Climate modeling and decision milestones

[skydelph]

Our view on climate change, the point where we are today and predictions are the result of scientific breakthroughs, steady developments and of course technological leaps.

All of the above components are the keys for the climate models, upon which we fully rely.

Firstly, I would like to share a link, which is different from popular climate change and modeling discussions with its analysis approach.

https://medium.com/our-changing-climate/climate-modelling-from-manabe-and-wetherald-to-supercomputer-jasmin-1c8d5d11431b

My second point would be human impact and actions planned and being done for the nearest future. Net zero 2050 might be unrealistic. But there should be a reasonable deadline, to sharpen international initiatives and economies. Even if a lot of plans exist only on paper or contradict the budgets, even environmentally unfriendly infrastructure cannot stop in that short period.

My third point would be that climate changing is not only about emissions, models and personal carbon print. The whole technology and knowledge, which is  in our hand should be used to follow the 2050 deadline, including space manufacturers, dedicated to global changes and local ecosystems monitoring as well as data sharing.

[Doogles31731]

skydelph, thank you for that reference to Manabe's 1960s work on climate.

I've personally searched the literature for early BASIC studies on the measurable absorption and radiation properties of infrared radiation by carbon dioxide gas and so far, have only found the work by Tyndall in the 1860s. Tyndall of course only used a can of hot water and a galvanometer, and recorded the degree of deflection of the galvanometer needle for a variety of gases. He did not measure the effect of carbon dioxide on its own; he used air that had been passed through solutions to remove moisture and carbon dioxide, and then he measured the deflection caused by his untreated laboratory air. He attributed the difference to what he believed was a combination of water vapour and carbon dioxide and labelled this deflection as being due to "carbonic acid". At least, that's the way I interpreted his experiments.

My question to you is whether you have come across a reference from Manabe's era that involved a BASIC study of the absorption and radiation properties of heat (or infrared) by carbon dioxide alone, for use in modelling. I have been unsuccessful in my search.  

[Doogles31731]

My question above applies to anybody else in this forum.

The reference cited by skydelph simply states in part "To test the model, Manabe decided to change levels of various greenhouse gases, such as carbon dioxide, to see what impact this had on the Earth’s temperature. The results were remarkable. Taking out all of the greenhouse gases from the atmosphere reduced the planet’s temperature by 30C. Conversely, raising levels of greenhouse gases dramatically increased temperatures."

There had to be some basic research associating concentrations of carbon dioxide gases with temperatures, for variations of greenhouse gases to become meaningful in Manabe's models. Tyndall's work did not go that far.

I have asked that question in another forum that has since folded, but NOBODY has been able to provide me with such a reference. I received plenty of references to variations in wavelengths at which carbon dioxide could be detected, but these were irrelevant. The basic work that Manabe relied upon would have to be dated pre-1960s. 

 

 

[CharonY]

Details of the model should be in the manuscript, and by skimming the references these look promising:

-  Kaplan 1960, Tellus 12,204-208

- Manabe and Moeller 1961, Mon. Wea. Rev. 89,503-532

- Moeller 1963, J Geophys Res 68,3877-3886

- Plass 1957, Quart J Roy Meteor Soc 82,310-324

[exchemist]

On 1/26/2022 at 9:04 PM, Doogles31731 said:

skydelph, thank you for that reference to Manabe's 1960s work on climate.

I've personally searched the literature for early BASIC studies on the measurable absorption and radiation properties of infrared radiation by carbon dioxide gas and so far, have only found the work by Tyndall in the 1860s. Tyndall of course only used a can of hot water and a galvanometer, and recorded the degree of deflection of the galvanometer needle for a variety of gases. He did not measure the effect of carbon dioxide on its own; he used air that had been passed through solutions to remove moisture and carbon dioxide, and then he measured the deflection caused by his untreated laboratory air. He attributed the difference to what he believed was a combination of water vapour and carbon dioxide and labelled this deflection as being due to "carbonic acid". At least, that's the way I interpreted his experiments.

My question to you is whether you have come across a reference from Manabe's era that involved a BASIC study of the absorption and radiation properties of heat (or infrared) by carbon dioxide alone, for use in modelling. I have been unsuccessful in my search.  

I think the IR spectrum of CO2 is well characterised, isn’t it? So from that one can presumably model things from what radiation a given concentration of CO2 over a given path length would be expected to absorb. Or are you after how the model was constructed?

[Doogles31731]

CharonY - Thank you for those references. I couldn't find a reference list associated with the link in the OP, but I did screed through your suggestions. I copied and pasted them as you listed them into Google Scholar. Some of the results that appeared, seemed  to have no relevance to what I'd typed in. In one case (Plass 1957), Google Scholar brought up a full article by Manabe and Wetherall.  It had a reference list that contained a possible couple of leads, so I'll work back from them over the next few days. Although I haven't found a really basic experimental project yet, I'm optimistic. Thank you.

exchemist, thank you for your response. Yes, the IR spectrum of CO2 is well characterised. But what I'm looking for is the basic controllable laboratory experiment that measures the absorption of infrared radiation by varying concentrations of CO2 gas. I would love to see a graph showing changes in degree of absorption with changes of concentration.

