NOTE: This post is the second in the series from Dr. Roy Spencer of the National Space Science and Technology Center at University of Alabama, Huntsville. The first, made last Friday, was called Atmospheric CO2 Increases: Could the Ocean, Rather Than Mankind, Be the Reason?
Due to the high interest and debate his first post has generated, Dr. Spencer asked me to make this second one, and I’m happy to oblige.
Here is part2 of Dr. Spencer’s essay on CO2 without any editing or commentary on my part.
(Side note: Previously, I erroneously reported that Dr. Spencer was out of the country. Not so. That was my mistake and a confusion with an email autoresponse from another person named “Roy”. Hence this new update.)
More CO2 Peculiarities: The C13/C12 Isotope Ratio
Roy W. Spencer
January 28, 2008
In my previous post, I showed evidence for the possibility that there is a natural component to the rise in concentration of CO2 in the atmosphere. Briefly, the inter-annual co-variability in Southern Hemisphere SST and Mauna Loa CO2 was more than large enough to explain the long-term trend in CO2. Of course, some portion of the Mauna Loa increase must be anthropogenic, but it is not clear that it is entirely so.
Well, now I’m going to provide what appears to be further evidence that there could be a substantial natural source of the long-term increase in CO2.
One of the purported signatures of anthropogenic CO2 is the carbon isotope ratio, C13/C12. The “natural” C13 content of CO2 is just over 1.1%. In contrast, the C13 content of the CO2 produced by burning of fossil fuels is claimed to be slightly smaller – just under 1.1%.
The concentration of C13 isn’t reported directly, it is given as “dC13”, which is computed as:
“dC13 = 1000* {([C13/C12]sample / [C13/C12]std ) – 1
The plot of the monthly averages of this index from Mauna Loa is shown in Fig. 1.
Now, as we burn fossil fuels, the ratio of C13 to C12 is going down. From what I can find digging around on the Internet, some people think this is the signature of anthropogenic emissions. But if you examine the above equation, you will see that the C13 index that is reported can go down not only from decreasing C13 content, but also from an increasing C12 content (the other 98.9% of the CO2).
If we convert the data in Fig. 1 into C13 content, we find that the C13 content of the atmosphere is increasing (Fig. 2).
So, as the CO2 content of the atmosphere has increased, so has the C13 content…which, of course, makes sense when one realizes that fossil-fuel CO2 has only very slightly less C13 than “natural” CO2 (about 2.6% less in relative terms). If you add more CO2, whether from a natural or anthropogenic source, you are going to add more C13.
The question is: how does the rate of increase in C13 compare to the CO2 increase from natural versus anthropogenic sources?
First, lets look at the C13 versus C12 for the linear trend portion of these data (Fig. 3).
The slope of this line (1.0952%) represents the ratio of C13 variability to C12 variability associated with the trend signals. When we compare this to what is to be expected from pure fossil CO2 (1.0945%), it is very close indeed: 97.5% of the way from “natural” C13 content (1.12372%) to the fossil content.
At this point, one might say, “There it is! The anthropogenic signal!”. But, alas, the story doesn’t end there.
If we remove the trend from the data to look at the inter-annual signals in CO2 and C13, we get the curves shown in Figures 4 and 5.
Note the strong similarity – the C13 variations very closely follow the C12 variations, which again (as in my previous post) are related to SST variations (e.g. the strong signal during the 1997-98 El Nino event).
Now, when we look at the ratio of these inter-annual signals like we did from the trends in Fig. 3, we get the relationship seen in Fig. 6.
Significantly, note that the ratio of C13 variability to CO2 variability is EXACTLY THE SAME as that seen in the trends!
BOTTOM LINE: If the C13/C12 relationship during NATURAL inter-annual variability is the same as that found for the trends, how can people claim that the trend signal is MANMADE??
