Guest Post by Willis Eschenbach
In my earlier post about climate models, “Zero Point Three Times The Forcing“, a commenter provided the breakthrough that allowed the analysis of the GISSE climate model as a black box. In a “black box” type of analysis, we know nothing but what goes into the box and what comes out. We don’t know what the black box is doing internally with the input that it has been given. Figure 1 shows the situation of a black box on a shelf in some laboratory.
Figure 1. The CCSM3 climate model seen as a black box, with only the inputs and outputs known.
A “black box” analysis may allow us to discover the “functional equivalent” of whatever might be going on inside the black box. In other words, we may be able to find a simple function that provides the same output as the black box. I thought it might be interesting if I explain how I went about doing this with the CCSM3 model.
First, I went and got the input variables. They are all in the form of “ncdf” files, a standard format that contains both data and metadata. I converted them to annual or monthly averages using the computer language “R”, and saved them as text files. I opened these in Excel, and collected them into one file. I have posted the data up here as an Excel spreadsheet.
Next, I needed the output. The simplest place to get it was the graphic located here. I digitized that data using a digitizing program (I use “GraphClick”, on a Mac computer).
My first procedure in this kind of exercise is to “normalize” or “standardize” the various datasets. This means to adjust each one so that the average is zero, and the standard deviation is one. I use the Excel function ‘STANDARDIZE” for this purpose. This allows me to see all of the data in a common size format. Figure 2 shows those results.
Figure 2. Standardized forcings used by the CCSM 3.0 climate model to hindcast the 20th century temperatures. Dark black line shows the temperature hindcast by the CCSM3 model.
Looking at that, I could see several things. First, the CO2 data has the same general shape as the sulfur, ozone, and methane (CH4) data. Next, the effects of the solar and volcano data were clearly visible in the temperature output signal. This led me to believe that the GHG data, along with the solar and the volcano data, would be enough to replicate the model’s temperature output.
And indeed, this proved to be the case. Using the Excel “Solver” function, I used the formula which (as mentioned above) had been developed through the analysis of the GISS model. This is:
T(n+1) = T(n)+λ ∆F(n+1) * (1- exp( -1 / τ )) + ΔT(n) exp( -1 / τ )
OK, now lets render this equation in English. It looks complex, but it’s not.
T(n) is pronounced “T sub n”. It is the temperature “T” at time “n”. So T sub n plus one, written as T(n+1), is the temperature during the following time period. In this case we’re using years, so it would be the next year’s temperature.
F is the forcing, in watts per square metre. This is the total of all of the forcings under consideration. The same time convention is followed, so F(n) means the forcing “F” in time period “n”.
Delta, or “∆”, means “the change in”. So ∆T(n) is the change in temperature since the previous period, or T(n) minus the previous temperature T(n-1). ∆F(n), correspondingly, is the change in forcing since the previous time period.
Lambda, or “λ”, is the climate sensitivity. And finally tau, or “τ”, is the lag time constant. The time constant establishes the amount of the lag in the response of the system to forcing. And finally, “exp (x)” means the number 2.71828 to the power of x.
So in English, this means that the temperature next year, or T(n+1), is equal to the temperature this year T(n), plus the immediate temperature increase due to the change in forcing λ F(n+1) * (1-exp( -1 / τ )), plus the lag term ΔT(n) exp( -1 / τ ) from the previous forcing. This lag term is necessary because the effects of the changes in forcing are not instantaneous.
Figure 3 shows the final result of that calculation. I used only a subset of the forcings, which were the greenhouse gases (GHGs), the solar, and the volcanic inputs. The size of the others is quite small in terms of forcing potential, so I neglected them in the calculation.
Figure 3. CCSM3 model functional equivalent equation, compared to actual CCSM3 output. The two are almost identical.
As with the GISSE model, we find that the CCSM3 model also slavishly follows the lagged input. The match once again is excellent, with a correlation of 0.995. The values for lambda and tau are also similar to those found during the GISSE investigation.
So what does all of this mean?
Well, the first thing it means is that, just as with the GISSE model, the output temperature of the CCSM3 model is functionally equivalent to a simple, one-line lagged linear transformation of the input forcings.
It also implies that, given that the GISSE and CCSM3 models function in the same way, it is very likely that we will find the same linear dependence of output on input in other climate models.
