How do we know more CO2 is causing warming?
What the science says...
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An enhanced greenhouse effect from CO2 has been confirmed by multiple lines of empirical evidence. |
Climate Myth...
Increasing CO2 has little to no effect
"While major green house gas H2O substantially warms the Earth, minor green house gases such as CO2 have little effect.... The 6-fold increase in hydrocarbon use since 1940 has had no noticeable effect on atmospheric temperature ... " (Environmental Effects of Increased Atmospheric Carbon Dioxide)
At-a-glance
To make a statement like, "minor greenhouse gases such as CO2 have little effect", is to ignore 160 years of science history. So let's look at who figured out the heat-trapping properties of carbon dioxide and when.
Experiments involving various gas mixtures had demonstrated the heat-trapping properties of water vapour, CO2 and methane in the 1850s. But those effects were yet to be quantified - there were no meaningful numbers. It was to be another 40 years before that happened.
Swedish scientist Svante Arrhenius (1859-1927) was the person who crunched the numbers. The results were presented in a remarkable paper, "On the Influence of Carbonic Acid in the Air upon the Temperature of the Ground", in 1896.
The many calculations in the 1896 paper include estimates of the amounts of CO2 increase or decrease required to drive the climate into a different state. One example used was the Hothouse climate of the Cenozoic, around 50 million years ago. Another was the glaciations of the last few hundred millennia.
To get a temperature rise of 8-9°C in the Arctic, Arrhenius calculated that CO2 levels would have to increase by 2.5 to 3 times 1890s levels. To lower the temperature 4–5°C to return to glacial conditions, he calculated a drop in CO2 was needed of 0.62-0.55 times 1890s levels.
We know CO2 levels in the 1890s from ice-core data. They were around 295 ppm. Let's do the sums. A reduction factor of 0.55 to 0.62 on 295 ppm gives 162.2-183.9 ppm. Modern ice-core measurements representing the past 800,000 years show that in glacial periods, CO2 levels fell to 170-180 ppm.
What we now know due to additional research since 1896 when Arrhenius worked on this, is that CO2 was an essential 'amplifying feedback'. That means changes triggered by long term, cyclic variations in Earth's orbit cause warming or cooling and CO2 release or entrapment in turn. Those changes in CO2 levels affected the strength of Earth's greenhouse effect. Changes in the strength of the greenhouse effect then completed the job of pushing conditions from interglacial to glacial - or vice-versa.
Arrhenius also made an important point regarding water vapour: "From observations made during balloon voyages, we know also that the distribution of the aqueous vapour may be very irregular, and different from the ideal mean distribution." This statement holds true today: water vapour is a greenhouse gas but because water exists in gas, liquid and solid forms in the atmosphere, it is continually cycling in and out of the air. It is distributed in a highly uneven fashion and is uncommon in the upper atmosphere. That's where it differs from CO2.
Once CO2 is up there, it's up there for a long time. As a consequence it has a pretty even distribution: 'well-mixed' is the term. As Arrhenius quantified all that time ago, once it's up there it constantly absorbs and re-radiates heat in all directions. That's why dumping 44 billion tons of it into our atmosphere in just one year (2019 - IPCC Sixth Assessment Report 2022) is a really bad idea.
Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!
Further details
Good scientific theories are said to have ‘predictive power’. In other words, armed only with a theory, we should be able to make predictions about a subject. If the theory’s any good, the predictions will come true.
Here’s an example: when the Periodic Table of the chemical elements was proposed in 1869, many elements were yet to be discovered. Using the theory behind the Periodic Table, the Russian chemist Dmitri Mendeleev was able to predict the properties of germanium, gallium and scandium prior to their discovery in 1886, 1875 and 1879 respectively. His predictions were found to be correct.
