Life is too short
Life is too short to occupy oneself with the slaying of the slain more than once. - TH Huxley (ear tip to Simon Donner for the quote)
Then again, that assumes Eli has a life, so once, more, dear bunnies we confront Zombie George Chilingar and the Adiabat of Death. The playing field is well described by Joel Stein
Everyone else in my family — my dad, my sister, my mom — loves to argue with idiots.Well, not multiplication in Chilingar, Khyuk and Sorokhin's case, but gravity which is pretty much multiplication for physicists, a bit more complex than addition, but basic. The summer is over, the little rabetts are preparing for the beginning of school (they better be). On to Energy Sources Part A 30 (2008) 1-9 published January 1 2008 by G.V. Chilingar, L.F. Khilyuk and O.G. Sorokhtin entitled "Cooling of Atmosphere Due to CO2 Emission" and a bit earlier in Environmental Geology. Kind of like New York, New York is the city with the same name twice, C&Co publish the same paper twice, at least.
When my mom, a therapist, visited me in Los Angeles in the spring, she saw the “Psychiatry Kills!” sign on Sunset Boulevard outside the Citizens Commission on Human Rights. Even after I told her, for the 10th time, that the organization was part of the Church of Scientology, she still wanted to stop by and “have a conversation with these people.” I have no doubt that my toilet training included a lot of unnecessary back and forth.
Me, I’d rather smile and nod and save my energy. Let George Bush try to convince jihadists how awesome the Bill of Rights is. My theory is that when you see a guy walking your way waving a knife and talking to himself, you switch sides of the street, not engage him in a civics lesson. But that’s just me.
So when I found out that Eugenie Scott, a former anthropology professor and president of the American Association of Physical Anthropologists, has spent the last 19 years promoting evolution as head of the National Center for Science Education, I knew I had to find her and make fun of her. This is a woman who is spending her life informing people about scientific discoveries made 147 years ago and who wrote a whole book called Evolution vs. Creationism: An Introduction. “Sisyphus with a smile” is how Scientific American described her. It’s as if she spends her time trying to convince people that multiplication totally works.
The Rabett has taken part in a discussion of this paper on the Climate Audit Bulletin Board. C & Co blather a bit about how smart they are, how there are all these wonderful results, mostly from Sorokhin in the the iconic Russian literature, but it all comes back to an adiabatic expansion, and the relationship that can be derived from it between temperature and pressure
(1) T = Cpα
where C is a constant, α = (γ -1)/γ being the ratio between the specific heat at constant pressure and that at constant volume, cp/cv. Since cp-cv = R, the gas constant, 8.314 J/mol-K, α = R/cp. They get all proud of themselves for a trivial rearrangement, taking ratios of T and p at the surface and in the atmosphere to get
(2) T = bα Te ( p/po) α
With Te and po being the temperature and pressure at the surface. At this point, C&Co have reduced everything to determining α and thus cp. They separate cp in to three terms, the specific heat of the gases in the atmosphere and two additional undetermined terms which they associate with radiation and water vapor. They do not separate the sensible and latent heats of water. By comparing the temperature profile of the atmosphere with (2) they obtain a fit to α from which they impute the values of the other two heat capacities by difference. The two additional terms are found to be small compared to the gas heat capacities (essentially 7/2 R). Thus they claim that convection determines the temperature in the atmosphere.
There is lots of silly there. For one, you can't ignore greenhouse gases absorbing radiation from the ground, and radiating a fair bit of it back. If you do, you find that that solar heating alone cannot keep the surface at a toasty 288 K. C&Co's only admit to processes which REMOVE energy from the surface, so the surface will cool drastically, way below the case where there is no atmosphere and no convection, because in the chilingarsphere, convection et al, only REMOVE heat from the surface
Eq 2 is the case for what happens in a small system, or out in space, and it is easy to derive from the first law of thermodynamics. But the first law (physicists version where work is done on the surroundings)
(3) dU = δQ - δW
where U is internal energy (all the energy of the atmosphere), Q is heat flowing into and out of the system and W the work done by the system. In the atmosphere we need another term, the potential energy associated with gravity
(4) dU+ mg dz = δQ - δW
where z is the altitude of the packet of air we are looking at m the mass and g the acceleration of gravity. (UPDATE: The term on the left is the total energy of any infinitesmally small packet of air. The first term dU is essentially the kinetic energy of the molecules in the packet, the second their gravitational potential energy. One can, in principal, trade one off for the other. If the total energy stays the same ( δQ - δW=0) if z becomes smaller, that corresponds to the packet being pushed down, then the kinetic energy, and thus the temperature will increase and visa versa.)
