Grete Post

None of the real science on this is in any way supporting the IPCC conclusions.

Arthur:

"It adds up. None of the real science on this is in any way contradicting the IPCC conclusions."

But, Arthur, it is NOT adding up. Did you stop your observations in 1998, like many climate scientists seem to have done? Look at the CO2 increases vs. the temp DECREASES in the last few years. No "hot spots" in the atmosphere, like the GCMs predict. The models are completely out of line with reality, even though Santer, et. al. truncated the data in a desperate attempt to show the data fit the models (and they barely make the grade even with the truncation). The FACTS/OBSERVATIONS are contradicting the critical IPCC "scientific" conclusions (i.e., the weasel-worded crap such as "we are 90% confident that such and such is true...") . If you need something to fear, fear cooling; it would be much worse than warming.

A penny fee has virtually no effect on any commercial transaction. Give me a penny for each one then, since it has "virtually no effect" just as the GHE on a local level. What's wrong with your picture of the problem? Small effects at the local level, if they all add up in the same direction, can produce huge effects on a global scale. That additional 0.01% CO2 (and the additional water vapor it results in, which I thought was the whole point of your question) always adds its extra penny everywhere, uniformly, night and day. It adds up. None of the real science on this is in any way contradicting the IPCC conclusions.

Arthur: Bingo. Virtually no effect. So you think you will have a measurable effect on the Earth by adding 0.01% CO2? And you forgot to add IPCC's "positive water vapor feedback." Where is it demonstrated?

Jae (#105) - I've given you the answer on this before, but you continue to refuse to do the numbers. When you say:

I submit that the radiative effects should be nearly instantaneous, and by 1:00 pm on a clear day, it should be much hotter in the humid areas, if the radiative effects of GHGs work as advertised.

the question here is a quadruplying of H2O, which, if similar to the effect of doubling CO2 twice, would lead to an additional 8 W/m^2 of input energy. This compares to the 1000 W/m^2 coming from the sun, subject to significant reductions depending on cloudiness. The additional 8 W/m^2 from the GHE is going to make essentially no difference to how hot things get in the middle of the day - it's a less than 1% effect. The much more important effects are the other differences between desert and humid areas: cloudiness itself, and differences in latent heat transport from the surface due to differing water evaporation rates. Both are well-known as cooling effects on the surface, no mystery there (and see the "lapse rate" and combined "water vapor + lapse rate" feedback numbers in IPCC AR4 WG1 section 8.6.2.3).

If you really want to compare the greenhouse effects of water vapor, find two locations on Earth that have identical average incoming solar energy to within less than 1% (including cloudiness) for the period you are looking at, and compare temperature profiles in detail: you should be able to see a very moderately slightly higher average temperature for the humid region than for the dry one. But it's not going to show up in 1 day's high.

jae
Valid points. And here's another to ponder! Talking about deserts, I was curious one day about CO2 measurements in desert environments which seemed to me to be better for baseline CO2 measurements than, say, the top of a volcano in the Pacific, and I happened on the FACE experiment in Nevada:
http://www.unlv.edu/Climate_Change_Research/NDF...
I'm just one of those people who likes to see raw data before it goes through the mincer. Anyway they've taken ambient CO2 levels there very accurately and carefully, several times a day, every day for 10 years, in a location with minimal sources of CO2 contamination (I'm sure they are very cautious about that). Now I don't see much of a trend in those 10 years. It now has similar values to Mauna Loa - but then it had those same values 10 years ago. Explanations? Is there a developing CO2 sink in the desert that can cope with all those hugely increasing emissions? Don't think so! Of course you could tease a trend out of all that data by a suitable filter. On the other hand you could rely on the bunny's theory of large numbers (there are easily enough numbers there) and state happily that there is no apparent background trend in that desert for the last 10 years. Of course, it's nowhere near the sea :-)

JamesG:

"My only comments would be that apparently it is the minimum temperatures increasing while the maximums are staying roughly the same. Net effect gives the increase in average temperature. So that makes the question a little ill-posed. You should ask if the humid area minimum temperatures are rising? If they are, then your question is answered. Also some deserts can get very cold at night. Presumably they their climate is due to a total lack of water vapor so there is no possible positive feedback there at all."

I was far too general in my post. Of course, deserts are defined only as areas with less than 5 inches/year of precipitation, and there are some at very high altitude and latitude, where temperatures are very low, especially at night. I was referring specifically the great low-elevation deserts around 30 N and 30 S. Latitude (the "horse latitudes"). The absolute humidity there rarely goes below 5 g/m^3, so there actually is a fairly high quantity of GHGs, even in the deserts. The absolute humidity in the humid tropical areas, on the other hand, is virtually always above 20 g/m^3, or at least 4 times as great as the deserts. So there is 4 times as much GHG in the humid tropics than there is in the deserts. What has always bothered me is that if there is any positive water vapor feedback or even an enhanced GHE because of the presence of additional GHGs, then the humid tropics should get much hotter in the day than the deserts. The reverse is true. The humid tropics don't get above 33 C; whereas it often gets above 50 C in those deserts. Some of the commenters on RC have replied that the GHE effect slowly accumulates through time, and is not instantaneous. But I submit that the radiative effects should be nearly instantaneous, and by 1:00 pm on a clear day, it should be much hotter in the humid areas, if the radiative effects of GHGs work as advertised. Now, I think the question is explained mostly by a tremendous NEGATIVE water vapor feedback in the humid areas, due to evaporation and convection. But I also think that there is also some optimum amount of GHGs, similar to what Miskolczi is saying.

Jae
My only comments would be that apparently it is the minimum temperatures increasing while the maximums are staying roughly the same. Net effect gives the increase in average temperature. So that makes the question a little ill-posed. You should ask if the humid area minimum temperatures are rising? If they are, then your question is answered. Also some deserts can get very cold at night. Presumably they their climate is due to a total lack of water vapor so there is no possible positive feedback there at all.

98 Nick
"No - quite serious. What are electronic amplifying devices? "

Overdive an amplifier, and you hit the limit of the power supplied rail voltages. Clipping occurs, square wave produced harmonics. Turn all the way up the volume control of your transistor radio.

Nonlinear devices act as mixers. even sub-harmonic generators. Turning the Solar light bulb on and off produces harmonics called weather effects.

James G:

"But the only point I made was to ask if the postulated amplifying feedback from additional water vapor (ok and clouds) demonstrably increases the GHG climate sensitivity from 1.1K to 3K - that is, without altering the raw data in accordance with any models. "

Perhaps someone could explain to me why temperatures never get above about 33 C in very humid areas (lots of GHGs); whereas they get much higher in deserts (low GHGs), where even the lows (night) in the warm seasons are almost as high as the highs in the tropics. If the greenhouse effect and water vapor-amplification really works as advertised, then the humid areas should be much hotter, no?

BTW. I'd recommend reading Lindzen's stuff directly - not via someone else's interpretation. He is, after all, the most qualified skeptic.

