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)
joeldshore says:
April 25, 2013 at 3:19 pm
“Oh yeah…I should perhaps add one more point to my last post: The strict sense in which a colder object cannot heat a warmer object is that the heat (net energy flow) must be from the hot object to the colder object. So, no, adding some cold gas around the Earth and causing the temperature to rise does not mean that the colder gas has heated the Earth: the net flow of energy is still from the Earth to the colder gas. You have just made it harder for energy to leave the Earth, i.e., the Earth has to maintain a higher temperature at its surface in order to radiate away the energy at the rate it is receiving it from the sun……………”
My question;
First your statement: “You have just made it harder for energy to leave the Earth………”
The GHGs are acting like insulators or a blanket then. Correct?
If so, insulation and blankets are solids. they dont expand.
GHGs are gasses that expand, and rise, to absorb the extra heat, and the volume if the atmosphere increases with no increase in temperature. The expanded atmosphere has a greater radiating area to space that handles the extra energy flow.
What is incorrect here? The gasses do not expand? Or what?
TimTheToolMan;
But if more photons are heading upwards then this must compensate for that increase in opacity.
>>>>>>>>>>>>>>
It seems to me that you are thinking of photons purely as particles. For the purposes of illustrating why the ERL increases in altitude, that’s good enough. Going to the deeper levels and details though, they are as much waves as particles, and at that point easier to think of in terms of w/m2 (an energy flux). Neither is ideal, but then photons are not particles or waves either, so no explanation that treats them as one or the other can possibly be completely accurate.
As for Mosher’s original statement, sure, his explanation leaves much to be desired. But him providing a poor explanation doesn’t mean the effect he describes is wrong or that the other explanations you got are incorrect.
Everytime you ask a Greenhouse Gasser for some instrumental readings where the giant infrared light in the sky can be seen, you’re told it’s too secret to measure.
The infrared astronomy field? It’s too hard to measure the giant infrared light in the sky.
The ground based DOWN WELLING RADIATION SENSING FIELD?
They checked your story. For fourteen years.
After fourteen years from the mid ’90s to abou 2010 with hundreds of thousands of readings,
there’s LESS atmospheric infrared down welling at night.
Ask the Greenhouse Gas crowd. Those instruments don’t work right.
Neither does the entire infrared astronomy field. They can’t find the infrared light, so something’s wrong. “They aren’t looking right.”
Al Gore did an experiment online where he put CO2 into a jar beside one with regular atmospheric air. The CO2 jar didn’t get as warm. High Definition photographic artifacts proved he swapped thermometers.
Anthony Watts repeats the experiment online in an unbroken feed. The CO2 filled jar didn’t get as warm. By an amount quite similar to Gore’s.
It doesn’t matter. Just because no instrument can see it, doesn’t mean it’s not there.
The giant infrared light in the sky.
No instruments can find it.
NOAA tried. I told you. They didn’t find any CO2/infrared correlation at night.
http://journals.ametsoc.org/doi/abs/10.1175/2011JCLI4210.1?journalCode=clim
Then there’s the people trying to claim that in spite of the fact that the mathematics for equilibrium show energy migrating from more concentrated to less, that
the math
lies.
On and on and on the stories go. Refrigerators prove thermal energy flows both ways. Go look in a thermodynamics book and it says clearly: refrigerators make use of the fact heat moves from more concentrated to less.
It boils down to the fact that every time you see a Greenhouse Gas person you see
(1) them saying just because the instruments don’t show it, doesn’t mean they don’t show it.
(2)them demanding you put aside the experimental and instrumental evidence showing it’s not as they say, and change the subject to a bright colored picture they put up and demanded you admit, proves it.
(3)them trying to take you with them, down the road of “thermodyamic equations lie when they say energy migrates from more concentrated to less.
Thermodynamic equations, Carnot, Clausius: all that means nothing.
But the fact is that if there were any correlation between infrared light and CO2 we would know.
It’s a giant infrared light.
