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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 94151 to 94200:

  1. Visualizing a History of CO2
    Beautiful!
  2. Climate sensitivity is low
    RW1 @185, sorry, I don't recognize the quote. Could you please cite the source and link to it if on the web. If not on the web, could you please embed the quote in a wider context.
  3. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    Moderator - sincerest thanks for allowing the discussion to continue.
    Moderator Response: [DB] While I'm skeptical that the direction of this comment stream will bear fruitful results, you have made a commitment to adhere to the Comment Policy (my many thanks on that!) and others have shown a willingness to engage you. As such, no one wishes to stifle discussion and ongoing dialogue between interested parties.
  4. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    scaddenp at 17:30 PM, for as long as I can remember, there seems to have been a constant point made by various contributors about scientists salaries being relatively modest. So much so that one could be excused for considering that perhaps it is not the desire to get rich that directs them, but perhaps understandably the desire to survive.
  5. Climate sensitivity is low
    RW1 @184, evidently you do not know all this. You may think you do, but that is another question entirely. Consider the "atmospheric window". An "atmospheric window" is any part of the spectrum where transmittance is sufficiently high that you can place a telescope on a mountain, and observe the stars effectively at that frequency. Alternatively, it is a part of the spectrum where the transmittance is sufficiently high that you can use it as a channel for communication to space. If you want to see the atmospheric window in the IR spectrum, you should look at the back radiation at the surface: Clearly, if you looked up at 680 cm^-1 wave number, all you would see is the thermal radiation of the atmosphere. You would not even be able to see the sun in that portion of the spectrum, from the surface. In contrast, the intervals between 810 and 950 probably have sufficiently high transmittance to be useful for telescopes (and sidewinders). That is a atmospheric window. There is another, smaller one on the other side of the O3 trough. With that in mind, closing the window means reducing the IR radiation from the surface that escapes to space, particularly in those parts of the spectrum; and it is a minor effect. Deepening of the CO2 emission band means that in that part of the spectrum outside of the atmospheric window, the amount of IR from the atmosphere itself is reduced because it comes from a higher altitude and hence has a colder temperature. These effects are not strictly independent. For example, at the right edge of the CO2 trough, there are transmittances that rise from around 0.2 to 0.8 over a 60 wave number interval. Over this interval, both trough deepening,and narrowing of the atmospheric window occur with rising CO2. On the equivalent left side, however, transmittances peak around 0.2 because of the overlapping effects of H2O. The trough deepening, however, contributes almost as much to the reduced OLR as does the equivalent on the other side. Speaking of which, on the graph shown, total area under the line equals the total power (watt's per square meter) radiated to space, so the difference in area is the difference in radiated power. As you can see, the most significant part of this comes from the deepening of the trough on the wings, and that is approximately equal on both sides, even where transmittances are very low. Therefore it is clearly not a narrowing of the atmospheric window.
  6. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    scaddenp – please forgive me as I only have the energy to address one statement of yours right now, (Moderator – I’m directly answering a question). Personally, I think Al Gore started out as a true believer in the horrors of anthropogenic CO2. Now, I think he is just invested. I realize I’m being cynical, and if I’m wrong, my sincerest apologizes to Mr. Gore (no sarcasm). So, I don’t believe he would ever have invested in oil and your question is therefore too hypothetical to answer. I have a reason for believing that Gore is “invested”, it is indirect and admittedly spins off of Green Peace. More on that another day.
  7. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    Tom - I appreciate your thoughtful counter-point and respectfully disagree. Including Oil revenues without considering their expenses and capital investment expenditures is completely missing the mark. Big Oil must actually spend money to make money. When the gov't gives away Billions of dollars and props up the "green" industry (as was done in Spain, et al) with tax payer dollars - we are not comparing apples to apples. Also, the intention of including #5 was not for the purpose of total global dollars spent, but to point out that $100 Billion a year wasn’t enough and that the motivation is a money grab. (you can claim that is conjecture - again, I will disagree). However, I will concede your point that the fund is not locked in yet - that fund is a great example of true politicking. Regardless, the point of including that fund in the list is to point to the dollar motivation of the “green” team. Unfortunately, the formula isn’t as simple as donations. Daniel’s original statement was, "Fossil fuel interests spend hundreds of millions of dollars in the US every year to lobby against any controls on fossil fuels and CO2 emissions. Vast riche$ await anyone who can scientifically break the chain of evidence & show the AGW is a non-worry (I'd chip in a couple of hundred myself)." The first sentence is accurate; the second sentence is where I’m taking issue. With Billions of dollars being GIVEN to green technologies, this constant whining about oil lobby dollars rings hollow. With regard to your last paragraph - I disagree (I know, you’re shocked). As the hour is late, any further support of my position will have to wait for another day.