Let us warm up (or better said, cool down) with a quick derivation of how gravity enters the picture through the adiabatic lapse rate, the rate at which the air would cool with altitude if there were no water vapor condensation, greenhouse gas radiation and other things (BTW, George C don't think, those things are very important either).
Atmoz, is a great fan of Met 101. Keeping with first things first, we have to have the equations of hydrostatic equilibrium the derivations are at the link
(5) dp/p =( μ g/RT) dz
where p is the pressure on a packet of air, dp the pressure difference between the top and bottom of the packet, μ the average molar mass of air, R is the gas constant and T the temperature of the packet. In an isothermal atmosphere
(6) p = po exp (-z/zo)
po is the pressure at ground level and zo= (RT/μ g) is called the isothermal scale height (about 8 km for the earth). For an adiabatic expansion temperature changes with altitude as
(7) dT/dz = [(γ -1)/γ] (μ g/R)
For the Earth's atmosphere, C dT/dz is the dry adiabatic lapse rate, about 8 K/km for the Earth. Eq 6 does a good job of predicting the temperature as a function of altitude for dry regions (the poles, deserts, etc), however, it fails to consider water vapor which heats the atmosphere by contributing the sensible and latent heats, thus the dry.
Chilingar, Khyuk and Sorokhin do not include the effect of the dry adiabatic lapse rate (gravity) in their model. This leads them incorrectly to assigns the entire pressure difference resulting from the dry adiabatic lapse rate to convection. This is incorrect, wrong, mistaken, erroneous, untrue, inaccurate, false, faulty, improper, flawed, inappropriate, unseemly, unbecoming, offensive, indecent, and just plain off.
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48 comments:
> Eq 6 does a good job
Seems like Eq. 7 to me.
BTW I am not quite sure you got your fingers on the most outrageous wrongness. To me it seems that what they do is differentiating your Eq. (1),
(1) T = C * p^alpha,
in order to arrive at (for p = p0 = 1 atm)
Delta-T = T * alpha * Delta-p,
and then (of course) Delta-p due to adding CO2 is verry verry small :-)
They forget that there is a constant C in Eq. (1), and no, once you start tinkering with CO2 it's no longer a constant...
:wq
The level of wrongness to which they've sunk is ... astounding. Dumbfounding. Almost incomprehensible.
It's a sad commentary on the human race that such drivel actually gets credence from anyone; the level of ignorance it takes to believe it is ... astounding. Dumbfounding. Almost incomprehensible.
But I'm sure there's at least one U.S. senator -- from Oklahoma -- who believes it.
It's pretty sad.
These guys can't even get the pressure increase for CO2 doubling right.
Here's what they say:
If, for example, the concentration of carbon dioxide in the atmosphere increases two times (from 0.035% to 0.07%), which is expected by the year of 2100, then the atmospheric pressure will increase by Δp ≈ 1.48x10-4 atm (Sorokhtin, 2001).
Actually, the CO2 mixing ratio in 2001 was closer to 370ppm than to 350ppm and the doubling of CO2 by 2100 is usually referenced to a mixing ratio of about 280ppm (at the beginning of the industrial revolution).
Most scientists do not have CO2 going to 700ppm by 2100. In order for that to happen, it would have to go up (on average) by 3.4ppm per year, or by > 1.5 times the current yearly increase (2ppm)
But there is actually a bigger problem (damned incestuous references)
if the concentration of carbon dioxide in the atmosphere increases from 0.035% to 0.07%, that means the mole fraction of CO2 increases by .00035, which means the CO2 partial pressure goes up by the same amount (measured in atm)
IE, it goes up by 3.5 x10-4 atm, not by 1.48x10-4 atm
Of course, their main problem is that they simply ignore CO2's greenhouse property, which, you gotta admit, does simplify the calculations considerably!