And we’ve got enough to check for the giant infrared light in the sky a thousand times over.
“No…They believe it because they understand physics.
Look, you can only get so far by comparing the Earth and the moon. The fact that one has a greenhouse effect and the other doesn’t is only one difference. There are other important differences: The moon has very little atmosphere at all and does not have water. This means that the effective heat capacity or “thermal inertia” is much smaller so temperatures vary more dramatically between day and night. Furthermore, the moon has a much longer day than the Earth…about 30 times longer, so this also favors larger temperature variations. Neither of these differences should affect the average temperature (or, more precisely, the average of T^4), which is determined by radiative balance, but they do affect the range of temperatures.”
The greenhouse theory does not consider length of day or heat capacity. Wiki Greenhouse effect:
“If an ideal thermally conductive blackbody was the same distance from the Sun as the Earth is, it would have a temperature of about 5.3 °C. However, since the Earth reflects about 30% of the incoming sunlight, this idealized planet’s effective temperature (the temperature of a blackbody that would emit the same amount of radiation) would be about −18 °C. The surface temperature of this hypothetical planet is 33 °C below Earth’s actual surface temperature of approximately 14 °C. The mechanism that produces this difference between the actual surface temperature and the effective temperature is due to the atmosphere and is known as the greenhouse effect.”
https://en.wikipedia.org/wiki/Greenhouse_effect
So idea that ideal blackbody could be in a vacuum or not is not relevant, and the general assumption would be that things in space are in a vacuum and this ideal blackbody is in a vacuum. So in model it’s in a vacuum and whether it’s rotating or spinning on two axis is not considered a factor.
Or there is no modifier for having to do with whether a planet has thick atmosphere or a vacuum,
and whether planet has a lot of water or no water.
The only modifier is distance to Sun and how much the body reflects. If body doesn’t reflect sunlight or is a black body like the Moon it is suppose to have a average temperature at Earth distance from the sun of 5.3 °C. Since the Moon is slightly reflective, it’s average temperature
should be around 5 C. And if the Moon was reflective as Earth, then it’s average temperature should according to this theory be −18 °C..
If the Moon was an reflective as Earth and Moon had same average temperature a earth [about 14 C] then the only reason it could 33 C warmer then “it should be” is because it must have a greenhouse effect.
As this is according to Greenhouse theory the only way it can be warmer. So theory does not allow for a body to be warmer because it has faster rotation or because it has water [unless water is vapor form which makes a “greenhouse gas”].
As I said you don’t even follow [or know] the theory you purport to support.
“For heaven’s sake, think things through before making statements about people being brainwashed. You might find that you can actually learn from people who have thought about these things much more than you apparently have.”
Hmm. I am curious, do you think the people in North Korea have been and are being brainwashed. Also do you think the German people were brainwashed by the Nazi government?
Would know what brainwashing was if you saw it?
brain·wash·ing
“[breyn-wosh-ing, -waw-shing] Show IPA
noun
1.
a method for systematically changing attitudes or altering beliefs, originated in totalitarian countries, especially through the use of torture, drugs, or psychological-stress techniques.
2.
any method of controlled systematic indoctrination, especially one based on repetition or confusion: brainwashing by TV commercials.
3.
an instance of subjecting or being subjected to such techniques: efforts to halt the brainwashing of captive audiences.”
http://dictionary.reference.com/browse/brainwashing
So are willing to admit that TV commercials a form of brainwashing- even if they are funny and amusing?
And do you know what social conditioning is?
Wiki:
“Social conditioning refers to the sociological process of training individuals in a society to respond in a manner generally approved by the society in general and peer groups within society. The concept is stronger than that of socialization, which refers to the process of inheriting norms, customs and ideologies. Manifestations of social conditioning are vast, but they are generally categorized as social patterns and social structures including education, employment, entertainment, popular culture, religion, spirituality and family life. The social structure in which an individual finds him or herself influences and can determine their social actions and responses.