  8. Preference for Mild Curry
    Tom @17 What she said was that at a 90% level, the bounds are 0-10 degrees. This implies that 10% of the time the sensitivity would be outside that range. If she doesn't accept that sensitivities can be less than zero, then that would mean that there's a 10% chance of it being over 10 degrees. But you should read the the thread I linked to for yourself. I would guess that what she meant was that she doesn't know (or won't say) what the sensitivity range is, so she threw up a big range and said that was the 90% certainty range for good measure. Of course, recognizing more uncertainty does not mean less action is required, on the contrary, more uncertainty means that exceptional outcomes are relatively more likely than in a more tightly bounded probability distribution. It's a pity that we have to guess what she means.
  9. Preference for Mild Curry
    HR @19, actually, I expect them after considerable expense to end up confirming current estimates. I then expect the entire project to be dropped quietly before publication, because I don't trust the principal's bona fides. Of course, they may show some integrity and publish. Of course, given that they have no-one in the team experienced in temperature reconstructions, they may accidentally or deliberately not adjust for surface station distribution, or treat long records from nearby stations as blendable without adjustment as denialists are wont to do. As the team leader has already been caught out in data manipulation (while trying to slander Jones, Mann and Briffa on a charge of data manipulation), I would be foolish to assume this will be an honest, and competent endeavour until they prove otherwise.
  10. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    NQA - the not-so-simple fact is the scientists on the "AGW side" are not trying to make money. If you actually want to make money, it far easily to money from other side where any sort of shonky argument will do. And you can get really rich, which you cant on science salary. IEA estimates fossil fuel subsidies in 2008 at $557B annually. That represents a lot of shareholder value to protect. If you ended those, you would pay more for energy but less for tax. Seem like a good idea? Not if you live on coal subsidies. NOAA spends its money on instrumentation largely. Now if Al Gore invested in oil, what you say? I will agree that if you want to make money by investing in new technology, then investing in green technology is the way to go. That's what we need - who wants to freeze in the dark on the back of a horse? But the DB argument that you object to wasnt about technology - it was about investment in climate science -finding out what its all about - versus investing in lobbying and dirty tricks. That's the difference.
  11. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    NquestofApollo @122, your list is interesting, but it is not an apples and apples comparison. You are comparing Oil Industry money spent on lobbying alone with with the total revenue for research (most of which does not end up in scientists pockets), industrial applications, and profits from "green activities". For an apples and apples comparison, you would need to compare that list with the total oil company revenues, which was over a trillion dollars in 2009 for the top four companies alone. Even that is not a fair comparison, because that is a single years actual revenues, while your big ticket items are multi year expenditures, and in the case of 4 & 5, double counted and not even locked in yet. Another apples and apples comparisons is total donations to political parties in the US. Oil and Gas companies donated over 45 million dollars in 2102. Less than 3 million was donated by the alternative energy industry. Just shy of $19 million was donated on environmental issues, but that is as likely to include Koch brother donations as it is Al Gore's. Any way you slice it, there is more money to be made in, and by appeasing the oil industry (not to mention the coal industry) than there is in environmentalism. And much more to be made in spruiking denialism then there is to be made from doing climate science.
  12. Climate sensitivity is low
    Tom, "The decrease in transmittance directly tells us how much more outgoing surface power, across the entire emitted spectrum, is absorbed by the atmosphere." If 'transmittance' does NOT tell us this, then what does it tell us?
  13. Hockey Stick Own Goal
    HR - in my reading of the paper, they estimate global forcings, run a GLOBAL model, and then extract from that model the temperature series for NH. They are not trying a simple-minded application of sensitivity no.s Remember that sensitivity is an OUTPUT of a model, not an input.
