Hello Tom,

Maybe the following article is what you've been looking for:

Clark-Thorne, S.T., and Yapp, C.J. (2003) Stable carbon isotope constraints on mixing and mass blance of CO2 in an urban atmosphere: Dalla metropolitan area, TExas, USA, Applied Geochemistry, v. 18, p. 1991-2004.

Neil Tabor
Assistant Professor
Department of Geological Sciences
Southern Methodist University
Dallas, TX 75275-0395
Phone (214) 768-4175
FAX (214) 768-2701



-----Original Message-----
From: Stable Isotope Geochemistry on behalf of Thomas L. Millican
Sent: Wed 2/7/2007 8:23 AM
To: [log in to unmask]
Subject: [ISOGEOCHEM] atmospheric carbon istope paper
 
Hello All,
I was told of a journal article discussing the isotope ratio of carbon in the atmosphere. Supposedly, the article links the increased atmospheric CO2 concentration to anthropogenic sources through this carbon isotope ratio. 
Unfortunately, after a couple of weeks of looking for this article, I have been unable to find it. Has anyone else come across such an article? Either my searching technique is really lacking, or it doesn't exist (the article).
Thanks,
-Tom Millican


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University of Arkansas Stable Isotope Laboratory
http://www.uark.edu/ua/isotope/