The effect on Earth's greenhouse effect of adding man-made CO2 is predicted in the theory of greenhouse gases. This theory was first proposed by Swedish scientist Svante Arrhenius in 1896, based on earlier work by Fourier, Foote and Tyndall. Many scientists have refined the theory since Arrhenius published his work in 1896. Nearly all have reached the same conclusion: if we increase the amount of greenhouse gases in the atmosphere, the Earth will warm up.
Where there is less agreement is with respect to the exact amount of warming. This issue is called 'climate sensitivity', the amount the temperatures will increase if CO2 is doubled from pre-industrial levels. Climate models have predicted the least temperature rise would be on average 1.65°C (2.97°F) , but upper estimates vary a lot, averaging 5.2°C (9.36°F). Current best estimates are for a rise of around 3°C (5.4°F), with a likely maximum of 4.5°C (8.1°F). A key reason for this range of outcomes is because of the large number of potential climate feedbacks and their variable interactions with one another. Put simply, some are much better understood than others.
What Goes Down…
The greenhouse effect works like this: Energy arrives from the sun in the form of visible light and ultraviolet radiation. The Earth then emits some of this energy as infrared radiation. Greenhouse gases in the atmosphere 'capture' some of this heat, then re-emit it in all directions - including back to the Earth's surface.
Through this process, CO2 and other greenhouse gases keep the Earth’s surface 33°Celsius (59.4°F) warmer than it would be without them. We have added 42% more CO2, and temperatures have gone up. There should be some evidence that links CO2 to the temperature rise.
So far, the average global temperature has gone up by more than 1 degrees C (1.9°F):
"According to an ongoing temperature analysis led by scientists at NASA’s Goddard Institute for Space Studies (GISS), the average global temperature on Earth has increased by at least 1.1° Celsius (1.9° Fahrenheit) since 1880. The majority of the warming has occurred since 1975, at a rate of roughly 0.15 to 0.20°C per decade."
The temperatures are going up, just like the theory predicted. But where’s the connection with CO2, or other greenhouse gases like methane, ozone or nitrous oxide?
The connection can be found in the spectrum of greenhouse radiation. Using high-resolution FTIR spectroscopy, we can measure the exact wavelengths of long-wave (infrared) radiation reaching the ground.
Figure 1: Spectrum of the greenhouse radiation measured at the surface. Greenhouse effect from water vapour is filtered out, showing the contributions of other greenhouse gases (Evans 2006).
Sure enough, we can see that CO2 is adding considerable warming, along with ozone (O3) and methane (CH4). This is called surface radiative forcing, and the measurements are part of the empirical evidence that CO2 is causing the warming.
...Must Go Up
How long has CO2 been contributing to increased warming? According to NASA, “Two-thirds of the warming has occurred since 1975”. Is there a reliable way to identify CO2’s influence on temperatures over that period?
There is: we can measure the wavelengths of long-wave radiation leaving the Earth (upward radiation). Satellites have recorded the Earth's outgoing radiation. We can examine the spectrum of upward long-wave radiation in 1970 and 1997 to see if there are changes.
Figure 2: Change in spectrum from 1970 to 1996 due to trace gases. 'Brightness temperature' indicates equivalent blackbody temperature (Harries et al. 2001).
This time, we see that during the period when temperatures increased the most, emissions of upward radiation have decreased through radiative trapping at exactly the same wavenumbers as they increased for downward radiation. The same greenhouse gases are identified: CO2, methane, ozone and so on.
The Empirical Evidence
As temperatures started to rise, scientists became more and more interested in the cause. Many theories were proposed. All save one have fallen by the wayside, discarded for lack of evidence. One theory alone has stood the test of time, strengthened by experiments.
We have known CO2 absorbs and re-emits longwave radiation, since the days of Foote, Tyndall and Arrhenius in the 19th Century. The theory of greenhouse gases predicts that if we increase the proportion of greenhouse gases, more warming will occur.
Scientists have measured the influence of CO2 on both incoming solar energy and outgoing long-wave radiation. Less longwave radiation is escaping to space at the specific wavelengths of greenhouse gases. Increased longwave radiation is measured at the surface of the Earth at the same wavelengths.