Social conditioning represents the environment and personal experience in the nature vs. nurture debate. Society in general and peer groups within society set the norms which shape the behavior of actors within the social system.”
Social conditioning or brainwashing is what Al Gore and others who “lie for the sake of the cause” are trying to do- this is the only point of saying such things as the “science is settled”.
This the only point of suggesting people should imprisoned or executed because they don’t believing in global warming [or are unwilling to do enough to stop it].
Get it?
“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. ”
Are you sure you mean it that way TimF? Seems you have 1366 input and 1366 x 2 output.
Gary Hladik says, April 25, 2013 at 3:59 pm:
“Kristian says (April 25, 2013 at 3:11 pm): “You’re still not reading what you’re commenting on, Gary.”
Oh, but I did. I read very carefully, multiple times, because I couldn’t actually believe I was reading what I thought I was reading. Here, your words:
“The ‘system’ flux to the surroundings is J with sphere alone and J1 (J/2) with shell surrounding it. How can this be?”
Indeed! How can this be unless 1) you’re destroying energy, or 2) the system isn’t in equilibrium? What do you think I’m missing here? Specifically.“
Sigh.
No, evidently your reading is not very ‘careful’, Gary. Careful in your ‘misunderstanding’ of what you’re reading, yes. But not in actually taking in the meaning of the words in front of you. Because the answer is right there for all to see in the very posts you’re commenting on. So your misrepresentation of them seems to me to be simply an exercise in building strawmen to take down.
As a matter of fact, for your comment on April 25, 2013 at 2:26 pm, you need only read on, just past your quote of choice, to see it. In your comment on April 25, 2013 at 3:03 pm, it’s even in the very paragraph you’re quoting (and, rephrased, in the one directly following it, which you are not).
Bill from Nevada;
Everytime you ask a Greenhouse Gasser for some instrumental readings where the giant infrared light in the sky can be seen, you’re told it’s too secret to measure.
>>>>>>>>>>>>>>>>>>>>>>>
Oh bull.
http://wattsupwiththat.com/2011/03/10/visualizing-the-greenhouse-effect-emission-spectra/
scroll down and you will find the exact instrumental readings you claim don’t exist.
Or you can go here for ERBE data showing satellite data of the same:
http://eos.atmos.washington.edu/erbe/
The hardest part about gaining any new idea is sweeping out the false idea occupying that niche. As long as that niche is occupied, evidence and proof and logical demonstration get nowhere.
~ Robert A Heinlein
TimTheToolMan says:
April 25, 2013 at 8:51 pm
——————————————–
Tim,
It should be obvious from responses to your comments that you have struck a nerve. You are essentially correct. The energy that radiative gases are radiating to space includes not just intercepted surface IR, but energy from surface conduction and release of latent heat. The atmospheric cooling effect is an almost linear function of CO2 concentration in the atmosphere, whereas the warming effect is an inverse logarithmic function of CO2 concentration.
For a hypothetical static atmosphere this would mean that initially CO2 would warm but after a certain CO2 concentration (point of no concern) the two curves would cross and the net radiative effect of added CO2 would be cooling. However for a moving atmosphere this does not hold true. For an atmosphere in which the gases can move, CO2 cools at all concentrations above 0.0ppm.
The reason the defenders of the AGW faith are fighting so hard to keep the ERL game alive is not to save the AGW hypothesis. They know the jig is up. The mistake at the foundation of the AGW hypothesis is in the basic physics of gas conduction and convective circulation. So basic it is embarrassing. At this time they are looking for a less embarrassing exit that sounds suitably “sciency”. Sadly they are being assisted in their exit plans by equally embarrassed Lukewarmers who endorsed the mistakes.
If you want evidence that you are on the right track, look no further than Steve Moshers early comment on this thread –
“The real debate is over how much warming GHGs will cause”
The defenders of the AGW faith want the exit answer to be “CO2 causes warming but we overestimated how much.” The truth is that radiative gases act to cool our atmosphere at all concentrations above 0.0ppm.
