More circular logic from the Science Deniers

I submitted my simple explanation as to why Earth's average surface temperature is what it is* over on hard-core pseudo-scientific Alarmist website Science of Doom.
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* Skip to next dashed line if you are familiar with this explanation, but here's the crash course:

A planet will settle at a temperature so that it is emitting as much LW radiation to space as it gets in SW radiation from its sun. On earth, only the cloud tops and the cloud free sea/land can directly absorb solar radiation coming IN (this is an agreed amount, 240 W/m2 average), and the self-same cloud tops and the cloud free sea/land surface have to emit the same amount of IR radiation directly OUT to space. Cloud tops and sea/land HAVE TO settle at the temperatures they are to maintain this balance.

There is a separate closed cycle that operates between clouds and the sea/land below them, which can be ignored when we look at LW going to space (yellow box in my third diagram in the first link). However this closed cycle works (it's heinously complicated), it will always be overridden by the fact that the temperature difference between sea/land and cloud tops is dictated by the lapse rate, which in turn is dictated by gravity; the specific heat capacity of the atmosphere; and the impact of the latent heat of evaporation (plus/minus a few other bits, like geo-thermal or electrical energy).

Imagine the lapse rate like the surface of a still reservoir. The water surface will be level. If you pump water from one end to another, it will not change the 'flatness'; the water will just sink back in the opposite direction and end up level again. Similarly, the atmosphere can 'pump' as much radiation energy down as it likes (cooling things higher up and warming the sea/land); an equal and opposite amount of energy will flow back up again to reinstate the fixed and known lapse rate (cooling the sea/land and warming things higher up).

Maybe the sea/land warms up the air above it by conduction/convection, which in turn warms the air above that, all the way up? Maybe there's more evaporation from the sea/land? Maybe the sea/land just reflect the radiation back up? Overall effect as measured by thermometers = net nothing.

And surely, it is only absolute temperatures that we care about, not the precise mechanism of how it happens?
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On with the story.

The comments and replies are difficult to follow because of nesting of replies-to-replies and because they simply deleted some of my replies. They started off by just calling me a Climate Denier etc, but one commenter, Frank, humoured me. His first attempt was "Why do you assume that cloud emissivity is 0.7? The Climate Models assume 0.95 or 1.0?" I just looked this up from sources dating back to the 1970s, when scientists wanted to find out stuff with being prejudiced as to the answer. I put him straight with half a dozen references and his last response is this:

Mark: There are two energy balances you need to deal with: the energy balance across the TOA and the energy balance at the surface. The [Kiehl and Trembert] energy budget has both. The existence of DLR is only important to the surface energy balance. You can only “prove” DLR doesn’t exist or transfer heat to the surface by studying the energy balance AT THE SURFACE.

I never said that there wasn't any downwards longwave radiation. I just said that you can ignore it when estimating likely temperatures - see my level reservoir example.

Energy balance across the TOA is the simplest because you only need to deal with radiation, which in principle can be calculated given the known temperature and composition of the atmosphere.

This seems to be his tacit admission that my simple calculation is in fact correct.

Calculating the energy balance at the surface is more complicated, because you need to add convection of latent and simple heat and DLR to the energy fluxes arriving at the surface. You completely ignore latent and sensible heat, and therefore CAN’T DRAW ANY CONCLUSIONS ABOUT DLR!

'Energy balance' is in fact very easy because you don't need to worry about what type of energy it is. You can work out from sea/land upwards, layer by layer, how much total energy each layer has - mainly thermal energy (warmth), with significant amounts of potential energy (gravitational energy - which goes up with increasing altitude/falling temperature) and latent heat (which is highest immediately above the oceans and tails off as you go up when gaseous water vapour releases that energy again by condensing).

And you find that the total energy at all altitudes in the troposphere is exactly the same, which is what you'd expect, it's like entropy. Radiation is just one of many mechanisms that works towards that balance, making sure that the lapse rate is maintained, radiation energy itself is not conserved or stored and does not show up in the overall balance (don't confuse stocks with flows!).

(NB This energy balance does not hold in the stratosphere, where the sunshine warms things from above when ozone absorbs it (converts it to thermal energy), so total energy goes up with increasing altitude - up to the point where the air is too thin and there is no measurable ozone. The same as oceans, which are warmed by sunlight from the top down. Water is not a gas, so there is no lapse rate. Again, red herrings.)

So... he believes in some magically self-reinforcing one-way energy transfer system and ignores all the other effects that cancel it all out again. it's like believing in the sloping water surface on a reservoir -and that once you have got a slope, it will become ever steeper of its own accord and you can turn off the pumps. Sorry, not good enough and it's obviously nonsense. It's an answer desperately looking for a question.

Onwards, ever onwards!

"Refraction of Light through Rectangular Glass Slab and Glass Prism"

Here is a great explanation of how to work out what comes out of the other side of the slab/prism. I'm sure he'd get top marks in an exam, and on the basis of 'what goes in and what comes out' we know the result is correct.

But what nobody can explain - a proper physics prof. explains the head scratching in this video - are the striking differences, which appear to be down to weird quantum stuff and the wave/particle duality. And he's just talking about light travelling more slowly through a pane, he doesn't mention prisms (I don't think).

The different behaviour through a pane vs through a prism struck me a couple of days ago. The unanswered questions are:

1. UPDATE. Following Mark In Mayenne's comment, I rethought this one, there is no contradication here.

2. Why is light at all wavelengths bent in the same direction when it enters and leaves the pane (so barring reflections and imperfections in the glass, the image is the same on the other side), but is split by frequency when it enters and leaves the prism (so the image is quite different on the other side)?

3. What would an observer see if he were inside the pane/prism, looking towards the light source? At that stage, the light hasn't been bent again on leaving and the light doesn't 'know' if it's in a pane or in a prism? Would the light be split by frequency or not?

4. With a pane of glass, you can assume that the light behaves as a wave. When waves in water reach shallower or deeper water, they change direction in predictable fashion (regardless of frequency - all light travels at the same speed). Does light behave as particles in a prism? Does that go some way towards explaining the differences?

5. It's a like the 'dog running from A to B via swimming a canal diagonally' problem in maths. The actual calculation is heinously complicated (simplified version here, and even that one stumped a lot of people), but somehow dogs seem to be able to do this calculation by instinct and choose the fastest route.

With a pane of glass, the light (which travels more slowly through glass) takes the route from source to end point along the route that takes the shortest possible time, almost as if it 'knows', or as if takes every single possible route and then 'chooses' the fastest. So does the light somehow already 'know' whether it's entered a pane or a prism as soon as it enters?

The joy of all this is that nobody seems to know and probably never will, least of all me. I guess that's quantum mechanics for you. Light is inanimate, it surely can't 'know' anything, can it..?

Something to think about when you're at a boring event or you can't get to sleep.

1. What percent of the atmosphere is water vapour? 2. The lapse rate and latent heat of evaporation

There are many sources that say it's on average 2 percent.

I had long assumed this was correct, it turns it out that it's complete rubbish, and it's actually about one-tenth of that.

Here is a good overview, which says:

... if all of the water in the atmosphere rained down at once, it would only cover the globe to a depth of 2.5 centimeters, about 1 inch.

This number seems to be widely accepted and seems very plausible, although some say as much as 1.5 inches.

The total mass of air pressing down on 1 m2 of Earth's surface is about ten tonnes, a 2.5cm deep x 1 m2 puddle = 25 litres = 25 kg of water. So that means about 0.25 per cent by mass, or about 4,000 ppm by number of molecules, about ten times as much as there is CO2.
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The lapse rate and latent heat of evaporation.

We know that the dry lapse rate should be about 10 degrees/km, that's easy, it's acceleration due to gravity ÷ specific heat capacity = 10 degrees/km. Energy is conserved, it just changes from one form to another; thermal energy is converted to potential energy when air rises and vice versa. But the observed lapse rate is only 6.5 degrees/km. So there are 3.5 degrees/km 'missing'. How does that tie in with the amount of water vapour, which holds 2,257 J/g of latent heat?.

