentious and developing science of the Earth’s climate. If you had been able to follow CO2isnot evil, an able and rational expositor of his position, you would not have descended into the irrellevance of your slightly crazy prophecies.
Maybe your attention span is the problem or maybe you really are out of your intellectual depth. Whatever the problem is your comments certainly do not advance any scientific understanding of CACC.
10
Bob Maloy,
I’m unsure why comments on sites like this or WUWT randomly devolve into insults. It’s unhelpful, and nothing that you would ever say to someone to their face (I would hope).
FYI, a troll is not simply someone who disagrees with you. A troll is someone who posts inflammatory or off-topic comments… of course, if you consider anyone who disagrees with you to be a troll, then you expect everyone with an opinion other than your own to simply shut up — not very democratic.
10
LlewJones,
scaremongering. irrational. inability. irrelevance. crazy prophesies.
All because I expressed a difference of opinion from your own, the moment I expressed it.
10
manalive,
No one anywhere is saying anything close to this. An annual investment of one to three percent of GDP (as estimate by economists) will transition the world to enough clean energy solutions to mitigate the problem within reason, as long as we begin soon. This process will simultaneously create new jobs and new industries, and result in many additional benefits (a cleaner world, strategic independence from foreign oil, protection against rapidly diminishing oil and coal supplies, and more).
The only people who will be hurt by this, in fact, are that 1/1,000,000 of the world population that enjoy ownership positions in oil and coal companies… like the country of Dubai, which can afford to build an indoor ski mountain.
“Reverse the enormous gains” is gross exaggeration and scaremongering. It will only come anywhere close to that if we wait so long to begin to address the problem that frantic, drastic action becomes necessary.
10
Hi everybody
I’m late to this thread but I took the time to read all of the 90 comments to date.
I wish to support Sphaerica (Bob)in the sense that his posts have been polite and reasonable and worthy of discussion. I would encourage others to engage him without ‘having a go’ at him.
——————-
Sphaerica (Bob), I have a suggestion for you.
Take a thermometre to bed with you tonight. Lets say your body generates 36.5C.
Pull a blanket over yourself and measure the T of the cavity between you and the blanket.
Now keep adding extra blankets, see if you can get the T in the cavity up to 2 x 36.5 = 73C
If the T in the cavity reaches 73C, your CO2 blanket analogy has a fighting chance.
If the cavity doesn’t reach 73C, your blanket analogy is null and void.
I’m happy to settle for approximate numbers. Let me know how you go.
10
Just come to this site over the last week or so and enjoy the discussions. on this thread there has been mention of the conversion of vibrational energy to translational thus heating of the atmosphere.
Now I understood that the co2 absorbed energy was re-released almost immediately! Yes I know it is all relative. However does anyone have the mean time between collisions relative to this re-release and therebye we can calculate the amount of energy converted to translation. Or point me to a site where this info is available.
As far as the original post is concerned it carries as much weight as IPCC estimates and unless I spend a few hours going through the figures and ideas I would not judge one better than others. I am a simple soul and this seems to follow the same obfustication found in IPCC reports.
SORRY!
10
No need to be sorry, Bill!
Relaxation times are of the order of mean free collisions, which, at atmospheric pressure down to a tenth of it, are negligible with respect to the rates of the combined heat transfer modes.
It is the IPCC that has obfuscated, whereas George has attempted to remove it, by calculating the actual spectral contributions of incident insolation that could possibly contribute to “global warming” (if any).
IPCC does with it at their will in their attempt to make “global warming” unquestionable.
10
Sphaerica (Bob)@ 94
“All because I expressed a difference of opinion from your own, the moment I expressed it.”
No. You don’t know what my opinion is on radiative forcing or energy balance. The differences of perspective from the various contributors led to a very thought provoking discussion, including michael hammer’s contribution which I somehow missed earlier.
You really went off in 30 on an irrelevant, scientifically unsupported rant about your personal belief system which came across as an attempt to shut down the discussion. That you then play the poor victim who was only trying to help may indicate you get a bit of masochistic enjoyment from setting yourself up and is perhaps the reason you fire off these outbursts when you are in erudite company?
So there you have it; irrelevant, not up to speed, masochistic OR instead one who tries a bit harder to contribute in a more focused way to a discussion? The choice is yours.
10
Grant (63),
Sorry, I missed your comment until now. I already did address Lionell’s post at number 6. Scroll up to post 24 (January 13th, 2011 at 7:42 am).
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Brian G Valentine:
What I was trying to find out is the relative amount of radiative energy lost to translational rather than re-radiated; or I am missing the point? I know that the longer time the radiation bounces about the more is converted to heat in this way.
Trying to form a theory but sometimes hitting basics that I try to get my head completely around. That is why I ask questions which to many appear silly. It’s just my way and I usually get there in the end.
Going back to Georges post. I now see his logic but think he is missing the AGW point. The Earth is not in equilibrium because the increased CO2 is shifting the equation as happens in chemistry when concentrations of reactants change.
I was a believer then investigated and became a sceptic. In fact to my mind both sides are arguing in circles when relatively simple experiments with CO2 should be able to clear much confusion.
10
Llew Jones,
I posted a fair amount of science. I haven’t seen you address any of it.
Is there any specific point (in the science) that I made that you would care to address?
10
I’ve asked myself the same question.
My conclusion: It doesn’t matter, as the relative contribution to the (Maxwell-Boltzmann) distribution of k.e. of the exited molecules is imperceptible, if at all describable, to the contribution to the average temperature.
Trying to invoke a sort of “law of mass action” or “LeChatelier” analogy is on very shaky ground, this not a chemical equilibrium.
10
Bulldust,
Oh, yes, throughly. Not that I felt trounced, but rather that the environment here is so venomous and violent towards anyone that disagrees with the regulars that it is just uncomfortable for anyone else. The volume and ferocity of the comments, combined with the automatic down-vote for anything that isn’t rah-rah-no-AGW, regardless of the content, is extremely unpleasant and uncivilized.
So I look here rarely because of that and the fact that this site tends to focus on politics and such, rather than the science, and my interest only lies in the science.
But when I saw the number of people arguing back and forth about how CO2 radiates this way and that, without taking into account the important factor of energy transmission through collision (with O2/N2), I felt the need to at least help people to get over that particular misunderstanding.
10
Michael, re 83/84
What you say is true relative to radiation emitted by GHG molecules, but I actually don’t consider that GHG re-emitted power is specifically relevant to the energy balance. As you point out, the optical depth of the atmosphere in the bands absorbed by GHG’s is quite high. GHG re-emission will be at the same wavelengths that the GHG’s absorb and that photon will be quickly absorbed by another GHG molecule. But in order for the atmosphere to heat up, this absorbed energy must be transferred to the rest of the atmosphere. The probability that an energized CO2 molecule will re-emit an absorbed photon is actually quite low, relative to other mechanisms for redistributing this energy. Otherwise, the atmosphere would be very cold N2 and O2 mixed with a trace amounts of extremely hot CO2 and H2O, which the kinetic theory of gases says can not persist and the colder gas will be heated by the warmer gas until an equilibrium is reached.
When an O2 or N2 molecule collides with an energized GHG molecule, there’s a high probability that the vibrational energy of the energized GHG is translated into a velocity increase for both colliding molecules and it’s this transfer of energy that heats up the rest of the atmosphere which itself radiates a Planck spectrum according to it’s temperature. The part of this spectrum that leaves the planet comprises the difference between the surface power passing through the transparent window and the required emitted power in the steady state (255K).
When we look into deep space and observe the IR spectrum of a distant gas cloud, it radiates a BB spectrum of energy whose peak tells us it’s temperature and whose absorption gaps tell us about trace constituents of the gas cloud. Our atmosphere works in the same way, as does radiation from the Sun. The Sun does not deliver photons created by fusion, but photons emitted as BB radiation from the super heated gas/plasma at the Sun’s surface.
Regarding the 93 W/m^2 being too small, I contend that this is just that power passing through the transparent window. The window was calculated based on a line by line analysis accounting for all GHG’s, not just CO2, but you are right that the net transmittance is greater than the specific transmittance based on the size of the transparent window. In fact, if T is the window size, the net transmittance is T + (1-T)/2, where the T is the immediate power passing through the transparent window and (1-T)/2 is the delayed release of power absorbed by the atmosphere sometime in the recent past, half of which must find it’s way off the planet.
Another point is that Trenberth’s number is not really 40, but 70 since there is another ‘transparent window’ from cloud emissions which produces an additional 30 W/m^2. My equivalent of the 40 number considers 2/3 cloud coverage and a clear sky transparent window size of 43.4%. Given 385 W/m^2 of surface emitted power, the ‘Trenberth equivalent’ surface to space transparent window is 1/3 * 0.434 * 385 = 55.6 W/m^2.
10
Baa Humbug,
The problem with your experiment is that it removes all sources of external energy… the only source of heat is the body under the blanket. This is analogous to turning off the sun. You need to fabricate an equivalent experiment with a constant source of external heat which is able to easily penetrate the blanket from the outside (as visible wavelengths of light do through the atmosphere), while having less chance of escaping (as occurs with IR wavelengths in the atmosphere).
10
bill,
No, you are exactly right, and this is very important. In the denser lower troposphere, the chance of collision is far, far more likely than the mean time to re-radiate IR. The result is that CO2 in that environment acts to heat the surrounding atmosphere (O2/N2) which themselves radiate away their energy only very, very, very slowly, in very weak IR bands associated with (very minimal) rotational energy.
As you get higher and higher in the atmosphere, and it becomes more rarefied, the balance changes; less collisions, so more chance of radiating before a collision.
When you reach the stratosphere, the issue is completely reversed. There, it is far more likely that a CO2 molecule will radiate any vibrational energy away before passing it elsewhere in a collision. At the same time, it is also so rarefied that it is unlikely to even absorb IR. Most IR is going to pass straight through the stratosphere into space, uninterrupted. The most likely source of vibrational energy for a CO2 molecule will be a collision with an O2 or O3 (or other) molecule. The net effect is that CO2 in the stratosphere causes cooling (as evidenced by satellite measurements), while in the troposphere is causes warming.
10
bill,
Where do you feel there is confusion (that simple experiments with CO2 would clear up)?
[Any number of simple experiments have been done. Those that haven’t, aren’t simple, or maybe are simple but expensive to pursue.]
10
Pseudo science.
10
Sphaerica, re 107
You are almost right, but missing a key point. A heated gas emits a Planck spectrum based on it’s temperature as the kinetic energy of molecular motion is converted into EM energy by the relative motion of electron clouds with a near field net negative charge. Maxwell’s equations tell us why as moving relative charges -> changing E-field -> changing B-field -> propagating EM. The point is that the release of energy transferred to the O2 and N2 in the atmosphere is not imperceptibly slow, but dictated by Stefan-Boltzmann.
10
Sphaerica (Bob): #93
Go back and re-read earlier post, the phrase you have reprinted in your post (block quote), then question my motive for making it, is not mine.
10
The latest data from the US shows continued continental cooling since 1998.
http://thetruthpeddler.wordpress.com/2011/01/13/latest-official-government-data-shows-the-u-s-is-cooling-at-a-rate-of-9-4-def-f-per-century/
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Michael, re #87
It might help if I clarify what I’m trying to show here and why the approximations I’ve made are valid, even if they deviate from the specific internal processes in play, My goal was to quantify the required behavior of the atmosphere based on the boundary conditions between the atmosphere and space and between the atmosphere and the surface. Keep in mind that the behavior I derived at the surface boundary was a consequence of the behavior between the atmosphere and space, which by definition, is purely radiative.
Consider a hypothetical planet whose atmosphere has about the same amount of trace gas GHG absorption as the Earth, the same amount of N2 and O2, but has no water and all of the planets thermal mass is below the surface. In this case, my equivalent view of the energy balance is much closer to the actual physical mechanisms maintaining the balance. Where the current system gets complicated is with the movement of energy throughout the thermal mass. When contained within the oceans or atmosphere (i.e Hadley cell circulations), it is properly ignored. When the movement is between the oceans and clouds, where clouds comprise part of the thermal mass, the tendency is to count that movement as part of the energy balance, when it should more properly be ignored like the other circulation currents.
My equivalent view of the Earth is just as valid at quantifying the behavior dictated by the boundary conditions, but less accurate relative to representing the low level physical mechanisms establishing the balance, specifically between the surface and the atmosphere, once water is added and part of the active thermal mass of the planet is moved into the atmosphere. It’s also very important to recognize my simplified model is an equivalent model whose behavior at the boundaries matches the required behavior. That is, if the Earth’s actual atmosphere was replaced with an equivalent atmosphere with my specified behavior, the surface temperature would be exactly the same.
10
co2isnotevil,
I think you meant “transferred out of“, not “transferred to” — correct? I was not saying that the transfer of energy to O2/N2 is slow, quite the opposite, but that the resulting loss of energy (other than through physical interactions with the surface, not space) is slow.
In any event, I believe your statement is not quite correct. Stefan-Boltzmann only applies to a true black body, and absolutely does not apply without caveat and modification to gases or the atmosphere. The earth as a system (planet + atmosphere) can to a large extent be treated as a black body or a gray body in simple numerical models, but you cannot apply the same logic to the atmosphere alone, and specifically not to component molecules which are most definitely not black bodies.
In fact, it is this non-black-body nature (an atmosphere transparent to visible light, but partially opaque to infrared radiation) that is at the core of the greenhouse gas effect.
For all intents and purposes, at the temperatures in question in the atmosphere, O2 and N2 do not lose their energy through radiation in sufficient quantities to warrant discussion in the context of global heating/cooling.
At least, that is my understanding.
If you have a source which shows otherwise, please provide a link and I would be very pleased to read it.
10
Bob Malloy,
Sorry, I realize now it was Percival.
You were just “piling on.”
10
Sphaerica #114,
Yes, I meant that the the transfer out is dictated by SB, which while slow, is not imperceptibly slow and in fact is the primary source of the 146 W/m^2 at the top of the atmosphere required to supplement the 93 W/m^2 passing through the transparent window in order to match the steady state condition that the power entering the planet is equal to the power leaving.
Remember that we are talking about fluxes and in the steady state, the net flux across any arbitrary Gaussian surface in the system will be zero.
The idea that there’s some sort of perpetual short fall in the balance which accumulates surface heat is completely bogus, even in the steady state. If this was the case, the surface temperature would be monotonically increasing, which it certainly is not. Over the course of 1 year, half of the time the Earth is warmer than the incident energy can support and the planet cools, while during the other half of the year, the Earth is cooler than the incident energy can support and the planet warms.
Both local and global surface temperatures adapt very quickly (months and not decades to centuries) to changes in the incident energy, i,e, forcing. If this wasn’t the case, there would be little, if any, seasonal variability in the average surface temperature, when in fact, even the oceans show a substantial rate of change in response to seasonal solar variability.
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Sphaerica (Bob): #115
“Guilty as charged”!
cheers, Bob
10
Bill @ 97 – Excellent question. Here’s a reference, in particular Figure C, the transition drop through “laser”.
Relaxation times for CO2 are on the order of 10^-6 seconds. At sea level pressures a CO2 molecule will collide with other molecules 10^9 times per second. Therefore there are ~1000 collisions before a CO2 molecule can emit.
This means that CO2 will be at about the same temperature as the surrounding gas(es) – heating or cooling the entire air mass depending on the balanced of IR in and IR out.
10
crakar24 @ 49 – We’ve got a lot of variability in weather and climate – but at ‘equilibrium’ those variations will average out around some value for temperature, rainfall, winds, etc.
On the other hand, if something changes (in this case the amount of IR going into space due to greenhouse gases), those average values will change. This takes time, it takes energy, and there are various feedbacks that operate as well. In the case of the oceans warming (which, looking at a 30 year climate average, they are), it’s like putting a big pot of water on a small flame. It’s not going to change temperature instantly; it’s going to take some time until the heat coming off the top of the pot is equal to the heat coming in at the bottom.
Feedbacks, like changes in Arctic ice, albedo due to crops moving zones, etc., also take time, and will have their own effects. That holds for warming, for cooling, whatever.
In the case of CO2, the oceans and ice caps are still responding to the CO2 we’ve put in over the last 30-50 years or so; the pot is still warming up.
10
Folks – The CO2 and spectral discussion with George White is continuing over at Skeptical Science, where Hugo Franzen, a physical chemist with far more knowledge than I, is responding to G. White.
10
cohenite @ 53 – You say sea temps are not rising? I would invite you to take a look at the instrumental record, in particular the ocean temperature anomalies. 8-9 years (which Dr. Spencer presented in your links) is too short a time to see overall trends – noise is too high. An 11 year smoothing is about right for the amount of noise in the measurements and the ocean variability themselves; climate trends are going to only be statistically significant over 2-3 times that period, or about 30 years.
I will grant you that the 5-year curve is currently slowing a bit. But whether we’re seeing a change like in 1945 (reversal) or like 1965 (a wobble that resumes upwards) is going to take a few more years to become evident.
10
KR, you really can’t help yourself can you? The long term OHC graph is entirely consistent with PDO phases; are you blind? OHC has been dropping, as Spencer’s link shows [and incidentally NOAA revised down its OHC measurement in January 2010 see http://i48.tinypic.com/14e6wjn.gif ] since 2003, again consistent with PDO phase shift; it is isn’t slowing it is falling! As is TOA OLR; how can that be if you and Spaerica are correct about ‘stored’ heat?
I will grant you that your comment at 118 is correct; the rate of collisional deexcitation of the CO2 molecule is many times greater than the rate of excitation due to thermal radiation, absorbing a photon; in fact 99% of CO2 transfer of energy is through collision with N2 and O2, the vast bulk, 99%, of the atmosphere. BUT this collisional transfer is miniscule compared with the conductive heating of the N2 and O2 atmosphere through contact of that atmosphere with the surface of the planet.
CO2 is saturated at the lower levels; the CO2 below about 100 meters cannot absorb any further LW; nor can it transfer by collision since the bulk of the atmosphere is already energy loaded. What happens is that Local Thermodynamic Equilibriums are formed; inside an LTE, there is no movement of energy between an LTE and the surrounding atmosphere through either collision or radiation; LTEs are carried by convection to the Characteristic Emission Layer [CEL] where, because the atmosphere is less dense, radiative emission can occur. Michael Hammer @ 87 explains why water levels at the high troposphere/low stratosphere are so important for warming and it should be noted that water vapor at this level has been falling for some years [see the Soloman paper http://www.sciencemag.org/content/327/5970/1219.abstract ]
Sphaerica @ 107 and 114 has been upto mischief as well: at 107 he offers the conventional AGW reason for stratospheric cooling [SC] so SC can be regarded as an AGW fingerprint; it is a failed fingerprint: Spencer’s satellite measurements show this:
http://www.ssmi.com/msu/msu_data_description.html#msu_amsu_time_series
If you look specifically at TLS and TLT you will first note the following for TLS:
1978-1982 average flat
1982 El Chicon large volcao and following 2 years of spike up
1984-1991 drop to lower level than 1978-1982 and average flat
1991 Mt. Pinatube large volcano and 2+ years of spike up
1994-2010 drop to lower level than 1978-1982 and average flat
Now note for TLT:
1978-1997 up and down for several reasons, but average level
1998 very large ENSO
1999-2010 up and down for several reasons but average higher than 1978-1997 and essentially not varying in average. Most recent year high due to ENSO, but drop expected to follow from LaNino. Questionable where it will go from there.
The point of all of this information is that even though CO2 had a steady and large increase over this entire period, nothing that happened seems to be related to the CO2. The TLS has been essentially constant since 1994, and this period included the largest increase in TLT. In fact, essentially all of the increase in TLT occurred after 1998. This may help Justin understand the point even more clearly:
http://junkscience.com/MSU_Temps/Stratosphere1278-1204.gif
At 114 Sphaerica says this:
“For all intents and purposes, at the temperatures in question in the atmosphere, O2 and N2 do not lose their energy through radiation in sufficient quantities to warrant discussion in the context of global heating/cooling.”
This to me is one of the great black holes of the AGW debate; while it is true that N2 and O2 remmit at much lower intensity than CO2 and H2O, they do reemit, everything with a temperature above 0 does, but N2 and O2 are 99% of the atmosphere, the Earth’s ‘blanket’ to use AGW parlance; the energy which N2 and O2 have received, mainly through conduction with the surface, is used through work, convection. Therefore, it should be the case, if AGW is causing extra energy to be collisionally transferred to N2 and O2 that there would be more winds, more hurricanes, which in fact is another of the great predicted fingerprints of AGW; this is not happening, so as well as no energy being stored as OHC or a THS, we also see no extra energy being manifest as extra hurricanes.
How many failures can a theory have before its disciples like KR and Sphaerica wake upto themselves?
10
co2isnotevil #116,
I agree overall with much of what you say… not all of it, but nothing worth arguing about. Certainly nothing you’re saying is contradicting anything I’ve already said.
I’m not sure of the point of your last statement. I would point out that there is only a minimal change in global forcing with the seasons. The hemispheres see variations because of the axial tilt, and the effects are not entirely symmetric because of the uneven distribution of land masses and bodies of water, and the spread and retreat of ice at the north pole, but overall the seasons aren’t that relevant to a discussion of how quickly the entire system responds to changes in forcing.
Certainly the argument that seasonal temperatures in a hemisphere vary quickly because the system reacts quickly to subtle changes in forcing is fallacious. The hemispheric changes in forcing between the seasons are dramatic, well beyond any global changes in forcing that the planet has ever encountered in four billion plus years.
My only point here is to correct the people who were attempting to interpret GHG theory by imagining CO2 shooting infrared radiation through the atmosphere as if it were the only mechanism, when its not, by a long shot. Collisions which instead transfer that energy directly to the atmosphere are an important part of the mechanics.
10
cohenite @ 122 – I did agree in #121 that recent measurements are not showing much warming of surface temps; but I will still hold that given the variability shown in longer term records (as per my link in #121) we don’t have enough data to determine a long term trend yet.