There are no planets or moons in our solar system that have managed to retain an atmosphere without radiative gases. They are that important to atmospheric cooling.
“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.” ~Tim
Uh… as wayne pointed out, that’s 1366*2 from the sphere, isn’t it?
Hoffer you do well to quote science fiction authors.
“These plots are annual and seasonal means of data obtained from the NASA Earth Radiation Budget Experiment (ERBE) scanner instruments onboard the ERBS and NOAA-9 satellites during January 1985 through December 1986.”
I and anyone else who was really serious about this would be talking about you can replicate – showing a correlation between CO2 and atmospheric infrared, in the earth-radiant frequency.
Or CO2 and global temperatures.
Nothing reinforcing your claim that there’s CO2 associated thermal behavior, OR atmospheric infrared in attributable is there in your spam.
Hoffer you’re the one I saw making the claim that refrigeration is based on the laws of thermodynamics allowing heat to flow two ways, I believe.
You’re also the one I know
I saw say that when the thermodynamic equations are done proving heat travels one way, there is actually energy flowing both ways, but that mathematics can’t show that.
F for grabbing graphs that mean nothing,
F for bloviating about it THEN grabbing graphs that mean nothing.
And F for thinking the math of thermodynamics is lying when it tells you heat travels one way to equilibrium.
So I missed joeldshore’s post which amongst other things said this “The amount of energy that a substance emits is determined by its temperature.”
That is the crux of his argument and is correct. The amount of radiative energy radiated by an object is given by S-B and does indeed relate only to temperature. However the number of molecules that will be radiating is determined not by the temperature alone but by their concentration according to Maxwell-Boltzmann. And it is this that joeldshore is missing in his argument.
Hoffer :
when you told someone the math of thermodynamics lie
when they say *heat flow is one way*
you entered into that special realm called “No, I don’t have any credentials but I do a lot of blogging, pretending to be an expert on the internet.”
I’ve seen you try MULTIPLE TIMES, telling people refrigerators are built on the principle that heat flows simultaneously two directions between two entities.
I saw you say it on the RW Wood thread.
But the fact is, thermodynamics texts point out the refrigerator as a proof of energy flowing ONE way.
In response to joeldshore I wrote “The amount of radiative energy radiated by an object is given by S-B and does indeed relate only to temperature. ”
But was too quick to agree with joeldshore. Normally the amount of energy radiated varies “only” with temperature but according to Stefan-Boltzmann it actually varies with the product of temperature and emissivity. In the case of adding GHGs to the atmosphere, the emissivity is actually increasing so we can expect more radiation to propagate throughout the atmosphere (up and down for no net effect).
I should have realised earlier but it has to be this way for the result to be in line with the requirements of Maxwell-Boltzmann’s distribution of energies…
davidmhoffer says:
April 25, 2013 at 8:08 pm
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.
Your: “ALL the photons are from the ground in the first place.”
Only in the make believe world of AGWScienceFiction fisics.
In the real world we get real heat photons from the Sun – this is what we feel as heat,
this is the electromagnetic radiation wave of thermal infrared, also known as HEAT, also known as thermal infrared also known as heat radiation also known as radiant heat also known as longwave infrared.
AGWSF has completely excised that direct longwave infrared from the Sun in order to claim that the only “downwelling longwave infrared from the atmosphere is from backradiation by greenhouse gases”. This is science deliberately faked.
AGWSF has given the properties and processes of longwave infrared from the Sun to the shortwaves classified in traditional physics as Light not heat – mainly visible, a small amount of uv and 1% near infrared. The latter two hardly mentioned so the AGWSF claim is that Visible light from the Sun heats the Earth’s land and water – this is patently absurd to anyone with real world basic physics..
Visible light interacts with matter on the electronic transition level, this is not capable of moving whole molecules into vibration which is what it takes to heat matter.
Visible light from the Sun can’t even get to the electrons of water, water transmits visible light unchanged.
Visible light is bounced all over the sky by the electrons of the molecules of nitrogen and oxygen which absorb visible light and then emit it, this is called reflection/scattering and is how we get our blue sky.