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RE my first March 2/08 post:
Here is my guess of average atmospheric CO2 readings for the next 6-8 months. Note that Global CO2 data is now available to end December 2007, and Mauna Loa data is available to end February 2008. There is room for improvement – starting from raw data, this work took ~1 to 2 hours:
Prediction of Atmospheric CO2 (ppm)
Year Mo Global M.Loa
2008 1 385.1 385.4
2008 2 385.2 385.8
2008 3 385.5 386.3
2008 4 385.7 388.1
2008 5 385.5 388.1
2008 6 384.5 387.5
2008 7 382.7 385.8
2008 8 381.4 383.2
Best regards, Allan
Dear Allan,
Herewith my detailed forecast on CO2 levels in the atmosphere (both global and Mauna Loa) for the monthly averages in 2008:
Year Mo Glob MLO
2008 1 384.2 385.4
2008 2 384.8 385.8
2008 3 385.4 386.2
2008 4 385.8 388.1
2008 5 385.7 388.3
2008 6 384.6 387.6
2008 7 382.9 385.9
2008 8 381.8 383.6
2008 9 382.2 382.5
2008 10 383.7 383.1
2008 11 385.4 384.5
2008 12 386.6 386.2
That is for the case that the temperatures remain lower than average as seen in January this year. Not much difference with your predicition.
If the temperatures go back to the previous years’ average e.g. from June on, we have these series:
Year Mo Glob MLO
2008 1 384.2 385.4
2008 2 384.8 385.8
2008 3 385.4 386.2
2008 4 385.8 388.1
2008 5 385.7 388.3
2008 6 385.3 388.3
2008 7 383.6 386.6
2008 8 382.5 384.3
2008 9 382.9 383.2
2008 10 384.4 383.8
2008 11 386.1 385.2
2008 12 387.3 386.9
Formula: 2008.month = 2007.month + 2.2 ppmv (from 8.6 Gt emissions in 2008) + 3 ppmv * dT (2008.month – 2007.month).
Regards,
Ferdinand
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The upper surface ocean holds d13 at ~+1, Atmosphere ~-7% due to the mixing of CO2 from plants which has been fractionated.
So if increase due to offgasing from surface oceans would ^ ratio and will have as the temperature increases?
Whereas the ratio has gone more negative so must be vegation source ancient or recent.
Probably both and it is countering the oceans positive effect and man’s CO2 is going somewhere and only 40% into atmosphere.
The rise is from man lets get over this.
Anthony
There is some C12/13 empirical data that might be of interest to Roy Spencer.
http://cat.inist.fr/?aModele=afficheN&cpsidt=13839192
Maybe if Roy contacted me direct…
Just a small point: C12/C13 ratios in coal and petroleum are different because coal is the fossilised remains of the total plant whereas petroleum is the fossilised remains of the plant lipids (oils) and these lipids contain lower amounts of C13 than the rest of the plant.
We began burning petroleum in large quantities around 1960, so since then I would expect to see very small differences accumulating in the general C12/C13 ratio of air.
Dear Roy
You are missing the main point, shown by the average graph at
http://cdiac.ornl.gov/trends/co2/iso-sio/graphics/isomlogr.jpg, and also if you look at it closely, by your own graph
The C13 ratio stays constant over most of the Mauna Loa record and falls suddenly whenever there is an El Niño event. There is no correpondence with the smooth, regular increase shown by the measured CO2 concentration.
The only explanation is that the emissions, which come only from a restricted region of industrial activity, take time to mix sufficiently to reach the oceans where the measurements are made, so that initially they displaces gas which has already been mixed; with the same constant C13 ratio. It is only when there is more rapid mixing because of the El Niño that the emitted CO2 gets to the ocean measurement equipment, and thus causes a sudden drop in C13 ratio, followed by another flat period at a lowere level.
This means that CO2 ia NOT “well-mixed” in the atmosphere; that concentrations near idustrial areas regularly have higher figures than those foubd over the ocean, and that the figures documented by Beck are genuine.
It also means that greenhouse models based on behaviour over the oceans are not appropriate for land surfaces, which have different CO2 concentrations. It is amazing to me that nobody seems to want to actually measure them.
First, let us see some references about the C13 ratio of different plants and different fossil fuels. Are the averages for each really all that different?
Second, why is the progress downwards of the C13 ratio intermittent? This suggests that at least one source is being mixed in more slowly than another. The most likely candidate for slow mixing is the fossil fuel emission which occurs only over a limied latitude region. The “natural” seasonal change is more widespread, but that also happens quicker near to the land-based sources.
Third, what does Roy thinks happens to the emissions? Do they suddenly get “sunk” somewhere before they get to Mauna Loa?
Fourth, Allen Mcrae suggest that you cannot believe in the simultaneous influence of natutal and anthropogenic sources. If this is so it is the IPCC in reverse. They believe that ALL changes are anthropogenic. Can you really believe that ALL changes are natural?