I spent about two hours scribbling calculations to reconcile all this before I noticed that the original estimate is out by a factor of ten; after that it took five minutes. The answer is about 9 grams of water per m3 at sea level, falling by 1.5 grams per m3 per kilometre altitude up to 6 km altitude. The air is pretty dry above that (all water vapour has condensed out as clouds). Add them all up, and you get back to the total mass of about 2.5 kg in the lowest 6 km (average = 4.5g x 6,000m = 2.7 kg).

Entropy says the total amount of energy will spread out evenly. Using rounded figures...
1 m3 at sea level has:
- potential energy = 0 kJ
- 288K x 1,000 J/K/kg thermal energy = 288 kJ
- 9g water vapour x 2,257 J/g latent heat = 20 kJ
Total 308 kJ.
1 m3 at 1 km altitude has:
- 1 kg x 9.81 N/s2 x 1,000m = 10 kJ potential energy
- 281.5K x 1,000 J/K/kg thermal energy = 281 kJ
- 7.5g water vapour x 2,257 J/g latent heat = 17 kJ
Total = 308 kJ = the same as at sea level.

Reality check: 9 grams/m3 = 7g/kg of air = 65% relative humidity at 288K. That seems a bit high, but that is probably largely due to my crass rounding, approximations and the fact that sea level temps are between 'below freezing' and 'very warm' and RH is not linear with temperature. Above the Poles at minus 20C and 50% RH, there's only 0.6g/kg; over the tropical oceans at 30C and 75% RH, there's 20 g/kg. Or something like that.
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Then there's the thorny issue of splitting that 2.5kg into gaseous water vapour and tiny droplets in clouds (which have lost their latent heat). It turns out that the amount actually in clouds is only a few grams out of the 2.5 kg total, so can be ignored for these purposes.
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Which is all rather surprising really; of all the water on Earth, only about 1/10 of 1% of 1% is in the atmosphere, and only a small fraction of that is in clouds. Yet clouds they have a dramatic effect on the weather, and if you overlook them, your in/out radiation calculations will be wildly wrong. For some reason, AGW Theories rely on the wildly wrong calculations, but hey.

The long history of diagonal comparisons

Bayard in the comments linked to Eunice Newton Foote, the Forgotten Pioneer of the Greenhouse Effect:

In her brief study [in 1856], entitled Circumstances affecting the Heat of the Sun’s Rays, the amateur scientist described an experiment in which she exposed glass cylinders equipped with thermometers to the Sun and attached to a pump to draw air from one and compress it in the other.

Eunice compared the heating and cooling in the two cylinders. She observed, first, that the cylinder with the compressed air heated up more than the other in which the vacuum had been drawn. Second, that the heating was greater with moist air than with dry air.

Thirdly, and this was her great and almost fortuitous discovery—since she also experimented with hydrogen and oxygen—that the greatest degree of heating occurred when one of the cylinders was filled with carbonic acid gas: CO2.

OK, this experiment suggests that some gases warm up more than others when in bright sunlight. This illustrates quite a few interesting things about the properties of glass and various gases - mainly density and specific heat capacity of gases, which is why you get the same result with pure argon as with pure CO2 - but it does not in the slightest illustrate what they claim it illustrates. For clarity, Earth's atmosphere is approx. 1% argon and 0.04% CO2.

Here's an article which - inadvertently - makes the contradiction clear:

How can I see for myself that CO2 absorbs heat?

As an experiment that can be done in the home or the classroom, Smerdon recommends filling one soda bottle with CO2 (perhaps from a soda machine) and filling a second bottle with ambient air. “If you expose them both to a heat lamp, the CO2 bottle will warm up much more than the bottle with just ambient air,” he says.

Fine, it does just that. Now, what's the theory again?

Why does carbon dioxide let heat in, but not out?

Energy enters our atmosphere as visible light, whereas it tries to leave as infrared energy. In other words, “energy coming into our planet from the Sun arrives as one currency, and it leaves in another,” said Smerdon.

True.

CO2 molecules don’t really interact with sunlight’s wavelengths. Only after the Earth absorbs sunlight and reemits the energy as infrared waves can the CO2 and other greenhouse gases absorb the energy.

Woah! Just woah! The experiment shows that CO2 is warmed by SW radiation from the Sun (or heat lamp); then they say that CO2 isn't affected by SW radiation, it is only warmed up by LW radiation from the warmed surface ('traps heat')!

If they wanted to illustrate how CO2 is warmed by LW radiation from the surface (i.e. warmed more than N2, O2 or Ar), they should put their bottles - including one filled with argon as a control - in the shade, so that they are only affected by LW radiation from the surface. If the CO2 bottle reaches a higher temperature than the others, it would be persuasive. Only they know that this wouldn't happen and so would not support the theory... which is why they don't do it.

Science news.

1. From the BBC:

"Distant starlight gets stretched by the expansion of the Universe and shifts into the infrared region of the spectrum. We call it redshift," explains Richard Ellis, a University College London astronomer who's impatient to explore the end of the dark ages.

"The limiting factor we have with Hubble, for example... It's also not a particularly large telescope. It's been a pioneering facility, for sure. Amazing pictures. But the diameter of its mirror is only 2.4m, and the power of a telescope scales with the square of the diameter of the mirror. And that's where JWST comes in.

Why doesn't he just say "the power of a telescope scales with its surface area"? That's easy to understand and makes sense. He's trying to sound too clever for his own good.

2. Also from the BBC:

The UK is having the warmest New Year's Day on record, with new high temperatures set for the second day in a row, the Met Office says. St James's Park in central London saw temperatures of 16.3C (61.3F) on Saturday as 2022 was ushered in...

The previous New Year's Day record was set in [drumroll please...] 1916, when it reached 15.6C (60.1F) in Bude, Cornwall.

It would appear that average temperatures are going up slightly in many places, but the constant cherry picking is like the boy crying wolf, I believe it less all the time. 0.7 degrees per century doesn't strike me as too catastrophic. It would be just as easy to cherry-pick the other way and list all the places where New Year's Day was colder in 2022 than it was in some other random year like 1916.

Similarly, there have been a lot of forest and brush fires in recent years. If somewhere has a particularly big or damaging fire, then they are quick to shout about it as if it had never happened before.

But what about all the places which have had large fires in the past which didn't have any fires at all in recent years? Do they mention those? Nope. That's just what forests do - they burn down every few decades and then grow back - or else there wouldn't be any forests left. If we stopped chopping them down, there would be as many trees as there ever were.

Why are clouds at that particular altitude?

If you round up two-thirds cloud cover to 100% cloud cover and assume they have an albedo of 0.3, then the real reason for the apparent 33 degree Greenhouse Effect is immediately obvious, as I explained a month ago.

The next question to be answered is, why do clouds form so that the average altitude of their upper surface (the surface which absorbs and is warmed by solar radiation) is at about 5 km* (with a resulting sea level temperature of 288K)? Why not 4 km or 10 km? I've struggled with this for the past month, and, much head scratching, calculating, sketching and Bingling later, what it boils down to is as follows:

* Clearly, cloud cover is not 100% at 5 km and clouds don't have an alebdo of 0.3. Cloud cover is about two-thirds; their upper surface is higher than 5 km (call it 7 km); and clouds have an albedo of 0.4. But if you do a weighted average altitude and albedo of 'what the sunshine hits first' it's 5 km and 0.3.

1. The dew point of the water vapour in any 'parcel' of air depends on three variables. For a start let's focus on i. air temperature and ii. air density/pressure. We'll get back to variable iii. Relative Humidity later, You can merge ii. and iii. into one variable called 'partial water vapour pressure', but it's easier to treat them separately:

For a given R.H., in warm air, water vapour is likely to stay as a gas; in cold air it is more likely to condense and fall as rain. There's a narrow range of temperatures where it remains as tiny droplets which remain suspended in the air: 2. For a given R.H., if air has low pressure/density, the water vapour is more likely to remain as vapour. If it's high pressure/density, it is more likely to condense and fall as rain: 3. We can put those two together into a table of all possible temperature/pressure combinations.

