Heh. In response to a ridiculous claim making the rounds (I get comment bombed at WUWT daily with that nonsense) which I debunked here: A misinterpreted claim about a NASA press release, CO2, solar flares, and the thermosphere is making the rounds
Dr. Roy Spencer employs some power visual satire, that has truth in it. He writes:
How Can Home Insulation Keep Your House Warmer, When It Cools Your House?!
<sarc> There is an obvious conspiracy from the HVAC and home repair industry, who for years have been telling us to add more insulation to our homes to keep them warmer in winter.
But we all know, from basic thermodynamics, that since insulation conducts heat from the warm interior to the cold outside, it actually COOLS the house.
Go read his entire essay here. <Sarc> on, Roy!
UPDATE: Even Monckton thinks these ideas promoted by slayers/principia/O’Sullivan are ridiculous:
Reply to John O’Sullivan:
One John O’Sullivan has written me a confused and scientifically illiterate “open letter” in which he describes me as a “greenhouse gas promoter”. I do not promote greenhouse gases.
He says I have “carefully styled [my]self ‘science adviser’ to Margaret Thatcher. Others, not I, have used that term. For four years I advised the Prime Minister on various policy matters, including science.
He says I was wrong to say in 1986 that added CO2 in the air would cause some warming. Since 1986 there has been some warming. Some of it may have been caused by CO2.
He says a paper by me admits the “tell-tale greenhouse-effect ‘hot spot’ in the atmosphere isn’t there”. The “hot spot”, which I named, ought to be there whatever the cause of the warming. The IPCC was wrong to assert that it would only arise from greenhouse warming. Its absence indicates either that there has been no warming (confirming the past two decades’ temperature records) or that tropical surface temperatures are inadequately measured.
He misrepresents Professor Richard Lindzen and Dr. Roy Spencer by a series of crude over-simplifications. If he has concerns about their results, he should address his concerns to them, not to me.
He invites me to “throw out” my “shredded blanket effect” of greenhouse gases that “traps” heat. It is Al Gore, not I, who talks of a “blanket” that “traps” heat. Interaction of greenhouse gases with photons at certain absorption wavelengths induces a quantum resonance in the gas molecules, emitting heat directly. It is more like turning on a tiny radiator than trapping heat with a blanket. Therefore, he is wrong to describe CO2 as a “coolant” with respect to global temperature.
He invites me to explain why Al Gore faked a televised experiment. That is a question for Mr. Gore.
He says I am wrong to assert that blackbodies have albedo. Here, he confuses two distinct methods of radiative transfer at a surface: absorption/emission (in which the Earth is a near-blackbody, displacing incoming radiance to the near-infrared in accordance with Wien’s law), and reflection (by which clouds and ice reflect the Sun’s radiance without displacing its incoming wavelengths).
He implicitly attributes Margaret Thatcher’s 1988 speech to the Royal Society about global warming to me. I had ceased to work with her in 1986.
He says that if I checked my history I should discover that it was not until 1981 that scientists were seriously considering CO2’s impact on climate. However, Joseph Fourier had posited the greenhouse effect some 200 years previously; Tyndale had measured the greenhouse effect of various gases at the Royal Institution in London in 1859; Arrhenius had predicted in 1896 that a doubling of CO2 concentration would cause 4-8 K warming, and had revised this estimate to 1.6 K in 1906; Callender had sounded a strong note of alarm in 1938; and numerous scientists, including Manabe&Wetherald (1976) had attempted to determine climate sensitivity before Hansen’s 1981 paper.
He says, with characteristic snide offensiveness, that I “crassly” attribute the “heat-trapping properties of latent heat to a trace gas that is a perfect energy emitter”. On the contrary: in its absorption bands, CO2 absorbs the energy of a photon and emits heat by quantum resonance.
He says the American Meteorological Society found in 1951 that all the long-wave radiation that might otherwise have been absorbed by CO2 was “already absorbed by water vapor”. It is now known that, though that is largely true for the lower troposphere, it is often false for the upper.
The series of elementary errors he here perpetrates, delivered with an unbecoming, cranky arrogance, indicates the need for considerable elementary education on his part. I refer him to Dr. Spencer’s excellent plain-English account of how we know there is a greenhouse effect.