There seems to be an assumption that it is linear, but there is another school of thought suggesting that the degree of absorption decreases with increasing concentrations of CO2. I would like to see the man basic work on which current models are based, but to date I haven't succeeded. 

[CharonY]

7 hours ago, Doogles31731 said:

CharonY - Thank you for those references. I couldn't find a reference list associated with the link in the OP, but I did screed through your suggestions. I copied and pasted them as you listed them into Google Scholar. Some of the results that appeared, seemed  to have no relevance to what I'd typed in. In one case (Plass 1957), Google Scholar brought up a full article by Manabe and Wetherall.  It had a reference list that contained a possible couple of leads, so I'll work back from them over the next few days. Although I haven't found a really basic experimental project yet, I'm optimistic. Thank you.

It is likely that they are a bit hard to find, I copied the references from a pdf found via web of science. I have tracked down two DOIs that at least seem most closely related to your question (and they point to the missing ones), but I did not really spend time reading them.

https://doi.org/10.1175/1520-0493(1961)089<0503:OTREAH>2.0.CO;2

https://doi.org/10.1029/JZ068i013p03877

 

 

[exchemist]

9 hours ago, Doogles31731 said:

CharonY - Thank you for those references. I couldn't find a reference list associated with the link in the OP, but I did screed through your suggestions. I copied and pasted them as you listed them into Google Scholar. Some of the results that appeared, seemed  to have no relevance to what I'd typed in. In one case (Plass 1957), Google Scholar brought up a full article by Manabe and Wetherall.  It had a reference list that contained a possible couple of leads, so I'll work back from them over the next few days. Although I haven't found a really basic experimental project yet, I'm optimistic. Thank you.

exchemist, thank you for your response. Yes, the IR spectrum of CO2 is well characterised. But what I'm looking for is the basic controllable laboratory experiment that measures the absorption of infrared radiation by varying concentrations of CO2 gas. I would love to see a graph showing changes in degree of absorption with changes of concentration.

There seems to be an assumption that it is linear, but there is another school of thought suggesting that the degree of absorption decreases with increasing concentrations of CO2. I would like to see the man basic work on which current models are based, but to date I haven't succeeded. 

Do you mean this sort of thing?: 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6174548/

[Doogles31731]

Firstly exchemist -- Once again thanks for the help. I had seen that recent paper about variations of CO2 absorption across the troposphere, but what I'm looking for is the very first study (after Tyndall) that anybody made to incriminate CO2 changes into Climate Change Theory.

CharonY, thanks again for the leads. The first website is a full text and contains a 1955 reference that I'll have a look at over the weekend. I'm off to the gym now. As you can see, the reference dates are becoming earlier, and that is my hope and expectation. It seems a good lead. I had seen the second reference yesterday when I checked your list of refs yesterday. The last sentence of the Abstract intrigued me -- "The effect of an increase in CO₂ from 300 to 330 ppm can be compensated for completely by a change in the water vapor content of 3 per cent or by a change in the cloudiness of 1 per cent of its value without the occurrence of temperature changes at all. Thus the theory that climatic variations are effected by variations in the CO₂ content becomes very questionable."

[exchemist]

45 minutes ago, Doogles31731 said:

Firstly exchemist -- Once again thanks for the help. I had seen that recent paper about variations of CO2 absorption across the troposphere, but what I'm looking for is the very first study (after Tyndall) that anybody made to incriminate CO2 changes into Climate Change Theory.

CharonY, thanks again for the leads. The first website is a full text and contains a 1955 reference that I'll have a look at over the weekend. I'm off to the gym now. As you can see, the reference dates are becoming earlier, and that is my hope and expectation. It seems a good lead. I had seen the second reference yesterday when I checked your list of refs yesterday. The last sentence of the Abstract intrigued me -- "The effect of an increase in CO₂ from 300 to 330 ppm can be compensated for completely by a change in the water vapor content of 3 per cent or by a change in the cloudiness of 1 per cent of its value without the occurrence of temperature changes at all. Thus the theory that climatic variations are effected by variations in the CO₂ content becomes very questionable."

Ah now I see. Sorry, I was being a bit slow to catch on.  Arrhenius seems to have been the founding father, back in 1896:

https://iopscience.iop.org/article/10.1086/121158 though he was thinking about a decrease in CO2, inducing another ice age.

From what I read on Wiki it looks as if this idea fell by the wayside and was resurrected in the mid c.20th by Guy Stewart Callendar in 1938 and then by Charles David Keeling in the 1950s And then Manabe....... 

 https://en.wikipedia.org/wiki/History_of_climate_change_science#cite_note-43.

But no doubt you've already followed up all the references from there.  

 

Edited January 28, 2022 by exchemist

[Doogles31731]

Thanks again exchemist. That reference to Guy Stewart Callendar (1938) looked promising but unfortunately it's part of a book and not available as a reference.

