Whatever happened to back radiation? part II

Posted: November 16, 2010 by tallbloke in climate, Energy

A while ago I posted a tongue in cheek thread about the old Keihl and Trenberth Earth energy budget diagram and the new shiny all colour one NASA now has on their website. Here they are again for comparison:

The major difference between these diagrams is the ‘surface radiation’ from the surface to the atmosphere and the ‘back radiation’ from the atmosphere to the surface have been replaced by a ‘net radiation absorbed by the atmosphere’ figure of 15%.

The purpose of the original post was twofold. Firstly to convert the percentages in the new diagram into watts per square metre figures so we could compare the differences. Secondly to poke a bit of fun at Keihl and Trenberth, because their overly simplified diagram has been even more simplified by NASA, they have removed the seperate up-down surface and back radiation figures altogether.

Why might this be?

In a new post over at Science of Doom entitled Do Trenberth and Kiehl understand the First Law of Thermodynamics? Part Three the Creation of Energy? S.o.D posits a simple model and offers it as some kind of vindication of the Keihl Trenberth diagram. He states:

The reason this PVC sphere model appears so wrong to many people is for similar reasons that the famous Kiehl & Trenberth diagram seems wrong – the radiation “internally” (earth surface) is higher than the external radiation to space. (Note that the radiation values in the K&T diagram can be measured).

Note the bold type.

I think this is something of a trojan horse. I don’t have a problem with some of the internal surfaces in the climate system radiating at a higher rate than the Earth as a whole radiates to space, have a look down the crater of an active volcano if you don’t believe this is possible. What I do have a problem with is that S.o.D. seems to be trying to get us to accept the correctness of the whole of the Keihl Trenberth diagram and that one of the reasons we should accept it is that the radiation values can be measured.

I asked S.o.D to point me to some measurements of upward radiation from the ocean surface and a description of the hardware used. Here is his response:

As you can see in The Amazing Case of “Back Radiation” – Part One and Part Three the measurements of upward and downward longwave radiation at the surface are few and far between due to the expense of the instruments and the setup required.

However, sufficient measurements have been done to be confident that the Stefan-Boltzmann equation is correct and so if the SST is known accurately the emission of radiation is also known accurately.

Well excuse me S.o.D but divining the upward surface radiation of a surface which contains biological matter, roughness, and all manner of dispersed chemicals is not as simple as applying a law devised for theoretically pure and smooth ‘blackbody’ surfaces to a figure for temperature and cranking out a numerical result. Furthermore, since the primary energy path in the climate system is sun -> oceans -> atmosphere you might have thought some of the \$80billion spent on promoting the AGW theory might have been spared to do the job properly with empirical measurements. Unless of course those measurements might reveal something which runs counter to the theory? Maybe something that would show that John Nicol and G&T have a point or two?

I have asked for further clarification and repeated my request to be pointed to some, or even just one of these “few and far between” measurements. I’ll keep you updated. 🙂

[Update]

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19990100634_1999169386.pdf

“Recent measurements of spectral reflectances of surface
materials have clearly demonstrated that surface emissivities
deviate considerably from unity, both spectrally and
integrated over the broadband. Thus, assuming that a surface
errors
in surface temperature retrievals in longwave surface
energy budgets and in climate studies. ”

So S.o.D’s claim that the Stefan-Boltzmann equation for blackbody radiation plus surface temperature is sufficient to give an accurate surface longwave emission figure is falsified, along with Minnett and his skin temperature differential theory.

1. Giovanni Pellegrini says:

you might have thought some might bother to document himself before speaking.

http://gewex-srb.larc.nasa.gov/index.php

Best Regards

2. tallbloke says:

Hi Giovanni, and welcome.
You might have thought some might bother to check the methodology at the links they offer before speaking too. But thanks for the link, it is useful.

“NASA/GEWEX SRB Methodology

Below is a brief overview of the GEWEX Longwave and Shortwave Algorithms, and the Quality-Check Longwave and Shortwave Algorithms. A more detailed description of these algorithms is available in the Model Documentation. ”

As far as I can see, the ‘Model Documentation’ doesn’t deal with direct measurement of the longwave radiation from the ocean surface (the isssue I asked S.o.D about). It deals with an idealized model of the longwave radiation from the ocean surface.

Does the model include modifications to equations such as the Stefan – Boltzmann equation which are desiged to be applied to idealized smooth pure surfaces?

I think the answer is no, but maybe there is a valid argument that the fact that the ocean surface is not pure smooth water ‘doesn’t matter’?

I will read the quality assurance document linked at that methodology page to see if this issue is dealt with.

Click to access 19990100634_1999169386.pdf

3. But……what about the Sun?. It seems to be at the ER:

Better build nuke power plants before freezing…

4. tallbloke says:

More solar articles coming soon Adolfo. 🙂

5. Bryan says:

tallbloke

…..”Thus, assuming that a surface
errors in surface temperature retrievals in longwave surface
energy budgets and in climate studies. ”……..

I questioned SoD on this months ago(on his site) suggesting that using unity for emissivity and then claiming three figures of accuracy for radiation measurement (such as 396w/m2 for Earth surface) was scientific illiteracy.

Both Silas and SoD assured me that it was so close to unity that unity could be used.

The more I delve into so called “climate science” the more slapdash it appears.

Recently I read a textbook from a MIT professor and was startled to find;

(a) there is no perfect black body emitter so use gray body (e<1)

(b) there is no gray body emitter that has a reliable reduced black body spectrum.

What apparently is best pracice is to make a page for each material noting how it differes from the black body envelope and then recalibrate the measuring instruments.

Look at the problems encountered using this instrument.

http://www.pyrometer.com/Tech/emissivity.html

No wonder Trenberth has problems finding the "missing heat".

6. tallbloke says:

Bryan,
having read further through the NASA paper linked above, it turns out they have simply assigned the emissivity of clean lab water to the oceans. Soils and sands vary enourmously, depending on moisture etc, as much as 20% from black body emissivity.

All bets are off with Keihl and Trenberth, thats for sure.

They build up tables of adjustments from the variation at various wavelengths, and use those to adjust the satellite data. Whether the model are yet sophisticated enough to intgrate ranflall data to adjust for the varying emissivity of soils in various states of moisture I don’t know, but I doubt it.

I just want the climate establishment to own up to uncertainty levels so that they can’t get away with dismissing other factors any more.

7. gnomish says:

there is no missing heat
there are only inaccurate, incomplete and outright defective models
it’s ancient adolescents with a super-playstation playing World of Weathercraft at our expense.

it’s past the expiration date for this – fire the lot!
if that’s not possible – stop paying taxes.
one can be innocent, thereby, and have license to complain with no trace of hypocrisy.
people who do this to themselves are paying a high price for the luxury of pointless drama.

one gets what one pays for sometimes and what one settles for the rest of the time.
got pride?

8. tallbloke says:

I suspect the ‘missing heat’ already left the building through a window which was open substantially wider than Keihl and Trenberth thought it was, due to their defective understanding of energy transfer within the atmosphere.

