MAUNA:(CDIAC ftp server) Monthly atmospheric co2 data from Mauna Loa, through 1991
DATA SET TITLE: ATMOSPHERIC CO2 CONCENTRATIONS - MAUNA LOA OBSERVATORY, HAWAII, 1958-1991.
CONTRIBUTOR: C. D. KEELING SCRIPPS INSTITUTION OF OCEANOGRAPHY UNIVERSITY OF CALIFORNIA LA JOLLA, CA 92093
Contains monthly and annual atmospheric carbon dioxide (CO2) concentrations derived from the Scripps Institution of Oceanography's continuous monitoring program at Mauna Loa Observatory, Hawaii. This record constitutes the longest continuous record of atmospheric CO2 concentrations available in the world. Monthly and annual average mole fractions of CO2 in water-vapor-free air are given from march 1958 through 1991, except for a few interruptions.
The data are here