I was able to find a couple of more early references.  Plass GN (1955: https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.2153-3490.1956.tb01206.x) in The Carbon Dioxide Theory of Climatic Change. This paper looked promising, but it turned out to be a calculation based on the data from what he called the accurate laboratory experiments of Cloud (1952). Unfortunately, a copy and paste of that reference into Google Scholar and PubMed did not produce the reference.

The Introduction to Plass’ paper indicated that the science available at that time was anything but generally accepted and consensual.  He cited “In 1861,TYNDALL wrote that “if, as the above experiments indicated, the chief influence be exercised by the aqueous vapour, every variation of this constituent must produce a change of climate. Similar remarks would apply to the carbonic acid diffused through   the air. ... “

Plass went on to state that the feeling at the time he published the above paper, was that water vapour may be the main driver of climate change. It absorbs wavelengths from 4 to 80 micron, but with a strong effect in the wavelengths absorbed by CO2. See  http://www.ces.fau.edu/nasa/module-2/how-greenhouse-effect-works.php.

As I said, Plass cited the following reference as his basic source of facts about CO2 and temperatures for his calculations -- CLOUD, W. H., 1952: The 15 micron  band  of CO, broadened by nitrogen and helium. ONR Progress Report. Unfortunately The reference did not come up in Google Scholar or PubMed.

Any ideas?

 

[exchemist]

52 minutes ago, Doogles31731 said:

Thanks again exchemist. That reference to Guy Stewart Callendar (1938) looked promising but unfortunately it's part of a book and not available as a reference.

I was able to find a couple of more early references.  Plass GN (1955: https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.2153-3490.1956.tb01206.x) in The Carbon Dioxide Theory of Climatic Change. This paper looked promising, but it turned out to be a calculation based on the data from what he called the accurate laboratory experiments of Cloud (1952). Unfortunately, a copy and paste of that reference into Google Scholar and PubMed did not produce the reference.

The Introduction to Plass’ paper indicated that the science available at that time was anything but generally accepted and consensual.  He cited “In 1861,TYNDALL wrote that “if, as the above experiments indicated, the chief influence be exercised by the aqueous vapour, every variation of this constituent must produce a change of climate. Similar remarks would apply to the carbonic acid diffused through   the air. ... “

Plass went on to state that the feeling at the time he published the above paper, was that water vapour may be the main driver of climate change. It absorbs wavelengths from 4 to 80 micron, but with a strong effect in the wavelengths absorbed by CO2. See  http://www.ces.fau.edu/nasa/module-2/how-greenhouse-effect-works.php.

As I said, Plass cited the following reference as his basic source of facts about CO2 and temperatures for his calculations -- CLOUD, W. H., 1952: The 15 micron  band  of CO, broadened by nitrogen and helium. ONR Progress Report. Unfortunately The reference did not come up in Google Scholar or PubMed.

Any ideas?

 

Hmm, I see. Re water vapour, I had always thought it was generally recognised that this is the main greenhouse gas in the atmosphere, but that as the amount is fairly self-regulating it does not lead on its own to a change, whereas it is the CO2 that is changing. In fact I think I have read that one effect of temperature increase due to CO2 is that the amount of water vapour goes up in consequence (not surprisingly, as the sea warms), thereby acting as an amplifier.

Tell me, is it early experimental work you are looking for, specifically, or just early attempts at modelling the effect of CO2 on climate?  

Addendum: I've found a link to Callendar's paper, here, but it only shows the abstract: you have to buy it to read the whole thing: https://rmets.onlinelibrary.wiley.com/doi/abs/10.1002/qj.49706427503

I found this from a site called "Carbon Brief" which  has a nice timeline you can click on to see various milestones:

https://www.carbonbrief.org/timeline-history-climate-modelling

 I notice also a reference to a  Mikhail Budyko, in 1956, which looks as if it might be relevant, but there are others mentioned too which might be worth a look.

Edited January 29, 2022 by exchemist

[TheVat]

CO2 has been thoroughly examined by physical chemists via spectroscopy, and its interaction with a variety of forms of energy has been excruciatingly examined by a number of scientists and groups.

One example of this being the Air Force Geophysics Laboratory, in Hanscom MA. Back in the 1950’s (a century after Eunice Foote’s and John Tyndall's work) the Air Force had a problem; the newly developed technology of “heat seeking missiles” did not work. They could not distinguish hot targets from the ambient IR in the atmosphere due to CO2 and other greenhouse gasses. This forced the geophysicists and geochemists at the laboratory to rigorously document not only the magnitude of IR downwelling caused by CO2 and other greenhouse gasses but the precise wavelengths and properties of the IR interactions of those gases. Having conducted a rigorous campaign of observations and testing, the sensors on those heat seeking missiles were redesigned to ignore the specific IR wavelengths CO2 and other greenhouse gasses re-emitted so that they could actually function.

Here is a good review, including spectral data from Earth and also Mars and Venus:

 

https://geosci.uchicago.edu/~rtp1/papers/PhysTodayRT2011.pdf

As others note, it is water vapor that amplifies the GH effect of CO2, something I pointed out to you, @Doogles31731, on my old science forum.  