Some vapour in the air will condense into tiny droplets, small enough to stay suspended and form clouds. Only those clouds which happen to form at the altitude where that particular temperature-pressure combination is in the white band will remain as clouds. So they could be low and warm or cold and high: 4. But the upper surfaces of clouds tend towards the same temperature because they absorb solar radiation. With an albedo of 0.3, they will reach an average temperature of 255K (average of day and night). So they mainly form at the altitude where the pressure/density is such that they fall into the white 'just right' band. Any higher, they will evaporate again, any lower and they will condense and fall as rain: 5. OK, so some clouds have formed at the 'right' altitude and are stable for now. We know the temperature of their upper surface, and that that temperature plus altitude x lapse rate (also known) determines sea level temperature.

But wouldn't this be positive feedback? Higher clouds = warmer surface = overall warmer atmosphere = atmosphere expands verrtically = higher clouds? For example, the whole tropsphere over the Equator and Tropics is twice as high as over the Poles, with a correspondingly higher 'right' cloud altitude.

What sets the upper limit..? 6. The upper limit is set by the third main factor for determining dew point - Relative Humidity. It is chaotic and dynamic but self-correcting. If the clouds are too high, so is sea level temperature, which leads to more evaporation, higher R.H. and higher R.H. means lower clouds again, and vice versa: 7. Some clouds will form at the 'Goldilocks' altitude where the resulting sea level temperature generates enough R.H. to maintain the clouds at that particular altitude. This is arrived at by trial and error, and while the precise calculations are beyond human comprehension, clouds do it for us by simply following basic laws of physics until they 'get it right': 8. Finally, you end up with what you expect to see. Sea level temperature 288K; clear air up to a certain altitude (too warm for clouds to form); a layer of clouds 1 or 2 km thick (the 'Goldilocks altitude'); above that clear air again (the pressure/density is so low that clouds evaporate again). Clearly, this is weather, so these are not exact values. They are all constantly overshooting in both directions, but it all oscillates around some sort of equilibrium and averages out. 9. What other evidence to we have to support this, apart from it matching up to observations and being entirely consistent with basic physics and everything else in the overall theory?

a. All I can think of for now is that areas with higher R.H. tend to have lower clouds (as you would expect. If there's more water vapour it's more likely to condense at a lower altitude) and their sea level temperature tends to be a bit lower (lower cloud altitude means the difference in temperature between upper surface of clouds and sea level is lower, as there are fewer km to multiply by lapse rate) than in drier areas.

b. Higher R.H. and lower clouds also mean a much smaller day-night ('diurnal') temperature range - water vapour is good at holding on to thermal energy and the lower clouds are good at reflecting upwelling IR back down to sea level in the night time. This is also observed in real life.

c. Venus and Mars follow exactly the same pattern, even though their atmospheres are nearly 100% CO2 and other 'greenhouse gases'.

An inconvenient truth

I have spent the last year and a half reading up on AGW theory. One after another, I have managed to iron out most of the contradictions, half-truths and flawed explanations for correct observations. Each one is a bit of an intellectual effort to overcome because it's all things that most people - Alarmists, sceptics, weather forecasters and the man in the street (i.e. me) - just take for granted.

I have spent most of that year and a half kicking myself for being sent off in the wrong direction for not having noticed something sooner, going back, rethinking and redoing my workings (and regretting many of my posts based on false - but widely held - assumptions). I hope that I have now got the bottom of it all and overcome the final false assumption, which had been nagging me for months...
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The 'inconvenient truth' is that the entire Greenhouse Effect is due to clouds (and their altitude)!

All the Alarmist pictures and diagrams just show the sunlight hitting the surface and being reflected back down by Greenhouse Gases. Clouds - when they appear at all - merely serve to reflect even more radiation back down and 'warm' (i.e. slow down the cooling of) the surface (which they clearly do during the night time).

To get back to reality, you have to draw in the cloud cover (accepted as two-thirds of the surface, so we might as well round that up to 'all of it') on all their pictures and diagrams and realise that most sunlight hits clouds first - that is the layer that absorbs sunlight. The temperature of their upper surface is determined by sunlight, and that in turn dictates the temperature of land and oceans via the gravito-thermal effect (the Greenhouse Effect = cloud altitude x lapse rate).

When you draw in the missing clouds, you realise what's causing the 'back radiation' and what's blocking terrestrial radiation from all getting to space and being measured by satellites. They are big white things that can be miles thick. They reflect sunlight, so we have to assume they reflect all EM radiation to the same extent (arguably more). It appears to be widely accepted that higher clouds mean a warmer surface than lower clouds, this is a correct observation and ties in with all this.

Another smoking gun is that on Venus and Earth, the upper surface of clouds is at the 'average emitting altitude' aka 'effective radiating layer'. This is not a coincidence - to all intents and purposes, they are the 'effective radiating layer'.

Clouds are also the 'effective absorbing layer' as far as incoming sunlight is concerned. Remember that they calculate a planet's 'effective temperature' based on 'what the sunlight hits first'. The 'effective temperature' calculation gives reliable answers, and so unsurprisingly, a planet's 'effective temperature' is pretty much the same as the actual temperature of what the sunlight hits first - namely the upper layer of clouds.

Unless a planet or satellite has no clouds (Mars, Moon) in which case the 'effective temperature' is a good approximation of the actual surface temperature. (The maths is trickier with the Moon because it revolves so slowly.)
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To sum up - there is a Greenhouse Effect warming the surface. Clouds (if high enough) mean that the surface is warmer than it otherwise would be. Nothing to do with Greenhouse Gases.

"What?" shouts the audience, "Have you gone completely, stark staring mad?
A. Don't most people say that clouds have a small overall cooling effect?
B. Doesn't it get a bit cooler when clouds pass between you and the sun?"

A. Maybe they do, but it's not true. They don't. Do the interplanetary comparison:

Venus - completely covered with very thick clouds at a very high altitude (50 km to 80 km). Hard surface gets very little sunlight, and only indirect sunlight at that. Huge Greenhouse Effect, about 500 degrees.

Mars/Moon - no clouds. Hard surface gets all the sunlight you'd expect. No Greenhouse Effect - even though the Martian atmosphere has about thirty times as much CO2 as Earth.

Earth - two-thirds moderately thick cloud cover at a few km altitude. Moderate Greenhouse Effect, accepted as 33 degrees.

Conclusion - the higher and thicker the clouds, the larger the Greenhouse Effect.

Caveat - clouds have a higher albedo (reflect more sunlight) than land or oceans, so they have to be at a certain minimum altitude for there to be net warming (so that the lapse rate effect trumps the missing sunlight). When I say 'net warming' I am comparing a hypothetical planet with and without clouds - NOT a cloudy and cloud-free area on the same planet. That minimum altitude is two-to-three km above the Earth's surface as far as I can make out, and on the whole they are much higher than that.

B. Yes, but you have to compare like-with-like.

i. Higher clouds warm the atmosphere, but it is not a local effect. The atmosphere tries to equalize temperatures around the globe (a phenomenon we refer to as 'the weather') and does a fairly good job under difficult circumstances (freezing poles, sweltering deserts). The oceans do the same thing, but that is way more complicated and poorly understood.

ii. Most of the temperature you feel - and all of the official temperature measurements - is the air temperature with no direct sunlight. Direct sunshine just gives a bit of a boost - on a hot, sunny day, it's still very warm in the shade with no direct sunlight. On a freezing cold winter day, it's still very cold even when standing in full-on direct sunlight hitting you at 90 degrees.

iii. So if you want maximum daytime temperature, you have to be a cloud-NIMBY - clouds everywhere else to warm the air (benefitting you as well as 'them'), but clear sky where you are to get the extra few degrees caused by the direct sunshine (only benefitting you and your immmediate neighbours).

iv. How many hours direct sunshine does a typical patch of land or ocean get in 24 hours? About four? Are those few hours really enough to keep the surface warm for the other twenty? Clearly not.

v. While you do feel warmer when there are no clouds between you and the sun, nearly everybody accepts that clouds tend to slow down cooling in the night time. The net effect is an overall win for clouds.

vi. If there are very low clouds (fog or mist) of course they have a direct cooling effect. That has partly to do with them blocking sunlight, partly with them being at a low altitude, but primarily because they make things damp and so the surface (and you) lose thermal energy because of the latent heat of evaporation.

vii. It is also the case that clouds often mean rain. We notice that rain cools the surface but we don't notice that this indirectly warms the atmosphere higher up - it's because of the latent heat of evaporation. So we automatically associate 'clouds' with 'cooler', not realising that most are 'high and dry'. There are clouds directly above you two-thirds of the time, but it's not raining two-thirds of the time, even in Wales or Norway.
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There. I've said it. Sue me.
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The icing on the cake is that some Alarmists say that warmer temperatures will evaporate the clouds = more direct sunlight on the surface = higher temperatures. The opposite is true! Less cloud cover would mean a) less Greenhouse Effect and b) more direct radiation from surface to space, especially at night = lower temperatures again, so entirely self-regulating = stable temperatures.