If visible light is such a powerful energy as the AGWSF claims that it heats matter on being absorbed, how much is blue visible light from the Sun heating the atmosphere as the electrons of the gas air absorb it?
As if that wasn’t absurd enough, AGWScienceFiction gives two reasons why there is no direct thermal energy in transfer from the Sun, which is longwave infrared also known as thermal infrared to differentiate between the heat it is and the non thermal shortwave infrared which are classed in with Light, not with Heat; classed in with Reflective, not Thermal.
We cannot feel Light as Heat.
The heat we feel from direct from the Sun is thermal infrared, longwave infrared. AGWSF claims we get no direct heat from the Sun and explains this firstly by claiming “there is an invisible barrier at TOA like the glass of a greenhouse which stops longwave infrared from the Sun but allows visible from the Sun to get through and heat the Earth’s surface”.
What is this invisible barrier around the Earth stopping the Sun’s direct heat, longwave infrared, from reaching us? It is unknown in traditional real word physics.
The second even more absurd explanation given by AGWSF for why they claim “no longwave infrared from the Sun reaches us”, is by saying “the Sun produces insignificant amounts of longwave infrared and so there is nothing of this to reach us”.
The heat we feel from the Sun is longwave infrared. We cannot feel visible light, we cannot feel the shortwaves of visible, uv and near infrared which AGW claim is heat energy. We cannot physically feel these shortwaves as heat.
AGWSF is actually in real world physics saying there is no heat direct from the Sun.
The explanation they give for why “the Sun produces no significant longwave infrared” is that “the peak energy from the Sun is visible and that makes the Sun 6000°C, so no significant longwave infrared which is the electromagnetic wave of heat energy is produced, it’s all changed to mainly visible”.
Those mindlessly regurgitating this AGWSF meme of “shortwave in longwave out” can’t see how ludicrous that explanation. How ludicrous that a three hundred mile band of visible light, the first layer of atmosphere around the Sun, defines the temperature of Sun, which is millions°C and continually radiating out this heat.
The hotter something is the more heat it radiates, like the incandescant lightbulb which radiates 95% heat, longwave infrared, and only 5% visible light. The 300 mile wide band of visible light around the Sun is as insignificant as it is in the lightbulb. The Sun is a massive blazing STAR! It is radiating massive amounts of HEAT!
Heat is Longwave infrared.
This sleight of hand trickery has been put into place by AGWSF in order to push AGW, it has had the effect of dumbing down basic real world physics for the majority population.
Because the AGWSF meme that “visible light from the Sun heats the Earth’s surface” has been brainwashed through the general education system so the majority population without traditional physics thinks Light is Heat, is why you think that the only source of heat downwelling in the atmosphere comes from the heated Earth radiating out, from the upwelling of waste heat being “backradiated”.
NASA used to teach traditional physics that the heat we feel from the Sun is longwave infrared and that we cannot feel shortwave infrared, which is not hot, is not thermal.
You cannot ignore the following, you must address this because it completely contradicts your AGWSF Greenhouse Effect Energy Budget.
NASA used to teach:
“Far infrared waves are thermal. In other words, we experience this type of infrared radiation every day in the form of heat! The heat that we feel from sunlight, a fire, a radiator or a warm sidewalk is infrared.
“Shorter, near infrared waves are not hot at all – in fact you cannot even feel them. These shorter wavelengths are the ones used by your TV’s remote control.”
You live in a cold world – with no direct longwave infrared from the Sun which is radiant heat which is the Sun’s thermal energy in tranfer, and your visible light from the Sun cannot raise the temperature of matter.
Deal with it.
“Climate pseudo scientists are rubbish at fluid dynamics.”
Heat Transfer too. They would fail a basic engineering exam (multimodal heat transfer). Logic is not their strong side as well.
Bill,
If you think the maths of thermodynamics says heat flows only one way, how do you suppose the body sending the heat know the temperature of the receiving body to decide when to send it? That would appear to require faster-than-light propagation.