Arthur
You seem to be more certain about cloud feedback than either Soden or the IPCC. Soden was even surprised that cloud feedback in most models was taken as net positive. There is a very good argument for net zero or net negative effect. No, I don't necessarily follow the IPCC classifications dealing with water vapor and clouds. Clearly they are very much related, since a cloud is formed by water vapor condensing on an aerosol particle. But the only point I made was to ask if the postulated amplifying feedback from additional water vapor (ok and clouds) demonstrably increases the GHG climate sensitivity from 1.1K to 3K - that is, without altering the raw data in accordance with any models. At this point, it doesn't matter where I look, the answer seems to be no! You'd think that to have such great confidence of dangerous climate change they could at least prove the idea that it all hinges on - the positive feedback. Because without that unproven assumption, there may very well be a temperature rise but not a dangerous or catastrophic one.

Not only that, but the models don't predict anything with any accuracy - something that is largely admitted. So if the models are of no practical use, the IPCC projections are of not much use. So what is your guess for 2100 temperature? And is that dangerous or catastrophic? And what specific data convinces you?

Nick #98

ere we have a large IR flux (235 W/m2) which can be varied with the operation of a small amount of heat evaporating water, which impedes the flow through its opacity. That clearly allows the possibility of power amplification.

you still have only 235 W/m2 flowing through (or less) there is nothing you can do to the earth system that will increase that short of getting rid of the atmosphere an the of course take the clouds with it. The higher temperatures that come from increasing impedance doesn't come with a higher power availability. If you are going to lift more water into the atmosphere you need more energy a lot more. Where is it coming from?

The transistors, FETs and thermionic valves cannot deliver more power than is available from the supply no matter what you do with the base, gate or grid.

No - quite serious. What are electronic amplifying devices? They have a large current flowing, which can be varied by the application of some much smaller power. A FET is probably the most analogous - you change the impedance of a channel with an applied voltage which requires negligible current and hence power.
Here we have a large IR flux (235 W/m2) which can be varied with the operation of a small amount of heat evaporating water, which impedes the flow through its opacity. That clearly allows the possibility of power amplification. If the effect of blocking the large flux is to create higher temperature which evaporates more water, that is positive feedback.

"Nick is just baiting ?"

I hope so.

Nick is just baiting ?
Or extrapolation modelling,
Amplification beyond power supply.
Filter capacitors can store only a little
But if you pull the plug on a hydro dam ?

Nick #94

Are you serious?

Jan #93
It isn't a passive system. The power source is sunlight. There's a flux of 235 W/m2 flowing through. Anything that can impede that flow can produce amplification and positive feedback. Just like a transistor or FET. Or thermionic valve.

Arthur #91

JamesG - yes, of course increased water vapor (positive feedback) is there for any source of warming.

Arthur would you care to show us how positive feedback is possible in a passive system? A passive system is one without an internal power source. You may on the other hand if you think the climate system has an internal energy source could you identify it for us please.

Those of us who are involved (or have been and I still have friends who are building plants) would really like to know how can run the plants without connecting to the grid a bit of positive feedback should make the efficiency better than 100%

Eric, model-of-global-warming thread, # 66, Nov 18, 2008 at 5:11 pm:

[KT1997's energy budget] is cited because the experts in the field find it useful. That is a good recommendation in my book, if I am unable to find the time to read it and evaluate it for myself. Of course one doesn’t take advice on things from people who are ignorant of a subject, no matter how many of them repeat the same thing. A cited reference is not the same as an old wives tale.

I have been meaning to get back to you on this. I was able to find the time and, to a limited extent, evaluate it for myself. And certainly, Miskolczi found a lot of time was able to evaluate it and provide some damning indictments that no one wants to acknowledge. Franko directed you to some of them, but you haven't commented. I have in the past directed the attention of Barton Paul Levenson to some of these, and he has consistently refused to comment; and right now, at ClimateAudit, Eli Rabett refuses to comment (on these points, and a number of others).

It seems you haven’t found the time to read it yet, so allow me to quote some of it. In KT1997, pp. 205-6, states (please read these quotes very carefully):

For the outgoing fluxes, the surface infrared radiation of 390 W m-2 corresponds to a blackbody emission at 15°C. Some of the radiation leaving the atmosphere originates near the earth’s surface and is transmitted relatively unimpeded through the atmosphere; this is the radiation from areas where is no cloud and that is present in the part of the spectrum known as the atmospheric window, taken here to be the wavelengths 8-12 mu m (Fig. 7).

But, why?

The Fig. 7 referred to here is the famous diagram of the KT1997 energy budget. All of it would contradict Miskolczi’s theory, if true, and show that Miskolczi is wrong. Indeed, this contradiction between M Theory and KT1997 is the primary reason adduced by Barton Paul Levenson for insisting that Miskolczi’s measurements are wrong (he also mentions that earlier budgets conflict with Miskolczi as well, but what does this prove? That even earlier, cruder budgets exist? And what about the fact that we’ve shown that some of the earlier budgets, e.g. the one given in Zagoni’s Hungarian textbook reference, as well as the budgets given in some of the MEP papers, seem much closer to Miskolczi than to KT1997? None of this gets a thought, or a mention).

KT1997 continues:

The estimate of the amount leaving via the atmospheric window is somewhat ad hoc. In the clear sky case, the radiation in the window amounts to 99 W m-2, while in the cloudy case the amount decreases to 80 W m-2, showing that there is considerable absorption and re-emission at wavelengths in the so-called window by clouds. The value assigned in Fig. 7 of 40 W m-2 is simply 38% of the clear sky case, corresponding to the observed cloudiness of about 62%.

Their estimate is – and you can see this for yourself – “ad hoc.” What does this mean? Some numbers follow that for all I can see have been pulled out of the air, before they arrive at their conclusion: “This emphasizes that very little radiation is actually transmitted directly to space as though the atmosphere were transparent.” Although they’re sure that some radiation is transmitted. Why?

Now Ferenc points out that these numbers aren’t even consistent with themselves. The clear transmitted flux density is supposed to be 99 * 38% = 37.6 Wm-2. So why say 38% and not 40.1%? Did they round off to the nearest 10 W m -2? Who knows?

How then can this guesswork be used as the basis for refuting the theory of Miskolczi?

In fairness, KT1997 go on to concede:

The values put forward in Fig. 7 are reasonable but clearly not exact.

Clearly, indeed. The question is, why? Accurate LBL codes are available now to compute the fluxes, and they were available in 1997. So why is the IPCC using guesswork instead of science?

But this isn’t even the biggest problem with KT1997, as you would have found if you’d followed Franko’s link.

Ferenc computed the average H2O amount in the USST76 atmosphere of KT1997, the NOAA atmospheres, and the TIGR atmospheres that he used in his studies.

http://climateaudit.org/phpBB3/download/file.ph...

Eli Rabbet is now complaining that there is not enough H2O in Miskolczi’s TIGR2 profiles. (Or is there too much H2O in the ‘corrected’ sets?) But that’s not all, having got the H2O levels far too low in the first place, they then reduce them by another 12%!

The ERBE data imply a global mean clear sky outgoing longwave flux of nearly 265 W m-2. This observation can be used to check the consistency of the assumed profile and the radiation model. Using the U.S. Standard Atmosphere, 1976 profile in the narrowband model yields a flux of 262 W m-2, surprisingly close to the observed flux. We reduce the standard atmosphere tropospheric specific humidity profile by 12% to ensure agreement between the model and observed global mean clear sky flux. The need to adjust the water vapor profile may be due in part to a bias in the longwave clear sky ERBE data (see Hartmann and Doelling 1991; Kiehl and Briegleb 1992).

