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Have American Thinker disproven global warming?

Posted on 22 February 2010 by John Cook

American Thinker have published an article The AGW Smoking Gun by Gary Thompson who claims to disprove a key component of anthropogenic global warming. The article begins by stating "...it seems that the only way to disprove the AGW hypothesis is to address problems with the science". This is a fair statement and a return to an emphasis on science in the climate debate is most welcome. So have American Thinker discovered a flaw in climate science that has escaped the attention of the world's climate scientists? Let's examine Thompson's article to find out.

Thompson looks at several peer-reviewed analyses examining satellite measurements of outgoing longwave radiation. As greenhouse gases increase in the atmosphere, they should trap more outgoing longwave radiation. This leads to a build-up of heat in our climate. It also means less longwave radiation escaping to space. The idea is explored in An observationally based energy balance for the Earth since 1950 (Murphy 2009) . Imagine this simplified thought experiment. The earth is in energy balance - incoming sunlight equals Outgoing Longwave Radiation (OLR). There's a sudden increase in CO2. OLR suddenly drops and the planet is in positive energy imbalance. The planet accumulates heat. A hotter object radiates more energy so OLR increases. Eventually OLR increases to the point where it again matches incoming sunlight and the planet is in equilibrium.  

Thompson looks at the several papers that compare satellite measurements from the 1970s to 1996 and later. The first paper that performed this analysis was Harries 2001. Thompson posts a graph from that paper that compares outgoing longwave radiation over the central Pacific from the 1970s to 1996. The black line is the outgoing longwave spectrum in 1970. The grey line is the outgoing spectrum in 1996.

IMG vs IRIS satellite measurements of outgoing longwave radiation
Figure 1: Observed IRIS and IMG clear sky brightness temperature spectra for the central Pacific (Harries 2001).

Thompson concludes "After analyzing this graph, the following conclusion can be drawn: The 1997 OLR associated with CO2 is identical to that in 1970". By "analyzing this graph", he presumably means eyeballing the graph as he provides no actual data analysis. This is a shame because in Harries 2001 directly below this graph is data analysis of the calculated difference between the IMG and IRIS satellite data as well as a comparison with modelled results. What do models predict will happen with rising greenhouse gases? Less longwave radiation will escape at the absorptive wavelengths of greenhouse gases such as carbon dioxide and methane. As the atmosphere warms, it will emit more radiation over the whole longwave spectrum. So we expect to see an increase in outgoing radiation over some of the longwave spectrum with sharp drops at certain wavelengths. This is indeed what is observed, consistent with model simulations.


Figure 2: Observed difference between 1970 to 1996 over the central Pacific (top). Simulated difference over the central Pacific (middle). Observed difference for 'near-global' - 60°N to 60°S (bottom) (Harries 2001).

The top curve in Figure 2 is the observed difference between 1970 and 1996 over the central Pacific. This shows strong agreement with the middle curve which is the modelled results. The bottom curve is the observed difference for a near-global area. Observations are consistent with our theoretical expectations of how the greenhouse effect should behave. The close match between observation and simulation lead the paper's authors to conclude "Our results provide direct experimental evidence for a significant increase in the Earth's greenhouse effect that is consistent with concerns over radiative forcing of climate". One wonders how Gary Thompson missed this conclusion as it's stated both in the paper's abstract and in the concluding paragraph.

There is much else that can be gleaned from Figure 2. Interestingly, the near-global observations show a greater drop in outgoing longwave radiation at the CO2 wavelengths around 700 cm-1 compared to the change over tropical regions. Does this indicate the change in greenhouse effect is greater at higher latitudes? It's also worth noting that the data doesn't cover the entire longwave spectrum as CO2 absorption below 700 cm-1 is not shown.

So what do we learn from the American Thinker article. Thompson cites peer-reviewed papers but his analysis consists of eyeballing graphs while spurning the peer-reviewed data analysis. This approach leads to the opposite conclusion of the papers' authors. I first encountered Harries 2001 when documenting the empirical evidence for an enhanced greenhouse effect. After reading the paper, I had many questions. Rather than let the gaps in my understanding lead me to think I knew more than the authors, I emailed my questions to the lead author John Harries, an approachable scientist who was forthcoming with prompt and detailed replies. The American Thinker article does not disprove the enhanced greenhouse effect. It does however provide further evidence for the Dunning-Kruger effect.

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Comments 51 to 84 out of 84:

  1. I just read the updated version with the disclaimer, which does make the all thing somewhat better. However, the paragraph following the disclaimer is still abusive: "So the results of three different peer-reviewed papers show that over a period of 36 years, there is no reduction of OLR emissions in wavelengths that CO2 absorb. Therefore, the AGW hypothesis is disproven." The first sentence is false. For any reader, the "results" of the papers is something that the papers actually contain, and would likely be assimilated with the conclusions of the papers. What would be correct for Thompson to say would be that the observational data contained in the papers suggest to him, without doing a data analysis, that there is no compelling change of OLR. Furthermore, the very fact that there is disagreement between the peer-reviewed conclusions of the papers and the non peer-reviewed conclusion of Thompson opinion piece should prevent the use of such definitive words as "disproven." I don't see how one can go at length to expose doubt, then jump to certitude. 2 questions for Thompson: 1-Did you also amend your blog post suggesting agreement between the researchers and you, which I will cite again here: (Posted by: gdthomp01 Feb 18, 03:07 PM) "But even on the wavelengths shown, there was no decrease in OLR at those wavelengths so I still felt comfortable drawing the conclusions I did - and the authors of these papers (using simulated results from climate models) drew those same conclusions using these wavelengths although they weren't based on the actual measurements." You say: " I still think this data isn't compelling enough to draw a conclusion about the OLR decreasing over the spectrum of CO2 absorption and I didn't change any of my conclusions because I still believe those." On what calculations/scientific assessment do you base these beliefs?
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  2. I will join Doug on giving kudos to John. That, and the strong focus on published science, is what makes this site among the very best on the subject.
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  3. Your article titled "Have American Thinker disproven global warming?" makes me wonder about grammar. Have the rules changed? Has the rule of noun-verb agreement changed? Isn't "The American Thinker" a singular noun requiring a singular verb? The American Thinker website thinks it does. You'll find this description there: "American Thinker is a daily internet publication...." So, if the American Thinker is a singular noun, your title--to be grammatically correct--must be "Has the American Thinker disproven global warming?" You made the same error in the opening sentence of the first paragraph and the next to the last sentence in that paragraph. What were you thinking?
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  4. robert test at 10:17 AM on 24 February, 2010 I'm guessing you're not from a Commonwealth of Nations locale. John is practicing King's English.
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  5. RE
    Response: Don't forget to post a review in iTunes :-)
    Just did.
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  6. King's English? Our monarch (long may she reign)is a Queen. Actually, 'American Thinker' as a collective noun may take a singular or plural verb. And long may we all think :-)!
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  7. I'd like to think that American thinkers are plural, even if I have my doubts about the magazine! Two nations separated by a common language, indeed. I commend Gary Thompson for coming here to discuss the issue politely, but Phillipe Chantreau's comments (#51) really are damning, and yet at the same time probably too kind. I don't see any defense for either sentence in that paragraph, nor is the rest of Thompson's analysis compelling. "My interpretation of data from three papers, which is not quantitative and is opposite to the interpretation of the authors, and in some cases not supported by actually doing the subtraction ..." would be a more accurate statement, I think.
