Global Mean CO2 Mixing Ratios (ppm): Observations ---------------------------------------------------------------------------------- Data Data Source Year MixR Yar MixR Source Year MixR Year MixR ---------------------------------------------------------------------------------- Ice- 1850 285.2 1900 295.7 1950 311.3 2000 369.64 Core 1851 285.1 1901 296.2 1951 311.8 2001 371.15 Data 1852 285.0 1902 296.6 1952 312.2 2002 373.15 Adjus- 1853 285.0 1903 297.0 1953 312.6 2003 375.64 ted 1854 284.9 1904 297.5 1954 313.2 NOAA/ 2004 377.44 for 1855 285.1 1905 298.0 1955 313.7 ESRL/ 2005 379.46 Global 1856 285.4 1906 298.4 1956 314.3 annual 2006 381.59 Mean 1857 285.6 1907 298.8 1957 314.8 change 2007 383.37 1858 285.9 1908 299.3 SIO 1958 315.34 added 2008 385.46 1859 286.1 1909 299.7 Mauna 1959 316.18 to 2009 386.95 1860 286.4 1910 300.1 Loa 1960 317.07 2003 2010 389.21 1861 286.6 1911 300.6 & 1961 317.73 data 2011 391.15 1862 286.7 1912 301.0 South 1962 318.43 2012 393.23 1863 286.8 1913 301.3 Pole 1963 319.08 1864 286.9 1914 301.4 Adjus- 1964 319.65 1865 287.1 1915 301.6 ted 1965 320.23 1866 287.2 1916 302.0 for 1966 321.59 1867 287.3 1917 302.4 Global 1967 322.31 1868 287.4 1918 302.8 Mean 1968 323.04 1869 287.5 1919 303.0 1969 324.23 1870 287.7 1920 303.4 1970 325.54 1871 287.9 1921 303.7 1971 326.42 1872 288.0 1922 304.1 1972 327.45 1873 288.2 1923 304.5 1973 329.43 1874 288.4 1924 304.9 1974 330.21 1875 288.6 1925 305.3 CMDL 1975 331.36 1876 288.7 1926 305.8 InSitu 1976 331.92 1877 288.9 1927 306.2 Mauna 1977 333.73 1878 289.5 1928 306.6 Loa 1978 335.42 1879 290.1 1929 307.2 & 1979 337.10 1880 290.8 1930 307.5 South 1980 338.99 1881 291.4 1931 308.0 Pole 1981 340.36 1882 292.0 1932 308.3 1982 341.57 1883 292.5 1933 308.9 CMDL 1983 342.53 1884 292.9 1934 309.3 Flask 1984 344.24 1885 293.3 1935 309.7 Mean 1985 345.72 1886 293.8 1936 310.1 of 1986 347.15 1887 294.0 1937 310.6 Many 1987 348.93 1888 294.1 1938 311.0 Sites 1988 351.47 1889 294.2 1939 311.2 1989 353.15 1890 294.4 1940 311.3 1990 354.29 1891 294.6 1941 311.0 1991 355.68 1892 294.8 1942 310.7 1992 356.42 1893 294.7 1943 310.5 1993 357.13 1894 294.8 1944 310.2 1994 358.61 1895 294.8 1945 310.3 1995 360.67 1896 294.9 1946 310.3 1996 362.58 1897 294.9 1947 310.4 1997 363.48 1898 294.9 1948 310.5 1998 366.27 1899 295.3 1949 310.9 1999 368.38 ----------------------------------------------------------------------------------