(Let me add in passing that the CCSM3 model does a very poor job of replicating the historical decline in temperatures from ~ 1945 to ~ 1975 … as did the GISSE model.)
Now, I suppose that if you think the temperature of the planet is simply a linear transformation of the input forcings plus some “natural variations”, those model results might seem reasonable, or at least theoretically sound.
Me, I find the idea of a linear connection between inputs and output in a complex, multiply interconnected, chaotic system like the climate to be a risible fantasy. It is not true of any other complex system that I know of. Why would climate be so simply and mechanistically predictable when other comparable systems are not?
This all highlights what I see as the basic misunderstanding of current climate science. The current climate paradigm, as exemplified by the models, is that the global temperature is a linear function of the forcings. I find this extremely unlikely, from both a theoretical and practical standpoint. This claim is the result of the bad mathematics that I have detailed in “The Cold Equations“. There, erroneous substitutions allow them to cancel everything out of the equation except forcing and temperature … which leads to the false claim that if forcing goes up, temperature must perforce follow in a linear, slavish manner.
As we can see from the failure of both the GISS and the CCSM3 models to replicate the post 1945 cooling, this claim of linearity between forcings and temperatures fails the real-world test as well as the test of common sense.
w.
TECHNICAL NOTES ON THE CONVERSION TO WATTS PER SQUARE METRE
Many of the forcings used by the CCSM3 model are given in units other than watts/square metre. Various conversions were used.
The CO2, CH4, NO2, CFC-11, and CFC-12 values were converted to w/m2 using the various formulas of Myhre as given in Table 3.
Solar forcing was converted to equivalent average forcing by dividing by 4.
The volcanic effect, which CCSM3 gives in total tonnes of mass ejected, has no standard conversion to W/m2. As a result we don’t know what volcanic forcing the CCSM3 model used. Accordingly, I first matched their data to the same W/m2 values as used by the GISSE model. I then adjusted the values iteratively to give the best fit, which resulted in the “Volcanic Adjustment” shown above in Figure 3.
[UPDATE] Steve McIntyre pointed out that I had not given the website for the forcing data. It is available here (registration required, a couple of gigabyte file).
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Ron Cram says:
May 15, 2011 at 6:56 pm
Tamino responds to me, not the other way ’round. Haven’t had any use for the man since about four years ago, not long after he started up he banned me from his site for my inconvenient facts …
w.
Hang on. You are saying it’s a ‘black box’ but you don’t make the effort of actually looking inside it. The GISS Model E GCM can be downloaded here. You can read the code yourself and it is documented. The box is actually completely transparent and comes with a manual!
The fact that you can do a curve fitting exercise to emulate one aspect of the model outputs in no way demonstrates that you understand how the model works and why it produces the results as it does.
And you have only done the curve fitting exercise on the average global temperature. The model simulates the global climate system – temperature, rainfall, pressure, snow ice etc., and the output includes the horizontal, vertical and temporal patterns of each.
Your effort is a pointless exercise in demonstrating that you don’t understand the model and have no interest in attempting to.
Steve McIntyre has posted up R code for the analysis I’ve done, at ClimateAudit.
The main issue for me is that the climate model isn’t adding anything. I mean, if you can forecast the future directly from the forcings, then there’s no value-added. A good model should give you something that you can’t get from a simple transformation of the inputs. It should add information to the mix.
But the GCMs don’t add anything new, they just spit the forcings out in a slightly different form.
Now, you could say that the model is valuable because it allows us to calculate the variables of lambda and tau … except that each model comes out with a different value of those two.
The main problem, however, is that we have nothing to show us that the underlying concept is true, that forcing actually controls temperature linearly. So that means that the different lambdas and taus we might get from the model may mean nothing at all …
w.
Craig Allen,
GISS couldn’t predict its way out of a wet paper bag. The endless “adjustments” it makes to putatively show that the planet is warming precipitously have been the subject of much debunking on WUWT. Here are a few of the many examples posted:
click1
click2
click3
Note that all of the massaged examples show greater warming, never less warming. What are the odds, eh?
Craig Allen says:
May 15, 2011 at 11:46 pm
Yes, I know that, I’m nowhere near as foolish as you assume. And I’ve read the manual and I understand what GISSE does … your point being?
