Falsifying the Atmospheric CO2 Greenhouse Effect: G. Gerlich & R.D. Tscheuschner

[Andre]

G. Gerlich, R. D. Tscheuschner (2009) Falsification Of The Atmospheric CO2 Greenhouse Effects Within The Frame Of Physics. International Journal of Modern Physics B, Vol. 23, No. 3 (30 January 2009), 275-364 (World Scientific Publishing Co.)

see:

http://www.worldscinet.com/ijmpb/23/2303/S02179792092303.html

there is also the freely available post-print version 4.0 from the preprint server of the Cornell University: http://www.arxiv.org/abs/0707.1161v4

Abstract:

The atmospheric greenhouse effect, an idea that many authors trace back to the traditional works of Fourier (1824), Tyndall (1861), and Arrhenius (1896), and which is still supported in global climatology, essentially describes a fictitious mechanism, in which a planetary atmosphere acts as a heat pump driven by an environment that is radiatively interacting with but radiatively equilibrated to the atmospheric system. According to the second law of thermodynamics such a planetary machine can never exist. Nevertheless, in almost all texts of global climatology and in a widespread secondary literature it is taken for granted that such mechanism is real and stands on a firm scientific foundation. In this paper the popular conjecture is analyzed and the underlying physical principles are clarified. By showing that (a) there are no common physical laws between the warming phenomenon in glass houses and the fictitious atmospheric greenhouse effects, (b) there are no calculations to determine an average surface temperature of a planet, (c) the frequently mentioned difference of 33 degrees Celsius is a meaningless number calculated wrongly, (d) the formulas of cavity radiation are used inappropriately, (e) the assumption of a radiative balance is unphysical, (f) thermal conductivity and friction must not be set to zero, the atmospheric greenhouse conjecture is falsified.

Any comments?

 

[Xnn]

Andre;

This is just another straw man argument.

First they suggest that the Earth is in radiative equilibrium.
Equilibrium by definition implies no overall change.
Then they go on to "prove" that the Earth isn't really warming.

So, no real surprise here. Misrepresent the science and then "prove" that it is wrong. Classical straw man.

Does the publisher require peer review or do they print everything that's "scientific"?

 

[Andre]

Perhaps you need to rethink a little

http://www.worldscinet.com/ijmpb/ijmpb.shtml

 

[Xnn]

Suggesting that the Earth is in radiative equilibrium is a straw man.

 

[jostpuur]

From the beginning of the abstract:

The atmospheric greenhouse effect, an idea ... ...which is still supported in global climatology, essentially describes a fictitious mechanism, in which a planetary atmosphere acts as a heat pump driven by an environment that is radiatively interacting with but radiatively equilibrated to the atmospheric system. According to the second law of thermodynamics such a planetary machine can never exist.

Did I understand correctly, that these guys are claiming the atmospheric greenhouse effect to be violating the second law of thermodynamics? So they are not claiming, that the magnitude of atmospheric greenhouse effect would have been estimated incorrectly, but that the atmospheric greenhouse effect itself is impossible? Looks like extreme incompetence to me.

 

[WeatherRusty]

A heat pump? NO, they have the concept of the greenhouse effect reversed. It does not produce heat, it slows the dissipation of heat to space. The atmosphere cools off more slowly by the presence of molecules absorbing terrestrial infrared radiation. The atmosphere is constantly radiating away heat energy in accordance with the Second Law. Without continued solar irradiance the atmosphere cools, greenhouse effect or not.

 

[sylas]

G. Gerlich, R. D. Tscheuschner (2009) Falsification Of The Atmospheric CO2 Greenhouse Effects Within The Frame Of Physics. International Journal of Modern Physics B, Vol. 23, No. 3 (30 January 2009), 275-364 (World Scientific Publishing Co.)

see:

http://www.worldscinet.com/ijmpb/23/2303/S02179792092303.html

there is also the freely available post-print version 4.0 from the preprint server of the Cornell University: http://www.arxiv.org/abs/0707.1161v4

[...]


Any comments?

It's incredible to me that this paper actually managed to get published; albeit in a low impact journal, and as an invited "review" article which apparently does not have the same peer-review procedures as research articles. The subject matter is a poor fit with the journal; I very much doubt that this paper could ever have survived a normal peer review process. But there you go. I'm speculating. All we can really know for sure is the content of the paper as given.

I claim it is riddled with errors. Rather than attempt a comprehensive rebuttal, I'll single out limited specific errors in the paper.

Here's my first.

From the arxiv preprint, top of page 65, we read:

According to the consensus among global climatologists one takes the -18^oC computed from the T⁴ average and compares it to the fictitious Earth's average temperature of +15^oC. The difference of 33^oC is attributed to the natural greenhouse effect. As seen in Equation (83) a correct averaging yields a temperature of -129^oC. Evidently, something must be fundamentally wrong here.​

What the authors describe as the "correct" calculation is bizarre. It comes from section 3.7.4.

First, they consider the energy per unit area for each part of the globe coming from the Sun. This is done correctly. Hence the portion of the Earth which is directly facing the Sun is given a full solar constant. Higher latitudes have this scaled by the cosine. The back of the globe (night) has no radiation at all.

They compute the solar constant as σ.5780⁴/215², which comes to 1369 W/m²; about correct. They use a factor of 0.7 for ε (table 12 on page 64) which corresponds to the effect of albedo. Hence the incoming solar radiation is treated as 958.4 W/m² for a plane surface facing the Sun; a reasonable figure.

They then contrast two ways to proceed. One way is to integrate the incoming energy of the surface of the globe, and then calculate a temperature which can be given to the whole globe that would radiate out that same amount of energy again. Another way to proceed is to take each point on the globe individually as having the temperature to radiate away what it receives from the Sun at that point; and then average this over the whole globe. They call this second method the "correct" method. Their so-called correct method gives a temperature of 0K absolute to the night of the planet, and a temperature of about 360K, or 87C, to the portion of the globe facing the Sun.

The authors' so-called "correct" calculation is indeed calculating an average temperature, obtained by integrating an imputed temperature over the whole globe. This integration over the surface gives a value of about 144K, or -129C for the average temperature imputed to the simple model of a globe.

The feature of this imputed temperature is that it is just what is required to radiate (as a blackbody) the radiation coming from the Sun at every point. Now this is of course not a physical model of the Earth. Points on a planet do not instantaneously achieve thermodynamic equilibrium with the Sun's incoming radiation; even the Moon, with no atmosphere and very little heat transport across the surface, does not instantly reach absolute zero on the night side! The calculation provided by the authors can be sensibly understood is a lower bound on average temperatures; assuming radiative balance with the Sun. With any sharing of heat energy around the globe, while maintaining energy balance with the Sun, will give a higher average temperature. (You can show this with Holder's inequality, also used by the authors on page 65).