  14. Climate sensitivity is low
    Tom, "As regards the window, the figure above @ 171 shows the radiance for 325 ppm CO2 overlaid on the radiance for 750 ppm CO2 on the right. As you can see, the main difference is on the wings of the trough, where a slight step pattern is deeper with 750 ppm than with 325 ppm. That is not a change in the atmospheric window, because IR radiation at those frequencies were already absorbed, possibly completely absorbed as far as radiation from the surface is concerned. If you look even closer, (closer than the resolution will allow, unfortunately), you will also see that the center of the trough is slightly deeper. You will also see the walls of the trough at the top are slightly wider (which is a reduction of the window). You will also see some of the secondary troughs generated by CO2 are deeper. There is one just to the right of the main CO2 trough where a single spike shows up in the center." I know all of this. The total atmospheric window is simply the quantity of the whole spectrum of surface emitted infrared that passes through the atmosphere completely unabsorbed and goes straight out to space. Visually, there is a slight widening of the CO2 absorbing bands at 750ppm, which narrows the more overtly visual part of the 'window', but it's a specific quantity - not just a visual reduction. The outputs of these programs are detailed numbers, specifically the transmittance - not just what can be seen overtly in visuals of a graph. The decrease in transmittance directly tells us how much more outgoing surface power, across the entire emitted spectrum, is absorbed by the atmosphere.
  15. Preference for Mild Curry
    16 Tom Curtis So if they find that all the other temp records are essentially the same as their result then we should scrap the lot? Not even prepared to give this a chance?
  16. Climate sensitivity is low
    RW1, I cannot keep up with your stream of consciousness posting, and nor will I try to. Sit down, think it out, and work our your objections and problems after a little thought. As regards the "average transmittance", I have seen a comparison of the Modtran model at David Acher's site with the data from a satellite over Barrow Island, and the match is pretty good. Close enogh that you can't tell the difference by eyeball, although if you overlaid them I'm sure some differences would jump out. The "error" you have found is too large for that to be plausible. If you have a further problem with it, work the problem out line by line as I suggest. If you are correct, there will be no difference in the reult. If I am correct, you initial calculation will be shown to be in error. As regards the window, the figure above @ 171 shows the radiance for 325 ppm CO2 overlaid on the radiance for 750 ppm CO2 on the right. As you can see, the main difference is on the wings of the trough, where a slight step pattern is deeper with 750 ppm than with 325 ppm. That is not a change in the atmospheric window, because IR radiation at those frequencies were already absorbed, possibly completely absorbed as far as radiation from the surface is concerned. If you look even closer, (closer than the resolution will allow, unfortunately), you will also see that the center of the trough is slightly deeper. You will also see the walls of the trough at the top are slightly wider (which is a reduction of the window). You will also see some of the secondary troughs generated by CO2 are deeper. There is one just to the right of the main CO2 trough where a single spike shows up in the center. Here for comparison is a modtran graph for 10,000 ppm CO2 with not H2O or O3: You will notice that that small spike noted above has become a deep trough that overlaps with the first trough, with a resulting large reduction in the atmospheric window. But that widening took place step by step, and in each step, it was always the smallest effect.
  17. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    scaddenp – I appreciate everything you have to say, but, at the risk of continually being annoying, I was specifically addressing the one-sidedness of Daniel’s comment on the millions big oil is spending while ignoring the money being made on the AGW side. I’ll try to post my counter points again (again risking being deleted): 1. NOAA alone has a "climate change" budget of $437 million. 2. President Obama Awards $2.3 Billion for New Clean-Tech Manufacturing Jobs. 3. Al Gore is in line to become a Billionaire from investments in green technologies 4. Secretary of State Hillary Clinton said the US is willing to contribute to a $100 Billion a year fund to help poorer countries mitigate the effect of climate change 5. Developing nations want $200 Billion 6. Spain's PV solar plants, which directly convert sunlight into electricity, have been charging nearly 10 times the wholesale price. Big Oil companies would have to spend 46 times more just to match POTUS's awards alone. Al Gore stands to be (single handedly) worth double what they've spent. (this is not an attack on Al Gore – congrats to him, I’m strictly putting the numbers in perspective.) And we haven't even discussed what the rest of the world is spending. The very simple fact is that there is more money to be made on the AGW side than the opposition. So, when one claims that there are riches to be made against AGW, I can’t shake the feeling that I’ve entered the Twilight Zone – and THAT has been my only argument here. Why is that so difficult to understand?
  18. Climate sensitivity is low
    Tom, Is it just a coincidence that using the average transmittance numbers and dividing the surface difference by 2 yielded nearly exactly 240 W/m^2 leaving (for 255K)? Maybe, but it certainly warrants further investigation.
  19. Climate sensitivity is low
    Tom, Nor do I see the 252.801 W/m^2 or 255.565 W/m^2.