Well, since I didn’t set out to “understand how the model works” or “why it produces the results”, all you’ve shown is that you don’t understand what a “black box analysis” really is.
Go away and rant elsewhere, please. I know much more than I want to about the GISSE model, I’ve been studying it for some years now, probing how they do things, asking hard questions of the programmers and getting little in return, and guess what?
Neither the GISS model, nor your babblings, have much in the way of scientific content.
Consider, for example, the way that the GISSE model handles water pools on melting sea ice … what’s that you say, Craig? You don’t know anything about how the GISSE model handles water pooling on melting sea ice? OK, then let’s discuss how the GISSE model doesn’t really balance, it just forces the books to balance energetically by simply adding or subtracting some energy … don’t know about that either?
My point exactly. Come back when you can explain to us why the GISSE method for handling melt pools is anti-scientific and discuss the problems with their methods for balancing the books… until then, my advice would be to just watch and learn.
w.
BLouis79 says:
May 15, 2011 at 8:48 pm
Postma’s claims make no sense at all. For example, he says:
Yes, in fact a black body does warm up if you reflect energy back onto it, that’s how the famous “space blanket” works in part … and so everything that follows is worthless.
BLouis, you might take a look at my posts called “The Steel Greenhouse” and “People Living In Glass Planets“. They discuss a number of the things that Postma misses.
w.
steven mosher says:
May 15, 2011 at 10:13 pm
Theo:
‘Explicate the model for the general public. ”
“If you want to know what a GCM does… READ THE CODE. The first time I looked at ModelE was 2007. Its not that hard or that long. get started.”
The simple-mindedness of this response is exceeded only by its condescending spirit. The code is part of the matter. Code contains heuristics that are understood only by advanced programmers who design the model and decide how to solve it. Otherwise, you are working with a tinker toy. No scientist has ever had the time to master such heuristics. What is really important and what we really want is the history of runs and the history of decisions made on the basis of those runs. Without that, we have no idea whether there is a rational process in place for using the model. A program run produces vast output, though this might not be known to the users, and that output has to be culled and interpreted. What I need to know is the rational process that is in place for doing the culling and interpreting. My guess is that there is none. Certainly, you seem to be unaware of it. I have seen nothing in publication by Warmista that would indicate that they are aware of it. Without such a rational process, specified on paper and regularly critiqued, all the model runs and all the model revisions amount to nothing more than rejiggering.
But to get back to basics, Shub Niggurath posted a beautiful little explanation of what it is to have a model that is not equivalent to a simple linear transformation on inputs. The model must use multiple terms (what I call predicates) and that list of terms must be irreducible. Do you know whether the models do this? I believe that you don’t have a clue what I am asking. If so, please say so.
Finally, there is the great frustration that sceptics experience whenever we challenge or question a Warmista, namely, the response is always “Figure it out yourself.” We want you to explain matters and to take positions on your explanation. This process involving all of us is supposed to be an argument, not a condescending teacher and his students. So, Warmista, stop acting like children, explain what you are doing, at least in response to legitimate challenges, such as Willis’, and, thereby, take responsibility for your work. So far, you have not taken responsibility for your work. You simply pretend to be above it all. Yet the fact of the matter is that you are out of it all.
Craig Allen says:
May 15, 2011 at 11:46 pm
“Hang on. You are saying it’s a ‘black box’ but you don’t make the effort of actually looking inside it. The GISS Model E GCM can be downloaded here. You can read the code yourself and it is documented. The box is actually completely transparent and comes with a manual!”
A typical Warmista response: “Figure it out yourself.” This is supposed to be a debate. After being challenged, Warmista are supposed to explain their position and defend it. We need their explanation so that we can criticize it. That is how science advances. Now, of course, Michael Mann and the Team pretend to have a new kind of scientific method where you never have to explain or defend your claims. Either they are pretending or they are the stupidest people now working in something called “science.” There is no alternative scientific method. When challenged, step up with your explanation and prepare to defend it. It does not work any other way.
Anyone who has ever tried a “space blanket” will attest that it does not retain heat as well as a real blanket. They are used as much because they are light/compact/cheap/disposable. Besides I already accept that insulation has no impact on a thermal *equilibrium* state because insulation does no work.
No doubt someone will do the blackbody reflector experiment in due course and a real answer will be known.