Last updated on 16 July 2023 by John Mason. View Archives
Concerning the fraudulent Ottmar Edenhofer quotation reproduced @211.
The quote appeared to be presented verbatum (bar a "..."?) in Simon Downing (2011) "World Empire and the Return of Jesus Christ." p338? (I note Tom Curtis @212 suggested the quote in this source was not identical to that presented @211. Sadly the google review I link to has limited personal useage so I cannot double-check.) The quote appears in the book as a referenced quote but unfortunately the page setting out this reference #1061 (page 515) is not available in the google review available. Or that was the message I took away before I overstayed my personal welcome in the google review. It would thus take a sight of p515 to be sure this was the source of the fraud, so if anyone has a copy of this book on their bookshelf....
MA Rodger @226, I consider the Downing quote to be a misquotation based on the fact that the selection shown in the search result shows the phrase "one has to free oneself" preceding the phrase "we redistribute", ie, the reverse of order in the actual quote. That may be a coincidence, but that is unlikely. Further, a fuller search string pushes Downing's book much further down the results (if it appears at all), which suggests Downing cannot have quoted the full passage verbatim.
#223 @Renaissance Man
"Reference follows:" - Where is the reference?
Your example graph (Population Explosion) demonstrates clearly why it is often a good idea to not start the y axis at 0. If you had done we would have to scroll up or down about 200 metres to see the whole thing. I think you would admit that is impractical?
When what you are attempting to convey is the _change_ in a value, filling the graph is the only reasonable choice. Padding the graph with unchanging values is in such situations misleading to the point (in many cases) of misinformation.
Turning to RM's graphing examples, his example plotting CO2 concentration with his two adjustements (@209) shows a number of obvious flaws.
Firstly, and most obviously, we may be interested in CO2 concentration quite independently of our interest in the Total Greenhouse Effect. That the graph of CO2 concentration (the Keeling curve) does not include the primary contributor to the Total Greenhouse Effect is, therefore, irrelevant to its usefulness. Indeed, if we are exclusively interested in the Total Greenhouse Effect, we are better plotting that, with changes to it, rather than only the CO2 concentration. Consequently, the best that can be said for RM's graph is he plotted the wrong value for what he was interested in.
Far worse, for the actual graph he plots, is that RM overstates the value of water vapour concentration in ppmv by nearly a factor of 4. The concentration of water vapour, averaged across the atmosphere, is about 4,000 ppmv, not the 15,000 ppmv shown by RM. The 15,000 ppmv is indeed a reasonable approximation of the average concentration of water vapour at the surface; but the radiative interaction that gives us the greenhouse effect does not occur exclusively (or even significantly) at the surface. Rather, it occurs at altitude, and unlike CO2, the concentration of water vapour falls rapidly with altitude:
(Note: graph is of model values, for actual observations see preceding two links.)
So, not only does RM grossly inflate the graph to obscure important detail by including the irrelevant (for most purposes) H2O concentration, but he then includes an inflated value of the H2O concentration.
Finally, if RM was interested in the Total Greenhouse Effect, he ought simply to have plotted the Total Greenhouse Effect. The contribution of H2O and CO2 to the Total Greenhouse Effect is not proportional to their concentration. Indeed, though H2O has a stronger greenhouse effect overall, it has a very much weaker effect per molecule. (That is partly because the H2O concentration is closer to radiative saturation, but mostly due to the lower, and hence much warmer altitudes from which H2O radiates to space.) Schmidt et al (2010) showed that circa 1990, of the Total Greenhouse Effect, CO2 contributes about 20%, gaseous H2O a further 50%, and H2O in the form of clouds an additional 25%, with the remainder being contributed by minor greenhouse gases.
For those unfamiliar with the term, the Total Greenhouse Effect is the difference between the "Thermal Up Surface" and the "Thermal Outgoing TOA" as shown on this energy balance graph from the IPCC AR5:
That is, by best modern estimate it is about 159 W/m^2, though Schmidt et al cite 155 W/m^2 from an earlier source.