  20. Climate sensitivity is low
    Tom, "Which is more likely, that a program developed by the air force for research and which has been used in various incarnations since 1988 with good correspondence to observational results has an error that produces up to 20% errors in its output? Or that you are simply mistaken in your interpretation of average?" Not the program itself, but the web interface integration of the program. Where do you see the 2.764 W/m^2 in the line by line output, either directly or indirectly? I don't see it in there.
  21. Climate sensitivity is low
    Tom, What use would the 'average transmittance' number be if it were NOT how I interpreted it? Maybe you're correct, but then the information is totally useless as far as I can tell.
  22. Climate sensitivity is low
    I can't find the manual online. I emailed Ontar to see if they can provide it.
  23. Climate sensitivity is low
    "Why is it that you cannot accept that it's two effects adding up to the total IR reduction?" Simple. I haven't seen the evidence showing/prooving it, nor do I understand what a "deepening in the GHG emission bands" actually means.
  24. Climate sensitivity is low
    RW1 - Why is it that you cannot accept that it's two effects adding up to the total IR reduction?
  25. Climate sensitivity is low
    RW1 - "Do we agree that the reduction in the window should be twice the 2.764 w/m^ outputed" Ummm, absolutely not. It's both a reduction in the atmospheric window and a deepening in the GHG emission bands. As we have said repeatedly. Not just a single effect, but two different ones that make up the total reduction in emissions.
  26. Hockey Stick Own Goal
    119 scaddenp "One other thing though - you shouldnt be just looking at NH temperatures with a global forcing. " I won't argue with you. All the reconstructions are essentially NH even those that purport to be global. Hegerl's work was based on NH reconstructions. So it's not just my problem it's the whole scientific field. I suggest you write to teh IPCC with your concerns.
  27. Climate sensitivity is low
    Tom, Do we agree that the reduction in the window should be twice the 2.764 w/m^ outputed (or about 5.528 W/m^2)? If not, why not? You don't think that all the infrared the atmosphere absorbs is directed toward the surface? Clearly it's not.
  28. Hockey Stick Own Goal
    115 Tom Curtis Tom when you write MWP do you mean MM (Maunder Minimum)? The volcanic forcings in fig5a don't go back as far as the MWP. I've pasted the volcanic forcings from Hegerl 2006 Fig2 (1000AD to 2000AD) into the corner of Dana'a Fig 1. The idea isn't to show the absolute magnitudes but to show how the periods of peak volcanic activity match to the temperature record. The problem I have with the importance of volcanic forcing is that it's very short lived. I see the MM coincides with a period of high volcanic activity but it doesn't really explain how we got to the MM. What I mean is the MWP to MM period is 600-700 years of declining temperatures. This period has periods of both high and low volcanic activity. I'm not sure of the resolution in the temperature reconstructions but volcanic may explain some large negative departure in some of the data points (maybe for example those very low spikes at the MM) but they can't really account for the multi-centennial trends. In regard to your mathes wouldn't you have to take some sort of mean volcanic forcing over the full MWP-MM period? The only real forcing likely to explain those longer trends are solar except as I keep saying it appears that TSI changes are far too small to explain them. "First, there is nothing wrong with allowing the change in forcings but keeping Hegerl's reconstruction." I think we both agree that both fields (paleotemperature reconstruction and TSI reconstructions) are fields of science that are in flux, if not still in their infancy then going through a painful adolesence. My contention is the newer paleotemp estimates should be matched with the newer TSI estimates but I concede there is no absolute logic to that. But retain all the estimates and you end up with a spread of climate sensitivity that is so wide to be almost meaningless. As you say the IPCC may not exclude climate sensitvity being between 5-9 but just based on the image in #109 then other parts of the science are going to struggle. It looks like models won't handle those well or the LGM. That was my earlier point I think this is not just a problem for skeptics.
  29. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    BTW, Daniel, remember that - in my many deleted posts - I agreed with the factualness of your snarky comment. Is it really impossible for us to agree that, even within sarcasm, the comment was one sided and designed to bolster your world view?
  30. Climate sensitivity is low
    wrong version.
  31. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    NQA - but he is right. Any half-convincing line of evidence against AGW would be funded instantly and if you overturned science, you would have a Nobel prize. That's an incentive but you cant make anything fly. Sad. The money poured into climate research goes mostly into satellites. Scientists are not well paid. Not so for coal executives. And as for me, well I am oil and coal man! And end to those would definitely affect my funding streams. I dont think there is a single person in my department who doubts the reality of AGW either. However, I cant actually imagine that there is no use for my skills, no other problems to solve so I don't exactly fear unemployment. What I do think though is that you seek the truth however personally annoying it might be. What I do find repellant is suggestions that AGW theorists are scheming, pushing some political agenda, looking at the data one sided etc. There is a dearth of any other sensible way to look at the data. Only deception practised on blog sites and other media.