Personally, I find Postma’s explanations physically rational and useful. Further, if it is true that a large chunk of the reason for earth’s temperature is the radiative thermal equilibrium with the sun, it follows that the temperature of earth is highly sun-driven (others have said this) and that there is probably not a lot anyone on earth can do to modify it (over the dead bodies of the warmist believers).
So if Willis thinks it beyond the scope of all possibility that the combination of albedo effect (reflectance) and solar activity can explain earth’s temperature, then someone else will have to do the thermodynamic model run……
I question those forcing inputs at the outset. How were those arrived at? I’m not questioning your work Willis, I’m questioning however someone arrived at those forcings.
Volcanoes are a large net positive forcing? How is this? So the extra cloud creation from aerosol release is net positive?
Ozone is a large net negative forcing? Is this really the case? Most O3 loss is at one pole where direct sunlight is a rare luxury and ice blankets the continent 365 days of the year.
BLouis79:
Then, you’ve been “had”. As Willis points out, Postma is nonsense.
I’ll just go a little further in explaining why than Willis did. In particular, what is wrong with his lapse rate argument? The answer is that the basics of the picture are correct (and discussed in just about any elementary textbook on atmospheric physics or climate). Indeed, if you know the temperature at one point in the troposphere then you can use the lapse rate to determine the temperature at the surface.
However, what Postma would have you believe is that the effective radiating height is set by … well, he really doesn’t say but seems to suggest that you somehow just compute the average of the mass of the atmosphere or something like that. The truth of the matter is that the effective radiating height is determined by that level of the atmosphere where the “optical depth” ( http://en.wikipedia.org/wiki/Optical_depth ) of the atmosphere above is of order 1, so that most of the emitted radiation successfully escapes to space. (In reality, you have to consider an average because optical depth is a very strong function of wavelength due to the various absorption lines of the IR-active atmospheric constituents.) And that, of course, is determined by the make-up of the atmosphere, in particular, the substances in the atmosphere that absorb and emit mid- and far-IR radiation. (In particular, if the atmosphere was transparent to such radiation, then the effective radiating level would be the surface of the earth and hence it is the surface that would have to be at 255 K assuming the same earth-system albedo as we have now.)
So, Postma is right: Once you know the temperature at one level in the troposphere, you can use the lapse rate to get the temperature at the surface. The only problem is that the only way to get the temperature at a certain level of the atmosphere is to consider the greenhouse effect.
My guess is that Postma is smart enough to know this…which, if true, means he is engaging in active deception. Admittedly though, I could be wrong on this guess and it could be that he is deceiving himself too.
I had this exact same question, and I see you beat me to asking it. I did not see this addressed tho’. Willis?
Willis,
Nice post.
You note that both this GCM and the GISS model E fail to predict the actual 20th century temperature history, especially the ~1945 to ~1975 cooling trend. That failure stems (I suspect) from a combination of overstated sensitivity to forcing and the models not being able to simulate natural variation in the system. The most obvious natural variation is ENSO, but longer term natural oscillations like AMO, PDO, etc, which are not clearly understood, may explain most of the 1945 to 1975 cooling discrepancy.
Ron Dean says:
May 16, 2011 at 8:54 am
ian edmonds says:
May 14, 2011 at 5:24 pm
Sorry, I’d missed it above. Ian and Ron, you’re correct, I’ve fixed it in the head post.
w.
BLouis79 says:
May 16, 2011 at 6:45 am
I think nothing of the sort. What I do think is that Postma misunderstands the situation. I don’t know what his conclusions are, because his assumptions going in are incorrect, so I didn’t finish the paper. As you start your ideas above by “if it is true that”, it appears you have some of the same considerations … me, I don’t think his arguments hold weight. And if you thought about his claim (reflecting back the IR makes no difference either), and investigate it by taking it to an extreme, then you might not believe it either.
In any case, I gave you two references to explanations of why you were wrong. You come back and don’t comment on them at all, you just go on insisting that you are right. Do you see why people don’t like to engage in your kind of discussion. READ THE PAPERS. If you think they are wrong, tell us why. If you think they are right then Postma is wrong. Don’t just restate your position.
If Postma concludes it’s all solar plus albedo, more power to him. But getting the right answer in the wrong way got me no points in high school, and it’s the same out here.
w.