The Viscount Monckton of Brenchley (April 18, 2013)
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Max, your Dyson Sphere would correspond to “Problem 1026”, not to “Problem 1023”. The results from Problem 1023 — where the shell is assumed to be “nearby” cannot be applied to the case of a Dyson Sphere where the shell is “far far away” from the sun.
So basically your entire set of conclusions are doomed before you even start.
Max™ says (April 25, 2013 at 4:39 pm): “Well, in my above Sun/1 AU radius Dyson sphere example, the sphere is gaining a net of 683 W/m² from the Sun and losing 683 W/m² to space, isn’t it?
Oh, I forgot, is it supposed to make the Sun hotter when it does that?”
Why do you think the sun wouldn’t absorb the incoming energy?
Look at the diagram for problem 1023. Do you see the J1 arrow pointing from the shell toward the inner sphere? What do you think happens to that J1 when it hits the inner sphere? Does it somehow disappear?
Max, you’re not having second thoughts about your own reference, are you?
tjfolkerts writes “Now bump the CO2 up to 400 ppm. There will indeed be more photons being created at 12 km altitude by more CO2 molecules. BUT less than 50% of them will escape to space because there are a lot more CO2 molecules above 12 km than there were before.”
Make the numbers easier. Bump the CO2 levels from 300ppm to 600ppm and now there are twice the molecules creating radiation at 12km altitude and twice the molecules above. My assumption is that is twice the opacity.
So twice the photons making their way through twice the opacity is an equivalent amount of energy leaving from the same altitude.
Your statement above “less than 50% of them will escape to space because there are a lot more CO2 molecules above 12 km than there were before” is correct. With a 33% increase in CO2 (300ppm to 400ppm), I’d expect 33% increase in radiation out at that same altitude. That is indeed less than half.
Where is this reasoning broken?
tjfolkertds says:
“…less than 50% of them will escape to space…”
That’s wrong. Due to the curvature of the earth, the higher the altitude, the more likely that 50%+ of all emitted photons will escape to space.
Molecular density does not matter, because it all averages out. Eventually, the last photon will either hit the surface, or go out into space. More than half of all photons will escape to space once the emitting molecules are any altitude above the surface.
Gedanken: Imagine a molecule at 25,000 miles altitude. The earth would appear as a distant ball. How many molecules, on average, will be emitted toward the surface from that altitude? Answer: far less than 50%
Climate alarmists are constantly trying to justify their belief that CO2 causes any measurable global warming. But the earth itself is proving them wrong. Who to believe? Earth? Or alarmists?
TimTheToolMan
With a 33% increase in CO2 (300ppm to 400ppm), I’d expect 33% increase in radiation out at that same altitude. That is indeed less than half.
Where is this reasoning broken?
>>>>>>>>>>>>>>>>>
It is broken on the assumption that increasing the concentration increases the radiation out from a given altitude. It doesn’t. Several people have responded explaining why.
TimTheToolMan says:
You are missing the whole point. The amount of energy leaving is not determined by this tradeoff between number and opacity. The amount of energy that a substance emits is determined by its temperature. For emission from the atmosphere, the opacity just determines where in the atmospheric column the emitted photons (i.e., those that successfully escape to space) come from. And, as the opacity increases, this emission has to occur at higher and higher levels of the atmosphere where, because of the lapse rate in the troposphere, it is colder and hence (by the Stefan-Boltzmann Law) less emission occurs.
And, this isn’t some sort of theoretical notion. It is FACT, verified by satellite observations ( http://www.barrettbellamyclimate.com/userimages/Iraq2.jpg ), and without it working as we understand it to work, the whole field of remote sensing would not be possible. It is, among other things, completely inconsistent to simultaneously hold the opinion that Spencer and Christy’s satellite measurements of the tropospheric temperatures have any validity and to believe that the greenhouse effect does not work in the way we are explaining it does. In fact, you can’t even really believe in the IR satellite photos that you see on the weather reports on TV without accepting these basics of radiative transfer in the atmosphere.
davidmhoffer writes “It is broken on the assumption that increasing the concentration increases the radiation out from a given altitude. It doesn’t. Several people have responded explaining why.”