[Doogles31731]

exchemist, I really appreciate your positive assistance. It is early basic experimental work I’m looking for. I rationalize that if someone is going to do modelling or calculations that involve the effects of CO2 concentrations on atmospheric warming, then they need some basic experimental laboratory quality controlled data to start with.

So far, the best lead I’ve come across is the Plass’ reference of ‘CLOUD, W. H., 1952: The 15 micron  band  of CO, broadened by nitrogen and helium. ONR Progress Report.’ He described it as “recent accurate laboratory measurements of the absorption in the CO2 band by CLOUD (1952).” But as I said, the link does not work.

That abstract by Callendar sounds a possibility, thank you. I will get a full text, so I may be quiet for a day or two. I see where Callendar’s work gets a mention as a seminal paper in the second link you provided.

...................................................................................

Yes, TheVat, we’ve been through all of this before. I guess you and I have different personal attitudes to science. You appear to be a consensus supporter, but I constantly question the validity of many scientific ideas. I fully understand the theoretical relationship expounded in the article you provided about how increasing CO2 concentrations lead to more water vapour and therefore more heat retention, but it doesn’t help in my search for the most basic experiment on the infrared absorption properties of varying concentrations of CO2. There is nothing in the reference list of that article suggesting a basic experiment.

If the basic science is so good, why do we have so many variations in predictions of ‘climate sensitivity’ by climate scientists? As you can see from the graph, the estimates have varied maybe 25-fold since 2000.

 

All of the calculations and models on the subject, by people such as Plass and Manabe, have to be based on some basic experimental data associating variations in absorption with varying concentrations of CO2. That’s what I’m looking for.

I felt as if I was getting close with the reference to Cloud (1952)

My problem is that I do not get any hits in Google Scholar or PubMed when I type the reference listed by Plass into the search boxes. Can you help with that problem?

 

 

 

[TheVat]

1 hour ago, Doogles31731 said:

 

Yes, TheVat, we’ve been through all of this before. I guess you and I have different personal attitudes to science. You appear to be a consensus supporter, but I constantly question the validity of many scientific ideas. I fully understand the theoretical relationship expounded in the article you provided about how increasing CO2 concentrations lead to more water vapour and therefore more heat retention, but it doesn’t help in my search for the most basic experiment on the infrared absorption properties of varying concentrations of CO2. There is nothing in the reference list of that article suggesting a basic experiment.

 

 I'm a fact supporter, period.  If you were interested in basic experiments, and data from such, then perhaps you followed up on the US Air Force Geophysical Laboratory lead I offered.  I don't have links to whatever they documented, but I feel it is pretty likely they did the kind of research you seek.  

 

[exchemist]

10 hours ago, Doogles31731 said:

exchemist, I really appreciate your positive assistance. It is early basic experimental work I’m looking for. I rationalize that if someone is going to do modelling or calculations that involve the effects of CO2 concentrations on atmospheric warming, then they need some basic experimental laboratory quality controlled data to start with.

So far, the best lead I’ve come across is the Plass’ reference of ‘CLOUD, W. H., 1952: The 15 micron  band  of CO, broadened by nitrogen and helium. ONR Progress Report.’ He described it as “recent accurate laboratory measurements of the absorption in the CO2 band by CLOUD (1952).” But as I said, the link does not work.

That abstract by Callendar sounds a possibility, thank you. I will get a full text, so I may be quiet for a day or two. I see where Callendar’s work gets a mention as a seminal paper in the second link you provided.

...................................................................................

Yes, TheVat, we’ve been through all of this before. I guess you and I have different personal attitudes to science. You appear to be a consensus supporter, but I constantly question the validity of many scientific ideas. I fully understand the theoretical relationship expounded in the article you provided about how increasing CO2 concentrations lead to more water vapour and therefore more heat retention, but it doesn’t help in my search for the most basic experiment on the infrared absorption properties of varying concentrations of CO2. There is nothing in the reference list of that article suggesting a basic experiment.

If the basic science is so good, why do we have so many variations in predictions of ‘climate sensitivity’ by climate scientists? As you can see from the graph, the estimates have varied maybe 25-fold since 2000.

 

All of the calculations and models on the subject, by people such as Plass and Manabe, have to be based on some basic experimental data associating variations in absorption with varying concentrations of CO2. That’s what I’m looking for.

I felt as if I was getting close with the reference to Cloud (1952)

My problem is that I do not get any hits in Google Scholar or PubMed when I type the reference listed by Plass into the search boxes. Can you help with that problem?

 

 

 

Good luck with Callendar. I hope it is useful. 

But thinking more about your response, I find myself wondering what sort of experimental work you are hoping to find. I don't profess any expertise in this field, but I'd have thought that the principal challenge is in the modelling of the climate, rather than in gathering data on CO2.  Once you have the molar attenuation coefficient of CO2 as a function of wavelength, i.e. a well-characterised absorption spectrum (which is well known), I imagine the other data inputs on CO2 that you need are its concentration, perhaps as a function of altitude, and then it's matter of putting that into the mix with all the other horrendously complex factors to do with radiation intensity, albedo, the effect of the oceans and so on and so on, none of which involve CO2 per se.