Now the other extreme model is to calculate a temperature such that if every point on the globe has that same temperature, then the globe remains in energy balance. This is the calculation that the authors disparage as "incorrect". Here, you calculate the average amount of energy radiated per unit area, and find the temperature this corresponds to. This is also called the "effective" temperature. It is equal to 2^0.5*1.25 (1.768) times the authors' "physical" temperature. (Compare equations 81 and 83). This works out to about 255K, or -18C. You can see the numbers -129C and -18C compared in table 12.

The proper implication of these numbers is that if you integrate temperatures over the surface of a globe which is radiating away the same energy it receives from the Sun, you'll get a value more than -129C and less than -18C.

Of course, if you integrate over the Earth's surface in reality, you get a number that is substantially more than -18C! It really doesn't matter whether you integrate temperature, or the fourth power of temperature. Whichever is chosen, you'll get an average of more than -18. That is… the Earth's surface is radiating more than what is required to balance solar radiation. But this IS the effect called "atmospheric greenhouse"!

Physically, this is because we have an atmosphere, which is heated from the surface. The atmosphere is (by thermodynamics) cooler than the surface, and the radiation that escapes into space is mostly from this cooler atmosphere. This is (by the first law) in long-term balance with solar radiation. The atmosphere radiates in all directions, of course. It radiates out into space, and also down to the surface; and this means the surface gets more energy. There's the solar energy (most of which passes through the atmosphere just fine) plus also the energy radiated from the atmosphere. The surface is in balance with this total… which is more than what you'd have without an atmosphere. This is what is called the atmospheric greenhouse… a poor choice of terms given that the physics is quite distinct from a glass greenhouse; but it is certainly physically real.

At the end of section 3.7.6, page 66, the authors make two claims. The speaks of a physically incorrect assumption of radiative balance. That's ludicrous. By the first law, there is necessarily a long term balance between the energy arriving from the Sun and being radiated from the planet. It is a physically correct implication that the Earth radiates an amount of energy into space that is equivalent to that of a blackbody at -18C.

The second claim speaks of effective radiating temperature being higher than measured averages. That is correct, and the authors are the ones who do not take this into account. The measured averages over the surface of the Earth are much more than -18C. Therefore the surface is radiating more than what you would get from a globe at -18C! Therefore the energy being radiated from the Earth's surface is MORE than the energy you get from the Sun. That IS the greenhouse effect, right there.

Good grief. It staggers me that this got published, but so be it. I am pretty sure it was an invited paper which was not given the kind of thorough technical review that usually maintains the quality of a journal.

Cheers -- Sylas

 

[Xnn]

Maybe Gerlich and Tscheuschner forgot that the Earth rotates!

That would be one way to come up with absolute zero for the night time temperature.

 

[sylas]

Maybe Gerlich and Tscheuschner forgot that the Earth rotates!

That would be one way to come up with absolute zero for the night time temperature.

That, and also the assumption that there is no transport of heat from one part of the planet to another. Now of course, they know quite well that this is only a simplified model. They don't suggest that there really is an absolute zero of temperature on the reverse side, and that is not my criticism.

What they do has its own rather curious meaning. Effectively, what they are doing is to take the energy arriving from the Sun, and average the energy to the power 0.25 over the globe. With any redistribution of energy -- either by the fact that it takes a bit of time to heat up and cool down, or by the fact that heat transports from one region to another -- the average of energy to the power 0.25 will increase. The number they get is thus a strong lower bound on temperature of a globe with uneven temperatures, but radiating at each point as a blackbody.

The other approach is to average energy over the globe. (You can then get a temperature from this energy by Stefan-Blotzmann, which is called T_eff). The key point is that there is a very useful feature of averaging the energy. Because of the first law, any redistribution will continue to have the SAME average energy. It's not a lower bound, or an upper bound, but an invariant.

That's why T_eff is a far more useful quantity.

If you do take a simple mean temperature over the whole surface, you are bound to get a smaller value than T_eff. The authors correctly point this out as well, but completely fail to grasp its relevance. When you integrate temperatures over the Earth's surface, you get a value GREATER than the expected -18 of T_eff. That is, the surface is significant warmer than we should expect from the solar input alone. The difference is the effect of an atmosphere, and it is called "atmospheric greenhouse". But it's not like a glass greenhouse; it is a consequence of the fact that the atmosphere is warmed from the surface.

It up within the atmosphere where you find the temperatures corresponding to the effective temperature from solar radiation. This is cooler than the surface, because it is warmed from the surface. Hence, the surface is warmer than the effective radiating temperature of the planet... warmer than it would be without an atmosphere that absorbs energy from the surface. And no; that is not a contradiction of the second law, which appears to be another error made in the paper.

Cheers -- Sylas

 

[Mike Davis]

Lunar Surface Temperatures
Temperatures on the Lunar surface vary widely on location. Although beyond the first few centimeters of the regolith the temperature is a nearly constant -35 C (at a depth of 1 meter), the surface is influenced widely by the day-night cycle. The average temperature on the surface is about 40-45 C lower than it is just below the surface.

In the day, the temperature of the Moon averages 107 C, although it rises as high as 123 C. The night cools the surface to an average of -153 C, or -233 C in the permanently shaded south polar basin. A typical non-polar minimum temperature is -181 C (at the Apollo 15 site).

The Lunar temperature increases about 280 C from just before dawn to Lunar noon. Average temperature also changes about 6 C betwen aphelion and perihelion.

From:
http://www.asi.org/adb/m/03/05/average-temperatures.html

Without the atmosphere effect this is what the Earth would be like. That is from the solar input alone. So the atmosphere effect restricts the incoming and outgoing warmth.

 

[sylas]

Lunar Surface Temperatures
Temperatures on the Lunar surface vary widely on location. Although beyond the first few centimeters of the regolith the temperature is a nearly constant -35 C (at a depth of 1 meter), the surface is influenced widely by the day-night cycle. The average temperature on the surface is about 40-45 C lower than it is just below the surface.

In the day, the temperature of the Moon averages 107 C, although it rises as high as 123 C. The night cools the surface to an average of -153 C, or -233 C in the permanently shaded south polar basin. A typical non-polar minimum temperature is -181 C (at the Apollo 15 site).

The Lunar temperature increases about 280 C from just before dawn to Lunar noon. Average temperature also changes about 6 C betwen aphelion and perihelion.

From:
http://www.asi.org/adb/m/03/05/average-temperatures.html

Without the atmosphere effect this is what the Earth would be like. That is from the solar input alone. So the atmosphere effect restricts the incoming and outgoing warmth.

That's a great example, Mike!

The moon rotates much more slowly than the Earth, and so the temperatures should actually come fairly close to those given by what Gerlich and Tscheuschner prefer.

The solar constant is about 1370 W/m². The albedo of the moon is roughly 0.12, and so the surface face on to the Sun should tend to absorb about 1205 W/m².

Using Stefan-Boltzmann, these correspond to temperatures of 394K (121C) and 381K (109C).