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  8. Regarding post #51 - Philippe Chantreau - You say: " I still think this data isn't compelling enough to draw a conclusion about the OLR decreasing over the spectrum of CO2 absorption and I didn't change any of my conclusions because I still believe those." On what calculations/scientific assessment do you base these beliefs? " Fair question. let me see if i can do a good job of explaining. WARNING - I'm about to try and hyperlink references. not my strongest skill. if there is an issue, i'll follow up with another post with the links. and i apologize for the long post, it's hard to explain without graphics..... remember that I am arguing that there is no OLR delta between 2006 and 1970 over the regions where CO2 absorb and i feel the proof of that is fairly evident from the graph showing the delta but let's say I'm using "biased" eyes and in reality there is (on average) a -1K delta in Brightness Temperature (which could be argued from figure 5 in my article if you focused more on the lower wave nubmers/cm and ignored the higher wavenumber/cm portion that actually shows an increase in OLR). But let's assume that -1K delta and see what that equates to in W/m2 delta over 36 years. Once we get that difference of OLR flux let's plug that in the Radiative forxing X Climate sensitivity and see what temperature it predicts we should've seen. I'm going to do that by assuming calculating the W/m2 for an two ideal Blackbodies (that are radiating 1K different temperature) over all wavelengths to get the delta for the entire spectrum. Then, taking the ratio of that area under the blackbody curve which we are concerned with - the 700-780 wavenumber/cm and the other peak (which isn't shown on the data but we know is there - although it's OLR is less as we know from < a href="http://cimss.ssec.wisc.edu/goes/sndprf/spectra.gif" > here ) find out what proportion of the overall delta is associated with CO2 absorption. but first let's look at that ratio we are concerned with. As I noted in my post (#28) and as RC noted < a href="http://www.realclimate.org/index.php/archives/2007/08/the-co2-problem-in-6-easy-steps/" > here under Step 2, calculating the OLR flux from this data can't be calculated by hand. But let me try and simplify the situation and make it a worst case situation and see if that makes the calculations easier. As is noted on the RC post < a href="http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument-part-ii/" > here and the post on this page topic (#34 Riccardo) the CO2 absorption is saturated at and around the peak (15um) and all we are left with are these "spurious peaks". So these edges are all we'll be concerned with since the saturated delta will be zero. Next, pull up the graphs 3 and 4 in my article which correspond to the TES and IRIS measured data (2006 and 1970 respectively). you can see that they both roughly start around the 220K BT (for 700 waves/cm) and then rise to about 290K BT at around 780 waves/cm (which comprises the CO2 absorption range for the data in this paper). for the sake of estimating (and doing this by hand) let's treat that entire region as if it were a BT of 255K (in the middle of that linear rise). I realize this is an assumption but as I stated above, the other side of this absorption will be less so I feel I'm being conservative and biased toward the AGW position. Take a curve showing the radiation of a black body that is at 255K. plot that out and draw verical lines at 13.5um (750 waves/cm) and 17um (588 waves/cm), then shade that region of the curve in. that represents the wavelengths that are absorbed by CO2. If you ratio that integrated area to the total integrated area of that curve (over the entire wavelength range) you get around 21.5%. I'll be generous and even call it 22%. Notice also that the wavenumbers/cm shown in the three cited papers (starting at 700) represent the higher magnitude radiation on this 255K radiation curve (whose peak amplitutde is around 11um). If we assume at and around the 15um area that there is total absorption then let's say that portion that absorbs to extinction is half of the total inside that shaded region (and on the page of RC that talks about CO2 saturation that sounds conservative). So, half of this energy in the shaded region is what we'll use to calculate the W/m2 conversion from the data in the cited paper. so that 22% is now 11%. Let's use Stephan-Boltzman Law to find out what the delta OLR flux would be for two ideal black bodies who were separated by 1K (255 vs. 254K). taking 255^4 minus 254^4 and then multiplying that result by 5.67x10^-8 you get 3.74 W/m2. so the delta in energy from those ideal Blackbodies for all wavelengths was 3.74W/m2. but we are only interested in the part that CO2 absorbs and taking 11% of that yields 0.41 W/m2. so in 36 years we see a difference in OLR of 0.41 W/m2. Assuming 100% of that contributes to forcing attributed to GHG and using the climate sensitivity factor of 0.75C/(W/m2) which is also in the first RC link, you get a contribution of 0.31C in 36 years! so at best, using VERY conservative estimates (which i don't agree with) the OLR reductions contributed at worst 0.31C warming to the earth from 1970 to 2006. According to GISS trend map from 1970 to 2006 we've seen a warming of 0.73C. Even with my oversimplifications and estimates to skew the number higher, we see the predicted increase is less than half of the observed. and this is neglecting the net cooling forcing due to aerosols and natural changes which is 1.6 W/m2 (again, mentioned in the first RC post). If we deduct 1.6 W/m2 from the 3.74 W/m2 then we get 2.14 W/m2 and that takes the temperature delta down to 0.18C (after multiplying by 11% and 0.75C/W/m2). i'm interested in feedback on my method and math - PLEASE!
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  9. The number of TLAs in this thread is starting make it look like a military briefing.
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  10. typo in the spreadsheet carried over so a correction to the last few sentences of my previous post. From the RC link, 1.6W/m2 is not correct, the aerosols and natural changes is 0.9 W/m2 so that takes 3.74 W/m2 to 2.84 W/m2 and that equates to a temp increase of 0.23C. Sorry for the error, it's late here on the east coast of the USA.
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  11. A three letter Acronym.
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  12. Though I acknowledge their necessity, the first page of this thread looked rather impenetrable at first glance.
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  13. G Thompson: OK, I more or less follow you reasoning. I believe that it is overly simplistic, by far. At the top of the troposphere and above, CO2 produces cooling due to complex mechanisms that are related to the decreased IR reaching these levels as a result of the increased tropospheric CO2 at lower altitudes. Iacono and Clough did the work on this and Chen relies on Clough's updated radiative transfer model from 2005. All of this needs to be taken into consideration in order to determine if the upper troposheric OLR really correponds to expectations. The conclusion reached in the paper you used is that it does. Your calculations constitute a model, whether you realize it or not. I am not ready to give it more credence than LBLRTM or MODTRAN, both of which show radiative forcings at the surface far different from your back of the envelope model. I also believe that your model diverge from surface obervations of downwelling IR. I have no reference at this time but will provide some if I have the time (I have a life too). In any case, I doubt that the upper troposheric or TOA OLR can be used as a measure of the radiative forcing at the surface the way you did. This is no amateur work and it would be nice to have someone truly knowledgeable of atmospheric physics to help out (most of it is beyond me). I know that this is the stuff normally done with line by line radiative transfer models. The fact that the obervational data very closely matches the modeled results indicates that they've got it right. I will readily concede that some fine tuning may be needed on methane. The Griggs & Harries 2007 paper uses MODTRAN, and more observational data than the 2001 paper had, and the 2001 results are overall confirmed. The point is this: both of the papers you cited compare model results to observational data, in order to confirm that the models showing enhanced GH effect got the radiative transfer right at these higher altitudes. Both papers confirm that they did. Some details diverge, as anyone would expect. Obsevations exactly identical to model results would be suspicious. Your ending comment in the AT piece is thereby entirely unwarranted. BTW the Griggs and Harries 2007 paper can be found here: http://ams.allenpress.com/perlserv/?request=get-document&doi=10.1175%2FJCLI4204.1 And for Pete's sake, people, let's cut on the pedantic grammar remarks. They add nothing to the discussion. Are we going to look at typos next? Please...