I really hope longer term measurements show no warming, though.
Do you have references/data regarding outgoing longwave radiation values? If so, please point them out – I would love to see it.
As to N2 and O2 – they are diatomic, and don’t have emission modes worth speaking (orders of magnitude less) of in the IR spectra, unlike CO2, H2O, and CH4 (basic spectroscopy). They emit much better in the visible and UV spectra when heated sufficiently. N2 and O2 don’t have the vibrational modes to emit IR.
10
Sphaerica, re 123
It depends on your definition of ‘forcing’. Since the IPCC includes changes in GHG’s as forcing, it must also consider changes in surface reflectivity and changes in solar power as forcing. The N hemisphere winter snow pack substantially increases the reflectivity of the planet, but since the snow belt in the S hemisphere is over water, this effect is much smaller there.
There is also a significant difference in solar power between perihelion and aphelion, on the order of 20 W/m^2 integrated across the surface. This represents a post albedo difference in global average temperature of about 3C. Interestingly enough, perihelion coincides with maximum N hemisphere reflectivity, so that instead of the planet being 3C warmer, it’s about 4C cooler instead. Frequently, the difference between perihelion and aphelion is obscured when solar power is reported as AU normalized values.
Yes, you are correct that collisions of O2/N2 with the surface imparts energy to the surface. All this means is that radiative power is being traded off for non radiative power, but there is no fundamental change to the overall balance constraints.
So, what you seem to be saying is that large changes in forcing are adapted to quickly, while small changes are not? Both are subject to the same time constants which we can measure as the delay between min/max solar radiance and min/max temperature, which is about 6-8 weeks. BTW, after 5 time constants, more than 99% of the expected change to a perturbation will have already occurred, independent of the magnitude of that perturbation.
10
KR, re 124
The O2 and N2 emit a Planck spectrum of BB radiation, whose magnitude is proportional to T^4, as given by Stefan-Boltzmann. This is the primary source of radiation leaving the planet which is not otherwise passing through the transparent atmospheric window. The mechanism is via Faraday’s Law (the third of Maxwell’s equations). This says that a changing E-field manifests a changing B-field which in turn manifests a changing E-field 1 period later in space and time, whereas, the cycle repeats.
Atoms and molecules have a net negative charge in the near field since the electrons are closer than the nucleus. As molecules whiz past each other in close proximity, these moving charges interact to create time varying E-fields which are converting the kinetic energy of motion into EM energy and the hot atoms and molecules gradually slow down as they loose kinetic energy and cool. Many seem confused about the difference between radiation from an energized GHG molecule and BB radiation from a ground state, yet still warm, gas. For example, the difference between a CO2 laser and the heated O2/N2 of our atmosphere. The first emits EM energy at very specific frequencies, while the second emits a broad band Planck distribution with absorption gaps. The greenhouse effect basically converts narrow band absorption into broad band emission.
If you have any doubts that a heated gas radiates BB energy, consider what I said in #105,
10
co2isnotevil,
Your 20 W/m2 number seems far too high for the perihelion/aphelion difference. Do you have a cite?
I’m actually unsure at all what you mean by this, particularly the word “adapted”.
Specifically:
There is minimal change in forcing as a result of the seasons, and in any event this forcing swings back regularly (obviously).
The change in forcing as a result of CO2 is small on a per diem basis, but continuous and relentless.
The system does not adapt/adjust/absorb/account for anything that fast.
The noise in the system, in the short term ( 15 years) shows clear warming at a slower rate than expected, but this is not to me a sign that climate sensitivity is in fact low, when so many other lines of evidence point to a higher range. It implies that sensitivity is still about 2.8˚C/CO2 doubling, or higher, and that despite the fact that CO2 levels are increasing dramatically faster than any (known) time in the planet’s history, the temperature of the system cannot respond that quickly.
It is in the realm of possibility that the lack of rapid warming points to a lower climate sensitivity, but so much evidence refutes this hypothesis that I’m not about to hang my hat on it and end the thought process there.
10
Look at the TSI data here. It’s min at aphelion is about 1316 W/m^2 and the max at perihelion is about 1407 W/m&2, for a total difference of 91 W/m^2. A quarter of this (to account for the Earths surface area) is 22.75 W/m^2. You get the same values when you consider the relative difference in the distance from the Sun at the orbital extents and that solar energy drops off as R^2.
http://lasp.colorado.edu/sorce/data/tsi_data.htm
This is the only place I’ve found unnormalized data. All of the solar radiance data on the NASA site is AU normalized, which effectively cancels out the orbital differences.
10
co2isnotevil,
Thank you. I hadn’t realized the difference was so great, or that the TSI numbers usually reported are AU normalized for the sake of comparing solar output rather than actual “input” into the earth-climate system.
10
Bob,
Yes, NASA seems to hide this little fact, but their data covers a longer period. I’ve asked for unnormalized data on their web site, but is has never shown up, so I must undo the AU normalization for times not available in the SORCE data set. You’re not the first person to have been misled by this little subversion.
Now, consider that the global reflectivity (surface+cloud weighted by cloud coverage) at perihelion is about 0.3 while at aphelion, it’s about 0.27, the post albedo power at perihelion is (1-.3)*1407/4 = 246 W/m^2, while the post albedo power at ahpelion is (1-.27)*1316/4 = 240 W/m^2, so the net effect on the surface, owing to the changing reflectivity is close to zero. The reflectivity data was calculated from gridded data from isccp.giss.nasa.gov.
Nonetheless, there’s still a 3C difference in global temperature. This arises owing to the relative asymmetries in the response between the 2 hemispheres.
10
Hi KR,
Thanks for the response in 119 although you did not answer my question may be it was the way i asked it so i will use your analogy of a boiling pot.
If we imagine the climate before we added CO2 you could say we had a pot of cold water on a stove with the element turned off. The water representing the atmosphere and the element representing the heat supplied by CO2, as both are stable the climate is in equilibrium.
Ignoring feed backs for a moment if we add a little CO2 it would be like turning the element on from zero to one the element warms a little and in time so does the water (lag) until the water (atmosphere) reaches equilibrium.
If we add a little more CO2 (turn element from one to two) we add more heat and after a lag the water (atmosphere) warms until it reaches equilibrium.
Of course the climate works a little different because of feed backs and the theory (Latest version from the IPCC) tells us there are only +ve feed backs to increasing CO2 and this is proven by the fact that we are told the only way to stop AGW is to reduce our CO2 emissions.
So back to the pot, if the water is cold and the element is off the climate is stable, we add a little bit of CO2 by turning the element from zero to one and the water or atmosphere warms in response but it cannot reach equilibrium because the intial warming (forcing from CO2) generates more water vapour or in effect increases the heat supplied by the element without turning it from one to two. This additional heat from WV then raises the temp of the atmosphere (or water in our analogy) which in turn raises CO2, methane and lowers albedo.
All these feed backs are positive and in effect increase the heat supplied by our element without turning it up from one to two. The only way the water temp in the pot can reach equilibrium as you say is if a -ve feed back mechanism starts to act.
Therefore if as you say the climate will reach equilibrium it must be due to a -ve feed back can you tell me what it is?
Of course if my analogy is incorrect and equilibrium can be reach without a -ve feed back then can you please or anyone else for that matter explain where i have gone wrong.
Regards
Crakar
10
Bob,
Now consider what happens when perihelion and aphelion are reversed. The post albedo power at perihelion is (1-.27)*1407/4 = 257 W/m^2 and at aphelion it’s (1-.3)*1316/4 = 230 W/m^2 and the 22.75 W/m^2 of pre-albedo difference is amplified into 27 W/m^2 of post-albedo difference! This will result in much more seasonal variability in our climate. Part of our climates relative stability is due to the current alignment of perihelion with maximum reflectivity.
You should also take note that most climate models are driven with AU normalized solar data and as such, owing to the dramatic asymmetries between hemispheres and how this changes with orbit and axis changes, they are unsuitable for modeling long term effects, moreover; the effects of hemispheric asymmetry, relative to incident solar power, never seems to be considered in any GCM while it’s the largest ‘forcing’ variability that exists. Ignoring this is why there is so much emphasis on coercing CO2 and the magic of the enhanced greenhouse effect to provide the answer.
10
cohenite,
This is categorically untrue, and if it were true, the temperature of the planet would be a at least 20˚C cooler. This argument has been roundly debunked in many ways, and if you feel wedded to it, you should take the time to research it more thoroughly. I won’t spend time arguing it.
No, they don’t. Graphs like JunkScience, with selectively drawn “trend lines” are not reliable. I know you won’t accept that, so I won’t belabor the point, but anyone can post anything on the Internet. The fact that you found a graph that says what you want it to say doesn’t make it true. Anyone who wishes can research the issue further, decide what sources are reputable, and decide for themselves.
I would remind you, however, that due to the large amount of noise in the system, one needs 30 years or more to evaluate a trend. Your presentation of the data by breaking it into small chunks is exactly the wrong thing to do.
But how much, specifically, exactly how much, is important.
Using co2isnotevil’s own atmospheric simulation numbers, emissions from CO2 outweighs O2 by a factor of about 10,485 to 1, and that’s at a 280 ppm that’s even below the traditionally accepted pre-industrial (i.e. “normal”) levels of 285 ppm. H2O outweighs O2 by a factor of about 22,033 to one.
co2isnotevil’s numbers take that into account. Even when making up 99% of the atmosphere, look again. 10,000 to 1 and 20,000 to 1.
Again, actual numbers matter. One can’t just say it seems like there should be more, and it seems like there’s not, so it seems like there’s nothing wrong. The planet is huge. The oceans and atmosphere are huge. The amount of energy involved is huge. The time frames are very, very long.
If you want to make this sort of argument, you need to run the actual numbers (total energy in the system, total change, total expected distribution, total expected effect per storm, etc.).
But you also need a much longer time frame. You cannot drawn this sort of conclusion in the current time frame (1979 to the present).
10
KR@124:
http://www.ncdc.noaa.gov/teleconnections/enso/indicators/olr.php?num_months=12&view=View#num_months_form
Lindzen and Choi 2009 and 2010 and Knox and Douglass 2010 all provide good discussions of OLR variation and its significance for climate sensitivity.
10
Bob 133,
You are confusion absorption with emission. The O2 in the atmosphere primarily radiates a BB spectrum power as a consequence of it’s temperature. It’s line based emissions are even smaller than it’s line based absorption, since most of it’s absorbed energy will be distributed to the other molecules in the atmosphere.
10
co2isnotevil,
I don’t think NASA is hiding anything, or committing any subversion. Quite to the contrary, climate numbers commonly show what is relevant to most people, which is changes in AU normalized TSI over time, as it relates to the argument that the sun is getting warmer or cooler. The fact that there is a seasonal variation of 20 W/m2 surprised me, but does not affect my understanding of climate in any earth shattering way. Certainly, the 3˚C seasonal variation in global temperature is clear in the satellite record, and not particularly meaningful.
I find this beyond impossible to believe. Do you have a cite for this? Why hasn’t a single climate scientist, or even grad student, seized on this to make a name for himself, and create a better model? How can they possibly get anything in the models approaching an accurate simulation of the seasons without using proper earth TSI.
Again, you need a cite for this. As a statement, by itself, it’s unpalatable.
Please, at least in discussions with me, avoid this sort of statement. If you believe it that’s fine, but to me this sort of conspiracy theorizing suggests someone who is himself approaching the problem with an agenda of his own. It diminishes my trust in anything else you might present. You cannot possibly know something like this, so it is an unfounded assumption.
10
co2isnotevil,
Thanks, sorry… I only read your post over there quickly, and thought it was final TOA emissions, not cumulative absorptions. I’m too tired, and so was in too much of a hurry to find the numbers I was looking for.
10
Wikipedia says the range is 1,413 – 1,321 W/m^2 for perihelion-aphelion:
10
“http://en.wikipedia.org/wiki/Sunlight#Sunlight_intensity_in_the_Solar_System”>
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Sphaerica:
Pot-Kettle mate… the CAGW sites are far more septic than this one. Add the fact that both sides are equally accepted and free from moderation here, as opposed to sites like RC where polite but difficult questions contrary to their belief system are moderated out of existence.
Were the tables turned and this was the equivalent of RC your posts would never make it past the moderator. That’s a fact – I know from first-hand experience at RC as do many others here.
As for your comment that it is mostly politics discussed here… don’t you realise that is what “climate science” has become? You are way behind the learning curve if you haven’t grasped that fact. I don’t have a problem accepting any science that is empirically proven… I have a problem with CAGW forecasts made from models which don’t accurately represent the climate system, let alone the tenuous assumptions made within those models.
I have worked in academia and have an accute awareness about the eagerness some have to attract research funding and the the things they will do to obtain it.
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crakar24 @ 131 – A positive feedback doesn’t necessarily result in a run-away situation. It depends on the gain.
The general equation for a feedback is:
V = Delta/(1 – gain), where Delta si the initial forcing, V is the final value, and gain the gain of the system.
This works for positive and negative gains. You can see this by putting together an Excel worksheet – set the first row to your Delta, set each row to the previous cell plus previous times the gain [A1 = A2 + A2 * gain], and after a few lines (10 or so) it’s going to stabilize at some value if the absolute value of the gain is < 1.
Physical systems tend to have gains < 1.0 – otherwise they would require infinite energy!
Given an initial delta of 1.0, a gain of -0.75 (negative) will result in a final value of 0.25, damping the input. A positive gain of 0.75 will result in a final value of 4.0, amplifying the input.
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cohenite @ 134 – I haven’t been able to find Lindzen and Choi 2010. Their 2009 article (which I have read) appears to still be limited to +/- 20 degrees of latitude – the major criticisms of their initial paper were based on the fact that energy flows in/out of the tropics to the sub-tropics were orders of magnitude larger than the imbalances they discuss. Global energies require looking at global data, and they don’t. Given that they haven’t addressed the major criticism, I don’t feel that they have advanced their case.
I cannot find a Knox and Douglas paper from 2010.
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Sphaerica@133; a few points:
1 Saturation: it is true there are lots of weak lines on the wings of the CO2 band at 667 cm-1 and as the concentration increases, they start to become important and the width of the band increases. But the energy at this band width is lower than the peak at 14.7mu; and that band will be saturated before the absorption spreads to the wings; the weaker wings will also be subject to Beers Lambert law which means there will remain a logarithmic decline; the log decline is well described here:
http://wattsupwiththat.com/2010/03/08/the-logarithmic-effect-of-carbon-dioxide/#more-17114
2 But is the log effect actually a log decline at all? The point is that a log limit produces an asymptotic ‘limit’ which means that while there will always be a decreasing but still extant forcing through increases in CO2 there will not be a runnaway. A description of a logarithmic increase is y=a+blnx; this is unbounded and will produce a runnaway situation; alternatively, an exponential decaying in an increasing form is shown by y=C(1-e-kt),k>0, which is bounded. So perhaps it would be better to express the declining effect of increasing amounts of CO2 as an exponential decaying one rather than a log one.
3 Back in the real world subject to and defined by observations and statistical analysis Miskolczi shows that the observed climate sensitivity of increases in CO2 is 0; Beenstock shows that CO2 does not add to warming unless it is increasing exponentially, which is consistent with an exponential decaying form. These anaylses show that there is effective saturation for CO2.
4 The Junkscience graph was not the primary graph I used to prove there had not been Stratospheric cooling consistent with AGW, the AMSU satellite graphs were. A typical misrepresentation of AGW acolytes. As is the complete hypocrisy of this statement:
“But you also need a much longer time frame. You cannot drawn this sort of conclusion in the current time frame (1979 to the present).”
Tell that to disgraceful ‘scientists’ pushing AGW and who are quite happy to use disasters like the QLD floods and VIC bushfires to peddle their egregious nonsense. Like you they also speak in dulcet, patronising tones.
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Lindzen and Choi 2010:
http://www.legnostorto.com/allegati/Lindzen_Choi_ERBE_JGR_v4.pdf
Knox and Douglass 2010:
http://www.pas.rochester.edu/~douglass/papers/KD_InPress_final.pdf
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Sorry i still dont understand. If we accept the hockey stick and all of its implications we must also accept that the Earth’s climate has been very stable, this implies that we either have no feed backs or we have feed backs working in equal but opposing directions. Now however we are adding CO2 to the system which is causing the temps to rise and as Hanson has pointed out we are about to or may well have indeed already crossed a rubicon (tipping point).
I dont mean to be rude but do you understand the difference between gain and feed back? Here is my understanding of the two terms.
Gain:
The input to a system is amplified or reduced to effect the output, if we want to discuss CO2 effects on climate WITHOUT FEED BACKS then this is a good example.
Example (1) being the input, (2 & 3) being changes in gain (CO2).
1 X 2 = 2
1 X 3 = 3
In the above example the input remains the same but the gain has been increased which changes the output.
Feed backs:
Feed backs work in conjunction with the gain, using the above example again.
1 X 2 = 2
3 X 2 = 6
9 X 2 = 18
In the above example the gain (CO2) has remained the same but the out put is feed back to the input, of course with AGW we get a double whammy as the gain (CO2)is also increasing which must surely increase the magnitude of the feed back.
So to cut a long story short if we consider the preindustrial temp to be a steady state and we then induce a small gain via CO2 the temp will naturally go up however this will cause a larger increase in temp via WV/methane/albedo etc. This increase in the (output) temp will feed back into the (input) overall temp.
This will cause CO2 to increase further (the gain of the system will increase) causing more warming and the +ve feed back loop will continue as Hansen predicted.
The only this never ending increase in temp can be stopped is if you break the loop or introduce a -ve feed back, as it is impossible to break the loop then it must be a -ve feed back that brings equilibrium or even decline.
So what is this -ve feed back?
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Bob in 136,
What i find staggering is that you blindly accept the Earth being treated as a black body in model calculations but find the idea that modellers normalize AU out of sheer laziness unpalatable.
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crakar24 @ 143 – The “feedback” of 2-4.5C quoted by the IPCC represents a gain on initial CO2 forcings. It’s really the same thing presented in two different ways.
Either way, a gain of <1.0 means no run-away feedback.
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Sphaerica (Bob): says
January 14th, 2011 at 3:42 am
Lets be clear Bob. SW from the sun is invisible to GHGs. It is only the LW upwelling from the surface that GHGs interact with, correct?
Therefore, your body would be analogous to the surface emitting LW, and the blanket analogous to GHGs. (an analogy you used)
My experiment is valid.
Now I realise you’re trying to respond to numerous commentors here so I’ll take it that that confused you in responding to me. But that’s OK, you can try tonight when you go to bed, I’ve got time, I’ll wait.
Let me know how you go getting the T to 73 degrees.
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cohenite @ 142 – Lindzen and Choi 2010 as you linked (thank you, very helpful) address satellite precession, and appear to use more uniform (reasonable) time intervals for their sensitivity calculations. However, they still do not consider sub-tropic heat transport. That was one of the major criticisms of their previous work (along with selecting time intervals showing a low sensitivity, where there was enough freedom and reason to choose other intervals with any sensitivity you wanted from the data), and if they haven’t addressed it, they still haven’t made their point.
—
Knox and Douglass 2010 are using 2003-2008, six years, to determine their warming parameters. Given the noise inherent in measurements and ocean temps, this isn’t reasonable – you need 20-30 years of data, not 6. This is cherry-picking, choosing a subsection of a noisy data set and attempting to state long term trends from it. Look at the actual data, and be honest – is that long enough given the noise in the signal to make a determination? I’m saddened to see them performing such poor science.
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cohenite @ 142 – To expand on my comments about Knox and Douglas – if I were to choose 1965-1970 from the sea surface temps, I would get a huge warming. If I choose 1960-1965, I would get a huge cooling. Six years is far too short a time frame to get trends with that much climate variation.
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Baa Humbug,
I’ll respond to yours for now… not to others at the moment, because I’m exhausted.
But no, the whole transparency to various wavelengths thing has to be cut out of the equation, only because there’s no way to simulate it in the body/blanket experiment.
To put it another way, the simple model we are trying to experimentally prove/disprove is:
1) Inbound visible radiation from the sun heats the surface (atmosphere transparent to this).
2) Outbound infrared radiation from the surface tries to make it out into space.
3) The atmosphere does (or does not) intercept this radiation, and warm both the atmosphere and the surface as a result.
Your blanket experiment is fine for proving the second law of thermodynamics, and proving that a colder body (the room or the blanket) cannot warm a warmer body (the person), blanket or no blanket. It models elements 2 and 3, but not element 1.
But it does nothing to prove whether or not a body which is under constant inbound radiation can achieve a higher warmth with an atmosphere with a different composition. To do so, you must devise an experiment which includes all three attributes. The relative transparencies are not strictly necessary, but you are right… a mere heat lamp will heat the blanket from the outside, so it is inadequate.
If you can devise an appropriate experiment, we can discuss it. If not, we’ll just have to accept each other’s positions, and each walk away shaking our heads and grumbling in disgust at the other’s obstinance and inability to see what’s as plain as the sun in the sky.
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No. It’s easy to model as a blanket with holes, where the percentage area of the holes is equal to the atmospheric transparency.
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KR, you misunderstand both the Lindzen and Knox papers. L&C acknowledged criticism of their first paper which found tropical net increases in OLR which indicated much lower climate sensitivity than found by the GCMs; they then say this:
“We argue that feedbacks are largely concentrated in the tropics and extend the effect of these feedbacks to the global climate. We again find that the outgoing radiation resulting from SST fluctuations exceeds the zero-feedback fluxes thus implying negative feedback. In contrast to this, the calculated outgoing radiation fluxes from 11 atmospheric GCMs forced by the observed SST are less than the zero-feedback fluxes consistent with the positive feedbacks that characterize these models. The observational analysis implies that the models are exaggerating climate sensitivity.”
