********************************************************************* *** 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 1991 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 354.70 356.22 -99.99 1992 356.53 356.64 357.46 358.78 359.44 358.62 356.66 353.56 352.88 353.93 354.96 356.68 356.35 1993 358.13 359.10 359.94 360.63 360.48 359.08 357.15 354.30 352.86 354.44 357.15 358.59 357.65 1994 359.11 359.39 359.87 361.04 361.76 360.71 358.21 355.45 354.90 355.97 357.27 358.66 358.53 1995 360.25 361.83 362.83 363.48 364.52 365.11 362.45 358.70 357.91 358.64 360.56 362.89 361.60 1996 364.57 365.34 365.11 365.86 366.65 365.57 363.00 360.00 358.32 359.29 360.81 362.44 363.08 1997 363.92 364.67 365.61 366.48 366.46 364.70 362.09 360.76 360.31 361.49 363.33 365.06 363.74 1998 366.28 366.99 -99.99 -99.99 -99.99 -99.99 -99.99 364.96 364.10 364.17 366.67 369.28 -99.99 1999 369.81 370.06 371.05 371.12 370.82 370.65 368.32 364.84 364.33 365.56 367.04 368.72 368.53 2000 370.20 371.06 371.95 373.19 373.33 371.90 369.41 366.68 366.85 368.38 369.49 370.77 370.27 2001 371.82 372.30 373.53 375.25 375.47 373.05 370.19 368.38 367.62 369.08 371.81 372.43 371.74 2002 373.10 375.13 375.79 375.64 374.88 373.36 371.70 369.77 369.06 370.08 371.75 373.34 372.80 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.