So what further experimental data on CO2 are you thinking would be needed?

As for the comments on the variation between models, I'm not sure that is surprising, bearing in mind the complexity of the modelling. But I note we have convergence, rather divergence, which seems to suggest the modelling process is likely to be valid, plus of course 20 years more of actual experience of climate change since the start of the graph, against which to judge the models.  

Edited January 30, 2022 by exchemist

[Doogles31731]

Thank you once again to those who sent me responses and links to research.

I assure you that I read every link that comes up with an original research article and I carefully go through the reference lists for what I am looking for. I do not follow up references to books or second hand popular journal interpretations.

I uploaded a graph of publications on climate sensitivity in my last post. It demonstrated the various figures calculated by many reearch groups over the last 20 years for predicted near-surface temperatures if the CO2 concentration was doubled in the atmosphere. This is labelled ‘Climate Sensitivity’. There is a 25-fold difference (not 25%; 25-fold) between their calculations of what the near-surface average global temperature rise would be.

Because there is such a wide variation in these predictions, I began to suspect that there is something wrong with the basic science on climate change. 

There are other reasons as well of course, but that one example is enough in its own right for me to become curious about the basics. I apologize to anybody if such a search makes them feel uncomfortable about their own belief systems in what they choose to accept. I’m personally curious as to why, after 160-odd years, we have not yet achieved anywhere near conformity in agreement as to what our near-surface temperature would be if we doubled carbon dioxide concentrations. A one-fold difference may be acceptable, but a 25-fold range from top to bottom??? I assume the results were from peer-reviewed journals.

So getting on with Callendar (1938), thanks to exchemist, it’s a good paper, and I can understand why it was listed by the Wikipedia researcher as one of the significant papers in the history of Climate Change science. Callendar has produced a graph of temperature anomalies associated with varying concentrations of CO2 in the atmosphere. His graph indicates that a change from 300 to 400 ppm (dry air) would result in an increase of 1 degree C or so, which is about what happened over the last 100 years.

But his results once again were mostly calculations, based, as he said, on the work of Rubens and Aschkinass (1898), Rubens and Hettner (1918) and Fowle (1918).

I will try to follow them up, but I’m pessimistic that such old papers will be available.

I’m getting the impression now that the science of Climate Change has developed piecemeal, with a sort of trial and error nature based on hypotheses and counter-hypotheses coupled with countless papers on atmospheric measurements of all kinds over a long period.

Following my search so far, my expectation now is that I’ll find that the only basic laboratory-controlled experiment in the field was that of Tyndall’s in the 1860s.  He used a can of hot water, a tube and a galvanometer to quantitatively assess the absorption (and radiation) of ‘heat’ by a variety of gases. It doesn’t look at this stage as if anybody has repeated his work using infrared lamps and spectrophotometers with a glass or perspex tube designed to hold a variety of pure or mixed gases at various temperatures and simulated atmospheric conditions, along with inserted thermometers and gas gauges. The design and manufacture of such a tube would probably be the biggest technical problem in a machine designed like an Atomic Absorption Spectrophotometer.

Special thanks to you exchemist. I realize that you had to go out of your way to obtain that Callender (1938) reference for me.

[exchemist]

5 minutes ago, Doogles31731 said:

Thank you once again to those who sent me responses and links to research.

I assure you that I read every link that comes up with an original research article and I carefully go through the reference lists for what I am looking for. I do not follow up references to books or second hand popular journal interpretations.

I uploaded a graph of publications on climate sensitivity in my last post. It demonstrated the various figures calculated by many reearch groups over the last 20 years for predicted near-surface temperatures if the CO2 concentration was doubled in the atmosphere. This is labelled ‘Climate Sensitivity’. There is a 25-fold difference (not 25%; 25-fold) between their calculations of what the near-surface average global temperature rise would be.

Because there is such a wide variation in these predictions, I began to suspect that there is something wrong with the basic science on climate change. 

There are other reasons as well of course, but that one example is enough in its own right for me to become curious about the basics. I apologize to anybody if such a search makes them feel uncomfortable about their own belief systems in what they choose to accept. I’m personally curious as to why, after 160-odd years, we have not yet achieved anywhere near conformity in agreement as to what our near-surface temperature would be if we doubled carbon dioxide concentrations. A one-fold difference may be acceptable, but a 25-fold range from top to bottom??? I assume the results were from peer-reviewed journals.

So getting on with Callendar (1938), thanks to exchemist, it’s a good paper, and I can understand why it was listed by the Wikipedia researcher as one of the significant papers in the history of Climate Change science. Callendar has produced a graph of temperature anomalies associated with varying concentrations of CO2 in the atmosphere. His graph indicates that a change from 300 to 400 ppm (dry air) would result in an increase of 1 degree C or so, which is about what happened over the last 100 years.

But his results once again were mostly calculations, based, as he said, on the work of Rubens and Aschkinass (1898), Rubens and Hettner (1918) and Fowle (1918).