Unfortunately, as Einstein said, one should make things simple, but not too simple.
Tamino
I think the problem is twofold:
1) many people have learned to "question" the scientific concenus without ever learning how to question.
They seem to believe that being skeptical involves nothing more than simply questioning/challenging the experts -- in this case the vast majority of climate scientists.
2) when most of these people see an equation, their eyes glaze over. They have no idea how to determine what it means -- or if it even means anything at all.
If the expert has an equation and the challenger also has an equation, they side with the "challenger" because they have no clue how to decide which is right, and, all else being equal, the challenger gets the benefit of the doubt because (as everyone knows) he/she is the "skeptical" one.
The underlying problem is that everyone thinks they're qualified to comment on the weather/climate because it's easy to go outside and tell if its warm or cold. Or if it's raining, etc. I have seen very few lay people attempt to overthrow the consensus on, say, quantum electrodynamics.
Is it because climate science has political implications while QED doesn't? Yes and no. It will almost certainly require political intervention to stem the use of the atmosphere as a dumping ground for CO2. But problems in physics have political implications as well. It costs a lot of money to physics research. I'm sure about half the people of the US think it's a waste of money. But where is the public outrage as in the case of climate science?
More importantly, it's that people are afraid that any oversight or regulation of "The Free Market" (TFM) will inevitably lead to worldwide communism. A lot of people want to make as much money as possible, and they don't care how many people they screw along the way. Any oversight or regulations that limit the screwing results in them not making as much money.
And I don't buy the argument that regulating CO2 emissions will cause an undue strain on the economy. Consider CFCs. During their height, DuPont made 25% of them, but it only accounted for 2% of their business. Yet after they stopped making them, their stock price rose by ~200% over then next few years. [NYTimes, 1988, stock price via Google Finance] All that hubbub about it causing undue stress on them financially seems to have been a smokescreen.
I have seen very few lay people attempt to overthrow the consensus on, say, quantum electrodynamics.
That may be partly because most people (even some scientists who never took advanced physics) have never even heard of it (and most people would have no clue what "QED" means, even its traditional use) Good thing, too because if they knew what QED was all about, they would certainly think it was a commie plot, what with all those ideas about all electrons being exactly alike and so forth.
but there are quite a few laymen (maybe even a few lay-women, too, but mainly men, I'd guess) who regularly attempt to "debunk" Einstein's Special Relativity.
There is an element of "Einstein was not so smart. Even I can see what he did wrong."
They don't do it with General Relativity as often because, I suspect, the math is just a little too daunting (evewn for most scientists!) Too many subscripts and superscripts and greek letters.
Special relativity, on the other hand is just basic algebra, which most people are familiar enough with to get into trouble (kinda like the birds and the bees)
However, I do agree that climate science is an extreme when it comes to everyone thinking they're an expert, though.
And the point about free market libertarianism certainly has a lot of truth to it.
if they knew what QED was all about, they would certainly think it was a commie plot, what with all those ideas about all electrons being exactly alike
But they aren't... similar perhaps, but not alike. Now if you'd said photons...
It's a bit surprising that quantum hasn't attracted the fundamentalists. They would freak out if they really understood it... like happened to Einstein. And he wasn't even a fundamentalist.
Ah, but all electrons are exactly alike
They can have different momenta, energy,etc, but fundamentally, they are the same.
Some things in Nature are exactly alike. For example, our understanding of elementary particles indicates that all electrons are exactly, precisely the same. This is one of the cornerstones of quantum physics, and if you think for a bit you will see that this is a profound statement. Electrons are true elementary particles, in that they have no component parts; thus they are all exactly alike.
In fact, John Wheeler once suggested that that all electrons might actually be the same particle!