That's pretty dashed close to the daytime numbers you have quoted of 107 (av) and 123 (peak)! The peak would be a dark spot face on to the Sun, with near complete absorption. The 107 is about right for the central daylight region, given albedo 0.12.

The night side does not drop to absolute zero. But since the energy varies as the fourth power of temperature, we have the radiation from the lows you have mentioned as follows:

-153C radiates about 12 W/m². -181C radiates about 4 W/m². And -233C radiates about 0.15 W/m².

Cooling tails off, of course, as the rate of energy radiation drops; and these temperatures have fallen so far that the radiation is less than 1/100 of the peak full daylight value. So in fact the Moon is pretty dashed close to the distribution that is used by Gerlich and Tscheuschner. This is no surprise. If the Moon was made of iron (conducts heat well) and rotated rapidly, then we should expect all the temperatures to equalize or close to it, which would lead to temperatures around -3 C. (The T_eff for albedo of 0.12). The value calculated by Gerlich and Tscheuschner's method would be around -120C. However, because the darkside of the moon has temperature significantly above absolute zero, their method works out as a very strong lower bound. The average lunar temperature should be between these values of -12OC and -3C, as there is no greenhouse effect to warm things up.

The page you have cited is not consistent on mean surface temperatures. It speaks of -35 below the regolith, and a surface that is 40 to 45 cooler. That's a mean surface of -75 to -80. But the related page at the same site http://www.asi.org/adb/02/05/01/surface-temperature.html specifically gives -23C as a mean surface value. I don't know what's wrong there. But theoretically, -3C should be an upper bound on the mean surface temperature obtained by integrating temperature over the surface. -23C sounds like a credible value for an average surface temperature. It is equal to mid point of the average day and the average night temperature as given by another page: http://www.solarviews.com/eng/moon.htm.

Since there is such variation in temperature from point to point, we should expect the average value, whatever it is, to be significantly less than T_eff of -3C. And because the night side is well above absolute zero, we should expect the average to be substantially more than -120C.

This is in contrast to the surface of the Earth, which (fortunately for us!) has an atmosphere to keep things warmer. The effective value of the planet of -18C is actually expressed high in the atmosphere, while the "atmospheric greenhouse" effect keeps things on the surface with a much warmer average of about 15C.

 

[Mike Davis]

Sylan:
You made the statement that the atmosphere warms the earth. This article proves that the atmosphere restricts the incoming heat from reaching 123C. The atmosphere also restricts the loss of warmth keeping the low temperatures from reaching -233.

That was the points I was bringing up. The oceans and land heat the atmosphere not the other way around.

 

[sylas]

Sylan:
You made the statement that the atmosphere warms the earth. This article proves that the atmosphere restricts the incoming heat from reaching 123C. The atmosphere also restricts the loss of warmth keeping the low temperatures from reaching -233.

That was the points I was bringing up. The oceans and land heat the atmosphere not the other way around.

No, I most certainly did not say that the atmosphere warms the Earth. I said precisely the opposite, just as you have noted. It is the ocean and land, or the surface, which warms the atmosphere. Here again is what I actually said, and note especially the first sentence, which I have placed in bold for emphasis.

Physically, this is because we have an atmosphere, which is heated from the surface. The atmosphere is (by thermodynamics) cooler than the surface, and the radiation that escapes into space is mostly from this cooler atmosphere. This is (by the first law) in long-term balance with solar radiation. The atmosphere radiates in all directions, of course. It radiates out into space, and also down to the surface; and this means the surface gets more energy. There's the solar energy (most of which passes through the atmosphere just fine) plus also the energy radiated from the atmosphere. The surface is in balance with this total… which is more than what you'd have without an atmosphere. This is what is called the atmospheric greenhouse… a poor choice of terms given that the physics is quite distinct from a glass greenhouse; but it is certainly physically real.

It is precisely because the atmosphere is being warmed by the surface that the surface has to be hotter than you would have without an atmosphere! Think about it. Because the atmosphere is absorbing energy from the surface, the energy that eventually escapes into space is mostly emitted from the atmosphere. Therefore it is in the ATMOSPHERE (not the surface) where you have the temperatures that correspond to what is needed to radiate away what we receive from the Sun.

The effective radiating temperature of the atmosphere is T_eff. You can get this by averaging a fourth power. If you average the raw temperature, you'll get something a bit less, depending on how much variation there is in temperature across the globe. This is noted also by Gerlich and Tscheuschner; though they apparently don't understand the implications.

In any case, the atmosphere, at altitudes where most radiation is escaping into space, must have an average temperature of about -18C or less. This is the T_eff for the Earth.

Now... because the atmosphere is being heated from the surface, the surface has to be hotter than than the atmosphere. And it is. This is the greenhouse effect.

Note the difference. When you add an atmosphere, you get a warmer surface than you would have otherwise. This is NOT because the atmosphere is a source of energy. It is because the atmosphere has to be warmed up by the surface, which results in a surface that is warmer than the atmosphere. The atmosphere is what takes up the temperature required to balance solar input.

Pretty much the same thing happens when you cover yourself with a blanket. YOU warm the blanket. So you are warmer than the blanket. But the blanket is what has to match up with external temperatures, which means you end up warmer than you would be without the blanket. NOT because the blanket is a source of energy to warm you, but because it is absorbing energy from you, and then passing it on to the cold outside.

Cheers -- Sylas

PS. Think about your lunar example again. It's a really good one. The Moon is (on average) COLDER than the Earth. This despite having a lower albedo and absorbing more of the light from the Sun! Why? The conventional physical explanation is that the Moon has no atmosphere, and so radiation from the surface has to balance with the solar input. On the Earth, however, it is radiation from the atmosphere which has to balance the solar input. The Earth's surface has to heat up its atmosphere, and so has to be warmer than the atmosphere... which means it has to be that much hotter again than what is required to balance the solar input.

 

[Phrak]

It is precisely because the atmosphere is being warmed by the surface that the surface has to be hotter than you would have without an atmosphere! Think about it.

I would think that the surface temperature would oscillate greatly between day and night, becoming both hotter and cooler than with an atmosphere. What are you talking about?

 

[sylas]

I would think that the surface temperature would oscillate greatly between day and night, becoming both hotter and cooler than with an atmosphere. What are you talking about?

I am talking about the substantial increase in average surface temperature than results from an atmospheric greenhouse effect; since this is the topic of the paper.

The Moon does indeed oscillate greatly in temperature, much more than the Earth, and this is because of our atmosphere... and the ocean... and our shorter day/night cycle.

Any oscillation, of course, goes above and below the average... and just as Gerlich and Tscheuschner say, the average has to be less than T_eff, in the absence of a greenhouse effect. On the Moon, with its low albedo, T_eff is -3 C (on Earth it is -18 C) and the average is something like -23C. The oscillations are about -153C to 107C; a range of 260C.