9. tallbloke says:
November 16, 2010 at 6:38 pm
Somebody took off the lid which covered the earth without telling it to the IPCC 🙂

10. tallbloke says:

Actually, Trenberth already acknowledged a year ago that his energy budget is up the spout:

From: Tom Wigley
To: Kevin Trenberth
Subject: Re: BBC U-turn on climate
Date: Wed, 14 Oct 2009 16:09:35 -0600
Cc: Michael Mann , Stephen H Schneider , Myles Allen , peter stott , “Philip D. Jones”

, Benjamin Santer , Thomas R Karl , Gavin Schmidt , James Hansen , Michael Oppenheimer

Kevin,

I didn’t mean to offend you. But what you said was “we can’t account
for the lack of warming at the moment”. Now you say “we are no where
close to knowing where energy is going”. In my eyes these are two
different things — the second relates to our level of understanding,
and I agree that this is still lacking.

Tom.

++++++++++++++++++

Kevin Trenberth wrote:
> Hi Tom
> How come you do not agree with a statement that says we are no where
> close to knowing where energy is going or whether clouds are changing to
> make the planet brighter. We are not close to balancing the energy
> budget
. The fact that we can not account for what is happening in the
> climate system makes any consideration of geoengineering quite hopeless
> as we will never be able to tell if it is successful or not! It is a
> travesty!
> Kevin

11. lgl says:

Six studies found the emissivity of sea water to be 0.97 – 0.99

Click to access 50010017.pdf

12. tallbloke says:

Thanks lgl, the info in the abstract of that paper is useful to the realclimate – Minnett experiment debate.

The sea surface emissivity in the infrared region is determined on the basis of data
variables are measured throughout most of the year at the oceanographical
observatory tower in Tanabe Bay, Japan. We have found that 0.984 ±
0.004 is a reliable emissivity value from the night time data. Surface emission
radiates not from the subsurface water but from the sea surface. The thermal skin
layer on the sea surface, however, is disturbed and disappears under high wind
speed over 5 m/s through the analyses of the radiation observation using the
emissivity value of 0.984. Under low wind speed, the sea surface can be cooler or
warmer than the subsurface due to overlying thermal conditions, and the skin
layer can be neutral as the transient process between them. By using an emissivity
value of 0.984, the temperature difference between the sea surface temperature
and the temperature determined from surface irradiance that has been reported
in the satellite data analyses is found to be reduced by half.

.

13. E O'Connor says:

Tallbloke said
“I suspect the ‘missing heat’ already left the building through a window………”

Maybe that’s one of the hidden elements of NASA’s GLORY Mission scheduled for launch in early 2011.

Based on Glory’s data, the first line of the chorus from ‘The Battle Hymn of the Republic’ will be sung by some –

“Glory, glory, hallelujah!”

And then we will be one step closer to Leonard Cohen’s ‘Future’ where
“Things are going to slide, slide in all directions
Won’t be nothing
Nothing you can measure any more”
-:)

14. Tenuc says:

Perhaps we need to go back to basics and find a way to check climate metrics. withpugh having to resort to algorithms based on untested assumptions built on falsified conjectures like CAGW. Back in the ‘real’ world, many of the lessons learned from earlier climate science has been conveniently forgotten:-

Global mean temperature is a poor proxy for total thermal global system energy.

Thermal energy is a poor proxy for total global system energy, which includes EM and mechanical potential and kinetic.

Energy can be translated from one form to another with varying degrees of efficiency. So no surprise when thermal energy suddenly appears or disappears in our turbulent climate system.

The Earth is never in a steady state of ‘energy balance’. rather it oscillates up and down around some notional ‘mean’; the mean itself varies and is dependent of the time-period chosen.

In view of these inconvenient facts, perhaps no surprise that even Trenberth admits, “We are not close to balancing the energy budget. The fact that we can not account for what is happening in the climate system makes any consideration of geoengineering quite hopeless as we will never be able to tell if it is successful or not! It is a travesty!”

It is also impossible to get a good measure of the amount of back radiation from Earth. The black-body ‘laws’ only apply in ideal conditions and in the real world they fail because it is impossible to take into account the wide variations in boundary conditions which can be observed at any moment in time across every square metre of planet surface.

15. @Tenuc:
Energy can be translated from one form to another with varying degrees of efficiency
You are absolutely right. All fields’ (-which are one, btw) changes should be considered, simply because there are not separated compartments in nature. You just don’t ask for “heat” when needing to make your breakfast, you ask for POWER.

16. tallbloke says:

I don’t claim to be any kind of expert on radiative energy trasfer in the atmosphere, but I seem to have got the impression from reading some papers that the radiation from the sea surface gets absorbed pretty quickly in the first few metres of the atmosphere, and then the major mechanism for transporting the energy is convection. But I would assume that the convecting molecules happily re-radiate and reabsorb LW radiation from their surroundings as they ascend in the convective flow. So is this why there is an argument between G&T and the atmospheric physics climatologists? One group are looking at what actually matters in terms of the energy shifting process, while the other are fixated purely on the radiative physics?

Is DLR measured at the surface actually measuring DLR from quite near the surface which was only recently emitted from the surface?

17. Tim Channon says:

What happens when it rains?

18. gnomish says:

and does H2O phase change, which moves heat by the freightload and occurs with virtually no temperature change, show up as a variation in the BB radiation spectrum?
i think not

19. Bill Illis says:

All these equations / diagrams are only done in two dimensions – area.

There needs to be four dimensions.

There needs to be length, width, height and time.

Science of Doom started down this road a little in his latest post. [It takes 2000 days (6 years?) for the inside of the PVC sphere to reach its temperature equilibrium? That is a little wierd and is a non-physical result].

On the actual Earth surface, the Solar energy is often quoted as 240 watts/m2 on average but this is more accurately described as ==> 0 joules/m2/second at night and 960 joules/m2/second at the height of the day.

1 Watt/m2 = 1 Joule/m2/second

The energy held in the atmosphere for a square metre area at 2 metres height above the ground almost immediately transfers all of the solar energy up and out during the height of the day.

960 joules/m2/second in : 959.9983 joules/m2/second out.

At night, it is 0.000001 joules/m2/second in : 0.001 joules/m2/second out.

Given the average mean path of a photon and the average relaxation time for an excited molecule and the number of collisional energy exchanges per second amongst atmospheric molecules …

… the initiation point for the “back-radiation” is just millimetres above the instrument measuring it. It is not coming “down” from the Tropopause – it coming from 2.000001 metres above the ground. It is a fraction of a second of random walk downwards on the steady stream outwards of the long-wave radiation.

Emmissivity is ~1 when the radiation is flowing back-out on a one-for-one basis with the solar radiation coming in (when time is finally considered in the equations).

In = Out

959.9983 joules/m2/second out is 99.9998% of the energy coming in.

20. tallbloke says:

Hi Bill, thanks for dropping by. What you are saying pretty much accords with my intuition of what is happening, but a couple of things I need clarification of in what you say.

“The energy held in the atmosphere for a square metre area at 2 metres height above the ground almost immediately transfers all of the solar energy up and out during the height of the day.”

And this is due mainly to ‘free’ convection – right?

“Science of Doom started down this road a little in his latest post. [It takes 2000 days (6 years?) for the inside of the PVC sphere to reach its temperature equilibrium? That is a little wierd and is a non-physical result].”

Wasn’t it that it takes that long before the outside of the sphere is radiating as much as the central power source emits?

21. Bill Illis says:

Convection is certainly part of the outgoing radiation, but it must be a smaller amount. Air rises when it is warmed but there is always air coming in to replace it. There is so much radiation flow out that the majority must be simple emission and collisional energy exchange.