Of that, about 3.38 W/m^2, or 2.125% is the increase in radiative forcing from all anthropogenic greenhouse gases. It is very likely that approximately 2% further is due to the increase in the H2O contribution that has resulted from the increase in temperature leading to an average increase in global mean water vapour concentration (as discussed by HK @224). Whichever is used, it is significantly more than the misleading 0.8% increase not shown due to poor scale choice in RM's fundamentally misleading preferred graph.
RM @223:
1) The most misleading aspect of the new sample graph is the heading, not the choice of window of the y-axis chosen.
2) While true that non-informed people often have a false assumption that graphs always include the origin, and can be misled by their false assumption. That can be partly countered by using of breakpoints in the graph as in this example:
Still better, it should be countered by better choice of sample graphs in education; and by always emphasizing that no graph interprets itself - that you always need to look at the axies, the units, heading and text associated with the graph to understand it. It should not be pandered to by choosing a y-axis window so large that the variation in the data cannot be seen.
3) There has been about an 80 ppmv increase in CO2 over the last fifty odd years, not 1.6 ppmv as you claim.
4) The claimed 15,000 ppmv of greenhouse gases is a furphy (see preceding post).
Tom @212: fwiw, the Edenhoffer quote translation is correct. But more importantly, thanks for demonstrating how the denialists use chery picked, out-of-context, and rearranged "quotation" to mislead.
Tom Curtis @227,
I think 'misquotation' understates the what appears in Downing (2011) "World Empire and the Return of Jesus Christ". It is a total misrepresentation of Edenhoffer. The sentence in Simon Downing (2011) runs as follows:-
As I say @226, the name of the reference [1061] is not available from the link so it may be that Downing is not responsible for the fraud. And within this quote from Downing, the Downing mis-quote, bar the lower-case 'w' and the two extra fullstops indicating missing text, it is identical to the (mis)quote presented by RenaissanceMan @210.
[PS] No accusations of fraud please.
MA Roger,
Would you agree that
is the real source of the objections we find discussing AGW and particularly how we propose to mitigate AGW?
RB - In my opinion, this is really only an objection to very small group, many conspiracy theorists etc. Letting data define our opinions is not something that comes very naturally to human, even scientists. I think for many, the predisposition to disbelieve global warming and then haunt denialist sites to reinforce the opinion is more socially driven - its not what my "tribe" believes in/ not what opinion-makers I follow says is true etc. But what then drives the opinion makers?
In this I think the issue is more about role of government. The right wing struggles to envisiage a solution that does not involve large government intervention - be it carbon tax (another no-no word), cap-and-trade schemes etc. International treaties are also difficult as soon as they involve obligations even if there is no wealth redistribution at international level. As stupid as it sounds, the logic of "solutions to this problem are incompatiable with my values, ergo problem must not exist", I think plays a very real role in this.
However, most US citizens I know are academics, mostly scientists, so I may be underestimating prevalence of "wealth redistribution" phobics. (I gather these people dont mind redistribution of wealth from masses to a few extremely wealthy men - perhaps the old communist bogeyman lives on in US psyche).
schaddenp@235: "In this I think the issue is more about role of government. The right wing struggles to envisiage a solution that does not involve large government intervention - be it carbon tax (another no-no word), cap-and-trade schemes etc."
Response: (snip) The obvious counterpart to that nasty "right wing" is the "left wing" which almost undoubtedly would elicit a warning from the moderator, who brooks no discouraging word of any left wingers. But right wingers are chastized instantly.
" As stupid as it sounds, the logic of "solutions to this problem are incompatiable with my values, ergo problem must not exist", I think plays a very real role in this."
Response: (snip) The logic of "don't take away our billions of research dollars" and the profound left-wing bias of contemporary academia likewise plays a very real role.