  32. actually thoughtful at 15:12 PM on 28 February 2011
    Preference for Mild Curry
    What I find most confusing is that people are going back in time to make these accusations. When these reports came out, no one was attempting anything nefarious, the results weren't THAT controversial, a few liberties in the artwork (explained in the text) not only weren't out of line, but they were helpful in communicating the main message that we were in trouble. Have any of you skeptics ever given a presentation to your peers, and also to the general public? How does that differ from the work you do by yourself? I find I ALWAYS have to simplify, even for my peers, unless we have a weekend workshop or an entire semester to dive into the minutia. And my subject matter is plumbing! If anyone had dreamed of the level of scrutiny - of course they would have been at pains to point out that one of the 13 squiggly lines was truncated (or left it in there). This is, in essence, a rewrite of history to paint these professionals as bad guys. The only trouble is there are millions/billions of us who were alive when the history happened, and we simply are not letting the revisionists get away with it.
  33. Climate sensitivity is low
    I'm downloading the manual.
  34. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    Daniel, my apologies that my first post (which was promptly deleted) seeemed to attack the messenger. I did my best to clean that up in later posts. Which were still deleted under the guise of being ideological motivated. They were not. They specifically countered a statement you made. When you are ready to address the reason you made such a one-sided statement, I will happily engage in a conversation with you and promise to do my utmost to refrain from anything that seems like an attack.
  35. Climate sensitivity is low
    KR @167, that is the model. If you run it there will be a link to "View the whole output file" which shows a large number of additional values. RW1 @168, as can be seen in this image, the peak of the surface transmission is in the 400 to 800 wavenumber band, ie, in the band with a deep trough due to CO2 and a number of troughs due to H2O. The peak radiance is at wavenumber 592, inside the left hand side of the CO2 trough. Therefore if the average transmittance is the mean, it would definitely underestimate the reduction in outgoing IR from the surface. @164 and 165, I don't know, but that seems the most natural reading to me. You should always take average to mean "mean", not "weighted mean" (or median or mode) unless there are clear contextual reasons to think otherwise. There are no such contextual reasons here; and furthermore, your discreprancy gives weight to that interpretation. Which is more likely, that a program developed by the air force for research and which has been used in various incarnations since 1988 with good correspondence to observational results has an error that produces up to 20% errors in its output? Or that you are simply mistaken in your interpretation of average? Regardless, if you disagree with me, you do the LBL integration. I am not the one chasing windmills here. @169, no, you just add up the individual lines. Any divisions (if necessary, see 163) shoud be done for each line only.
    Moderator Response: Fixed image width.
  36. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    scaddenp – it remains stunning to me that my point is constantly missed. It is so very simple: when one sees only one side of an issue, it is evidence of a clouded view. Daniel, in his post, could only see the millions big oil has spent while ignoring the billions that team AGW is making. His comment was exactly this: “Vast riche$ await anyone who can scientifically break the chain of evidence & show the AGW is a non-worry”. The current state of spending is so completely OPPOSITE of this statement as to cause me to wonder about his motivation. For Daniel to make such a statement and then have the moderators (of which he is one) accuse me of engaging in politics is Orwellian. My point is NOT to bring politics into this issue, but to address his insertion of politics. And I have to apologize to you, I’m not good at substituting words and your critical question isn’t quite phrased correctly, so I can’t answer you. If you can rephrase this, I’ll give it an honest shot: “Got some EVIDENCE that scientists are doing the world a favour by pointing out that their is a problem are somehow making huge amounts of cash?”
  37. Climate sensitivity is low
    RE: my 168 Actually most of the energy is not really in the window.