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  14. garythompson, i hope that you (or anyone else) is not going to use these rather crude calculations to prove or disprove anything. In the response to John, Harries pointed out that one should be carfull in using brighteness instead of radiance: "to sum up all the energy you would have to use the radiance spectrum, not the brightness temperature spectrum. Though they are equivalent, the transform from one to the other is not linear. So, integrating brightness temperature would not be easy to interpret.". The average brightness, for example, is not the same as the average radiance. The correct calculation should be done with the full spectra as radiance, taking the non saturated part (which cannot be done with Harries spectra), calculating the difference and integrate. And even this is not accurate enough as, again, pointed out by Harries. It's rather odd that you think it is possible to disprove science made by professional scientists with a few hand calculations on numbers obtained drawing lines on a graph. At best you can get the order of magnitude, in this case not even that.
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  15. My understanding of the Earth's heat balance is that it will, in the long run, be a balance between heat energy reaching Earth from the Sun and the amount of OLR that the Earth emitting back into outer space. Granting for the sake of argument that there has been no reduction in the amount of OLR in recent decades, wouldn't that mean simply that the Earth had found a way to achieve balance in spite of the undeniable increases in atmospheric CO2? And the Earth has only one way to achieve balance given the CO2 buildup: by getting warmer. If this understanding is wrong, please help me out.
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  16. @garythomspon (#49), Nice try, and I do like your calm way you have elected to debate this, but I think your amended post on AT has a logical fallacy. You argue concerning the chart #3 that shows the 1907 & 1997 difference that "Since half the wavenumbers experienced a decrease and the other half experienced an increase, the data is not compelling enough to make conclusions either way with regard to OLR for these wavenumbers associated with CO2 absorption." What you are saying is that the curve of OLR differences averages out as 0 (approx.), so we must accept a Null Hypothesis that the difference between 1997 and 1970 is 0. First of all, the model curve also averages out as zero so should we not therefore accept the model as a valid prediction? But you are arguing that the model is wrong - hence the fallacy. Hardly a disproof of a key component of the theory of Global Warming. Further, IMHO, where you are going astray is that you are assuming a homogenous process underlying the curve. However, you can see the CO2, O3 & CH4 absorption bands highliged in grey. The question is - are the separate averages in the absorption bands for the three greenhouse gases significantly different from 0? Not sure about 02 and CH4, but the CO2 band seems to be, though I admit there is not a statistical test in the paper to demonstrate that conclusively. Certainly the model seems to be a good fit in the CO2 band. I think the authors are justified in claiming the following: "Changing spectral signatures in CH4, CO2, and H2O are observed, with the difference signal in the CO2 matching well between observations and modelled spectra.The methane signal is deeper for the observed difference spectrum than the modelled difference spectrum, but this is likely due to incorrect methane concentrations or temperature profiles from 1970. In the future, we plan to extend the analysis to more spatial and temporal regions, other models, and to cloudy cases. " This is good science - the authors publish their results through peer-review, are clearly concerned to establish the accuracy of their model, and clearly intend to do further work to verify their findings. Not the sort of people who deserve to be characterized as rogues and frauds, as your commenters on AT seem to believe.
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  17. the point i was trying to raise was - why do we need to correct for water vapor and surface temperatures when there are statements in peer reviewed papers that we don't need to do this in order to see the reduction in OLR associated with CO2 absorption? an example - according to the paper by Ramanathan entitled "Trace-Gas Greenhouse Effect and Global Warming" (http://www-ramanathan.ucsd.edu/RamAmbio.pdf), the author states on page 3 (which is really labeled page 189 since it was in a larger journal i guess) under the section Anthropogenic Enhancement of the Greenhouse Effect - "an increase in greenhouse gas such as CO2 will lead to a further reduction in OLR." notice there is no clarifying statement about having to use model simulated graphs to 'correct' for surface temperatures and water vapor before seeing that OLR reduction. and in the paragraph right above that the author states - "since the emission increases with temperature, the absorbed energy is much larger than the emitted energy, leading to a net trapping of longwave photons in the atmosphere." here the author stated clearly that even taking into account higher emissions from warmer surfaces, the net will still be a reduction. The Griggs and Harries - 2007 paper that Philippe Chantreau pasted a link to was great - thank you. i'm not all the way through it yet (and probably won't until several days the way this week is going....) but i did skim it and read the conclusions. here are a few quick takeaways that will probably get clarified or amplified once i've finished the paper. Fig. 4 showed the delta in OLR from 2003-1970 and again, i don't see how you can look at that graph and claim anything other than no change with regard to wavelengths in the CO2 absorption range. and with regard to the using the model to tease out the water vapor and sst changes - in the appendix the temperatures for 2003 were mostly equal to or lower than 1970 so that should've skewed the actual OLR measurements lower in 2003 (which it didn't). and in the conclusions the authors state that there is "perhaps a deficiency in the modeling due to aerosol or continuum effects." and in all three of the papers i cited in the article (and this new one listed above) the actual measured data show flat or increasing amounts of OLR which is in direct opposition to what AGW predicted in the Ramanathan paper. The simulated, modeled graphs (removing water vapor contributions and sst differences) show a reduction in OLR associated with CO2 absorption but again my whole take on this was to place more value in the real, actual measurements instead of the adjusted data. I understand what the authors (and many of you in your explanations provided here) are doing and why you are doing it and why the authors came to their conclusions (which are in direct opposition to the conclusion i came to in my article). we have a difference of opinion as to which data set has more value. that doesn't mean i'm calling the authors (or anyone here) frauds or degrading them or trying to discredit them. again, let me be clear, i have the utmost respect for the scientists who write these papers (as well as those on here whom i've conversed with) and i believe they are the tops in their field and would never do anything devious or underhanded to misrepresent data to help their argument. I think i've clarified that enough now. Philippe Chantreau - thanks also for your comments on my back of the envelope calculations - i didn't get to devote the time to digest all of your comments the way they deserve but i will. and i recognize the exercise is difficult but has anyone used the BT delta numbers (even the ones that were generated from the models removing SST and water vapor impacts) in these papers, converted that to what predicted temperature rise would be predicted for Earth (form say 1970 to 2006) and then compared that to GISS, HADCRUT3, etc. measurements? I would think this would be a valuable exercise. and contrary to a post (Riccardo #64) about me not even getting the order of magnitude right (which i did, 0.23 C and 0.73C are the same order of magnitude) my admittedly simple model led me to the conclusion that even a -1K BT delta isn't enough to validate the AGW model. i had to resort to that simple model because i couldn't find the calculation done but then again i don't have the extensive body of knowledge and connections that people here have - hence the reason for hanging out with you and the Real Climate blogs.
