The peer-reviewed literature is unanimous in finding that the residence-time of CO2 in the atmosphere is about 7 years. The UN’s climate panel, however, chooses a complex and unsatisfactory definition of residence-time that allows it to pretend that the residence time is in fact 100 years. This is one of many respects in which the climate panel, while claiming to represent the “consensus” of scientific opinion, is in fact entirely at odds with the peer-reviewed literature.
Crakar is confusing the residence time of an individual CO2 molecule with the residence time of an increased CO2 level. CO2 cycles in and out of the atmosphere constantly and in quantities much larger than we emit (a fact continually misrepresented by the denialist echo chamber) so an individual molecule will on average stay in the air a small number of years. I am writing this quickly and offline so am not verifying the quoted figure crakar offers, but the flaw in his understanding is clear regardless of the real value.
The critical property humanity must be concerned with is not how long or how many CO2 molecules actually made from fossil fuel combustion are in the air, but how long will levels driven higher by us stay higher. This figure is actually on the order of centuries.
I gratefully accept proper figures/calculations/citations in the comments.
An honest skeptic faced with this simple and clear distinction will acknowledge that this “science says 7, IPCC says 100” canard is false. What will crakar and snowman do? And I wonder how they reconcile a 7 year residence time with the quantity of extra CO2 now in the air, it is much more than 7 year’s worth.
Can you say “cognitive dissonance”?
A Few Things Illconsidered 
This, by the way, was an appallingly blatant diversion by Crakar (R.I.P.).
I actually thought at first blush he was on to something here but when I realized who he was citing and what they in fact proved I was actually kind of angry with him.
He didn’t enough respect for us or himself to avoid such a lame red herring.
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Actually, I’m quite sure he doesn’t understand, so don’t judge him too harshly on this point.
Judge him harshly on his inability to understand, thus his ideologically driven anti-science postings.
Which makes one wonder … why did Crack and Snow have to self-ban themselves on a science blog?
If I – an atheist – posted crap continuously on some christian site, I’d totally lose respect for them if they didn’t say “hey, just go away”.
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Atheist, eh?
I’ve dabbled with atheism–dutifully read my Dawkins–but finally decided that even though it *looks* like we live in a Godless cosmos, that’s just it: it *looks* that way to *me*, and I would rather not leave such a momentous pronouncement to my own–or anyone else’s–intellect.
It goes back to *narratives*. (I know, I know, dhogaza; I am something of a one-trick pony.) Atheism is just another narrative interpretation of the universe by passionate, myopic bipeds on the third planet from an obscure star in the Milky Way.
Its also why I always give these AGW deniers a chance: Knowing how halting are my own powers of perception, and since I would rather *not* believe in AGW, I am willing to brook any argument against it–even a stupid argument like Crakar’s asinine “residence time” point, but never more than once.
Happy disbelieving,
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That’s all right: Crakar’s in good company: Professor Essenhigh actually got a paper published pushing this idea in a decent Chemical Engineering Journal (Energy & Fuels). On my to-do list is to right a proper rebuttal and send it to the journal…
-Marcus
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hi
Wonder if anyone could help me to debunk this argument from the denialists about the radiation absorption spectra of Co2. For some reason this argument really irritates me. They claim that CO2 is ‘saturated’ in terms of its absorption and the show the famous logarithmic graph of absorption vs concentration. Now I know this is rubbish for two reasons. Firstly, CO2 at high altitude (therefore low pressure) has far more defined spectra and does not compete with water vapour and is therefore NOT saturated. Secondly even at sea level newer spectrographic studies have shown that the CO2 spectra are not saturated at all. When I say this, the deniers say that there are competing theories about the spectra and the science isn’t settled. I can’t find any evidence of this on the web? Is it true? What is the state of understanding with regards the spectra?
Of course I am well aware that all this might be is a slight disagreement over some minute issue which the denialists are trying to turn into some major problem which overthrows the whole theory? Is this what they are doing?