No they haven’t. I expect we’ll both agree that increasing the concentration increases the radiation rate (both up and down) at that altitude. tjfolkerts seems to agree with that and its pretty basic physics.
But when it comes to how much gets past the increased opacity above, nobody has explained anything, They’ve simply stated that more CO2 above stops the radiation without addressing the fact there is more radiation trying to get through. Your post is no exception.
dbstealy, you are addressing a different issue. Geometry does indeed play a role in the fraction of the IR photons that are emitted “away from the earth”, and here molecular density does not matter. But even 20 km up, the horizon is only about 4.5 degrees downward.
But molecular density tells us if those photons emitted upward will indeed escape before hitting another CO2. Near the surface, 0% of the upward photons will escape.
(And now that I thin about it, the “nearly horizontal photons” are really not important. A photon that is heading “sideways” will go miles through “fairly dense CO2” and hence has a high chance of being absorbed. The photons heading “nearly vertical” will be heading straight for the thinner higher atmosphere and hence has a good chance of escaping. )
TimTheToolMan,
It is not obvious whether the increased emission or the increased absorption will be “stronger”. Let me give two “plausibility” arguments.
1) Increasing the concentration of CO2 near the surface will have no effect on the outgoing radiation, since 100% of the photons created from the thicker CO2 will be absorbed before escaping. Conversely, if you go way up high where 99% of the photons currently escape, the doubled concentration will double the created photons, but most (maybe 95%) will escape. So we now have ~ 1.9 times as many photons escaping form this altitude. Overall, this pretty clearly is raising the effective radiating level.
2) More detailed calculations like MODTRAN support the conclusion that more CO2 reduces the outgoing radiation. http://forecast.uchicago.edu/Projects/modtran.html
At this level of discussion, i am not sure there is a “better” answer than these.
[snip. ~mod.]
Insulation neither cools nor heats, it simply retards the transition from one state to the other. ie. Greatly slowing warming during hot weather and greatly slowing cooling during freezing weather.
“Why do you think the sun wouldn’t absorb the incoming energy?
Look at the diagram for problem 1023. Do you see the J1 arrow pointing from the shell toward the inner sphere? What do you think happens to that J1 when it hits the inner sphere? Does it somehow disappear?” ~Gary
I think it replaces some of the photons leaving the Sun, but I don’t think it is going to make any sort of noticeable difference, the Sun isn’t heated at the surface, after all.
The star is heated by the action deep inside, and the temperature of the outer layers is determined by the photons that spend ages trickling out from the interior where the fusion reactions take place, not photons that return from whatever is illuminated by the star.
…
A Dyson sphere as wide as our orbit around the Sun, at this distance it receives 1366 W/m², and it radiates half of that in and out, so you’ve got a shell of returning photons that started out at 683 W/m² making it back to the surface of the Sun.
That replaces half of what escapes the surface, and the other half escapes to space from the exterior of the shell, seems like the system would be in balance there.
J = 1366 W/m² | → |
J₁ = 683 W/m² | ← | →
Even if one were to argue that the Sun should heat up, what mechanism do you propose would do this? What imbalance would this be correcting? Wouldn’t that create a greater imbalance if the surface had to heat up until the exterior of the shell radiated at the same power as the surface originally did?
Heck, if the net Surface > Shell is 683 W/m², then wouldn’t the exterior already radiate at the same power when it emits 683 W/m² to space?
Your argument sounds reasonable, but I don’t see how you justify the “and then the surface heats up until the exterior of the shell emits as much as the surface originally did” step.
tjfolkerts writes “It is not obvious whether the increased emission or the increased absorption will be “stronger”.”
Thats the way I see it and I’m always skeptical of these kinds of blanket statements that cant be backed up with a reasonably straightforward physical explanation. This one (increased ERL with increased CO2) appears to rely on non-linearity in CO2 absorbtion with concentration, a non-intuitive result.
The ERL hand waving fails because the gases in our atmosphere move. Hot gases are radiating more strongly than the gases at the altitude they are rising through.
The AGW nonsense also fails because the gases in our atmosphere move. Climate pseudo scientists are rubbish at fluid dynamics.
TimTheToolMan;
They’ve simply stated that more CO2 above stops the radiation without addressing the fact there is more radiation trying to get through. Your post is no exception.