Listen to this! “[S]urprisingly close to the observed flux!” Surprisingly? I don’t get it, they had to fudge the settings in their model, they concede the same, and then conclude “surprisingly close”? Is this a high-school science experiment or what is it? Can someone please tell me what’s going on?

**PS. apologies to be playing musical threads a bit but since the original thread has moved on to the virial theorem, this thread here seems to be the most appropriate home for this post. David, feel free to move it.

Arthur, 90:

"but Lindzen’s papers are referred to by IPCC and their main sources (Soden and Held, for instance) which I have read, and the feedback issues are pretty clearly delineated. Water vapor increase is coupled to lapse rate change, but those are pretty tightly constrained; there’s a lot of uncertainty still with cloud models, but even with clouds the net feedback is almost certainly positive and large enough to be second in importance (after water vapor + lapse rate)."

If the net feedback in all this is positive, the tropics should be much warmer than they are. The fact is that it rarely, if ever, gets over 33 C in highly humid areas. The "water vapor feedback" is a figment of pseudoscience. The problem with Soden and Held is that they go right back to computer models for their "data," IIRC.

JamesG - yes, of course increased water vapor (positive feedback) is there for any source of warming. That's why the IPCC breaks down the issues roughly into a forcing component (CO2, solar, volcanos, whatever) and a temperature response to that forcing, typically described as the sensitivity of the system to a doubling of CO2. That sensitivity is roughly a measure of the response of surface temperatures to *any* forcing of that magnitude, and includes all feedbacks, such as water vapor changes, cloud changes, lapse rate changes (the effect of water evaporation and condensation in particular) etc.

James - you seem to be confusing water vapor with clouds. Clouds are not water vapor, they are a separate component of the system, although of course they are a part of the water cycle. But water vapor can increase without having more clouds, there is no direct relationship. No, I have not read Lindzen's discussion of these things, but Lindzen's papers are referred to by IPCC and their main sources (Soden and Held, for instance) which I have read, and the feedback issues are pretty clearly delineated. Water vapor increase is coupled to lapse rate change, but those are pretty tightly constrained; there's a lot of uncertainty still with cloud models, but even with clouds the net feedback is almost certainly positive and large enough to be second in importance (after water vapor + lapse rate).

Geoff
Just to round out how odd Arthur's thinking can be at times, not only did he not know about the known and obvious cooling effects of the production of extra water vapor in the system (our own bodies cool by evaporation after all) - I just reread that he said this too:
"And the tropospheric hotspot is certainly not a specific consequence of water vapor as a GHG, since, as I said, it’s there in the models for any source of warming."
Thereby he somehow totally missed the rather obvious point that "any source of warming" would also produce the supposed water vapor positive feedback. If it's there for GHG's then it's there for solar. Svensmark argued this very point, so he hasn't read their papers either. Yet such ideas are actually quite basic. What is the point of physicists discussing higher level physics when they haven't quite grasped the basics?

#87 and others by JamesG

Your posts closely follow my observations and reasoning, which I hope you do not take as a kiss of death. Sometimes I wonder if it is nature or nurture which causes such strongly antogonistic posts even on a well-behaved blog like this. I suspect we had similar backgrounds. If so, they might even have demanded that we put our money where our mouths were.

sherro1@optusnet.com.au

Eric
The trouble with adjusting data because of supposed errors in the original is that these adjustments in the climate field always seem to enhance the overall warming. That's what raises the eyebrow of many of us who have ever collected data. Douglass et al. used data that were not adjusted and Santer et al. used data that were. That adjusted data hadn't been available to Douglass et al, but anyway Douglass later argued that these new adjustments were unphysical and so they stick by their original data selections. But since the adjustments are all based on models, it appears to be a circular argument of models verifying models. Hence the adjusted data is more a demonstration of faith that the models are more correct than the data, which seems to many of us to be entirely dogmatic.

Arthur
You don't seem to have read anything of what Richard Lindzen has published about feedback from extra water vapor I see. Any extra low-level clouds and extra evaporation are both cooling effects, hence negative feedback. So teh question is not even whether there is extra water vapor or not - it's whether the net effect of an increase would give a positive feedback which increases the climate sensitivity from 1.1K to 3K or is that just an overly pessimistic assumption. For that you need to examine the temperature data and the data tells you that it is a pessimistic assumption. This is Lindzen's main point. Hence it's not the physics which is already in the models that would make them miss the mark - it's the physics that were left out because the modelers assumed, apparently with little justification, that it wasn't important - albeit with the IPCC caveats that a) these are only best guesses, and b) a lot is yet unknown about the climate system.

And let's not leave out Lindzen's Iris effect which, you may have read somewhere had been debunked. In fact though it wasn't, and it has now even been backed up by observations. As an interested scientist I'd have thought you would at least have read some of Lindzen's arguments. He makes a very powerful case.

"In his reply to McCittrick,.."

When did Steve McIntrye morph/ merge into Ross McKitrick?

"Santer pointed out that McCittrick wasn’t concerned about the flagrant statistical errors in Douglas et. al."

This is known as changing the subject.

"I am not convinced that the end point is a big a deal as you claim."

Except that in an appendix to CCSP-SAP-1.1 report , Santer admitted that the choice of endpoint is a "big deal" because it could either underestimate or overestimate the underlying linear trend.

"Eric, you are getting into troll territory."

Actually, he is giving us a guided tour.

Eric,

Santer pointed out that McCittrick wasn’t concerned about the flagrant statistical errors in Douglas et. al.

No he didn't. He said:

you should be directing your attention to the 2007 IJoC paper published by David Douglass et al., which contains an egregious statistical error.

Which was also obviously wrong because he dealt with it at length on this web site. Eric, you are getting into troll territory. Try to be more accurate and not misquote please.

Eric:

"I am not convinced that the end point is a big a deal as you claim."

Read the post on ClimateAudit, and even you may be convinced that choice of endpoints is important. There was absolutely no excuse for Santer to cherry-pick his endpoint and ignore recent data. The study stinks because of this "game." Bad science.

"Dust ups with McCittrick are common."

A crusader against
Luboš Motl: " big scale organized crime"

Organized crime hides the records for it's protection
Criminal Climatists, hide the betting sheets for your own good ?

In his reply to McCittrick, Santer pointed out that McCittrick wasn't concerned about the flagrant statistical errors in Douglas et. al.

I am not convinced that the end point is a big a deal as you claim.

The paper pointed out that the interpretations of the remote sensing data are all over the map, and that the remote sensing data of the surface temperature has way more variation in the temperature trend that it measures, than the ground based records.

Dust ups with McCittrick are common.

# 78 proteus "Quite. Seems the left hand doesn’t know what the right hand is doing or doesn’t care."

Fraud and corruption are the causes of world poverty
Greenspan's fraud of US, by running the economy on debth
Another Fraud is the climatists' dogma

Indeed, David.

And did you notice the concluding quotation by Singer:

“Estimates of the linear trend are sensitive to points at the start or end of the data set…. For example, if we considered tropospheric data over 1979 through 1998, because of the unusual warmth in 1998 … the calculated trend may be an overestimate of the true underlying trend.”

This is found on page 130 of the CCSP-SAP-1.1 report (Karl et al 2006], in an Appendix, by Wigley, Santer, and Lanzante.

