Dear Fabio,
The direct measurement of d13C of air CO2 by Dave Keeling started only in
the late 1970s. But there are data available from firn and ice core gas
inclusions. I would recommend to use the data of Francey et al. (1999).
They have combined air, firn and ice core data consistently without offsets.
You can also have a look at
http://cdiac.esd.ornl.gov/trends/co2/contents.htm for post-1996 data.
Florian

Francey, R.J., Allison, C.E., Etheridge, D.M., Trudinger, C.M., Enting,
I.G., Leuenberger, M., Langenfelds, R.L., Michel, E., Steele, L.P. (1999):
A 1000-year high precision record of d13C in atmospheric CO2. Tellus, 51B,
170-193


At 16:40 21.06.04, you wrote:
>I'm sorry
>In my last e-mail to IOGEOCHEM
>I've forgot to tell you that I was looking for atmospheric delta 13C
>My apologies
>Fabio
>
>-----Messaggio originale-----
>Da: Fabio Marzaioli [mailto:[log in to unmask]]
>Inviato: lunedì 21 giugno 2004 15.43
>A: Isogeochem ([log in to unmask])
>Oggetto: Delta atm request
>
>Dear all
>I'm looking for atmospheric delta values starting from 1960 to our days...
>Does anybody know where I could find them??
>Thank'U
>
>*********************************************
>     Dott.Fabio Marzaioli Ph Doctor Student
>    Seconda Università degli Studi di Napoli
>      Dipartimento di Scienze Ambientali
>       tel 0823/274511 fax 0823/274605
>      Via Vivaldi,43 81100 Caserta (Italy)
>*********************************************


***************************************************
Florian Boehm
Leibniz-Institut f. Meereswissenschaften, IfM-GEOMAR
FB 2, Marine Biogeochemie/Ostufer
Wischhofstr. 1-3, D-24148 Kiel
Germany
email: [log in to unmask]
http://www.geomar.de/~fboehm/
Tel.: (49)431-600-2104
***************************************************