It should be noted that air temperature declines by 0.0065C every metre as one goes up and the energy held in the atmosphere declines by 0.036 watts/m2 for each metre up. So, there is just a small differential each metre but the energy is continually moving up and out, even at night when convection processes mostly stop.

22. Do you remember that the fastest energy displacements occur in Hurricanes and Tornadoes?
How do these work?

23. tallbloke says:

Bill says:
the initiation point for the “back-radiation” is just millimetres above the instrument measuring it. It is not coming “down” from the Tropopause

Bill, yes, this is what struck me that is misleading about the K-T diagram, and is likely part of the reason Nasa have omitted those seperate up and down ‘flows’ in their newer budget diagram, and simply given a ‘net’ figure.

24. Bryan says:

……”and is likely part of the reason Nasa have omitted those seperate up and down ‘flows’ in their newer budget diagram, and simply given a ‘net’ figure.”……

When will SoD learn that just about everybody else has moved on?

25. tallbloke says:

Well S.o.D bless his radiation proof cotton socks is intelligent enough to realise that without significant downwelling co2 flux the whole AGW argument crumbles…

I’ve just been reviewing the spanking meted out by Nasif Nahle to S.o.D and DeWitt Payne on this old S.o.D thread:

26. It’s true. If there is no downwelling radiation from CO2, then not only is AGW falsified, but a large chunk of radiative physics.

Intermission: You can get away with misrepresenting and post editing what I say on your blog, but you can’t get away with it here. I have bolded the relevant words in my comment and your reply so people can see how you twist what other people say. Now the rest of your straw man argument…

Best to pretend it’s not there. After all if someone somewhere anywhere publishes a net figure it has definitely “reduced” the real value. Like putting your hands over your eyes – but even better. Or like publishing your net income and pretending that your outgoings are therefore much much less, or probably don’t even exist..

However, I’m sure there are many people visiting this blog who are interested in science instead of tall stories.

For those people, there is a high quality network of stations around the globe that measures “back radiation” from the atmosphere. You can see the data in The Amazing Case of “Back Radiation”. You can see samples of the results as well as summary data. You can see that the measurements are in the order of 300 W/m^2.

tallbloke clearly has a problem with these measurements otherwise he would realize that “the spanking” by Nasif Nahle is easily falsified by “the measurements”. Nahle claims that according to his calculations there is almost no downward radiation from CO2.

tallbloke doesn’t like to be pinned down when asked direct questions, so I won’t embarrass him by getting him to say whether he thinks back-radiation actually exists, or what its value is, or how inaccurate he thinks the measurements are. That would be ridiculous, because then there would be the possibility of falsifying his claims.

People endorsed on this blog:

-G&T claim to believe that “back radiation” exists and reaches the earth’s surface but don’t feel obliged to say why it disappears (because they don’t believe the “greenhouse” effect exists)

-Nicols believes in the “greenhouse” effect but believes it won’t increase very much with more CO2

-Nahle believes there is almost zero “back radiation” from CO2, but can only explain the spectral results by not being able to convert from W/m^2.sr.um to W/m^2 – and thereby claiming that there is no “back radiation” from anything, whether CO2, water vapor, or any other trace gas.

So each of these three contradict each other. As explained in New Theory Proves AGW Wrong.

United in “Not Believing Stuff we Don’t Like”. At least all in agreement on something.
Very entertaining.

27. Bryan says:

scienceofdoom

A favourite line of reasoning by AGW believers goes as follows.

…..”A radiative colder object is brought closer to a radiative warmer object.
The photons from the colder object strike and are absorber by the warmer object thus increasing the temperature of the warmer object”….

Lets try another thought experiment.

An object at say 30C is radiating to its surroundings.
Then an object is brought close to the 30C object.

I think all people agree with the following;

If the object is also at 30C there will be no flow of heat between objects.

If the object is at 10C the flow of heat will be from the 30C to the 10C

If the object is at 90C the flow of heat will be from the 90C to the 30C.

The point being a 30C object can at the very best heat another object up to a maximum of 30C

As a frequent visitor to your site I know you have covered many topics.

The one topic you have not touched on is a the science behind a refrigerator.
We would all agree that this device can transfer heat from a colder body to a hotter one.
I think that you would learn a lot from the study of the thermodynamics behind the Carnot cycle and the refrigerator.
The thought has just occurred to me that perhaps in Climate Science courses the Carnot cycle and the refrigerator are missed out because it does not apply to the Earths climate.
This would explain why there is such confusion about the direction of heat travel.

28. gnomish says:

The co2 fetish is concerned with BB radiation, not watts.
When you count the joules, CO2 has nothing compared to the phase change of water in the same volume of atmosphere.
Degrees can not be converted to watts.
The ‘missing heat’ effect is a signature of the CO2 fetishists. They don’t see phase change and refuse to address it.
Yup, it’s a heat pump just like a fridge – it’s not a degree pump.

29. tallbloke says:

S.o.D says:
-Nahle believes there is almost zero “back radiation” from CO2, but can only explain the spectral results by not being able to convert from W/m^2.sr.um to W/m^2 – and thereby claiming that there is no “back radiation” from anything, whether CO2, water vapor, or any other trace gas.

I think you both made errors in assessing that figure. I notice you didn’t respond to Nasif’s demonstration of yours.

30. Bill Illis says:

Science of Doom.

Noone disputes that radiation is not flowing up, down, sideways, in circles etc. Noone disputes that CO2 has a strong absorption band in the IR. The problem is the explanation is incomplete and does not describe what is really happening at the surface. The math does not work.

There is a network of surface radiation measuring sites across the world – these are the US ones.

Here are the numbers for November 17th, 2010 for Table Mountain Colorado.

Energy level at 2 metres implied from the Temperature measurement, Net Solar Radiation In, Upwelling IR, Downwelling IR and the net change in the energy level implied by the surface temperature. (Actually, the Upwelling IR more closely matches the surface temperature than anything else).

And then how the measured radiation flows compare to the actual change in 2 metre atmosphere temperatures.

Obviously, this framework does not match what it is really going on.

31. tallbloke says:

Nasif Nahle says:
July 28, 2010 at 5:52 pm

Dear John Eggert,

Your concern is valid. However, for calculating the total emissivity of the carbon dioxide at its current mass fraction in the atmosphere I applied the following formula:

ECO2 = 1-[(a-1 * 1-PE / a + b – (1 + PE)) * e [-c (Log10 (paL) m / paL)^2]] * (ECO2)0

Which was taken from Modest book on radiative heat transfer.

The correction factor (ECO2) was taken from tables on total emissivity of the carbon dioxide by Hottel, Lecknder and other authors. From those charts, I read that the total emissivity of the carbon dioxide at a pCO2 of 0.05, a pabs of 1 bar cm, and a T of 300 K the total emissivity of the carbon dioxide is 0.008, although it was the outcome of experimentation. So I calculated the emissivity of the CO2 at the same physical conditions and found the ciphers given by those authors were correct.

But we are not talking about the actual current pCO2 in the atmosphere, but a pCO2 (0.05 bar cm) which is ~132 times higher than the actual pCO2 in the atmosphere.

Therefore, I applied the following formula for knowing the correction factor (ECO2) by which I had to multiply the observed total emissivity of the carbon dioxide:

ECO2 = [e ((|√ Log10 (290 K * T∞)| / (- c * 1 K)] * [pCO2 * 100 / 5 (pabs)]

which gave a magnitude for the total emissivity of the carbon dioxide of 0.0017.

