[alancalverd]

The actual spectrum can be found here- it's a JCAMP file which isn't that commonly used.
http://webbook.nist.gov/cgi/cbook.cgi?ID=C124389&Type=IR-SPEC&Index=1#IR-SPEC

Many thanks for that! I've seen the graph before but not the key facts of partial pressure and path length. Up to my ears in business today but I'll work on the  numbers ASAP.

I've never doubted your qualifications or integrity, which is why I suggested you might have had a bad night.

A model of heat transfer in the atmosphere? It's inherently chaotic, for the reasons I gave earlier, and I have no intention of attempting to model it - there are more profitable walls to bang one's head on. The only answerable question is, given no other changes, what would be the effect of increasing CO2 concentration if the atmosphere was dry and momentarily stable?

[puppypower]

I must be missing something.
You want the spectra of pure CO2 at 1 atm pressure measured with 2 metre and 4 metre path lengths?
Same temperature, same pressure, no other gas present?

You don't understand why nobody has done this and published the results?

What interests me is a measurement of the effect of doubling the concentration of carbon dioxide in the atmosphere, with no confounding effect from water. The spectral detail doesn't matter greatly: what matters is the change in total transmittance over the infrared region.

It seems that there are two ways of approximating this, either to measure the effect of doubling the path length through pure carbon doxide at atmospheric pressure (given that 300 ppm  distributed through the entire atmosphere is roughly equivalent to 2 m of pure gas at 1000 mb pressure) or to simply double the concentration in a reasonable sample of dry ambient air and extrapolate the Beer-Lambert equation to 50 km path length. That would be a more realistic approximation as it takes into account the true pressure broadening due to nitrogen, oxygen and argon rather than just carbon dioxide, but it needs to be at least 50,000 times more accurate so might not be feasible.   

Now the first experiment is obviously feasible with kit you can find in a decent undergraduate laboratory, and the second may need a bit of instrumentation development. Alas, I don't have the facilities or the time at hand right now to do either, but it's the kind of project that could entertain a bored chemist!

Sorry, but I'm not that bored and I hope I never will be.
You probably don't realise it, but you are proposing an experiment to determine whether or not photons have a memory.
Since there's no plausible mechanism for that, and no evidence to suggest that it's true, there's no point doing the experiment.

There is a difference between applied science and pure science. Photon memory may make no sense in terms of pure science, since this does not  reflect the natural reality of photons. However, in applied science this theory, although not natural, might still lead to an invention, which allows a tangible experimental result.

Let me give a real example that is already done. One will not find natural aluminum metal on the earth, since aluminum will oxide, to form aluminum oxide. But say it was 100 years ago and I believed metallic aluminum was natural. I could go to the lab and use electricity to make metallic aluminum. I can then try to find a possible natural mechanism for electricity; reverse engineer metallic aluminum in nature. Just because I can make metallic aluminum in the lab, does not mean it is natural. Unnatural things can be done in the lab. Applied science; creative science, can be the basis for magic tricks, to fool people to believe artificial is natural. 

As a light hearted example, say I needed to convince the king I could conjure the spirits of the dead from a fire. This is not natural science but hogwash. However, if I knew enough chemistry, I could use applied science to make this appear to work. I could find mineral salts that will make various colors, in the fire. I will then speak to the dead, and they will respond to me through the colors of fire, which I will then interpret for the king. 

It can sort of look natural to the untrained eye; higher human potential, since people can the color flames in action, which seem to follow my questions. Part of this is psychology to build you sensory expectation; see what you want to see. But still the illusion can be perform using applied science. If other magicians know my trick, they can repeat my results.

Magic was among the first science. It used both natural science and applied science to trick people, about that nature of natural science. Levitation is possible in magic even of not natural. Those who believe what they appear to see will think this is natural. Most inventions have little basis in nature, yet they exist as part of reality. Natural is an arbitrary line in the sand, since if human creates it, and humans are apart of nature, it becomes part of reality.