Fifth. Where does the CO2 increase actually come from and why does it go up in a linear fashion whether the temperature goes up or down. It cannot be related to temperature. What is it related to?
Mr. Watts,
I have tried twice to post a reply here, only to come to a page with the word “discarded”.
blue
REPLY: I have no idea why that would happen. This one obviously got through. I don’t manage the server, WordPress.com does. It could be any number of things, but given that I have no other similar complaints in the 65,000+ comments poste dhere, I’ll have to assume it is something local to your connection or computer. Often routing does strange things. If you have a DSL or other type modem for your connection, try resetting it. – Anthony
Dear Dr. Spencer,
your conclusion
is fundamentally flawed. The equality of the two slopes, that you base your conclusion on, is a mathematical necessity and not a characteristic of the data; it holds true for any two randomly selected data sets.
This fact has been brought to my attention
by a post by Tamino
To illustrate the point made by Tamino, I have taken the liberty to replicate your analysis with two other data sets:
Dow Jones Index, 1990-1999 (1990=100)
Gold price in USD, 1970-1979
The plots can be found here:
Raw data
“Trend”
“Interannual”
Derivatives were calculated as the difference to the preceding month, multiplied by 12 to give annual rates.
As expected, the slopes of the “Trend Signal” and the “Interannual Signal” are identical.
Upon request, I will e-mail Mr. Watts the excel spreadsheet. However, this behavior can be shown with any pair of time series.
Please look into this subject.
The original post is already a year old, so few readers are going to notice this comment on their own. I would recommend to post a heads-up as prominently as the original post, so that none of the blog’s readers relies on this faulty line of reasoning.
blue
Found the problem. The original comment contained some URLs, which I by now have encapsulated in HTML anchor tags.
Hi blue,
It’s taken me a while to find this thread again, even though you posted here only today. There doesn’t seem to be much interest on this board in the explication of a fundamental error in Dr Spencer’s analysis. That’s curious, don’t you think?
~snip~ I wonder whether or not Anthony Watts will think it to be something of enough interest to return to? It does seem to me that if a scientist who has been very expressive here has made such a mistake then it should be of interest – but perhaps I am not understanding what determines the ‘interest’ of this blog?
I’ll let Dr. Spencer know, Mr. “Talbot”. Any chance that you would consider your own integrity important enough (while you question mine) to stop using a fabricated name? – Anthony Watts
Yes, I also think this is worth re visiting, I’d like to see Dr Spencer address the critique.
I’ll let Dr. Spencer know, Mr. “Talbot”. Any chance that you would consider your own integrity important enough (while you question mine) to stop using a fabricated name? – Anthony Watts
Hmm – is ‘Steven Goddard’, for example, a genuine name? My name is not fabricated, though it is not a simple statement of my first and last name. I did mistakenly use a different (entirely genuine) first name for a few posts when I was posting from another computer, which you seem to have picked up on.
I don’t think the truth of this matter depends upon my posting name. It is entirely obvious that very many post here under posting names which are not their ‘legal’ names. You do not seem to challenge those others. However, if you think I should use my legal first and last names, then say so, and I will.
Meanwhile I look forward to Dr Spencer’s response to this matter.
REPLY: AFAIK Steven Goddard is a true name. You obviously haven’t looked deep enough to see where I have challenged others here on the same issue. My question is simple. Why do you have one name for posting, yet your email linked to the same posting (here, this one, not previously) uses an entirely different name? When people challenge my integrity, and the integrity of Dr. Spencer, but have a need to use two different names, it does not help that person’s credibility here. Explanation please. – Anthony Watts
Dr. Spencer seemed to have a different conclusion on his own blog.
REPLY: That post on his blog was written AFTER this one, and after he the benefit of a trip to Mauna Loa. – Anthony
My question is simple. Why do you have one name for posting, yet your email linked to the same posting (here, this one, not previously) uses an entirely different name?
An explanation of that is irrelevant in this context (irrelevant in the sense that I have no professional connection with the suibject of this debate) but, as you can see, I will now post under my legal name as challenged. My previous posting names were, in fact, entirely genuine names of mine.
Can I anticipate that you will make the same challenge to ‘Smokey’, Jeff ID’, ‘oldconstructionworker’;, etc.? Or is this only a challenge you make to those who take views contrary to yours?
REPLY: Thank you for coming clean as to who you are. But I am puzzled by this:
“My previous posting names were, in fact, entirely genuine names of mine.”