>>>>>>>>>>>>>>>>>>
But there isn’t.
There’s 240 w/m2 going in, and 240 w/m2 going out. Double the CO2. There’s STILL 240 w/m2 going in and STILL 240 w/m2 going out once equilibrium is re-established. There is NOT more radiation trying to get through.
Let me try and explain it another way. Suppose you have one row 4 of co2 molecules 1 meter above earth surface. Release 8 photons. 4 hit CO2 molecules, get absorbed, and re-emitted to space. The other 4 go straight on through. What is the effective radiating height?
4 escaped from ground which is zero, and 4 escaped from 1 meter. Average is 1/2 meter.
Now double the CO2. one row of 8. Release 8 photons, but now each and every one gets absorbed and re-emitted to space. Average emission height is now 1 meter. But there are still only 8 photons released.
Now think of that but with millions of layers. Any given photon might go just one layer before being absorbed and re-emitted, or it might go through several. It might get to space in 8 leaps straight up, or perhaps 4 up 3 down 1 up 2 down 6 up 1 down 3 up. Or millions of those. As the density of the CO2 molecules increases, the distance any given photon can travel before hitting a CO2 molecule goes down. The number of times any given photon will be absorbed and re-emitted before escaping will increase. The chances of any given photon escaping from a given altitude will be reduced at all altitudes, but will be reduced MORE the lower the altitude is.
So when CO2 doubles, you have a period where equilibrium is broken because any given photon has to make that many extra bounces up, down, and sideways until it escapes. But that’s temporary, the system re-established equilibrium with the exact same w/m2 coming in as before, and the exact same w/m2 leaving as before, but the place they leave from on average is a higher altitude.
davidmhoffer writes “Now double the CO2. one row of 8. Release 8 photons, but now each and every one gets absorbed and re-emitted to space. Average emission height is now 1 meter. But there are still only 8 photons released.”
The thing is that there aren’t 8 photon released when you double the CO2. There might be 8 released at at ground level, but up where ERL happens the radiation is supplied by the GHGs not the ground. So now there are 16 photons emitting from twice the GHGs that are ready to emit and the argument follows from there.
TimTheToolMan,
I think you’re missing Hoffer’s point [and mine]. The point is that when all is said and done, the average photon either heads for space, or hits the surface. It doesn’t matter if there are a dozen photons, or a zillion. Their final direction averages out.
The higher the altitude of emission, the more likely it is that any particular photon will head out to space. Simple as that. The curvature of the earth, along with the altitude, requires it.
richardscourtney says (April 25, 2013 at 3:15 pm): “So, insulation in the walls of a house raises the temperature in the house in the same basic way as greenhouse gases in the air raise the temperature of the Earth’s surface.”
==============================================================
This is so very wrong.
First, “greenhouse gases” in the air do not raise the temperature of the Earth’s surface, anyway not by radiating back radiation towards it, because such an effect of back radiation is physically absurd and therefore impossible, see my previous comments on this thread.
Second, insulation in the walls of a house prevents the air temperature in the house from increasing, decreasing or has no effect at all, depending on certain factors. Middle school stuff and practical experience of everyone.
In terms of insulation, the “greenhouse gases” only insulate the Earth surface from some portion of solar IR by blocking it. That is all. No warming of the surface by back radiation from “greenhouse gases” is possible.
dbstealy writes “The higher the altitude of emission, the more likely it is that any particular photon will head out to space.”
I agree with you. This discussion is about precisely locating the average height at which that happens and looking at what happens to that average height when the concentration of greenhouse gasses changes.
AGW theory relies on that height increasing so its an important point to understand.
TimTheToolMan;
The thing is that there aren’t 8 photon released when you double the CO2. There might be 8 released at at ground level, but up where ERL happens the radiation is supplied by the GHGs not the ground.
>>>>>>>>>>>>>>>
For the love of *** no!
ALL the photons are from the ground in the first place. You can double, quadruple or millionuple the CO2, ALL the photons in the system originate from the ground. All that changes is the number of times they bounce around before escaping. The GHG’s do not, I repeat DO NOT add additional photons to the system.
I’ll try again. Imagine many layers of CO2. At any given instant there are (for illustrative purposes) 8 leaving the ground, 8 bouncing around in the middle, and 8 escaping to space.