I will try to follow them up, but I’m pessimistic that such old papers will be available.

I’m getting the impression now that the science of Climate Change has developed piecemeal, with a sort of trial and error nature based on hypotheses and counter-hypotheses coupled with countless papers on atmospheric measurements of all kinds over a long period.

Following my search so far, my expectation now is that I’ll find that the only basic laboratory-controlled experiment in the field was that of Tyndall’s in the 1860s.  He used a can of hot water, a tube and a galvanometer to quantitatively assess the absorption (and radiation) of ‘heat’ by a variety of gases. It doesn’t look at this stage as if anybody has repeated his work using infrared lamps and spectrophotometers with a glass or perspex tube designed to hold a variety of pure or mixed gases at various temperatures and simulated atmospheric conditions, along with inserted thermometers and gas gauges. The design and manufacture of such a tube would probably be the biggest technical problem in a machine designed like an Atomic Absorption Spectrophotometer.

Special thanks to you exchemist. I realize that you had to go out of your way to obtain that Callender (1938) reference for me.

Thanks. But would you mind answering my question, please? What further experimental work were you expecting to find, or do you consider there should be? Because It is not obvious to me that any more experiments would be needed, as the challenge is in the modelling, rather than in the well known properties of the gases involved.

Edited January 31, 2022 by exchemist

[John Cuthber]

On 1/26/2022 at 9:04 PM, Doogles31731 said:

I've personally searched the literature for early BASIC studies on the measurable absorption and radiation properties of infrared radiation by carbon dioxide gas and so far, have only found the work by Tyndall in the 1860s.

How hard did you look? The IR spectrum of CO2 is all over the web.
 

 

On 1/28/2022 at 8:20 AM, Doogles31731 said:

Yes, the IR spectrum of CO2 is well characterised. But what I'm looking for is the basic controllable laboratory experiment that measures the absorption of infrared radiation by varying concentrations of CO2 gas. I would love to see a graph showing changes in degree of absorption with changes of concentration.

 

On 1/28/2022 at 8:20 AM, Doogles31731 said:

There seems to be an assumption that it is linear, but there is another school of thought suggesting that the degree of absorption decreases with increasing concentrations of CO2. I would like to see the man basic work on which current models are based, but to date I haven't succeeded. 

The mathematical model is  this one.
https://en.wikipedia.org/wiki/Beer–Lambert_law
 

 

The complications due to the spectrum varying (slightly) with pressure and temperature are also well understood.

[Doogles31731]

The OP of this thread contained a reference to a 1960s paper by Manabe who subsequently received a Nobel Prize. One of the points made in the OP on Manabe’s work was “To test the model, Manabe decided to change levels of various greenhouse gases, such as carbon dioxide, to see what impact this had on the Earth’s temperature.” My question to Skydelph was if he knew what basic data on CO2 and temperature was used by Manabe to create his models. And then I extended that invitation to anyone in  the forum.

I could be wrong, but I believe that there has to be some basic quantitative data on the effects of increasing CO2 concentrations, for models and calculations to be meaningful.

The OP gave me the opportunity to see if any of the forum scientists knew of any such work since Tyndall’s crude experiments.

.............................................

I have good company in my queries about basic experiments. This site contains an open letter to the NASA Administrator from 49 members of the team producing much of the data used by the IPCC. All of the signatories are listed under the letter shown on this site. It’s a formidable-looking list - http://wattsupwiththat.com/2012/04/10/hansen-and-schmidt-of-nasa-giss-under-fire-engineers-scientists-astronauts-ask-nasa-administration-to-look-at-emprical-evidence-rather-than-climate-models/

March 28, 2012

The Honorable Charles Bolden, Jr.
NASA Administrator
NASA Headquarters
Washington, D.C. 20546-0001

Dear Charlie,

We, the undersigned, respectfully request that NASA and the Goddard Institute for Space Studies (GISS) refrain from including unproven remarks in public releases and websites. We believe the claims by NASA and GISS, that man-made carbon dioxide is having a catastrophic impact on global climate change are not substantiated, especially when considering thousands of years of empirical data. With hundreds of well-known climate scientists and tens of thousands of other scientists publicly declaring their disbelief in the catastrophic forecasts, coming particularly from the GISS leadership, it is clear that the science is NOT settled.

The unbridled advocacy of CO2 being the major cause of climate change is unbecoming of NASA’s history of making an objective assessment of all available scientific data prior to making decisions or public statements.

As former NASA employees, we feel that NASA’s advocacy of an extreme position, prior to a thorough study of the possible overwhelming impact of natural climate drivers is inappropriate. We request that NASA refrain from including unproven and unsupported remarks in its future releases and websites on this subject. At risk is damage to the exemplary reputation of NASA, NASA’s current or former scientists and employees, and even the reputation of science itself.

For additional information regarding the science behind our concern, we recommend that you contact Harrison Schmitt or Walter Cunningham, or others they can recommend to you.

Thank you for considering this request.