How many “genuine” names is a person allowed? To my knowledge, the only “genuine” name is the one that exists on the birth certificate, or certificate of a court approved name change later in life. Your statement is rubbish of the most exceptional sorts.
I challenge those who question my integrity, while at the same time not having enough integrity themselves to use their own name, as you have demonstrated. Steve Talbot now becomes Simon Evans. None of those people you mention above has challenged my integrity, nor Dr. Spencer’s. Further, none of them has changed names or handles as you have. I know who they are. While you may not consider this detail of knowing whom you are dealing with important, I do. Science is not done anonymously. Integrity and anonymity are not compatible bedfellows. If you want to question the word of an established scientist, I think it is only fair that you use your own name. Otherwise, why would he bother to respond? If you do not like how I operate this venue, please choose another.
As I mentioned, I’ll pass your request onto Dr. Spencer. It is up to him if he chooses to respond. – Anthony Watts
How many “genuine” names is a person allowed? To my knowledge, the only “genuine” name is the one that exists on the birth certificate, or certificate of a court approved name change later in life. Your statement is rubbish of the most exceptional caliber.
The names ‘Steven Talbot’ are on my birth certificate. Can you please explain further what your issue is with that?
If you want to question the word of an established scientist, I think it is only fair that you use your own name.
Very well, I have done so, unlike the great majority of the people who post here. Do you have a further issue with this or are you now satisfied?
I stand by what I have said, under any combination of my genuine names. I would have the integrity to answer to it, including any acceptance of having been in error. You can have my word on that, though that may not be of much substance to you.
Of coyrse it is up to Dr Spencer whether he chooses to respond. I look forward to the outcome of that with interest,
Also, taking Simon’s example, maybe “Tamino” will take a cue and put his name forward. I’d have a lot more respect for him if he did so. I find the whole “attack others from a comfortable veil of anonymity” to be cowardly and mostly counterproductive. – Anthony Watts
Anthony,
You state above that “AFAIK Steven Goddard is a true name.” I accept without question that, AFAYK, that is the case. However, I do not know that it is the case, and I do not know that you know it either.
There can be reasons not to post under one’s legal name which are entirely unrelated to the debate in question. For example, imagine a teacher. let’s say, whose name might be googled by students. I will post under my legal name in future, but I continue to wonder why your challenges are directed only against those with whom you disagree.
Of course, what would be of much more interest is further discussion of the issue in question, in respect of this thread.
REPLY: I think it premature to assume that I disagree with you on this issue. If Dr. Spencer agrees to post a followup, we may very well find ourselves in agreement. Remember, this post is a year old. And what you don’t know is all of the previous issues like this I’ve dealt with. Some people who regularly frequent here have decided that using their real name is a good thing (after I made a post on the issue that covered everyone) and do so now when they post here. Some people whom have made repeated attempts to change identities for the purpose of covertly causing discord have been banned. I just don’t have time nor patience for those sorts of shenanigans. I do feel it is important to be open and honest in this debate, using real names is a courtesy of the most basic kind in civil debate, especially when one person challenges another on their work. – Anthony
blue:
Dr. Spencer refutes Tamino: click. Old thread, but interesting.
Also [since I’m mentioned above], let me point out two things:
First, I am certainly not immune from Anthony’s criticism. When he sees something wrong he lets people know, no matter who they are.
Second, a big problem [as I see it] is someone posting under multiple names. That is deceptive. I do all my posts under the name I use here [I won’t go into the reason for the name I use, but I’ve explained it privately]. I don’t post comments under various names. I don’t argue with myself under various assumed names, and I don’t use other names to make it appear that my position is shared by others.
I can’t speak for Anthony, but from my point of view, using multiple names for posting comments seems devious.
And for the record, Anthony has had my full [real] name, address and telephone number for a long time now. Those with fake and alternate names could avoid some of the criticism by providing the same information. What have you got to hide?
I find it interesting, that none of the comments so far looks into the simple math I have shown. Anyone who knows how to use a spreadsheet program can easily replicate the results with any two randomly picked time series.
@Smokey: Dr. Spencer may or may not “refute Tamino”, but that post you link to does not address the line of reasoning expressed in this post here. Here Dr. Spencer posited, that the equality of the two slopes is strong evidence, that the rise in atmospheric CO2 concentrations is not man made. Tamino has shown – and I have demonstrated it here – that the equality of the two slopes is not, repeat not, a characteristic of the data sets. So this single argument of Dr. Spencer fails. Nothing more, nothing less.