"However, most US citizens I know are academics, mostly scientists, so I may be underestimating prevalence of "wealth redistribution" phobics. (I gather these people dont mind redistribution of wealth from masses to a few extremely wealthy men - perhaps the old communist bogeyman lives on in US psyche)."
Response: (snip) "Wealth redistribution" is part and parcel of the left wing obsession of characterizing that "right wing" as greedy, mean-spirited, and completely uncaring about "the poor." On that topic, the book by a former liberal and college professor, titled Who Really Cares, shows that the left wing does not practice what it preaches. In other words, left wingers give less of everything, to everyone than the right wing.
The final sentence written by schaddenp is socialist down to its core, claiming that the rich got that way by taking from the poor. It isn't remotely true, as proven throughout history. But the left wing never learns.
[RH] You can't seem to figure out the commenting rules. And, no, they're not being only applied to you. If you read carefully, the rules are being applied equally to all commenters.
I think you're on your last and final warning at this point.
[PS]@223: "The point of graphing is illustrate the data to maximum effect in the context."
The "context" of the Keeling Curve, as he presented it, is to emphasize the increase in atmospheric carbon dioxide.
By so making such an emphatic presentation, he utterly destroyed any perspective of the place of carbon dioxide vis a vis the total panoply of greenhouse gases, most particularly water vapor.
My graph demonstrates "maximum effect" of the "population explosion."
(snip) It "fills the page." I made it so to show the dishonesty of such exaggeration, like that of the Keeling Curve.
[RH] Again, no accusations of dishonesty are allowed in these comment forums. How hard is that to understand?
Now beyond final warning. All further comments will be deleted.
The following is a brief presentation of my model for calculating the daily heating contribution of carbon dioxide. There are 3 features of the model:
1) Concentration Coefficient: (ppmv) of CO2 compared to (ppmv) water vapor. Using the Ideal Gas Law, the dry composition of N2, O2, Ar and CO2, the local temperature, pressure and absolute humidity values this ratio varies. On average it is 0.05
2) Heat Absorption Coefficient: the absorption spectrum of carbon dioxide compared to the absorption spectrum of water vapor. This includes all heat radiated from the surface of the earth and heat radiated during the exothermic phase changes of water, including solidification, condensation, and deposition. These wavelengths include 19.9, 2.9 and 2.6 micrometers respectively. Both carbon dioxide and water vapor have peak absorption wavelengths near these wavelengths, as well the blackbody radiation given off by the earth has a very minute amount of this of both the 2.9 and 2.6 micrometer wavelengths. Recalculating the total absorption spectrum peaks and the energy under the curve for these peaks, I arrived at a total absorption energy of 3.0 x 10^-19 J/molecule of carbon dioxide in an excited state and 1.1 x 10^-18 J/molecule of water in an excited state. The Heat Absorption Coefficient becomes 0.27 for carbon dioxide compared to water.
3) Diffusion of Heat Coefficient: the rate that carbon dioxide transfers its heat compare to the rate that water vapor transfers its heat. Using Graham’s Law of effusion and the molar masses of Carbon dioxide and water, this coefficient is 0.64. As the greenhouse gas molecules trap heat, they must be able to transfer their heat to other molecules by making random collisions with the other molecules. The speed and efficiency at which they can do this will determine their “strength” as a greenhouse gas. Water vapor is lighter and moves more quickly than Carbon dioxide, if both are at the same temperature.