From Feynman's Nobel lecture
http://www.nobel.se/physics/laureates/1965/feynman-lecture.html
"As a by-product of this same view, I received a telephone call one day at the graduate college at Princeton from Professor Wheeler, in which he said, "Feynman, I know why all electrons have the same charge and the same mass" "Why?" "Because, they are all the same electron!" And, then he explained on the telephone, "suppose that the world lines which we were ordinarily considering before in time and space - instead of only going up in time were a tremendous knot, and then, when we cut through the knot, by the plane corresponding to a fixed time, we would see many, many world lines and that would represent many electrons, except for one thing. If in one section this is an ordinary electron world line, in the section in which it reversed itself and is coming back from the future we have the wrong sign to the proper time - to the proper four velocities - and that's equivalent to changing the sign of the charge, and, therefore, that part of a path would act like a positron." "But, Professor", I said, "there aren't as many positrons as electrons." "Well, maybe they are hidden in the protons or something", he said. I did not take the idea that all the electrons were the same one from him as seriously as I took the observation that positrons could simply be represented as electrons going from the future to the past in a back section of their world lines. That, I stole!" - Richard P. Feynman – Nobel Lecture, December 11, 1965
"There is lots of silly there. For one, you can't ignore greenhouse gases absorbing radiation from the ground, and radiating a fair bit of it back. If you do, you find that that solar heating alone cannot keep the surface at a toasty 288 K."
I'm still waiting for a proof of this.
Math is not my strong suit. Would you please explain what this post means in English?
Ah, but all electrons are exactly alike. They can have different momenta, energy,etc, but fundamentally, they are the same.
Yes, exactly alike, except for... their quantum state (that's what we mean by energy, momentum, etc.) ;-)
Photons can be even exactly alike in this sense. Like all of them in the same oscillation mode of a laser.
In fact, John Wheeler once suggested that that all electrons might actually be the same particle!
He wasn't the only one. In a rather different way, the Pauli exclusion principle can only be understood by looking at the wave function of all electrons together. It will be antisymmetric under interchange of any two of them. (So you could say that any two electrons are "anti-alike").
Another interesting, and perhaps related, point is the "Dirac Belt trick", seemingly suggesting that every electron is "Belted" to the rest of the universe.
See also the Motion Mountain. Great resource.
:wq
Oh innocent young hares, quantum denial is a flourishing business. Some folk even make a pile of money on it. You could, for example, look at crank.net's section on quantum or, as Eli sometimes does, get thee to the hydrino discussion group where you get to deal with Randy Mills, the Greatest Mind in Cranbury, New Jersey.
Eli did enjoy the Wheeler story tho=:>
jae, it has been explained to you. The amount of energy reaching the surface from the sun is not sufficient to maintain the temperature of the surface if for no other reason that the emissivity in the IR is much higher than the emissivity in the visible and near IR. Much of the emitted IR radiation has to be re-radiated from the atmosphere back to the surface in order to maintain our toasty existence.
Anyhow welcome. Feel free to quibble.
jae, once more, lentissimo e con amore.
Go to the Dave Archer's applet.
First, set the water vapour scaling to zero. Keeps it simpler. Then, submit a calculation. Your instrument is looking down from 70 km.
Do you see the broad CO2 absorption band around wavenumbers 500-800? That's the longwave heat radiation that's not coming out.
Now, go down to ground level (height = 0), and make your instrument look up. Submit calculation.
Do you see the CO2 emission band around wavenumbers 500-800? There's your missing heat energy, coming straight back to the ground. Most of it didn't even make it up more than a few hundred metres...
The back-end software is an industrial strength package called MODTRAN used much by remote sensing folks. Lots of expensive equipment would be in very deep chicken doodoo if this didn't calculate, well, "realistically" :-)
:wq
The statement by Kenneth G. Libbrecht, Chairman of the physics department at Caltech, (quoted above from the Snowflake page)
"our understanding of elementary particles indicates that all electrons are exactly, precisely the same"
does not imply that all electrons (or even any two) share the same quantum state (which they can't, by the Pauli Exclusion Principle)
Libbrecht's use of the phrase (and the usual use of the phrase by physicists, at least) "all electrons are exactly alike" means that they all share precisely the same charge, mass, magnetic moment, (ie, intrinsic properties).
They do not differ one iota intrinsically and are fundamentally indistinguishable from one another.
If electrons were not all exactly alike, I chemistry would undoubtedly be a more difficult subject!
"jae, it has been explained to you. The amount of energy reaching the surface from the sun is not sufficient to maintain the temperature of the surface if for no other reason that the emissivity in the IR is much higher than the emissivity in the visible and near IR. Much of the emitted IR radiation has to be re-radiated from the atmosphere back to the surface in order to maintain our toasty existence."