Jeremy says:
May 16, 2011 at 7:41 am
Jeremy, the values you are looking at in Figure 2 are not the actual forcings, but the observational measurements of the phenomena themselves. So for volcanos it is the actual mass of ejecta, and for ozone it is parts per billion by volume (ppbv).
As you point out, the volcanic forcing is negative (cooling the earth). However, the tonnes of mass ejected by the volcanos is a positive value.
w.
Joel Shore says:
May 16, 2011 at 8:33 am
Thanks, Joel. For those not familiar with the name, Joel is an AGW supporting physicist who is one of the few who are willing to brave the mud and storm and post here on WUWT. I give him big props for that. And while I may disagree with Joel over many things, his physics is good. In particular, his explanation of the Postma misunderstanding is excellent.
The problem with the Postma type of solution is that it says something like ‘Left to itself, the bottom of a planetary atmosphere without GHGs is constrained by physical principles to be warmer than the top.” This is perfectly true.
But then they then go a bridge too far and say “This shows that the bottom of the atmosphere is warmed by atmospheric processes”. Not true.
This is taking the stick by the wrong end. All that their true statement means is that whatever the temperature of the planetary surface might be, the top of the atmosphere will be cooler than the surface … in other words, the surface doesn’t warm at all from just the presence of a non-GHG containing atmosphere, but the top of the atmosphere ends up cooler than the bottom.
w.
Willis said:
“The current climate paradigm, as exemplified by the models, is that the global temperature is a linear function of the forcings. ”
…so, …the beginning and end of the ice ages should be a piece of cake to explain. ….uh. ….right? (insert sound of crickets chirping here)
When I input my data and run it through the equation provided, the answer is 42.
Willis Eschenbach says: “Yes, in fact a black body does warm up if you reflect energy back onto it, that’s how the famous “space blanket” works in part … and so everything that follows is worthless.”
A “space blanket” works by insulation. The fact you do not read any further smells of fear. If you have ANY body where its thermal emission is entirely reflected back onto itself, all that you will get is a standing EM wave pattern of energy flux density equal to the emission temperature. The temperature will not increase higher than the source temperature. At that point, the outside of the reflective surface will be emitting the thermal energy, because even the electric clouds in the atoms of a mirror are kinetically excited by photon impingement, which translates into thermal energy.
Joel Shore says: “The truth of the matter is that the effective radiating height is determined by that level of the atmosphere where the “optical depth” of the atmosphere above is of order 1, so that most of the emitted radiation successfully escapes to space.”
No disagreement. I’ll make this more clear in my next edit since it helps the case of reality so much.
Joel Shore says: “In reality, you have to consider an average because optical depth is a very strong function of wavelength due to the various absorption lines of the IR-active atmospheric constituents. And that, of course, is determined by the make-up of the atmosphere, in particular, the substances in the atmosphere that absorb and emit mid- and far-IR radiation.”
And because all of the O2 and N2, which make up 99% of the atmosphere, are radiating thermal IR, they weight by volume the average emission level to far above the ground. The N2 and O2 of the atmosphere emit the vast majority of mid and far IR radiation to space. You seem to imply it is only GHG which do so: you are incorrect.
“In particular, if the atmosphere was transparent to such radiation, then the effective radiating level would be the surface of the earth”
You must be one of the types who thinks only GHG’s emit thermal IR energy. ALL of the gases of the atmosphere emit thermal IR, and the N2 and O2 are thousands of times more prevalent than GHG’s. They also present their own “back-radiation” to the surface, but for some reason, are never included in how much warming effect this should have. This, when their ground-directed flux is thousands of times more prevalent than that from GHG’s. Interesting.
It is impossible for the radiating surface to be the ground surface of a planet if it has an atmosphere. ALL the gases of an atmosphere emit thermal IR, even if void of GHG’s, and this HAS to weight the average surface of emission off of the ground. And don’t forget, the true solar insolation temperature upon the earth surface is upwards of 100C, not -18C, as you’ve been led to believe.
“and hence it is the surface that would have to be at 255 K assuming the same earth-system albedo as we have now.”
Actually, you’d have to work very hard to actually find WHERE it was 255K on the surface. In truth, it would be a maximum of 87C (assuming albedo = 0.3), and a minimum determined by the heat capacity and rate of cooling at night, which is anyone’s guess. The total amount of actual Joules emitted would be equal to that incoming, but the energy flux density and related temperatures could be anything they wanted within that.