Double the CO2. Now there’s a lot more bouncing around to do before escaping to space, so equilibrium is broken. During this time, at any given instant, there are 8 photons leaving the ground, some number greater than 8 bouncing around in the middle, and some number less than 8 escaping. The number bouncing around in the middle will continue to increase until equilibrium is established again.
Once the new equilibrium state has been established, at any given moment in time, there are 8 photons leaving the ground, 16 photons bouncing around in the middle, and 8 photons escaping to space. So the density of photons in the middle does go up, but the number escaping to space once equilibrium is established is exactly the same. But the average height that they escape from is higher.
TimTheToolMan;
Think of it like a lake with a river at one end and a dam at the other. The river flows at 240 m3/2. How much water goes over the dam? Assuming equilibrium and no other factors, 240 m3/2.
Raise the dam by 1 meter. At first it chokes off the flow of water altogether, maybe all the way to zero. How much water is coming in though? 240 m3/s, same as before. What happens to the lake? The level starts to rise. As the level rises, water starts to flow over the dam again. How much does the lake level rise? 1 meter. At which point the amount of water going over the dam is now 240 m3/s, same as before, and same as the amount coming in from the river.
Did the dam create new water? No. Is there more water in the lake than there was before? Yes. But the dam didn’t create it, the dam being raised just held the water back until the depth increased by the same amount as the dam was raised. What is the average height at which the water is escaping from the lake over the dam? 1 meter higher than it used to be. But at no pint did we create “new” water, the only water in the system comes from the river.
AAAAARGH/ m3/s not m3/2
more bourbon…. need more bourbon…
davidmhoffer writes “The GHG’s do not, I repeat DO NOT add additional photons to the system. ”
Of course they do. Photons from the surface are absorbed by the GHGs low down in the atmosphere just above the surface (first 100m or so) and the energy from that photon temporarily held by the GHG is almost always transferred to the rest of the atmosphere (O2 or N2)by collision and heats it.
Thats the “capture radiation from the earth’s surface and warm the atmosphere” part of the process.
Meanwhile the atmosphere as a whole consists of molecules with various amounts of energy each. The distribution of those energies is described by the Maxwell-Boltzmann distribution and at any time a number of molecules have sufficient energy to radiate a photon. Or course many of those molecules are O2 or N2 molecules which cant radiate but a portion of them are GHGs and they do radiate. So if you double the number of GHG molecules then you’re doubling the number of molecules in the atmosphere that can and do radiate both up and down.
Max says: “A Dyson sphere as wide as our orbit around the Sun, at this distance it receives 1366 W/m², and it radiates half of that in and out, so you’ve got a shell of returning photons that started out at 683 W/m² making it back to the surface of the Sun.”
No, the Dyson sphere with a 1 AU radius will absorb 1366 W/m^2 from the sun and emit ~ 1366 W/m^2 outward and ~ 1366 W/m^@ur momisugly inward. Of course, most of the 1366 W/m^@ur momisugly inward will hit some other part of the shell, so the net heat transfer from the shell to the shell is ~ 0.
See “Problem 1026” for more details.
TimTheToolMan;
So if you double the number of GHG molecules then you’re doubling the number of molecules in the atmosphere that can and do radiate both up and down.
>>>>>>>>>>>>>>>>>>
Yup. But what they radiate up and down is the exact same 240 w/m2 as before doubling. So the w/m2 get spread across a greater number of co2 molecules. But there is still only 240 w/m2 coming in and 240 w/m2 going out.
davidmhoffer writes “So the w/m2 get spread across a greater number of co2 molecules.”
In the sense there is no net change, this is true. So if you put more CO2 above a particular altitude then its harder for an individual photon to escape from that altitude. This is the basis for the increased ERL in AGW theory. But if more photons are heading upwards then this must compensate for that increase in opacity.
Remember the original statement for the pro-AGW reference provided by Mosher
““Infrared radiation leaves earth for space from upper troposphere (ERL). Amount increases with temperature at ERL (immediate). Height of ERL is such that total CO2 above it is constant.””
CO2 above is constant? That is a non-intuitive argument as far as I’m concerned even though I can see why many would find it acceptible. with no further thought.