PS: going to a Bob Carter (australia) lie-fest tomorrow night and would like to try and get this sorted out in my own mind.
Thanks
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@greg:
http://www.skepticalscience.com/saturated-co2-effect.htm
http://rabett.blogspot.com/2007/07/temperature-anonymice-gave-eli-new.html
are good starting points
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going to a Bob Carter (australia) lie-fest tomorrow night and would like to try and get this sorted out in my own mind.
The insomnia struck and I noticed this.
Out of curiosity, Greg: Is this a public speech by Carter? Is it open forum?
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Along with the technical links given above, you might relate some history. Ask your denialists if they’re aware that angstrom made this claim at the end of the 19th century and it took all the way until the 1950s for physicists to show why this argument is bogus. Took them fifty years. Of course, that also means they showed it was bogus fifty years ago. Ask your denialists why they think a 100 year old argument disproved 50 years ago is correct.
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skip: Our local climate denialist activist here in Kalgoorlie, WA has organised the event. Apparently he has some mining companies as sponsors and he also bullied the local chapter of the Australian Institute of Mining and Minerals to co-hosting. It’s a public speech but I’m not sure how they’ll handle questions. A few months ago Plimer came to town, organised by the same nutjob and I brought up the same CO2 saturation issue. He actually said that “in theory” i was right regarding the spectra but that the science wasn’t settled blah blah blah. But I only got one chance to talk and they wouldn’t let me follow up on Plimer’s response.
dhogaza: I’ve checked Carter’s preso’s on the net and of course he brings up this argument. I think that might be a good idea to bring up the history aspect and say that what he has presented was the state of the science 60 years ago and get him to explain why he doesn’t include all the other stuff like the fact that less radiation is being detected from space proving that the CO2 is not saturated.
Thanks for the links, guys. But does anyone know what these creeps are talking about when they say the radiation science isn’t settled? Is there some argument amongst physicists or climate scientists that they are blowing out of proportion? I just want to be forearmed if he does try and say that.
Cheers
Greg
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As far as I know, as a layman fairly well cognizant of climate issues, there is no argument whatsoever among legitimate researchers.
Remember, though, that the flat earth society is alive and well, too! 🙂
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Greg, I wonder if a different tactic would be better, most layman/woman don’t understand technical discussions, especially something like CO2 saturation.
What if you took a leaf out of the denier handbook, seed the audience, this time with knowledgeable sane people – assuming there’s a question/answer session. Pretend to be sincere and ask questions like:
“Mr Carter what’s your theory for the recent warming?”
“if the science isn’t settled, what research are you undertaking Mr Carter, to help clarify the issue?”
“Why is the stratosphere cooling, but the Troposphere isn’t?.”
“What is the explanation for Earth Radiation Budget imbalance?, what’s happening to the missing outward energy?”
“if it’s the sun, I’ve heard the suns radiation output was much lower in prehistoric times, do you know how much lower, say during the Permian Period?”
“Seeing as Cosmic Rays don’t explain the recent warming, is there another hypothesis other than CO2 that explains the scientific observations?”.
Make the idiot deniers do the work, offer up a leading question, or insinuation that they have to work hard to try and counter.
Just a suggestion .
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Dappledwater: When Plimer was in town I tried the CO2 saturation argument and Plimer knew exactly what I was talking about, but no one else did! So you’re right. It’s just that deniers hide behind the complexity off the argument and thereby totally misrepresent the core mechanism of AGW. It drives me mad. Anyway, I think you might be right to rather approach it the way you suggest. Another idea I had was to ask what evidence he would require to accept that AGW was happening. In other words, to see if he actually accepts that his hypothesis is falsifiable. Do you think that would work, or would a slippery denier talk their way out of that one?
Cheers
Greg
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I agree with the tactic being advocated by Dappledwater. The deniers generally occupy themselves by repeating tired arguments, but often those arguments are contradictory to each other. Force them to try to come up with some sort of coherent and consistent hypothesis of their own – one that explains the variety of observations nearly as well as actual climate theory. Then ask for a quantitative model that’s anywhere near as skillful as the current ones.
