1. Data Source: C.D. Keeling and T.P. Whorf, Atmospheric CO2 Concentrations (ppmv) derived from in situ air samples collected at Mauna Loa Observatory, Hawaii, Scripps Institute of Oceanography, August 1998. A. Neftel et al, Historical CO2 Record from the Siple Station Ice Core, Physics Institute, University of Bern, Switzerland, September 1994. See http://cdiac.esd.ornl.gov/trends/co2/contents.htm Atmospheric carbon dioxide (CO2) concentrations (1750 to present)

2. Data Source: D.M. Etheridge et al. Concentrations of CH4 from the Law Dome (East Side, "DE08" Site) Ice Core(a), Commonwealth Scientific and Industrial Research Organisation, Aspendale, Victoria, Australia. September 1994. Available: http://cdiac.esd.ornl.gov/ftp/trends/methane/lawdome.259. M.A.K. Khalil, R.A. Rasmussen, and F. Moraes. "Atmospheric methane at Cape Meares: Analysis of a high resolution data base and its environmental implications." Journal of Geophysical Research 98:14,753-14,770. 1993. Available: http://cdiac.esd.ornl.gov/ftp/db1007/cmeares.mon Atmospheric methane (CH4) concentrations

3. Data Sources: United States Department of Energy, Energy Information Administration, International Energy Outlook, 1998 and 1999. How much will the Kyoto Protocol reduce emissions?

4. Stabilization Targets Greenhouse gas emission scenarios

5. Data Source: Marland et al, 1999. Carbon Dioxide Information Analysis Center. Cumulative carbon emissions, 1950-1996

6. Data Source: Marland et al, 1999. Carbon Dioxide Information Analysis Center. Per capita emissions of carbon from industrial sources, 1996