At link to transmission/extinction coefficients for some IR wavelengths can be found here.

As indicated in the above link, the coefficients for absorption of IR in the main CO2 band beyond the atmospheric window are approximately 1. If this is accurate this means:

(a) The presence of CO2 in its main band dominates over the presence of water vapour to the extent that effects on H2O in this main band for CO2 are indiscernible at given altitudes.

(b) Assuming this is a reputable source, it indicates that while H2O may still be present, variations in the quantity of H2O within troposphere [geographically] imply (if not already), along with perturbations in absorption with altitude (Clough, 1995) that sustained and significant absorption by H2O in the main and major CO2 absorption band (between [roughly] 14 and 16 microns) is not consistent with the said absorption/transmission coefficients.


No, I was referring to the molecules, not the bands. The main CO2 band is not 5 to 7 microns, and the main H2O is not 14.7 to 16.5 microns (H2O in fact has a continuum extending from roughly 8 to 50 microns, as indicated in the essay). That is abundantly clear.

In the quote I used the word “predominantly” for the reason – science is not absolute (ideological), it acknowledges the contribution from other GHGs.

Some bands overlap, yes, but I do not see how the assumption of “deliberately vague” is supported by the content of this document. What is not there is the fact the absorption coefficient for CO2 is approximately 1, as indicated in the previously link provided.

While absorption does not add linearly (as indicated in the document), it is clear that with any coefficient of 1, one cannot expect much contribution from other GHGs in the same band (given the nature of opacity, that is: a reduction in the distance over which heat is absorbed through the atmosphere). It is also clear that, given the table listing GHG absorption bands in distinct, finite ranges, and the fact that:



Reference: http://www.eia.gov/cneaf/alternate/page/environment/appd_d.html

That it is not implausible, that a more thorough analysis and interpretation of the infrared absorption characteristics of GHGs would yield yet more distinct, finite ranges, inclusive of as yet indistinguishable absorption bands (due to the high level of complexity involved).

Additionally, the document indicates radiation of a single, finite wavelength (monochromaticity) can be lost due to changing atmospheric conditions; considering there are thousands of these, this implies integrating spectral bands over greater, discernible ranges is far more likely to give a better picture of absorption bands, despite the uncertainties involved (which the document appears to acknowledge).

Regarding the reference for the overlap presented: i.e. http://imk-ifu.fzk.de/305.php, and comparing it, at a glance, to the reference for which the listing of definitive, finite GHGs absorption bands was given:

Sources:

Snell-Ettre, Encyclopedia of Industrial Chemical Analysis, Vol. 8, p. 252;

And

N.V. Sidgewick, The Chemical Elements and Their Compounds, Vol. 11 (Oxford, United Kingdom: Clarendon Press, 1950), pp. 859-863.

Which one do you think I would be more inclined to give credence given this is meant to be a scientific discussion?

Regarding this late posting with respect to your last post…what does it matter if we’re talking about science?

it is a text version of -



at one segment of the atmosphere. so what does it mean?



it does not mean that at all, and i have shown why.



it does not indicate what you believe it does, and i have shown why so many times, it is wearing thin.



what you were talking about was individual lines ie the molecule, not bands which are a bunch of individual lines. a 'band' can be any set of lines, normally a bunched up group of lines is considered a band. this is where the document shows ambiguity. a band can be any set of frequencies, and because the absorption from water vapour is not 100% for a large part of co2s main band, they say there is no overlap. clearly there is. i posted data showing it, you posted data showing it. the many lines that water vapour has within the co2 band, the author decides that they should not be mentioned as a band, in fact they decide it should not be mentioned AT ALL!



the finite lines you see are samples of the waves spectrum. the resolution of the equipment defines how much of the line you see, but those resolutions are high enough to see the individual peaks or the main part of them. the finite bands are chosen, by whomever decided to, to represent these sets of lines finitely!, you can chose any set you like and call them xxx band. eg c-band satellite includes frequencies from 3.7GHz to 4.2GHZ down and 5.9GHz to 6.4GHz up BUT s-band radar ranges between 2GHz and 4GHz, hmm and then you have wireless products running at 2.4GHz etc all in the microwave range. there is a pile of the spectrum used and of course crossing over to other applications that sometimes interfere with each other, but that does not stop someone nominating a band S or C, its just a name for a set of frequencies.

back to the time thing. for absorption, if you want to break down each individual line in a spectrum, you MUST include the influence of EVERY other line in the spectrum at that specific point in time, which means when you consider the absorption, you are considering the whole spectrum. the absorption spectrum in the pic above shows EXACTLY the amount of energy absorbed by each molecule at that specific frequency. from the absorption spectrum we know exactly how much energy will be absorbed should that photon come in contact with that molecule. the CHANCE of contact is much higher for water vapour due to the QUANTITY of water vapour molecules, but the ABSORPTION of energy is higher for co2 in those specific bands. so while there is more water vapour there is less AVAILABLE energy for the co2 molecules to absorb.



what?



in terms of absorption, you cant separate lines from a spectrum and hope to calculate anything useful unless you consider each step in time. this assumes that the atmospheric condition cannot change over that time. using a band of frequencies to calculate instead of each individual frequency is just a short cut to reduce processing time in some idiotic attempt to model the absorption of the entire atmosphere or something similar. considering the atmosphere does not have 'average' conditions and most certainly does not live in the clear sky state, it seems a very non scientific approach to attempt to model it, or at least conclude anything from such a model.



the link there is to show the water vapour in very dry regions and the variation of days. funny how people seem to believe they are able to model such things.. anyway, you missed the rest.

i dont know what you want to highlight from the paywalled texts, so if you want to use them for something, then quote from them here.



oh authority, i see. why do you want us to ignore understanding?