"Let's just ignore the most important thing, as that would blow all our theories out of the water."

From Pseudoscience of Doom:

We are still looking at how radiation travels and interacts with the atmosphere before anything changes.

There is a lot of fascination in the subject of the “average height of emission” of terrestrial radiation to space. If we take a very simple view, as the atmosphere gets more opaque to radiation (with more “greenhouse” gases) the emission to space must take place from a higher altitude. And higher altitudes are colder, so the magnitude of radiation emitted will be a lesser value. And so the earth emits less radiation and so warms up.

This “average height of emission” is often supplied as a mental model and it’s a good initial starting point.

Here is the result of the atmospheric model created with a surface temperature of 288K (15°C), 80% humidity in the boundary layer and 40% humidity above that (the “free troposphere).

This is a cloud-free sample – clouds are very common, but really make life complicated and we are trying to provide a small level of enlightenment. Simple stuff first.

There follows a tortuous series of calculations based on certain arbitrary assumptions which inevitably prove their point.
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Q. Why do they always ignore clouds, which cover average two-thirds of the Earth at any one time? They are more than "very common". They are the norm.

A. It is because clouds actually explain pretty much the whole of the so-called 'greenhouse effect'...

1. The "average height of emission" concept is actually very useful in mathematical terms, although they are applying it to the wrong thing and in the wrong direction.

2. If we are going to simplify things, it makes more sense to round up that 'two-thirds of the surface' to 'all of the surface' instead of rounding it down to zero. The upper surface of clouds is on average 5 km above the surface. Earth and its clouds have an average albedo of 0.3, so let's assume these clouds have an albedo of 0.3.

3. As far as incoming solar radiation and 'effective temperature' are concerned, the 'effective surface' is the upper surface of clouds. When you calculate the 'effective temperature' you are in fact calculating/estimating the temperature of the upper surface of clouds. Unsurprisingly, a planet's 'effective temperature' is, in real life, very close to the actual observed temperature of the upper surface of clouds. Except on Mars, where there aren't any clouds, so the 'effective surface' and the hard surface are the same thing.

4. The temperature at the hard surface (land or ocean) is simply the temperature of the upper surface of clouds, plus their altitude x the lapse rate (the 'gravito-thermal effect' which is dictated by basic maths, GCSE level physics and a bit of common sense).

5. The simple approach from 4. neatly explains the hard surface temperature of...
a) Venus. 'Effective temp' and actual temperature of upper surface of clouds = 232K. Upper surface of clouds altitude (call it) 63 km. Lapse rate 7.9 K/km. Hard surface temperature = 232 + (63 x 7.9) = 733K.
b) Earth. 'Effective' and actual temperature of upper surface of clouds = 255K. Upper surface of clouds altitude = 5 km. Lapse rate 6.5 km. Hard surface temperature = 255 + (5 x 6.5) = 288K.
c) Mars. 'Effective' and actual temperature of hard surface (no clouds) approx. 215 K, no 'greenhouse effect'. Even though there is about thirty times as much CO2 above every m2 of Mars than there is on Earth!

6. There's always the question of cause-and-effect. What seems more plausible:
a) The "average height of emission" dictated by 'greenhouse gases' and the clouds just happen to form with their upper surface at the same altitude? Or,
b) The clouds have their own rules, they form where they form, and their upper surface is, in practice, the "average height of emission", because they are the only surface that can emit radiation directly to space? Or indeed absorb radiation directly from space?

7. Then *drumroll* there's the 'trapped radiation' myth. The hard surface is 288K and emits, mathematically, 390 W/m2. Measured from space, Earth emits 240 W/m2. The myth is that one-third of radiation emitted from by the hard surface is 'trapped' by 'greenhouse gases'. Nope. When you measure from space, you are measuring the radiation emitted by the upper surface of clouds, which are colder and emit 240 W/m2, the same as what they absorb from the Sun.

(8. There is a completely separate system going on between the hard surface and the lower surface of clouds, it's the clouds that do the 'trapping', they get radiation from the hard surface, absorb some and reflect some back down again. Let's not go there for now.)

Clouds and climate lies

As we hopefully all know by now, the claim that Earth's temperature is higher than it 'should' be is based on sleight of hand - they use two quite distinct definitions of 'surface' and flip back and forth between them depending on what point they are trying to make.

Definition A is 'the surface you can see from space', which is largely the upper surface of clouds and some land/ocean that is not below clouds. Definition B is the land/ocean surface (ignoring clouds).

B is at a lower altitude than A, and hence B is warmer than A because of the gravito-thermal effect. The Alarmists pretend that A and B are inter-changeable, compare the expected temperature of A with the actual temperature of B and then say the reason is 'heat trapping gases'. They might as well blame it on The Seventh Curse of Zog; if you compare the expected and actual temperature of A, there isn't any definite difference and nothing needs to be explained.
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The problem with basing a theory on what is basically a Big Fat Lie is that you have to keep making up more lies to explain other phenomena.

From NASA's brainwashing for kids site:

So clouds can have both a cooling effect and a warming effect. When it comes to Earth’s climate, do clouds warm more than they cool, or is it the other way around? Well, that depends on where the clouds are in Earth’s atmosphere. [Actually, this is nonsense. The surprising conclusion is that clouds warm things up overall. But that's for a future post.]

Clouds within a mile or so of Earth’s surface tend to cool more than they warm. These low, thicker clouds mostly reflect the Sun’s heat. This cools Earth’s surface.

Clouds high up in the atmosphere have the opposite effect: They tend to warm Earth more than they cool. High, thin clouds trap some of the Sun’s heat. This warms Earth’s surface.
The observation that it's warmer under high clouds than under low clouds is broadly correct, but the explanation ("trapping the Sun's heat", FFS) is hokum. Two otherwise similar clouds (comparing 'low thick clouds' with 'high thin clouds' is another diagonal comparison) at different altitudes will reflect and absorb the same amount of sunlight and reflect and absorb the same amount of IR from Earth's surface, full stop. Or, comparing like-with-like, thin clouds reflect less sunlight than thick clouds but also reflect less IR from the land/oceans than thick clouds.

They also completely fudged the picture, the Sun is not 'a bit higher than the highest cloud' and can't sneak through the gap. To all intents and purposes, the Sun's rays are parallel. If you redraw the picture with parallel rays arriving directly from above, this would be obvious.

The correct explanation is far simpler and more coherent:

Clouds are primarily warmed by the sun from above!
There, easy. Once you accept that obvious statements, the rest follows.
* The temperature the clouds (are trying to) reach is the same, regardless of altitude (they are getting the same amount of sunlight).
* As a separate issue, the temperature below the clouds rises with decreasing altitude, at (say) 6.5 degrees per km (gravito-thermal effect).
* So the land/ocean surface below the high clouds is warmer.
* It's like two people who walk at the same speed, but one of them (the higher cloud) sets off earlier (higher up) and gets further (warmer) by a given end-time (the surface).
Here's a very simplified diagram to illustrate the point. 255K is the 'effective temperature' of Earth and its clouds - the sunlight hits the clouds first, so 255K is close to the actual temperature of clouds:
i. The effect is quite noticeable. We were on holiday in Yorkshire last weekend and there was more or less constant 100% cloud cover. When the clouds were high up, it was very warm down below; when they were lower, it was cooler. (As an aside, this explains the stupid high temperatures on the hard surface of Venus - their cloud cover is about 70 km up!)
ii. This also neatly explains why it's colder than 255K at higher altitudes. According to Alarmist theory everything must be at least that warm. The top of Everest gets sunshine, there's little cloud cover and there is still plenty of CO2 in the air above it. But it's colder than 255 K, not warmer. ----------------------------------------------
I realise that there is a lot more to all this; I am just addressing the narrow point about high clouds v low clouds.