I still don't understand. What does the emissivity have to do with it? Are you talking about emissivity from the surface? From the atmosphere? You don't think the air and water heat up and retain heat?
Jae
Can't get much more simple than this
It explains "what emissivity (lamda) has to do with it" and tells you what the approximate temp would be if emissivity (of the atmosphere) were zero (ie, if there were no greenhose effect)
The math is actually very simple (junior high algebra), especially if you set lamda to zero (no greenhouse effect).
All you need to do is solve
the equation " sigma T^4 = S"
for the temperature T
In other words, take the 4th root of " S/sigma "
sigma = stefan boltzmann constant and S is about 240 W per square meter.
You get 255K, which is significantly less than the actual value for the measured mean global temp (about 288K)
sorry, that should have been "greenhouse effect" (but "greenhose effect" works too)
> Here is the beginning of my post. And here is the rest of it.
Are there supposed to be links behind that line?
I looked over at CA -- 41 pages -- and decided no matter how fine the pony may be, I don't want to dig through all that ...
"You get 255K, which is significantly less than the actual value for the measured mean global temp (about 288K)"
Yeah, yeah, but that is the bb calculation that works without an atmosphere.
Where did the lambda equation at the RC link come from?
Jae,
You are are moving the goalposts
Above, you challenged Eli's claim that
For one, you can't ignore greenhouse gases absorbing radiation from the ground, and radiating a fair bit of it back
with the statement that
"I'm still waiting for a proof of this"
I provided the simple proof that demonstrates that without a greenhouse effect (ie, an IR absorbing atmosphere), the earth's average temp would be some 33K cooler than it actually is.
And now you are asking for something different.
This makes me wonder if you are genuinely interested in why the greenhouse effect is necessary to explain the discrepancy between actual surface air temp and the temp that would occur if eath had no IR absorbing atmopshere.
It certainly appears that you are playing a game here rather than expressing a genuine interest.
Math is not my strong suit. Would you please explain what this post means in English?"
Ya know, jae.
if you really can't take the fourth root of a number, you really should go back to junior high and quit bothering Eli.
That's pathetic.
What about the calculation that the Temp of Venus is purely due to Mass of atmosphere times Gravity. No need to worry about water vapour?
It turns out that there is a small amount of water vapor in the Venusian atmosphere, and this pretty much completely closes the IR window.
Now, if you had actually read what Eli wrote, you would have recognized that greenhouse gases maintain the temperature of the ground by re-radiating emission from the surface back to the surface. The adiabatic lapse rate depends on the temperature of the surface. It ain't one thing OR another, it's one thing AND another.
jae aks "Where did the lambda equation at the RC link come from?"
The real Climate post linked to above indicates where it comes from under the heading "The Greenhouse Effect".
The first equation:
S + lamda x A = G
means that at equilibrium (ie, energy in = energy out), the total energy absorbed by the earth's surface per square meter per second -- S watts per square meter from the sun plus "lamda x A" watts per square meter from the atmosphere (back toward earth) -- is equal to the total amount of energy radiated by the earth per square meter per second.
The lamda factor (emissivity) comes in because the atmosphere is not a perfect black body in the IR. In words, it only absorbs (and radiates) a certain fraction (lamda) of the radiation absorbed (and emitted) by a black body at the same temperature (which equals a constant (sigma) times temperature (T) raised to the fourth power -- by the stefan boltzmann radiation law)
The second equation
lamda x G = 2 x lamda x A
means this:
The atmosphere, which is also in equilibrium (though at a different temp from the earth) absorbs a certain fraction (lamda) of the energy emitted by the earth per square meter per second ("G") and re-emits this equally in two directions -- to space and back to earth. Again, there is a factor of lamda involved for the energy radiated by the atmosphere (explained above)
Finally, the third equation,
S = lamda x A + (1- lamda) x G
means this:
The earth-atmosphere system taken as a whole absorbs S watts per square meter from the sun (top arrow directed down) and re-radiates the same amount (the two top arrows directed up added together) back to space, equal to the energy emitted by the atmosphere to space (again per square meter per second) plus the fraction of the (IR) energy emitted by the earth that went right through the atmosphere without being absorbed by the atmosphere ( 1-lamda) x G.