So far as I know, refrigerators are based on the same thermodynamics as any heat transfer, they’re principally used as an example to show that heat engines are reversible. A heat engine transfers heat from warm to cold, doing work on its surroundings. A refrigerator transfers heat from cold to warm as a result of the surroundings doing work on it. It’s a demonstration that heat can go both ways, but not explicitly a demonstration that it does so simultaneously (although it does).
That thermodynamic heat flow is the net effect of bidirectional heat flows is shown by equilibrium behaviour combined with the requirement for the laws of physics to be local – with action-at-a-distance banned. Locality requires that events at a point can only be caused by conditions at that point. The transfer of heat between one point and another takes time. So the decision to send it can only depend on conditions at the sender location. For it to decide how much to send depending on the temperature difference would require that it somehow know what the temperature is at the receiver location. But if the receiver location is not emitting any heat in its direction, there must be some other means of signalling what the remote temperature is. What is it?
And what evidence is there for it, when simply having all objects emit heat according to their own local temperature, and for the heat emitted to rise as the temperature does, gives exactly the observed result?
Max™ says (April 25, 2013 at 11:12 pm): “<i“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.” ~Tim
Uh… as wayne pointed out, that’s 1366*2 from the sphere, isn’t it?”
tjfolkerts is correct. I plugged these numbers into problem 1026:
R = 1 AU ~ 1.5 x 10^11 m)
r ~ 7 x 10^8 m
T = 5778 K
T0 = 0 K
and solved for T1, the temperature of the shell. The answer is ~394 K. I entered that into an online Stefan-Boltzmann calculator and got ~1366 watts per square meter. Since the shell has two sides, it radiates 1366 watts per square meter from each side of the shell.
Intuitively this makes sense: at 1 AU the sun subtends an angle of only about 0.5 degrees, so a vastly greater proportion of the shell’s “IN” radiation misses the sun and hits…the shell again. The shell is, in effect, getting a “double dose” of the sun’s radiation, part from the sun, and part from itself.
In problem 1023, R is very close to r, so the shell only “sees” the sphere and not itself. The shell’s inner radiation heats the inner sphere and not itself, at least not directly.
Max™ says (April 25, 2013 at 7:18 pm): “Why do you think the sun wouldn’t absorb the incoming energy?
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…”
Not “noticeable” on such a hot object, but not zero, either.
“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.”
The surface matter of the sun is heated by conduction, convection, and radiation from the interior of the sun. So why would the surface matter of the sun not interact with and be heated by radiation from outside the sun?
As tjfolkerts has pointed out, a shell at 1 AU won’t send much radiation to the sun, so if it helps, put the shell closer, as in problem 1023. Now we’re getting roughly half the sun’s output back. Significant, right? Now move the shell outward incrementally. At what distance does the sun start “rejecting” incoming radiation?
BTW, of course we’re ignoring any effects such an imaginary shell would have on solar magnetic fields, flares, etc.
Kristian says (April 25, 2013 at 9:54 pm): “As a matter of fact, for your comment on April 25, 2013 at 2:26 pm, you need only read on, just past your quote of choice, to see it. In your comment on April 25, 2013 at 3:03 pm, it’s even in the very paragraph you’re quoting (and, rephrased, in the one directly following it, which you are not).”
I did read all of that, and it still doesn’t change the fact that, supposedly at equilbrium, power J is input to the system and power J1 = J/2 is radiating out. Either the temperature of the system rises (in which case it wasn’t at equilibrium), or energy is being destroyed. If the system is at equilibrium, you have to explain where the “extra” power J1 = J/2 is going. Note that if the input power is actually J1, inputs and outputs balance nicely and the system is indeed at equilibrium.
BTW, rather than telling me to read on to find “it”, why not just repeat “it”? That makes it a lot easier to figure out what you’re trying to say.