Quite. Seems the left hand doesn't know what the right hand is doing or doesn't care.

John Daly reported back in 1996 that a paper published in the journal "Nature" (Vol.382, 4 July 1996, p.39-46) by Ben Santer and others called "A Search For Human Influences On The Thermal Structure Of The Atmosphere" was trumpeted by as the final `proof' that Greenhouse was already here, proved not just by models, but also by actual observed data. (thanks to Michael Sirks). He reports this inspired the much quoted claim that there was "... a discernible human influence on global climate".

Alas it was not to be. Five months before `Nature' published two rebuttals from other climate scientists Prof Patrick Michaels and Dr Paul Knappenberger, both of the University of Virginia, who said:

"When we examine the period of record used by Santer et al. (1st graph) in the context of the longer period available from ref.5 (2nd graph), we find that in the region with the most significant warming (30-600 S. 850-300 hPa), the increase is largely an artefact of the time period chosen"

Santer had truncated almost 10 years of the most recent data to get his result!

Apparently he finds the lure of truncation is irresistable. In association with over 12 other authors, he again truncated the most recent results. Bringing the results up to date reverses the conclusion, that climate models diverge significantly from observational data.

Eric: Just where are you coming from, anyway? Are you a physical scientist? A political "scientist?" A liberal arts major? An NGO representative? A congressional staffer on the left side of the isle? WTF?

And note that he conveniently truncated his data at 1999. We've seen this crap several times in "climate science." Anyone who will not "come clean" with his data, methodologies, and responses to criticisms is not playing the science game. And it sure looks to me like there are precious few (naw , NONE) of the AGW-extremists who will play the science game fairly. Which casts a very dark shadow on their idea of "science." They automatically lose the battle, when they will not "come clean."

Eric:

"I suggest you read Santer et. al. to see what they really did."

I suggest you read ClimateAudit to see just what science is all about: http://www.climateaudit.org/?p=4314

71 cohenite // Nov 20, 2008 at 10:34 pm
said,

"Ah yes, Santer et al; I believe his ’study’, which found a THS, used model data which ended at 1998 and, “To facilitate the comparison of simulated and observed tropospheric temperature trends”, his study used a GLOBAL weighting function to reconstruct MSU cannel responses to find a TROPICAL effect, and concluded that the models would only be “incorrect” if the observations ( as manipulated by his weighting function) were roughly outside the 0.0 to 0.5C-per-decade window; which means that no warming whatsoever would NOT invalidate the models and the conclusion that there is a THS. Santer is a joke."

I suggest you read Santer et. al. to see what they really did.
https://publicaffairs.llnl.gov/news/news_releas...

The time period is 1979 to 1999 is used because there are a lot of data points and model results that can be compared to get a good statistical handle on the differences between model and data. This seems a good thing to do, since the purpose of the paper is to explore the extent of the differences between model and data. Do you mention this time period because there is something wrong with this idea?
I don't see where you get the idea that they inappropriately used a global weighting function on the data. The group used 7 different satellite/radio-sonde data bases from different researchers to compare with the models. There is no mention in the paper of any weighting analysis done on these data bases by the authors.

For the surface temperatures, they included 5 non remote sensing data bases for comparison, and the tight distribution of the trends found by this data stood out in contrast to the remote sensing data.

They compared the results of 49 different model runs on 19 different models .

They found a huge spread in the remote sensing data for the Temperature trend in degC/decade throughout all elevations. This reflected in part the difficulty of making and interpreting the measurements as well as the natural variation which makes it difficult to extract trends.
Natural variation accounts for a lot of the spread in the trends extracted from
the model runs, as well as differences in the models.

The paper shows that the remote sensing measurements need improvement in order to understand whether the models are right or wrong.
It also points out that the Douglas et al. paper, which concluded that the data falsified the models made 2 serious errors.
1) They didn't account for inter annual natural variability in the observed data.
2) They used an inappropriate metric to judge the statistical significance of the differences between models and data.
The paper is an excellent and thorough study. Far from a joke.

Trevor #70

“Black is Black” was written by by Tony Hayes and Steve Wadey and performed by Los Lobos. It reached #2 in the US in July 1966.

Mick Jagger and Keith Richard wrote “Paint it Black” and it was a hit for The Rolling Stones in 1966.

Of course - 42 your old memory tends to blur events like that.

Ah yes, Santer et al; I believe his 'study', which found a THS, used model data which ended at 1998 and, "To facilitate the comparison of simulated and observed tropospheric temperature trends", his study used a GLOBAL weighting function to reconstruct MSU cannel responses to find a TROPICAL effect, and concluded that the models would only be "incorrect" if the observations ( as manipulated by his weighting function) were roughly outside the 0.0 to 0.5C-per-decade window; which means that no warming whatsoever would NOT invalidate the models and the conclusion that there is a THS. Santer is a joke.

Relative Humidity at all levels;

http://www.friendsofscience.org/assets/document...

Specific Humidity at all levels;

http://wattsupwiththat.com/2008/06/21/a-window-...

In fairness to Arthur and his belief that atmospheric water vapor is increasing the SH is increasing at ground level and declining, markedly, higher up, which is consistent with M (ground cooling ie Spencer and Braswell, higher up more windows for the EU to depart), and the Dessler paper purports to find increased atmospheric water, contrary to the NOAA observations; but then Dessler is early days and still using a model.

Pedantic, I know, but precision and accuracy are important.

"Black is Black" was written by by Tony Hayes and Steve Wadey and performed by Los Lobos. It reached #2 in the US in July 1966.

Mick Jagger and Keith Richard wrote "Paint it Black" and it was a hit for The Rolling Stones in 1966.

Eric #64

Absorption and opacity are a function of band for a material. A material that is an absorber in one band can be transparent in another band. Glass is an example which we have just been discussing and the atmosphere is another.

What you have described here is something that is coloured and doesn't meet by any stretch of the imagination meet the definition of "black".

JamesG says,

"Arthur, the lack of a tropospheric hotspot shows that the postulated amplification of any warming (solar or GHG) due to water vapor positive feedback is overstated in the models."

There is no agreement about the lack of a tropospheric hot spot in the tropics.
Some data shows it, some does not.

http://www.realclimate.org/images/santer_etal08...
http://www.realclimate.org/index.php/archives/2...

JamesG says

the lack of a tropospheric hotspot shows that the postulated amplification of any warming (solar or GHG) due to water vapor positive feedback is overstated in the models

Why? Are you saying the models overstate the level of water vapor in the air? And yet observations (see IPCC AR4) seem to show increased water vapor in many different metrics; the tropospheric hotspot is hardly the only, or anywhere near the best, way to measure water vapor levels in the atmosphere. And the tropospheric hotspot is certainly not a specific consequence of water vapor as a GHG, since, as I said, it's there in the models for any source of warming.

But then you talk about the "negative feedbacks of increased water vapor" - which is it? Are you saying the models actually get the level of water vapor increase correct, but there's some "negative feedback of increased water vapor" that they are leaving out? What feedback is that? And what on earth does it have to do with the tropical troposphere?

