Does anyone know of the latest literature that provides actual
measurements of the ratio of 13C to 12C in the atmospheric CO2 reservior,
especially for recent (200) years when fossil fuel combustion has been
changing it? I am looking for an empirical relationship that I can apply
for a correction factor for some tree ring work. Thanks Valerie Barber

Valerie Barber
Institute of Marine Science
O'Neill 200
University of Alaska Fairbanks
Fairbanks, AK 99775
work phone (907) 474-7899
fax (907) 474-7204