Reed Coray:
I am replying to your post addressed to me at April 25, 2013 at 5:18 pm
http://wattsupwiththat.com/2013/04/24/spencer-slays-with-sarcasm/#comment-1287852
You post concludes saying
That changes the subject.
I attempted to resolve a confusion and you say that is now achieved. This pleases me.
In fact, I think you can answer all the questions you pose for yourself.
1.
Consider that atmospheric water vapour was not a greenhouse gas (GHG) and none of the atmospheric trace gases were (GHGs). Then the albedo of the Earth would be unchanged and the total heat input (from the Sun) to the Earth+atmosphere system would be unchanged. And all of that heat would be provided to the Earth’s surface. All that energy would radiate from the surface to space unhindered by GHGs.
[Radiation from Earth surface –> space]
2.
In reality, water vapour and some of the trace gases in the air are (GHGs). A little of the mostly short-wave radiation from the Sun is absorbed in the atmosphere by GHGs. But GHGs only absorb a little of this short-wave radiation. Importantly, the total heat input (from the Sun) to the Earth+atmosphere system is the same as in Case 1. Most of the radiation from the Earth’s surface is long-wave radiation which is efficiently absorbed in the atmosphere by GHGs. This inhibits the passage of radiation from the Earth’s surface to space so the temperature of the Earth’s surface rises (for the same reason that an insulated house is warmer than an uninsulated house).
[Radiation from Earth surface –> atmosphere (i.e. effectively insulation) –> space]
I really do think you now have sufficient basic information to think this through for yourself. And answering the questions you have posed yourself will be more cogent for you than being ‘told’ their answers by anybody.
Please be assured that I have tried to help.
Richard
Nullius in Verba says, April 26, 2013 at 1:43 am:
“If you think the maths of thermodynamics says heat flows only one way, how do you suppose the body sending the heat know the temperature of the receiving body to decide when to send it? That would appear to require faster-than-light propagation.”
“That thermodynamic heat flow is the net effect of bidirectional heat flows is shown by equilibrium behaviour combined with the requirement for the laws of physics to be local – with action-at-a-distance banned.”
“And what evidence is there for it, when simply having all objects emit heat according to their own local temperature, and for the heat emitted to rise as the temperature does, gives exactly the observed result?”
Yes, this seems very much to be where the confusion arises. SoD’s confusion, for instance, about what the second law of thermodynamics is actually saying and not saying.
Heat is always energy. Energy is NOT necessarily always heat. There is a very specific physical definition of ‘heat’ and it has been proposed and conceptually refined over the years in order to distinguish between energy flows that can and cannot warm an object. Only energy in the form of heat can make an object warmer. Here is HEAT defined by Borgnakke & Sonntag (‘Fundamentals of Thermodynamics,’ 2009):
“If a block of hot copper is placed in a beaker of cold water, we know from experience that the block of copper cools down and the water warms up until the copper and water reach the same temperature. What causes this decrease in the temperature of the copper and the increase in the temperature of the water? We say that it is the result of the transfer of energy from the copper block to the water. It is from such a transfer of energy that we arrive at a definition of heat.
Heat is defined as the form of energy that is transferred across the boundary of a system at a given temperature to another system (or the surroundings) at a lower temperature by virtue of the temperature difference between the two systems. That is, heat is transferred from the system at the higher temperature to the system at the lower temperature, and the heat transfer occurs solely because of the temperature difference between the two systems.”
“Heat, like work, is a form of energy transfer to or from a system.“
The last line relates heat and work and thus relates the sphere/shell problem to the Carnot cycle. Q = Q’ + Q” is the equivalent to W = Qh – Qc:
http://i1172.photobucket.com/albums/r565/Keyell/Carnot_zps4049e783.jpg
Combine this with what Wikipedia says:
“Heat in physics is defined as energy transferred by thermal interactions. Heat flows spontaneously from hotter to colder systems. When two systems come into thermal contact, they exchange energy through the microscopic interactions of their particles. When the systems are at different temperatures, the result is a spontaneous net flow of energy that continues until the temperatures are equal. At that point the net flow of energy is zero, and the systems are said to be in thermal equilibrium. Spontaneous heat transfer is an irreversible process.”