L&C redid their first paper on the basis of the criticism they received which came mainly from Trenberth; Trenberth’s critique concentrated on the time period of ERBE data L&C had selected to interpret whether there was net OLR; in their 2nd paper L&C addressed that and adjusted their time period and method of calculation so that it conformed to the substantial criticism of Trenberth. It is important to note that Trenberth shares L&C’s conclusion about OLR:
http://www.agu.org/pubs/crossref/2009/2009GL037527.shtml
Lindzen’s paper is about climate sensitivity as measured by OLR and they do consider the heat movements from and to the tropics; their 2010 conclusions are essentially the same as the 2009 ones.
Likewise Knox and Douglass are measuring climate sensitivity and enunciating a measurement of that based on OHC; the short time frame is irrelevant although one of the primary purposes of the Knox paper was to disavow the findings of the previous Lyman paper which found “a robust global warming trend of 0.63 ± 0.28 W/m2 for Earth during 1993–2008, calculated from ocean heat content anomaly (OHC) data.” Knox’s findings specifically contradict that finding. The second purpose of Knox was to address the controversial jump in OHC which occurred during the transition to the ARGO bouys in 2002-2003; that jump is depicted here:
http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/index.html
David Stockwell did a statistical analysis of the probability of such a large step up in the OHC occurring as the jump depicts; it is impossible:
http://landshape.org/enm/possible-error-in-ohc/#more-3180
What this means is that OHC before 2003 is essentially unreliable; Knox and Douglass confirmed this by showing a correlation between OHC, Fohc, and OLR, Ftoa; before 2003, the correlation between Fohc and Ftoa was poor, after 2003 it is good. Knox and Douglass is a groundbreaking paper, if one has the wit to appreciate that.
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cohenite @ 153 – Lindzen and Choi have been addressed in Murphy 2010 and Chung et al 2010. Murphy finds their limitation to the tropics only a failure due to the magnitude of sub-tropic exchanges (which they appear to repeat in the 2010 paper), and Chung likewise demonstrates that a tropic-only view is misleading compared to global data.
Knox and Douglas 2010 are only looking at six years of data. Have you looked at the sea surface data? I don’t care what six year interval you look at, that’s too short a time period (either before or after the Argo changeover, which as you point out may indeed have an effect on long term anomaly) to make a statistically valid trend statement.
The pre-Argo data is, in my mind, questionable in terms of absolute offset (the data was not well calibrated), but still shows considerable variation over a year-to-year basis even within periods of consistent sampling.
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Sphaerica (Bob) @ 151:
As near as I can tell, you hold that by changing one component of the system, the laws of nature that once dictate how the system will behave are negated and the system will behave in a totally arbitrary manner. Just so you clear on the point, ALL the laws of nature apply at ALL times in ALL circumstances no matter how convenient it would be that they not. Changing one component of a system does change the system but not the effectivity of the laws of nature. Hopefully, I am misunderstanding you but I fear not. My most benevolent interpretation is that you are failing to hold to the context that we are discussing the behavior of reality and not your fantasy how ever elegant it might be.
A specific question:
Are you saying in item 3 that the fact of the atmosphere intercepting this externally sourced radiation causes and additional warming of BOTH the atmosphere and the surface beyond that expected by the incident radiation alone?
I will agree that the interception of energy by the atmosphere will warm the ATMOSPHERE but how can that warm the atmosphere still more beyond that done by the intercepted energy? Least you forget, heat is energy. For the temperature of a material to be increased, the energy content of that material must be increased. The simple act of absorbing energy cannot warm the substance beyond the amount caused by that absorbed energy. To say otherwise is to entertain a violation of the first law of thermodynamics. THAT is one of many laws you cannot break! It applies no matter what change you make in the system.
A follow on question:
How can a locally warmed unconstrained gas of any molecular specie warm the earth’s surface? The real gas laws require the warmed gas to expand. In that process, it cools. Under the influence of gravity, the laws of buoyancy requires that that expanded gas will rise rather than descend to the surface. That ascent carries the heat in the wrong direction to warm the surface. The hotter the gas the more the expansion and the faster the assent. This is known as convection which, by the way, swamps any slight transfer of radiative energy from hot gas to the earth’s surface. It is also one of the more powerful mechanisms by which the heat contained within the surface is transported away from the surface.
In any event, the air earth couple cannot be heated BEYOND the amount of energy intercepted less the energy lost would provide. This is because heat is one form of energy. All you are doing in the proposed experiment is rearranging, transporting, and/or transforming the energy incident on the system. By the first law of thermodynamics, you cannot create energy in your system. Anything that happens happens BECAUSE of the original incoming energy.
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KR; I’ll write this in braille since you are obviously blind; in their 2nd paper L&C declare their intentions in addressing the criticisms of their 2009 paper by Trenberth, Murphy, Soden and Martha the cleaning lady; they say:
“We argue that feedbacks are largely concentrated in the tropics and extend the effect of these feedbacks to the global climate.”
The end.
And in respect of Knox and Douglass I will SHOUT, since your are obviously deaf as well; the term of the period is irrelevant to the principle they are establishing which is a correlation between Fohc and Ftoa; there was none before 2003 which should indicate to a reasonably sensed person that the measurements of OHC were done by blind Freddy and Daffy the deaf duck; L&C’s analysis shows a 6 year correlation; they are not measuring climate but verifying a measure of climate sensitivity; 6 years of replication of their hypothesis; give us an equivalent correlation with any aspect of AGW. And good luck with the new glasses and hearing aid.
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George, you have said several times in responses here words to the effect “The O2 and N2 emit a Planck spectrum of BB radiation, whose magnitude is proportional to T^4, as given by Stefan-Boltzmann. This is the primary source of radiation leaving the planet which is not otherwise passing through the transparent atmospheric window.” This is simply not true. O2 and N2 have essentially emissivity in the thermal IR and thus they do not emit. If they did, then they would also be absorbing in which case they would be green house gases themselves.
I can say this from very personaly and practical experience. Of late I have been working with air plasmas. The temperature of these is beteen 5000K and 6000K ie: about the temperature of the surface of the sun. If O2 and N2 emitted according to Planks law with a substantial emissivity they would be so bright one had better be wearing welding goggles. In fact the hot plasma is barely luminous. It glows a pale green, visible in the dark but barely visible in normal room light. Thus no significant visible emisison to speak of despite the visible being right in the middle of the emission band for an object of that temperature. Much more significant however – and this is somethng most people have very great difficulty accepting until they try it for themselves – one can put a finger 1 centimeter from the gas stream (which is at near 6000K) and you feel nothing at all. I don’t mean you can manage to keep your finger there, I mean you could not tell from the heat radiating onto your finger whether the plasam was going or not. In fact, there is so little indication its positively dangerous because close that 1 cm gap and actually enter the plasma stream and its instant 3rd degree burns if not worse.
This is not some experiment I tried years ago with distorted memory – its something I last tried last week!
As a comparison, inagine holding your finger 1 cm from an operating radiator bar element, how long could you hold it there before being burnt to a crisp and the radiator element is at less than 1000C compared to the plasma 5-6 time hotter.
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Sphaerica (Bob) and KR, thanks for all the posts. Very informative. Its pretty weird when all you need to do to find the interesting posts is to look for the ones with the most thumbs down!
BTW, co2isnotevil and cohenite, keep fighting the good fight. Its a thankless job but someone has to do it…..
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There is no point arguing the nuances of something that doesn’t actually exist – namely the mythical Greenhouse effect. Maybe the physicists should stop thinking in terms of 19th century physics and talk to some spectroscopic chemists so they can be set straight.
Unconfined gases (eg the atmosphere) cannot be heated by radiation – period. End of story.
The atmosphere can only heated indirectly by convection and conduction. The main method of heat transfer is by the evaporation and condensation of water vapour.
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Admittedly, I’m not following this debate, so feel free to ignore me. However I think that the following statement is a misconception of what feedbacks are and do:
Use a bicycle as an analogy:
1) A bicycle remains upright because the rider applies continual negative feedback to balance errors: If the bicycle tilts right, the rider moves the handlebars to make it tilt left, and vice-versa. Thus, any incipient tilt is rapidly corrected. Negative feedback creates dynamic stability.
2) If the rider were so careless as to apply positive feedback (moving the handlebars so as to increase the incipient unbalance) he would rapidly go down. Positive feedback creates instability.
3) If the rider never moved the handlebars, he would still go down (but not as fast as in #2), because incipient unbalance would not be corrected and would continue until the bike hit the ground. Zero feedback creates a system that drifts, not one that is stable.
If the bike rider alternately applied positive and negative feedback, this might create an entertaining circus act, but would not be stable.
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cohenite @ 156 – I prefer data and statistical significance to insults, quite frankly.
I’ve read the L&C papers, and they have not addressed energy interchange with the sub-tropics – again. Since those exchanges (plus and minus) are an order of magnitude larger than the effects they are emphasizing, their limited region analysis gives invalid results (Murphy, as I linked to). Running the same kind of analysis on a global basis (as Chung demonstrates) gives very different results.
As to Knox and Douglas – six years is too short a time period to make conclusions from the noisy data; they are cherry-picking. fOHC (change in ocean heat content) is not measured as well as anyone would like to see – the Argo array doesn’t go terribly deep, and we have a poor grasp on the vertical currents redistributing energy. I would give it a few more years of data before making _any_ claims about trend changes. I could as well pick any three days in June, depending on the weather, and run around screaming “Ice Age” or “Heat Death” depending on that short trend…
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crakar24,
I haven’t read all of your posts, but I think the problem that you are having with feedbacks (in any direction) is that you are thinking linearly. For instance, you are assuming that if there is a positive feedback, that feedback must always be of the same scale, and so they would lead to a runaway effect.
This is not the case. As the system builds, each feedback is only a fraction of the previous, leading to a converging series, like on where each subsequent feedback is one half of the previous:
1 + 1/2 + 1/2(1/2) + 1/2(1/2(1/2)) + 1/2(1/2(1/2(1/2))) + . . .
which is
1 + 1/2 + 1/4 + 1/8 + 1/16 + . . .
which converges towards 2.
No negative feedback is needed to forestall a runaway effect. An initial forcing of 1/2, with a feedback of 1/2 of the previous value, leads to a doubling of the initial value.
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Lionell Griffith – I understand how the greenhouse effect might sound like hooey, but I’d like to give you an analogy I find helpful.
This is an analogy – not perfect, but I think it includes some aspects of the climate system.
—
Imagine a large tank (the Earth). Water pours in from a spout overhead (sunlight), and leaves through a pipe at the bottom (thermal radiation to space) at a rate dependent on the water level and pressure (energy in the climate, level analogous to temperature). Steady state, the same amount of water comes in as goes out.
Now some leaves partially clog the outlet (greenhouse gases) – the flow rate slows. Water backs up in the tank until the pressure is high enough to run as much water out as is coming in (temperature rise), and everything steadies out again. Until we throw more leaves in the tank, of course…
—
Space is at about 3K, the sun is around 5000K, the Earth is somewhere in-between. Where we are along that scale depends on how well we get rid of the incoming sunlight.
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Fun with feedbacks!
Fire up Excel. In the first row, enter “1”, “0.5”, and “1”, representing an initial value, a gain, and an increment/forcing.
Row two, enter “=A1+B1*C1”, “=B1”, “=B1*C1”
Copy row two, paste it down 20-30 lines. Now you can play with gains (positive and negative feedbacks) and various forcings. You’ll see the series asymtotically converge to some value.
Gains >=1 or <= -1 will be unstable; everything else converges. For a CO2 doubling estimated at 1.1C forcing, the 'gain' for the IPCC values of 2-4.5C change are between .65 and .8 or so. For L&C (1.1, essentially zero feedback), the gain would be 0.5 for the system.
The result comes out to delta = forcing/(1 – gain) at the end.
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Ack – My post at 164 is wrong! I dropped the first term.
Add a row 2, with “=A1+C1”, “=B1”, “=C1”, and that should fix the spreadsheet.
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Lionell,
Forgive the length of this comment, but I find the need to be absolutely thorough, so there is no misunderstanding. If need be, read this in chunks. I tried to keep it simple, even if long, but obviously I left out many details (for the sake of some nod to brevity), and so some things are still oversimplified. But I tried not to leave anything out that is relevant to this particular system (i.e. the heat source/body/blanket analogy required).
Your difficulty is that you are oversimplifying the system, treating all energy as one thing, immutable, transferable thing, like a single form of currency. There are many different energy currencies, and they can’t all be exchanged at all times for each other. There are rules. The energy exchange in the earth/atmosphere/space/sun system is like a cosmic game of rock/paper/scissors.
There are different types of energy: in our case, translational (movement), vibrational, and electromagnetic.
You must also understand that heat is not energy. Heat isn’t really anything. It doesn’t exist. Heat is a manifestation/measure of the kinetic (translational, vibrational, rotational) energy in a substance. In a gas, heat is a measure of the amount of kinetic energy (i.e. the molecules zipping around) in a volume. It is not a direct measurement of all of the energy in the gas… it excludes vibrational, rotational and other energies (such as the excited states of the electrons), but is a proxy for such energies, because of the theory of equipartition of energy (i.e. given enough of a substance, and enough time for it to reach equilibrium, the various forms of energy in the system will be distributed in predictable amounts, so the measure of temperature — the heat, meaning the translational energy in a gas — can be used to determine the actual total energy in the volume of a substance).
In a solid, heat is instead a measure of the vibrational energy of the component atoms. In a liquid, it’s a mixture of both. But heat is not a thing, and it’s not energy (any more than “color” is a thing… color is just the way your mind presents the fact that your eyes are detecting photons of a certain wavelength of light).
Within the system of the earth’s atmosphere, you have to take the different types of energy step by step.
First, the earth is bombarded continuously by electromagnetic radiation from the sun. This energy basically covers the entire spectrum, from gamma rays to X rays to UV to visible light to the infrared. Fortunately for us, the UV light is filtered by the stratosphere, where it causes conversions between O2 and ozone (O3), but does not get through… or else we’d all be dead.
The component molecules of the atmosphere (except for H2O), however, are transparent to visible light, so that pretty much passes through to the surface of the earth without heating the atmosphere.
The compounds on the surface of the earth, being far, far more complex than the molecules in the atmosphere, are not transparent to light. This is obviously so, since you can see through the air, but not through a rock or a tree.
This means that when the visible light (as well as the UV and infrared which makes it through the atmosphere) strikes a solid object, it is absorbed and warms that object (i.e. starts the molecules vibrating, which we measure and perceive as heat, but remember, heat doesn’t exists, it’s just a proxy for kinetic energy at the atomic/molecular level). This is why your face feels warm when hit by the light of the sun. It’s making the molecules in your skin vibrate as they absorb those photons.
This vibration doesn’t go on forever. Randomly, over time, the atoms/molecules will stop vibrating and “shoot off” a photon with a level of energy energy determined by the energy in the (now ending) vibration. This is always in the infrared area of the spectrum. It can go in any direction.
If it goes sideways or down, it just hits another object, and starts it vibrating. This is what you feel when you put your hand near the hot pavement and say “that’s warm.” The infrared light is hitting your hand, and starting the molecules in your skin vibrating, just as visible light did.
But if it gets up past the solid objects, it tries to pass through the atmosphere. That is where greenhouse gases come into play. O2 and N2, because of their molecular geometry (two connected atoms, like a dumbbell), cannot vibrate, than can only rotate and move. Greenhouse gases, with more complex geometries are able to vibrate (CO2 is like a dumbbell with a third, heavier ball in the center, while H2O is the same, but bent like a boomerang).
This means that if infrared light strikes an O2 or N2 molecule, it passes right through. Those molecules are transparent to infrared light of almost all frequencies.
But if it strikes a greenhouse gas molecule, and is of the correct wavelength (i.e. energy level), then it will be absorbed by that molecule and the molecule will begin to vibrate.
That molecule can now do one of two things with that energy. It can re-emit the photon, in the exact same wavelength, but in a random direction. Alternately, if it collides with another atom before it can do so, it will pass that vibrational energy on to whatever it strikes, making it either vibrate, spin, or move faster (or some combination thereof), depending on the geometry of the other molecule, and the collision.
Because there is so much O2 and N2 in the troposphere (i.e. the lower atmosphere), a collision is 1,000 times more likely than re-emission. So the heat that should have escaped into space is instead transferred to the atmosphere.
The O2 and N20 molecules themselves, however, will radiate the energy away only very, very, very slowly. With no vibrational modes, they can only do so by rotational energy, which is minimal. These molecules simply do not emit notable amounts of radiation. In the real world, such “cooling” is absolutely negligible.
So no you have energy from the sun being intercepted in the stratosphere (UV), or reaching the ground (visible and infrared) and warming it. You have the ground cooling (i.e. emitting infrared light), some of which escapes into space, and some of which is intercepted by greenhouse gases, then passed on to simpler, more prevalent gases, thus warming the atmosphere.
Beyond this, there are many other mechanisms. As you get higher in the atmosphere, the air is more rarefied. The molecules are further apart. This reduces the chance of collision, making the chance of emission more likely. Here the tables begin to turn, and there is an increasing chances that a “hot” O2 or N2 molecule will strike a greenhouse gas molecule, passing on some energy in a vibrational state, and that molecule will in turn get to emit that energy as infrared radiation — potentially out into space. So you reach a point where the planet is ultimately able to shed the accumulating heat.
At the same time, heat is constant transferred throughout the atmosphere through advection and convection. Hot air rises. As it rises it cools. Eventually, cool air can sink to be replaced by hot air. This obviously acts as a way to transport heat up into the atmosphere… but it still can only escape through some mechanism of radiation (see greenhouse gases).
Another important method of heat (i.e. energy transport) comes from water vapor. Water can evaporate (i.e. change from liquid to solid, meaning it attains enough translational energy to break it’s attraction to other water molecules and enter the atmosphere). It can rise. It is also among the strongest of greenhouse gases. So it is able to cool by emitting infrared radiation after it has risen high enough in the atmosphere for that radiation to escape into space.
Alternately, water vapor can condense on very small nuclei. The condensation of water requires cooling. Cooling means the heat (i.e. the vibrational and translational energy) must go somewhere. It does… to the surrounding atmosphere (primarily O2 and N2 molecules through collisions. In this way rising, moist air is able to transfer the heat to the atmosphere, as well as “keep some of it” and return to the surface as precipitation.
So you can see that the number and variety of mechanisms is wide, and it is necessary to understand them all. It is far too simplistic to think only in terms of “heat” going up and down, or infrared radiation shooting all around.
So, too, you should now see that any attempt to prove the application of the second law of thermodynamics in this system must recognize that not all energy (and not all heat) is equal and transferable. There are many different mechanisms for the transfer of energy, and they aren’t all equal and compatible. Its a giant, complex game of rock/paper/scissors. UV light heats the stratosphere. Visible light through the atmosphere heat the ground. Infrared light heats greenhouse gases in the atmosphere. Greenhouse gases in the atmosphere heat other gases (through collisions). Water does all sorts of things, as does rising and sinking air.
The system is not that simple, and attempts to riddle out how greenhouse gases will affect the world through overly simplistic thinking is doomed to arrive at wrong conclusions.
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Lionell,
On rereading, I left out a point (but included many typos!).
Advection versus convection. Advection I described (the rising/sinking of air). Convection is the simple transfer of heat when two bodies are in contact (i.e. you put your hand on a hot plate). This obviously can also happen on earth… air that is in contact with the ground, or one body of air that is in contact with another.
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Sphaerica at 166: You must also understand that heat is not energy.
Wow! Tell that to the scientists and engineers who constructed industry and built a technological civilization over the past 150 plus years. I suggest you actually learn some basic science and thermodynamics before you begin shooting off your mouth on a science based blog.
See: https://www.msu.edu/~moorean4/TestSite/Adobe%20Worksheets/Adobe%20Worksheets/Unit%203%20WS/joulenotes.pdf
Also see: http://www.chemteam.info/Chem-History/Joule-Heat-1845.html
Until you can understand such a basic concept, there is no point discussing your squid like flood of words.
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Michael,
When the spectral characteristics of the Earth’s emitted power spectrum are examined from space, there are spectral gaps at all of the absorption/emission wavelengths. We can explain this as the power passing from the surface and clouds through the transparent regions of the atmosphere. Based on the size of the transparent window, not enough power passes through from the surface and cloud tops into space, in fact, only about 40% of the required power passes through and into space through this window.
If the 60% of the missing power was emitted from GHG’s in their absorption bands, which are the only places in the spectrum they emit, why are there absorption gaps in the measured spectrum, instead of emission lines?
You must agree that the missing power is still passing through the transparent regions, just not originating from the surface or cloud tops. Where else can it originate from but from the atmosphere itself? The only other answer is that HITRAN line data is horribly wrong and the atmosphere has a much larger transparent window.
Consider the Sun. The photons that arrive on the Earth are not the direct result of fusion, but the result if BB radiation from the heated gas at the Sun’s surface. This is why the spectrum emitted by the Sun has a Planck spectrum (with a few gaps).
Consider clouds of gas in deep space. We can look at them in the IR and see the emitted spectrum, We can gage the temperature by the location of the peak in the distribution (by applying Wein’s Law) and we can tell what trace elements are present in the H2 clouds by examining the absorption gaps in the spectrum.
Consider a hypothetical, gravitationally bound ball of O2 and N2 at some temperature, T. If what you are saying is true, it would never cool and would be invisible because it’s not radiating any energy. If it was receiving energy from a star and contained a small amount of O3, it’s temperature would increase without bounds.
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Lionell,
Please read my post beyond the first sentences.
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Lionell,
Example: if you put the same amount of energy into the same volume and molality of two substances, one O2, the other H2O, they will have very different temperatures (different amounts of heat).
Same energy, different temperature.
Look up the term “specific heat.” See how it differs for different substances? It is a measure of how much energy required to heat different substances to the same temperature.
Heat is not energy. It is a proxy measure of energy, with the exact relationship being contingent upon the characteristics of the substance in question.
Until you can understand this — the manifestation of energy at the molecular, atomic and quantum levels — you cannot understand energy transfer in the earth-atmosphere-space system.