As explained above:
If you wish to find the temperature of the earth with no greenhouse effect (ie, with no IR absorbing (and emitting) atmosphere, simply set the value of lamda to "0" and solve the first equation S = G, where G= sigma T^4 for the temperature of the earth T. In other words, take the fourth root of S/sigma (you get about 255K)
As indicated in the real Climate post, this is really the simplest model of the earth with an atmosphere and the fact that it yields a value so close to the actual global average temp of the earth's surface (288K) is somewhat fortuitous.
But the one thing it does tell you without any question whatsoever is that without a greenhouse effect, the earth would be significantly cooler than it is.
anon:
"You are are moving the goalposts"
Nope, I'm just starting at the 20-yard line, again, to try to understand this better. Thanks for finally answering my question in your later post. Now, what is the value of A and how is it calculated? If it is just calculated from SB using 288 K, we've got some serious circular reasoning going on, IMHO.
Erm..."Another striking difference is the absence of H2O on Venus. How can this be explained?"
http://books.google.com/books?id=2ykUzupXUKgC&pg=PA218&lpg=PA218&dq=H2O+on+venus&source=web&ots=YB74FyeNWw&sig=dwzIzY0lZpppxIAm2y3KbOXoz48&hl=en&sa=X&oi=book_result&resnum=4&ct=result
jae, I really don't think you are being honest here.
Your initial question was essentially "Why the need for the greenhouse effect?"
Let me remind you what you said because you have so quickly forgotten:
"I'm still waiting for a proof of this":
[Eli's statement that] "you can't ignore greenhouse gases absorbing radiation from the ground, and radiating a fair bit of it back"
And your second question was "Where did the lambda equation at the RC link come from?"
which I just explained.
If you are really trying to learn, you are taking the wrong approach here because it looks to me more and more like what you are doing is what most people do when they deny AGW: play silly word games.
And, no, emissivity of the atmosphere is not simply determined by plugging in 288k to the simple equation above and solving.
It's obvious that this would be circular reasoning -- to say nothing of ridiculous.
What do you take these scientists for, idiots or just frauds?
It's insulting and i would suggest that if you actually want answers in the future, you cease and desist from these sorts of implications.
anon:
"jae, I really don't think you are being honest here.
Your initial question was essentially "Why the need for the greenhouse effect?"
Let me remind you what you said because you have so quickly forgotten:
"I'm still waiting for a proof of this":"
I'm not trying to be coy, obtuse, funny, etc. My interest is what the "greenhouse effect" really is. I realize there is a "greenhouse effect," in the sense that the planet is warmer with an atmosphere than it is without one. What I'm trying to be more certain of is just what causes this.
Again, where did A in the equation come from?
Anyone got the wavelength, and quantum of the Earths emissivity?
Jae says "I realize there is a "greenhouse effect," in the sense that the planet is warmer with an atmosphere than it is without one. "
Oh, really?
then, what, precisely was the point of your request for a proof of eli's statement "you can't ignore greenhouse gases absorbing radiation from the ground, and radiating a fair bit of it back"
if you already "realized" there is a greenhouse effect?
...and by the way, a minor point of English (or more precisely, Greek)
There is no "lamb" in "lamda".
I think I am beginning to see the point of Eli's post (but at least no one can say i didn't try)
anon: You either have trouble reading, or I have trouble getting my point across, because you just don't get it. But for now, just tell me where the equation with "A" in it comes from and how "A" is determined.
sorry, jae, but it's pretty obvious to anyone who reads what is above that if anyone doesn't get it, it is you.
my first assessment was correct.
go back to junior high and learn to think.
anon: perhaps you need to go to charm school for awhile, LOL. I have a strong hunch that you don't understand as much as you think you do.
... and I have a strong hunch from what you said above that you are a liar.
So does that mean you really have a strong hunch that I understand more than I think I do?
You seem to be agreeing that the entire Temperature gradient is derived solely as a function of Gravity. Well done.
No lamb in lambda? I beg to differ (as does my LaTeX compiler).
LaTeX is a sickness of physicists, wanna be printers and control freaks (YMMV) but yes, we like the lambs as long as they don't hog the goodies
In denialoworld, Jupiter and Venus weigh the same. Precious. More please.