Arthur, the lack of a tropospheric hotspot shows that the postulated amplification of any warming (solar or GHG) due to water vapor positive feedback is overstated in the models. That was the point Christy et al were making and it is the main skeptic criticism of the AGW case. As such it is still important. It has always been plausible that the thus far ignored negative feedbacks of increased water vapor countered the postulated positive feedbacks and that consequently the currently popular CO2 sensitivity is far too high. A lower CO2 sensitivity would actually reconcile the models with the obs with no data adjustments required. Attempts to either ignore this by talking about the stratosphere, or to undermine it by talking about model uncertainties or data adjustments just shows us that certain scientists like to fit the data around the theory.

For those of us not so worried about the effect of non-catastrophic warming on our future funding, what exactly is wrong with considering that the extra GHG effect has been exaggerated? The facts certainly fit that conclusion very well. Nor would it be the first time that a large collection of scientists have overblown a mild problem into something catastrophic. In fact it happens all the time. It even looks like the ozone depletion effects of CFC's were exaggerated too.

Eric asked

Do you have an estimate of the effective emissivity or the fraction of IR absorbed by a layer of air the height of a jar?

No better than yours - though it's possible you're underestimating a little because some wavelengths are more strongly absorbed than others, so that portion of the spectrum would be more fully absorbed in the height of a jar than you would expect from the average absorption of the whole atmosphere.

David says:

I think the relevant reference point is the ambient temperature.

But in your "model" post, you claimed this was testing Su = 3/2 OLR, i.e. the radiation leaving your "surface" - where you have the thermometer, is 1.5 times the total outgoing long-wave radiation from the system as a whole. Su is obviously determined by the temperature at the thermometer, but what is OLR for you here? You have given no clear reason why it should bear any relation to the ambient temperature, and you haven't tried to actually measure it.

We do know that the total energy leaving the system must be (in steady state) equal to the total incoming energy, per unit time. My approach above was to add up the total incoming energy, and assume that your system was sufficiently enclosed that the only way energy leaves is through radiation. That should give you pretty precisely the total OLR number, which is what you claim is the basis for T_blackbody. Can you explain why not? Why would OLR be so much lower than the total input energy? Where is the rest of that energy going?

Jan Pompe // Nov 20, 2008 at 5:17 am
said,
"Eric:
"You have to distinguish the between IR and visible light emissivity and opacity to understand the answer to your question."

Why? Black is Black even Mick Jagger understood that much."

Absorption and opacity are a function of band for a material. A material that is an absorber in one band can be transparent in another band. Glass is an example which we have just been discussing and the atmosphere is another.

Did you understand the rest of my explanation?

Arthur,
Do you have an estimate of the effective emissivity or the fraction of IR absorbed by a layer of air the height of a jar?
That would tell us the extent to which the air comes to equilibrium in the jar by means of radiation.

Pompe // Nov 20, 2008 at 5:15 am
said,
"Eric:
" Would that be at the equator?"

Why?"

Because the angle of the sun makes a difference in the illumination level.
Your formula solar intensity was correct only for the vertical incidence at the equator at noon.

Arthur, I think the relevant reference point is the ambient temperature. This was in response to you saying the increase wouldn't "be much". Look, how about we continue this after I release the results and my assessment of the general principle and I can be more specific then? I appreciate you making your assessement reasonably concrete.

<abbr>David Stockwells last blog post..Another American Thinker Walks</abbr>

You have to distinguish the between IR and visible light emissivity and opacity to understand the answer to your question.

Why? Black is Black even Mick Jagger understood that much.

Would that be at the equator?

Why?

David writes:

I have already shown the temperature at the sensor is over 30C above ambient with one jar, due to the greenhouse effect. So it can’t be T_blackbody.

Are you still claiming T_blackbody = the ambient temperature? That makes no sense - it's as if you are claiming that your local portion of Earth's surface is cooled only by radiation - you'll have jae up in arms!

To actually calculate T_blackbody (if by this term you mean the black-body temperature corresponding to a steady state with total outgoing radiation = total incoming radiation) you need to add up all the incoming radiation to your absorbing body. There are two main terms: short-wavelength (visible) energy from the sun, and long-wavelength (thermal) energy from the ambient environment (in particular, including "back-radiation" from the atmosphere).

That gives you a total number of incoming watts of power - then divide by the total emitting area of your absorber to get a W/m^2 number that should give you an appropriate temperature.

Ie. set S = incoming absorbed solar (per m^2), L = incoming absorbed thermal (per m^2), and f = fraction of your absorber/emitter that is exposed to sunlight (1/pi for a vertical cylinder with the sun shining horizontally, 1/2 for a flat surface that radiates on both sides, f = 1 is possible if you insulate the shadowed side properly). The total incoming radiation per m^2 of your absorber/emitter is:

total incoming = S * f + L

L should be close to the ambient temperature's black-body value, i.e. L approx sigma T_ambient^4. So T_blackbody for the system as a whole is simply:

T_blackbody = (S*f/sigma + T_ambient^4)^(1/4)

I.e. if S = 1000 W/m^2, f = 1/pi, and T_ambient = 36 C (309 K) that gives T_blackbody = 348 K or 75 C.

For f = 0.5 you get 366 K or 93 C, while f = 1.0 gives 404 K or 131 C. In principle achievable with this sort of set-up.

So the actual T_blackbody relevant for the problem here depends strongly on the geometry - whether your absorber is a cylinder, or flat, or has an insulated shadowed side.

Infrared absorption by the glass jars will partially decrease the net rate of outgoing radiative energy flow, raising the absorber temperature above T_blackbody (as long as other heat flows are also well blocked). Just knowing the glass jars' infrared emissivity isn't enough though to determine that effect: you need more of a temperature profile. Details of the geometry might help - what is the ratio between the glass jar surface area and the surface area of the central absorber/emitter?

an Pompe // Nov 19, 2008 at 9:59 pm

Dave #29

"Please don’t confuse me with Nick. I think the temperature in the single glass jar is already close to a maximum determined by the solar assuming 45% of of the radiation doesn’t make it to the surface on clear day then the “temperature” of the available radiation is \left( \frac {1370 \times .55}{\sigma} \right)^{\frac 1 4} \approx 66C"

Would that be at the equator?

Jan Pompe // Nov 20, 2008 at 1:35 am
said,
"Eric #44

"It takes almost the whole atmosphere to have an emissivity of 1. "

The whole of the atmosphere is a blackbody; is that why it’s so dark?"

You have to distinguish the between IR and visible light emissivity and opacity to understand the answer to your question.

The atmosphere is a "grey body" in the infra red band. If you had vision in the infra red, you would see the sky as light because the entire atmosphere above you us radiating in the IR band. It absorbs IR from the sun and earth's surface and re-emits it.

The atmosphere is almost transparent in the visible, so its emissivity is practically zero, but it does scatter some visible light from the sun, as a result of microscopic scale statistical fluctuations in density. These fluctuations change of the index of refraction in small volumes and cause blue light to be scattered. Without that scattering, except for the sun and stars the sky would be black in the daytime, because the sun and stars are the only source of visible light.

Outer space is black because there is no visible light coming from it.

50 jae said// Nov 20, 2008 at 1:39 am

"Eric:

“Thus, a real greenhouse does act like a blanket to prevent bubbles of warm air from being carried away from the surface”

This statement is one of my pet peeves. For crying out loud, blankets work PRIMARILY by blocking convection, just like the glass on a greenhouse. Folks that talk about “blankets” have no frigging clue of what they are talking about. And that includes one large chunk of the “climate science community,” it seems. Even our EPA has no clue, because they use the same type of terminology."