AGW theory is based on two blatant 'diagonal comparisons' (Part 2)

In Part 1 I showed how they use a sneaky 'diagonal comparison' (i.e. they don't compare like-with-like) to create the illusion that Earth is warmer than it should be.  Part 1 covers the balance between Earth's system and the Sun/outer space.

Then there's what goes in within the Earth's system itself. The other sneaky thing they do is to say that the atmosphere is far warmer than it is, it's just a straight lie. From NASA's Earth Factsheet:

Terrestrial Atmosphere
Surface pressure: 1014 mb
Surface density: 1.217 kg/m3
Scale height: 8.5 km
Total mass of atmosphere: 5.1 x 1018 kg
Total mass of hydrosphere: 1.4 x 1021 kg
Average temperature: 288 K (15 C)

Say what?

Imagine you are asked to measure the average temperature of the water in a deep lake. If you just take the surface temperature, you might get ~288K. But that's not the average temperature of the all the water in the lake. By and large it gets colder as you go down, so the true average is much lower.

The reverse applies in the troposphere (the lowest ~11km of the atmosphere). This is the bit we are interested. It's where the weather happens and the layer which warms and cools the surface.

It gets cooler as you go up, so if you only measure the temperature in the warmest layer, at or slightly above sea-level (where most measuring stations are), you will get an artificially high average temperature (i.e. ~288K).

~288K is fair estimate of the average surface temperature, but that's something completely different to the average temperature of the air in the troposphere. That's a lot colder. If you take a fair sample of readings at all altitudes, you would get ~255K, which is not uncoincidentally the temperature we expect from looking at the Earth vs Sun/outer space balance. See also Climatologists are Flat Earthers.

The vertical temperature gradient is no mystery. Basic maths, a rudimentary understanding of the Gas Laws and common sense (principles and worked example) tell us that it must be warmer than the ~255K average at sea level and colder than the ~255K average at the top of the tropopause. They worked this out in the 19th century and it was part of normal physics textbooks until a few decades ago. There's a given amount of thermal energy, and gravity and the Gas Laws constantly recycle it downwards.

The precise temperature gradient (aka 'lapse rate') is primarily the trade off between thermal energy (temperature) and potential energy (altitude). We all know that warm air cools as it rises. Energy cannot be created or destroyed, so what happens to the 'lost' thermal energy? Easy - air loses thermal energy as it rises... and gains potential energy. The reverse happens with Chinook and Föhn winds (Föhn is German word, pronounced 'fern' and is also the name for a hand-held hair dryer), when falling air warms up. So the lapse rate = gravity ÷ the specific heat capacity of 'air'.

(The lapse rate is reduced by the latent heat of evaporation, which has the opposite effect. The surface is cooled when water evaporates, the latent heat manifests itself again higher up when water vapour condenses. The latent heat in one gram of water vapour is enough to warm a cubic metre of air by about 2 degrees, it's a lot.)
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The AGW theorists make great play of the fact that Earth's surface (being ~288K, not ~255K) radiates ~390 W/m2 but only ~240 W/m2 gets to space. They claim that the missing ~150 W/m2 is trapped by 'greenhouse gases'. This is part of Diagonal Comparison #1. Two-thirds of the surface doesn't radiate directly to space because it's covered by clouds; some of the surface radiation is reflected back down (in a quite literal sense, like clouds reflecting visible light) and the clouds themselves emit the required ~165 W/m2 to space. The average emitted to space ≈ 240 W/m2, which is what Earth receives from the Sun.

The AGW steamroller never stops of course. For sure clouds reflect some infrared radiation back down (which is why a cloudy night is warmer than a clear night), but clouds don't 'trap' radiation or warm the surface overall; on the whole, it's cooler if it's cloudy (there's no 'positive feedback'). And clouds certainly do not warm the atmosphere overall, the extra warmth under a cloud is equal and opposite to the missing warmth above it.

Radiation isn't pollution like plastic in the oceans, it can transform into other forms of energy instantaneously. Trying to account for it is like trying to catch sunshine in your hands. You cannot add, subtract, multiply 'radiations', the maths is insane but entirely unnecessary to explain and understand the basic equilibrium position with temperatures etc. You need to bring in radiation to reconcile the warming effect of Ozone Depletion, but that's another story...

AGW theory is based on two blatant 'diagonal comparisons' (Part 1)

The theory goes as follows:
1. Earth is 33 degrees warmer than it should be based in incoming solar radiation alone;
2. This is due to 'greenhouse gases' and 'trapped radiation';
3. Hence more greenhouse gases = higher temperatures.

Item 1. is based on the most outrageous Diagonal Comparison of all time. If this is not a valid comparison, then we need not concern ourselves with whether 2 and 3 are valid*.

The Hansen approach is:
1. Calculate the average effective (i.e. expected) temperature** of clouds, land and ocean surface. He just calculates one overall average temperature based on weighted average albedo (reflectiveness) of clouds, land and ocean surface, which is pretty close to the weighted average expected temperature of clouds, land and oceans separately. The key here is that land and ocean surface below clouds are ignored when calculating this expected temperature.
2. Compare that with the actual temperature of land and ocean surface... completely ignoring the actual lower temperatures of clouds.

A proper scientific comparison compares like with like!

So if you calculate the effective temperature of clouds, land and ocean surface (ignoring land and oceans below clouds), you have to compare it with the actual temperature of clouds, land and ocean surface (ignoring the land and ocean surface below clouds)... and you end up with a 'Greenhouse Effect' of +/- zero, zilch, nothing. Here are the numbers. (Cloud top altitude in pale blue as that is my best estimate and the variable most worthy of research or debate).

It all matches up nicely. Actual temperature ≈ expected temperature and outgoing infrared radiation ≈ incoming solar radiation. There is no 'missing radiation' or 'trapped radiation':
References:
Tutorial on the Greenhouse Effect, this explains how it is calculated.
How high in the sky are clouds?
Scientists detect world's coldest cloud hovering over Pacific Ocean
What is Earth’s surface emissivity?

* The real explanation for the apparent 33 degree difference is far simpler. The most plausible reason for the recent slight increase in temperatures is Ozone Depletion, but these have been crowded out. Whether you understand or agree with these is irrelevant to the question of whether there is any evidence for 'greenhouse gases' causing 33 degrees of warming in the first place.

** Effective Temperature is the hypothetical temperature that a planet would have to be to emit as much radiation as it receives from its star, assuming 100% emissivity. But it is a good first approximation for the actual temperature for a fast-spinning planning planet with a thick atmosphere, like Earth.
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The other Diagonal Comparison is that the official average surface temperature is NOT representative of average troposphere temperature, which is what we are interested in. Surface temperature measurements are 33 degrees warmer than the average temperature of the troposphere because measurements are weighted towards very low altitudes. This would not be so if Earth were covered with very high mountains. I'll cover that in Part 2, and then I'm done with this nonsense.

CO2 and the effective emitting altitude (2)

The 'top of atmosphere' theory of global warming is based on two actual facts:
a) The gravito-thermal effect exists (as adjusted for latent heat of evaporation/condensation), which is why temperatures fall by ~6.6 degrees/km as you go up through the troposphere (agreed).
b) Atmospheric density falls as you go up; so the amount of CO2 per cubic metre falls as you go up (agreed).

The theory says that a significant amount of radiation emitted below the 'effective emitting altitude' (at which CO2/m3 is a certain critical value) cannot escape to space; the 'thick' CO2 blocks it. Only as much radiation makes it past the 'effective emitting altitude' (above which CO2 is 'thin' enough to allow it through) as a planet receives from the sun, so they balance out and surface temperatures stabilise (all this is probably correct as well, by definition).

The theory also assumes that the temperature at the 'effective emitting altitude' is constant, which is circular logic. The 'effective emitting altitude' is just whatever altitude happens to be the same temperature as the planet's effective temperature, which in turn is only a ball-park estimate of actual surface temperatures. And radiation does not have a temperature anwyay - compare a 2,000 Watt electric fire with a 2,000 Watt radio transmitter. But hey.