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  18. Gary, I'm not sure I agree with you (I'm huffing and puffing to catch up with all you heavy weights), but I want to thank you for discussing this issue like a gentleman. If only more blogs about this critical topic were conducted in this grown-up style!
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  19. @garythompson, I think you have shifted ground, but are not really getting anywhere. Quick explanation from www.realclimate.org: "The way the greenhouse effect really works is that adding CO2 reduces the infrared out the top of the atmosphere, which means the planet receives more solar energy than it is getting rid of as infrared out the top. The only way to bring the system back into balance is for the whole troposphere to warm up. It is the corresponding warming of the low level air that drags the surface temperature along with it ..... " Ok, so we would expect a reduction in OLR over the absorption CO2 range. It seems to be that is visible in ALL the papers under discussion. There is also excellent agreement between observations and the models. Let me draw your attention to Fig. 5 of the Griggs & Herries (1996) paper - this also plots the differences, but bands of statistical significance from 0 are marked with vertical grey bars. You can see a good collection around the 700-800 cm^-1 (CO2)region. This seems to me to put paid to the idea that the 1997 & 1970 observations are the same. Your fallback position is that the base models are somehow mistaken. As I pointed out, the models agree with the observations. You agree with the observations, so how can you challenge the models? Incidentally, climatology could not proceed without models, not could a lot of physical science (astrophysics, nuclear physics, to name two branches). Remember the old adage of the philosophy of science "All observations are theory-laden"? You need to toss aside your ideological blinkers. I agree with Ricardo that "Your ending comment in the AT piece is thereby entirely unwarranted." The only fallback seems to be Lindzen & Choi (2009) but that has already been thoroughly critiqued elsewhere http://www.realclimate.org/index.php/archives/2010/01/lindzen-and-choi-unraveled/
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  20. garythompson at 06:04 AM on 25 February, 2010 Gary, I think you're getting a bit lost trying to deal with comments while still leaving John's issues unaddressed. Could you go through John's remarks on your article point-by-point here, just so everybody's on the same page? Also, you should probably correct this sentence in the portion of your article where you discuss Lindzen & Choi 2009: "In the paper, the data showed that OLR increased when sea surface temperatures increased, so this is in direct contradiction to the AGW hypothesis that less OLR should be emitted since more CO2 is absorbing it and warming the planet." That's not really a sound conclusion, first because OLR increases in model predictions, secondly because Lindzen & Choi used undifferentiated OLR wavelengths thus making it impossible to discern C02 effects on the overall radiation, meaning you can't form a conclusion about C02 from their paper.
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  21. Gary, Following up Doug's comment: You (Gary) seem to be assuming there is a rule requiring constancy of the proportion of IR leaking out past CO2 in the CO2-absorbing wavelengths, versus leaking out in other wavelengths. Or maybe just that the amount leaking out in other wavelengths must remain constant while the amount leaking out in CO2-absorbing wavelengths decreases. There are no such rules. CO2 molecules bang into other molecules (both gas- and non-gas molecules), thereby transferring some of their energy. Also, CO2 molecules emit IR in directions that get it absorbed by non-gas molecules. All those other, non-CO2, energy-recipient molecules then go about their business, doing whatever they do with that energy, including transferring it to yet other molecules gaseous and non-gaseous. That energy is perfectly capable of eventually turning into IR in wavelengths that are not absorbed by CO2. Some of that IR will head out to space, unimpeded by CO2. In that way, IR that is blocked by CO2 can eventually work its way around the CO2 roadblock. Analogy: In a small stream (outgoing IR), put in the middle a rock (CO2) that is short enough to allow water to flow over it (IR leaking through CO2), but tall enough to noticeably impede the flow (IR absorbed by CO2). Ensure that the rock is not as wide as the entire stream (CO2 does not absorb all wavelengths of IR). Consequence 1: The amount of water flowing over the rock is less than the amount of water that was flowing in that exact rock-occupied area before the rock was there. Consequence 2: More water is flowing through the stream on either side of the rock. A second misconception seems to be that the only energy trying to escape from Earth at any given moment is the energy that came in from the Sun the moment before. The misconceived argument seems to be that consequently the amount of energy escaping cannot be larger than the amount of energy that came in literally moments before. But in fact, the amount of energy trying to escape depends on the amount of energy (well, heat energy--temperature) that is currently residing in the Earth's system. That resident amount of energy increases by accumulation due to blockage by CO2. In the stream analogy: If the rock in the middle is wide enough and tall enough, water will accumulate behind the rock. If the rock is really tall and nearly as wide as the stream, water will accumulate despite the increased flow at the edges. If you plop down a tall enough rock initially, or quickly create an equivalent pile of little rocks by plopping them down one at a time really fast, water will accumulate before the flow on the edges increases. That mass of accumulated water, not just the water coming from upstream, is what is now driving the amount of water flowing around the edges. So there is a lag between the accumulation and the increased edge flow. The exact consequences of how much water accumulates, how much flow increases at the edges, and how much flows over the rock, depends entirely and thoroughly on the exact details of the rock's height and width, the amount of water coming down the stream toward the rock, the obstructions at the edges, and so on. It gets even more complicated if you continually increase the height of your little dam by adding pebbles on top of it. In the Earth's system, the same things happen. The exact consequences--how much energy leaks out on either side of the CO2-absorbing wavelength bands--depend on the exact details of how much energy is coming in from the Sun, how fast CO2 is increasing, and so on. The bottom line is that it is perfectly feasible to have simultaneously, increased energy accumulation, increased outgoing energy at non-CO2 wavelengths, and decreased outgoing energy at CO2 wavelengths.
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  22. It is my understanding that OLR at the top of atmosphere mustn't be confused with the total long-wave radiation emitted by the whole Earth+atmosphere system. Conservation of energy dicrates that under steady state conditions the latter rather than the former must be equal to incoming solar radiation (minus reflected shortwave energy). So, when Ramanathan speaks of a reduction of OLR, he is not speaking of a reduction in the total longwave emitted to space that satellites measure. His Figure 1 also make that clear. Total longwave emissions include longwave from the surface that the atmosphere is transparent to. When greenhouse gasses trap more longwave radiation coming from below the top of atmosphere, then less OLR is emitted from there. But this is compensated when the surface heats up and more longwave from the surface escape through the 10-micron window (roughly). Under steady CO2 increase, as occurs now, steady state isn't achieved and there is a net energy imbalance of 4W/m^2 (also caused by water vapor feedback). This is much smaller than the total OLR reduction Ramanathan speaks of. Those are apples and oranges. Under steady state (no more CO2 variations), the 4W/m^2 imbalance would disappear but the constant large OLR reduction would keep the Earth from cooling back.
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  23. That's funny; it seems Tom Dayton and I said exactly the same thing at the same time, though in different words. OLR is the (reduced) flow just in wake of the rock. Total whortwave emitted to space is the total water flow downstream from the leaky 'rock-dam'. Conservation of mass dictates that this flow is equal to the flow (non-reflected solar input) upstream from the dam, except in the non-steady state where the water level rises upstream of the dam (heat accumulates and temperature therefore climbs below the atmospheric greenhouse-blanket)
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  24. Aha, Pierre-Normand! It was you that was that itch in the back of my brain while I was typing! I'm glad you wrote your version, because it is more technically accurate than mine. (I'm not technical.)