“The only problem is that the only way to get the temperature at a certain level of the atmosphere is to consider the greenhouse effect.”
Then why is it that the standard adiabatic material analysis gets the right answer without reference to GHG’s? It is because radiative transfer is INCLUDED in the materialistic adiabatic distribution. And don’t forget, ALL the molecules in the atmosphere emit thermal IR. Claiming only GHG’s do is incredibly naive. The temperature within the system can ONLY be determined by the input energy – the Sun. No passive component of the system can add more energy and increase its own temperature…come on this is so basic. And with an average of +30C insolation for the system, with a maximum of about 100C, there is more than enough solar input to sustain a ground temperature of +15C, especially when considering the additional adiabatic heating effects.
“My guess is that Postma is smart enough to know this…which, if true, means he is engaging in active deception.”
Nope…just writing about standard science and physics without referral to fiction.
Willis Eschenbach says: “Do you see why people don’t like to engage in your kind of discussion. READ THE PAPERS.”
Willis, please…just after you defend NOT reading my paper. The part you’re getting stuck at is actually only a very minor part of the paper. Even if I was wrong on that little issue, it actually has very little to do with the rest of the paper!
Equivocating between insulation vs. back-IR heating definitions becomes irrelevant when you understand the larger context of what I presented. There is NOT even a NEED to postulate a GH effect when you understand the the surface insolation is NOT equal to -18C. It is actually +30C for the system on the side which receives sunlight, with a maximum system temperature of ~100C under the zenith. The fact that it never actually gets this hot can only mean that the atmosphere cools the ground. The fact that the atmosphere IS cooler than the ground can only mean that it cools the ground. The laws of heat transfer apply equally to radiation as they do conduction. No object can conduct with itself to make itself hotter; no object can radiate with itself to raise its own temperature. Stop equivocating with sophisms related to insulation effects – the atmosphere is free to space.
“The problem with the Postma type of solution is that it says something like ‘Left to itself, the bottom of a planetary atmosphere without GHGs is constrained by physical principles to be warmer than the top.” This is perfectly true.”
And by obvious logical conclusion, the AVERAGE of the system has to be found in between. Therefore, the bottom of the atmosphere HAS to be warmer than the average.
“But then they then go a bridge too far and say “This shows that the bottom of the atmosphere is warmed by atmospheric processes”. Not true.”
That’s absurd. Venus doesn’t even absorb enough energy from the Sun in the first place to get to a surface temperature of ~700C, yet it does. Since this temperature CAN NOT be a result of radiative heating, since it doesn’t get that much radiation in the first place, it HAS to be a result of physical atmospheric processes. Radiation can not spontaneously amplify itself to a higher temperature potential…this is basic conservation of energy. Please neglect sophisms on magnifying lenses. There needs to be another source for the temperature increase on Venus…that source comes from physical processes in the atmosphere, such as and convection and adiabatic effects.
That’s the case on Venus. On Earth, the bottom of the atmosphere is heated by up to ~100C worth of solar insolation. Yet on Earth, the ground-air temperature is ALWAYS cooler than the maximum solar insolation. To increase the ground air temperature you need to increase the physical atmospheric depth and density.
Please read the entire paper at the website link .
BTW, I will be publishing a new paper in the coming weeks which completely supersedes ALL of this usual discussion on AGW and the GHE. What we’re discussing here won’t even matter anymore.
There are fundamental logical flaws in the the standard GH paradigm which, when exposed and explained in the way a stellar astrophysicist can, are seen to be so simple and so obvious that you wonder why you never saw it before. It will supersede the entire skeptic-alarmist paradigm…although the alarmists will lose the most. 🙂 I am sure the skeptics will love it once they understand the science…skeptics seem more prone to actual science.
@joel Shore says:”…you’ve been “had”. As Willis points out, Postma is nonsense.”
Well in the one corner we have physicists like Gerlich and Tscheuschner and Postma and Rancourt et al, in the other corner we have physicists like Joel Shore et al. It’s great to have a debate over physics. In the end, science will rule. Postma is was ahead on points for me. (Willis’s shells make not much sense, so don’t score points with me and I don’t see a lot of point arguing about scientific thought experiments that are untestable.)