To disprove saturation arguments, you have to discuss radiation transfer and spectral lines on a level beyond the physics understanding of most people. Which is a shame, because the saturation argument is fairly intuitive, even if you’ve never heard of Beer’s Law. It’s annoying when you can’t give an easily understandable answer.
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Thanks for the advice, all. I am going to let the saturation thing go. I’ll try some of your suggested strategies. I’ll report back tomorrow 🙂
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Feedback on Bob Carter talk: all the usual denialist rubbish. Nothing at all new. But I must say very clever to avoid topics where he could be shot down. Almost no mention of the greenhouse effect. So I hammered on that in the questions and got him to agree that increasing CO2 levels will push tempereatures up “but only by 1 degree”. So I said but the climate models that include feedbacks say it will be 3-6 degrees. He said they only include the positive feedback loops and they don’t include feedbacks they don’t know about. So I said firstly it’s ridiculous to expect them to include feedbacks they don’t know about and they DO include “negative feedbacks”. Got into a bit of “yes they do, no they don’t, yes they do, no they don’t.” Haha, was quite funny.
Then I said “just to clarify, you agree that by adding CO2 we will increase temperature but you disagree by how much”. He replied yes, so then I said “well most scientists say that it is 3-6 deg increase”. Oh they’re wrong. Then he changed the subject. btw, the audience was quite small 25 or so and were all already pretty much converted, so I don’t think much damage was done anyhow.
I also pinged him on what he thinks is causing climate change. He said it’s all natural, the sun, orbital effects. He offered no evidence for this but I couldn’t quiz further. Also got him on the argument about CO2 increasing plant yields. Said that the “fertilizing” effect of CO2 will be swamped by the huge increase in temperature and drought and that yields will fall 40%. Of course he disagreed with that.
Overall I got a few good jabs in amongst a very supportive audience and interestingly there was one farmer who had been flying this noodle Carter around the state to various towns to deliver his talk. He came straight to me afterwards and wanted to hear “my side of the story”. So we had a very interesting chat. He seemed open to listening to the “other side”. During the chat, Carter came and stood by us and was listening. I said to the farmer dude “you noticed that Bob said very little about the greenhouse effecct and then when I pushed him on it he agreed on it?” I said that Bob says the only thing that he disagrees with is the size of the change, why the effect, why then did he not spend the entire preso explaining that to us? Carter just stood there. Very interesting. So I think I might have got at least one person to “think” a little bit.
Anyhow, I know it’s like pushing shit uphill with this kind of thing. But I definitely took the wind out of his sails a bit. About half the talk was political ranting about those darned greenies and he is sponsored by the Institute of Public Affairs which is a well known denialist supporter and conservative “think tank”. So we know that he’s more interested in the politics and he’s just co-opting the science to make his point. What a loser.
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*applauds greg*
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Well done Greg.
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Greg, yes, that’s great. One point, though, just in case you find yourself discussing this with a farmer again … if scientists are right, and denialists wrong, it is farmers who will be among those hurting the most. Take it home. Make it personal…
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Very nicely done, Greg. I think you’ll find that anybody with an iota of reason will allow that doubling CO2 will result in at least 1 C of warming. Sounds like he was not prepared to discuss feedbacks in any detail; not that he’d have much to say, even if he had studied his Lindzen.
As for the impact on crops, it’s hard to make a short and simple argument. Different crops in different locations will be affected differently, and as regional rainfall predictions are not the greatest strength of climate models, there is model uncertainty there as well. But I’d think a farmer would be interested to know the current thinking.
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We’re already starting to see studies that show CO2 and graminaceous C3 crops are a bad mix, with N in grain falling by ~8% in Euro harvests. That is: more CO2, less nutrition in seed. The plant produces less nutritious seeds. We have to plant more acreage to get the same nutrition (or take supplements – maybe Lomborg can help the poor by claiming we need to spend money on vitamins).
Best,
D
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