This figure must be multiplied by the correction factor obtained from the first side of the formula, that is, by 1-[(a-1 * 1-PE / a + b – (1 + PE)) * e [-c (Log10 (paL) m / paL)^2]] , which is 0.999948. Therefore, the total emissivity of the carbon dioxide at its current mass fraction in the atmosphere is 0.999948 * 0.0017 = 0.001699. or 0.0017 by rounding up the cipher.

The formula you suscribe in your post, delta F=5.35 * ln[CO2/CO2o] is incomplete because the figure 5.35 has units W/m^2, so the magnitude F would have units W/m^2. Nevertheless, the concept F must have units °C / W m^-2 if F is referring to Tsens of the carbon dioxide.

The same problem appears in the formula ΔT = 5.35 W/m^2 * LN [CO2/CO2] because the outcome would be in W/m^2, not in K or in °C.

32. tallbloke says:

Just thinking about NASA’s new diagram a bit more, it has:

“Conduction and rising air” 7%
“Carried to clouds and atmosphere by latent heat in water vapour” 23%

“Rising air” we readily understand as “free” convection, but what is this “carried by…” all about?

The 23% of energy travelling as latent heat is also freely convecting it’s way up to the clouds in the water vapour, because water vapour molecules are much lighter than air. So convection is shifting around twice as much heat as LW radiation is, since the net value of the up/down/round’n’round swoosh of LW results in only 15% of the energy budget being shifted from ground to sky.

33. tallbloke,

I barely responded to Nahle at all. Not much point on that. Why don’t you explain whether you think he is correct or not on a specific point and I will be happy to explain.

De Witt Payne spent some time explaining what was wrong with Nahle’s point. I realize that many people are taken in by those who produce pages of maths regardless of errors. So I pointed out the obvious problem of experimental results. Everyone (almost) can grasp hold of that idea.

Nahle says there is no backradiation from CO2.
I say that this result is measured and significant.
I provided measured flux results (W/m^2) of back radiation.
I provided measured spectral results (W/m^2.sr.um) of backradiation and showed how to convert between the two.

There is “back radiation”. It is significant. We measure it every minute of the day in W/m^2 and every time someone does a spectral measurement it has similar characteristics with a significant portion from CO2.

I wrote my comment earlier because many people reading your blog might think that what you “obviously appear to believe” was true. What you “obviously appear to believe” is that back radiation from CO2 is not significant.

As and when you explain your real thesis about back radiation I will be happy to comment on it.

P.S. You obviously think Nahle is someone worth spending time on. Perhaps you endorse his quite outstanding claim that the measured spectral results from one of the papers cited are produced from a model? I pointed out that they are measured results. Nevertheless, Nahle continued to claim that the authors themselves said the results were not measured (was the FTIR just for the photoshoot?). Understandable – the alternative would be that Nahle didn’t have a clue how to do his calculations.

Still if he does a lot of maths and backs up what you “obviously appear to believe” he must be right.

He “spanked us” alright.

34. tallbloke says:

Ok S.o.D, I’ll compile a list of the things I think Nasif got right and wrong, and the same for DeWitt and yourself. Then we can work it out in gentlemanly fashion, hopefully with their assistance.

35. Leonard Weinstein says:

36. tallbloke says:

Hi Leonard,
Thanks for stopping by again to try to educate us. 😉
I think your analysis sounds plausible. I wonder what, all else being equal, the effect of raising the height at which radiation to space occurs at is. Intuitively, it might ‘thicken the blanket a bit’, leading to more heat being held in the atmosphere for slightly longer. As I understand it, the effect is fairly small in linear terms, around 1% height increase for a co2 doubling. Have you calculated what effect that would have if nothing else in the climate system compensated for it?

37. Bryan says:

I agree with Leonard Weinsteins emphasis on the central role of convection in explaining the mechanics of the climate that we observe.
It modifies the lapse rate set up by gases operating in a gravitational field.

The radiative effects of the trace gas CO2 are insignificant compared to the radiative effects of H2O which also shows phase change effects that explain much of what we see.

Woods experiment shows that Greenhouses only work by stopping convection.
The remaining small radiative effect (real though it is) is almost negligible.

Where the radiative effect is important is to let pass the longwave radiation to space.

Thus indeed we have radiative effects in the atmosphere that some choose to call the “atmospheric greenhouse effect” however its effects have been greatly exaggerated by scienceofdoom and the IPCC.

38. Leonard Weinstein says:

Tallbloke
For a good discussion on CO2 feedback, look at http://www.palisad.com/co2/eb/eb.html .There is a slight error in the initial statement of 20% increase for the period he quoted (it is close to 15%), but the rest supports the ideas of Roy Spencer, that feedback from water vapor to clouds drops direct CO2 increases in temperature from doubling CO2 from 1.2 C down to 0.5 C with negative feedback included. A gain of 0.5 C corresponds to a change in effective outgoing altitude of only 77 m. The altitude for outgoing radiation presently is about 5000 m. Thus the effect of doubling CO2 is about 1.5% change in outgoing altitude. The CAGW supporters predict a 3 C increase for a CO2 doubling with positive feedback, which would give a height change of about 500 m. It is not easy to determine this altitude change directly, so indirect effects are used to try to get the actual results.

39. Leonard,

I thought you knew that I agree with you about how the “greenhouse” effect works as we have discussed it a few times before.
And I have the same explanation at The Earth’s Energy Budget – Part Three and in many other places.

The reason I keep explaining to people that “back radiation” exists and is a significant amount is because so many people keep saying it doesn’t exist. As a reasonable person would conclude from the congratulatory statements like this, and others.

And when you explain the “greenhouse” effect to a lot of people they say “that can’t happen because..” – cue mistaken argument 1 – the surface radiation cannot be any higher than the radiation from the climate to space, cue mistaken argument 2 – the imaginary second law of thermodynamics. (Plus a whole host of other red herrings)

So if you review what I have written as comments on this article I am simply pointing out that DLR exists and the value is well-known and significant.

Most people who comment on this blog don’t believe these basic points. It appears the blog owner doesn’t believe it either but he doesn’t like making clear statements on this subject.

If the discussion was about how the “greenhouse” effect functions in totality, I would have different comments.

40. tallbloke says:

If S.o.D. re-reads my introductory post with a less jaundiced eye, he might realize that in fact I have left the subject as an open question, and I’m happy to host a range of different views on the issue. This is because unlike him, I realize that there are a number of conflicting, but plausible ideas about the nature and extent of ‘the greenhouse effect’ and the nature of the interactions of long wave radiation with air and water vapour, it’s path lengths and it’s sensible heating action which are worth exploring. My personal view is that it is entirely possible that the greenhouse effect works pretty much as Leonard says it does, and yet it hasn’t affected Earth’s surface temperature, because the atmosphere works along the lines of Miskolczi’s theory, and the ocean isn’t directly heated by LW to more than an insignificant extent anyway.

My main point in the original post is that the old Kiehl-Trenberth “sketch” is misleading in the way it presents the main energy flows in the climate system. Convection shifts twice as much energy from surface to upper troposphere as LW does, yet the K-T diagram on a cursory inspection seems to be dominated by radiation. The new NASA sketch is a step in the right direction but also minimises the dominant role of convection through obscure labelling.

Why might this be?