To all: I simply do value my anonymity. I have chosen ONE alias – and made it obvious it is an alias – to use on this site and Tamino’s, Rabett’s, RC, you name it. If it was “blue”, it was me. I have done and will do all my posts under that moniker. I have been polite, made no accusations, refrained from second guessing motives of others and have not misbehaved in any way I am aware of. I let facts speak for themselves, anything I have commented on was verifiable with minimum effort. I’m not connected to the field of climate research, so I simply fail to see, how attaching my real life name adds anything to my argument. I don’t have anything to hide, but my name does not add anything to this debate.
I motion to drop this side track on identity and come back to the math.
P.S.: Mr. Watts, I had not realized how important it is to you, to know the real life name of posters. I still value my anonymity online, but I don’t have a problem with revealing my name to you, as long as you keep my personal informations confidential. If you want to know my name, drop me an e-mail, you’ve got my address from my posts.
Motion fails for lack of a second. See, the site owner has a legitimate concern with posters who disparage him, his site, and those who voluntarily contribute articles. Using multiple aliases to make it appear that their position has more support than it does, and to question the site owner’s integrity, and to attack other posters from the safe vantage point of a fake, untraceable and anonymous name are legitimate concerns.
We are in the site owner’s house, and common courtesy dictates that we conform to his wishes. There are literally millions of other blogs out there, where people can say and do just about anything they want. The winner of this year’s best legal blog has numerous posters who routinely brag about all the different aliases they use. But they’re lawyers, so I expect some of them to be manipulators.
Maybe the other finalists would have done better if they didn’t tolerate name calling, and if they didn’t arbitrarily censor comments they didn’t agree with, and if they didn’t act like juveniles by removing all the vowels from posts that disagree with the AGW party line. Most people are turned off by that kind of intolerance.
It doesn’t seem to me that you fall under any of these categories. I can only speak for myself, but it doesn’t appear that comments about multiple posting names were being addressed to you.
One of the best features of this site is the honesty and courtesy of the commenters. IMHO, that went a long way toward making WUWT the winner of Best Science blog. Maybe the other finalists would have done better if they didn’t tolerate name calling, and if they didn’t arbitrarily censor comments they didn’t agree with, and if they didn’t act like juveniles by removing all the vowels from posts that disagreed with the AGW party line. Most people are turned off by that kind of intolerance. Note that last year’s best science blog winner also demands courtesy, and welcomes different points of view, rather than censoring them.
My apologies for rambling a little, but it’s 3 a.m. here and insomnia strikes again. Anyway, probably less than a half dozen people will see this year-old thread, so like you I’m just venting a little. I think if other posters were as polite as you, there wouldn’t be a problem. But some folks take advantage of the internet’s anonymity to say things they wouldn’t otherwise say if their identities were known.
Smokey:
“I can only speak for myself, but it doesn’t appear that comments about multiple posting names were being addressed to you.”
Point taken. When I read your post at (16:41:10 2008/01/20), I was under the impression that all of it was addressed to me.
…”a big problem [as I see it] is someone posting under multiple names. That is deceptive.”
FWIW, I entirely agree. As I explained above, for a few posts I mistakenly mangled my posting names on a computer that was not mine. I am now posting under my legal name, since Mr Watts has effectively challenged me to do so. You are not, which is fine by me.
As for your remarks about disparaging comments, I refer you to the frequency of comments on this site insinuating that Hansen, Mann, etc. are fraudsters. I have not noted you calling anyone to account over that. Such comments are not just disparaging, of course, they are libelous. Anthony Watts has snipped a comment of mine above since he thought it questioned Dr Spencer’s integrity. I don’t think it did, but I can hardly quote myself to make that point. Let me put it another way, now that Anthony Watts has informed Dr Spencer of this matter raised here I look forward to Dr Spencer’s commenting on it.
As for what makes a good or bad science blog, I would suggest that a determination to examine the science would be a part of it. So, let’s examine the science here. The problem with Dr Spencer’s analysis seems clear. I hope he will comment, but in advance of that, do you have anything to say about the science?
Anthony,
Thank you for your response to 16:02:46 above. In respect of this, I entirely agree with you:
Some people whom have made repeated attempts to change identities for the purpose of covertly causing discord have been banned.
I wholly agree that we must take personal responsibility for what we say on the internet.