The use of the blanket analogy is fine if you are speaking to people who have no idea of what radiational cooling is. For that audience, you need to speak in generic terms of the earth's atmosphere as an insulating layer which prevents the escape of heat, analogous to a blanket that works to keep your body warm.

The outside of the blanket will be cooler than your body.
That crude analogy helps explain why it is significant that the stratosphere is cooler than the surface of the earth

This saves the trouble of introducing heat radiation, the stefan boltzmann equation all the other things involved, that most people have no idea about, because they never encountered them in their education.

Higher temperature, guessed from impeded convection. There is a certain distance between the jars that minimizes heat flow. Calculating temperatures along the way; looks like an iteration solution ?

Well, thinking some more, in light of David's brilliant experiment, I may have to recant some of my "beliefs." It does appear that the atmosphere is maybe effectively a "blanket" (glass dome?) over the planet. But it does not work in accordance with: meterology 101/KT 1997/IPCC/RealClimate/Nick/Arthur/Nick/Gore, etc.

Eric:

"This is meteorology 101. You should bone up on this stuff before you design experiments, but hey - live and learn."

It IS meterology 101. Sad, but true! :)

Eric:

"Thus, a real greenhouse does act like a blanket to prevent bubbles of warm air from being carried away from the surface"

This statement is one of my pet peeves. For crying out loud, blankets work PRIMARILY by blocking convection, just like the glass on a greenhouse. Folks that talk about "blankets" have no frigging clue of what they are talking about. And that includes one large chunk of the "climate science community," it seems. Even our EPA has no clue, because they use the same type of terminology.

Eric #44

It takes almost the whole atmosphere to have an emissivity of 1.

The whole of the atmosphere is a blackbody; is that why it's so dark?

cohenite // Nov 20, 2008 at 12:38 am

"Gee, G&T get the recognition they deserve at last, even if it is a backhander; teutonic rambling and ponderous numeracy; Nick you’re a crack-up! But G&T and greenhouses are a bit different from this experiment; this is a layered experiment as AGW views the atmosphere, with layers of aborbing barriers of CO2 between the surface and the eventual/semi-infinite, vertically ascending CEL or OLR or photosphere, or whatever you you want to call the area where temprature drops sufficiently for the emissions to leave. I’m not up to scratch with the maths so I’ll have to gut feel; if AGW is even remotely right it has to increase; if M is right then stay the same (although I would like some gradations in increase here to account for the logarithmic decline thingy) and if decrease then ice-age here we come. So I’ll say stay the same."

Sorry but the jar is an agricultural greenhouse. The influence of radiation absorption properties are irrelevant. The question is are 2 layers of glass better than one for an agricultural greenhouse, which suppresses loss of heat from the convection of air. The answer is an increase in temperature, if the solar radiation is not impeded from entering the double walls of the jar.
The black thermometer will convert this to heat, as will the bottom of the vessel which is in contact with the air.
Since the impedance to heat flow out of the space is impeded by the double walls of the glass the temperature should increase on the inside.
The emissivity of the air is so small, it has no impact on the flow of radiation through the space in the jar.
The convection currents will be set up in the jar if there are differences in temperature between the solid objects in the experiment, ie the walls of the jar, the thermometer and the base.
Because of the different values for absorption of solar radiation and emissivities there should be differences in temperature.
Just think of your car with a black dashboard, different colored seats and the the glass. All come to different temperatures when the sun shines on them.
These temperatures do not ever even out as long as the solar radiation is entering and shining at different angles on different materials.

I see you haven't voted yet Eric.

<abbr>David Stockwells last blog post..Another American Thinker Walks</abbr>

#42 jae

"Vote early, vote often"

I would be disappointed if someone did not try to stack the voting because an good scientist with an inquiring mind is forever saying "What if ...." Admin has a good mind too, fortunately.

Want to lay out $10 on the side?

Gee, G&T get the recognition they deserve at last, even if it is a backhander; teutonic rambling and ponderous numeracy; Nick you're a crack-up! But G&T and greenhouses are a bit different from this experiment; this is a layered experiment as AGW views the atmosphere, with layers of aborbing barriers of CO2 between the surface and the eventual/semi-infinite, vertically ascending CEL or OLR or photosphere, or whatever you you want to call the area where temprature drops sufficiently for the emissions to leave. I'm not up to scratch with the maths so I'll have to gut feel; if AGW is even remotely right it has to increase; if M is right then stay the same (although I would like some gradations in increase here to account for the logarithmic decline thingy) and if decrease then ice-age here we come. So I'll say stay the same.

Admin 29
// Nov 19, 2008 at 9:22 pm

"Eric:

"how do you determine the equilibrium temperature of the thermometer?"

By measurement, the maximum achieved temperatures, given that gusts of winds and clouds decrease the temperature significantly."

If the thermometer temperature is varying with winds and clouds and you choose a maximum, how do you know you have a stationary state? How can you compare 1 jar, with 2 jars unless you know you are getting the same radiation from the sun, ground, atmosphere and glass. Do you have 2 identical setups, one with 1 jar and one with 2 jars?

"Eric :
" The air will take up inside is a passive participant in this whole affair. "

The glass of the jar is the proxy for GHGs as IR absorbers."

That can't be right. The idea that the glass is proxy is totally wrong and backwards. The emissivity of the air in the jar
is the order of 0.0001. It takes almost the whole atmosphere to have an emissivity of 1 . There are not enough emitting molecules in a jar to absorb much of the radiation that is incident on it.

The emissivity of the glass is 0.84. The emissivity of the thermometer is probably 1 for solar radiation. The solid objects come to equilibrium with the radiation and drive the temperature in the jar.

Admin says,
Jan:
You say it is a test of understanding of the GH effect, but I don’t see any aspect of that here."

Its looks like a greenhouse, it behaves like a greenhouse, why is it not the greenhouse effect?"

The agricultural greenhouse effect is not the same as the atmospheric green house effect. I am surprised that you seem to be confusing the two.

http://www.ems.psu.edu/~fraser/Bad/BadGreenhous...

Does the atmosphere behave like a greenhouse?

"The name, greenhouse effect is unfortunate, for a real greenhouse does not behave as the atmosphere does. The primary mechanism keeping the air warm in a real greenhouse is the suppression of convection (the exchange of air between the inside and outside). Thus, a real greenhouse does act like a blanket to prevent bubbles of warm air from being carried away from the surface. As we have seen, this is not how the atmosphere keeps the Earth's surface warm. Indeed, the atmosphere facilitates rather than suppresses convection."

This is meteorology 101. You should bone up on this stuff before you design experiments, but hey - live and learn.

Nick:

"They conclude (sec 2.6):“It is not the “trapped” infrared radiation, which explains the warming phenomenon in a real greenhouse, but it is the suppression of air cooling.”

Yes. More correctly, suppression of convection. But convection is suppressed in our atmosphere, too--although it can sometimes go beyond the tropopause.

I tried to stuff the ballot box, like some folks do here in the USA, but it's too smart. :)

Time to vote. I say no change in temperature caused by the extra bottle. But I am far from confident.