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  25. I just want to say that this thread has helped me understand some things that I not only didn't understand before but didn't realize that I didn't understand. Thanks!
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  26. Doug_Bostrom #70 - "Gary, I think you're getting a bit lost trying to deal with comments while still leaving John's issues unaddressed. Could you go through John's remarks on your article point-by-point here, just so everybody's on the same page?" i think that is an outstanding suggestion. Allow me a day or so to go through that and hit the bullet points and post something. i am no different that the rest of you on here in that i have a family and job that takes a higher priority so we all understand that this 'conversation' is a bit like one between an earthling and someone on Neptune. And i'm way out here, all alone on Neptune and i have 20 people on Earth sending me questions! but i'm not complaining, this is fun and i'm flattered that all here have willingly expended some of their valuable time in a conversation about this topic. i echo Ned's comments (#75) very frequently about the more you learn, the more you realize you didn't know. and that is what makes it fun. i also need time to, like Jesse Fell (#68) stated, to huff and puff through some of the exellent replies today. i would like to make this request though. in regard to John's article here and other postings here related to my A) apparent misrepresentation of the author's conclusions and B) leaving out graphs/data that is in opposition to my position. i feel i have clarified my position on those justified arguments in these posts, in my article revision and on the subsequent post on that article (in AT). i took full responsibility for that misconception due to my words in the article, apologized and i will not bother addressing those points either in John's article or posts here. remember that my article was written for American Thinker which is a blog which i also go to daily to get fresh takes on current topics and the editor's there thought my article was a fresh take that had not been put forth to a wide audience and they gave me that audience. for that i'm grateful and as an unpredicted consequence a fruitful conversation has sprung up here. it was an article expressing my opinion and i tried to support that opinion in the article and i am continuing to elaborate more on that in this forum which is better suited for the detailed science. it was an article, not a peer reviewed paper (although i seem to be getting plenty of that review now!). but i still want to get my position and facts right even though it is not a peer reviewed science paper. my name is on it and i wouldn't have written about that position if i didn't believe i was right. for the record, the peer review process is robust and i feel that is the right way to do things in science as long as the review is open, honest and unbiased toward the science. one more comment on the other half of your post Doug relating to the part of my article regarding Lindzen and Choi. of course you are correct that they evaluated the entire OLR spectrum and didn't have granularity into the spectrum that CO2 absorbs. let me explain why i made that statement in my paper. In Lindzen and Choi, the made the statement in the concluding remarks (section 3[14]) that ERBE differed significantly with models and showed that OLR increased with SST but the models showed it decreasing. And again, in the Ramanathan paper, he made the general statement that OLR would decrease with increased CO2 in the atmosphere. i could be reading too much into the Ramanathan paper but i feel that even the statement of Lindzen and Choi make my statement not incorrect. although, like you, i'd prefer to draw conclusions on CO2 by just looking at the spectrum that it absorbs. and one more point that is sort of on that topic and this was the main theme of why i wrote the article. from 1970 to 2006 the global temperatures rose by 0.73C and looking at the percent increase of IR using Stephan-Boltzmann i get a 1.02% increase (comparing 288K with 288.73K). by my estimates CO2 concentration went up 18% (from the mauna loa data). So shouldn't this much larger increase in CO2 have swamped out the increase in increase in overall OLR from the SST (which is the point i think Ramanathan was making in his paper)? I would've expected clear drops in OLR in the CO2 absorption spectrum even on the actual measured data even without compensating for SST. at best we are squinting and arguing over deltas that have values of 0 to -1K BT in the CO2 absorption spectrum. -1K of BT change equates to what with regard to predicted temperature increase? i don't know, my grossly simplistic calculation above is all i have to go on so that is why i'm here to ask the experts. ok, i'm sorry that is all i can respond to tonight but i'll plan to provide what you asked for later tomorrow night.
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  27. The SST temperature is an increase in surface temperature but the longwave energy (roughly 90%, if I recall) is being emitted from high in the stratosphere mostly in wavelengths that the atmosphere is opaque to. This emitting layer has cooled, not warmed. This is where the "swamping" occurs, because of the cooling that itself is the result of increased CO2 (and water vapor) concentration that shielded it from the warmer layers below. It needs not occur in the GHG bands only, as you seem to assume. And the total effect must be small if the system is close to being in radiative balance. Solar input did not vary (much), so neither does total emissions from both the top of the atmosphere and all the layers below.
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  28. In my post #72 I misstated Ramanathan's definition of OLR. The 'reduction' in OLR Ramanathan speaks of is conceived as the difference between longwave flux from the surface and total longwave flux from top of atmosphere (wherever this is being emitted from). With increased CO2 concentration, when steady state is achieved, the 'reduction' is larger than is was just because surface emission is larger. OLR does not change one bit, since it must still balance the same solar flux.
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  29. In taking Doug Bostrom's advice (#70), let me try and address John Cook's issues with my article one by one. i have gone through the article and attempted to summarize them into the following 3 categories: 1 - i misrepresented or missed the authors' conclusions in all three papers i cited. 2 - i was not forthcoming in showing all the graphs on those papers. 3 - i 'eyeballed' the graphs and there was no actual data analysis performed to reach my conclusions. as i stated before #1 and #2 has been addressed ad nauseum so i'll focus on #3. on the paper that John's article focused on (Harries 2001) he noted that i didn't include the second figure that showed the actual delta so i didn't have to "eyeball" it. in a previous post, i made my position known that even on the graph that John shows, the top graph, actual measured data, doesn't show a decline over the majority of the spectrum where OLR is absorbed by CO2. In fact, it appears that OLR has increased for most of that spectrum. To rectify this in my AT article i added the actual delta graph for the third paper and my commentary on that new graph is in the AT article and it follows the same line as my commentary in the pervious sentences. but back to the Harries 2001 paper, Figure 2 in John's article still shows, on average, that the CO2 absorption didn't decrease but rather oscillated around zero for the actual measured data. Minor point for John, I think the caption should read 1970 to 1997 (instead of 1996). once the models removed water vapor and SST, then the drop in CO2 was more pronounced. So, based on the data without model manipulation, i made my conclusions about this graph (which was my figure 2) that there was no change in OLR in the spectrum that is absorbed by CO2. I have stated before why i believe the SST and water vapor corrected graphs shouldn't have more value than the actual data (18% increase in CO2 vs. 1% increase in IR due to SST) but there is another reason i feel comfortable drawing that conclusion about Harries 2001. remember i had three papers cited in my article but we've only focused on #2 and #3. paper #1 also included harries as an author and the same time intervals (1970 vs. 1997) as Harries 2001. Since i don't have a membership to Nature i couldn't download the actual paper #2 cited in my article and it was the only one i didn't read. But paper #1 appears to have come first since it doesn't site other work by Harries on this dataset. i also think the difference is that Harries 2001 focused on the Central Pacific and this first paper i cite focused on the East and West Pacific. those who know the answer to this please correct me and fill in the gaps. anyway, please go take a look at that paper here (http://ams.confex.com/ams/pdfpapers/24874.pdf) and look at figures 1, 3 and 4. Figure 1 is actually 2 graphs showing delta BT measured for east and west pacific (1997 vs. 1970) and this corresponds to the figure 1 in my article. it's pretty obvious from this graph of raw data that the delta BT is at or above zero for the spectrum where CO2 absorbs (for both the East and West). It gets more interesting even when you bring in the model to compensate for temperatures and water vapor. on the top graph in figure 3 (east pacific) the delta BT is still at zero and i'd say it is above zero for most of that spectrum associated with CO2. the west pacific graph is shown in figure 4 (top graph) and again for the spectrum range associated with CO2 absorption there is no reduction in OLR. so i looked at all these graphs from paper #1 and #2 and concluded that CO2 is not decreasing in both of these papers and i can even make the case in the measured data in paper #1 that the OLR associated with CO2 absorption increased.