I don’t want an ignorance of understanding…what I would prefer is a recognition of evidence and supporting facts over opinion and hearsay. And more importantly, an understanding of the difference between the two on scientific grounds. That is apparently not happening. Reference to papers from journals which have not just been through the peer-review process, but beyond that.

I would be happy to discuss the contents of various papers .

so, you are implying that my posts are opinion based on hearsay and yours are facts based on peer reviewed references.

here is a simple and important fact for you-

the papers you have referenced do not support your understanding.

This all started from me deciding to post an essay in which I made it clear it was my own take on some climate science (my opinion)...where I added some certainty to some uncertainty. I'm now wondering why I bothered given this appears to have turned argumentative.

And if so desired, people can check what I wrote just before I posted the essay.

No, I wasn't. We see things from different points of view and that's fine . I may have to agree to disagree in some situations.

While I vaguely understand what you’re talking about here, I’m not an expert in it…nor do I claim to be. I would suggest this is more technical discussion of physical research and/or experimental techniques (correct me if I’m wrong) rather than a post-experimental discussion and analysis. If you have a paper which has this in more detail, I might read it, but the chances are that because this not specifically about climate science and related concepts in terms of analysing data, I would be more inclined to leave it.

I really do recommend reading many [relevant] publications from the scientific literature. I would also recommend talking to people who have spent most of their careers in their specific fields (including in person), if you’re really interested and not just using online sources of information. It often also helps to get a second, third or fourth view on scientific matters, and to double-check what is presented online with what other scientists say (not just with what we think or believe is true).

spectrum analysis is nothing new. it is used in many fields, and while quantum mechanics may not be a complete field, it is not that important to understand every detail for what we have been looking at here. in short this is just applied physics. no need to define the field, though when it comes to reading a paper on signal noise or something similar you get clear, logic steps to show understanding and clear results which may or may not show what was expected. however, when reading ANYTHING related to climate science, even at the physics level, there is a clear note of ambiguity when developing the steps of understanding. the results are clear, but the methods are not, and this is the greatest failure. it is worse than quoting bogus results! eg using models as proof and a single tree proxy etc.

there are some very fundamental flaws in the way climate science is being conducted, and those that do do the right thing and follow the correct method are not standing up and preventing this affair from continuing. in the end the whole 'climate science' fraternity will end up looking much like astrologists, so i have no plans in developing my understanding how the planets alignments may influence virgo during december..

you advise me, so now i advise you, if you are entering or are in the 'climate science' field, then make some escape avenues.

Thanks for clarifying . I would like to say though that there is a lot of material out there (literature or similar) which has the potential to explain things about the climate without reference to AGW.

“Nature of observed temperature changes across the United States during the 20th century,” Climate Research, Vol. 17: 45–53, 2001.

I was specifically talking about “the main [thermal] band in which carbon dioxide absorbs” and “the main [thermal] band in which water vapour absorbs.” Find those main bands and that is the answer you’re looking for. Any other bands/overlaps that do not corresponding to the main [thermal] bands for specific GHGs are beside the point.


Where is your evidence of it being deliberately vague?


Scepticism is natural in science, not prejudicial or skewed towards a particular stance.

I really don’t care about the politics of this whole debate; it’s better left in the appropriate thread. If we want to talk about scientific papers and analyse what they say without making comments on their credibility but rather on their scientific know-how and content, that’s fine…

in fact the last however many pages are due to this documents lack of clarity.

It's one of many documents/reports that could potentially be interpreted as lacking clarity...and that doesn't mean the interpretation is inaccurate, it just gives an idea of the extent of issues with concise and accurate reporting of facts. If we were to look for fixed facts, figures, statistics, graphs or the like, we'd probably encounter the same issues.

sorry, but i dont see it that way. i believe their interpretation is correct and that the deliberate omission of CRITICAL information which relates directly to the subject matter is not designed to improve the readers understanding, it is a design to confound, confuse and mislead. there are also points added which are added purely for impact. impact should not be needed in a scientific document.

working mainly with reference text in my past, perhaps i see it from the point of view that these things are unexpected in such a document, so i do see fault in it, but i believe this is the correct way to view it. ALL pertinent information should be presented clearly to help the reader understand. to claim that this document is not being misleading is to claim that the information mentioned before is not pertinent.