Sincerely,

(Attached signatures)

CC: Mr. John Grunsfeld, Associate Administrator for Science

CC: Ass Mr. Chris Scolese, Director, Goddard Space Flight Center

Ref: Letter to NASA Administrator Charles Bolden, dated 3-26-12, regarding a request for NASA to refrain from making unsubstantiated claims that human produced CO2 is having a catastrophic impact on climate change.

You can see the list of signatories on the site above.

..........................................................

Now my posts in this thread were simply to satisfy my own curiosity about the lack of repetition of Tyndall’s work with modern equipment under laboratory conditions where the variables can be controlled -- and nothing more than that. As I said in my last post I still have a couple of very old refs that I might check.

Can I ask if any members of this forum are happy with the basic science of a discipline that produces a 25-fold difference in estimates of ‘climate sensitivity’ in the first two decades of the 21st century. And that’s after 140 years of work in the area. I have not received a single comment on that fact.

I’m on the side of the NASA scientists. I would like to see more nuts and bolts-basic, controlled, quantitative laboratory experiments.

....................................................

John Cuthber, I notice that the Wikipedia article gives a list of 6 conditions under which the Beer-Lambert Law does not apply. The atmosphere, as a heterogeneous mixture of variables, some of which (such as CO2 and water vapour) are synergistic and not independent, seems to be one of them, yet the next paragraph gives a formula for calculating attenuation of solar or stellar light by the atmosphere. As I said, it’s largely beyond my comprehension. Are there basic experiments on which the Law is based?

John, could you explain how this Law could give an acceptable figure for ‘climate sensitivity’ and would such a finding be consistent under a variety of atmospheric variables?

Apologies, I meant to include an opening paragraph to directly answer exchemist's question -- 

Apparently I don’t express my thoughts very well. exchemist. You asked “What further experimental work were you expecting to find, or do you consider there should be? Because It is not obvious to me that any more experiments would be needed, as the challenge is in the modelling, rather than in the well known properties of the gases involved.”

I suppose the short answer is that the quantitative properties of the gases are not well known, in my opinion, because they have not been studied under controlled laboratory conditions. I don’t believe any calculations or modelling are good enough unless they are based on good quantitative basic data. I gave the example of variations in ‘climate sensitivity’ as a case of gross  inconsistency in modelling and calculations.

I’ll try rephrasing (above)

[exchemist]

4 hours ago, Doogles31731 said:

The OP of this thread contained a reference to a 1960s paper by Manabe who subsequently received a Nobel Prize. One of the points made in the OP on Manabe’s work was “To test the model, Manabe decided to change levels of various greenhouse gases, such as carbon dioxide, to see what impact this had on the Earth’s temperature.” My question to Skydelph was if he knew what basic data on CO2 and temperature was used by Manabe to create his models. And then I extended that invitation to anyone in  the forum.

I could be wrong, but I believe that there has to be some basic quantitative data on the effects of increasing CO2 concentrations, for models and calculations to be meaningful.

The OP gave me the opportunity to see if any of the forum scientists knew of any such work since Tyndall’s crude experiments.

.............[snip]......................

 

John Cuthber, I notice that the Wikipedia article gives a list of 6 conditions under which the Beer-Lambert Law does not apply. The atmosphere, as a heterogeneous mixture of variables, some of which (such as CO2 and water vapour) are synergistic and not independent, seems to be one of them, yet the next paragraph gives a formula for calculating attenuation of solar or stellar light by the atmosphere. As I said, it’s largely beyond my comprehension. Are there basic experiments on which the Law is based?

John, could you explain how this Law could give an acceptable figure for ‘climate sensitivity’ and would such a finding be consistent under a variety of atmospheric variables?

Apologies, I meant to include an opening paragraph to directly answer exchemist's question -- 

Apparently I don’t express my thoughts very well. exchemist. You asked “What further experimental work were you expecting to find, or do you consider there should be? Because It is not obvious to me that any more experiments would be needed, as the challenge is in the modelling, rather than in the well known properties of the gases involved.”

I suppose the short answer is that the quantitative properties of the gases are not well known, in my opinion, because they have not been studied under controlled laboratory conditions. I don’t believe any calculations or modelling are good enough unless they are based on good quantitative basic data. I gave the example of variations in ‘climate sensitivity’ as a case of gross  inconsistency in modelling and calculations.

I’ll try rephrasing (above)

OK, it looks as if we need to rewind a bit to explain some IR spectroscopy. The Beer-Lambert law is basic to spectroscopy and simply gives you a linear relationship, relating the % of radiation absorbed to the concentration of the absorbing species and the path length traversed by the radiation, i.e. the number of molecules in the path to do the absorbing. It is widely observed to be followed and is thus the basis of IR spectroscopy, which for decades has been a standard analytical technique in chemistry. 

You keep referring to Tyndall and suggest that nobody has followed up his experiment. That's because what he did was measure the absorption of "heat" (i.e. IR radiation) by various concentrations of gases, over a known path length. In other words, he had built a very primitive form of ancestor to the IR spectrometer. It was primitive in one particular respect, as it did not evaluate the absorption of radiation as a function of wavelength.