My second point in the original post is that the Earth can’t be treated as a blackbody, in fact, due to it’s internal flows and biologically covered surface it can’t be treated as a simple greybody either. The false precision inherent in treating Earth as a blackbody using the S-B equation is part and parcel of the ‘science is settled’ nonsense promulgated by the IPCC. As well as the errors this leads to in assessing the effect of additional co2 in the atmosphere, it leads to errors in assessing the role of solar variation in affecting Earth’s surface temperature, so the differences S.o.D thinks are negligible are likely compounded.

41. It’s wonderful to host a range of opinions. We must leave this as an open question. “Back radiation” can be anything between 0 and 350 W/m^2, or 0 and 1000 W/m^2. Or 0 and 10,000 W/m^2. All are possible. It is impossible to have any certainty on measurements of this value.

For those interested in boringly restrictive measurements and facts, the measurements say the cold hard facts put the global annual average value at 340 W/m^2.

That’s obviously wrong because it doesn’t support a range of opinions so I won’t point this out again here. In fact, it’s proven wrong by its definitive nature.

I won’t point out “errors” in tallbloke’s confident assertions because this would be against the idea of hosting a range of ideas. And if I did, I would find he was just putting forward ideas that were interesting, not ones he actually believes.

I get confused because tallbloke seems to support certain points of view and claim certain things are clearly wrong – yet, on questioning, all ideas are possible, and all are embraced, and no, he didn’t support them, he hosts a range of views and is interested in the wider subject.

People are welcome to discuss falsifiable science on Science of Doom. It’s a different approach.

42. tallbloke says:

Though you’ll find that if you do, and S.o.D. finds your approach to the ‘facts’ he asserts inconvenient, you may find your posts being edited without explanation after you submit them.

Your sarcasm is a cover for your inability to engage with the reality of uncertainty, your exaggeration of what others say and mean is an indication of your intellectual dishonesty, and your propaganda for the correctness of Keihl and Trenberths energy budget sketch is busted by Trenberth’s own admission that:

“we are no where close to knowing where energy is going or whether clouds are changing to make the planet brighter. We are not close to balancing the energy budget. The fact that we can not account for what is happening in the climate system makes any consideration of geoengineering quite hopeless as we will never be able to tell if it is successful or not! It is a travesty!”

To spell it out, the ‘falsifiable science’ S.o.D presents along with the implied assertion that Keihl and Trenberth are correct because the radiation flows in their misleading ‘sketch’ can be measured form what is known to logicians as a non sequiteur; i.e the theoretical correctness of S.o.D.’s simple energy flow model does not speak to the correctness or otherwise of Kiehl and Trenberth’s characterisation of energy flow in the real world, or the conclusions S.o.D thinks can be drawn from it. The dominance of convection in the energy flow from surface to atmosphere, obscured by Kiehl and Trenberth and NASA’s representations, changes the game.

This is because those convective flows take energy from hotter parts of Earth’s surface to places where loss of heat to space predominates over back radiation from co2 and water vapour in the atmosphere and so do not conform to ‘global average’ quantities like 340W/m^2. To understand the real world energy flows The Earth is best characterised as a heat engine, and the failure of radiative physics specialists is their failure to appreciate that global average radiation quantities and the Stefan-Boltzmann equation are inadequate for a complete understanding of the Earth’s climate and the magnitude of any ‘enhanced greenhouse effect’.

You’ll find that over on S.o.D’s blog, these simple truths are blatantly ignored if you try to get them discussed. Here however, people are welcome to bring a diverse range of expertise and knowledge to the debate, and it will not be treated with the condescension or disdain so commonly found on blogs run by people who think they already have all the answers.

43. Bryan says:

tallbloke

You are quite right to be sceptical about any value of atmospheric radiation measured by use of instruments such as the pyrometer.

http://www.pyrometer.com/Tech/emissivity.html

If you Google “pyrometer” and “errors in” or such like you will get pages and pages of examples of resultant gross errors.

Its certainly not like a metre stick accurate to 0.05%

De Witt Payne gave me a link to a new pyrometer which claims to be more reliable but only time will tell if it is.

Why should they be so unreliable?

Perhaps the reason is they are calibrated using assumptions about black bodies and use of the Stephan Boltzman equation.
Thus the whole farrago could be based on circular reasoning and false assumptions.

Contrast this with a statement From C.J. Adkins from Cambridge University in his book Introduction to Thermal Physics page 92.

Bolometers used in radiation measurements where the temperature differences are small between source and instrument (such as in atmospheric measurement) then Newtons Law of Cooling should be used for calibration.

Several other sources back this up.

Why should that be?

The well tried method of Newton makes allowances for conduction , convection and wind effects and is known to give more accurate results.

The pyrometer on the other hand may give more accurate readings when used in space or for larger temperature differences.

So when scienceofdoom or any other IPCC supporter asks you if you agree for instance that the Average Earth Surface radiation is precisely 396W/m2 then an open mind is far better than false certainty.

Especially when Woods experiment and several other bulk measurements say that the atmospheric radiative effect is almost negligible.

44. tallbloke says:

Bryan, If you look at what Doug Hoyt has to say about pyrometry, it’s clear he recognises the problem of absolute calibration, but more interesting is his take on the fact that this does not matter for the purpose of comparing it’s assessments of optical depth across large time spans and differing pyrometry hardware platforms. What is even more interesting is his assertion that in the locations he has studied, optical depth is almost unchanged across the entire history of pyrometry measurement. This is evidence contrary to the convenient increase in aerosols claimed by the co2 atmospheric modelers for the postwar cooling period in order to save their co2 driven temperature scenario.

Doug Hoyt’s page listing problems with the IPCC scenario is here:
http://www.warwickhughes.com/hoyt/climate-change.htm

I’m having trouble finding the pyrometry reference just now.

45. Leonard Weinstein says:

Scienceofdoom,
I apologize for mis-stating your understanding. The repeated emphasis on back radiation made me think you were claiming this as a source of heating. I think we agree on the basics, and still disagree on the feedback level.

Tallbloke,
If you agree with my basic discussion, then you are agreeing that atmospheric greenhouse gases do cause some heating. It may be small, but it is real. The actual argument is how small or large, and this depends on such things as clouds and aerosols, which are not yet well understood.

46. tallbloke says:

Leonard, I understand your basic discussion, and that water vapour and co2 and other ‘greenhouse’ gases maintain the Earth’s energy balance such that it has a higher temperature at the surface than it would have if they weren’t there.

However, it can’t be logically deduced from this that the recent increase in co2 levels is responsible for any of the recent warming of Earth’s surface temperature.

It may well be that it is responsible for some of it, but it ain’t necessarliy so.

IPCC estimates of climate sensitivity rest on two key issues. One is water vapour feedback, which according to the only reasonably long empirical data series we have (radiosonde) is in considerable doubt. The other is the amount of warming there has been compared to the amount of co2 level increase. Given that we still don’t know the magnitude or even in some cases the sign of the effect of various natural variations, the estimate the IPCC derives is necessarily in considerable doubt.

That they assign a 95% confidence value to their assertion that the majority of the temperature change is down to human emission of co2 is laughable, illusory and dishonest.

47. Leonard Weinstein says:

Tallbloke,
Why do you think I call myself a skeptic. I do agree that I doubt that much of the rise over the last 150 years is due to the CO2, and the IPCC is way off base in their claims. However, the best science would indicate that CO2 would have some effect, and this is what I have been trying to zero in on. I also clearly do not believe we have a CO2 problem going into the future, but I am keeping an open mind to new data. This is not an either or problem, but a how much one.