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Sphaerica at 170,
Why bother? You have demonstrated you don’t know what you are talking about.
As evidence see yourself at 167 where you demonstrate that you are confused about convection and conduction. Heat transfer by contact is conduction and not convection.
Advection is simply a more generic term for mass flow of a fluid in a specific direction by whatever means. Convection is the mass flow of a fluid due to mass density changes under the influence of gravity.
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Spherica at 171,
You continue to be confused about some very basic concepts necessary for discussion about climate physics. Heat and Temperature are NOT the same – not even close. Like I say, learn some basic physics and when you have, come back and lets discuss. Until then, have a nice day.
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cohenite – Ocean Heat Content – You might want to take a look at a recent paper, Lyman et al 2010, which is looking at the uncertainties in measuring ocean heat content.
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“…Here we examine several sources of uncertainty that contribute to differences among OHCA curves from 1993 to 2008, focusing on the difficulties of correcting biases in expendable bathythermograph (XBT) data. XBT data constitute the majority of the in situ measurements of upper-ocean heat content from 1967 to 2002, and we find that the uncertainty due to choice of XBT bias correction dominates among-method variability in OHCA curves during our 1993–2008 study period. Accounting for multiple sources of uncertainty, a composite of several OHCA curves using different XBT bias corrections still yields a statistically significant linear warming trend for 1993–2008 of 0.64 W m-2 (calculated for the Earth’s entire surface area), with a 90-per-cent confidence interval of 0.53–0.75 W m-2.”
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I’m sure that this is far from the last word on the subject, but I don’t think it’s justified to flatly state that the oceans have stopped warming.
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Lionell,
I never said heat and temperature were the same. I will admit to having misspoken about the terms advection/convection/conduction, however my lapse was not one of understanding, but merely terminology (I do not that often communicate about the distinction).
I would advise you to switch therapists, however. Those anger management classes aren’t working for you.
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Michael,
I have a question for you relative to your air plasmas. How are you measuring it’s temperature? Usually, this would be done by pointing an IR sensor at it to measure the emitted radiation.
Consider a light bulb, whose filament is glowing at 3000K. You can put your hand millimeters away from the bulb and it’s only slightly warm, yet when you look at the light bulb with an IR sensor, it’s glowing at a very high temperature.
Another interesting example is to use an IR camera to look at a person breathing. You can see their warm breath against a cold background.
It’s certainly well known that a high pressure gas is a BB, but what this really means is that a high pressure gas is a better BB, relative to absorbing energy. If heated by other means, for example, via GHG’s, even a low pressure gas radiates a Planck spectrum, for example, gas clouds in deep space.
So, when someone says that O2 or N2 is not a good black body, they mean that without help, it will not absorb radiation from the environment and thus will not emit this absorbed energy. In a strict sense, an ideal BB absorbs 100% of the incident radiation and then emits this as a Planck distribution. O2 and N2 can still emit a Planck distribution when heated by other means, even though in a strict sense, these gases are very poor black bodies.
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KR, the Lyman and Trenberth papers about increases in OHC are reviewed here:
http://www.thegwpf.org/the-observatory/1011-are-the-worlds-oceans-warming.html
The subsequent Knox paper was meant as a rebuttal of the Lyman methodology which was based on the proven to be defective pre-ARGO OHC measurements, an issue you avoid. About your alleged “cherry-picking” by Knox based on the short time period of their data they say this:
“There are issues associated with a “short-time”
segment of data, which are addressed.”
They address this issue by examining the basis of the Lyman paper’s concern with the post ARGO “flattening” [what a joke! it is not a flattening but a decline; such is the unwillingness of AGW proponents to admit the unadmissable] which Lyman blames on the interannual variations of the ARGO data; Lyman says: “These uncertainties are large enough that the interannual variations, such as the 2003–2008 flattening, are statistically meaningless.”; that is, Lyman blames the ARGO measurements, which are far more reliable and accurate than the pre-ARGO measurements for the ‘inconsistency’ of the post 2003 OHC values. How incredible is that!? But Knox plays Lyman’s game and removes the interannual variations, in effect deseasonalising the data, using 4 different methods; their result is cooling over the only reliable period of data.
Your claims about cherry-picking are baseless.
So to with L&C which you persist in accusing of taking a non-global approach and by restricting their attention to Tropical feedbacks negate their conclusions. YOU ARE WRONG. Equations 7a and 7b of the L&C 2010 paper specifically address this complaint by extending the feedback analysis globally. Your persistance in this baseless accusation is quite frankly dumb.
Furthermore the L&C paper looks at distinct tropical events such as ENSO and the feedbacks they generate as measured by OLR. There is some evidence that such feedbacks based on tropical events do not affect the heat flux from the tropics to other latitudes; “That would mean that the tropics handle themselves the extra heat coming from El Nino. In a sense, the tropics are a ‘closed system’ with respect to the extra heat emanating from El Nino.”
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cohenite @ 177 Lindzen and Choi 2010 explicitly states that in 7a and 7b, regarding a constant of “2” extending their results to the globe: “…the factor 2 results from the sharing of the tropical feedbacks over the globe following the methodology of Lindzen, Chou and Hou [2001]”, with more detail in Appendix 2.
I hate to state it so baldly, but this is simply handwaving, a geometric extension (scaling by area/insolation) with zero consideration for actual +/- sub-tropic energy exchanges. They have corrected nothing in this regard from their flawed 2001 paper.
Read Appendix 2, or better yet L&C 2001 (I have) – there’s no data, no measurement, just a couple of assertions and a geometric scaling.
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In regards to Knox et al (which I have also spent time reading carefully), they are using 2003-2008 data from Argo. That’s only six years of data.
I’ve pointed to the actual data, both the Argo the XBT values. Better yet, here’s the graph with more recent 2008/2009 data added in, which certainly doesn’t look like it’s declining to me. Given the year to year variation in both data sets, I will have to agree with Lyman that “These uncertainties are large enough that the interannual variations, such as the 2003–2008 flattening, are statistically meaningless.”
Seriously – given how varied the data is, can you honestly say that a six year period is sufficient for a trend??? 15, maybe, 20, certainly. I hold out hope that another 5-10 years of data will indicate that OHC has stopped accumulating, although given greenhouse gas physics that seems extremely unlikely.
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At this point I’m just going to have to disagree with you on the valuation of these various papers.
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I’m sorry KR, but I can’t let this crap go unanswered. In respect of L&C and the ‘defect’ of their lack of consideration of extra-tropical “energy exchanges”; in appendix 2 of the 2010 paper they say this:
“Appendix 2. Concentration of climate feedbacks in the tropics
Although, in principle, climate feedbacks may arise from any latitude, there are substantive reasons for supposing that they are, indeed, concentrated in the tropics. The most prominent model feedback is that due to water vapor, where it is commonly noted that models behave as though relative humidity were fixed. Pierrehumbert [2009] examined outgoing radiation as a function of surface temperature theoretically for atmospheres with constant relative humidity. His results are shown in Fig. 10.
We see that for extratropical conditions, outgoing radiation closely approximates the Planck black body radiation (leading to small feedback). However, for tropical conditions, increases in outgoing radiation are suppressed, implying substantial positive feedback. There are also good reasons to suppose that cloud feedbacks are largely confined to the tropics. In the extratropics, clouds are mostly stratiform clouds that are associated with ascending air while descending regions are cloud-free. Ascent and descent are largely determined by the large scale wave motions that dominate the meteorology of the extratropics, and for these waves, we expect approximately 50% cloud cover regardless of temperature. On the other hand, in the tropics,
upper level clouds, at least, are mostly determined by detrainment from cumulonimbus towers, and cloud coverage is observed to depend significantly on temperature [Rondanelli and Lindzen, 2008]. As noted by Lindzen et al. [2001], with feedbacks restricted to the tropics, their contribution to global sensitivity results from sharing the feedback fluxes with the extratropics. This leads to the factor of 2 in Eq. (6).”
These are cogent reasons for both concentrating on the tropics and limiting extrapolation of energy exchange with the extra-tropics to a factor of 2.
The 2001 paper does indeed explain this in further detail as does Lindzen’s reply to a comment on the 2001 paper here:
http://stephenschneider.stanford.edu/Publications/PDF_Papers/LindzenRebuttal2002.pdf
Here the specific issue of the “intrusion of extratropical non-convective systems” into the tropics is addressed; they say:
“Intrusion of extratropical systems versus latitude. If the iris effect depended primarily on
intrusion of extratropical non-convective systems, we would expect a noticeable reduction of the
effect when the poleward limit of the region considered was reduced – even if the extratropical
systems penetrated beyond 25° latitude. This is not what we find. This is illustrated in Figure 5, which shows the cloud-sea surface temperature (SST) relation as in Fig. 5a of LCH, except the
domain is confined to the latitudes lower than 25°. The result is similar to that of LCH. The
correlation coefficient is –0.301 for the region 30°S-30°N (not shown in the figures) and –0.348
for the region 25°S-25°N (Fig. 5). If the effect suggested by HM were of primary importance, we
would expect the correlation to decrease. Rather, the opposite is observed. This supports the view that we are looking at cirrus associated with convection rather than stratiform clouds associated with penetrating mid latitude systems. Incidentally, statistical analyses show that the negative correlation is highly significant (Bell et al., 2002).”
Neither the Murphy or Chung papers have negated this.
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Why would you expect an economist to be able to predict the outcome of forcing people to adopt a new and untested technology to replace existing and proven systems? The economist is no expert in the technology itself, and has no market data for the emerging economy they are supposedly predicting, and anyhow economic theory is all based around the principle of a free market.
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cohenite @ 179 – And yet Lindzen and Choi are still using a geometrically derived factor of 2 scaling to include all global effects? They have not addressed the major issues raised by the Murphy or Chung papers in any manner whatsoever.
I’ve gone through their 2001 paper in quite some detail. They state a lot of things (many without evidence or reference), dismiss all sub-tropic exchanges as zero, then use their geometric factor. Murphy and Chung both found that this method led to errors when using global data.
If you still find Lindzen and Choi acceptable, well, that’s your decision. I just cannot agree with it.
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KR; would you please elaborate on the errors found by Murphy and Chung in respect of climate sensitivity and OLR when they compared global data with the tropical specific data of L&C 2009?
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cohenite @ 182 – Well, to quote the Murphy abstract (sorry, I don’t believe there’s a free access version):
“Several papers have used correlations between outgoing radiation and surface temperature to estimate climate sensitivity via a linearized energy balance equation. A crucial assumption in such studies is the use of global averages to relate radiation and temperature data that are actually functions of space and time. Here it is shown that this assumption is important to understanding why transient and equilibrium climate feedbacks may differ. There are important limitations to derivations of climate sensitivity from correlations between radiation and temperature data. In particular, because of heat transport between regions, obtaining the equilibrium temperature change by multiplying the forcing by a climate sensitivity is valid only for a global domain. The analysis of Lindzen and Choi (2009) erroneously applies global concepts to a limited region. ….” (Emphasis added)
In short, multiplying the tropic numbers by a geometric constant (Lindzen 2001) gives a sensitivity value contradicted by global data due to energy exchange with the sub-tropics.
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Chung found, using nearly global data, that a positive feedback was indicated – and that tropic-only data does not provide enough data for a global sensitivity number.
Again, I can’t find a public access to the full text, my apologies. Geophysical Research Letters doesn’t push much out to public domain, wish they did.
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Yes, I only have the abstracts as well which is why I asked. Some points:
1 L&C do not seek an “equilibrium temperature”, they are concerned with short term measurements; they say: “Since our analysis of the data only demands relative instrumental stability over short periods, it is difficult to see what data problems might change our results significantly.”
2 L&C do not do this: “The analysis of Lindzen and Choi (2009) erroneously applies global concepts to a limited region. ….” L&C extrapolate from a regional effect, which is not disputed, to a global concept.
3 This, whether you or Murphy appreciates it, is a restatement of the one of the fundamental flaws of AGW: “There are important limitations to derivations of climate sensitivity from correlations between radiation and temperature data. In particular, because of heat transport between regions, obtaining the equilibrium temperature change by multiplying the forcing by a climate sensitivity is valid only for a global domain.” This is completely contradictory and this contradiction is demonstrated by these 2 papers:
http://pielkeclimatesci.files.wordpress.com/2009/10/r-321.pdf
http://www.uoguelph.ca/~rmckitri/research/globaltemp/GlobTemp.JNET.pdf
Both these papers show why a global average temperature [GAT] is unreliable and not a true measure of the Earth’s radiative balance. As you know the Essex et al paper was derided [but had no official peer reviewed rebuttal] when it appeared but has now been vindicated at such luminary blogs as SoD. The Pielke paper, on reflection, is just common sense with higher temperatures and radiative OLR effects having more impact than larger changes based in cooler regions. Both papers support L&C’s focus on the tropics; L&C’s factor of 2 could be more concise but is probably overgenerous; the correct way of calculating ERB is (A + B)^4 > A^4 + B^4; that is the radiative value based on Stefan Boltzman has to be calculated for each location rather than averaging all locations then applying SB to obtain a correlation between temperature and ERB.
4 Point 3 is why Murphy is wrong to say: “obtaining the equilibrium temperature change by multiplying the forcing by a climate sensitivity is valid only for a global domain.” Having said that I note that Murphy claims this: ” I also show that a simple, point-by-point regression of outgoing radiation against surface temperature gives better slope estimates than the interval method used by Lindzen and Choi (2009).” This would appear to be consistent with what I have described as the defect with the usual way of correlating ERB with GAT.
5 But the difference between an equilibrium climate sensitivity [ECS] and a transient one, a pillar of AGW, is problematic. An ECS relies on the unproven notion of stored heat; Beenstock has contradicted this idea and the lack of ocean warming at any level physically disavows it since the ocean is the only place such heat can be stored. Given the dominance of the tropics as a source of any storage heat L&C’s findings, even if pertinent to only the tropics, are a severe contradiction.
6 But L&C are not restricted to the tropics in 2010; they extrapolate to the globe; whether their method is as valid as Murphy’s would require Murphy’s paper to be read in full; it would also be interesting to see what sort of climate sensitivity figures Murphy obtained bearing in mind his reference to the false idea of ECS and transient climate sensitivity.
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It’s ironic that L&C’s low sensitivity is criticized for being derived from data covering more than 1/3 of the planet and extrapolating from there, while those who criticize, have no trouble accepting high sensitivity from extrapolated (homogenized) data representing less than 1% of the planet. It’s clear that the coverage is not the real issue, it’s the results they don’t like and complaining about the coverage is a disingenuous ploy to discredit L&C with the deluded hope of keeping a flawed hypothesis alive as it death appears imminent. I think it’s time to pull the plug and end it’s misery.
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“It’s ironic that L&C’s low sensitivity is criticized for being derived from data covering more than 1/3 of the planet and extrapolating from there,”; and as I have tried to explain that extrapolation is justified with cogent reasons.
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Just an aside. “Catastrophic” global warming comes from feedbacks, which are fairly arbitrarily set (set for tuning and reset for projections in the case of SO2).
Without feedbacks, the 1.2C increase is about the difference in average temperatures between Boston and New York City. Try it for cities of your own choice.
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Oh George, it looks as though the canonical value of 2XCO2 forcing of 3.7W/m2 will have to be adjusted in line with new values for TSI:
http://wattsupwiththat.com/2011/01/14/total-solar-irradiation-tsi-value-lower-in-2008/
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George; I think we need to look at a plot of Earth’s emission spectrum from space while discussing the issues you raise. I tried to include a plot in this comment but it appears the system does not accept images. I then tried to send the link to the source of the spectrum I used and surprisingly it has been removed (I wonder why). However after a great deal of looking around I found this link http://www.xylenepower.com/Emissivity.htm please download this and look at the graph for reference. I was going to give a detailed explanation of this graph but reading the first section I note that Charles Rhodes has already done so. What he does not say explicitly but does implicitly is that this plot was taken at a time of dense low cloud cover. The equivalent BB temperature between about 750 wavenumbers( 13.3microns) and 1250 wavenumbers (8 microns) is 270K or -3C reflecting cloud top temperature. Without the clouds this would be more like 290K (17C) reflecting the surface temperature. This indicates where the energy is coming from.
At the CO2 absorptiuon line between about 600 and 700 wavenumbers the emission temeprature is 215K matching that of the tropopause whcih again is where this radiation is coming from.
Now the area under the graph is the total emission to space. Just look at that portion between 750 and 1250 wavenumbers. Just by eye one can see its about half the total area which means half the energy is comng from cloud tops in a condition of complete cloud cover. Without cloud cover the emission temperature is that of the surface (significantly higher) and the surface emission to space is then far more than half the total. Since on average 1/3 of the surface is without cloud cover the average surface (plus cloud top) emission to space is well over half the total (in fact substantially more because some of the emission below 600 wavenumbers is also surface emission).
When he talks about emission from condensing water vapour, the emission is coming from the warm liquid water drops that are forming (ie: clouds). Liquid water is indeed close to a BB in the thermal IR.
To take up the issues in your comments 176. Firstly I am measuring the temperature by injecting some material which does emit at those temperatures (typically a metal salt which generates both atomic and ionic emission). By looking at the relative intensity of the atom and ion lines one can determine the temperature.
Your example of the light bulb is not valid. The filament is inside a galss envelope. The glass is a good absorber of infrared so it absorbs the energy radiated by the filament and warms up in consequence until it is emitting the same amount of energy as the filament. However since the glass area is far far larger than that of the filament, the energy density wil be far lower and the glass thus far cooler than the filament. Despite this, try putting your hand close to the glass envelope of a 100 watt lamp after it has been running for some time. The plasma I am talking about has an energy injection of well over 1000 watts and is far far smaller than the glass surface of a 100 watt incandescent bulb.
Your point about measuring the temperature of exhaled breath with an IR thermometer, sure but remember that exhaled breath contains very large amounts of water vapour and CO2 both of which are ghg and thus do emit in the thermal IR and in many cases this water vapour is condensing a short distance away from the body and the liquid water droplets are essentially BB radiators.
Your last comments in 176 do not make sense to me. Are you saying that N2 and O2 do not absorb radiant energy from the environment yet they do emit continuum radiation when heated by other means? If so, that contravenes the rule that emissivity and absorptivity at any given wavelength are always exactly equal. It can readily be shown that contravening this rule contravenes the second law of thermodynamics.
Sorry if all this sounds rather brief but the issues you raise are complex and to treat them in detail would invove an excessively long post both for me to type and for you and others to read.
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cohenite @184 – As I stated earlier, I’m going to continue to disagree with L&C based on a simple geometric scaling, which certainly doesn’t take into effect measured things like Arctic Amplification and energy exchanges 10x larger than their imbalance measures.
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On a different topic, however – transient versus equilibrium response. It’s always been my understanding that the equilibrium response is not due to energy being stored (present, just not showing), but rather energy accumulating. To return to the “pot on the stove” analogy, a small amount of energy imbalance will take quite some time to warm a large mass such as the oceans. We don’t start off with masses of energy somehow hiding in the wings – but it continues to trickle in until temperatures rise enough to match incoming energy with outgoing.
So I don’t get the “energy hiding” issue.
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In regards to ocean heat content and the Knox paper, incidentally, that’s a current topic of discussion over at Skeptical Science; They pointed a couple things out that I had not focused on, not just the short timeframe, namely that Knox et al (a) use a very limited set of ocean data, ignoring others (sea rise, abyssal temps), and (b) the one set of data they include that has a positive trend, Von Schuckmann 2009, covers 0-2000 meters rather than the 0-700 in the others. That looks like an indication of greater vertical mixing pushing heat deeper.
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Unless and until an hypothesis about a heat driven system passes the thermodynamic and gas law smell test, the hypothesis is not worth discussing in any further detail. Especially the more difficult and, for the atmosphere-earth system, the almost insignificant details of EM Radiation and QM effects.
I suggest the purpose behind such discussions is the avoidance of the fact that the smell test was not passed from the get go. By going into the massively complex and detail discussion of such things, the failure of the smell test becomes obscured. An even worse alternative is that the AGW alarmist camp is looking for loop holes in the primary natural laws. They want to be able to eat their cake and have it too. When they can’t find those loop holes they eat their cake, your cake, and try to eat the cakes of many if not all future generations. Then they call you “bad” names when you try to get in their way to stop the generational theft.
The bottom line is they do not mean well. Their intentions are neither honorable nor honest. This includes all the random trolls who push the party line and have endless “yes, but how about…..?” questions to distract the focus from the most monumental fraud ever perpetrated on mankind. They want something for nothing and plan for everyone else to pay for it.
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Lionell Griffith @ 191 – Fraud? Deception? Personally I gain nothing from these discussions except flack from people who haven’t done the math, who cast their pre-conceptions onto what is actually pretty simple science. Although I will admit to this as a partial motivation – I try not to let that become my sole reason.
Over time I’ve come to know any number of people in the field – like all scientists, they’re people, with lots of different motivations. But like all scientists/politicians/plumbers/whatever, the vast majority do their best to do their work well. Especially when reality (the harsh critic) is right there to provide data contradicting bad work.
I certainly don’t make any money from the discussion. However, I find the idea of acting like the proverbial ostrich and hiding from reality repugnant. I really wish I didn’t see the world warming; as a prediction it’s harsh, and given the political climate we aren’t likely to deal well with it – but the objections to the data look weaker and more desperate every time I look.
Lionell, I would suggest you take a look through the information here or possibly here, or if you don’t like that source there’s the EDF and even Wikipedia – there’s lots of excellent discussions of the thermodynamics you seem to have issues with. The information is there if you look; it just won’t do you any good if your reaction to something you don’t agree with is to cry “dishonorable fraud!”
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You can lead a horse to water, but you can’t make ’em read the references…
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KR,
You have gone on and on at length, hanging yourself every step of the way.
Your understanding of physics is wanting, even to me who only had the basics in college. The laws of physics are what they are and they don’t even look at what you think they should be much less care.
You should quit before you get too bloodied up butting your head against something you can’t possibly break.
