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Author Topic: What does Iain Stewart's "CO2 experiment" Demonstrate  (Read 29636 times)

Offline Pete Ridley

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #50 on: 04/05/2011 19:42:14 »
It looks as though I’m going to have to go back to square one here, but tackle this question from another angle. Let’s first look at what Professor Stewart claimed that his demonstration (
)  would show, quoting those words of his that in my opinion will mislead any of the target audience who have no understanding of how the demonstration is set up or how much of the IR from a heat source such as a candle, the sun or even the earth CO2 absorbs.

0 to 19 secs –
Quote
I can show you how carbon dioxide affects earth’s climate using this heat sensitive infrared camera .. a candle, this glass tube .. this canister of carbon dioxide gas ..
but does it do anything of the sort? No, showing that a candle flame changes from white to blue when viewed through CO2 and a 4 µm filter using an IR camera shows nothing whatever about CO2’s effect on the earth’s climate.

22 to 28 SEC. - 
Quote
.. the camera picks up the flame perfectly. The hot spots are glowing white ..
but does it do that? No, the camera picks up only a very small part of the flame’s emissions.

30 to 108 secs. –
Quote
.. When I turn on the carbon dioxide .. the carbon dioxide in the tube is effectively trapping the heat. The candle’s warmth no longer reaches the camera. Instead it is absorbed by the carbon dioxide inside the tube ..
but is that correct? No, it is the filter that is trapping most of the candle’s heat, not the CO2, so that is why the most of the flame’s emissions don’t reach the camera.

The question raised by that demonstration is the one that Geezer couldn’t answer
Quote
.. what motivated Stewart to screen the demonstration ..
I’m interested in that question too and trust that it is acceptable to the thread moderator to try to answer it here. If there is no objection to this then I’ll do a follow-up comment using some interesting stuff I found.

Best regards, Pete Ridley
 

Offline Geezer

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #51 on: 04/05/2011 19:58:20 »
Pete,

No need to back to the beginning. Your question was "What does the experiment demonstrate?"

It clearly demonstrates that CO2 absorbs IR.

Whether or not Stewart intended to mislead his audience, or otherwise, would be a totally different question.
« Last Edit: 04/05/2011 20:01:30 by Geezer »
 

Online Bored chemist

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #52 on: 04/05/2011 20:28:44 »
Pete,
How would you demonstrate to a lay audience that CO2 absorbs IR?
 

Offline JP

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #53 on: 04/05/2011 20:35:46 »
The question raised by that demonstration is the one that Geezer couldn’t answer
Quote
.. what motivated Stewart to screen the demonstration ..
I’m interested in that question too and trust that it is acceptable to the thread moderator to try to answer it here.

No, it isn't acceptable to try to answer that here.  This thread is about what science the experiment demonstrated and whether or not that science was adequately explained by the presenter's comments.  I think we've pretty well covered that the science is absorption of IR by CO2.  We're divided on whether the verbal explanation of the experiment was accurate or not, and don't seem to be getting anywhere with it. 

I believe the one thing that remains contentious point is if if the presenter's claim that:
Quote
I can show you how carbon dioxide affects earth’s climate
is adequately explained by the experiment.
« Last Edit: 04/05/2011 20:44:30 by JP »
 

Offline Pete Ridley

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #54 on: 04/05/2011 21:09:13 »
Hi JP, thanks for the speedy response on that question of Geezer’s
Quote
.. what motivated Stewart to screen the demonstration ..
I hope that there will be no objection to me raising it as a separate but relate question, which should cover Geezer’s point in his comment today at 19:58:20.

Regarding your
Quote
I believe the one thing that remains contentious point is if if the presenter's claim that:
Quote
I can show you how carbon dioxide affects earth’s climate
is adequately explained by the experiment
do I take that to mean that you agree with my other two points:
Quote
No, the camera picks up only a very small part of the flame’s emissions
and
Quote
No, it is the filter that is trapping most of the candle’s heat, not the CO2, so that is why the most of the flame’s emissions don’t reach the camera.
?

