From rmg3@access5.digex.net Mon Jul  7 12:10:20 EDT 1997
Article: 141995 of sci.environment
Path: news2.digex.net!digex.net!not-for-mail
From: rmg3@access5.digex.net (Robert Grumbine)
Newsgroups: sci.energy,sci.environment,sci.geo.geology,sci.bio.ecology
Subject: Re: CO2 data, current and ice cores
Followup-To: sci.environment
Date: 7 Jul 1997 12:07:47 -0400
Organization: Under construction
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References: <863706597.25723@dejanews.com> <33B97A0B.451E6BAF@math.nwu.edu> <33bdcc29 <33BE829B.1225@patriot.net>
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Xref: news2.digex.net sci.energy:71861 sci.environment:141995 sci.geo.geology:47882 sci.bio.ecology:30947

In article <33BE829B.1225@patriot.net>,
Will Stewart   wrote:
>Sam McClintock wrote:
>> 
>> > The carbon in CO2 exists in two isotopes, C-12 and C-13.  Which
>> > one is highly dependent upon the source.  If you exprapolate, you
>> > will see that the increase in CO2 in the atmosphere is both very
>> > small and not man made.  I can post more details if you think you
>> > can follow it.
>
>Post the details so we can examine your evidence and methods.

  One of several sources is _Tracers in the Sea_ by W. S. Broecker and
T.-H. Peng, Eldigio Press, 1985.

  Mr. McClintock missed an isotope -- C-14 also records the anthropogenic
imprint.

  The crux of the method(s) is that fossil fuel carbon is different than
pre-bomb, pre-industrial carbon.  The carbon in fossil fuels has relatively
less carbon 13 than the free atmosphere because plants preferentially
use the slightly more reactive carbon 12.  The carbon in fossil fuels
also has zero carbon 14 because the carbon 14 decays much faster than
the fossil fuel spends underground.  Between the two, you have independant
measures of the influx of fossil fuel-derived carbon to the atmosphere.
Observations of carbon isotope ratios as well as atmospheric carbon
dioxide levels now extend for 40 years as direct measurements, and 
confirm fossil fuel combustion as the source.

  But _don't_ take my word for it.  Read the scientific literature, 
starting with the textbook I name above.  

  Followup to sci.environment

-- 
Robert Grumbine rmg3@access.digex.net
Sagredo (Galileo Galilei) "You present these recondite matters with too much 
evidence and ease; this great facility makes them less appreciated than they 
would be had they been presented in a more abstruse manner." Two New Sciences