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L&C do not SIMPLY geometrically scale; their introduction of extra-tropical energy is based on detailed and cogent reasons; nor do they exaggerate with throwaway lines like: “energy exchanges 10x larger than their imbalance measures.” Please reference the basis for this.
The real simplicity here is the notion that there is an energy imbalance; Trenberth doesn’t think so with his missing heat and as for von Shuckmann, Knox and Douglass clearly show it is an outlier; in fact von Shuckmann has profound issues; this can be intially seen with the Johnson et al paper and note the concessions to limited data and mesurement techniques:
http://oceans.pmel.noaa.gov/Pdf/gcj_3f.pdf
There appear to be 2 main problems with the Schuckmann paper; firstly, how heat gets to the abysmmal depths without leaving a heating signature in the upper ocean which as NASA and various papers including by Willis and Levitus show is cooling; there may however be an answer to this question in the above paper by Johnson et al, which provides a mechanism for abyssal heating by non-ubiquitous deep convection currents.
However, the second problem is more profound; Cazaneve and Ablain have written 2 recent papers about steric sea level rise, which has a declining rate since 2003; The Cazaneve paper calculates steric sea level rise (thermal plus salinity) from 2003 to 2008 from Altimetry minus mass balance (two different ways) as 0.31mm/year, and independently calculates the value by thermal expansion from ARGO data as 0.37mm/year. This uses 0-900m ARGO data. It concludes:-
“The steric sea level estimated from the difference between altimetric (total) sea level and ocean mass displays increase over 2003–2006 and decrease since 2006. On average over the 5 year period (2003–2008), the steric contribution has been small (on the order of 0.3+/−0.15 mm/yr), confirming recent Argo results (this study and Willis et al., 2008).”
The point here is you can’t have rapid OHC increase as found by Schuckmann with a decline in steric sea level rise. And if there is no OHC increase rapid or otherwise than Knox and Douglass’s method of ascertaining the energy balance is correct.
I am non-plussed by your distinction between “energy being stored (present, just not showing), but rather energy accumulating” because there is no such distinction; if OHC is not increasing and there is no THS than AGW is not a factor.
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Roy Hogue @193,
It is interesting to note that by responding in 192 to my post at 191 in the way he did, KR identified himself as a troll intending to distract the discussion. After all, I did not name him as a troll. I simply referred to trolls as such. He need not have exposed himself the way he did. However they almost always do. They simply can’t help it.
Apparently my description of the motivation of such as he was close enough to target that he felt guilty. This is evidenced by the fact he felt it necessary to defend himself on the bases he didn’t get any money out of it.
There are more kinds of cake to eat and take than just money. His action demonstrates that he does have his hand in some kind of cookie jar that is not his to take from.
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Lionell,
Exactly right! Look at the stuff he tried to use to justify his position. I would have left him alone but for 192.
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I’ve been following this thread in addition to George’s numerous posts all over the internet on the subject for quite a while now. A few observations: The bulk of the evidence and logic he presents seems to be frequently talked around or just simply shouted down with a reference to some other work or paper that supposedly disputes or contradicts him. So far, no one has adequetely challenged his guest post that started this thread, which is quite telling in and of itself to me.
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Lionell,
If there is no radiative forcing from CO2 or other greenhouse gases then how is the surface temperature warmer than the equivalent temperature of the post albedo power from the Sun (239 W/m^2 or about 255K)??
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RW @ 198,
It’s your hypothesis not mine. I don’t have to prove anything about it except that its foundation violates the three laws of thermodynamics and the gas laws (which I and others have done repeatedly). Beyond that, I simply take the weather (aka climate) as it comes. Rant and rave about all the ya-buts you want. They are nothing but verbal noise to me. Come up with an alternate hypothesis if you wish but make sure it passes the basic smell test I referred to in 191.
You see, I don’t want to take over the economies of the earth and control the lives of everyone alive and yet to be born. I don’t resent those who are more capable, inventive, and productive than I. I don’t wish to destroy technological civilization simply because I could not create it. I am part of the collection of engineers who helped build what it is and I am still making a contribution to its building. I am proud of what I have done. I think its good, proper, and life giving. So I don’t need a fake “the sky is falling excuse” to justify my actions. I associate and trade with whom I wish and who wish to associate and trade with me. I do my thing. I live and let live. I expect nothing less nor any more in return.
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“Lionell Griffith” (199).
You are ABSOLUTELY CORRECT in your response to the troll “RW” when you say that “It’s your hypothesis not mine. I don’t have to prove anything”.
This is simply the basic scientific method.
It is what eludes these ignorant leftists.
They have tried to subvert basic science!
They are the ones who have proposed the HYPOTHESIS of man made global warming, therefore, the onus of proof is on them to prove their hypothesis with facts. This is the scientific method. It is simply how science is done. Not by consensus.
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Lionell,
I’ve not stated any hypothesis. I’m simply asking how the surface is considerably warmer than the equivalent power entering the system from the Sun? There must be something delaying the release of the incoming energy or this could not be so. I’m asking if it’s not radiative forcing from GHGs and clouds, then what is the mechanism?
BTW, I’m a stauch skeptic of AGW, and don’t believe CO2 needs to be regulated at all. I think there is likely some effect from additional CO2, but it is – if not infinitesimal, benignly small.
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RW @ 201: I’ve not stated any hypothesis.
Yes you did by implication.
RW @ 198: If there is no radiative forcing from CO2 or other greenhouse gases…
That question implies AGW’s basic premise that CO2 + other GHG’s CAUSE warming by radiative forcing ie. the returning of radiation from the surface intercepted by GHG’s back to the surface thereby using the energy twice to raise surface temperature. This is a Violation of the First Law of Thermodynamics which clearly says energy can be used only once. There by invalidating the entire hypothesis from top to bottom. After which I have no more interest in the hypothesis and the elaborate confabulations and scientific frauds used to support it.
I also have no interest in elaborating an alternate hypothesis. It is sufficient that the earth’s surface is warmer than free space without catastrophic overheating for most of the 4+ billion years of the earth’s existence. Proof? We are here aren’t we? QED! If you want an alternate hypothesis, do your own thinking on the matter and prove it yourself. Either that or pay me $35,000,000,000 to do it for you.
Further, I have no personal need nor responsibility to formulate a correct hypothesis and then prove it. It is sufficient for me to demonstrate the AGW hypothesis’s fatal weakness. The remainder of the battle against the false AGW hypothesis is political and not scientific. There is no point in ruminating over the countless and totally meaningless ya-buts that follow the fundamental fatal flaw.
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RW:
January 16th, 2011 at 1:22 pm
With Lionells permission if I may butt in here.
RW, 1343Wm2 reaches the top of the atmosphere. The figure you quote has been AVERAGED out over a surface which is a sphere and also rotates, half day half night. (i.e. divided by 4)
Therefore, at lunchtime at the equator, most of that 1343Wm2 reaches the ground on a cloudless day. (I’ve read figures of 1000Wm2)
To take an average figure and to try and extrapolate some understanding as to what happens in a given moment in time at a given specific place will lead you down the wrong path.
Here is something for you to contemplate and research if you wish.
Compare the Min. Max. Ts at a desert location which has minimal water vapour but just as much GHGs as anywhere else, to a place near the coast with higher WV and just the same CO2. That should give you an idea (and only an idea) of the relative power or lack thereof of Co2.
Hope this helps.
ps to Percival Snodgrass at #200
That comment was uncalled for and quite unfair to RW. Please desist.
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Michael,
Examining the Earth spectrum (as seen from Mars), the issue is that if the missing power was emissions from GHG’s, we should see emission lines, rather than absorption lines. It’s biased up by what looks like the Planck spectrum of the average temperature of the atmosphere, which is what I would expect and the bias around the absorption lines is due to radiation from clouds since there is very little water vapor and not a lot of atmosphere between the cloud tops and space. But what this seems to say, is that the atmosphere is emitting a broad band Planck spectrum and not narrow band emission lines. Trenberth claims about twice as much power is radiated by the atmosphere, than passes through the transparent window from the surface and/or cloud tops into space. Surely, if this were the case, we should be seeing large, well defined emission lines.
Displaying with a wavenumber scale can be misleading. Here’s a little C program here which calculates the power spectrum for the frequency and wavelength density forms of Plank radiation at an arbitrary temperature. It also calculates the mean wavelength/frequency/wavenumber where half the power is at higher frequencies and half at lower frequencies. The peak in the plot you showed (using the frequency form of a Planck spectrum) is about 17u, the peak of the wavelength density form is about 10u, but in both cases, the peak power density occurs around 12.9u for typical earth temperatures. Also, when displaying wavenumbers, frequency or wavelength, it’s more appropriate to use a log scale, rather than a linear scale.
http://www.palisad.com/co2/code/test.c
http://www.palisad.com/co3/code/k.h
Compile as “gcc -O test.c -lm -o test”. Run as “test TEMP”, where TEMP is the desired temperature.
A wavenumber (or frequency) display is somewhat misleading because if gives the false impression that most of the power is at wavelengths greater than the 15u Co2 line and subject to CO2 and H2O absorption, when in fact, most of the power is at wavelengths less than 15u and in the middle of the transparent window between 9u and 14u (with the ozone gap at 10u).
The e=a relation would hold true for a single gas. The more general case is that the energy in is equal to the energy out. Most of the energy absorbed by GHG’s is transferred to the N2 and O2 as kinetic energy making them move faster (i.e warm up). If the GHG’s didn’t heat up the atmosphere, we would have CO2 and H2O at 100’s of degrees C and O2 and N2 at absolute zero. The kinetic theory of gases dictates that an equilibrium will be reached where both are at the same temperature.
If equal amounts of N2 at 100C and O2 at 0C are mixed together, the N2 and O2 will become the same temperature. The same happens with hot GHG’s that have absorbed photons and cold ground state N2 and O2 in the atmosphere. So, once the N2 and O2 have absorbed this power, how does it get out of the atmosphere, if not by radiation?
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George, you say this:
“If the GHG’s didn’t heat up the atmosphere, we would have CO2 and H2O at 100′s of degrees C and O2 and N2 at absolute zero.”
Doesn’t conductive heating of N2 and O2 occur via the surface.
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And the spin continues.
http://www.nytimes.com/2011/01/16/weekinreview/16wald.html?src=twrhp
Now the Obama administration says the recession is good because it’s stemming global warming.
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George, next they will be saying that they can “see it in the temperature trends”. Really, they have every possibility covered in some way as more “evidence”.
What they don’t realize is that the average American sees right through this kind of babble. That is why the change in Congress and why that will continue to happen.
By the way, excellent post thread here! I have been on the sidelines watching (reading) all the while learning and better yet enjoying the way you have unsettled the “settled” science. Keep up the good effort!
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I’m a long time AGW Sceptic and have lost count of the number of threads and comments, on numerous sites that I’ve read but this post stands head and shoulders above the vast majority.
I’ve learned much today about the Physics of the Greenhouse effect, thanks to George, Mike Hammer and Bob. Thanks guys but especially to Bob who demonstrated enormous courage and resilience to keep fighting his corner. I salute him for having the spheroids (npi) to participate and debate in a clearly hostile camp.
If more of his kind had his cojones then I may never have made the leap from believer to sceptic that I did!
I was less impressed with the negative thumbings that this thread threw up. The phrase “shoot the messenger” sprang to mind and brought back memories of my early visits to RC where I discovered a level of unpleasantness that made me suspect that there was more to AGW than the “experts” would have us believe.
I’ll doubtlessly get flamed for this but, WTH, I’ve started so I’ll finish.
Don’t make the same mistake as the warmists did. Be respectful.
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RoyFOMR, you won’t get flamed (for this comment anyway)
Bob (spherical) Does not have cojones, instead he has religion. (debate on the relative worth of either we’ll save for later). He was here many months before this and he picked up his ball and went home.
I do agree that the mostly respectful discussion has been worthwhile.
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Michael,
The Earth spectrum seen from Mars does seem to have a lot more power in the absorption bands than I expect. Although, it really doesn’t matter to my hypothesis which bands the power is emitted from, the bottom line is that half of whatever radiated power is absorbed by the GHG’s in the atmosphere goes up and out into space and the other half of returned to the surface. I will admit that if this power is emitted only in the same absorption bands, then the radiative balance I’ve described in the article is easier to explain. However, I still have a problem with large blobs of O2 or N2, at some temperature T, in the vacuum of deep space. It would seem to never cool and regardless of it’s temperature would be completely invisible except for it’s gravity. Sounds more like dark matter to me …
But I must say, the half amplitude in the absorption bands does agree with my theory that the most opaque an atmosphere can be to power radiated from the thermal mass is 50%. Even if it absorbed 100%, 50% is re-rediated out into space, although I didn’t expect this to be true for all frequencies. Do you know of any high resolution views of the Earth’s spectrum, as seen from space? Most of the high resolution IR spectrographic instruments seem to point away from the Earth. You would think someone would have pointed one back, if for no other reason, then for calibration purposes.
Do we see the same half amplitude effect in images of space objects from Earth? For example, if this was seen on Venus, it would erode another large hole in CAGW centric theories. Nothing shows up after a quick search.
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Roy Hogue @ 193, 196 – You’ve just proven the point I made in the first paragraph of #192. ‘Nuf said.
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cohenite – I’ve read L&C 2001, 2009, and 2010. They say a fair bit, then dismiss energy exchanges and use a geometric (adjusted for insolation) extension of their tropical data for the globe – Murphy and Chung both show that if you use global data you get very different answers. Trenberth 2010 (yes, yes, I know, Trenberth is categorized by many with Hansen and the Antichrist) shows much the same, and discusses the magnitude of ENSO, precipitation, and other factors as 10x the TOA imbalances discussed by L&C. Your mileage may vary, but I find L&C unacceptable as a result. But I’ll agree to disagree…
As to Knox and Douglas – I’ve looked at both the raw and adjusted Argo data, and I would want ~25 years worth to establish a statistically significant trend based on the variance shown in the data so far. I will clearly state that the Argo alone data shows a slight decrease, but that it’s not statistically convincing. Yet. Too much noise so far. I hope it continues to decline.
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George White / co2isnotevil – Your modeling runs show a 3.6 W/m^2 difference at TOA, as opposed to the more commonly mentioned 3.7 W/m^2 difference (<3% difference). What do you calculate as the no-feedback temperature increase based on that TOA imbalance?
I keep getting the impression that your argument is based on semantic interpretations and objections thereof of the "back-radiation" values, as your modeling comes out with essentially the same results as everyone else’s. Do you distrust your modeling?
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co2isnotevil @ 210 – GISS has some data here on TOA spectra – I don’t know if that’s sufficient for your purposes.
O2 and N2 won’t cool efficiently (as globes of gas in space) – of course, they won’t heat efficiently, either.
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KR,
Of the 3.6 W/m^2 of incremental absorption, 1.8 arrives at the surface, is multiplied by the surface gain of 1.6, producing a net increase of 2.9 W/m^2, which starting from 287K will increase the temperature by 0.6C.
This is not the ‘pre feedback’ value, but the post feedback value averaged over a year. Since the average yearly surface gain, g, is related to the average yearly size of the transparent window, T, by the relation, g = 1/(T + (1-T)/2), a reduction in T will also increase g. The slight decrease in T will increase g from about 1.61 to 1.62, but the total surface temperature increase is still approriately rounded to 0.6C. Pre feedback. 1.8 W/m^2 will increase the surface temperature by only about 0.33C.
The only feedback that this does not explicitly include are changes in reflectivity owing to the varying reflectivity from more/less snow and ice when averaged over a year. However, as it warms, there’s more winter snow owing to more evaporation and precipitation, which reflects more power when averaged over a year and besides, we are relatively close to minimum ice anyway. Greenland and Antarctica will not melt as long as 1) it remains dark for half of the year and 2) the base altitude remains 1000’s of meters above sea level (think lapse rate). Most of the dynamic range of this feedback effect kicked in as we exited the last ice age and there’s not much more to be had. We will need to wait for plate tectonics to move Greenland and/or Antarctica towards the equator first.
My argument is based on the fact that if you consider only radiation in the radiative balance, it all works out as the physics demands and that non radiative effects are moot. My point is that things like thermals and latent must have a net zero effect on the energy balance, therefore must be returned as ‘back radiation’ in order for the math to work. This gives the false impression that all of this extra returned power is GHG related, when it clearly is not. I object to analysis that adds superfluous factors to add degrees of freedom in order to explain things that aren’t happening, for example, catastrophic warming from man’s CO2 emissions.
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KR, re212
No, this data is not useful. It only shows total LW or SW power and not the spectral decomposition. Besides, the weather satellite data has no spectral information, other than is the received radiation LW, SW or NIR.
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co2isnotevil @ 213 – “This is not the ‘pre feedback’ value, but the post feedback value averaged over a year. “ What about water vapor feedback? Ocean absorption changes of CO2 driven by temperature? Vegetation albedo changes? Ice melt? Cloud changes (which could include both positive and negative feedback, depending on cloud height)?
I don’t see how this can possibly include the feedbacks. It’s also the lowest climate sensitivity value I’ve seen, including both Schwartz and Lindzen/Choi – very much an outlier.
As to thermals and latent heat – they move energy to the troposphere/stratosphere, where it gets radiated in both directions. Given that those layers of atmosphere are above ground level GHG’s, that will change things somewhat…
As to “catastrophic” – personally, I can’t consider myself in the group of people who consider global warming catastrophic. Annoying, yes, expensive (social adjustments, $$$), but I don’t see the end of the human race as a result.
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co2isnotevil @ 213 – Greenland is getting strong accumulations of snow due to higher WV values (about 4% according to what I’ve seen) over the last 50 years. But the ice melt at the periphery is still pretty high, and it’s still losing ice (Rignot 2007, Wouters 2008, Velicogna 2009). I don’t know if the final albedo conditions for current conditions have been reached yet.
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This does include water vapor feedback, unless you think it operates over time scales greater than a year. It actually includes all feedbacks that operate on time scales of decades or less, since the 1.6 gain value is a 25 year global average, which varies by less than 4% peak to peak over the 25 years of data and if anything, has shown a small downward trend.
BTW, the whole purpose of this article is to point out that the 3.7 W/m^2 often cited is really twice as big as it should be, in which case all estimates based on this value should be adjusted in half.
That thermals and latent heat move heat around is irrelevant. All this is doing is moving energy around the Earth’s thermal mass in order that the planet be capable of maintaining it’s energy balance. The numerical dependencies on the planets energy balance itself are completely independent of these factors. It’s a cause and effect thing. Are thermals and latent heat a cause or a consequence of the planets relentless drive towards radiative equilibrium with the Sun?
The effect is so not catastrophic, that it’s not worth obsessing about and certainly not worth devoting any resources to mitigate when for all intents and purposes, adding CO2 to the atmosphere results in far more good to agriculture than harm to the climate. It’s really too bad it’s not as powerful as some might claim. Otherwise, we might be able to mitigate the next, inevitable ice age.
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KR,
If all 3.6 W/m^2 affected the surface as 3.6 W/m^2 of incremental solar power would, the pre feedback effect would be 0.6C and the post feedback would be about 1C and more in line with other skeptics claims.
From Stefan-Boltzmann, here’s a useful table to grasp the magnitudes of power involved:
287.0K -> 384.746 W/m^2
287.3K -> 386.357 W/m^2 (delta 1.61 W/m^2)
287.4K -> 386.896 W/m^2 (delta 2.15 W/m^2)
287.6K -> 387.974 W/m^2 (delta 3.23 W/m^2)
287.7K -> 388.513 W/m^2 (delta 3.77 W/m^2)
288.0K -> 390.137 W/m^2 (delta 5.39 W/m^2)
288.5K -> 392.850 W/m^2 (delta 8.11 W/m^2) – IPCC best case
290.0K -> 401.087 W/m^2 (delta 16.34 W/m^2) – mythical 3C rise
292.0K -> 412.266 W/m^2 (delta 27.52 W/m^2) – IPCC worst case
Even if there eas 3.7 W/m^2 of input, how can you expect 16.24 W/m^2 of affect, let alone 27.52 W/m^2. This kind of power multiplication is out of the realm of possibility and pure fantasy considering that only half of the absorbed power actually affects the radiative balance at the surface.
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co2isnotevil @ 217 – I still (and have never) seen how the 3.6/3.7 W/m^2 imbalance at the top of the atmosphere is halved (3.6 being your value, within 3% of everyone else’s).
There is a difference of 3.6/3.7 W/m^2 between incoming and outgoing radiation for a doubling of CO2 based upon your models and everyone else’s – so there is agreement there.
Some of that is additional absorption at ground level. Some of that is due to the CO2 effective emission altitude changing upwards as CO2 concentrations increase. But the effect is 3.6/3.7 W/m^2 difference between incoming and outgoing.
Again – do you not trust the model runs you have done???
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A temperature increase of 1.1C, from everyone else’s calculations, at ground level results in an effective increase of ground IR of 5.9 W/m^2 (using your older number of 385 – with the more recent number from Trenberth 2009 it’s 6.1 W/m^2).
Given that surface temperatures affect IR, and that the atmospheric windows/IR re-emissions are not equal to the TOA emissions (which you have calculated to roughly equal values derived elsewhere), how are you justifying your numbers?
—
I believe you are getting hung up on the semantic interpretation of the “absorbed” number, without looking at the actual differences in TOA radiation values. That’s the forcing.
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KR, how could Greenland “still be losing ice”
You do know that this is 2011?
Even Wiki seems to have stopped the clock at around 2007 http://en.wikipedia.org/wiki/Greenland_ice_sheet
When will you say something about arctic ice and antarctic ice to demonstrate that you have a neutral “scientific” view of ice GLOBALLY?
I know it is hard to imagine a world of ACTUAL MEASUREMENT instead of some paper but hey take a look around!
P.S.
Why was Lindzen and Choi abbreviated in your post @ 211 as LC but all of your supporting references were spelled out? Some people might think this was on purpose…….