  38. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    Re: NQA (113, 114) The focus of my comment @ 109 (itself a response to your question @ 108) was points 1-8 of a logical evidenciary chain. That you focus instead on an off-the-cuff (albeit snarky, but entirely factual) throwaway quip instead of an objective dialogue-based examination of the underlying science is both telling and troubling. Resorting to the "attack the messenger" ploy may be considered both acceptable and de rigueur in other venues...but not this one. If you wish to discuss the underlying science of both climate science and anthropogenic global warming and avoid the personal attacks - then Skeptical Science is an incredible resource for learning and the sharing of knowledge in a setting protected from the emotion colouring most other sites on the internet. Here, lay persons rub elbows with scientists of all disciplines. Here, one can learn apace at leisure alone or pick the brains of experts directly. If you wish other forms of dialogue and interaction, then Skeptical Science is not the place for you. Your call. Back to the Oscars, The Yooper
  39. Preference for Mild Curry
    Andy S, so Judith Curry is publicly on record as asserting that there is a 5% chance that changes in forcing have effectively zero effect on global temperatures? Anyone who can think that there is at least a 5% chance that the changes between glacials and interglacials is entirely brought about by internal cyclical changes in the environment (as this entails) is massively disconnected from reality.
  40. Climate sensitivity is low
    Tom, Should I add up all individual transmittance lines and divide?
  41. Climate sensitivity is low
    Tom, Most of the radiance is in the window, so if anything that would seem like it would make the number much higher than only about 0.25?
  42. Preference for Mild Curry
    Stephen Leahy @15, a team headed by Richard Müller (see 13 above) and with Judith Curry as the only climatologist, in a research project partially funded by the Koch brothers? I can hardly wait.
  43. Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
    NQA - everyone is allowed their values and their political opinions but there is only version of reality. It seems your arguments are largely politically inspired instead of an assessment of real science which is what DB gave you. Got some EVIDENCE that scientists are doing the world a favour by pointing out that their is a problem are somehow making huge amounts of cash? Does evidence for the Ptolemic system means there is good reason to doubt the earth goes around the sun? Do you make up all your judgements on reality on the basis of supposed motives? I think there are good reasons to be suspicious of meddling of those with a lot to lose but frankly its best to concentrate on the science, what is the best model for reality and leave the political hangups behind.
  44. Climate sensitivity is low
    Tom Curtis, RW1 - do you have a link to the Modtran model you are using? I'm not seeing the same freedom of parameters you seem to have discussed at the model here.
  45. Climate sensitivity is low
    Tom, "I know the average is given at the bottom. That does not mean you can use it as you are doing." How do you know? Have you added all the lines up and divided?
  46. Climate sensitivity is low
    Tom, 'INTEGRATED ABSORPTION FROM 100 TO 1500 CM-1 = 1054.84 CM-1 AVERAGE TRANSMITTANCE =0.2465' You're saying this doesn't account for the differences in energy emitted at each line? How do you know this?
  47. Climate sensitivity is low
    @162, I know the average is given at the bottom. That does not mean you can use it as you are doing.
  48. Climate sensitivity is low
    Addendum to 161: Looking at the values, it appears quite probable that "Surface transmittance" is the surface radiation that escapes to space at each line, with transmittance rounded to five significant figures, thus showing 0 in this case. In that case, to get the transmittance you would have to calculate independently the surface radiance at the surface for each line. However, it would save you a step in integrating determining the total emissions from the atmosphere. You may need to find a manual to clarify this. Of course, the sensible thing to do would probably be to assume that no fundamental errors slipped into the programing based on the fact that a large number of independently programed models yield essentially the same result.
  49. Climate sensitivity is low
    Tom, The average transmittance for '100 TO 1500 CM-1' is given at the bottom. Also, I tried using an emissivity of .98 and it didn't make much difference (2.3058 W/m^2 instead of 2.348 W/m^2).
  50. Climate sensitivity is low
    RW1 @158: 1) You did not account for the emissivity of 0.98 for the Earth's surface. That means Surface Radiation (SR) = 385.8 * 0.98 = approx 378 w/m^2 2) The average transmittance, ie, the sum of each line's transmittance divided by the number of lines, cannot be used as you have done it. The energy emitted at each line is not constant, so the distribution in variation in transmittance relative to the distribution in emitted energy can make very large differences in the net transmission. Therefore using a simple average of transmission will give invalid results. 3) Total radiance obviously includes values for emissions by the atmosphere, as for example at line 400: Surface Transmission: 3.18E-29 Total Radiance: 1.42E-03 Transmittance: 0.00000 Clearly with a transmittance of 0, Total Radiance would be 0 if radiation emitted from the atmosphere was excluded. To conduct the analysis you wish to make, you need to go through line by line, and sum the total of surface radiation * transmittance to get the amount of radiation from the surface that escapes to space unabsorbed. You then need to go through line by line and sum (total radiance - (surface radiation * transmittance)) to get the amount of radiation emitted from the atmosphere to space. You will then be in a position to do what you are trying to do in 158. Have fun.

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