THEREFORE, the theory concludes, IF overall CO2 levels increase, the effective emitting altitude goes up (you have to go higher up before CO2/m3 drops below the critical level) AND as a result of that, surface temperatures must go up - you are adding more km altitude x 6.6 degrees/km to a constant to work back down to the surface temperature.

The theory is intellectually appealing and it's difficult to prove or disprove the logic just using logic. All we can do is test the theory against 'real life'.

In the first test, we established that CO2/m3 at Earth's effective emitting altitude (~ 5km up) is ~0.5 g/m3. If the theory holds, the effective emitting altitude pre-1880 would have been ~3km up ≈2 km lower than now and surface temperatures would have been ~13 degrees lower than now. Surface temperatures (at the end of the Little Ice Age, natch) were only ~1.3 degrees lower than now, one-tenth of what the theory predicts, so the theory looks flawed to say the least.

I have given this some more thought and there's another way of testing the theory; we can apply the same logic to Venus, Earth and Mars and see if CO2/m3 levels at each planet's effective emitting altitude are similar. If they are, then that backs up the theory.

We find that the CO2/m3 level at the effective emitting altitude is ~3,500 g/m3 on Venus; ~0.5 g/m3 on Earth and ~18 g/m3 on Mars. The calculations are tortuous and took me all yesterday evening, so I won't bore you with them. The three planet's effective temperatures are quite similar (~230K, ~255K and ~205K) so I see no need to adjust for that. These CO2/m3 figures are so far out of line (whatever the margin of error in my workings) as to be meaningless.

So the theory fails this test even worse that it failed the first test. Having scored 10% on the first test (epic fail), it's not even trying to pass the second one. It's like handing in an essay about the Brontë Sisters at the end of a metalwork practical session.

Climatologists are Flat Earthers

Agreed facts:

1. If Earth had no atmosphere, then the average surface temperature would be about 255K (actually it would be higher because no atmosphere = no clouds = lower albedo = less sunlight reflected = more sunlight absorbed = warmer, but let's gloss over that bit). The turquoise is the surface, the sky appears black (like on our Moon): 2. Elevation or altitude would make no difference, the tops of mountains would be the same temperature as 'sea level' (like on our Moon):

3. We have an atmosphere, and because of the gravito-thermal effect, it is not 255K all the way up. It about 33 degrees warmer than that at sea level and 33 degrees cooler than that at the tropopause (the boundary between troposphere, warmed from below, and the stratosphere, warmed from above). The tropopause is on average about 11 km up, the altitude at which long distance airliners fly. Which is why mountain peaks more than half way up (Everest) are cooler than 255K at the top.

The Alarmists insist that the extra 33K at sea level is purely due to 'greenhouse gases' (some of them insist that the gravito-thermal effect can only exist if there are 'greenhouse gases' in the atmosphere), they are Flat Earthers and ignore everything to the right of the dotted line:

4. If Earth's surface were a lot more mountainous, covered in mountain peaks a lot higher than Everest which reached the tropopause, the overall average surface temperature would be about 255K, exactly the figure we would calculate from sunlight alone.

We would teach kids about the gravito-thermal effect to explain why mountain peaks are cold and valleys are warm, and the world would be a better place. Alarmists simply refuse to address this simple debunkation:
5. Of course, this does not explain small, shorter term fluctuations in temperatures, as we have seen over the past half-century*, but you can't just assume that a bit of CO2 = 33 degrees extra surface temperature and extrapolate from there. The Alarmists miserably fail to even try to explain how CO2 can cause warming at sea level but cooling on mountain peaks, even though mountain peaks get more sunshine than the surface, and although there is less CO2 above mountain peaks, there is still some.

* The most likely explanation, if this is indeed man-made, is ozone depletion caused by CFC gases. This is of serious concern. As it happens, this is also what might be causing cooling in the stratosphere. But I am well-versed in Alarmist pseudo-explanations - their take is that more CO2 in the stratosphere causes that cooling because it is at lower density and thus magically radiates more away from Earth than back towards it.

I suppose you could adapt this twisted-logic to explain the lower temperatures on mountain peaks and up where airliners fly, if you were capable of Double- and TrebleThink. The logical collorary of that would be that it would be warmer on mountain peaks if there were no CO2 in the atmosphere, or something completely mental.

Asimov in action

From Second Foundation (1948 to 1953):

Bail Channis sat at the control panel of the Lens and felt again the involuntary surge of near-worship at the contemplation of it. He was not a Foundation man and the interplay of forces at the twist of a knob or the breaking of a contact was not second nature to him.

Not that the Lens ought quite to bore even a Foundation man. Within its unbelievably compact body were enough electronic circuits to pinpoint accurately a hundred million* stars in exact relationship to each other. And if that were not a feat in itself, it was further capable of translating any portion of the Galactic Field along any of the three spatial axes or to rotate any portion of the Field about a centre...

The answer was of course spectographic analysis. For many centuries the main object of interstellar engineering was the analysis of the "light signature" of more and more stars in greater and greater detail. With this, and the growing precision of the "hop" itself, standard routes of travel through the Galaxy were adopted and interstellar travel became less of an art and more of a science

* The current best guess is that there are 150 - 250 billion stars in the Galaxy, maybe they didn't assume that seventy years ago? Elsewhere in the books is an explanation of a heads-up display, you just keep adjusting the virtual galaxy until it lines up against what you can actually see and hey presto, the computer tells you where you are.

From Sky News:

Prof Jorgensen had designed the four instruments that Juno used to track stars as part of its magnetometer investigation.

NASA explained that these onboard cameras took photographs of the sky every quarter of a second to determine Juno's orientation in space by recognising the patterns of the stars - an engineering task which was "essential" to the magnetometer's accuracy.

Which is the same general principle. I'm surprised that triangulation works on such a small scale (well within the solar system) because the parallax differences must be minuscule, but they seem to be able to make it work.

"Factoring in Gravitomagnetism Could Do Away With Dark Matter"

From SciTechDaily:

The main role of dark matter, Ludwig points out in the paper, has historically been to resolve the disparity between astrophysical observations and current theories of gravity. Put simply, if baryonic matter — the form of matter we see around us every day which is made up of protons, neutrons, and electrons — is the only form of matter, then there shouldn’t be enough gravitational force to prevent galaxies from flying apart.

By disregarding general relativistic corrections to Newtonian gravity arising from mass currents, and by neglecting these mass currents, Ludwig asserts these models also miss significant modifications to rotational curves — the orbital speeds of visible stars and gas plotted against their radial distance from their galaxy’s center.

This is because of an effect in general relativity not present in Newton’s theory of gravity — frame-dragging or the Lense Thirring effect. This effect arises when a massive rotating object like a star or black hole ‘drags’ the very fabric of spacetime along with it, in turn giving rise to a gravitomagnetic field.

That all seems very plausible to me. Well done, Ludwig, and let's shut down all these hugely expensive projects trying to identify or isolate Dark Matter, which will turn out to be the 21st century's equivalent of aether or caloric.

RE: ozone depletion - how does the extra Ultraviolet B radiation affect clouds?

That's a question to which I have found no obvious answer, but I assume that if there is a bit of extra high intensity UV-B hitting the atmosphere, it will evaporate some of the clouds, i.e. turn water droplets back into water vapour. The wavelength of UV-B is orders of magnitude less than that of infra red, so the chances of it being absorbed by a molecule in a tiny water droplet is commensurately higher. And 'absorbed' just means that radiation energy is converted to some other form of energy.

This can lead to a disproportionate effect on surface and atmospheric temperatures. This theory might be totally wrong of course but it seems plausible to me. The effect must be warming, however slight. I've not put numbers on the effect because you have to make far too many assumptions so that would 'prove' nothing. This is a wait and see operation. If I live long enough to see the 'ozone hole' repair itself (perhaps by the middle of this century?) and temperatures fall again even though CO2 levels have increased (and they will), then that would support the theory but not really 'prove' it either way:

1. Starting position pre-ozone depletion

Some sunlight hits the surface, most of it hits clouds and is partially reflected: 2. There is now more UV-B (imaginatively coloured violet, even though it is invisible)

Some hits the surface; most of it hits clouds: 3. Cloud cover is reduced

Some of the energy in UV-B evaporates water droplets and so is converted to latent heat of evaporation (no measurable temperature increase). That thins the clouds slightly and reduces the amount of cloud cover. This allows more sunlight at all other wavelengths through to the surface.

