*  South Pole, Mauna Loa: C. D. Keeling, T. P. Whorf, and the Carbon Dioxide Research Group, Scripps Institute of Oceanography (SIO), University of California, La Jolla, CA 92093, U.S.A.; Seychelles: Thomas J. Conway, Pieter Tans, Lee S. Waterman, National Oceanic and Atmospheric Administration, Climate Monitoring and Diagnostics Laboratory, 325 Broadway, Boulder CO 80303. See http:// cdiac.esd.ornl.gov/trends/co2/contents.htm.