To me, I sense that manmade climate change is a magic trick that uses applied science to define alternate natural science. It is a good trick and fools most people. It can conjure doom and gloom using computer oracles. This is fancier than mineral salts and fire.


I used to be an applied scientist. I remember being given a project, where I was asked to use bacteria to treat waste acid ponds. Based on natural science, the parameter of the pond experiment, far exceeded what was assumed possible with those bacteria; natural science.  But since I was an applied scientist, I had a job to do, which did not limit me to only natural paths. I got it to work. It was applied science, that looked like magic, to the experts who focus on the natural. It turned out I was a bacteria whisperer using applied concepts.


My gut tells me manmade global warming is an applied science affect being sold as natural. If that had been my assignment I could have come up with other applied applied tricks.  But nobody asked me.

[Bored chemist]

The actual spectrum can be found here- it's a JCAMP file which isn't that commonly used.
http://webbook.nist.gov/cgi/cbook.cgi?ID=C124389&Type=IR-SPEC&Index=1#IR-SPEC

Many thanks for that! I've seen the graph before but not the key facts of partial pressure and path length. Up to my ears in business today but I'll work on the  numbers ASAP.

I've never doubted your qualifications or integrity, which is why I suggested you might have had a bad night.

A model of heat transfer in the atmosphere? It's inherently chaotic, for the reasons I gave earlier, and I have no intention of attempting to model it - there are more profitable walls to bang one's head on. The only answerable question is, given no other changes, what would be the effect of increasing CO2 concentration if the atmosphere was dry and momentarily stable?

OK, but saying I must have had a bad night when I was perfectly correct is still doubting my ability.
 
"The only answerable question is, given no other changes, what would be the effect of increasing CO2 concentration if the atmosphere was dry and momentarily stable? "
Who cares?
It has sod all to do with the topic.

[Bored chemist]

My gut tells me manmade global warming is an applied science affect being sold as natural. If that had been my assignment I could have come up with other applied applied tricks.  But nobody asked me.

Reality doesn't know or care what your gut thinks.
If you want to find out what the world does, may I suggest that you try using your brain instead?

[zx16]

A close friend of mine has suggested that this whole "Global Warming" debate is a deliberate attempt to divert public attention from mass third-world immigration into western countries.

Is this credible, do you think?

[Bored chemist]

A close friend of mine has suggested that this whole "Global Warming" debate is a deliberate attempt to divert public attention from mass third-world immigration into western countries.

Is this credible, do you think?

No.
It's not remotely credible.
There's no mass immigration, and global warming is real.
So the idea is wrong on both fronts.

[zx16]

Thanks Bored chemist.

[alancalverd]

"The only answerable question is, given no other changes, what would be the effect of increasing CO2 concentration if the atmosphere was dry and momentarily stable? "
Who cares?
It has sod all to do with the topic.

If increasing the CO2 concentration would have a significant effect on atmospheric temperature, then there is a link and the skeptics, in terms of the topic, would be wrong. I think a direct yes/no answer is always relevant to a simple question.

I've had a lousy day with more grief to come tomorrow, so I'll put off the promised calculations for a while, but I will be back!

[alancalverd]

As an aside, I have just come across this experimental investigation http://personal.inet.fi/surf/atn/vdco2/wdindex.html. Crude, but gets full marks for ingenuity, enthusiasm, and a serious attempt at analysis. 

[puppypower]

"The only answerable question is, given no other changes, what would be the effect of increasing CO2 concentration if the atmosphere was dry and momentarily stable? "
Who cares?
It has sod all to do with the topic.

If increasing the CO2 concentration would have a significant effect on atmospheric temperature, then there is a link and the skeptics, in terms of the topic, would be wrong. I think a direct yes/no answer is always relevant to a simple question.

I've had a lousy day with more grief to come tomorrow, so I'll put off the promised calculations for a while, but I will be back!