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  30. Gary, you wrote "according to the paper by Ramanathan...'an increase in greenhouse gas such as CO2 will lead to a further reduction in OLR.... Notice there is no clarifying statement about having to use model simulated graphs to 'correct' for surface temperatures and water vapor before seeing that OLR reduction." And you wrote "he made the general statement that OLR would decrease with increased CO2 in the atmosphere. i could be reading too much into the Ramanathan paper." Yes, Gary, you are reading far, far too much into that statement. That statement was made in a journal for climate scientists, who know perfectly well that the total effect on OLR depends on all the mechanisms that come into play when CO2 is increased, and on mechanisms independent of CO2 that come into play nonetheless concurrently. It is so well known that it need not be stated for that audience. Indeed, if the author had stated it, the editor probably would have insisted it be removed to shorten the article and reduce clutter. Professional journals are not like textbooks, Science News or Scientific American, let alone a newspaper or the American Thinker blog. Journals rarely need or want "clarifying statements" about rudimentary knowledge, unless the editors strongly expect that the audience will include substantial numbers of people outside the normal, professionally specialized, audience of that particular journal. What if the authors had tried to make a "clarifying statement"? Hmmm.... Given the complex set of variables involved in determining the precise amount of OLR in response to the CO2 increase, they would not have been able to give a single answer, because the answer varies across situations, depending on the precise details of the situation being predicted, and there is an infinite number of situations. Instead they would have to, let's see... construct a model that they and others could run separately for each situation. They and others also would use that same model as a component of models for predicting temperature responses to increased CO2. But responsible scientists would want to verify that model's OLR predictions against real world observations! They would have to run it, then show its results...say as a graph line...maybe displayed underneath a graph line of the observed OLR over the same time period. They might even label that graph Figure 1.b and c. Gary, nobody is taking issue with you for not knowing all that. You would have if you had spent significant time writing articles for professional scientific journals in any field, even as a mere grad student. But you don't have that experience, so no foul. What people are taking issue with, is your quick leap to very public and strong proclamation before investigating sufficiently. When faced with your own "obvious" conclusion that flies in the faces of thousands of professional, specialized scientists who have spent many decades researching that topic, the stronger your feeling of certainty is, the more you should suspect that you, not they, are missing a fundamental piece of knowledge. And the harder you should dig to verify your own conclusion. That's what I do. That's what John Cook does. That's what most of the commenters on this blog do. Sometimes (and sometimes often) we don't dig deep enough to verify our opinions, and so write a comment that is wrong. But we write a comment, not a whole, highly publicized blog post. And we usually prefix our comment with "I think I'm missing something, but it seems to me...," and other folks correct us. Often not gently. That difference between your behavior and our typical (not perfect) behavior is what the Dunning-Kruger effect is about.
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  31. Thanks to Tom Dayton for the reminders. I myself wrongly assumed that those spectra ought to be consistent with the fact that total OLR must (almost) balance solar input and hence not vary much. But while this must be true globally, the measured spectra aren't global averages. And the Earth doesn't warm uniformly, neither does the stratosphere cool uniformly. There should be no a priori expectation that total OLR flux in the observed area should behave the same as they do globally.
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  32. Gary, Good for you for responding to the comments. However, while you seem exceedingly humble, willing to learn and interested in constructive criticism, I feel these characteristics are in striking contrast to the tone in your article: "A key component of the scientific argument for anthropogenic global warming (AGW) has been disproven." Such hubris is astounding. I am wondering if you are going to the Comments section of American Thinker to defend the scientists that are being attacked regularly at that site and in the MSM of late. I hope you point out, not just your errors, but that such scientists have been remarkably responsive and helpful. Maybe, your penance should be, to review and criticize one of the newest pieces on American Thinker: http://www.americanthinker.com/2010/02/the_hidden_flaw_in_greenhouse.html I will skip to the conclusion of the article: " Either way, therefore, the convoluted theory we've been going by is wrong." In no way, am I qualified to review that article, but I expect that you think that you are. I hope this is not too off topic, but I am frustrated that every random AGW atack has to be officially debunked due to the political atmosphere. If you are going to be skeptical of scientific consensus, you should be skeptical of all scientific papers "published." thank you, milestone
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  33. Tom Dayton (71), You state (correctly): "The bottom line is that it is perfectly feasible to have simultaneously, increased energy accumulation, increased outgoing energy at non-CO2 wavelengths, and decreased outgoing energy at CO2 wavelengths." Would you agree that conservation of energy would mean that the decreasing outgoing energy at CO2 wavelengths cannot be fully responsible for this condition, but there must be an addition source of energy input? I am having a hard time wrapping my head around a small decrease in one part of the outgoing spectrum being responsible for a larger increase in other parts of the spectrum AND an increase in the energy stored in the system. (Riccardo - Thank you for a cogent response in 46.)
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  34. thanks again for John and all on here for allowing me to participate in this conversation. i have enjoyed it and i'm sure we'll bump into each other again on RC and SS and if there is something that sparks a question or comment you'll 'see' me. i do have three parting questions that are still on this topic that i have not received an answer to so i'd appreciate it if someone would either answer this or point me to a link that gets me to the answer. 1 - I put forth a rather simplistic model to try and correlate the delta BT to delta C. My rather simplistic model was dismissed and i have read on RC where it is a difficult calculation to do by hand and requires models. Has this been done? Even if i agree with you that all of these papers show a 1-2K drop in OLR emission in the 36 year period from 1970 to 2006, what temperature increase does that predict using the models/calcuations? it seems that would be a fairly important piece of information to 'close the loop' on this. for those who have cosmology/astronomy backgrounds i liken this to the cosmic microwave background radiation that validated the big bang theory. although there are still steady state people out there......skeptics die hard. anyway, delta k in BT is all nice but delta C/decade is what we are all concerned with. 2 - I still haven't heard any comments on the first paper i cited in the article (http://ams.confex.com/ams/pdfpapers/24874.pdf). even with removing the effects of temperature and water vapor the OLR spectrum related to absorption by CO2 didn't show a reduction. 3 - The Griggs and Harries 2007 paper (http://ams.allenpress.com/perlserv/?request=get-document&doi=10.1175%2FJCLI4204.1) has an interesting component to the 1997-1970 central pacific data set. there is a large spike down (~5k) in the measured difference spectra on page 3989. The authors give a suggested explanation of that and even allude to a channel issue but this is the same data that is in the Harries 2001 paper and that paper does not show this spike. why the difference?