4) The total coefficient for the capacity of carbon dioxide to absorb and transfer heat compared to water is then 0.05 x 0.27 x 0.64 = .0086
When we look at the difference between the global average temperature and the blackbody temperature we arrive at 32.8 degrees C. So on an average humidity day, between 50 N. Latitude and 50 S. Latitude, the difference between the blackbody high, low, and average and the daily high, low and average will be 32.8 degrees C. Carbon Dioxide will account for .0086 x 32.8 degrees or .28 deg. C. This experiment is occurring daily, and it is an alternative to calculating the differences in Top of Atmosphere (TOA) and surface IR radiance. The issue with calculating this difference is that water vapor is continually undergoing exothermic phase changes that give off near IR and mid IR in the absorption ranges for both water vapor and carbon dioxide. Near the surface, the water vapor and carbon dioxide molecules will absorb and re-emit these frequencies. The problem is that liquid water droplets in clouds can absorb the 15 micrometer waves and thus stop the wave from traveling from the surface to the TOA. It would be very difficult to measure the radiance of this and calculate how what CO2 absorbed and what water droplets in the clouds absorbed or surface water absorbed as down welling radiation is absorbed by the surface water.
The argument that CO2 is more concentrated at higher altitudes cannot be used to support more heat being trapped here. There will be very upwelling in the little peak wavelengths that carbon dioxide absorbs, and almost no downwelling peak wavelengths. Carbon dioxide molecules at this altitude, provided the density separation does not result in a near extinction, will actually be radiators of heat. At this altitude, there are more possible vector directions that point to space, than point back to the surface. So as excited carbon dioxide molecules spontaneously radiate photons, there will be a more favorable amount of heat loss than heat gain by the climate. These higher altitude molecules cannot hold on to any trapped energy for an indefinite amount of time. Nothing can do that. Everything radiates its heat to the colder gradient as a necessity of the 2nd law of thermodynamics. CO2 at the TOA is not going to collect more heat than it radiates.
In summary, water is more efficient at trapping heat than carbon dioxide, by a factor of nearly 120 to one. The reason is that there are more molecules of water vapor to collide with the other 992,000 ppmv of non-greenhouse gases, and they can absorb more heat than CO2, and they can move faster than CO2 in order to transfer their heat to the other non-greenhouse molecules. It is painfully obvious that water vapor is most significant greenhouse molecule. Besides that, water must give off heat when it freezes, or condenses or undergoes deposition. When we get massive snowstorms, or rain storms or large areas of Arctic winter time freezing, then we must get rid of heat from the environment. If the rate of condensation in a cloud is equal to the rate of evaporation, then the droplets of water will never get large enough to fall from the sky; Hail stones would not fall from the sky in the summer if heat was not escaping the climate. Waves at the surface of the ocean break and create droplets of mist that come back down and rejoin with the ocean. It took energy to break the hydrogen bonds in order to create the mist. When the mist returns to the surface of the water, it reforms hydrogen bonds and photon of ER are given of in the 79 micrometer range. There is nothing to capture these photons and so the earth cools that way. Water is the great climate regulator and CO2 is responsible for a small fraction of the heating. Experiments measuring downwelling against upwelling of the peak wavelengths of carbon dioxide are not able to distinguish where the wavelengths were absorbed. Liquid water also absorbs these peak 15 micrometer waves that CO2 absorbs. Therefore we cannot attribute the absence of these 15 micrometer waves as a result of CO2 blocking the upwelling radiation totally out. Liquid water blocks some. A better way to measure the effects that CO2 has on trapping heat, is to measure use the final coefficient as described in my model.
From my model, the temperature rise is .0007 deg. C/ppmv CO2. When we double the CO2 values, the temperature will rise .57 deg. C.
Rudmop,
Can you suggest to me two reasons why I should accept the conclusion of a random guy on the internet instead of the conclusions of scientists who have worked on this problem for over 100 years? Have you tried getting your model peer reviewed so that you can see what professionals think of your work? Have you compared your model to the professional models available on the internet that Tom Curtis linked for you? Professional scientists say that the upper atmosphere is the key location for the greenhouse effect but you claim that it is not important. Seems to me like one side has a gross error. Are you claiming all the scientists in the world are incorrect but you are correct?