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KR @ 212
I suppose you are making a case for O2 and N2 being the cause for warming (as in globes of gas in space) since they make up the majority of atmospheric composition?
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KR; Murphy and Chung are not responding to L&C 2010, but L&C 2009; Murphy says: “I also show that a simple, point-by-point regression of outgoing radiation against surface temperature gives better slope estimates than the interval method used by Lindzen and Choi (2009).” L&C do not use a slope interval method in their 2009 paper but have calculated TOA imbalnces in the tropics and then calculated imbalances i the remainder using insolation measurments. The tropics is where the bulk of Eath’s insolation is; energy moves north and south from the tropics; L&C measure that so their methodology is good. They find no +ve TOA imbalance. I don’t know what imbalance Murphy finds and whether he has done modelling rather than actual measurments; do you? But with L&C you are not thinking laterally; if L&C were wrong there would be a THS; there is not.
You are also still mssing the point with Knox and the ‘shortness’ of the data; that data, all 7 years ot it, is the best we have and it shows declining OHC; that means no storage/accumulation of energy and therefore no equilibrium climate sensitivity; Knox, again based on actual measurments, also supports L&C in finding no +ve TOA imbalance.
This probably exp[lains why Trenberth is desperately trying to get rid of the null hypothesis with climate science; that would mean climate science would be the equivalent of received knowledge; you know, like the ten commandments. Really, Treneberth is not fit to clean the toilets.
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George,
How are they getting a 1.2 C intrinsic increase for 2xCO2? I assumed gain was included in this number, but maybe it isn’t?
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KR,
You claim that a 1.1C rise results from 5.6 W/m^2 of incremental power, which is close enough to the real value of 5.933 W/m^2, that I will agree. So, how can 3.7 W/m^2 cause 5.6 W/m^2 of warming? By gain! Note that the gain to boost 3.7 W/m^2 into 5.6 W/m^2 is about 1.5. Trenberth’s 6.1 W/m^2 requires a gain of about 1.65, which is a little larger than my value of 1.61, although mine is a 25 year global average which includes most feedback effects. However, none of these comes close to the required gain of 4.4 to cause a 3C rise, even though they all include most feedback!
What the IPCC calls incremental forcing at the top of the troposphere is calculated as the incremental power that would be absorbed by the atmosphere by doubling CO2 concentrations. That is, the direct effect of decreasing atmospheric transmittance, T. It does not account for the 1/2 of this power that must be radiated out into space in order to achieve radiative balance. As a result, only half is left to return to the surface in order to boost it’s temperature and only this half is subject to the surface gain of 1.61.
Which values do you think I need to justify? The only number I should is the 0,241 average atmospheric transmittance. Everything else follows from this value. Trenberth assumes 0.18, which he never justifies in his paper, but a smaller window doesn’t help your case anyway, as more than half of what is absorbed would need to be emitted in order to achieve radiative balance making what’s left to heat the surface even smaller. My values comes from HITRAN driven, line by line 3-d atmospheric simulations using measured gas concentrations, including water vapor.
Suppose T=0.234 making the window 3 W/m^2 smaller (the IPCC definition of ‘forcing’ at the top of the troposphere). Given the 50/50 split, 1.5 will be emitted into space and 1.5 back to the surface. This 1.5 is amplified by the post feedback gain of 1.6 increasing the surface power by 2.4 W/m^2. up to 387.4 W/m^2. resulting in 90.7 W/m^2 passing through the window and 296.7 W/m^2 absorbed by the atmosphere, where 148.4 W/m^2 goes up and down. At the top is 90.7 + 148.4 = 239.1 W/m^2, where 239 W/m^2 is expected. At the bottom, 239 + 148.4 = 387.4 W/m^2, which is also expected.
The deficit at TOA is 3 W/m^2 and the surface power increased by 2.4 W/m^2, which is equal to 0.5 * 3.0 * 1.6 = 2.4 W/m^2.
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Re:
Both the gyprock (Plaster board) wall and the mirror are vertical. The down light is about half a meter away from the wall. The mirror is closer to the wall. The shadow of the mirror is cast well below the bright spot(they do overlap a little). Just repeated the experiment using a plain white paper instead of a mirror. Works well also!
Using a yellow paper with a sheet of cardboard behind it, the bright spot became tinted yellow.
You need to do this and see it!
Then have a look at the theory of a Yagi antenna.
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Simple is not bad. Simple is good!
If radiation that travels horizontal is reabsorbed it did so after gaining altitude. From this higher altitude it may be re radiated again. Now in the up direction it has less atmosphere to travel out of. In the horizontal direction it will gain more altitude. In the down direction it has more chance of being absorbed again before getting to the surface.
Another “simple” way to describe this:
If CO2 forms a warm layer around the earth then that has increased the radiating surface area of the planet at the CO2 wavelengths. It has not however increased the absorbing surface area at the other wavelengths.
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Wow, some of you folks would make AWFUL engineers. Some key rules to remember about Power, Energy, and Temperature;
Units of Power (W/m^2, specifically Power per unit Surface Area) are NOT interchangeable with units of Energy (Joules, Calories, BTU’s, etc. etc.) anymore than units of BACON are interchangeable with units of PIG, Yes indeed they are related but they are hardly interchangeable.
Temperature is the result of the total energy absorbed by ANY material AND it’s thermal capacity. You cannot just state a power level and extrapolate a resulting temperature. A thousand watts/m^2 impinging on an insulator will not raise it’s average temperature as much as 10 watts/m^2 impinging on a good thermal conductor. For a good empirical example try leaving a slab of plastic insulation and a steel pipe wrench out in the blazing sun in July (Northern Hemisphere). Both are receiving the identical amount of “radiative forcing”, yet when you pick them up one is quite a bit more uncomfortable to hold than the other. Why is that? It’s the Speed of Heat (yes indeed such a measure exists; refer to the “Thermal Diffusivity” of a material). Unless the radiative properties of the alleged “Greenhouse Gases” can materially change the speed of heat through the atmosphere of the Earth the AGW theory is flawed.
The climate of the Earth is a CYCLICAL System, the energy input changes from almost NOTHING (star and moon light) to a BLAZING input from the SUN. The REAL issue is the SPEED of HEAT flow through the system. UNLESS THE BACKRADIATION FROM “GHG’S” CAN SLOW THE FLOW OF HEAT IN A SIGNIFICANT MANNER RELATIVE TO THE 24 HOUR CYCLE TIME THE “GREENHOUSE EFFECT” CANNOT CHANGE THE “EQUILIBRIUM” TEMPERATURE of the Earth. In fact the exact opposite happens, as GHG’s replace NON-GHG’s more energy flows through the atmosphere of the Earth at the speed of light (rather speedy) versus the speed of heat (comparatively sluggish) . This causes the temperature of the gases in the atmosphere to reach a final daylight temperature slightly faster after sunrise, and to cool down slightly faster after sunset. These gases CANNOT cause any new higher (or lower) EQUILIBRIUM temperature to occur.
If you are at all interested in the response time of complex systems you should check out the field of electrical engineering, there is quite a fit of knowledge about the response time of complex systems. This knowledge includes studies in both the “time domain” and the “frequency domain”. All of this has been well understood for many decades. Perhaps the climate ”scientists” would have benefited by reading one or more textbooks from other fields.
Cheers, Kevin
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Kevin,
“Unless the radiative properties of the alleged “Greenhouse Gases” can materially change the speed of heat through the atmosphere of the Earth the AGW theory is flawed.”
This is what additional GHGs do – further delay the release of incoming energy from the Sun from escaping, causing the surface to warm (at least in theory, assuming nothing else were to change).
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Please allowme to rephrase my orignal statement;
Original:
“Unless the radiative properties of the alleged “Greenhouse Gases” can materially change the speed of heat through the atmosphere of the Earth the AGW theory is flawed.”
Corrected:
“Unless the radiative properties of the alleged “Greenhouse Gases” can materially change the speed of heat through the atmosphere of the Earth WITH RESPECT TO THE CYLICAL NATURE OF THE ENERGY INPUT (i.e. 24 hours) the AGW theory is flawed.”
Also, please note the the replacement of “non-GHG’s” by “GHG’s” actually cause more energy to flow through the atmosphere of the Earth at a FASTER rate, not the SLOWER rate that has been assumed.
Cheers,Kevin
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Let me provide an empirical example as well;
Let’s postulate that your commute to work each day takes 30 minutes round trip. If a persistent 5 minute traffic delay (a four lane road becomes permanently a two lane road, or a “GHG” slows the flow of energy) occurs does your day magically become 5 minutes longer?
So if the “GHG’s” slow the flow of heat by a second (a wild conjecture, a more realistic number is probably a few milliseconds) does the temperature slowly rise? Or does the time delay from sunrise until the peak surface temperature for that day just happen one second later? Also please note that this delay in the peak temperature does not cause a slow rise in temps, the later peak temperature only causes a larger temperature differential after sunset, so the gases in the atmosphere cool more quickly after sunset.
The AGW hypothesis is FATALLY FLAWED, the fact that the name has been changed multiple times in a few short years is a good empirical clue. Ohm’s law has the same name after many many decades.
For those skilled in the theory of electrical engineering, the “backradiation” from “GHG’s” is analogous to a time delay added to an AC signal. In many years of practicing the art of electrical engineering I have not yet learned how to turn a time delay into a DC offset. But maybe my skills are limiting my results.
Cheers, Kevin.
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Kevin,
What changing CO2 levels do is modify the surface gain. The surface gain is defined as the ratio of emitted surface power to solar power incident to the surface and is given by, 1/(1-A/2), where A is the probability that a photon emitted by the surface will be captured by a GHG molecule, which is a function of concentration (I can derive this if necessary). We know by various means, that the size of the transparent window in the atmosphere, relative to the emitted energy spectrum of the surface, is about 24% (Trenberth claims only 18%). This means that nearly 76% of the power emitted by the surface will be absorbed by the various GHG’s in the atmosphere, including the water in clouds. This high absorbency is why many warmists believe that GHG’s are such a big deal, of course, the 2/3 of the planet covered by clouds contributes quite a bit to the total and this component is mostly independent of CO2 levels. But, if we plug 76% into the gain equation, we get 1/(1-.76/2) = 1.61. This is the multiplier, applied to incident forcing, solar or otherwise, amplifying it into the required steady state surface power. For example, the post albedo incident power is about 240 W/m^2 and 1.61 times this is 386 W/m^2, corresponding to the average surface temperature of about 287K. And of course, as you should already know, gain quantified like this is a post feedback attribute of the system.
The gain of 1.61 is a long term average and is confirmed by 25+ years of satellite observations. It includes the net effects of any feedbacks that operate on time scales less than a decade, which describes most of them, including all water vapor related feedbacks. Only the long term effect of the ebb and flow of global ice is not accounted for, but the dynamic effect of this is, as the average between summer and winter, where snow covers what was ice during an ice age.
Most of the positive feedback from ice that contributes to warming was given up as we left the last ice age and because we are close to minimum possible ice (considering that winter still occurs), there’s not much impact left from this. However, the positive feedback from growing ice which reinforces cooling can be quite strong going forward. Few people understand the asymmetric nature of ice related albedo feedback, but the limits of this delineate the difference between glacial periods and interglacial periods.
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Kevin,
“So if the “GHG’s” slow the flow of heat by a second (a wild conjecture, a more realistic number is probably a few milliseconds) does the temperature slowly rise? Or does the time delay from sunrise until the peak surface temperature for that day just happen one second later? Also please note that this delay in the peak temperature does not cause a slow rise in temps, the later peak temperature only causes a larger temperature differential after sunset, so the gases in the atmosphere cool more quickly after sunset.”
All of the heat accumulated during the day is not lost at night, though curiously CO2 seems to be the least effective GHG at preventing heat from escaping into space during the night time hours.
10
RW @ 233 – I’ve always hated the “slows the energy down” explanation of the greenhouse effect; it’s really not accurate.
A much cleaner and more accurate explanation can be found by looking at the greenhouse gases effect on the thermal radiation from the Earth.
We get a certain amount of energy from the sun as visible light, which is pretty much unaffected by greenhouse gases. In order to stay at (or around) the same temperature, the Earth has to radiate that energy away again. Given the temperature of the Earth, that goes out as infrared, thermal radiation. To stay at the same temperature, what goes out must equal what comes in.
Now, the amount of thermal radiation can be described with:
Power = Emissivity * sigma * Area * Temperature^4
where sigma is the Stefan-Boltzmann constant (5.670 400(40)×10^−8 W·m^−2·K^−4), temperature is in degrees Kelvin, and emissivity is the relative ability of an object to emit radiation compared to a theoretic “black-body” which is perfectly emissive (a black-body would have an emissivity of 1.0).
Note that if emissivity changes, but the temperature remains fixed, the power radiated by an object (or the Earth) changes.
Most of the ground and the water have an IR emissivity of 0.94-0.99, clouds have fairly low emissivity, and greenhouse gases keep the earth warmer than it would be otherwise. The Earth and atmosphere together have an emissivity of ~0.64 to space (measured) in IR.
So what happens with additional greenhouse gases? They absorb IR, re-emit it half up and half down, making it harder for the Earth’s surface to send IR to space. Emissivity of the planet goes down when greenhouse gases increase. That means there’s a difference between the energy coming in from the sun and the energy going out to space. Things warm up, the temperature increases, power radiated goes back up to equal the incoming sunlight again.
—
Those are the basics – any added greenhouse gas will change emissivity to space by a little bit. The big points of discussion at this time are mostly in terms of feedbacks that _might_ amplify or damp this temperature effect. Will clouds increase with temperature? Will those be high clouds (amplifies by keeping heat in) or low clouds (damps by reflecting sunlight)? How about water vapor? Water vapor is a much stronger greenhouse gas than CO2, although it tends to respond very quickly (evaporating or raining as temperatures change, so it’s more of a feedback).
This is the “climate sensitivity” to a greenhouse gas change. George White (in this article) argues for a sensitivity of ~0.5C to a doubling of CO2, Lindzen and Choi argued about 1.0, most of the work I’ve seen argues for somewhere between 2-4.5C.
—
I hope that isn’t too wordy; I do get a tendency to ramble on…
10
KR,
The calculated and measured emissivity of the Earth is closer to 0.8. The average temperature of the emitting portions of the planet (34% surface @288K 66% clouds @262K) is about 271.7K, corresponding to 309 W/m^2. The emitted temperature of the planet is 255K, corresponding to 240 W/m^2. The emissivity is calculated as 240/309 = 0.77. Also, the tallest cloud tops have an emissivity approaching 1, while the average emissivity of clouds is closer to 0.8 (according to the ISCCP data). Otherwise, we wouldn’t have those nice cloud top temperature maps we see on the weather channel. The other way to consider this is that the average surface power leaking through the clouds is proportional to (1-e), where e is the emissivity of the clouds. Even on average, not that much leaks through.
It’s important to keep the delay part in mind, since the photons emitted as radiation up and down are not the same photons that were initially absorbed. The fact that the IPCC forgot this is why they forgot to subtract the power emitted up from the incrementally absorbed power.
The article implies that the ratio of the required surface power to the incident solar power is equal to Ps/Pi = (1-a)/(1-A/2), where a is the albedo and A is the fraction of the surface power absorbed by the atmosphere (1 – T). Using the measured emissivity of 0.77 (which is the same as A), Ps/Pi can be calculated as, (1-.3)/(1-.77/2) = 1.14, such that, Ps = 1.14*Pi = 1.14*341.5 = 389 W/m^2, corresponding to a 287.7K surface temperature, which yet again is more measured data that validates my results. How many more ways does this have to work before you start to believe it. Have you tried to make any of these calculations work assuming anything other than half of absorption goes up and half returned to the surface? It isn’t going to happen as the 2 in A/2 (above) was an emergent constant, not an assumption.
Relative to feedback, the only properties that can affect the steady state surface temperature are the average albedo and the average absorption, per the above formula. The small change to A caused by doubling CO2 is made smaller by the factor of 2 (the point of the article). Any albedo trends over the last 25 years of accurate measurements are non existent, so it’s clear that the only thing changing is T, whose effect from doubling CO2 is 3.7 W/m^2 less transmission, decreasing the transmission from .241 to .232 and increasing A from 0.76 to 0.77, increasing the gain from 1.129 to 1.138, increasing the equilibrium surface energy by less 0.5%, or by less than 0.7C. The incremental absorption from of all anthro CO2 to date is less than 2 W/m^2, yielding an effect of about 0.4C, which is why ‘detectable’ trends only appears in fudged data sets, since this is too small to discern, relative to the natural variability.
20
Can i ask a stupid question to all? The answers will help me understand more about what you guys are saying. Is that OK?
If we start at the basics i will describe ny understanding of how things work and we can go from there. ThEarth is hit by various things from the sun and these are:
1, Sunlight or visable light, this passes straight through the atmosphere strikes the Earth and is absorbed as heat. The moisture in the surface then heats up and evaporates (WV) and so the surface cools the WV then rises up (hydrologic cycle).
Correct (Yes or no)
2, Ultra Violet light strikes the atmosphere and some/most is absorbed by O3 the rest strikes the Earth and then what happens to it?
3, Short wave infra red radiation (Far IR) passes straight through the atmosphere as if it was not there and strikes the Earth and is reflected back but due to the doppler effect (rotating planet) there is a frequency shift long wave IR (Near IR) and this interacts with GHG’s.
Is this correct?
Any comments or corrections would be appreciated
TIA
Crakar
10
I haven’t really established that the global emissivity and A are the same thing, but they are related by the more easily derived expression,
e = (1-A/2)/(1-p+p*Pc/Ps)
where A is the fraction of surface power absorption, p is the percentage of cloud coverage and Pc/Pd id the ratio of cloud power to surface power and can be easily measured from the ISCCP cloud data. A scatter plot showing this ratio is between 0.66 and 0.80 is here (I will use a value of 0.7),
http://www,palisad.com/co2/div2/se_ce.png
From ISCCP, the cloud fraction is 66.4% and from above A is (1-T) = 0.759.
e = (1-.759/2)/(1-.664 + .664*0.7) = 0.77, just as was measured.
This works because Ps/Pi = (1-a)/(1-A/2) and e/Pi = (1-a)/(p*Pc + (1-p)*Ps). If neither was true, this would not get the right answer.
George
10
craker24, re236
1) Yes, except for one caveat. Latent heat comes from the thermal mass in the oceans, but is carried with the water as potential energy. This returns to the water as the vapor, which condenses to fall as rain, eventually to return to the ocean.
2) UV light hitting the surface is absorbed just like sunlight
3) No. The relative motion between the atmosphere and surface is too slow and what little doppler shift there is would only affect observed IR away from the planet. Also, SW IR is also subject to many absorption bands.
10
George,
“The incremental absorption from of all anthro CO2 to date is less than 2 W/m^2”
Isn’t it more like 2.7 W/m^2 since the effect of CO2 is logarithmic? That is going from 280 ppm to 390 ppm equals about 75% of the forcing of 2xCO2?
10
Or maybe it’s more like 70%?
10
CO2isnotevil @ 238
Thanks for that, it looks like my thoughts on 1 and 2 were about right but 3 i am still not sure of.
If i re phrase the question i would ask, Where does the IR that gives us the greenhouse effect come from?
10
crakar24,
“Where does the IR that gives us the greenhouse effect come from?”
The Sun. The incoming short wave infrared energy from the Sun is mostly transparent to the clear sky atmosphere. Cloudy sky is obviously different, as a lot of the energy is reflected off of and absorbed by the clouds – a much smaller amount makes it through. The short wave energy that hits the surface is radiated back up in the form of long wave infrared, which in certain wavelengths is absorbed and re-radiated by greenhouse gases and/or clouds. In effect, presence of greenhouse gases and clouds in the atmosphere delay the release of infrared heat energy by redirecting some of it back toward the surface, which makes the surface warmer than it would be otherwise.
This is my basic understanding of at least.
10
RW,
That is my understanding as well.
My question however is why (refer to point 3 in my post 236)
The only way the IR energy can reflect/bounce off an object and shift in frequency is via the doppler effect. However CO2isnotevil stated in 238 this is not entirely correct.
So therefore if SW from the sun passes straight through the GHG’s as if they were not there and there is little doppler shift at the surface then in theory they should leave the same way they came in and the green house gas effect is virtually non existent…yes?
10
crakar24,
Except that the atmosphere randomizes the direction of the outbound radiation that was previously absorbed. Because of this, half is sent down to the surface and only half escapes the planet. The greenhouse effect is the half that’s returned to the surface.
10
crakar24,
“The only way the IR energy can reflect/bounce off an object and shift in frequency is via the doppler effect. However CO2isnotevil stated in 238 this is not entirely correct.”
I think the main reason why the earth radiates in the LW is because its temperature is much cooler than the Sun. Because of Planck’s law of black body radiation.
10
Sorry i still dont get it (i know i am frustrating but only due to lack of knowledge).
IR comes from the sun.
Assuming a clear sky how much of this incoming IR interacts with GHG’s?
The IR strikes the surface and gets reflected back into space how much of this interacts with GHG’s.
My question is what is the difference in incoming IR and out going IR?
10
247 was in response to CO2isnotevil, then i saw RW’s post. So ir can change frequency due to temp differences?
10
crakar24,
“My question is what is the difference in incoming IR and out going IR?”
At the surface the difference is a little over 60%. That is each 1 W/m^2 of power from the Sun is amplified to about 1.6 W/m^2 at the surface due to the greenhouse effect.
10
crakar24,
“So ir can change frequency due to temp differences?”
Yes, I think so. The surface of the Sun is much, much hotter than the surface of the earth; therefore, according to Planck’s law, it radiates in much higher wavelengths. This is the SW energy from the Sun that travels through space and passes through atmosphere of the Earth, and when re-radiated by the cooler surface of the earth, is in the form of LW infrared dictated by Planck’s law.
10
“The surface of the Sun is much, much hotter than the surface of the earth; therefore, according to Planck’s law, it radiates in much higher wavelengths.”