48. tallbloke says:

Our positions are close, although my current position is ‘how much of a problem, if at all?’, given Ferenc Miskolczi’s currently unrefuted theory, and the uncertainty of the sign of the cloud feedback.

49. gnomish says:

Water gas is the lightest consituent of the atmosphere (not counting helium or hydrogen which exist in fractions of a percent).
For water gas to ascend to the infinite heat sink in the sky does not even require convection- however convection seriously increases the buoyancy of that already buoyant gas.
There is a constant flow – the Hadley cells, precipitation charts and all else show the daily process quite clearly on a global scale.
CO2 doesn’t just hang out on the surface- it goes along for the ride. Nor does the sum total of that gas in any volume of our atmosphere carry 1/50,000 of the heat that the water gas does – and the water gas does not need to change temperature at all to radiate the joules it carries when it gets to condense as a cloud.
Radiation physics is appropriately applied at the radiator end and the boiler end of this heat pump system – but in the middle- no, it doesn’t insulate- because the flow is constant. In point of fact, any increase in heat capacity of the working fluid improves the efficiency of the heat pump. No it does not contribute to heat retention in any significant way – it’s moved on the real heat conveyor in a flux – it’s just a passenger and it’s sent to the cooler every day with every other gas on the conveyor- it has no heat of vaporization, no heat of solidification.
The CO2 fetish is a psychological disorder- similar to the puritanical fear of nipples.
The only purpose it serves it to distract from making productive use of one’s time and as a rationale for taxing your breath. It has been a very successful tar-baby and neutralized a significant amount of rationality, much like any deep and sincere discussion of how many angels dance on a pin. It’s fraudulent. It’s a trick. It’s not wholesome and not healthy and it costs the addicts as much as heroin addiction- but they don’t pay for their own drugs.
It numbs you and disables critical thinking and it’s not even a sweet siren song and doesn’t get you high. it has one purpose only – to cripple rationality and render folks insensible to predation. It’s leech saliva.

50. Bryan says:

Correction to my post above

….”De Witt Payne gave me a link to a new pyrometer which claims to be more reliable but only time will tell if it is.”…….

for pyrometer it should be pyrgeometer

51. Bryan says:

tallbloke

…”If you look at what Doug Hoyt has to say about pyrometry, “…

Thanks for the link and it seems a good comparison table of IPCC model prediction versus reality.

52. tallbloke says:

pyrgeometer

Ah, that’s why I couldn’t find the reference.

Here we are:

Click to access fulltext.pdf

Interesting that Hoyt was working with Claus Frohlich at this point. Their views seem to have diverged since.

53. My closing comment on this blog – tallbloke’s claims on November 21, 2010 at 10:15 am of my dishonesty are false.

However, his comment has been effective in at least one of its intended results.

54. tallbloke says:

Not only does S.o.D have all the answers to the physics of the climate but he also knows I had some kind of ulterior motive for making my comment about his exaggeration of other peoples meaning and certainty about what it was!

Amazing!

I just can’t understand why the worldwide controversy around climate science that has been raging for the last 20 years hasn’t been solved to everyones satisfaction by S.o.D.s brilliant incisive analysis and handwaving yet.
/sarc

S.o.D if you ever come to realise as Trenberth has that;

“we are no where close to knowing where energy is going or whether clouds are changing to make the planet brighter. We are not close to balancing the energy budget”

please feel free to come on over again for a reasonable discussion between people who can regard and discuss each others points of view concernng a young and highly uncertain branch of science without rancour, sarcasm, or supercilious condescension. I give as good as I get, and I’m sure we both have good stuff to give.

55. Tenuc says:

tallbloke says:
November 23, 2010 at 8:50 am

“…I just can’t understand why the worldwide controversy around climate science that has been raging for the last 20 years hasn’t been solved to everyones satisfaction by S.o.D.s brilliant incisive analysis and handwaving yet…”

The context behind Trenberth’s ‘travesty’ comment is interesting and can be found in his paper here:-

Click to access EnergyDiagnostics09final2.pdf

The paper contains so many ill founded assumptions that it is no surprise the numbers don’t add up. The approach is also wrong as it fails to understand the dynamic non-linear nature of the problem. The climate Trenberth tries to describe just doesn’t exist outside of a computer model.

56. Tenuc says:
November 24, 2010 at 3:33 pm
They should have made, instead, a real CLIMATE GAME to sell it next Christmas; others already made it, so they failed this time too.

57. I got it!. Do you know what happened to back radiation?…Someone issued bonds of it (under several convenient names, of course) and by now that someone has it saved as metallic gold in some tax-free “paradise”

58. David says:

Good discussion, and as a layman commenting on blogs I probably am not qualified to comment at, I appreciate all education on a matter with severe public policy implications. I comment on occasion to receive answers to questions that arise from reading all you “educated” folk, and perhaps for your educational feedback on what an average layman can comprehend or not from the questions at hand. I found Bill Illis comment on Nov 19 at 1:32 to be very instructive, “All these equations / diagrams are only done in two dimensions – area. There needs to be four dimensions. There needs to be length, width, height and time. Time and latitude are a factor for many reasons.

I find the two Earths energy budget charts very interesting. In some ways I like the first black and white one because of the Wm/2 are easier to compare to the estimated increase (whatever the actual value is) in back radiation due to a doubling of CO2. All factors of course vary tremendously by time of day and latitude. Given that, it is interesting to note that at least 144 Wm/2 are subject to changes in Cloud and water vapor content. This alone must overwhelm any back radiation warming from CO2. Also the estimated 78 W/m2 transported as latent heat through evaporation is by itself far greater then the any CO2 induced warming.

But again time of day here is critical. Given Bill’s 960 joules/m2/second at the height of the day (at what latitude?) is almost three times the 342 Wm/2 shown in the charts, then the TSI affected by cloud and water vapor could be about 420 Wm/2 during the day, and the estimated 78 Wm/2 given for evaporative latent heat transfer would also be far higher. Therefore any change in evaporation rate, water vapor and clouds would be operating on these far higher numbers, further overwhelming any CO2 effect during the day. This could help explain why some people have stated that the CO2 warming signature is noticed in the thermometers mainly at night in the winter. Not only can these changes in water vapor, evaporation and cloud cover overwhelm CO2, leaving them unchanged, just moving them latitude wise can effect these numbers trmendously.

“Time” is also a critical dimension for this as I have noted on another comment here;
David says: (December 2, 2010 at 2:33 pm Frank on the realclimate ocean heating experiment) This thought is summarized as “Water vapor and clouds effect a much larger portion of the TSI then CO2, and effect it not only at the LW spectrum in the atmosphere, but where it matters the most, at the SW spectrum entering the oceans. Any change in the input or the residence time on this 1,000 hour road will have a 100 times greater effect then on the 10 hour road. For a more articulate presentation of this concept please read the December 2, 2010 at 2:33 pm post. Once I understand how “residence time” affects energy accumulation I will not bother you folk again until more clear questions arise.

59. Bryan says:

tallbloke

SoD is back on the heating the Ocean theme.

Does he mean that all DLR (downward longwave radiation) which he calls “back radiation” must have come “back” from Earth Surface?