michael sweet,
In science, there is no benefit to be had by forcing the validity of a clearly presented model down the throat of other scientists. Science does not work by one scientist or a group of scientists forcing people to accept a clearly thought out model. My model is steeped in thermodynamics and KMT, as well as quantum mechanics. My model does not violate any of the laws, and it serves as an alternative answer to a model that has failed on its predictions. What is unique about it, is that it considers the climate soup we wallow in on the surface. It considers the direct and frequent measurements we take globally and precisely on our weather stations. My model has no need to consider downwelling and upwelling IR photons, because it uses the results of their influence on the climate to calculate the effect of CO2 as a greenhouse gas. So there is no need for me to give you two reasons or a hundred reasons of why I need to convince you to accept anything. I trust that you are a scientifically literate person. I trust if you know and understand the laws of Thermodynamics and Quantum Mechanics. You will be able to convince yourself of the validity of any scientific model that any scientist presents. When the science illiterates try to force their beliefs and views to force others to adopt these views, then they will lose any credibility they had hoped of having. True scientists don’t have beliefs and don’t have to force others to believe. True scientists also understand the potential of presenting a false model and expecting other scientists to dignify their credibility. As a scientist, all I have is a successful patent on a cleaner that is unique like no other, a science degree in Biology with a chemistry minor and a Master of Arts in Secondary Education. I am credentialed in the Life Sciences, Chemistry, Physics, the Geosciences and I have taught school for 26 years in subjects ranging from 7th grade life science to High School Advanced Placement Chemistry and Physics; Currently I teach Aerospace Engineering, 8th grade Physical Science, Physics and Advanced Placement Physics. Besides researching and learning the Standard Model of Particle Physics, and the probable working of Quantum mechanics, I enjoy reading science Journals that arrive from AAPT and ACS, of which I am a member. As well, I like to turn nuts and bolts in my free time. I enjoy fixing stuff when it breaks, like the plumbing, air conditioner and the mechanical stuff on my hybrid car. I’m simply saying besides being a professional in my field, I understand a bit about the world.
Rudmop @238.
So what you are saying is that the amount of radiation absorbed by CO2 and transferred to the atmosphere immediately surrounding it (thus its GHG function) can be usefully compared with the amount absorbed by water vapour. This Ratio(CO2:H2O), you say is the product of three factors:-
Ratio(CO2:H2O) = A x B x C
where A = the average volume ratio of the two gases in the atmosphere, B = the ratio of the blackbody radiation occuring at the wavelengths absorbed by the two gases, and C = the number of collisions made by a molecule of each two gases and the energy thus transferred. You calculate Ratio((CO2:H2O) = 0.0086.
From this you conclude that if the global surface temperature is 32.8ºC above the blackbody temperature, the warming contribution of CO2 in the atmosphere is 32.8 x 0.0086 = 0.28ºC.
To this finding you add the caviat that clouds add a complication to a simplistic use of this ratio. You also mention the altitude profile of CO2 not being a factor (although I was unaware of there being such a profile of any significance – eg see Foucher et al 2011). You do fail to mention a whole bunch of other stuff which will prevent the use of such a simplistic analysis, stuff which all others have considered which is why they don't attempt what you are doing here.
@239, your comment "When we double the CO2 values, the temperature will rise .57 deg. C." is presumably describing the total CO2 warming resulting from a CO2 concentration of 550ppm relative to 0ppm. (Note the accepted extra primary warming from a doubling of CO2 (eg 275ppm to 550ppm) is currently given as 1ºC which is greatly different from your 0.28ºC fixed for all 275ppm rises.)
@241 you present what I consider a misguided appreciation of science along with your credentials which are an irrelevance. You say that you “understand a bit about the world” but I do wonder if your understanding is of a bit that isn't useful to this analysis you perform here.
Rudmop @241 states:
The models (plural) that Rudmop claims to have failed are the Line By Line (LBL), or lower resolution radiation models (or the modules within GCMs that serve the same function). It is they, not GCMs as a whole that determine relative contribution to the Total Greenhouse Effect of various gases. These models have produced such obviously failed predictions as this one from 1969:
Or these (all 134,862 of them) from 2008:
Here is the preceding data binned by surface temperature (a) and latitude (b):
In contrast to the LBL models, which predict easilly discriminable data for clear comparison with reality, Rudmop's model does not predict any observable quantity. Rather, it only predicts a quantity that cannot be directly observed. That is, its only prediction is not falsifiable by direct observation.