I wrote this in 249, but it should say:
“The surface of the Sun is much, much hotter than the surface of the earth; therefore, according to Planck’s law, it radiates in much shorter wavelengths.”
10
I thought IR came in at short wave (High frequency IR) and left as OLR outgoing long wave radiation which would seem to indicate you got it right the first time, but i could be wrong.
10
crakar24
Every object radiates some energy based on it’s temperature and emissivity. [Emissivity = 1.0 is never seen in reality, but that’s the “black-body” emissivity.]
Due to the Sun’s temperature, only a tiny fraction of the light coming in is IR and interacts with any greenhouse gases. Most is visible light (0.4 to 0.7 micrometer, the peak of the curve) and UV, much shorter wavelengths. The basic emission curves for black-bodies at Sun and Earth temperatures is shown in the linked graph:
Black body spectra of Sun/Earth
The Earth absorbs sunlight (warms the ground and ocean), then radiates IR based on it’s temperature (different curve). Some of that outgoing radiation gets absorbed by GHG’s, the GHG’s radiate in all directions based on their temperatures, and some of that energy goes back to the ground – less reaches outer space.
10
Sorry, but I still believe that it all comes down to the “speed of heat” through the atmospheric system of the climate of the Earth
Yes this may seem a silly notion, but all energy (electromagnetic and otherwise) has a propagation speed, LIGHT, SOUND, MECHANICAL VIBRATIONS and HEAT. Every source of energy has a speed that it propagates at. This speed is determined by the materials that the energy source is flowing through. The materials determine the outcome, the energy source has very little say in the final result.
Yes indeed “gain” may cause a system to achieve a new “higher equilibrium state” (i.e. a higher temperature), but only if the “gain” is a constant factor that can override the frequency content of the system. I.E. unless the “extra” energy from the ”GHG’s” can SIGNIFICANTLY slow the natural flow of heat outwards from the Earth to the cold vacuum of space the AGW hypothesis is FATALLY FLAWED.
Cheers, Kevin
10
167Sphaerica (Bob):
January 15th, 2011 at 1:32 am
“Convection is the simple transfer of heat when two bodies are in contact (i.e. you put your hand on a hot plate).”
However, this would be conduction, not convection. Convection is “the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.”
10
George,
A question:
The Trenberth 2009 paper and few other sources seem to be claiming their ‘back radiation’ numbers of 300+ W/m^2 are measured amounts and not derived amounts.
I was under the impression that the heat energy moved to the atmosphere via latent heat and thermals was kinetic and not radiative; and subsequently returned as kinetic in equal and opposite amounts. Is that not true?
10
The back radiation numbers are not measured, but derived from other measured values (after a boatload of assumptions). Actual measurements would require gridded data covering the entire planet looking up from the surface. The closest we have to this is the 25 year satellite record looking down, which is the data I started from.
Thermals are half of a vertical circulation current, where peripheral cold air sinks to fill the vacuum left from warm air rising. In principle, this is no different than any other circulation current in the atmosphere, which are not similarly considered as sources of power for the purpose of calculating net power fluxes between the surface, atmosphere and space.
Latent heat stays with the water as it ultimately condenses and falls as rain. The condensed water may radiate some of this energy away as black body radiation, but to the extent that latent heat replaces surface heat as it leaves the planet, surface heat is replacing latent heat as it’s being returned to the surface.
00
Thanks, that makes sense. As you’ve stated the Trenberth paper is often ambiguous and weak on details.
The bottom line though is for COE to be met in the system, ALL the post albedo power at the surface (239 W/m^2 of the total 385 W/m^2) has to come directly from the Sun, right?
00
RW,
Not necessarily directly. For example, the atmosphere/clouds may absorb some solar power and re-radiate it back to the surface, but generally, measurements of albedo implicitly includes the indirect effects.
00
co2isnotevil @ 256
“The back radiation numbers are not measured, but derived from other measured values (after a boatload of assumptions).”
Actually, they are directly measured (pyrometers, FTIR spectrometers, etc.) from multiple locations (first measurements were made by about 1954, can’t lay my hands on that paper at the moment), and are continually remeasured. That’s where you get the surface spectra graphs seen in many papers discussing back-radiation.
And given those measurements, correlated to humidity, cloud cover, and air temperature, those values are then extrapolated to the planet. But they are directly measured in multiple locations.
You can do the same yourself – point an IR thermometer up at the sky, just not up at the sun. The reading you get is from back-radiation.
00
In regards to thermals and latent heat – these transfer heat from the surface to the middle and upper atmosphere, supplying a fair bit of the energy emitted from the atmosphere to space.
Warm air rises, cool air drops – the energy from the warm air has been transferred up to the atmosphere.
Water vapor rises, cools, drops as precipitation – the energy of condensation has been transferred up to the atmosphere.
Descending cool air and precipitation have less energy than rising warm air and water vapor – the heat does not stay with the water or air when it descends.
And that energy leaves to space via thermal radiation, providing a cooler region (atmospheric lapse rate) for the water vapor and rising warm air to chill in. Otherwise we would have infinite energy building up in the atmosphere!
—
This is all part of solar energy coming in, and leaving via various pathways – direct IR from the ground through the ‘window’, IR, thermals, latent heat to the atmosphere, IR from atmosphere to space.
00
KR,
Extrapolation and interpretation is the problem. For example, looking up during the day you will see both primary and secondary IR directly originating from the Sun. This is not ‘back radiation’, but forward radiation from the Sun. Trenberth likes to call this ‘back radiation’ in order to give the false impression that GHG’s radiate this much. What few measurements have been made are interpreted based on assumptions about what is being measured. Any extrapolations from such a sparse set of data will have error bars that are far too large to validate the Trenberth perspective. The thermodynamic approach I’ve used to determine the steady state response works exactly and doesn’t require any assumptions.
You are wrong about the energy not staying with the water vapor as it rises, although it is correct that some energy is radiated away as BB radiation from condensed water in the clouds. However, whatever is radiated away by water in clouds is not required to be directly radiated by the surface and into space and conversely, what isn’t required to be radiated by the surface into space is returned to the surface replacing the latent heat that would have otherwise returned with the water. My point is that the existence of water vapor doesn’t change the requirements for radiative balance, as illustrated by this article, and that it’s only purpose is to reorganize energy within the planets thermal mass, i.e. between the surface and clouds (the clear sky stores negligible energy) in order to make the surface appear from space as being colder than it really is (i.e. cloud tops are colder than the surface).
00
KR,
There’s another property of clouds that has interesting consequences. This is that the radiating surface of a cloud is more than twice as large as the radiating surface of the planet beneath it. Relative to radiative flux, clouds present an equivalent temperature of about 262K up and about 273K down, for a total of 582 W/m^2. If all of this power was emitted by a planar surface (for example, the Earth’s surface), the equivalent temperature of the cloud would be about 318K (45C, 113F). Clouds then operate as a surface power flux (equivalent temperature) reducer by converting the planar radiating surface of the planet into a radiating cloud whose surface area is about twice as large. We can see in this scatter diagram of cloud power vs. surface power over the last 25 years of monthly, gridded samples, that cloud power approaches half of the surface power.
http://www.palisad.com/co2/div2/se_ce.png
00
KR,
I think the point you’re missing is that it doesn’t matter how the energy moved around by latent heat and thermals manifests itself. The same amount that leaves the surface must be returned in equal and opposite amounts, therefore, the net flux at the surface related to these is zero which has no influence on the radiated surface temperature of the planet, which after all, is just a net flux itself. As such, including these in discussions about the planets energy balance whose purpose is to show surface temperature influences is misleading at best and more likely purposefully obfuscating.
00
The bottom line is that for COE to be met, whatever the surface power ultimately is, 239 W/m^2 (or 100% of the post albedo power) of it has to be from ‘forward radiation’ from the Sun; therefore, the remainder has to come from ‘back radiation’ from atmosphere. Correct?
00
By ‘back radiation’, I assume that means radiation that last originated from the surface. By ‘forward radiation’, I assume that means radiation that last originated from the Sun. Correct?
00
RW,
Yes, on both counts.
00
BTW, how much of the surface emitted power is geothermal? Is it even 1 W/m^2?
00
George,
I’ve been doing some more investigating on this topic. Apparently, Trenberth claims that not all the 78 W/m^2 designated as “absorbed by the atmosphere” gets to the surface (even indirectly), but I don’t see how his numbers work out and COE is met unless it does. Do you?
I also notice in table 2a in his paper, he lists ASR (absorbed solar radiation) for “this paper” as 239.4 W/m^2 with a “NET Down” of 0.9 W/m^2, which seemingly implies that all of the 239.4 W/m^2 ultimately gets to the surface one way or another, but he says this is not what it means – it’s only the “top of the atmosphere value” (whatever that means).
Also, I notice in your own paper, the ‘power in’ and ‘power out’ values are about 249 W/m^2 (not 239 W/m^2) and your calculated albedo average is 0.272 (1-0.272)*341.4 = 249 W/m^2 . What accounts for the extra 10 W/m^2? I presume all the ‘power out’ is LW, right? Furthermore, in table 2a in Trenberth’s paper, he lists an albedo of 0.308 for the “ISCCP-FD” and an outgoing LW of 235.6 W/m^2. Do you know what accounts for theses discrepancies? Is the ISCCP-FD different data? Maybe he’s using data from a different and shorter period of time?
In general on various blogs discussions I’ve participated where this has come up there seems to be large disagreement on whether the full post albedo of 239 W/m^2 ultimately gets to the surface. Is there a way to empirically prove or demonstrate this?
00
RW,
Trenberth fails to distinguish between the clear sky and the cloudy sky. Clear sky absorption of solar power is negligible. Most of the post albedo incident power does that does not make it to the surface directly is absorbed by clouds, Half of this flux will be directed towards the surface and half will be directed back out into space. In principle, clouds are just an extension of the planets thermal mass, so power absorbed by them is equivalent to power absorbed by the oceans, relative to the planets steady state response to solar power.
I also agree that Trenberth’s picture doesn’t really balance. He inappropriately mixes radiative power with kinetic power, when the only thing the kinetic power does is reorganize the energy within the planets thermal mass. Radiative power is all that matters relative to the planets radiative balance and in that respect, his picture is out of whack.
The albedo I calculate is the net sum of the reflectivity of each 280 km square region of the planet based on ISCCP calculations. I’ve considered the 30% average albedo often quoted as a rough estimate since the actual albedo varies over a wide range during the year (snow/ice reflects more) plus there’s seasonal variability in cloud cover. It’s often assumed that the hemispheric variability cancels, but the hemispheres respond quite differently to seasonal change owing mostly to the amount and distribution of land and water. There’s some uncertainty in my calculations of cloud reflectivity, as I had to reverse engineer this from the optical depths reported in the ISCCP D2 data set, so I could be underestimating the power reflected by clouds and overestimating the power absorbed by them. I’m in the process of fixing this by redoing the analysis using the raw satellite radiances reported in the DX data set, which can produce planet reflectivity more directly and at a finer resolution.
The ISCCP FD data is even more highly processed than the D2 data and mostly reports anomalies against multi-year seasonal means. When you do this, the extents of natural seasonal variability become obscured loosing the information which contrasts the size of an anomaly with natural variability. It’s also not clear that the ISCCP FD reports of outgoing LW are in line with the actual visible albedo, unless albedo is estimated from the estimated outgoing LW, rather than being measured more directly.
George
00
Just out of curiosity, how do you think Trenberth is coming up with the figure of 78 W/m^2 “absorbed by the atmosphere”. The paper seems awfully sketchy on this, and the figure seems very high to me. Is perhaps a good amount of the post albedo absorbed into kinetic energy by the condensed water molecules in clouds and falling to the surface in the form of precipitation?
00
I would be very curious to see if there are any significant differences in your re-analysis of the data.
I also notice that the ‘power in’ and ‘power out’ numbers are almost exactly equal. How confident are you in these figures being accurate, at least relative to each other? This would appear to directly contradict the claim of energy accumulating somewhere in the system, which is why I ask.
Also, I notice the plots show an average surface temperature of 289K (not 287K). To get your average surface gain of about 1.6 are you dividing 396/249 to get 1.59? What accounts for the difference of 2K in the average temperature? The ISCCP Data? Something else?
00
RW,
I expect there to be some differences, but mostly minor. The biggest difference will be that I will correct the cross satellite calibration issues that makes the data useless for establishing trends. Remember these plots?:
http://www.palisad.com/co2/temp.gif
http://www.palisad.com/co2/temp_fb.gif
The first shows the published ISCCP data and as you can see, there is a discontinuity in late 2001 caused by the changeover from NOA-14 to NOA-16. It shows that the average temperature is about 289K. It drops to about 287.5K when the post 2001 bias is removed, although the corrected plot still uses the old average of 289K.
The bottom line is that relative to temperatures, there’s about 2C of anomaly caused by bad processing which interferes with attempting to establish a trend. This points out the basic problem with anomaly analysis where it can’t distinguish between an anomalous trend and anomalous (i.e bad) data.
George
00
George,
How much of the post albedo absorbed by clouds do you think actually gets re-emitted in the atmosphere? Is it reasonable to think a lot of it ends up getting to the surface in kinetic form via precipitation? If this were true – given that the Earth is 2/3rds clouds, I suppose Trenberth’s number of 78 W/m^2 might not be that far off?
If I’m understanding you correctly, it seems like you’re saying that clouds are really just mainly an extension of the surface ocean waters where energy in the form of latent heat of water is lifted from the oceans into the atmosphere, where it eventually condenses to form clouds and ultimately is precipitated back to the oceans. So in effect, any solar energy absorbed and not re-emitted by clouds is essentially the same as solar energy directly absorbed by the oceans?
00
George (RE: 272),
I see, yes. It also looks like the corrected data even shows a slight cooling trend from 1983-2008, which is interesting.
00
Little of the solar power absorbed by clouds is returned as the kinetic energy of rain. Solar power absorbed by clouds is similar to solar power absorbed by the ocean as both as part of the thermal mass of the planet. Solar, but mostly radiated surface power warms the water in clouds, which then radiates it away as a gray body flux back to the surface and out into space. Clouds have somewhat more incident flux than the surface, but appear much colder because the radiating surface of a cloud is twice that of the surface beneath it (i.e. for the same reason we divide the solar constant by 4).
The primary source of the kinetic power driving weather is the latent heat of evaporation, most of which is returned to the surface kinetically. While it’s entirely possible that the energy from a photon of solar power gets returned to the surface kinetically, for example, heating rain which falls to the surface, an equal amount of kinetic energy must be converted into radiative power in order to maintain balance. Some of the latent heat goes in to warming the water droplet as it condenses, some goes in to the gravitational potential energy of water lifted against gravity and the rest goes in to the kinetic energy of motion associated with the condensed water. Of these, the radiating, warned water is the relevant conversion process to offset any solar power returned to the surface kinetically.
George
00
George,
The main context of where I’m coming from with these questions is regarding the full post albedo (239 W/m^2) ultimately getting to the surface, which seems to be vehemently disputed by many, including Trenberth himself. I’ve spent some more time thinking about it and I’m still not quite sure I fully understand it.
I suppose even in a simpler sense that any of the post albedo that is absorbed by clouds and ultimately radiated out to space without ever reaching the surface just offsets energy from the surface that would otherwise have to leave the system?
I guess the bottom line is about 239 W/m^2 enters the thermal mass of the planet and becomes 385 W/m^2 emitted at the surface, with 239 W/m^2 leaving. Since all the energy at or below the surface originated from the Sun (excluding an infinitesimal amount from geothermal), COE dictates the net equivalent of 146 W/m^2 of radiative power must be coming back from the atmosphere in some form or another, and 146 W/m^2 must be radiated out to space?
I think one of the reasons why so many seem to be confused by this and/or find it difficult to fully grasp (including me) is that it in many ways seems counter intuitive. I’m pretty sure I understand completely the idea of the surface trading off non-radiative for radiative power – meaning if there is net kinetic energy loss from the surface to the atmosphere, this just offsets energy that would otherwise need to be radiated from the surface. Where still some confusion lies – for me at least, is in regards to the full post albedo of 239 W/m^2 getting the surface (directly or indirectly).
00
If the 239 W/m^2 of post albedo power is not entering the system, then it’s being ‘reflected’ and should be counted in the albedo. Whether it’s absorbed and ultimately radiated by the surface or clouds doesn’t matter for the radiative balance but does matter relative to understanding how the climate operates. I think what makes it confusing is that the surface is neither an input or output of the system, but a boundary dividing the planets thermal mass with highly chaotic fluxes passing across it. The chaos makes it seem complex, except that the integration of this flux over 4 seasons must be zero! Any long term non zero flux between the surface and atmosphere would cause one to endlessly warm or cool with respect to the other.
george
00
George (RE: 277),
Do you mean outgoing power in the LW infrared that does not ‘enter’ the system should be included in the albedo? This is crux of where the remaining confusion lies for me. What specifically is meant by ‘entering the system’? The clear sky atmosphere itself is part of the thermal mass of the system too (however tiny), so what’s the difference between solar power absorbed by it or clouds where some from each is radiated back out to space without ever reaching the surface?
This part – at least for me, is very easy to understand. 385 W/m^2 is just the net energy flux at the surface or just the net result of all the numerous ‘chaotic fluxes’ to and from the surface.
00
RW,
The original concern was that not all of the post albedo 239 W/m^2 reaches the surface. I claim this is moot because it all enters the system. What I mean by this is that all 239 W/m^2 is absorbed by the thermal mass of the planet. Certainly some is absorbed by clouds and a tiny amount is absorbed by the rest of the atmosphere, and in both cases, half of is sent to the surface anyway. The largest fraction is absorbed by the oceans which comprise most of the planets thermal mass. The oceans and clouds are thermally connected by water acting as the refrigerant in a heat pump linking them and which produces weather. In more precise gridded calculations, I analyze land, oceans and clouds in measured proportions and fully account for the power entering and leaving all components. However, it’s sufficient to consider an equivalent global model with a homogeneous thermal mass whose surface absorbs all 239 W/m^2 and whose average temperature over a year will be approximately equal to the actual average surface temperature of the planet. This correspondence is nearly exact because most of the planets thermal mass is below the actual surface, approximating the equivalent model.
George
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What about the part that the half absorbed by the atmosphere emitted back out to space should be included in the albedo as ‘incremental reflection’? I presume this power would be in the LW infrared? What specifically do you mean by this, and how can such power be differentiated from that which enters the thermal mass of the atmosphere, half of which is absorbed is emitted back out to space?
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Put another way, how can power be absorbed by the atmosphere and not be entering the thermal mass? Isn’t power absorbed by the atmosphere by definition entering thermal mass since the atmosphere is part of the thermal mass?
Perhaps you can clarify specifically what you mean by “Any solar power absorbed by the atmosphere will have half directed back into space and which is considered as incremental reflection and included in the albedo. That returned to the surface is included in the 239 W/m2.”
This seems to conflict with what you’re saying, which is that the full 239 W/m^2 does not have to get to the surface because the atmosphere (mainly clouds) is just an extension of the oceans. This is what is causing the confusion for me. I understand fully that your model is not a model of the actual behavior, but the net result equivalent of the actual behavior at the boundaries of the surface and the TOA. But it’s been my understanding that the full 239 W/m^2 needs to get to the surface one way or another in order for the model to work as depicted, but now you seem to be saying that isn’t the case.
Are you saying that power absorbed by the atmosphere and re-emitted to space without ever reaching the surface is trading off power that would otherwise have to leave the system from power that is emitted from the surface?
If yes, how does this apply to the model as far as half up/half down is concerned?
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BTW, I presume the IPCC is claiming the 3.7 W/m^2 is the equivalent of 3.7 W/m^2 of post albedo from the Sun, correct? Or not? Do they even make any such distinction? Now that I think about it more, I’m not sure they even do.
If they are claiming all of it ‘affects the surface’ then by definition all of it has to be going to surface too, right? After all, if it’s not all getting the surface, how can it all be increasing the surface temperature?
I also presume they are getting the often referenced 1.1 C from 2xCO2 by multiplying the 3.7 W/m^2 by the reciprocal of the planet’s emissivity of 0.612 (1/0.612)*3.7 = +6.04 W/m^2 at the surface, which from S-B equals about +1.1 C. The difference of 2.3 W/m^2 is the additional amount more the surface has to warm up to allow the 3.7 W/m^2 to leave at the TOA to restore equilibrium (239 W/m^2 in and out), correct?
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Looked at from another angle, if 239 W/m^2 does not ultimately get to the surface, then wouldn’t more than 146 W/m^2 of the 385 W/m^2 emitted at the surface need to be coming back from the atmosphere?
Let’s say hypothetically for example, 200 W/m^2 of the 239 W/m^2 gets to the surface one way or another. In this case, 185 W/m^2 is required to be coming back from the atmosphere instead of 146 W/m^2. The remaining 39 W/m^2 from the Sun is the half absorbed by the atmosphere and radiated back out to space without ever getting to the surface, making only 107 W/m^2 of the 292 W/m^2 going to space, which is less than half.
But I can clearly see from here (http://www.palisad.com/co2/div2/se_ce.png) that even when absorption is 100%, half is still escaping to space. So what am I missing?
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The divide by 2 applies to the top radiative balance, but included in this is the power radiated by the water in clouds absorbing solar power. Absorbed incident power warms the water in the clouds which falls as rain before it’s lost much of it’s gained energy through thermal radiation, thereby transferring the remainder wholly back to the surface. This is what I mean when I say that the clouds are thermally connected to the oceans. Adding heat to one has nearly the same effect on the energy balance as adding heat to the other. The surface temperature is minimally affected because it’s a far larger fraction of the thermal mass.
The IPCC’s 3.7 W/m^2 is the outgoing power deficit at the top of the troposphere (hence the language Trenberth uses). There are no clouds and little absorption between the top of the troposphere and the top of the stratosphere, so if the Sun got 3.7 W/m^2 warmer, it would have the same effect. You’re right that they don’t spell this out, which seems deceptive.