Is there no Direct from Sun through atmosphere interactions source of DLR?
He wouldn’t give me an answer so I thought Id ask you

60. tallbloke says:

Hi Bryan. I haven’t read SoD’s new piece yet.
If you look at the two energy budget diagrams at the top of this post, Trenberth reckons 67W/m^2 of incoming solar energy is absorbed in the atmosphere. NASA think 16% plus 3% in clouds of 342 incoming.

This energy will be partly re-emitted as LW, which goes up as well as down.

61. Bryan says:

tallbloke – thanks.

Yes 19% of incoming absorbed and perhaps up to nearly 10% of incoming or 34W/m2 has not come back from anywhere and should really be added to 51% incoming making around 60% of solar landing at Earth surface.

62. tallbloke says:

Correct. This is another failing of the Kiehl-Trenberth energy budget sketch. The numbers all add up but the ‘provenance’ of the energy isn’t as clear as it should be. Possibly another reason NASA cut the up/down flux out of the picture and went with a net figure.

63. tallbloke says:

David, your observations are welcome here. Keep it coming.

64. tallbloke says:

David L. Hagen | December 5, 2010 at 6:16 pm |

Quote – Miklos Zagoni
“The longwave section of the Kiehl-Trenberth 1997 (= IPCC 2007 AR4 WG1 Chapter1 FAQ1.1 Figure1) is wrong, both in the concept and in the numbers. The definition of the “Atmospheric Window” in the text does not match with the physical quantity shown in their chart (see Miskolczi’s Comments on KT97). The value of it, given as all-sky top-of-the-atmosphere window flux, should be about 66 Wm^-2, instead of 40 W m^-2, given in both the original KT97 and in the updated Trenberth-Fasullo-Kiehl (TFK) 2009 BAMS publication.

A further serious problem is that KT97 used the U.S. Standard Atmosphere 1976 (USST76), with appendix B of Liou 1992, for vertical profiles of temperature and water vapor. But that atmosphere contains only about half of the real global average precipitable water. Calculating the greenhouse effect on that reduced GHG content, the KT97 distribution should have an atmospheric window radiation about 99 Wm^-2. This is even more unacceptable for real global average than the given 40 Wm^-2 value.
For the correctly defined physical quantity (surface transmitted radiation, ST , on the whole spectrum) in his set of data collection, Miskolczi’s computations give a global average value of about 60 Wm-2 (see Table 2 of his recent publication and his Table 1 and Figure 1 for definitions of the quantities). This number is close to what NASA measured on their instrument with their methods, and fits well with the required value of the equilibrium distribution.
Correcting the TFK2009 Atmospheric Window with the real global average, the resultant greenhouse effect again sits very close to the stable stationary value. In this sense, these quantities support the idea that the Earth’s greenhouse effect maintains a kind of constancy.”

65. David says:

Bryan what do you think about that 50% to 60 % which reaches the surface. Are they talking averages during a 24 hour day with the mean of all latitudes combined? Water vapor is the primary interceptor of incoming absorption and on a clear day it is at somewhere between 16% and 20%, clouds are additional and can be more then the 3% shown. What is it in the tropics in the afternoon after 7 to 8 hours of tropical sun has been beating on the ocean surface? Remember all these numbers can be about three times higher in the tropics.

My questions at this point are primarily directed at the effects of water vapor and clouds on SWR entering the ocean and on the earths energy budget relative to the “residence time” of changes in SWR versed changes in LWR.

“Residence time” is a term I use but have not seed discussed after several hundred hours of reading blogs and portions of papers linked on blogs.

In my view the controversy over LWR heating the ocean via a reduction in the gradient between the skin and the surface below the skin is a mute point even if sod is correct it can only slow the cooling. The heat comes from SWR entering the oceans. Any raising the temperature of the skin via DLWR will only speed the evaporative process, produce more water vapor and clouds which reduce the amount of SWR entering the ocean which of course REDUCES the temperature of the ocean below the surface, which by the way further slows the cooling yet the ocean temperature is still lowered. L.WR cannot “heat” the ocean.

If my very simple hypothesis is correct, this reduction in SWR penetrating the ocean has a potentially far greater impact on the earths heat content do to the mean residence time of SWR in the system being FAR longer then LWR. I have made a very simple analogy to residence time in a heat system with two roads as a metaphor for “residence time” and the traffic on that road as a metaphor for energy content within the system. For everyone who cares to read it I will restate it here.

1. At its most basic only two things can effect the heat content of any system in a radiative balance. Either a change in the input, or a change in the “residence time” of some aspect of those energies within the system.

2. On a highway if ten cars per hour enter the highway, and the cars are on the road for ten hours before exiting, there will be 100 cars on the road and as long as these factors remain the same the system is in balance. If you change the INPUT to eleven cars per hour, then over a ten hour period the system will increase from 100 cars to 110 cars before a balance is restored and no further increase occurs. The same effect as the increase in INPUT achieves can be realized by either slowing the cars down 10% or by lengthening the road 10%. In either case you have increased the energy in the system by ten percent by either increasing the residence time or the input.
3. Now lets us take the case of a very slow or long road with the same input. Ten cars per hour input, 1000 hours on the road, now you have ten thousand cars on the road. Now lets us increase the input to eleven cars per hour just as we did on the road with a ten hour residence time. Over a 1,000 hour period we have the same 10% increase in cars (energy) How ever due to the greater capacity on that road the cars, (energy) have increased 100 times, (1,000 verse 10 ) Any change in the input or the residence time on this 1,000 hour road will have a 100 times greater effect then on the 10 hour road.

This is cogent to climate in that the 10 hour road is the atmosphere, and the 1000 hour road is the oceans. Any change into the ocean input is going to have a FAR GREATER long term effect then an equivalent change in the residence time of energy in the atmosphere.

Tallbloke and anyone else; what I am looking for is an analysis of the above. If what I am saying about residence time is correct then it is exact and applies to the earths energy balance directly in proportion to changes in residence time. Cosmic factors such as solar changes which can last decades and cosmic ray changes which may last many centuries and possibly affect cloud formation can have very long term effects which overtime can accumulate either positively or negatively in the oceans. Even the small amount of UVR which enters the ocean may have a very strong long term affect as it penetrates up to 300m into the oceans where its residence time may be a thousand years. I am looking for criticism or confirmation of my statements. If they are correct I do not understand why this is not discussed more often. However if all my ideas are wet (excuse the pun (-: then I would like to know.

BTW Tallbloke, the pool experiment on SWR water heating verses LWR does not have to be deep. What heats a black bottom pool? I think it is the SWR. In that case the SWR would simply show the results faster and perhaps not as completely due to the fact that the residence time (think heat sink capacity) of an eight foot deep black bottom pool is not nearly as long as a 3000’ pool. However it would still show a dramatic difference between the abilities of LWR source above the surface and SWR to heat water.

66. David says:

Arrgh, I should type on a processor with spell check before I post, forgive the typos.

67. Bryan says:

David I think tallbloke is your best guide here.
I tend to stick to my strengths, basic thermodynamics and I avoid giving “of the cuff” opinions that could mislead people.
What Ive found with “climate science” is a very slapdash approach to the most basic of definitions hence my post above to tallbloke about whether it is customary for climate science to label all DLR as “backradiation” whether it came “back” from the surface or not.
Because of the confusion in quantities there is very little incentive for me to spend my time getting more irritated by examining AGW theory in detail.