On Earth, there are two major differences with the Moon. First, we have much more uniformly distributed temperatures, or much smaller oscillations, as you note. The largest swings are inland away from the ocean, and get up to as much as 50 or 60C between day and night. Second, the average surface temperature is substantially higher than T_eff, because the surface is heating up the atmosphere. On Earth, T_eff is about -18C, but the average surface temperature is about 15C. This latter effect is called the atmospheric greenhouse effect. Both effects are real, both are measured, and both follow from conventional thermodynamics applied to each situation.

As far as damping out oscillations is concerned: the ocean is crucial in this regard because of its large heat capacity, which damps out the oscillations a lot. Indeed, the extremes of day and night are comparatively small on the coast, or out at sea. The atmosphere helps to distribute heat between land and sea as well. It's a basic thermodynamic principle that any dynamic process increases entropy... which means it tends to equalize temperatures. The atmosphere and air movement help to shift heat energy from ocean to land, and back again, transferring heat energy from the ocean to the land and night, and from the land to the ocean in the day. Our short day/night cycle also helps.

Now all of this effect of the atmosphere in damping out the oscillations is independent of the greenhouse effect. Consider a hypothetical case, in which our atmosphere was simply oxygen and nitrogen, which are transparent to infrared and to solar radiation. The energy escaping to space would be nearly all radiated direct from the surface. The surface, therefore, would have an average temperature of around -18C (which is T_eff for the Earth). There would be oscillations both above and below this mean; but still damped by comparison with a Moon having no atmosphere to help move heat around.

The other effect, of course, is the greenhouse effect, where the atmosphere absorbs energy from the surface, and where most of the energy radiated into space is from the atmosphere. This means that temperatures which correspond to a radiative balance with the Sun (a consequence of the first law) in the atmosphere must be cooler than the surface temperatures (a consequence of the second law).

That's what I am talking about. The surface heats the atmosphere, on average, which means the surface has to be warmer than the atmosphere, on average. The end result is an average surface temperature significantly greater than -18C, which means that the surface is warmer than it would be without an atmosphere. Without an atmosphere the oscillations, whether large or small, would be about a mean at -18C or less. With an atmosphere such as ours, which is heated from the surface, the mean temperatures are much greater.

Cheers -- Sylas

 

[Mike Davis]

"There's the solar energy (most of which passes through the atmosphere just fine) plus also the energy radiated from the atmosphere. The surface is in balance with this total… which is more than what you'd have without an atmosphere. This is what is called the atmospheric greenhouse… a poor choice of terms given"

This statement about energy radiated from the atmosphere. I took as meaning the atmospere warmed the surface.

With an atmosphere such as ours, which is heated from the surface, the mean temperatures are much greater.

This statement ,which I argree with, shows that the atmosphere restricts the loss of heat.

I guesss I jumped when I read the first statement. When you rewrite your statement it is more acceptable.

Thank you for explaining what you meant.

 

[sylas]

"There's the solar energy (most of which passes through the atmosphere just fine) plus also the energy radiated from the atmosphere. The surface is in balance with this total… which is more than what you'd have without an atmosphere. This is what is called the atmospheric greenhouse… a poor choice of terms given"

This statement about energy radiated from the atmosphere. I took as meaning the atmospere warmed the surface.

With an atmosphere such as ours, which is heated from the surface, the mean temperatures are much greater.

This statement ,which I argree with, shows that the atmosphere restricts the loss of heat.

I guesss I jumped when I read the first statement. When you rewrite your statement it is more acceptable.

Thank you for explaining what you meant.

No problem. I'm currently working on trying to make a basic and comprehensible account of this, and you've been really helpful for cleaning up my wording. Keep pointing out anything that looks wrong. It helps a lot.

Just to underline what I mean above, the second law means that the flow of energy from a hot object to a cold one must be greater than the flow of energy back from the cold object to a warm one. It does not mean there's no flow at all from cold to hot. So even though the atmosphere is warmed from the surface, there is still some energy flowing back against the overall flow.

By the second law, the flow from Earth's surface into the atmosphere has to be more than the flow from the atmosphere into the surface. Typical numbers on Earth are that about 470 W/m² go from surface to atmosphere, while about 340 W/m² come back. Added to this is solar energy flowing from space into the surface, and into the atmosphere. Typical numbers are 160 W/m² to the surface, and 80 W/m² to the atmosphere. For the energy flowing back out into space, typical numbers are 210 W/m² going into space from the atmosphere, and about 30 W/m² coming direct from the surface.

$$\begin{array}{l|c|c|c|c} (W/m^2)& \mbox{to space} & \mbox{to atmos} & \mbox{to surface} & \mbox{total} \\ \hline \mbox{from space} & & 80 & 160 & 240 \\ \mbox{from atmos} & 210 & & 340 & 550 \\ \mbox{from surface} & 30 & 470 & & 500 \\ \hline \mbox{totals} & 240 & 550 & 500 \end{array}$$​

These numbers are roughly average values, to about single figure accuracy. It's intended as a simple first order picture, not a fully accurate account. You can drill down into endless further details for what goes on in different latitudes, in the ocean or the land, in day or in night, or in different seasons and weather conditions. But over all, the following very basic features are not in any doubt at all, and follow easily from basic thermodynamics. Any credible estimate of energy flow on Earth must have these features.

• The flux of energy inwards is the same as the flux outwards, Drilling down into more detail, there are small imbalances as heat gets absorbed, but physical measurement has the net imbalance as small. For example, there is at present a small net flux of energy into the ocean which is of the order of magnitude one W/m² or so. It's an open research question to measure this more accurately, to measure the variations from place to place and from season to season. From day to day, there is a quite substantial flux into and out of the ocean, with the ocean taking up heat in the day and giving it back at night.
• The surface gets more of its energy from the atmosphere than from space.
• The energy received from space is mostly absorbed at the surface.
• The majority of energy radiated into space comes from the atmosphere.
• The atmosphere gets most of its energy from the surface.
• There's more energy flowing from the surface to the atmosphere than there is coming back from the atmosphere to the surface.
• The total flux at the surface is substantially greater than the total flux from space. This is why an atmosphere leads to a warmer average surface temperature.

 

[adb]

It is easy to find fault in areas of minor detail in a paper as long as that of Gerlich. The point of his paper is that he has shown the "classic" atmospheric greenhouse model as depicted by the IPCC, to be utter nonsense.

Here's the IPCC atmospheric greenhouse model:
https://www.msu.edu/course/isb/202/ebertmay/drivers/ipcc_greenhouse.jpg
(IPCC 2001)

We may describe this as:

1. A warm body (the earth) radiates heat to a cool body (the atmosphere)
2. The cool body "back-radiates" (IPCC term) heat to the warm body.
3. This process continues perpetually, with heat flowing round and round in a continuous cycle.
4. The result of this perpetual process is that the warm body becomes warmer.

What is most amazing is that both alarmists and skeptic scientists have taken the above blatant 2nd Law of Thermodynamics violation at face value for so long.