It can be known to be wrong, however, because the LBL radiation models with their copious directly observable predictions, which are falsifiable but unfalsified, also make predictions about the value which is the sole prediction of Rudmop's model.
It is no wonder he wants to take his model before an uninformed public rather than to a group of experts in the field. It is hard to hoodwink those who know what they are talking about.
Sorry I don't have time for sarcastic retorts that attack my character, as well it is against the rules of the site which hats scientific discussion. I have provided a clear explanation of my model. There is an expectation that you will not use conflation as a means to invalidate it. It stands own as far as the science. So unless you can address where it fails, without using tactics of insults and conflation, I trust that anyone who views this as a credible means to invalidate my model will know what that type of behavior clouds their scientific reputation. It is not how scientific discussions progress. Good day.
Rudmop... I'm curious. If you genuinely believe you have a model that substantively challenges the standard accepted model, why are you posting it here? If I had worked out such a thing I'd be submitting it to major scientific journals. And after that I'd be out shopping for the tux I'd need for my Nobel acceptance speech.
Yes, I know that sounds like a sarcastic comment, but that is the gist of what you're offering up. You're challenging basic physics which has been well understood and accepted for 150 years.
As a non-scientist I can already pick out several basic errors in your comment. But it seems counter-productive to go into those details being that the overall notion you're presenting is so utterly preposterous.
But you are correct to essentially suggest that all ideas should be entertained. So, for entertainment purposes... can you please paste in here your calculations? You know, something along the lines of this.
Rudmop... "I have provided a clear explanation of my model."
Not so much. You've written a rambling piece, that doesn't have any substantive math, and runs contrary to basic physics.
Rudmop... "I trust that anyone who views this as a credible means to invalidate my model will know what that type of behavior clouds their scientific reputation. It is not how scientific discussions progress."
If you give us the math that shows your model, people here can evaluate it.
Further re Rudmop, here is a fuller version of the first comparison in my preceding post, with the data offset for easy comparison:
In reading such graphs, as a simple rule, a molecule traps an amount of energy per second cm-1 steradian-1 equal to the difference between the observed radiation at that wavenumber and the black body radiation of the surface. As can be seen, the 15 μ-meter wavelength (667 cm-1 wavenumber) is deep and distinct, unlike the neighbouring absorption by H2O.
Second, the effective altitude of radiation within the troposphere can be determined as approximately the difference between the radiation temperature and that of the black body at the surface, divided by the lapse rate. Thus the "shoulders" of the CO2 absorption band show absorption at about 12 km, while the neighbouring H2O shows absorption at an effective altitude of 6 km or less. That difference is the fundamental difference that makes CO2 absorption more effective per molecule than is H2O absorption.
Both of these features are features Rudmop claims are false.
I have submitted it to a scientific journal on Feb 21, 2016. I am also ready for talks.. I probably am going about giving up a lot, but to date, no one has shown this in the literature, except me here on this discussion blog for climate scientists. I will be giving a presentation at Occidental college tomorrow on my model here. I. In my submission t have done the math and provided the equations, with my own variables. I prefer zeta and and kapparently for my coefients. I explain my calculations an the resonance absorption frequencies that cause an excited molecule in a state of super position. I appreciate the efforts of those scientists who have given me rational food for though for my presentation. My less egocentric psyche did warn me about the possibility of giving away my ideas, however if there is a Nobel prize to be given for this, I have only disclosed the part, it takes much more that I will not present here and show the proof. If that is the case that my model is worth a Nobel prize, this important part is the half of it. The other half will be in the book and the article.
That submittal date is 2017, sorry. I cannot read my post as I type on my phone. Need to wait until this evening when I can access my computer.