68. tallbloke says:

Hi David,
I think the other factor you need to work into your cars example is the entropy. Those cars are going to have a lot less fuel left at the end of the 1000 hour road than they did at the end of the 10 hour road. Getting back to climate, water has a much higher specific heat capacity than air. So although air reaches a higher temperature quicker for given energy input, it also cools down and loses that energy quicker too.

This is why the warmists want to be able to claim the increased co2 level will cause the ocean to warm. It gives them more ‘residence time’ for extra energy trapped in Earth’s climate, and potentially explains a big ‘lag’ between the additional forcing and the manifestation of the energy in higher surface temperature.

Have a read of the John Daly repost I’ve just put up. He made a great job of explaining it.

69. P.G. Sharrow says:

I have an ongoing “greenhouse effect” experiment on my small farm as I like to have real data vers. dreamed up data from armchair “scientists” 🙂

A 3600 cuft. greenhouse dug into the ground, 4feet. After 4 years of use I added 250 gallon jugs of water. This greatly tempered the temperature swings in the summer and reduced the temperature drops in the winter. Oddly, serious changes in CO2 content inside had no effect on the temperature balance, although the plants really did like the higher CO2 levels. Higher water vapor, humidity, was also greatly apprecated by the plants but it did speed up the heat losses at night.

Results; Water has large “greenhouse” effects. CO2 has none that I can determine. 😉

70. P.G. Sharrow says:

During the design and construction of solar energy equipment, direct and back scatter radiation is considered. While the sun radiates large amounts of energy. It is only direct from the sun and the rest of the sky is cold space night and DAY. During the day there is back scatter energy from the atmosphere, the real greenhouse effect. This is mostly caused by the dust and water vapor in the atmosphere. To test just measure the energy difference of, in the direct sun, and then, in shade that is exposed to space, say on the back side of a large building to reduce atmospheric conduction.

As a solar power collector the oceans are a great design for the collection and storage of direct radiation. From the Antarctic circle to the Arctic circle a more or less self adjusting solar collector. Within the circles the angle is mostly worthless to get much penetration of energy into the water column. Water is a poor collector of backscatter energy as the penetration is very shallow and mainly just speeds up surface evaporation. Energy leaves the ocean, mostly through evaporation. The evaporation temperature of a body of water is set by the vapor pressure at the surface / atmospheric interface. While the energy temperature of a water molecule at the surface must go over 100c to jump free at “sea level”, the body of water may be as low as 0c a few mm below the surface.

The nature of a water molecule is that it occupies the least space at 4c and gets larger as it gets cooler or warmer then that temperature. As it gets larger, or lighter for the space, it rises. Warm water floats on cold water and very cold water floats on cold water! If this were not so, the oceans of the world would be solid ice with shallow seas, maybe a few 100 meters deep at the equator and solid at the antarctic or arctic circles.

71. Bryan says:

P.G. Sharrow

The paper below would be of interest to you.

Your findings that water is important might be down to the phase change(evaporation and condensation cycle).
When water has a surface as in droplets, clouds, pools it is a much better absorber/emitter.

The paper below is in line with your zero effect findings for CO2

It comes from a source with no “spin” on the AGW debate.

The way I read the paper is it gives massive support for the conclusions of the famous Woods experiment.

Basically the project was to find if it made any sense to add Infra Red absorbers to polyethylene plastic for use in agricultural plastic greenhouses.

Polyethylene is IR transparent like the Rocksalt used in Woods Experiment.

The addition of IR absorbers to the plastic made it equivalent to “glass”

The results of the study show that( Page2 )

…”IR blocking films may occasionally raise night temperatures” (by less than 1.5C) “the trend does not seem to be consistent over time”

Click to access penn_state_plastic_study.pdf

72. P.G. Sharrow says:

Yes, did study the paper. The IR blockers vers. none, show very small difference in heat loses from ground heat to space at night. The polyethylene films’ main function is to prevent frost damage to tender plants at night due to radiation loses.

My first greenhouse was a 13 x 20 foot hoop frame covered with 6mil. polyethylene. Cheap and worked quite well. Nice place to work in in the winter. 🙂 but I had to recover it every fall as our +100f summers just fried the plastic.:-( real pain in the rear.

73. tallbloke says:

Hi P.G.
Great insights on the oceans and water displacement, I’ll repost your thoughts on the Daly thread too. I have a polytunnel for my sald vegetables. Same piece of 6 mil plastic going strong after 8 years. 🙂

74. David says:

Re tallbloke says:
December 6, 2010 at 2:23 pm
“Hi David,
I think the other factor you need to work into your cars example is the entropy. Those cars are going to have a lot less fuel left at the end of the 1000 hour road than they did at the end of the 10 hour road. Getting back to climate, water has a much higher specific heat capacity than air. So although air reaches a higher temperature quicker for given energy input, it also cools down and loses that energy quicker too.”

Tallbloke please expand on this entropy. I understand energy can not be lost, only change form and or phase. Yes, of course it can dissapate or spread out, but as long as it is within the earth, the oceans, or the atmosphere, it is still within the system and is not less just because it is spread out. To me this entropy within the system is simply spreading the energy out to many different roads, all with different residence times, some may be year long, some day long, some century long, and some fractions of a second long, but until the energy leaves the atmosphere, it is all still all there is it not?

“This is why the warmists want to be able to claim the increased co2 level will cause the ocean to warm. It gives them more ‘residence time’ for extra energy trapped in Earth’s climate, and potentially explains a big ‘lag’ between the additional forcing and the manifestation of the energy in higher surface temperature.”

I think they must be desparate for this. If the primary effect of additional CO2 is to simply warm the atmosphere and use that energy to speed up the hydrologic cycle their theory is probably DOA. Do the models assume that the DWLWR heats the ocean as easily as an W/m2 equivalant SWR would? I certainly hope not, but I guess we never recieved the requested engineer style report on all that goes into the models.

75. tallbloke says:

but until the energy leaves the atmosphere, it is all still all there is it not?

Yes. When the ocean loses energy, it loses it into the atmosphere. When the atmosphere loses energy it is losing it to space, and has left the system. What I was getting at was that some of the energy input while the cars are on the long road will already have made it’s way out of the system by the time the cars reach the end of the road. Time is the extra factor.

Do the models assume that the DWLWR heats the ocean as easily as an W/m2 equivalant SWR would?

Very good question. I don’t know the answer. The modelers seem to assume that the ‘forcing’ from co2 slows the release of energy from the ocean. But they also assume a positive water vapour feedback, which they claim is vaidated by more recent satellite measurements. Richard Lindzen and Roy Spencer disagree.

Water vapour manifest in various ways, and the cloud feedback is negative as far as Lindzen and Spencer can tell from satellite data. It has got cloudier since 1999, according to to a couple of independent methods of measuring albedo.

76. David says:

Regarding tallbloke says:
December 9, 2010 at 11:45 am
but until the energy leaves the atmosphere, it is all still all there is it not?

“Yes. When the ocean loses energy, it loses it into the atmosphere. When the atmosphere loses energy it is losing it to space, and has left the system. What I was getting at was that some of the energy input while the cars are on the long road will already have made it’s way out of the system by the time the cars reach the end of the road. Time is the extra factor”

Thank you for the clarification and I think it supports “David’s Law” (-; …which reads: At its most basic only two things can effect the energy content of any system in a radiative balance. Either a change in the input, or a change in the “residence time” of some aspect of those energies within the system.