Many will shout that all bodies radiate ... yes they do but NETT heat flow is always from hot bodies to cool bodies (without the input of work), not the reverse. Note also that the 2nd Law does not care about the wavelength of radiant heat.

Atmospheric gases do absorb radiation from the sun and the earth. NETT radiation from the cool daytime atmosphere is to space. The Sahara desert in daytime has a very low "greenhouse gas" concentration above it, yet contrary to greenhouse theory, it is a hot place rather than a cool place.

Night time, rotation of the earth, convection, conduction, latent heat all add greatly to the complexity of climate model. However the basic daytime atmospheric greenhouse model as presented by the IPCC and most textbooks, is nonsense.

 

[jostpuur]

It is easy to find fault in areas of minor detail in a paper as long as that of Gerlich. The point of his paper is that he has shown the "classic" atmospheric greenhouse model as depicted by the IPCC, to be utter nonsense.

No, instead they have shown that they don't understand the simplest things about physics.

adb, let me repeat your argument with winter jackets: "When I go outside in winter wearing a thick jacket, the outer layer of the jacket will be cooler than the inner layer. Therefore there will not be heat flow from outer layer to inner layer, but instead from inner to outer. Therefore the hypothesis that the jacket would keep me warmer violates the second law of thermodynamics."

Do you see how wrong that is? And how same it is with your greenhouse effect denying deduction?

 

[WeatherRusty]

2. The cool body "back-radiates" (IPCC term) heat to the warm body.

Have you considered the possibility that at night over land the surface can become cooler than the atmosphere? This in fact occurs as a result of "radiational cooling". This loss of thermal energy from the surface at night is reduced by a humid atmosphere. One of the "fingerprints" of greenhouse warming is warmer nighttime temperature over land.

 

[adb]

No, instead they have shown that they don't understand the simplest things about physics.

adb, let me repeat your argument with winter jackets: "When I go outside in winter wearing a thick jacket, the outer layer of the jacket will be cooler than the inner layer. Therefore there will not be heat flow from outer layer to inner layer, but instead from inner to outer. Therefore the hypothesis that the jacket would keep me warmer violates the second law of thermodynamics."

Do you see how wrong that is? And how same it is with your greenhouse effect denying deduction?

Heat flows from your warm skin to the outside of your jacket (cool body) mainly by conduction. Heat flows from the cool outside of your jacket to the cooler surroundings mainly by convection. This is as dictated by the 2nd Law.

The temperature of your skin is not controlled by "back radiation" or "back conduction" as you suggest.

The skin surface, and jacket surface adopt a temperature related to heat transfer from the inner body; conduction to the surface of the jacket; and convection to the surroundings.

Perhaps you can explain how your understanding of the simplest of physics generates a "back conduction" to warm the body ?

 

[sylas]

Hi adb. Your post is very timely, as you bring up precisely the next point I was thinking of considering in the Gerlich and Tscheuschner paper. This is another case in which Gerlich and Tscheuschner get elementary thermodynamics wrong.

I see some other posters have given good concise comments that may help show where your analysis fails. In the meantime, I've been working on this longer post.

As an aside, I'll note that this paper seems to have a lot of popular interest mainly because it feeds into widespread public skepticism about so-called "global warming". That particular topic is one that seems to bring up a lot of passions and vehemence. There's a place for that, of course, but I'm hoping to avoid the whole question of changing climate in this thread. Gerlich and Tscheuschner are attempting to refute the conventional physics of a simple fixed atmospheric composition without worrying at all about changes in the atmosphere from one year to the next.

Let's keep that in mind. The question at issue is: the surface of the Earth is warmer – on average – that the surface of the Moon. Why? It's a basic physics problem, and we should be able to give a reasonable answer without any worry at all about how climate is changing. It's only after we have a credible understanding of the physics of the present that there is any basis for looking at the much more subtle problem of changes to present conditions.

Let's look at what you have introduced from G&T.

It is easy to find fault in areas of minor detail in a paper as long as that of Gerlich. The point of his paper is that he has shown the "classic" atmospheric greenhouse model as depicted by the IPCC, to be utter nonsense.

Here's the IPCC atmospheric greenhouse model:
https://www.msu.edu/course/isb/202/ebertmay/drivers/ipcc_greenhouse.jpg
(IPCC 2001)

We may describe this as:

1. A warm body (the earth) radiates heat to a cool body (the atmosphere)
2. The cool body "back-radiates" (IPCC term) heat to the warm body.
3. This process continues perpetually, with heat flowing round and round in a continuous cycle.
4. The result of this perpetual process is that the warm body becomes warmer.

What is most amazing is that both alarmists and skeptic scientists have taken the above blatant 2nd Law of Thermodynamics violation at face value for so long.

The first thing to note here is that the first three points above are simple facts of life. The fourth, however, is incoherent, and stands as a basic confusion made by Gerlich and Tscheuschner. More detail can be added to the picture, but there's no violation of the second law here.

1. The surface of the Earth really is warmer than that atmosphere above it. And the surface of Earth does radiate heat up into the atmosphere. If we consider a more complete picture, the Earth also transfers energy from surface into the atmosphere by convection, and by latent heat of evaporation; but radiant transfer is the largest part of the energy flux from surface to atmosphere. Basically, convection transfers a certain amount, latent heat transfers about three times as much, and longwave radiation transfers four or five times more than latent heat. The net flow of heat and energy is from surface to atmosphere. At night, especially over the land, there can be a low level "inversion" involving a transfer of energy back to the surface from the bottom 500m or so of the atmosphere. This helps damp out the oscillations of temperature between night and day. Over all, however, it is a perfectly sensible observation that the atmosphere is cooler than the surface, and that there is (by the second law) a net flow of energy from the surface up into the atmosphere.
2. A cool body really does "back-radiate" to a warm body. Anything with a temperature will radiate, and this will involve a flux of energy from a cold body to a warmer one. What the second law requires is that the flow back in the other direction from the warm body to the cold one must be larger. The two way transfer of radiant energy exchange between a hot body and a cold one is a standard thermodynamic problem, and it always involves a small flow from cold to warm combined with a larger flow from warm to cold.
3. The exchange of energy between the surface and the atmosphere really does continue perpetually, or at least until the Sun runs out. It has to, by basic thermodynamics, because of the net flow of energy coming in from the Sun, which must be dissipated. But the only energy radiated from the atmosphere is energy it receives from the surface and from the Sun; and ultimately all the energy involved comes from the Sun, with an atmosphere or without.
4. The fourth point "a warm body becomes warmer" makes no sense. G&T are confusing a shift from one stable condition to another with an ongoing increase in temperature. Greenhouse DOES NOT involve making things warmer and warmer in some kind of perpetual motion. It is rather a part of all the more or less stable cycles of temperature. A planet with an atmosphere will be warmer on average than one without, but in both cases the surface temperature cycles from day to night and season to season, without a long term trend. Greenhouse effects result in a higher mean temperature for this dynamic equilibrium.

