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??
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Mr. Talbot-Evans said:
As the lawyers say, “Truth is a defense.”
IMHO, Hansen is either engaging in fraud, or he is incompetent. I also believe that the reason he avoids taking legal action against any of the many other people here and elsewhere who have said the same thing is because of the discovery process, in which his house of cards would come crashing down in a very public way. Even the New York Times would be forced to cover the story, if Hansen decided to sue his detractors.
In a legal deposition Hansen would be forced to answer questions under oath; questions that he has gone to great lengths to avoid, even calling those who disagree with him “court jesters,” as he scurried away from any debate.
Many of his associates would also be deposed, and a martinet like Hansen has surely stepped on a lot of toes. The truth would emerge, and the truth would not be favorable to James Hanson or NASA, or the UN/IPCC, or the new U.S. President.
Also, it seems to me there is a difference between someone who guest posts on this site, and a public figure who rejects any opportunity to do the same, but only takes pot shots from the sidelines. Questioning someone’s integrity who writes a guest column is a different situation than questioning the ethics of a public figure. And as I recall, you had some choice words for Viscount Monckton, whose posts have appeared here.
Finally, you asked if I have “anything to say about the science.” Um, Steven, or Simon, or whatever your current appellation is, I invite you to comb through the threads here and re-read the numerous comments I’ve made regarding the subject of the Best Science site. I should point out that I only responded when you gratuitously mentioned my name here, in an effort to deflect from questions about your use of multiple names. Where’s the ‘science’ in your comment above?
When I first became aware of the issue of screen names here, I emailed the site owner and explained the reason I would like to use the name I’ve been using. We discussed different possibilities, and at that time I provided full and complete personal information [my true name, address, and phone number], and a summary of my temperature/humidity related work experience with my employer of 30 years prior to my retirement.
Maybe if you had been similarly forthcomingr, instead of game playing with multiple screen names, you wouldn’t have been called to account. But your explanations coming after the fact look lame.
blue,
Thanks for re-reading my post. As you can see, it wasn’t directed at you, since you don’t use multiple names.
OK folks, anyone can have the last word, this subject is exhausted for me. I’m moving on to see how La Niña is doing.
Cheers.
Smokey,
I note with amazement how little time it has taken for you to expose the paucity of your comments on the ‘courtesy’ of this site. I am now posting under my legal name in response to Anthony Watts’ preference, yet you seek to sneer at me for doing so. I have not engaged in “game playing with multiple screen names”. that is a totally false and scurrilous accusation, and I will judge your comments on Hansen in the light of that. You express the opinion of someone who promulgates falsehoods about others.
I note that you continue to have nothing to say about the science in question. Your modus operandi seems to consist entirely of seeking to smear, regardless of the truth.
Anthony Watts,
If you happen to read this, I seek your advice. You can check the history of my posting here and know that my account of it is true. I have changed to posting under my legal name, in response to your comments, but the outcome of that is that I am now subject to scurrilous insinuations from one of your regular posters. If that’s the way things work on this site then I can learn that lesson and spend my time better in other ways. At the moment, I am feeling that it was a mistake to respond to your suggestion, since it seems to allow ‘Smokey’ to promulgate false character attacks. The entire approach here is to substitute discussion of the science with ad hominem attacks as a diversion. I would hope that you would not wish that to be the character of your discussion threads.
REPLY: I suggest that BOTH of you just move on to other topics. I don’t have time to be a referee in personal disputes between people at odds on this blog. – Anthony
Dr. Spencer has chosen to respond on his own blog. I suspect he will continue to do so since when this post on WUWT was made, he did not have his own website for this purpose, and I gladly lent him mine in this instance.
See:
Increasing Atmospheric CO2: Manmade…or Natural?
January 21st, 2009 by Roy W. Spencer, Ph. D.
http://www.drroyspencer.com/
Dr. Spencer has chosen to respond on his own blog.
Except, of course, he doesn’t respond.
REPLY: The man responded with a new post within 24 hours. Next day service does not impress you? That seems petty. – Anthony
He doesn’t respond to the issue that has been raised. No, writing a new post and not responding directly to the issue does not impress me. I refer you to topics posted here by you which laud the good practice of scientists facing up directly to criticism and either resolving it or else admitting to mistake. That would impress me, as it seemed to impress you.
REPLY: Well as I mentioned yesterday, when challenged by a phantom, such as Tamino, who criticizes from the safety behind a veil of anonymity, he could choose not to respond at all. I think his response today, ignoring such anonymity, speaks to the issue well. Besides, he says that if anyone can find anything wrong with it, email him and he’ll post a correction. Seems like a response to me.