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  35. Gary, regarding your question "1," your phrasing "it is a difficult calculation to do by hand and requires models" might just have been casual phrasing, but then again might reflect a misunderstanding. Calculations by hand also involve models. I'm guessing you do in fact know that, because your first sentence was "I put forth a rather simplistic model." But to audiences such as the usual readers of American Thinker, your "requires models" phrasing might well be misunderstood.
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  36. @garythompson, "i do have three parting questions that are still on this topic that i have not received an answer.." Sounds to me like you haved decided to take your football and not play any more.... I did take a look at the paper you mentioned in 2. I think Figure 1 should show you what you need. You did not respond to me suggestion that you review figure 5 of the Harries 20006 paper which clearly indicates the areas where the difference spectra are significantly different from 0. To me, those charts blow your conjecture out of the water. Now, I suggest you approach the editor of American Thinker and request that he publish a retraction of your article...
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  37. guinganbresil wrote "I am having a hard time wrapping my head around a small decrease in one part of the outgoing spectrum being responsible for a larger increase in other parts of the spectrum AND an increase in the energy stored in the system." You're right that (total in) must equal [ (total out) plus (accumulation) ]. But there is an infinite number of combinations of the values of those three terms, that satisfy that equation. The extra output can be merely slightly higher as long as the accumulation is sufficiently large to make up for that slightness. I'll now strain my stream analogy to the breaking point. When you add pebbles (CO2) to the middle of the stream, the water being held back does not immediately flow around the edges. Instead, there is a lag during which water accumulates. During that lag, the input is larger than the output, which looks like a violation of the equation until you remember that the equation must include the accumulation as well. Then the extra weight of the accumulated water increases the pressure on the stream's edges, and finally the outward flow at the stream's edges increases in response. The equation has been true during that entire process, but the exact values of the three terms have varied. But the extra flow at the edges is not enough to allow all the accumulation to escape. The only reason extra water flows there is because the extra pressure from the accumulation is enough to overcome the resistance at the edges. As extra water escapes, the accumulation decreases, the pressure decreases, and the flow at the edges decreases. But if the flow at the edges decreases too far, accumulation starts again, which increases the flow at the edges. It's a feedback that results in a new equilibrium of input, accumulation, and output. The time at which that new equilibrium is reached is "the long run." But even in the short run, the equation holds. For us to see that it holds, we must be measuring all the terms of the equation: input, output and accumulation. We can't look only at the input and output and expect the resulting impoverished equation to hold. And then while you are semi-methodically adding pebbles (CO2) to the pile in the middle of the stream, your playmates are randomly adding and subtracting pebbles at the edges of the stream. And your pile of pebbles is sitting on a big flat rock that is sitting on a pointy rock so that as you add pebbles the flat rock moves, thereby moving rocks at the edges of the stream, thereby changing the resistance at the edges of the stream. It all gets complicated enough that you need a model more complicated than mere words can handle. So you start to use math, which you can calculate by hand. That's good enough for gross estimates, but when you want to model time periods less than the long run, and portions of the stream narrower than the entire width of the stream, you've got to turn to computers to do the calculations.
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  38. Tom Dayton (#80) and Mileston (#82) - A note about hubris. Thankfully we aren't required to check our credentials at the door and as long as we abide by John's rules then we are allowed to stay and have fun at this party. but you never know who the other person is. I might be someone who has undergrad and grad degrees in a scientific discipline. I might have published a peer-reviewed paper in a technical journal as (Tom would say) a mere grad student. I might have 2 US Patents to my name. and although educated as an electrical engineer, i might have taken up the serious study of such topics as Astronomy, Cosmology, Quantum Mechanics and recently String Theory and Climate Science. or i could be a right wing-nut who listens to rush and fox news, couldn't think for myself and couldn't tell you the difference between an up quark and a down quark. either way, i continue to thank you all for allowing me to participate in the conversation. tobyjoice (86) - and no, i'm not taking my football and leaving. ot - was the football oblong or round? i figured we had finished up here but i'll stick around as long as you like although the frequency of my posts will diminish. it is obvious to me where our opinions differ and while you claim my opinion isn't grounded in solid science i still hold to my position. and will continue my learning journey to either prove or disprove what i now believe. as an example, it is apparent that we are having a tough time communicating (and that is because of me as much as anyone else). there is no figure 5 in Harries 2006. i assume you mean figure 3 (which is the last figure in the paper) and i updated my AT article to include that figure. And figure 1 of the first paper i cited supports my argument - actual measurements of OLR emission have increased in the area where CO2 absorbs.
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  39. @garythompson, Ok, lets keep it simple: Go to: http://ams.allenpress.com/perlserv/?request=get-document&doi=10.1175%2FJCLI4204.1 Open the pdf version. Figure 5 is on page 3990. Your comments, please? I tried to copy & paste one of the charts but only for the caption: FIG.5.The differences between the average observed spectra and their statistical signifi- cance.(a)TheAIRS–IMG(2003–1997)difference spectrum,(b)the AIRS–IRIS(2003–1970) difference spectrum,and(c)theIMG–IRIS(1997–1970)difference spectrum.
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  40. Gary, you keep arguing that AGW theory requires OLR in the CO2 bands to decrease, while you refuse to allow any detailed qualifiers in that prediction. The actual prediction is not a short, obligatory phrase of introduction from a paper. The actual predictions are the models' outputs--the outputs that were compared to observations, and found to match. Those models' outputs are of total OLR in those bands, due to all mechanisms--CO2, water vapor, and a bunch of other things. All those are included in the model, because it is the net effect that is being compared to observations. The net effect must be the focus of the comparison of model to observation, because we can't directly observe only the OLR that is escaping past only the CO2. There do exist models that deal narrowly only with CO2. Those models are incorporated as subsets of the models we've been discussing. If those CO2-focused portions of the models were incorrect, the overall model's net output would be incorrect. But the overall model's net output is correct. So the AGW theory's prediction is validated.
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  41. @tobyjoice (89) - ah, the griggs, harries paper - got it now. i covered this in post #67 (6th paragraph) but i confined my comments to figure 4 and not figure 5. i'm sorry i dropped the ball on answering your question but i hope to rectify that now - here are my thoughts on figure 5. the bottom 2 graphs are over a longer time frame and as i'm told many times by those on RC, you need decades to assess climate change (not anything less than 10 years). so the bottom two graphs on that figure (which look at deltas over 27 and 33 years) show a rise or no change in OLR emission in the spectrum associated with CO2 absorption. Of course the spike in both of these figures i alluded to in my post #84. the author offers various expalanations for this spike down and i raised the question why it shows up here and not in the other Harries paper that covers the same geographical region and the same time period. i agree with you though that there was a decrease in OLR emission from 1997 to 2003 but then again, i'm going to side with the guidance i have received from others at RC about choosing my window of time wisely. otherwise i could say that global warming has stopped since the HADCRUT3 temperatures have been stable over the past 10 years.