This point about the dynamic equilibrium is fundamental. Try this highly simplified example, which would be a reasonable exercise for an introductory course in thermodynamics.

• Take a flat surface which radiates as a black body, and which is heated by a bath of incoming radiation at 240 W/m². Calculate the temperature of the surface when it comes into equilibrium with the radiation.
• Add a barrier between the surface and the incoming radiation. Let the barrier absorb 25% of the incoming radiation, and transmit 75%. Let the barrier absorb 80% of the radiation coming up from the surface, and transmit 20% of this. (This is physically sensible. Many materials are transparent to one wavelength and opaque to another.) Assume that the barrier is "thin", with the same temperature on either side, so that it radiates equal amounts of energy in either direction, and that all energy transfer is radiant. Calculate the resulting temperature of the surface.

Note that adding the barrier makes the surface warmer by comparison with conditions without the barrier. This is analogous to a greenhouse effect, whereby an atmosphere makes a planet warmer than it would be without an atmosphere. It does not, however, result in a continuous and perpetual increase in warming at the surface. It just shifts things to a new dynamic equilibrium.

To calculate this correctly, you will have to consider a flow from the surface to the barrier, and also a smaller back-flow from the barrier to the surface.

G&T have confused the "warming" effect of an atmosphere, which is simply a shift of the prevailing conditions to a new and higher mean temperature, with a perpetual motion machine, which actually generates an additional source of energy. The greenhouse involves no extra energy; merely a redistribution of the same energy which comes always from the Sun.

Many will shout that all bodies radiate ... yes they do but NETT heat flow is always from hot bodies to cool bodies (without the input of work), not the reverse. Note also that the 2nd Law does not care about the wavelength of radiant heat.

Quite right; and all of that remains true for an atmosphere that absorbs infrared and transmits visible light. The total energy flow is obtained by taking all the sources of energy, without distinguishing wavelengths. They are all equally important in the energy balance. Different wavelengths can be absorbed or transmitted in different ways, but the second law applies in the same way regardless. You just need to know the energy transferred between the parts of the system, without regard to wavelength.

When an atmosphere absorbs infrared and transmits visible light, it ends up being heated from a planet's surface… because that is where the infrared is coming from. Then, by the second law, it must be cooler than the surface. And it is. Equivalently, the planet's surface must be warmer than the atmosphere. And it is. This is the greenhouse effect.

Atmospheric gases do absorb radiation from the sun and the earth. NETT radiation from the cool daytime atmosphere is to space. The Sahara desert in daytime has a very low "greenhouse gas" concentration above it, yet contrary to greenhouse theory, it is a hot place rather than a cool place.

That's not a contradiction with greenhouse theory at all. The Sahara is extremely cold at night. That is, there are large changes from night to day. The main reason for this is the lack of an ocean to damp out the changes. The drier atmosphere also reduces this damping effect. So in the day time, temperatures rise very quickly, and then drop again at night.

Don't mix up the damping effects of day/night oscillations with the greenhouse effect. They are different things. Also, don't think that that greenhouse concentrations are "very low" in absolute terms. The local greenhouse effect may be reduced, but it's still very much there. Also, because temperatures flow from one part of the planet to another, you simply cannot treat regions in isolation, with greenhouse affecting one place and not another.

Night time, rotation of the earth, convection, conduction, latent heat all add greatly to the complexity of climate model. However the basic daytime atmospheric greenhouse model as presented by the IPCC and most textbooks, is nonsense.

No, it isn't. And do recall, this is NOT about climate change. It is simply about what you should expect the average temperature of a planet to be.

You do agree that the Earth has a higher average temperature than the Moon, I guess. And yet we get the same solar energy. Indeed, the moon absorbs more solar energy than the Earth, because the Earth has ice and clouds and so on that reflects more light without absorption.

If the whole planet was a blackbody at a uniform -18C, then it would be radiating away the same amount of energy as we receive from the Sun. By Holder's inequality, with any redistribution of temperatures that maintains the same net outward radiation, the average temperature will be LESS than -18C. G&T actually get this bit right, without understanding the implication. The surface of the Earth is has an average temperature of more than -18C, and it is, by basic thermodynamics, therefore radiating away more energy per unit time than is received from the Sun. That's a fact. It's data.

Now by the laws of thermodynamics, that energy MUST be coming from somewhere. You cannot propose some kind of perpetual energy machine to supply more energy.

The solution is analogous to the example I have given you above. There's a barrier, above the surface, which in accord with the laws of thermodynamics generates no new energy. Its effect is to raise the net energy flux at the surface above what you would have without the barrier.

Cheers -- Sylas

 

[jostpuur]

I thought that my jacket example would help understanding the mistake in the greenhouse effect denying deduction, but it seems that I forgot one of the main rules of the debating: "If somebody doesn't understand one simple thing, he probably doesn't understand other simple thing either."

It is not necessary to understand details of interactions of various layers of the atmosphere and the ground, to understand the greenhouse effect. When there is more greenhouse gases, there is less heat radiation from Earth to the space. When there is less heat radiation from Earth to the space, the Earth is left warmer. So, when there is more greenhouse gases, the Earth is left warmer. If somebody disagrees with this, he or she is disagreeing with the first law of thermodynamics!

adb, you want to try to explain how the temperature of the Earth would not be affected by the amount of heat radiation the Earth radiates to the space? That's pretty difficult if you want to obey the first law of thermodynamics.

 

[Xnn]

1. A warm body (the earth) radiates heat to a cool body (the atmosphere)
2. The cool body "back-radiates" (IPCC term) heat to the warm body.
3. This process continues perpetually, with heat flowing round and round in a continuous cycle.
4. The result of this perpetual process is that the warm body becomes warmer.

What is most amazing is that both alarmists and skeptic scientists have taken the above blatant 2nd Law of Thermodynamics violation at face value for so long.

It is true that more heat cannot spontaneously flow from something at lower temperature to something else at higher temperature. However, it is also true that all objects emit heat in the form of radiation of various wavelenghts due to their temperature.

In the case of the Earth's surface and the atmosphere, the Earth radiates more energy to the atmosphere than it receives. Thus, there is no perpetuality and no violation of the 2nd law of thermal dynamics.

It would only be a problem (violation) if the amount of energy that the Earth radiated to the atmosphere was always equal the amount that it received. However, we know that the long term average is for the Earth's surface to warm the atmosphere.

The 2nd Law of thermodynamics does not prohibit "back radiation". Instead, it prohibits the "back radiation" from being greater than the "forward radiation". In other words, it's possible for insulation to work and result in objects being warmer than they would be otherwise.

 

[Count Iblis]

To explain the greenhouse effect to lay persons, it is perhaps easier to consider the total energy balance. Then you get rid of all the irrelevant details that the skeptics abuse to make propaganda.