I showed this plot before, as shown below. What it shows is global temperature versus CO2 concentration over the last 600 million years. The graph shows both positive and negative correlations of temperature to CO2. Looks at 150 million years ago to the present. The temperature rose as the CO2 was falling. This is longer than just 100 years used to justify the current correlation. What this tells me is the impact of CO2 is not as simple as it is being sold. It tells us other factors can override CO2.





What is being accepted comes back to the point I made between pure and applied science. Pure science developed this graph, which shows both positive and negative correlations based on a plot of CO2 and temperature. The current claim, of manmade, has never happened before in the history of the earth. The data field covers only100 years, instead of 100, 000,000 years of data where it was not valid. Maybe someone can find us a plot of manmade climate change over the past 500 million years, which can include alien civilizations. We are told this narrow range of data, that represents a unique event, and that this trumps 600 Millions years of pure science data.


Let me give you another example of how confusion that can be created, if one cannot make a distinction between pure and applied science, and someone wanted to take advantage of this. Diamonds, which are a girl's best friend, are assumed, by pure science to take millions of years to form under conditions of high temperature and pressure.


Based on applied science, you can make gem quality diamonds; girls best friends, in the lab in months. Conceptually, using a modification of these applied science techniques; hot pressure and catalysts, one could propose a faster track natural mechanism, near volcanoes, for making natural diamonds. I can say it will take one thousand years. This will be a unique data point, that will be a work in progress to simulate the manmade claim.


The natural scientists would scoff at this proposal, since everyone knows diamonds take millions of years. They would say this is a trick. But if I make such diamond, would that change anything? The answer will depend. The slow train theory would still get the two thumbs up, because the  slow formation theory makes diamonds worth more in the free market. A fast track theory will lower the value. It is not always about logic and common sense, if applied or pure is worth more in the market place.


Global warming was the biggest financial boost the climate industry has ever had. They will not give this up for a better theory that pays less and needs less experts due to more resolved conclusions. However, it may be the opposite in the next budget, where less spending will mean more, and pure science will win by default.

[Bored chemist]

"The only answerable question is, given no other changes, what would be the effect of increasing CO2 concentration if the atmosphere was dry and momentarily stable? "
Who cares?
It has sod all to do with the topic.

If increasing the CO2 concentration would have a significant effect on atmospheric temperature, then there is a link and the skeptics, in terms of the topic, would be wrong. I think a direct yes/no answer is always relevant to a simple question.

Well, if a simple yes or no is helpful then the answer is no. They are wrong. There is a clear link.
That fact is implicit in your suggestion that we might do an experiment or simulation to find out  at what level the effect saturates.

However, your suggested simulation will- at best- answer the question for a world that is totally different from the one on which we live.
Why is that useful?

Also, have you accepted that your original suggested experiment was pointless and that your reply to my observation was just plain rude, or are you still trying to pretend that this
"What utter drivel - unworthy of you, BC.
Do they really hand out chemistry degrees at Trump University?"
was, in some way justified?

[alancalverd]

Because the suggestion that I was implying photon memory was unworthy of you.

Anyway the question is misleading. There is obviously a link. But the link is not obvious, and that's why model-based predictions have fallen short of any useful accuracy.

[Bored chemist]

Because the suggestion that I was implying photon memory was unworthy of you.

Anyway the question is misleading. There is obviously a link. But the link is not obvious, and that's why model-based predictions have fallen short of any useful accuracy.

As I said; you were implying that photons had a memory- you just didn't understand what you were talking about and thus were unaware of this implication.
The only way your proposed experiment would have provided any new information would have been if photons remembered to behave differently passing through a second column of CO2 after being through a first one.
Why is it unworthy of me to point it out?


I think this sums up your position nicely
"There is obviously a link. But the link is not obvious"

[alancalverd]

Obviously (to a physicist) any photon that had interacted with a CO2 molecule in the first pass, would not be present in the second pass. That's quantum mechanics. The experimental measurement is to determine is how many photons survive the first pass and are absorbed in the second, because that it the determinant of additional heating due to doubling the CO2 concentration of the atmosphere. Nothing to do with memory.