So it's not so much the bit of extra UV-B which warms the surface; it is all the other sunlight that isn't reflected and that now gets through. An average reduction in cloud cover of 2% reduces albedo and increases the amount of sunlight getting through by about 1%, sufficient to cause about 1 degree of surface warming: 4. At night, the water vapour condenses into clouds again

The energy converted to latent heat of evaporation during the day turns back into extra thermal energy when the water vapour condenses again (or the rate of cooling is lower than it otherwise would be). This warms the atmosphere slightly. The surface is also slightly warmer. The pink arrows denote the extra infra red and warmth generally:

"My confusion and anger ended when our host showed me the real physics"

I did a bit of light trolling at Science of Doom and elicited this response:

You are confusing several topics.

No I'm not. They are confusing the issue, as he later confirms:

Elsewhere I have discussed why it is simplest to consider the steady-state balance or imbalance at the TOA [top of atmosphere]. An imbalance at the TOA is created by rising GHGs slowing down the rate of radiative cooling to space. DLR is an internal radiation flux that moves heat WITHIN our climate system and therefore isn’t important to the radiative imbalance at the TOA. A “rising effective emitting layer" is important to the balance at the TOA.

Since AGW is a very complicated subject, it is often explained with a variety of models paradigms including: Increasing DLR “warms” the surface, CO2 “traps” heat, CO2 acts as a blanket or insulation, GHG’s act as shell or layer around the Earth (Willis promotes a “Steel Greenhouse” Model) and a “rising effective emitting layer” model (promoted here and by Linden among others). IMO – and others probably do disagree – all of these models are flawed.

Which was exactly my point. Notice how he first says that the "'effective emitting layer' is important" and then says that the "'rising effective emitting layer' model [is] flawed". I have spent a year wading through these endless layers of crap:

When I first came here (on the advice of Steve McIntyre), I was continuously frustrated and intemperate, because I KNEW that doubling CO2 would double the number of photons emitted by CO2 and usually halve the distance they traveled between emission and absorption. I couldn’t see why doubling CO2 would change anything – which turns out to be an excellent first approximation to the truth. The reduction in radiative cooling [to] space from 2XCO2 is barely more than a 1% change despite doubling the emission of photons by CO2. (As best I can tell, the rising effective emitting layer model doesn’t take into account the doubled emission of photons by doubled CO2.)

Luckily, Salvation is at hand for those Who Know And Want To Believe:

My confusion and anger ended when our host stopped talking about models and paradigms for AGW and showed me the real physics: Schwarzschild’s equation for radiation transfer. This is the equation that climate scientist use to predict that a doubling of CO2 will slow radiative cooling to space by about 3.5 W/m2. Unfortunately, this equation is a differential equation that must be numerically integrated over the path radiation takes, and therefore may or may not be meaningful to you...

I do not pretend to understand this equation numerically, but the gist of is what common sense would tell us: some gases are better 'insulators' against radiation than others, in the same way that some gases are better for thermal insulation than others, so radiation (or thermal energy) comes out of one side more slowly than went in on the other - but it still gets through in the end. Wow, big deal.
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Basic physics tells us that everything can radiate (we are told hat N2 and O2 can't, let's just accept that) and that the temperature of the atmosphere falls with increasing altitude (because of the gravity-induced lapse rate). Therefore, stuff which is higher up will be radiating less than the surface. Outgoing radiation is about one-third from the warmer surface and two-thirds from cooler clouds (which themselves have only about 75% emissivity) and if you average those out, you get the same answer as what is actually observed, which is what is needed to keep the atmosphere at a steady-state temperature.

PS, the figure of 3.5 W/m2 (which he himself dismisses as "barely more than a 1% change") is a key part of the Alarmist belief system. This was originally derived by simply assuming that warming over an arbitrarily chosen time period was directly caused by changes in CO2 levels. They later reverse engineered the answer they wanted from an equation not necessarily designed for this purpose. Even if correct, that equates to a surface temperature which is about 0.7 degrees warmer for every doubling of CO2. Again, big deal. (This is of course wholly at odds with Al Gore's claim that temperatures rise by about 1 degree for every 5% extra CO2, not that he ever retracted it or that the Alarmists even notice the discrepancy - if Al Gore's chart had been a good predictor, then temperatures would be about 10 degrees warmer than they actually are.)

"The Amazing Case of 'Back Radiation' – Part Three"

I dipped back into Science of Doom again for a giggle and ended up at this fine article, it's the third article in a series which is basically a long list of things which are undisputed. The series builds up to this:

Wavelength Dependence on the Temperature of the Source

Of course, radiation from different temperature sources do have significant differences – in aggregate. What most, or all, believers in the imaginary second law of thermodynamics haven’t appreciated is how similar different temperature Planck curves can be:
Notice the similarity between the 10°C and the -10°C radiation curves. Alert readers who have pieced together these basics will already be able to see why the imaginary second law is not the real second law. If a 0°C surface can absorb radiation from 10°C radiation, it must be able to absorb radiation from -10°C radiation. And yet this would violate the imaginary second law of thermodynamics...

Conclusion

[Downward longwave radiation] is emitted by the atmosphere, reaches the surface and is absorbed by the surface. This absorption of energy changes the surface temperature. The physics behind this are [sic] very basic and have been known for around 100 years. Proving that the surface doesn’t absorb DLR should be a walk in the park for anyone with a small amount of cash. But only if it’s true.

Say what now?

Let's assume the ground is zero degrees C. Case A: air from the south wafts in which is +10 C. We'd expect the ground to warm up a bit (and the air to cool a bit). Case B: air from Siberia wafts in which is -10C. A sane and rational person would expect the ground to cool further (and the air to be a bit less cold), but apparently, the ground will warm up almost as much as if the air were +10C rather than -10C. This would to energy appearing out of nowhere (because the air is also getting less cold) and so is clearly impossible.

And I'm not aware that the Second Law says that objects can't absorb radiation from cooler objects. That is a red herring and neither here nor there - if the warmer object is emitting more than it is absorbing, it is cooling down. What the 'Law' says, among many other things, is that heat goes from warm objects to cold objects. Whether that is due to conduction or radiation or anything else is a secondary issue. The word "radiation" only appears once in the very lengthy Wiki article (and once again in the footnotes). Rather conveniently for the forces of common sense and reason, it's in the following sentence:

The second law is concerned with the direction of natural processes. It asserts that a natural process runs only in one sense, and is not reversible. For example, when a path for conduction and radiation is made available, heat always flows spontaneously from a hotter to a colder body.

They seem to be trying to convince themselves of something that in their hearts they know is not true.
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The Alarmists sometimes use the warming effect of clouds, which is noticeable at night, as evidence to support this nonsense.

That is a different effect. The clouds are emitting their own 'colder' radiation (which has no effect), and also reflecting 'warmer' radiation emitted by the surface back to the surface (which does have an effect), at exactly the same 'warm' frequencies (colours don't change when reflected in a mirror) which the surface absorbs, reducing the net energy radiated away by the surface, thus warming it up (or at least, slows down the cooling process).

Even if you go with the Alarmist theory, if clouds reflect 60% of radiation at all frequencies, this makes it (say) 5 degrees warmer. CO2 can't re-emit downwards more than half of one-tenth of frequencies of radiation, so pro rata, that means about 0.42 degrees of warming and it can never be more than this, no matter how much CO2 there is.

Furthermore, if we are dabbling in crude radiation calculations, CO2 emits at 14 - 16 microns. Using Wien's Displacement Law, this is the peak radiation emitted by a blackbody which is only about 200K, i.e. about negative 70 degrees C. Which sure as heck can't warm the surface, that's just not happening.

Re: those experiments which purport to prove the Greenhouse Effect

Here's a typical example:

Can anybody see the 'glaring' error?

Agreed facts: the atmosphere is largely transparent to shortwave sunlight (wavelength less than 4 microns); the surface is warmed by shortwave sunlight; the surface emits longwave radiation (anything more than 4 microns).

Questionable claims: greenhouse gases reflect or reradiate 83% of this longwave back down to the surface; the surface receives twice as much 'back radiation' as it does actual sunlight (source). This is why the surface is 33 degrees higher than the 'effective temperature'. CO2 accounts for about one-fifth of this 'back radiation'*.