The Earth receives a certain amount of energy from the Sun, so the same amount of energy must be radiated/reflected back into space by Earth, otherwise you don't have equilibrium (it would then become cooler or hotter until you do get equilibrium).


Then we add greenhouse gasses and wait until we again have equilibrium. Since the Sun still delivers the same amount of energy every second, the Earth will radiate away exactly the same amount of energy per second as before we added the greenhouse gasses.


The effect of the greenhouse gas is to make the mean free path of infrared photons shorter (to lay persons you could explain this as looking into a thicker mist). So, the infrared radiation that escapes into space is effectively coming from a bit higher up in the atmosphere. This then means that at this new effective height the temperature must be the same as what it was at the old effective height before the greenhouse gasses were added. But since temperatures decrease as a function of height, this means that the temperature at the surface must have become higher.

 

[Count Iblis]

G. Gerlich, R. D. Tscheuschner (2009) Falsification Of The Atmospheric CO2 Greenhouse Effects Within The Frame Of Physics. International Journal of Modern Physics B, Vol. 23, No. 3 (30 January 2009), 275-364 (World Scientific Publishing Co.)

see:

http://www.worldscinet.com/ijmpb/23/2303/S02179792092303.html

there is also the freely available post-print version 4.0 from the preprint server of the Cornell University: http://www.arxiv.org/abs/0707.1161v4

Abstract:


Any comments?

I'm wondering how many physicists will submit their papers to this journal in the future.

 

[sylas]

I'm wondering how many physicists will submit their papers to this journal in the future.

It's already a very minor journal with a low impact factor. I doubt it will have much effect, as long as this kind of thing is isolated. If the journal becomes known to writers as an easy road to publication of pseudoscientific material on climatology, or as a venue in which debate takes place at such a fundamental level of disconnect with basic physics, then things can go down hill. There are some interesting examples of journals that have gone downhill in this kind of way.

I have emailed the editors to suggest, as politely as I could, that they really should look into this matter.

I had a short reply saying that the best thing would be for critics (like me) to submit a response to their journal as an article; which they would be happy to consider.

I don't plan to do that. I don't think it is appropriate. If this was a real scientific debate, then of course it is the best thing to have competing views expressed in different published papers. This is usual in science, and there are plenty of examples where good published work expresses contrasting views of different experts.

It is not appropriate to have debate on simple first year thermodynamics debated between different papers. With a credible scientific journal, it is the responsibility of the editors to maintain quality by identifying such basic errors in what is submitted before it gets published. With a well run journal, the disagreements aired in the journal are matters of legitimate scientific dispute, not matters of undergraduate homework correction. Or so I think.

The paper is really long. It is full of basic errors from start to finish, but obscured by red herrings and strawmen of the greenhouse theory, or else irrelevant technical jargon which looks impressive at a glance but really shows that they don't know theories apply in a given case, and peppered with outright howlers of error that can be explained if you take the time to pull together the sequence of argument and show where they get it wrong.

A full refutation would be longer than the original (it invariably takes less time to say something that is wrong than to explain why it is wrong) and even then publication is likely to convey the incorrect notion that there really is some kind of scientific debate here.

The need for a response is not for the benefit of working physicists. No one who actually works in atmospheric or planetary thermodynamics is going to be taken in for a second. It's only for the benefit of non-experts or people confused as to who they should trust that some kind of help is needed. A paper like this will have no effect at all on the workings of science itself; but it can do a lot of damage for the understanding of people who are not experts but who are keen to understand the issues. In my view, a lot of patience is required here. It's normal for keen amateur enthusiasts, such as most of us here, to make lots of errors in something like thermodynamics. Here's a real scientific paper making a lot of claims. Many readers are bound to be unsure of who to trust, and that's normal. It doesn't mean they are bad people.

I also am going to benefit from a technical discussion on errors in this paper, because I also am not an expert. I know enough to identify some of the errors on my own behalf; but sometimes it takes me a while and I may trip up on details or miss some aspect of the argument that a real expert could see more quickly.

One thing I want to emphasize. This is not about global warming. It's simply about the physics of why the Earth is, on average, so much warmer than an airless moon right now.

The only reason this paper is getting much exposure is because it is feeding into a widespread public skepticism on global warming. But the questions raised in the paper are all about the physical thermodynamics of a fixed composition atmosphere, and it seeks to refute the conventional scientific understanding of why the Earth is, on average, so much warmer than an airless moon. It's not about changes to the composition of the atmosphere.

If there are readers out there who think that the atmospheric greenhouse effect as conventionally understood is wrong, then it would be instructive for them to propose an alternative. The amount of energy radiated into space from the Earth is the same as if the Earth was a uniform blackbody radiating at -18C. Yet the average surface temperature is much more than this. Why?

Cheers -- Sylas

 

[jostpuur]

I have been under an impression, that the claim of this paper would not be even "mainstream of the climate skepticism". For example I cannot believe that Lubos Motl would be repeating the claim that the greenhouse effect violates the second law of thermodynamics. But after getting curious, I started looking around in the internet...

Here's a website with a name Climate Research News. It has articles with names

"Variability of the West Antarctic Ice Sheet Over the Past 5 Million Years"

"New Peer Reviewed Study: ‘Falsification of the Atmospheric CO2 Greenhouse Effects Within the Frame of Physics’ by Gerlich & Tscheuschner"

"New Paper Demonstrates Anthropogenic Contribution to Global Warming Overestimated, Solar Contribution Underestimated"

"More Evidence of a Warm Bias in the Surface Temperature Record"

...

Very typical climate skeptical stuff, and this paper by Gerlich & Tscheuschner is among the rest just like nothing special.

A blog with a name Greenie Watch. The blogger starts talking as if the paper by Gerlich & Tscheuschner is obviously true, and then keeps on telling how the alarmists don't even know what the second law of thermodynamics is. He explains that he has attempted to debate with alarmists about this, but the alarmists are not interested answering to him, because the alarmists feel insecure with such advanced topics in physics.

What is this http://canadafreepress.com/ supposed to be? Looks like a news website. It has this article. The article starts with this:

It is my sincere wish that climate alarmism has finally hit the buffers with the definitive and scientific deathknell administered by two German physicists, Dr. Gerhard Gerlich, of the Institute of Mathematical Physics at the Technical University Carolo-Wilhelmina in Braunschweig and Dr. Ralf D. Tscheuschner, co-author of a July 7, 2007 paper titled “Falsification of the Atmospheric CO2 Greenhouse Effects Within the Frame of Physics”.

Here's another website with a news website appearance: http://archive.newsmax.com/archives/articles/2007/8/6/104929.shtml It has an article which starts like this:

Global warming fanatics insist that "the science is settled" regarding this contentious issue and they're right — two German scientist have settled it once and for all by proving conclusively that there is no such thing as a "greenhouse effect" in global climate.

WOW! These skeptic guys are taking this all seriously! This is... well... "alarming".