For the benefit of onlookers (if we have any) my cryptically concise concern is that whilst there is a clear correlation between CO2 and temperature, the phase lags and annual anomalies are not consistent with CO2 being causative, and one is always suspicious of models that (a) are based on "adjusted" data, (b) have not proved usefully predictive and (c) ignore the elephant in the room (water).

[Bored chemist]

Obviously (to a physicist) any photon that had interacted with a CO2 molecule in the first pass, would not be present in the second pass. That's quantum mechanics. The experimental measurement is to determine is how many photons survive the first pass and are absorbed in the second, because that it the determinant of additional heating due to doubling the CO2 concentration of the atmosphere. Nothing to do with memory.

"The experimental measurement is to determine is how many photons survive the first pass and are absorbed in the second, "
And the experiment is pointless because we know that the answer is "exactly the same fraction that made it through the first".
If you plot the spectra as photon collision cross sections (which a physicist might well do) the spectra for the 2 and 4 metre paths are exactly identical.
If you plot them in absorption units one is simply twice the other and if you plot them in percent  absorption the 4 metre result is the square of the 2 meter experiment.
You do not gain any further information.
(unless, of course, you show that photons have memory)



Asserting  that the probability of  a photon making it through the second pass depends on whether it had previously made it through the first pass require the photon to have memory.

Since you say repeatedly that you needed to check the spectra for both a single, and a double pass, it seems that you believed the transition probability was not the same in both cases.
So you were asserting that a photon has memory. though I accept that you didn't understand that you were doing it.

Another way to look at the same question: If you don't think a photon has a memory, why did you think anyone would bother to do the experiment you proposed?

What did you imagine that anyone would learn from it?

[alancalverd]

Asserting  that the probability of  a photon making it through the second pass depends on whether it had previously made it through the first pass require the photon to have memory.

Quite. Which is why I haven't asserted it.

Until I read the small print in the reference you so kindly provided, I hadn't seen any usefully accurate data on the absorption spectrum of CO2 under realistic atmospheric conditions. There's a lot of handwaving on the internet about pressure broadening and metastable hydrates, but a surprising dearth of numbers. Now we (or at least I) seem to be getting somewhere but I'd still prefer to see "real world" experimental data rather than extrapolate from a somewhat idealised atmosphere.

[Bored chemist]

Asserting  that the probability of  a photon making it through the second pass depends on whether it had previously made it through the first pass require the photon to have memory.

Quite. Which is why I haven't asserted it.

Until I read the small print in the reference you so kindly provided, I hadn't seen any usefully accurate data on the absorption spectrum of CO2 under realistic atmospheric conditions. There's a lot of handwaving on the internet about pressure broadening and metastable hydrates, but a surprising dearth of numbers. Now we (or at least I) seem to be getting somewhere but I'd still prefer to see "real world" experimental data rather than extrapolate from a somewhat idealised atmosphere.

And again...
Yes, you have- you just don't understand that you have  done so.

As I said- and you failed to answer.
"If you don't think a photon has a memory, why did you think anyone would bother to do the experiment you proposed?"

[zx16]

I think, that so many scientists have committed themselves to the idea that global warming is caused by humans, that they can never retreat, without a disastrous loss of face.

[Bored chemist]

I think, that so many scientists have committed themselves to the idea that global warming is caused by humans, that they can never retreat, without a disastrous loss of face.

You can't understand science if you think that.
What would be a disaster for a scientist would be if they wre shown the evidence that they were wrong, but chose not to accept it.
There's nothing wrong in science with saying "I was mistaken".
You seem to have muddled it with politics.

[Tim the Plumber]

I think, that so many scientists have committed themselves to the idea that global warming is caused by humans, that they can never retreat, without a disastrous loss of face.

I think you will find that the scientists you speak of are very careful to phrase their wording so that they can point to it and show that it does not say that all or even most warming is definately attributable to human activity.

Large organisations on the other hand where the actual author is not singled out do all the time. Odd that.