I haven’t yet seen an AGW physicist propose a falsifiable proposition on the mechanism of the radiative “blanket” or “backradiation” theory that can be tested in the laboratory.
I have read discussions elsewhere on whether different gases can have different lapse rates without creating perpetual energy. Postma assumes that this is impossible and so the mean optical depth of the atmosphere is the point at which the temperature equals the mean surface temperature measurable from space using optical instruments. I find this reasonable. He shows this to be consistent with observed atmospheric and surface temperature data.
Perhaps Joel can tell me how an IR laser might be attenuated/scattered/reflected/thrown out of phase/delayed if directed through various gaseous environments? Can someone point me to papers on this??
BLouis79 says:
Don’t fool yourself. You can go other places on the web and see people debate if the earth is 6000 years old or not. The science has already ruled. G&T and Postma are just peddling pseudoscientific nonsense. Why do you think that people like Roy Spencer, Fred Singer, Richard Lindzen, and even Lord Monckton won’t endorse this nonsense?
That is a sad admission that you are incapable of distinguishing between real science and pseudo-scientific nonsense that you want to believe.
More nonsense. You can point a radiation detector up at the sky and detect the back-radiation. Satellites can look down from above the earth’s atmosphere and see the spectrum of radiation emitted. Furthermore, engineers use the same radiative transfer equations that scientists are using for the greenhouse effect in thousands of real world calculations.
What are you talking about? Who says different gases have different lapse rates. The molecules in the air rapidly thermalize. There are no different lapse rates.
I cannot figure out a way to parse this sentence that makes any sense. Do you undeerstand what “optical depth” means?
Of course his result is consistent! All that he has shown by this is that conservation of energy holds (i.e., that the earth / atmosphere system from space appears as a body emitting the amount of radiation that it must to be in radiative balance) and that the known lapse rate in the atmosphere holds. He hasn’t explained to you why the earth is only emitting this much radiation when its surface temperature is such that its surface emits much more. I.e., why does the earth look from space (sort of**) like it is a body with a temperature that is actually the temperature at some point 5 km above the ground? And, the reason that this discrepancy between what the surface emits and what the earth / atmosphere system as seen from space emits can be supported is because of the greenhouse effect.
You are being played for a fool by G&T and Postma. However, it is your decision to make whether you are going to show yourself to be such or whether you are going to show us that you can successfully distinguish between science and pseudoscience. From what you have said so far, I am not optimistic, but maybe you can pleasantly surprise us.
**[I say “sort of” because if you look at the complete spectrum of the radiation from the earth / atmosphere system, it is not simply radiating as a 255 K blackbody; it is only the total amount of radiation that corresponds.. The actual spectrum is dictated by the concentration and distribution of the IR-absorbing components in the atmosphere.]
By the way, BLouis79, can you explain to us how the paragraph that Willis quoted to you from Postma is consistent with conservation of energy? If the object is a blackbody, it must absorb the radiation reflected back. Where does the energy go if not into increasing the temperature of that body? Not only does Postma’s nonsense contradict experience, it also contradicts fundamental laws of physics!
And, you really want to admit that you are incapable of telling the difference between such nonsense and real science?
“The current climate paradigm, as exemplified by the models, is that the global temperature is a linear function of the forcings. ”
…so, …the beginning and end of the ice ages should be a piece of cake to explain. ….uh. ….right? (insert sound of crickets chirping here)”
Exactly. How could/can a predicted Maunder Minimum in 2100 (Abreu, 2010), in the context of more than 10,000 years of this interglacial already, become the beginning of the end of the Holocene and wipe out AGW?
Include Milankovitch as a forcing?
Why do the GCMs not include the indisputable major forcing mechanism of the last million years plus? Ignorance (after 1000s of papers)?
http://www.pages-igbp.org/download/docs/Steinhilber%20and%20Beer_2011-1%285-6%29.pdf
Gary Swift says:
In terms of the relationship between forcings (mainly changes in albedo and greenhouse gas concentrations) and temperature: yes, quite impressively. See http://arxiv.org/abs/1105.1140 (Fig. 4).
The basics of the timing of these changes in terms of Milankovitch osccilations leading to the buildup or melting of land ice is also largely understood, even if some details are still fuzzy. And, there are still some question about the exact mechanism that triggers the observed rise in the greenhouse gases, although again there is a rough understanding of why this would occur.