I have usually thought that the skeptics' hypothesis, that the grant policies have affected the research results, sounds theoretically possible, and therefore it would be smarter for me to stay quiet and look what happens when "big guys" debate. But seeing the skeptics taking this second law of thermodynamics controversy so seriously is very eye opening.

Any comments?

I think that these guys carried out some "self-Sokaling". I mean that if some climate scientists wanted do some testing on the integrity of climate skeptics, they could try to publish this kind of paper as a Sokal trick. It seems that there is no need for this, because the skeptics Sokal themselves spontaneously.

 

[jostpuur]

Of course the remark that there are lot of skeptics who have poor understanding on physics does not logically imply that all skeptics are like that. Anyway, IMO my previous post gives some perspective to this thing.

 

[adb]

This IPCC greenhouse diagram is good news for sunbathers :
http://www.climateprediction.net/images/sci_images/ipcc_fig1-2.gif

... it shows twice as much radiant heat reaching us from the atmosphere as from the sun !

Even when the sun goes behind a cloud, you can still get twice as much heat being radiated from the sky as from the sun.

 

[Xnn]

Skin is tanned from exposure to ultraviolet radiation. The back radiation in the IPCC diagram is infrared radiation (longer wavelength). So, there is little tanning effect to the skin.

However, sunbathers generally appreciate warm weather and for that they should be very grateful of the warming effect of greenhouse gases!

 

[Borek]

No to mention the fact, that without atmosphere they will get fried, not tanned. But that's not a greenhouse effect. Quite the opposite.

 

[adb]

However, sunbathers generally appreciate warm weather and for that they should be very grateful of the warming effect of greenhouse gases!

To be more precise, sunbathers should be grateful to the IPCC for inventing a fictitious way to stay warm without the sun ...

... but then again, the IPCC and its railway engineer chief, invent all sorts of nonsense to support their political propaganda.

 

[sylas]

This IPCC greenhouse diagram is good news for sunbathers :
http://www.climateprediction.net/images/sci_images/ipcc_fig1-2.gif

... it shows twice as much radiant heat reaching us from the atmosphere as from the sun !

Even when the sun goes behind a cloud, you can still get twice as much heat being radiated from the sky as from the sun.

You need to bear in mind that the diagram is giving numbers that are averaged over the whole planet, including night and day, tropics and poles, under cloud and under clear sky.

The diagram gives you a pretty good idea of what you get if you are out on the beach for 24 hours, in spring or in autumn, somewhere in mid-latitudes, with a bit of cloud. Sure enough, in this case the backradiation from the sky -- which was predicted by basic physics and confirmed by direct measurement more than 50 years ago -- will be giving you more radiant energy than the sun, in total.

But you can still use the numbers in the diagram to make credible conclusions about a day at the beach, by applying some straightforward physics and geometry. For a sunbather, they are most likely to be in the tropics or subtropics, near the middle of the day. There's probably little to no cloud, if you are sunbathing.

Now the solar input given in that diagram is divided by four, which is the ratio of surface area between a sphere and a circle. This factor is correctly used in the G&T paper as well, when they find the average solar input for a globe.

Your sunbather, if they are foolish enough to be in the tropics with the Sun right at the zenith, will, on average, be getting four times more solar input than what is given in the diagram. Furthermore, this is still an average between clear and overcast days. If they pick an especially clear day, it will be somewhat greater again, since the reflection and absorption of the atmosphere will be less than the average.

The diagram shows 198 W/m² coming down to the surface. (Of which 30 is reflected and 168 is absorbed). You should expect, therefore, roughly 800 W/m² as an average for a tropical midday Sun. It will be less when cloudy and more when clear. The measured values do indeed maximize around 1000 W/m². You can also get up to such values in midsummer in temperate latitudes, as long as the Sun gets close to directly overhead and the sky is clear.

What about backradiation? Well, this does not actually change a great deal between night and day. There is a bit of difference, but because the atmosphere is able to retain some heat, the 12 hours of night is not enough for it to cool enormously by radiation. Even more importantly, the atmosphere is heated from the surface, not the sky. At the beach, the surface is mostly water, which has a huge heat capacity. As well as this, the atmosphere is fluid, and there is plenty of mixing. All of this means that the atmosphere remains at roughly the same temperature. This too, is confirmed by direct measurement of the backradiation, which I cited for you earlier. So the number in the diagram is about right for the backradiation, at about 324.

Finally, you do also get radiant energy up from the surface. This averages around 390 W/m². Now this is the radiant energy from a blackbody at temperature 15C, which is indeed about the average surface temperature. So at midday, on a warm day at around 30 to 35C, you can reasonably expect this to come up to blackbody radiation of about 480 W/m² or so. The atmosphere will scale up as well, but by a smaller factor, because it is being heated from the surface and will be damped. So the backradiation will be more than 324, but by a comparatively smaller amount than the increase at the surface.

So, in summary. You can conclude from the data in that diagram and a bit of basic geometry and thermo, that your sunbather will be getting most of their radiant energy from the sun. They will also have quite a lot of heat coming up from the surface, and a little bit less again from the atmosphere.

If I may suggest gently… don't just make fun of this. I'm trying to help. This is not merely theory, but basic data. You can go out and measure radiant heat, and it does indeed give values consistent with that diagram. The physics of how the atmosphere helps keep our planet a comfortable temperature has been known for a over a century, and the attempt by Gerlich and Tscheuschner to "falsify" such basic thermodynamics is simply pseudoscience… not because the conclusions are prohibited, but because their actual argument is seen on examination to be riddled with very basic errors, at a level that should be identifiable for an undergraduate level student of thermodynamics; or at least recognized when the errors are pointed out.

Cheers -- Sylas

PS. It was in another thread that I gave the citation for a direct measurement of atmospheric backradiation, made in 1954. See [post=2128781]msg #73[/post] of "What's wrong with a bit of global warming?". The underlying physics of atmospheric thermodynamics is not from the IPCC; it is merely basic background needed for any scientific look at the causes of climate; and the numbers are checked by measurement. All this is done, and described, more than 50 years ago, and modern measurements continue to see the same thing.

The measured and predicted backradiation is described in Stern, S.C., and F. Schwartzmann, 1954: An Infrared Detector For Measurement Of The Back Radiation From The Sky. J. Atmos. Sci., 11, 121–129. (online). Measurements are given in cal/cm²/min, which can be converted to W/m² by multiplying by 697. Measured values converted to W/m² in the daytime ranged from 314 to 405; and at night from 206 to 312. That's right in the ballpark for the 324 planetary average quoted in the diagram.​

 

[Borek]

don't just make fun of this

Just to let you know - I have read your posts and explanations with huge interest. It is probably more stupid to deny greenhouse effect existence than to exagerrate its influence on the surface temperature. The latter means messing with fine details of complicated equilibria, the former - ingoring basic physics and obvious facts.