I note Dr. James Hansen does not respond even to named people doing quality work out in the open, such as Steve McIntyre, who makes all his source code and methods public, and has the courage to put his name to his work. Neither does Dr. Michael Mann respond to McIntyre. Why is that? I note you are not complaining about their lack of responses to valid issues on replication, data quality, and errors. In light of that, I’ll repeat my assertion that your complaint about the way Dr. Spencer responded within 24 hours seems rather petty.
Dr. Spencer has a standing offer of correction, which is far more than Hansen or Mann has ever done. I suggest you take him up on it, and if you find an error with Dr. Spencer’s essay, challenge him on it!
I’ll even offer to forward your email if you can’t find it on his website. – Anthony
I note Dr. James Hansen does not respond even to named people doing quality work out in the open, such as Steve McIntyre, who makes all his source code and methods public, and has the courage to put his name to his work. Neither does Dr. Michael Mann respond to McIntyre. Why is that?
It’s simple – Hansen and Mann are not posting on your blog. If they were to, then it would be reasonable to expect them to respond. I would not expect Spencer to respond to comments had he not posted here in a public forum. If he doesn’t wish to respond then that is, of course, up to him, but it remains true that he has posted publicly inviting discussion and has not responded to this.
I’m quite likely to email Dr Spencer, so thanks for the offer, but I’ll cover that. I would have raised with him some other errors that used to be on his site (for example, the mislabelling of graphs on the ‘Temperature of the last 2,000 years page’), but he appears to have updated that.
I’m not aware of Hansen or Mann generally speculating on blogs about hypotheses untested in the scientific literature. It seems to me that Spencer is keen to do this. Given that appears to be his chosen medium, it does not seem unreasonable to me to look for a ‘review process’ in the same context. Nobody is going to publish a paper in Nature refuting something Dr Spencer has said on a blog. Either it’s addressed in a context such as this or it is not addressed at all. Equivalently, scientists are free to publish any criticisms of Hansen’s or Mann’s work in the context where they have invited dialogue.
REPLY: Ah, but Mann has posted on RC, and Steve McIntyre has made challenges there that have gone unanswered. Hansen has posted on his personal webpage, and Steve M. has made challenges to claims there, also unanswered. These two scientists can’t even bring themselves to say McIntyre’s name when asked by members of the public in Q&A forums and interviews. Mann is so stubborn on this issue, that he can’t even bring himself to fix obviously wrong latitude-longitude data on locations in his own SI that McIntyre has pointed out. Please don’t try to raise the defense that they are unaware of the work McIntyre has done, or that it somehow doesn’t matter because it is not published, because if they are truly good scientists, and an error is pointed out, they should respond to it. Mann’s case is particularly bad, because the error is so simple, so elementary, and has gone on since MBH 98 that it has become the running joke of the climate forums.
I remain unimpressed with your complaint, Spencer responded within 24 hours, in the same type of medium as the challenge was made. If “Tamino” was not a phantom, and did not sprinkle his challenge with snark, I could well imagine Dr. Spencer may have made a direct reference. IMHO such bad behavior should not be rewarded with official recognition. As I said before, basic courtesy applies. For you to claim that Spencer’s choice of medium for the response is unsatisfactory because it isn’t a peer review process is totally bollocks.
Besides, there is much to be gained from posting an essay on a blog, the wide variety of disciplines of the people reading it, and the level of scrutiny is often higher and most certainly faster than some journal peer reviews, which can take months. Blog publishing provides a good way to get fast feedback, spot problems, and correct them early on before such work would be sent to a journal. – Anthony
Anthony,
I would hardly call Spencer’s new posting a “response”. He is simply throwing out a new argument without either acknowledging the old argument that he made nor any critique of it. And, frankly, I don’t think this new argument is going to stand up to scrutiny much better than the old one did! [Does he seriously believe that each 1 deg change in temperature will result in a change in the rate of CO2 increase or decrease by 1.7 ppm/yr?!? If that were the case, the paleoclimate record would show these gargantuan changes in CO2 as temperatures moved around!]
And, you seem to be excusing Spencer’s behavior by arguing that the scientists like Hansen and Mann and so forth who have been vilified by the skeptic community don’t behave well either. However, even if that were really the case, does it excuse Spencer not trying to set a much better example by coming clean on whether his previous argument was incorrect or not?
REPLY: “Excusing Spencer’s behavior?” You’ve gone off the rails on that comment. If you have problems with “Spencer’s behavior”, take it up with him. Use his email as he offered. I have better things to do than moderate complaints over “how” Dr. Spencer responded. He responded, you just don’t like the response. Thread closed, I’m done with this argument. – Anthony