Does this experiment demonstrate back radiation or 'trapping'?

Nope.

What we see in this experiment is the two hot lamps warming up the two bottles and the gas in them. That's the 'glaring' error. The lamps are emitting lots of radiation at at wavelengths 14 - 16 microns, which CO2 absorbs (but N2 and O2 can't), warming up the CO2 (see bullet point 1 here). There is nothing magical about this; leave a piece of aluminium and a piece of wood in bright sunlight, the aluminium will reach a higher temperature.

A much fairer experiment would be to have three large greenhouse frames (the larger the better) covered in very thin, clear polythene (which allows most radiation through in both directions) in a shaded area, so that the only radiation they receive is longwave from the ground and from the surrounding atmosphere (which is much less intense than the light emitted by a hot lamp). UPDATE, it would be good idea to pipe water under the floor to keep it at the same temperature as nearby areas which receive sunlight /UPDATE. After all, the claim is that CO2 traps or absorbs longwave radiation emitted by the ground and the surrounding atmosphere. You have one full of normal air; one full of CO2; and one full of argon (monatomic and definitely not a greenhouse gas, as defined) as a control experiment.

CO2 and argon have a similar mass per unit volume and both have much lower specific heat capacity than normal air (see bullet point 5 of previous link); they also both have similar thermal conductivity, much lower than normal air (i.e. they are better insulators). Put your aluminium and wood in a freezer and the aluminium will cool down faster as it is a better conductor/worse insulator.

I'd be surprised if the greenhouse full of CO2 reached a steady state temperature (after a few days, averaged over a 24-hour period) higher than that of the greenhouse with normal air. That would be like putting our aluminium and wood in a larder and noticing a few days later that they are different temperatures. And even if it did, we have the argon-filled greenhouse as a control. The chances are, it would be a similar temperature to the one with CO2 i.e. most of the differences can be explained by their lower specific heat capacity (they warm up and cool down faster) and their lower thermal conductivity and higher mass per unit volume (they cool down more slowly).

To the extent that the 100% CO2 greenhouse is slightly warmer than the one with normal air, you adjust for its other properties by comparing it with the temperature in the 100% argon greenhouse (see previous paragraph) to arrive at a much smaller (and possibly negative) figure which will be the result of radiation 'trapping'. If it's negative, then stop right there.

If it's positive, let's be generous to the Alarmists and assume a logarithmic relationship between CO2 levels and temperature. You divide that extra temperature difference by 11.3 (going from 415 ppm to one million ppm is to double concentrations just over 11 times) to estimate the likely increase in temperature if CO2 levels were double their 'pre-industrial' level, i.e. 0.06% instead of 0.03%, and then  deduct the 1 degree that has already happened (we have already gone from 0.03% to 0.04%). Then - assuming we still have a positive number - count the zeroes after the decimal place! (If you assume a linear relationship - which is what the Alarmists' charts actually show - you'd divide the change by 2,500 and then subtract 1 degree). For completeness, normal air is 1% argon by volume, i.e. there's 2,500 times as much argon as there is CO2.
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Finally, I suppose you should repeat the experiment by setting up the greenhouses in the open, so that they also receive incoming sunlight during the day; that makes the downward adjustments more complicated because there will be a real greenhouse effect (no convection) but probably worth doing.
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* The precise fraction is never made clear, but clearly it's enough to make a difference if the explanation is correct.

While it is quite true that the atmosphere is radiating back at the surface and you can measure it, the atmosphere is cooler than the surface (because of the gravity induced lapse rate. If CO2 really 'trapped' warmth, the lapse rate would be higher than expected from first principles. Venus' atmosphere is 95% CO2 and the lapse rate is exactly what you'd expect from first principles) and the net transfer of heat (whether by radiation or conduction) will always be from warm to cool, but that's an aside, and even this basic truth is 'hotly' disputed by Alarmists, so let's concede on that to keep the peace. You can't just add radiation from different sources either, but hey.

Why the gravito-thermal explanation trumps the 'greenhouse effect'

UPDATE May 2021. I've boiled this all down to a simple explanation based on common sense, basic maths and a rudimentary knowledge of the Gas Laws.

Please read my post Acceleration ≈ Gravity
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From Forbes, replying to the question "If Heat Rises, Why Is It So Cold In The Mountains?":

Gas also get cooler as its pressure drops, which it does as it rises up where there is less air pressing down on it. So when warm air rises, it cools off. That’s pretty significant here.

This paragraph over-simplifies to the point of being totally wrong. The effect of reducing density by half and pressure by three-quarters (i.e. at 10 km up) would be to cool some air which has risen from the ground to about negative 100 C (if I understand this correctly). Actually it's a balmy negative 50 C up there.

What actually happens is sunlight hits the ground and warms it up; this warms the air; warmer air is less dense so it rises; energy cannot be created or destroyed, so thermal energy is converted to potential energy. That's how the lapse rate formula is derived, then you adjust it for latent heat of evaporation/condensation = 6.5 degrees per km altitude. You work out temperature first, and (lower) pressure and density are derived from that. Moving on...

But there’s an even more important force at work: Earth radiates heat (infrared light) into space. Down near sea level, heat from the sun hits the ground and is trapped under 100 km (at least) of insulating air and clouds that intercept escaping heat and re-radiate it back toward the ground. The higher up you go, however, the less any of this can happen. Above a certain level, the atmosphere loses heat to space faster than is can be warmed either directly (by sunlight) or indirectly (from the ground) so it gets colder and colder.

Up to a point.

Air, being mainly NO2 and O2 doesn't emit much radiation. Neither does CO2, for that matter, it just absorbs 5.14% of infra red and warms up slightly and then warms up the 2,499 other molecules around it (see footnote). The first assumption must that the atmosphere would warm to the same temperature as the surface. If you assume no atmosphere (like on the Moon), you can calculate the likely temperature of the surface quite easily and accurately, based purely on incoming sunlight = effective temperature +/- adjustments.

So our first assumption is that earth's atmosphere would be 255K (the effective temperature of Earth's surface based on incoming sunlight alone). And its average temperature is indeed about 255K, but then you have to adjust for the lapse rate, so it's 33 degrees warmer at the surface - and 33 degrees colder at the top of the troposphere, approx. 10 km up.

The final sentence ("Up to a point") is a nod to the fact that the greenhouse effect does NOT explain why it is so cold on very high mountains. If you look at the temperatures at the top of mountains which halfway up the troposphere (5km to 6km height), the temperature is what you'd expect based on incoming sunlight alone, you can cheerfully ignore all the air above it, of which there is still a heck of a lot (nearly half by mass). If the greenhouse effect existed, it would be warmer than that. No evidence of greenhouse effect.

But let's climb further, to the top of Mount Everest, near the top of the troposphere. Its effective and actual temperature would also be 255K (assuming no atmosphere) but its actual temperature is a darn sight colder than that. According to the greenhouse 'trapping' effect, its temperature would be at least 255K, plus a smidge for the greenhouse effect of the small amount of air above it (about 25% by mass). In actual fact, there appears to be a negative greenhouse effect. Which can't exist, by definition.
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Footnote - first the article says radiation energy is 'trapped' (plausible) and then they say it is re-radiated. Which one is it? It can't be both.

The Alarmists like to do demonstrations where they fill a tube with CO2, place a heat source at one end and measure the amount of radiation that gets through to the other end - it's very little, which indicates 'trapping'. If it were re-radiating, then at least half would get through. So 'trapping' seems more plausible and CO2 absorbs 5.14% of the radiation from the surface and warms up a smidge, that warms up the air around it by 1/2,500 of a smidge, which is a small number, certainly less than one degree. And the gravito-thermal effect greatly outweighs this at the top of Mount Everest.

Then there's this: "Above a certain level, the atmosphere loses heat to space faster than is can be warmed either directly (by sunlight) or indirectly (from the ground) so it gets colder and colder."

Nope. The atmosphere doesn't lose thermal energy to space (and it can't lose it faster than it receives it). The only way it could cool down is to emit radiation, which it doesn't (to any great extent). The point is, the air up there was never that warm in the first place - see explanation of lapse rate.