The question
Quote
Pete, How would you demonstrate to a lay audience that CO2 absorbs IR?
is also off-topic so if that and Geezer’s questions can only be raised as separate ones this gets very messy. After all, one question always leads to another related one. Never mind, forum moderators appear to set their own rules here so we visitors have to abide by them.

Is there a mechanism for linking questions other than verbose explanations about their relationship, or is that classed as off-topic and require that a separate question be submitted for that too?

Best regards, Pete Ridley
 

Offline Geezer

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #55 on: 04/05/2011 21:18:03 »
Pete,

I didn't raise any questions.
 

Offline Pete Ridley

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #56 on: 04/05/2011 21:59:45 »
Hi Geezer, sorry if I misunderstood your “I really don't know what motivated Stewart to screen the demonstration”. I took that as you raising (i.e. bringing up) the question. I don’t recall anyone else mentioning it but may have missed it.

Best regards, Pete Ridley
 

Online Bored chemist

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #57 on: 04/05/2011 22:11:10 »
Pete,
if you say "He did it badly" (and you have) then it's perfectly reasonable to ask how you would do it better.

If you want to go to an absolutely strict limit to what's on topic then the question has been answered (repeatedly); the clip shows that CO2 absorbs IR.
 

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Offline Pete Ridley

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #58 on: 04/05/2011 22:33:07 »
Shrunk
Bored chemist, with all due respect I can’t see how you can be so sure what is perfectly reasonable to ask. Let’s leave it to the thread moderator to declare his ruling, shall we.

Best regards, Pete Ridley
 

Offline peppercorn

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #59 on: 04/05/2011 22:45:44 »
Pete, BC's point stands and, as such, deserves a valid response.
I would comment that you have derailed the very valid scientific responses you have been offered for long enough and it is getting likely that you will find yourself soon 'out of rope' in the very near future; if you get my drift.
 

Offline Pete Ridley

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #60 on: 05/05/2011 08:07:21 »
Hi Bored chemist, ref. your comment yesterday @ 20:28:44, if you read my comment here of 23rd April @ 20:36:04 you will find an answer in the third paragraph (E-mailed to Professor Stewart and Dr. Hare on 18th April). If the moderator confirms that I am permitted to follow up on that point here then I shall do so but not before.

You may recall your comment here on 21st April @  19:03:23
Quote
.. TV science isn't real science- its dummed down for an audience who are not experts in the field ..
As far as climate science is concerned (which is what we are talking about here) I would say that “hyped up” is more appropriate that “dumbed down”.

 Hi Peppercorn,  do you recall your comment on 15th April @ 17:32:52
Quote
Why do you think you should 'bring it over'? Unless it's a completely separate question (which it appears not to be) it should stay in the original thread.  Reiterating is not likely to get an answer any quicker & flies in the face of the site's AUP. I think you can expect to find the two merged quite quickly unless you can justify your need to start a new thread on the same subject
If I had not opened this thread at that time these hot topic” exchanges would almost certainly not be taking place due to action by moderator yor_on.

I also tried to start discussing the manner in which climate science is presented through the media to the general public by prominent scientists and the impact that this was having on the credibility of scientists generally. I focussed initially on The Naked Scientists and for my pains was told by moderator JP on 22nd April @ 14:25:10
Quote
.. in this thread please stick to the question at hand, which is about the youtube video you posted.  I will lock this thread if you keep using it to .. editorialize about other topics..

I'm doing my best to stick to the "rules of engagement".

Best regards, Pete Ridley
« Last Edit: 05/05/2011 08:09:01 by Pete Ridley »
 

Offline JP

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #61 on: 05/05/2011 13:16:21 »
All right.  This seems to have been derailed pretty thoroughly, so I'm locking it.
 

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What does Iain Stewart's "CO2 experiment" Demonstrate
« Reply #61 on: 05/05/2011 13:16:21 »

 

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