Reason: With more mass between the heat source and the air inside the chamber, the heat flux entering the chamber will be lower initially. If we assume time exists to equilibrate, the glass walls will reach a steady temperature, the same as in the single bottle case by conduction, and there will be no cause for a change in outgoing heat. So no net change. (But I am worried by the properties of the interspace. If theoretically it was a perfect insulator, we would have a different experiment). It is not a simple concept overall.

David #29

Its looks like a greenhouse, it behaves like a greenhouse, why is it not the greenhouse effect?

David, I'll refer you to Gerlich and Tscheuschner, popular in sceptic circles (I got the link from Icecap). They ramble on teutonically for 20 pages proving that real greenhouses have nothing to do with the greenhouse effect. It's a strawman, but they're right. Ponderous but numerate. And they do not mention gas IR absorption in the greenhouse.

Incidentally they describe an experiment like yours (sec 2.4) but with a car. Temp outside 29C; in the car in the sun, 71C.

They conclude (sec 2.6):"It is not the “trapped” infrared radiation, which explains the warming phenomenon in a real greenhouse, but it is the suppression of air cooling."

"My humblest apologies Jan…"

That's OK I'm not offended I'm not sure about Nick though.

Your vote was for increases (see results link below). Do you want me to change it?

"What do you mean it went to unchanged?"

I thought the "unchanged" increased after i clicked on vote but I notice now that "increase" has gone up by one too could be timing then but if it did go to the wrong place it's entirely due to disobedient fingers this end.

Right or wrong, you won’t have a shred of credibility on this site if you don’t vote.

LOL.

I will post the results tomorrow afternoon US W Coast time. Right or wrong, you won't have a shred of credibility on this site if you don't vote. Cheers

My humblest apologies Jan... What do you mean it went to unchanged?

Oops it went to unchanged - Oh well so my guess was wrong and the incoming radiation loss is 55% and single jar case is already at maximum.

Oh, and:

F = OLR

Su - OLR = Ed -Eu, and probably all the rest of the clear-sky Miskolczi equations.

Dave #29

Please don't confuse me with Nick. I think the temperature in the single glass jar is already close to a maximum determined by the solar assuming 45% of of the radiation doesn't make it to the surface on clear day then the "temperature" of the available radiation is $$ \left( \frac {1370 \times .55}{\sigma} \right)^{\frac 1 4} \approx 66C $$

I expect a some improvement in insulation and the single layer is not quite a maximum if my guess of 45% of loss is correct so I'll go with a small increase. With less sensitivity to breezes.

25, admin:

Aa = Ed
Su = 3/2 OLR

Eric:

how do you determine the equilibrium temperature of the thermometer,

By measurement, the maximum achieved temperatures, given that gusts of winds and clouds decrease the temperature significantly.

The air will take up inside is a passive participant in this whole affair.

The glass of the jar is the proxy for GHGs as IR absorbers.

Jan:

You say it is a test of understanding of the GH effect, but I don’t see any aspect of that here.

Its looks like a greenhouse, it behaves like a greenhouse, why is it not the greenhouse effect?

David #23
My reasoning is simple - it's at about the level of whether an extra blanket keeps you warmer. There is heat flow in as sunlight, and heat flow out, predominantly as conduction/convection, with some IR, through the cover. If an added layer blocks the outflow more than the inflow, the temperature inside will rise. That last caveat depends on transparency. A black cover would cool.

You say it is a test of understanding of the GH effect, but I don't see any aspect of that here.

Sorry for syntax. In a hurry. Got to put up bookshelves for the wife.

Admin,
So if the sun is directly heating the thermometer, how do you determine the equilibrium temperature of the thermometer, and what does the air have to do with it.
All you are measuring is the heat transfer properties of the container fed by solar radiation and atmospheric downwelling radiation and the upwelling radiation it is absorbing from its surroundings. The air will take up inside is a passive participant in this whole affair. If the base on which the jar rests, the jar, and the thermometer case are heating up, their emissivity, and the geometry of the heat transfer problem determines the temperature distribution inside the chamber to first order. The air will move heat mainly by convection inside the container, and will take up a temperature profile determined by that. The fraction of the radiation that is bouncing around in the container absorbed by the air is miniscule and will not be a factor in the temperature measurement. Because the glass, the thermometer case, and the base on which the jar rests will try to come to different temperatures based on the reflected, transmitted and absorbed radiation the air between the bottom sides, top and the case will transport energy between them by convection to minimize the temperature difference between them as much as possible.

jae gets it. Care to propose a equation for relationship of the temperatures/radiations at equilibrium?

Nick says:

"3. A double coating of plastic reduces losses. Example statement:
“The insulation value is significantly increased when a second layer is added. For example, when double layers of plastic film are separated by a small air space, the result is an approximate 30% reduction in energy transfer compared to a single glass layer (Roberts and Mears, 1969).”

This is true, but I don't think it has anything to do with MAXIMUM temperatures during the day. It has to do with losses when the sun goes down.

Nick: So you don't feel misled when I present the results, I stress again we are talking about the maximum equilibrium temperature, not the temperature throughout daily operations. That is, I imagine a case on minimal convective loss, and maximum radiative loss, from the outside.

There is an industry study of real greenhouses here. It's emphasis is on covering materials. A few things they say:
1. Glass blocks most IR; plastic varies, half is possible. Using a material which blocks IR can save up to 13% of heat loss.
2. There is no mention at all of IR absorption by air in the GH
3. A double coating of plastic reduces losses. Example statement:
"The insulation value is significantly increased when a second layer is added. For example, when double layers of plastic film are separated by a small air space, the result is an approximate 30% reduction in energy transfer compared to a single glass layer (Roberts and Mears, 1969)."

That is right jae. If you were to plot the temperature across the apparatus, through the glass you would have something resembling a lapse rate. I have measured the outside glass temperature at about 48C when its 60C inside.

Eric:

"You phrase, “due to the greenhouse effect” is not obviously true.
How sure are you that your sensor is not being heated by solar radiation?
It has a black plastic case and is sitting in a sunlit glass jar."

Again, I think you are equating a thermometer sitting in the sun outdoors, where there is no thermal equilibrium between the thermometer and the air--with a situation where there IS thermal equilibrium (the air inside the greenhouse quickly equilibrates to the temperature of the thermometer, despite it being irradiated directly).

Eric:

"Explain how that equation applies to the air in the jar at ambient and 100% humidity and calculate the temperatures.
Compare them with my estimate of the magnitude."

I may not have this quite right, but here is my understanding. The glass "membrane" has essentially the same temperature as the ambient air (thermal equilibrium). Ambient is about 30 C, which is equivalent to 478 wm-2. The air inside is about 60 C, equivalent to 697 wm-2. 697/478 = 1.458, which is almost exactly the 3/2, showing that Su = 3/2 OLR for the greenhouse (the black line represents the temperature equivalent to the exact 3/2 radiation). I don’t think this is just a coincidence.

It appears that in a sense, the world actually does act much like the greenhouse. Both store heat and release as much as comes in at the cold boundary layer. Both have an IR absorbing layer and a blocking layer (convection only goes so high) around them and a cold boundary (picture the whole atmosphere as the glass wall in the greenhouse). The air temperature inside David's greenhouse is a measure of the total radiation from the surface, Su; whereas, the temperature of the thin walls is about equal to the ambient air, so you have a situation similar to Earth (picture all the “convection” going on inside the glass).

