********************************************************************* *** Atmospheric Carbon Dioxide Mixing Ratios from the *** *** NOAA CMDL Carbon Cycle Cooperative Global Air Sampling *** *** Network, 1968-2002 *** *** *** *** March 2005 *** *** *** *** Source: Thomas J. Conway *** *** Pieter P. Tans *** *** NOAA Climate Monitoring and Diagnostics Laboratory *** *** 325 Broadway *** *** Boulder, Colorado, U.S.A. *** ********************************************************************* Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann 1984 -99.99 -99.99 345.68 346.69 346.58 345.55 345.08 344.54 343.81 343.47 344.06 344.89 -99.99 1985 345.35 345.85 346.70 347.07 347.13 347.04 346.33 345.65 345.10 344.52 344.95 346.15 345.99 1986 346.77 347.03 347.76 348.64 348.27 347.85 347.58 346.44 345.83 345.91 345.91 345.84 346.99 1987 346.64 347.88 348.93 349.97 350.38 349.78 348.99 348.73 348.48 348.03 348.20 349.38 348.78 1988 350.42 351.10 351.61 352.01 352.28 351.97 351.23 350.56 350.46 350.70 350.99 351.90 351.27 1989 352.97 353.75 354.72 354.69 353.73 353.60 353.77 353.15 352.34 352.14 352.30 352.88 353.34 1990 354.03 355.23 355.32 354.63 354.72 355.02 354.64 354.24 353.85 353.48 353.63 354.33 354.43 1991 355.12 355.71 356.45 356.59 356.27 356.42 355.90 354.85 354.08 354.31 355.04 355.32 355.51 1992 356.10 356.61 356.87 358.10 358.71 357.89 356.84 355.93 355.42 355.22 355.25 356.02 356.58 1993 356.94 357.12 357.37 358.93 359.47 358.25 357.58 357.37 356.76 356.28 356.62 357.65 357.53 1994 358.69 359.26 359.29 359.45 359.63 359.14 358.42 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 1995 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 360.79 -99.99 1996 361.62 362.33 362.82 362.85 362.77 363.23 363.39 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 1997 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 1998 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 366.18 366.66 -99.99 1999 367.39 368.54 369.81 370.04 368.61 368.37 368.60 367.68 367.03 367.22 367.80 368.53 368.30 2000 369.21 369.89 370.89 372.19 371.99 370.34 369.61 369.24 368.60 368.64 369.18 370.10 369.99 2001 370.73 371.24 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 371.88 -99.99 2002 372.32 372.73 373.79 374.47 374.13 373.62 373.51 373.24 372.75 372.81 373.26 373.87 373.38 Monthly measurements are reported in parts per million (ppm) and are directly traceable to the WMO CO2 mole fraction scale. Annual values are the arithmetic means of the 12 monthly values.