The reciprocal of the emissivity is what I call the closed loop surface gain and already includes the net effects of all feedback acting on the open loop gain. Multiplying the forcing by this and calling it ‘pre feedback’ is either out of ignorance or purposefully deceptive.
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OK, if I’m understanding it correctly, this makes more sense then. So A=292 includes any solar power absorbed by the atmosphere, and any absorbed solar power in the atmosphere that is radiated out to space is just offsetting radiative power from the surface absorbed by the atmosphere that would otherwise have to be leaving the planet?
So it’s not really half up/half down relative to surface emitted, but relative to the thermal mass as a whole, which includes the atmosphere?
So it’s not equivalent to post albedo power (i.e. 239 W/m^2 + 3.7 W/m^2), but rather 341.5 W/m^2 + 3.7 W/m^2? Boy, that is really ambiguous. I presume also they probably don’t even say how the 3.7 W/m^2 actually gets to the surface, do they?
In reality, the 3.7 W/m^2 number is the reduction in ‘window’ transmittance through the whole atmosphere, which includes the surface to space, cloud tops to space and the atmosphere itself to space, correct?
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This is because the planet’s emissivity already includes the lion’s share of the feedbacks in the system from decades and/or centuries of solar forcing, correct? The net negative feedback operating on the open loop gain as a whole means increased temperatures are being opposed, meaning the net response will likely be less than the gain as whole (not more), right? The idea here being the measured open loop gain response of about 1.6 is a representation of an upper limit, because the net feedback is negative rather than neutral or positive?
Also, the emissivity is just the post albedo power divided by the surface power (239/385 = 0.62 or 239/390 = 0.612), and this just means that for each 1 W/m^2 emitted at the surface, 0.62 W/m^2 (or 62%) escapes to space and 0.38 W/m^2 (38%) is returned to the surface one way or another?
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I wrote:
What I mean here is that 239 W/m^2 from the Sun is ultimately getting to the surface by trading off radiative power that would otherwise have to leave the planet with radiative power absorbed by the atmosphere from the Sun that does leave the planet without ever reaching the surface. So in effect, 239 W/m^2 gets to surface by way of requiring less of what’s absorbed by the atmosphere from the surface to be emitted to space?
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Or that energy absorbed by the atmosphere that last originated from surface or the Sun is the same, at least relative to the radiative balance?
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I just realized something else. If the IPCC is claiming the full 3.7 W/m^2 is getting to the surface to affect its temperature, how can they also claim the full 239 W/m^2 from the Sun is not ultimately getting to the surface too? That seems like a direct contradiction to me, yet it seems to be what they are claiming.
The more I think about this, the more amazed I become at what they have actually been able to get away with.
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George,
FYI, Trenberth just now has a post article over at Skeptical Science for his global energy flows paper and diagram:
http://www.skepticalscience.com/Tracking_Earths_Energy.html
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RW,
Yes, for most of your questions. The IPCC actually claims that the 3.7 W/m^2 deficit at the top of the troposphere results in a 16 W/m^2 increase at the surface (a 3C rise).
I can’t seem to post to the SS site. I didn’t think Cook was blocking me. I’ll have to try from work. I know he can’t block that one …
Feel free to post these, since it looks like you can post over there.
Trenberth claimed,
This is incorrect. Moving air of different temperatures and moisture content around has no influence on the radiative balance. It just changes which parts of the planet appear warmer and which appear colder from space. The total emitted to space doesn’t change. The radiative balance is maintained by adjusting the relative proportions of warm surface power and cold cloud power seen from space by varying cloud coverage.
He also claims that latent heat is returned as ‘back radiation’, when most is returned kinetically, either as the potential energy of water lifted against gravity, as heat returned to the surface by rain and as weather (wind, lightning, etc.). Similarly, thermals are claimed to return as ‘back radiation’, when a column of warm rising air in one place is eventually offset bo cold air falling in another.
George
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George,
Maybe your posts will show up later? Hasn’t that happened before? At any rate, if you’re ultimately unsuccessfully posting there, let me know.
I posted a few questions of my own in the thread, though I’m not sure Trenberth has any intention of participating in the discussion comments. We’ll see. I’d certainly be interested in hearing his responses to a lot of your stuff.
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Here’s my post to the Trentbert’s SS article. It seems that Cook is scared by the truth and deleted it. I’ve also resent it to Trentbert via private email.
Kevin,
You claim that, “The differential between incoming and outgoing radiation: the net radiation is generally balanced by moving air of different temperature and moisture content around.”
This is incorrect. Moving air of different temperature and moisture content around has no influence on the radiative balance. It just changes which parts of the planet appear warmer and which appear colder from space. The total emitted to space doesn’t change. The radiative balance is maintained by adjusting the relative proportion of warm surface power and cold cloud power as seen from space by varying cloud coverage. These 3 views of the ISCCP data illustrate how this works. The first is cloud percentage vs. surface temperature, the second is atmospheric water content vs. surface temperature and the last is the cloud coverage vs. atmospheric water content. All plots are scatter diagrams of almost 3 decades of monthly averages for each 2.5 degree slice of latitude. Let me know if you need help interpreting this data.
A misleading aspect of your presentation is that you’re not clearly distinguishing between the effects of clouds and the effects of the clear sky. Most of what you attribute to the atmosphere can be attributed to clouds. Your presentation may mislead the less informed into believing that atmospheric absorption is a bigger contributing factor than it really is.
Another misleading point is that thermals are half of a kinetic vertical circulation and lumping in the return path with ‘back radiation’ is both inaccurate and misleading. Your treatment of latent heat suffers from the same error. For example, the potential energy of water lifted against gravity (hydro) arises as water vapor adiabatically expands against an atmospheric density profile established by gravity. It’s also returned as the kinetic (wind) and electrical (lightning) energy of weather. Whatever’s left is returned to the surface as the temperature component of rain. The point being that the latent heat mostly stays with the water through it’s circulatory path. Along the way, the water will radiate some away, both into space and back to the surface, but much of what is radiated away is replenished by energy from the Sun or surface subsequently absorbed by the atmospheric water.
George White
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George,
At SS, you’re not allowed to accuse anyone of intentionally misleading or deceiving. It’s the first rule of the comments policy. If you try re-wording your comments, they will probably be allowed.
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I tried a few tweaks, but no post. To think that I once gave SS credit for having a less fascist censoring policy than most warmist sites. My opinion certainly has changed. I tried this next post in response to a series of posts expounding hidden heat and it was summarily dismissed as well:
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George,
I’m pretty sure I get it now. I was over thinking it. All that is happening is post albedo power from the Sun absorbed by the atmosphere is just trading off surface emitted power absorbed by the atmosphere that would otherwise be leaving the planet.
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George (RE: 295),
So what you’re saying here is “missing heat” is impossible because the delayed exit of surface energy is too short live for energy to accumulate in the thermal mass – at least long enough to ‘hide’ heat for multiple years or decades?
Are you basing this primarily on the physics of energy flow in and out of the system or more on the measured data from ISCCP where no total “power in, power out” imbalance is found?
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I’m now being censored too at Skeptical Science.
I posted the following response Trenberth’s response to me and it was deleted:
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George (RE: 293),
I just sent mine to Trenberth directly also. BTW, did he ever respond to you?
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Trenberth did respond to me, but his responses are bizarre. I’m not sure I even understand most of them.
On another note, I ran some of Trenberth’s figures using a ‘window’ transmittance of 82 W/m^2 which gives exactly half up/half down with his numbers (instead of the 70 W/m^2) and using the ISCCP averages of 66.7% clouds and 33.3% clear sky, it gives virtually exact output of 239 W/m^2 depicted in his diagram.
Is this just a coincidence, or is there a reason for this? I increased the window through the clear sky by a 1/3rd to 44 W/m^2 and 2/3rds through the cloudy sky to 38 W/m^2. I don’t know if this a reasonable estimate or not.
I know you have shown how clouds control the energy balance, but you used cloud tops to space absorption from average cloud power – not from the surface through the clouds. Is there a difference fundamentally?
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I guess it’s probably a coincidence since I used the 1/3rd clear and 2/3rds cloudy to get the average absorption figures for each, which I then divided by 2. By starting with a window that gives half up and half down, the output would have to equal 239 W/m^2 if energy is conserved.
I get about 231 W/m^2 leaving with the 70 W/m^2 ‘window’ if I divide the aborption by 2, which I guess makes sense since he has more than half leaving.
Is there a way using Trenberth’s numbers to show roughly how clouds are controlling the energy balance? I prefer to use the warmers’ own numbers when ever possible since most are familiar with the paper and diagram.
If you’re getting about a 40% absorption from the cloud tops to space, how much of that is passing through the ‘window’? Is it even anywhere near 30 W/m^2 depicted by Trenberth?
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George,
I just noticed that Gavin’s own model and formula of the atmosphere at realclimate.org has half of what’s absorbed by the atmosphere going to space and half going back to the surface:
http://www.realclimate.org/index.php/archives/2007/04/learning-from-a-simple-model/
His formula is the net surface radiative flux ‘G’ = post albedo solar flux ‘S’/(1-0.5ƛ) where ƛ = the surface to space absorption (your A).
Did you ever take him to task on this?
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RW,
Schmidt censors any post where I would take him to task on anything, so I no longer bother. Speaking of which, his principle argument against the recent paper by Spencer and Braswell was that albedo variability is not ‘forcing’. In the paper, “On the misdiagnosis of surface temperature feedbacks from variations in earth’s radiant energy balance”, they show how natural variability affects albedo which is like forcing (per the IPCC definition) and which must be removed from the signature before you can use satellite measurements to quantify the sensitivity of the Earths surface temperature to radiative forcing.
I’d be happy to agree with him about the nature of his objection, if he would agree that for the same reasons, incremental CO2 (which effects emissivity) and incremental aerosols (which effects albedo) are also not forcing factors. Of course, I don’t agree that this specific objection falsifies S & B, in fact, this specific objection is why the S & B hypothesis is correct, that is, there’s a misdiagnosis. What it boils down to is the definition of forcing. From a control theory perspective, only the energy entering the system is considered forcing. The rest of the factors change the system, affecting its response, but do not change what’s forcing the system to respond.
Technically speaking, Schmidt is correct, at least in the context of control theory, however; this precludes considering incremental atmospheric absorption, areosols and natural variability driven by fluctuating albedo (clouds) as forcing quantities as well. The IPCC’s definition of forcing differs from the proper control theory definition and among the things it includes, it should include natural albedo variability, but does not. It seems that Schmidt is trying to have it both ways.
PS. I’ve gotten several, mostly useless, responses from Trenberth. Like the rest of them, he can’t justify himself with actual science. Also, the difference between cloud to space and surface to space atmospheric absorption is a result of the much less water vapor (nearly 0) above the cloud tops.
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George,
I’m not surprised. In his responses to me he actually claimed that most of the 78 W/m^2 ‘absorbed by the atmosphere’ was by water vapor and aerosols – not clouds.
He could not or did not answer the question regarding the origin of the energy in the temperature component of precipitation and/or why this return path isn’t shown in his diagram.
He also acknowledged that post albedo energy ‘absorbed by the atmosphere’ can be traded off with surface energy absorbed by the atmosphere, but still insists the full post albedo does not get to the surface.
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I hadn’t realized the article on RC was written by Trenberth. That explains a lot. I read it a few days ago and it just seemed to be written in the condescendingly snarky tone of Schmidt and not by a ‘distinguished’ climatologist with a share in a Nobel prize for his work …
I posted this on RC, but it will probably not get past the moderator. Not because there’s anything that violates posting rules, unless one of those rules is that you can’t challenge the consensus.
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George,
I actually participated in that thread with a few exchanges, trying to get Gavin and others to see the solar forcing perspective on sensitivity. I think Gavin is past the point of no return, as are most of the participants there. As usual, they don’t seem to really be able to answer anything – they just talk around it or declare it wrong.
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BTW, maybe you’re post will go through. It’s been a few years since the last attempt, right?
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Your post actually just went through and Gavin responded.
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George,
In the numerous discussions I’ve had where this issue comes up, there seems to be such an enormous resistance to it, including from skeptics – many of whom vehemently insist it is wrong.
While I do clearly see that it is not entirely straight forward and requires some unconventional thought to understand, I’m wondering why you think there is such strong opposition to it? Having not been formerly trained in this, I’m a bit curious. Is it perhaps the way atmospheric physics and/or heat energy transfer is taught?
While I’m pretty sure I understand it now, and it’s obvious to me the purpose of it is to strip the system down to net energy flux, which is what really matters – I remain puzzled why so many who appear to be well educated and trained in physics oppose it.
Your thoughts?
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I’ve been having a conversation with Gavin about this and he insists it is wrong, so it seems there’s no way to make any headway. Curiously, when I ask if not 50/50 (half to space and half back to the surface) then what percentages and based on what physics and data, he and others don’t seem to be able to provide an answer.
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[snip], the scattering effect is nothing new. I’m not sure where you’d find the most accurate estimates of outgoing longwave radiation but harries et al (2001) might have some of what you’re looking for.
[either explain your position on the title or leave cheap shots out of your posts] ED
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George,
“What Trentbert fails to account for is radiation from the atmosphere (not just the clouds) that passes through the transparent window. When this is added back, 93 W/m^2 is the right value.”
I’ve noticed you referring here and elsewhere that part of the 93 W/m^2 of ‘window’ transmittance is that which is emitted by the clouds and by the heated atmosphere itself that passes straight into the space (in addition to that emitted from the surface that passes straight into the space).
What I don’t understand is how this emitted power can be differentiated from that which is emitted by clouds or the atmosphere itself that eventually passes into space as part of the 146 W/m^2 flux leaving at the TOA.
Unless I’m missing something obvious, it seems to me that the 93 W/m^2 has to be the total direct surface to space transmittance or the amount of surface power that passes straight to the space as if atmosphere wasn’t even there. Or about 43 W/m^2 passes from the surface directly through the cloudy sky to space and 50 W/m^2 passes from the surface directly through the clear sky to space.
Didn’t you calculate a direct transmittance from the cloud tops to space as something like 0.60, which would result in way more than 43 W/m^2 from the clouds, would it not?
Or am I missing something obvious?
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RW
You have just pointed out the key issue with this type of addition.
It is based on very simple analysis by people with very little physics and even less intention of letting it get in the way of a good story.
When you look at the size of the Total CO2 heat interaction effect and then extract the component related to human activity (about 3%), what you are dealing with is a very small quantity.
The reason that these analyses exist is because they need to cover over the inescapable basic physics that Human Origin CO2 is irrelevant to the Earth’s thermal cycle because of infinitesimally small size of contribution.
You will notice that ALL commentary from Warmers Never Extracts the Human Component of the effect; they just say “this is what CO2 does” and to add to the lie they even leave out other overwhelming components like WATER; now how could they have missed that.
Yes , it’s deliberate; very deliberate to the point of deception.
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It is based on very simple analysis by people with very little physics and even less intention of letting it get in the way of a good story.
For an example, see the title of this post.
Joanne hears that when GHGs absorb thermal radiation they emit the radiation in all directions (correct).
Joanne assumes this is a fundamental issue that scientists have overlooked in the GCMs (incorrect).
Next week: Evolution disproved, humans came from fish!
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“Next week: Evolution disproved, humans came from fish!””
Wonders of Nature EXPOSED!!
Hi Tristan. I love science and especially experiments.
Cup your hands and put one over each ear – that’s those funny things on the side of your head.
What do you hear?? Could it be the sound of …….the ocean.
An evolutionary echo; not surprising since our ears evolved from the ocean environment.
Amazing to think that our ears were once used to extract oxygen from the water before they got tired of being gills.
Back to the problem ; that of doing an energy balance on the earths atmosphere; so there are half a dozen factors listed in these sparse attempts to recreate nature.
It’s preposterous to think that someone like Trenberth is going to do one of these correctly given he will not include atmospheric friction , night / day variations, seasonal hemispheric switches, mass and momentum balances of every gaseous constituent of the atmosphere and allowing for variations due to land form shape and albedo , not to mention LH estimates for every ice melt and rain squal on the planet and difference of land vs water.
The big giveaway of a scam calculation is when I see people exactly balance their Energy Input with Energy Output.
Energy Input – Energy Output = Zero = Scam.
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Tristan,
“Joanne hears that when GHGs absorb thermal radiation they emit the radiation in all directions (correct).
Joanne assumes this is a fundamental issue that scientists have overlooked in the GCMs (incorrect).”
Perhaps then you can answer question that none of the detractors of this seems to be able to answer: If not 50/50 (half to space and half back to the surface) then what fraction and based on what physics? Surely not all of the surface LW flux absorbed by the atmosphere is emitted back down toward the surface, as this would imply that energy absorbed by the atmosphere from the surface LW flux never leaves the system, which is obviously not correct.
Even if you can’t agree that the split is 50/50, clearly the fraction of the absorption emitted to space cannot be considered equal to that coming down in from the Sun, right?
It is generally assumed by the IPCC and the climate science community that the 3.7 W/m^2 of so-called ‘forcing’ is equal to post albedo solar power, so if there is currently about 240 W/m^2 coming in post albedo from the Sun, a doubling of CO2 is supposed to be the equivalent of an increase to 243.7 W/m^2 of solar power entering the system. Correct?
In general, the way they’re calculating the so-called ‘zero-feedback’ response from 2xCO2 is by multiplying 3.7 W/m^2 of ‘forcing’ by the ratio of emitted surface radiative power to post albedo incident solar power, where 390/240 = 1.625 and 3.7 W/m^2 x 1.625 = +6.01 W/m^2, which equals about 1.1-1.2C of warming (from S-B).
So what say you, Tristan?
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If you’re referring to Spencer & Braswell’s 2011 paper, I say: Go ask here. Just remember to be polite. 🙂
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Tristan,
I’m not referring to S&B 2011.
[typo corrected]
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Hi RW and Tristan
Do you guys have any idea of the path-length traveled by the radiation in question.
You may be surprised!
The path length is so short that discussions of up down sideways or whatever are irrelevant.
The radiation is re emitted essentially right where it was absorbed.
Then – convection or finally radn to space.
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KinkyKeith,
I would imagine it’s often quite short, at least closer to the surface, and no doubt there are multiple absorptions and re-emissions; however, the path-length doesn’t matter because we know the radiation eventually escapes into the space as part of the 240 W/m^2 flux leaving at the TOA.
Is there any doubt that the 150 W/m^2 emitted from the atmosphere that passes into space can only be from the upward half of the isotropic emission in the atmosphere?
Also, is there any doubt that all the radiative emission in the atmosphere, on a photon by photon basis, is isotropic?
The surface is cooler and subsequently radiates less as a result of convection in the atmosphere, which increases the rate at which the system can cool and/or ultimately emit energy back out into the space (i.e. there is a net convective loss from the surface to the atmosphere). But power convected from the surface that ultimately ends up radiated out at the TOA, offsets additional power that would otherwise have to be radiated from a warmer surface. It doesn’t affect what fraction ultimately goes to space and what fraction goes back to the surface, relative to radiative flux boundaries of the surface and the TOA, where at the TOA only radiation enters and leaves.
00
“because we know the radiation eventually escapes into the space ”
Hi. The point is that eventually all of the radiation is pushed out into space.
The question of how fast at any particular moment is a function of the quantity of energy rising from below.
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I have to admit that when I first became aware of this over a year ago, I have gone back and forth several times as a result of all the investigation and numerous discussions I’ve had on it, but I’m now thoroughly convinced the 50/50 split, as depicted by George, is correct.
Ultimately, the questions that I can’t reconcile, if George’s model or paper is to be falsified, are:
Can any of you detractors out there answer ‘no’ to any of these questions? I can’t.
Also, if the atmosphere cannot create any energy of its own, and as a result 240 W/m^2 must arrive at the surface directly or indirectly from the Sun, what is the origin of the +150 W/m^2 flux into the surface? If not from the downward emitted half of the re-emitted power absorbed by the atmosphere from the surface LW flux, then where is it coming from?
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Hi Rw
I used to get involved in this type of micro-assessment of the system but it countered my training in setting up the problem ready for analysis.
I was trying to understand how other people saw the problem and it became obvious that they had no basic training in solving the type of problem at hand ie Extremely Complex Interactive Systems – that’s my training.
Listing a series of questions, as above, is getting too close – it is necessary to step back and define the situation from an overall perspective ie. include all factors in the solution.
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KinkyKeith,
“The point is that eventually all of the radiation is pushed out into space.”
I know, but since the surface cannot warm unless it receives more energy, the net energy flux back into the surface from that absorbed by the atmosphere, from additional GHG ‘forcing’, is what matters in this case.
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The hottest point during the day is earths surface. Space is -270.46 deg C not quite absolute zero.
Heat will only, can only follow the temperature gradient.
Once heat has left the earth it don’t come back.
“Forcings” are a tool of warmer U
That model is wrong.
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KinkyKeith,
“Heat will only, can only follow the temperature gradient.
Once heat has left the earth it don’t come back.”
Radiative power doesn’t contain heat, as by definition radiant energy in and of itself has no temperature.
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I should perhaps more correctly say that radiative power or radiant energy doesn’t have a temperature.
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OK
The energy then.
You can’t have temperature without thermal energy.
In terms of what physically happens – does it make a difference?
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KinkyKeith,
“The energy then.
You can’t have temperature without thermal energy.
In terms of what physically happens – does it make a difference?”
Yes it does because radiant energy (photons) can travel from the colder atmosphere toward the warmer surface. If you doubt this, how does the radiant energy from the Sun entering at the TOA travel from the colder upper atmosphere to the warmer surface?
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Hi RW
Going rund in circles here man.
Heat cannot flow uphill.
Go back to my post about path-length.
YES I AGREE
Radiation goes towards Earth — But it never gets there
Think about path length and gas theory.
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Long live convection.
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KinkyKeith,
“YES I AGREE
Radiation goes towards Earth — But it never gets there”
You’ve never felt the Sun’s rays on your skin when you walk outside?
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