Since the advent of quantum theory in the 1920s and 30s, it has been recognised that IR absorption is due to vibrations of molecules and that the absorption depends on wavelength, since molecules absorb at particular ranges of frequency, related to the frequency at which they vibrate, which is characteristic of each chemical species. The technology of infra-red spectrometry was developed in the 1940s and 50s. Since then a huge range of materials has had their IR spectra characterised. I mentioned in an earlier post the "molar attenuation coefficient": https://en.wikipedia.org/wiki/Molar_attenuation_coefficient. This tells you how strongly a chemical species absorbs, as a function of wavelength, for a given amount of substance. The "given amount of substance" is determined by....................... our old friends the concentration and the path length of the radiation, a la Tyndall.

To work out the total absorption of IR radiation by a gas, you need to know the spectrum of the radiating object (since all objects radiate to different degrees at different wavelengths), and the IR absorption spectrum of the gas. You then integrate these over a range of wavelength or frequency, and that tells you the total absorption. 

So, given that we have known, for decades, both the spectrum of the sun and the spectrum of CO2, in exquisite detail, it is quite pointless for anyone to waste time putting more gas into tubes in the way Tyndall did back in 1859.

As for synergy between CO2 and water, there is no synergy between their IR absorption profiles. Each species absorbs according to the vibrational characteristics of its molecules. If two species are present, you sum their effects. You do this in the modelling, not by filling tubes with mixtures of gases, which is quite unnecessary.

 

 

Edited February 1, 2022 by exchemist

[exchemist]

Out of interest, here is a link to  Tyndall's paper: https://geosci.uchicago.edu/~archer/warming_papers/archer_galleys/9781405196178_4_002a.pdf

Seems he used various sources of heat (copper plate heated by a gas flame, hot metal cubes) as radiation sources, rock salt plates to close the tube containing the gases and a galvanometer to measure the voltage change due to the effect of absorption on a "thermo-electric pile" (thermocouples connected in series) that he used as the detector. He looked at a range of gases and vapours and noted that the amount they absorbed varied widely.  Interesting to see how much of the paper is devoted to the experimental setup, which was evidently far from straight forward. Very ingenious indeed, given the state of knowledge of the time.   

[studiot]

The use of the Beer-Lambert law is still modelling, albeit simpler than the billion tax dollar computer models currently promoted.

7 hours ago, Doogles31731 said:

The OP gave me the opportunity to see if any of the forum scientists knew of any such work since Tyndall’s crude experiments.

 

 

On 1/31/2022 at 6:28 AM, Doogles31731 said:

Following my search so far, my expectation now is that I’ll find that the only basic laboratory-controlled experiment in the field was that of Tyndall’s in the 1860s.  He used a can of hot water, a tube and a galvanometer to quantitatively assess the absorption (and radiation) of ‘heat’ by a variety of gases. It doesn’t look at this stage as if anybody has repeated his work using infrared lamps and spectrophotometers with a glass or perspex tube designed to hold a variety of pure or mixed gases at various temperatures and simulated atmospheric conditions, along with inserted thermometers and gas gauges. The design and manufacture of such a tube would probably be the biggest technical problem in a machine designed like an Atomic Absorption Spectrophotometer.

I don't see how this would not still result in a model.

Surely from a climate science point of view, only actual measurements on the actual atmousphere count ?

Here are a couple of graphs of slightly older data, including references that might provide a starting point for you.

Edited February 1, 2022 by studiot

[swansont]

On 1/26/2022 at 4:04 PM, Doogles31731 said:

I've personally searched the literature for early BASIC studies on the measurable absorption and radiation properties of infrared radiation by carbon dioxide gas and so far, have only found the work by Tyndall in the 1860s.

Googling “carbon dioxide absorption spectrum” only yields about 19 million results

On 1/29/2022 at 6:38 PM, Doogles31731 said:

If the basic science is so good, why do we have so many variations in predictions of ‘climate sensitivity’ by climate scientists? As you can see from the graph, the estimates have varied maybe 25-fold since 2000.

The graph shows no such thing. The scale on the graph only covers a factor of 6, and the data doesn’t even span that scale.

[exchemist]

45 minutes ago, swansont said:

Googling “carbon dioxide absorption spectrum” only yields about 19 million results

The graph shows no such thing. The scale on the graph only covers a factor of 6, and the data doesn’t even span that scale.

Yes, it's curious that @Doogles31731 seems to have chosen to base his climate change scepticism on claiming the absence of something that has been in every gas chemist's handbook for the last 50 years or so. I had felt at first there must be some more subtle point behind his enquiry, but it seems not. 

And now we get a separate issue being introduced, viz. this 10 year old letter from a group of retired NASA engineers (+ one meteorologist), asserting that the climate change issue should not be presented by NASA as settled science. Well, they would know - not. And 10 years ago is quite a while in climate science. 

I'm no longer sure what our poster is trying to achieve here. He talks of belief systems. Maybe he is onto something, but not in the way he means it. 

   

Edited February 1, 2022 by exchemist