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  42. @garythompson, In my view, figure 5 destroys your revised statament in AT that: "Since half the wavenumbers experienced a decrease and the other half experienced an increase, the data is not compelling enough to make conclusions either way with regard to OLR for these wavenumbers associated with CO2 absorption" As Figure 5 shows,the vertical grey bans indicate regions where the differences in spectra are significantly different from zero. The legend beneath the chart says: "The regions of the difference spectrum with 95% statistical significance that the differences shown are nonzero are shaded with vertical gray lines." The number of such shaded areas is striking, particularly in Figure 5 (b). If you superposed the 3 charts (a), (b) & (c), the CO2 absorption band would be almost entirely grey, indicating uniform difference from 0 across the band. For you to prove your conjecture, you must demonstrate that these regions of statistically significance differences are of no consequence. Your handwaving explanation (above) just does not cut it. So I am sure where this came from: "...so the bottom two graphs on that figure (which look at deltas over 27 and 33 years) show a rise or no change in OLR emission in the spectrum associated with CO2 absorption" I repeat: the graphs show a statistically significant difference from 0 over substantial regions of the band. You can't argue black is white. This has nothing to do with time windows. The guys at RC prbably are top notch for climate science, but time windows are no part of the point I am trying to get across to you. The points you raised were interesting, and thank you for what we have all learned here. But your article at AT is grotesquely triumphalist in tone and should be retracted.
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  43. In para 6 of the foregoing: "So I am sure where this came from" should read "So I am not sure where this came from".
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  44. At the risk of flogging this one to death, and for my own benefit, I have been thinking about the differences in the 1972 & 1997 spectra. The Harries (2006) paper finds significant differences in the spectra between 1997 & 1972 for certain wavelengths (or rather, the subtracted spectra are significantly different from 0 over certain wavelength bands). Is this enough to show a difference in general - for some wavelengths, there seems to be no difference, right? Suppose there are equal numbers of wavelengths with and without significant differences (which is Gary Thompson's point)? What does that prove? My way to resolve this is mathematically. Suppose 1972 radiation = f(x) + noise 1997 radiation = g(x) + noise To investigate if f(x) and g(x) are equal we look at f(x)-g(x)for values of x.. if we just get noise (mean 0) at all values of x then the functions are equal f(.)=g(.) Now functions may be equal over part of their support e.g. f(x)=x and g(x)=x^2 are equal at x=1. If you just took samples from x=0.95 to x=1.05, you might be hard put to tell a significant difference. So (to repeat!) functions can be equal for parts of their support, and unequal elsewhere. It is where there are significant differences that count. Strictly speaking, you can say that these functions are equal over the inverval [x1,x2] and unequal over the interval [x2,x3]... but clearly there are not equal over [x1,x3]. Therefore, clearly the functions f(x) & g(x), representing the values in different years are not equal over the wavelength range, & Gary's point is unproven.
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  45. Gary's recent comment about wise selection of a time windows seems invalid to me. Climate change as assessed by surface temperatures is one thing, CO2 forcing another. The former is influenced by many different forcings, some cyclical (solar cycles), some intermittent (volcano aerosols), and some monotonic (CO2). Surface temperatures also are modulated by complex and variable coupling processes to oceans and ice. But enhanced greenhouse effect depends little on any of those couplings and other forcings. It results from CO2 concentration increases, and our CO2 emissions are well mixed up to the stratosphere within a year or so, I believe. So, the reason for not trusting the change in spectra from 1997 to 2003 (albeit with minor qualifications) seems ill motivated.
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  46. Well, if anyone is still here on this blog.. and makes it through to the end of the comments.. Check out American Thinker – the Difference between a Smoking Gun and a Science Paper
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  47. Thanks, Steve. That looks like an interesting post. I only had time to skim it now, but I look forward to reading more carefully later.
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  48. Yes, thanks, Steve, for that link! It explains clearly and thoroughly what I tried to explain in my comment 90 "Gary, you keep arguing that AGW theory requires OLR in the CO2 bands to decrease, while you refuse to allow any detailed qualifiers in that prediction.... [But] the actual prediction is not a short, obligatory phrase of introduction from a paper. The actual predictions are the models' outputs." Much more clearly, the author of ScienceOfDoom wrote
    For the authors of the paper to assess the spectral results against theory they needed to know the atmospheric profile of temperature and humidity, as well as changes in the well-studied trace gases like CO2 and methane. Why? Well, the only way to work out the “expected” results – or what the theory predicts – is to solve the radiative transfer equations (RTE) for that vertical profile through the atmosphere.... Now it is important to understand where the temperature profiles came from. They came from model results."
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  49. I have the utmost respect for The Science of Doom website and posted comments on his first rebuttal of my AT article which prompted his 2nd post which, while I read it, didn't feel the need to post any further comments. In that 2nd Science of Doom post (which is referenced in comment #98 above) he basically made the statement that models are the foundation of the theory. It doesn't matter that actual measurements don't validate that theory and it's only when we plug those measurements into models that we reach the conclusions that models predict. Surprise! I don't agree with that circular logic and stated that in my comments to his first post and felt no compulsion to replicate those same arguments. And I have yet to hear an answer to the question why climate models predict temperture increases three times what is observed from CO2 increases. This was stated in the Philopona 2004 paper entitled "Radiative forcing - measure at Earth's surface - corroborate the increasing greenhouse effect." If a model is off by a factor of 3, then it can't be used to validate theory. Are there other errors in the climate Models? In the papers that were referenced in the AT article the actual OLR measurements didn't decrease in the range that CO2 absorbs but only after compensating for humidity and temperatures and plugging them into models did the OLR magically decrease. CO2 continues to increase at a rate faster than temperatures are increasing so I agree with Ramanathan that if the theory is true, it won't matter what the surface temps are, OLR should decrease if CO2 is trapping the OLR. I don't see how you can have faith in models that are off by a factor of 3.
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    Moderator Response: You are incorrect. The measurements are not plugged into the models. The models are not wrong by three times. In the Search field type "models are unreliable" (without the quote marks).
  50. gary I'm not sure you have read that Philapona paper with due diligence. Yes it states that changes in DW LW were three times larger than predicted by a GCM, but that paper also ends with the sentence "The resulting uniform increase of longwave downward radiation manifests radiative forcing that is induced by increased greenhouse gas concentrations and water vapor feedback, and proves the ‘‘theory’’ of greenhouse warming with direct observations." Rather than dismissing one statement out of hand, it would be better to understand how the two statements could coexist in the same paper. Turns out the difference you note was because the GCM predictions were average northern hemisphere values forced with a 10% change in CO2 when only a 3.3% change actually occurred. The humidity and cloud levels in central europe were higher than predicted based on a 3.3% increase although in line with a 10% increase) in CO2 because of changing regional atmospheric circulation (due to NAO) across central europe, along with their attendant effects on local cloud cover and humidity. The measured changes LW radiation were actually in line with measured changes in humidity, cloud cover and GH gasses. It's just the changes in the first two parameters were both a function of GH driven climate change and regional weather patterns. Look, I'm a biologist. I have no expertise in this field - like which GCMs are better etc. Still, I can understand a fair bit of the nuance behind what they are doing. Did you even ask Philapona if his paper entitled "Radiative forcing - measured at Earth’s surface - corroborate the increasing greenhouse effect" discredits the greenhouse effect? DB is also right. Model verification in GCMs is not model fitting. They are very cognizant of that problem as you would realize if you ever read deeply in that literature. There is also nothing "magic" about models.
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