I didn’t read it [Appendix D, which is only part of the whole publication] that way and I tend not to make assumptions about the intentions of the authors beyond the context of the information presented unless there is something glaringly obvious. I might be wrong but I’m not going to fuss over it! Like you said, pages about one document…!

As far as I could tell it was pretty clear and understandable, and the way I would go about checking it would be to look for journals with similar publications [including in the reference list]. There might be some room for improvement, because as it stated there are some uncertainties involved, but if we’re going to be pedantic about it we might as well do a comprehensive literature review, inclusive of all the references it lists [for the entire publication]. I don’t intend to be pedantic about it because there is the likelihood of being bogged down in details where I only have a moderate understanding of what’s going on and am no expert [plus I miss the bigger picture].

what assumptions??

this is the page-


it clearly misleads. context is clear as can be.



yet you clearly misunderstood it the way they 'clearly' wanted you to.



and even after pointing out this fact several times, you continued down the path you were already on in the disbelief that they would mislead you in such a way.



leaving out critical information is not about uncertainties.



we are talking about the crux of developing an understanding of the earths climate system. this is just the start, the most basic physics and also where the most certainty resides. everything after this is less certain, and the documents become MORE vague, and mostly deliberately eg as with the pierrehumbert (realclimate co-founder) document pg raised.

Exactly!

Some things I don’t post...maybe because of the expectation that someone will jump down my throat for stating things as I read them, like this:

About the Frequency and Number of Global Tropical Cyclones

Reading through reference ar4-wg1-chapter9, on page 711

In 9.5.3.6 Tropical Cyclones, it clearly indicates there appears to be little evidence of a trend in the observed total frequency of global tropical cyclones up until around the late 1990s (giving publications for reference).

It then indicates there is some evidence of the number and proportion of the most intense global tropical cyclones increasing over the most recent 35-year period.

Whether that means the most intense global tropical cyclones are going to become more common is open to question.

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At the risk of getting reactive comments to this...I would like to contradict claim that this “AGW driven”...I’m not interested in “global warming” or “global cooling” as such (it might come up because someone mentions it, but I prefer to keep clear of it).

It seems there is a lot of stigma attached to the concept of “AGW,” for better or worse, due political references being made in relation to it, which can have the potential to distort perceptions of what’s going on in science. It is concerning that political opinions and excerpt of information from political or non-scientific sources can be taken with more weight (in the public eye) than the same things coming directly from scientific sources. The language used in politics and science is different. Very different in fact, I believe. Perhaps some find this a “turn-off” because they don’t have the time/patience/skill/background to be reading through an entire technical scientific publication, or have more pressing concerns, which is fair enough. Unfortunately, when this is true and we think we have been given the “wrong” information or facts, in our own eye, a criticism of science (or rather the scientific information disseminated in the community per both a mix of opinions and actual scientific facts) can follow, because we cannot “decipher” this information. Part of this may be due to the “entertainment” side of modern science, the other, well, perhaps because we don’t hear what we want to (evidence rather than an opinion), or it may actually be a legitimate complaint (this would imply whoever reads the information knows what they’re dealing with), who knows. And therein lays the issue – what is an opinion and what constitutes actual, legitimate evidence with a theoretical interpretation we can have some confidence in.

An opinion is a point of view (like this) where evidence and facts (via scientific references) are not provided. I have often erred on the side caution when reading through some of the comments in this climate section because of this – a lack of references. These are the sort of non-political references where we actually have to do some searching ourselves, not just quotes from any sources we prefer. Original sources, in my eye, tend to be the most reliable and reputable, assuming no mistakes are made. It’s sometimes difficult to do this, but as a rough guide, if we are interested enough, it can be relatively straightforward.

All that said science is based on evidence and theoretical interpretations of that evidence according to what we can or do understand. Politics is much more publicly aligned and aimed the concerns of the voting majority, and is more or less guided by opinions and public debate (as opposed to evidence and scientific debate).

I do not have the intention of maintaining this thread. However, I am interested in understanding things about how the climate works (biologically, physically, chemically, geologically, meteorologically, hydrologically, palaeoclimatolgically, etc.). I don’t think this is about whether information is “right” or “wrong” in my eye, so much as in the eye of published material. To that extent I have not been posting in here to convince anyone of anything, nor will I simply take anyone else’s word for things.

I don’t present perfection in my posts, nor do I expect perfection from others. I don’t care about how “dumb” it is thought questions or information is (presented by me or others) because as far as I’m concerned it’s the cliché of if you don’t try, someone else will.

I do not believe there are “smoking guns” in science, nor, if it’s done properly, “smoke screens.” Similarly, I don’t claim the scientific process is perfect, but I don’t believe it’s falling to pieces either. Hopefully that clarifies some things , but if not, let the general trend continue.

Ad hominem! It has to do with one’s interests and prejudices/feelings.

• One appeals to others’ feelings to attract attention to and elicit agreement with their ideas!
• Manipulating others’ feelings is not employing logic!
• It does not make one’s argument stronger!
• Logical thinking never involves feelings!