And notice that the presence of water vapor causes a little negative feedback in the whole process. Energy is invested in evaporating it, but some of that energy is returned to the boundary by condensation.

I think it is a brilliant experiment.

The apparatus is basically a greenhouse. It is being heated in the same way a greenhouse is heated. Why do you say its not a greenhouse effect is obviously not true? Of course the sensor is being heated by solar radiation.

The above post was directed to admin.

Ordinary glass blocks around 50% IR I saw somewhere. I have already shown the temperature at the sensor is over 30C above ambient with one jar, due to the greenhouse effect. So it can’t be T_blackbody.

Ordinary window glass has an emissivity of 0.84. That makes it a good absorber of IR.

You phrase, "due to the greenhouse effect" is not obviously true.
How sure are you that your sensor is not being heated by solar radiation?
It has a black plastic case and is sitting in a sunlit glass jar.

10 jae // Nov 19, 2008 at 5:19 pm

"Eric: I think you forget that this is an equilibrium situation. That’s different than an open-air situation."

This statement isn't clear.

My calculation used an situation in which we could neglect the influence of the characteristics of any jar walls and convection, which would complicate a calculation of a temperature difference. I calculated the surface temperature difference at the bottom of the jar with the 2 different gas mixtures to
see what the surface temperature differences were at the base of the gas sample. I looked at how the steady state temperature would change with a change in air material properties, holding solar radiation constant.
I am assuming that the gas sample would change temperature in accordance with the change in temperature of the base.

If you have a better computation that comes up with a temperature difference which reflects the change in greenhouse gas concentration of such a sample, please tell us how many deg C you get.

Arthur:

If you block all other paths to heat exchange and block some of the radiative exchange as well (the glass is somewhat infrared absorbing, and the second layer does not thermalize with the first) then you can get above T_blackbody, but in this experimental setup, since you don’t have infrared absorbing/emitting layers obstructing heat exchange over a wide variety of temperatures the radiative increase won’t be much.

Ordinary glass blocks around 50% IR I saw somewhere. I have already shown the temperature at the sensor is over 30C above ambient with one jar, due to the greenhouse effect. So it can't be T_blackbody.

11 jae // Nov 19, 2008 at 5:21 pm

"Eric:

“In addition, I have not yet seen an estimate of the difference between the air temperatures in the jar, predicted by the standard theory and Miskolczi theories. A calculation of that should tell us whether the difference is detectable by your apparatus, against the background of the other imponderables in your apparatus. ”

Read the post again. Su = 3/2 OLR."

Explain how that equation applies to the air in the jar at ambient and 100% humidity and calculate the temperatures.
Compare them with my estimate of the magnitude.

Eric and Arthur: We are interested in large changes here: Is it 1, 1.5 or 2 times ambient? Tell us the equation or the physical principle you would use. Stop being evasive. They are just a clear glass preserving jars. There are no tricks.

Eric:

"In addition, I have not yet seen an estimate of the difference between the air temperatures in the jar, predicted by the standard theory and Miskolczi theories. A calculation of that should tell us whether the difference is detectable by your apparatus, against the background of the other imponderables in your apparatus. "

Read the post again. Su = 3/2 OLR.

Eric: I think you forget that this is an equilibrium situation. That's different than an open-air situation.

Admin said,

"If you can’t predict the behavior of the toy, and explain the correct theory for the prediction, you shouldn’t be talking about the greenhouse in the atmosphere, IMHO."

The toy is a complicated entity. The radiative transmission and absorptive properties are not clear. The black plastic on the thermometer could heat up so much that the readings will not represent air temperature. You are supposed to keep thermometers out of the sun if you want to read air temperature. A climate sceptic should know that. The point has been made many times on Wattsupwiththat.

In addition, I have not yet seen an estimate of the difference between the air temperatures in the jar, predicted by the standard theory and Miskolczi theories. A calculation of that should tell us whether the difference is detectable by your apparatus, against the background of the other imponderables in your apparatus.

You claim 0.2C accuracy for your setup, and my estimate says the temperature change due to the standard GHG theory should be the order of 0.017C .

David, you can do the calculation for 36 C ambient as well as I can - isn't this blog about "the power of numeracy"? Numbers matter.

Yes, the principle here is quite different in that, unless your glass is strongly infrared absorbing (perhaps it is, as Geoff points out, we don't know the exact properties of your materials here!) you have not blocked the radiative path to heat exchange, while blocking latent heat, convection, and (through the double layer) most conduction.

If you block *all* paths to heat exchange, then the temperature is unlimited. If you block *all except radiation*, then the temperature is going to be limited by T_blackbody. If you block all other paths to heat exchange and block some of the radiative exchange as well (the glass is somewhat infrared absorbing, and the second layer does not thermalize with the first) then you can get above T_blackbody, but in this experimental setup, since you don't have infrared absorbing/emitting layers obstructing heat exchange over a wide variety of temperatures the radiative increase won't be much.

I would need to know the optical density of the new layer at different light wavelengths. If the glass is so transparent that it absorbs little light, then you get one answer. If it is opaque enough to heat itself, you will get another answer, such as, it will heat the interior. If it is opaque at some wavelenths and clear at others, then we start back down the yellow brick road of the conventional explanations. I would also need to know if the separation between the glass layers was large enough for the interspace to be an absorber. As a rider, an interesting additional measurement would be the temperature change in the interspace.

Arthur, So to clarify: Before you claim the temperature increase was unlimited using the principle at work raising the temperature of the earth about 33C above black body temperature. But you think the principle raising this apparatus about 33C above ambient is a different principle, which you think it is limited to roughly 2 times 3-400Wm2? You might want to do your calculations with an ambient of 36C too. Cheers

<abbr>David Stockwells last blog post..Greenhouse Quiz</abbr>

Ah, ok, you're implementing the better-insulated system. Well, I think I've already announced my opinion on the effect (it should reach a higher temperature, if there is any measurable change). However, I do wonder about the geometry here - you have a cylindrical surface absorbing the incoming sunlight? That cuts the ratio between incoming solar intensity and actual surface area by a factor of pi (pi * d circumference) assuming the sun is hitting the cylinder directly on its side. If the incoming solar intensity is 1000 W/m^2 and your ambient temperature is 20 C, that's a total averaged incoming radiating rate of 318 W/m^2 (from the sun) plus 418 W/m^2 (ambient) giving a true black-body number of about 64 C. So if you already achieved 60 C with one jar, 64 C is probably the limit with this geometry.

You could get higher temperatures with a flat absorber oriented to face the sun. It would probably be a worthwhile test to change the angle between absorber and sun (in the case of a flat absorber, that would be relatively easy to measure) and see how the maximum temperature changes.

But, once again, nothing to do with the atmospheric greenhouse effect.

No change. But it will cool off slower at night.

I assume that you meant another layer of transparent material on the outside (eg my suggestion of wrapping it in bubblewrap), and the maximum temperature is as measured by your sensor on the inside. So my vote is that the temp will rise, providing that the wrapping is transparent enough to sunlight.

I am not pretending to know anything. My vote is nothing more than a poorly educated guess.

<abbr>CoRevs last blog post..18 Nov 2008 Articles & Interesting Finds/Posts</abbr>

Another layer of what?