Saturnian.
No lamb in lambda? I beg to differ (as does my LaTeX compiler)
Since when did the guy who created the LaTeX compiler become the definitive authority on Greek?
Probably about the same time that some Microsoft Geek became the definitive authority on English grammar.
While the Greeks had class, the geeks are just crass.
Anon: Google is your friend:
http://en.wikipedia.org/wiki/Lambda
Jae,
The greenhouse effect works because some gases absorb infrared light but are transparent (or mostly so) to sunlight. A simplified picture of how the greenhouse effect works would be as follows:
1. Sunlight passes through the atmosphere and heats the ground.
2. The ground gives off infrared light.
3. The greenhouse gases absorb the infrared light.
4. The greenhouse gases heat up because of the infrared light they have absorbed.
5. The greenhouse gases radiate infrared light.
6. Some of the infrared light from the greenhouse gases goes down and strikes the Earth.
7. The Earth heats up a little more.
That's basically how the greenhouse effect works -- you've got both sunshine and "atmosphere shine" heating the Earth. In fact, the Earth's surface actually gets more heating from the atmosphere than directly from the sun! (about 324 watts per square meter compared to 168 W/m^2).
Barton:
The first 6 steps are correct. Step 7 violates the second law of thermodynamics. You can't heat a warm surface with a colder one. I don't care how many watts you generate from the colder surface, it cannot heat a warmer one. I know it's counterintuitive, but I think it's demonstrably true. See the "Goodbye radiation, hello convection." thread on the CA Message Board (under the Physics Subject).
However as has been pointed out to you many times the exchange of heat from a colder to a warmer body can effect the equilibrium temperature of the warmer one.
It goes like this:
-The surface is at ~290 K. It radiates ~400 W/m2. In addition there are losses from latent heats (maybe another 100 on average).
-The average solar power absorbed by the surface is ~190 W/m2, call it 200 W/m2.
-That means, neglecting latent heats, if there is no radiation from the atmosphere absorbed by the earth, the surface will cool until the net outflow of radiation in the IR matches the radiation absorbed by the sun.
-Do the math E = 200 W/m2 = $sigma; Tn^4, so the temperature of the surface will reach an equilibrium at 244 K. If you include convection, which is strictly a loss from the surface, the temperature would go even lower.
-OTOH, if 200 of the 400 W/m2 radiated in the IR are returned to the earth from the colder atmosphere, there is a balance between energy absorbed at the surface, Sun + Atm Return =200 +200
and surface radiated = 400 W/m2.
-There is still a NET heat flow from the warmer surface to the colder atmosphere (400 - 200 W/m2) so the second law is obeyed
-In short, you are not only wrong, you are in deep denial.
Numbers at eoearth
Anonymous said:
Step 7 violates the second law of thermodynamics. You can't heat a warm surface with a colder one. I don't care how many watts you generate from the colder surface, it cannot heat a warmer one.
Actually, that's not correct. Any light absorbed by an object will heat it, even if the thing it's coming from is at a lower temperature. The object has no way of knowing what temperature the light falling on it originates from.
"Actually, that's not correct. Any light absorbed by an object will heat it, even if the thing it's coming from is at a lower temperature. The object has no way of knowing what temperature the light falling on it originates from."
Yeah, yeah, that's just where the ERROR is in the whole AGW nonsense. You can send all the radiation you want from a cooler object to a warmer one, but it will NOT HEAT IT. That violates the second law of thermodynamics.
I hope anonymous 7:26 is joking, because otherwise their teachers should be forming a queue at their front door to demand apologies for bringing them into disrepute.
If they are not joking, perhaps they can tell us what heat and radiation are, and how heat is transfered by an electric fire.
I can´t Thank You enough for debunking this dubios article.
BTW Anybody intrestet in Reading O. G. SOROKHTIN original Paper in german can leave a comment, on request I will leave a Link.
I have a Comment to make and I would appreciate if you could correct this on your Site. It doesn´t change the argumantation you just cited wrong.
in Eq(2) you define Te as the Surface Temperature, while it is in the paper the radiation Tempeture (as statet Equation 2 in the original Paper). Please Correct this to help other in the Argumentation.
Thanks!!
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