“When energy is transferred to a body purely as heat, its internal energy increases. This additional energy is stored as kinetic and potential energy of the atoms and molecules in the body. Heat itself is not stored within a body. Like work, it exists only as energy in transit from one body to another or between a body and its surroundings.“
There is no net heat flow. There is only net energy flow. The net energy flow is the heat flow. Heat is specifically the surplus energy transferred from a warmer body to a cooler one. There is no ‘heat’ going the other way. There is ‘energy’ going the other way, but this can do nothing to make the warmer object warmer still. Only heat can heat.
There is also a fairly interesting distinction between ‘thermal energy’ and ‘heat’:
http://en.wikipedia.org/wiki/Thermal_energy
Roy Spencer says:
April 24, 2013 at 1:37 pm
ALL:
It is important to remember that there is NO WAY to determine the temperature of anything based upon the rate of energy input alone, for example the Earth absorbing an average of ~240 W/m2 from the Sun. Temperature is a function of BOTH energy input (typically not temperature dependent) AND energy loss (typically VERY temperature dependent), neglecting issues related to heat capacity which mainly affect the time required for the system to equilibrate. The temperature of anything heated will increase until the rate of energy *loss* equals the rate of energy *gain*. So, temperature can be increased by increasing INPUT, or decreasing OUTPUT.
=======================================================\
Well Dr Spencer, you could have just qu0ted David’s Law…
“At its most basic only two things can effect the energy content of any system in a radiative balance. Either a change in the input, or a change in the “residence time” of some aspect of those energies within the system.”
It therefore possibly follows that any effect which increases the residence time of LW energy in the atmosphere, (for instance; green house gases) but reduces the input of SW energy entering the oceans, (atmospheric heating causing more W/V and or cloud cover) causes a net reduction in the earth’s energy balance, proportioned to the energy change involved, relative to the residence time of the radiations involved.
Kristian says: “Only energy in the form of heat can make an object warmer.”
Rubbing your hands together is work, not heat.
Running electric current through a resistor is work, not heat.
Compressing a piston is work, not heat.
All of these clearly make an object warmer.
Kristian,
Yes, that’s a technical distinction some people choose to make, and it is confusing. I’m not sure whether it is more confusing to use the technical sense or the everyday sense. Which conveys understanding better to people who don’t know the physics?
It depends as well where you draw the boundaries. Objects can have non-uniform temperature.
If you want to use the technical definition, then you can make a warm object warmer without transferring any heat. Adiabatic changes are those with no heat transfer, but warm objects can get warmer as a result of them. You can argue that only heat can heat, but then heating does not mean the same thing as raising the temperature. Heating is not warming.
That seems to me even more likely to confuse.
TimTheToolMan says:
What you are missing is that emissivity is proportional to absorptivity (and both depend on the thickness of the gas layer). When it emits more, it also absorbs more. At the end of the day, what changes as you change the concentration of GHGs is where the emission occurs…and that, through the temperature, determines how much is emitted.
Let’s consider the case of a solid rather than a gas. Now, if you make this solid twice as thick, do you think you get twice the radiative emission because you have twice the number of emitting molecules? No, you get the same because the amount depends on the surface area. Now imagine the entire atmosphere is solid and that it somehow still has the same temperature gradient (say 8 K per kilometer to keep the math simple) that we observe with the lapse rate, with a temperature of 288 K at the bottom. If this solid atmosphere were initially 5 km high, then the emission would occur from an upper surface that is at 248 K. If it then became 1 km thicker, so it extended up to 6 km high, its upper surface would be at 240 K and it would emit less energy to space.
I know this is all somewhat counterintuitive but the fact that you don’t understand what is going on is not going to change the reality of what happens: http://www.barrettbellamyclimate.com/userimages/Iraq2.jpg and the fact that entire fields of technology are based on atmospheric radiation transfer working the way that we say it does.