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***  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.                            ***
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Year   Jan     Feb     Mar     Apr     May     Jun     Jul     Aug     Sep     Oct     Nov     Dec     Ann

1989  -99.99  356.82  357.51  357.90  356.04  352.59  351.03  349.54  349.50  352.40  355.31  356.79  -99.99
1990  356.90  357.59  358.56  358.99  357.23  354.58  352.21  350.09  349.65  352.10  355.11  356.06  354.92
1991  357.61  359.09  359.74  360.82  360.00  357.04  355.02  351.68  349.41  353.18  355.66  356.25  356.29
1992  359.04  360.71  360.61  360.76  359.43  356.76  355.82  353.64  351.01  353.72  357.03  357.77  357.19
1993  358.53  359.42  360.52  361.32  359.47  355.52  352.76  352.76  352.75  354.53  356.99  358.21  356.90
1994  359.51  360.52  361.60  362.70  361.54  358.33  356.50  354.38  353.70  356.57  359.02  360.31  358.72
1995  362.46  363.36  363.80  365.24  364.53  361.22  358.94  356.49  356.31  359.48  362.10  363.43  361.45
1996  364.10  364.55  365.92  366.84  366.49  364.51  361.87  359.45  358.23  360.93  363.52  363.41  363.32
1997  365.28  367.64  367.75  367.74  366.65  364.05  361.65  359.25  358.38  361.43  364.55  365.97  364.20
1998  367.85  369.08  369.74  369.34  367.93  366.35  363.99  362.64  362.81  366.08  369.17  369.01  367.00
1999  370.71  372.18  371.46  370.68  369.78  369.02  366.84  364.29  363.83  366.63  369.68  371.57  368.89
2000  373.21  373.93  373.62  373.68  372.89  370.30  368.43  366.12  364.98  367.32  370.63  372.66  370.65
2001  373.26  373.25  373.59  374.80  373.97  370.71  369.27  367.74  365.91  368.23  372.26  374.71  371.48
2002  376.26  375.66  375.16  375.75  376.65  375.21  371.99  368.76  368.11  371.31  375.36  377.41  373.97

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.