******************************************************************* *** Atmospheric CO2 concentrations (ppmv) derived from flask *** *** and in situ air samples collected at the South Pole *** *** *** *** Source: C.D. Keeling *** *** T.P. Whorf, and the Carbon Dioxide Research Group *** *** Scripps Institution of Oceanography (SIO) *** *** University of California *** *** La Jolla, California USA 92093-0444 *** *** *** *** May 2005 *** *** *** ******************************************************************* Year Jan. Feb. Mar. Apr. May Jun. July Aug. Sept. Oct. Nov. Dec. Annual Annual-Fitted 1957 -99.99 -99.99 -99.99 -99.99 -99.99 313.37 -99.99 -99.99 313.87 -99.99 -99.99 314.48 -99.99 -99.99 1958 -99.99 -99.99 314.29 -99.99 -99.99 314.52 -99.99 -99.99 315.31 -99.99 -99.99 -99.99 -99.99 314.78 1959 315.09 315.14 315.09 -99.99 -99.99 -99.99 -99.99 315.96 316.22 -99.99 316.32 -99.99 -99.99 315.64 1960 -99.99 -99.99 -99.99 -99.99 -99.99 316.38 316.69 316.75 -99.99 -99.99 -99.99 -99.99 -99.99 316.45 1961 -99.99 -99.99 -99.99 -99.99 316.79 316.86 316.94 317.35 317.68 317.74 317.87 317.67 -99.99 317.08 1962 317.45 317.26 317.06 317.11 317.18 317.25 317.27 317.64 318.07 -99.99 -99.99 318.63 (317.62) 317.62 1963 318.13 317.87 317.47 317.90 318.26 318.22 318.26 318.64 318.56 319.02 -99.99 -99.99 (318.32) 318.35 1964 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 -99.99 318.68 1965 -99.99 318.68 318.56 318.68 318.89 -99.99 319.38 319.67 -99.99 -99.99 320.17 320.27 -99.99 319.42 1966 320.34 319.99 320.05 320.31 320.44 320.46 -99.99 321.08 321.35 321.46 321.56 321.07 (320.74) 320.72 1967 -99.99 321.01 -99.99 320.86 321.00 320.96 321.06 321.83 322.08 321.80 321.82 321.77 (321.33) 321.32 1968 321.53 -99.99 -99.99 321.61 321.47 321.44 321.50 -99.99 -99.99 -99.99 -99.99 322.65 -99.99 321.91 1969 322.37 -99.99 322.27 322.30 322.58 322.79 323.24 323.60 324.13 323.95 323.97 -99.99 (323.11) 323.12 1970 323.68 323.53 323.43 323.67 323.78 324.18 324.46 324.72 325.19 325.20 325.23 -99.99 (324.34) 324.32 1971 324.80 324.61 324.33 324.47 324.67 324.91 325.15 -99.99 325.77 -99.99 325.74 -99.99 -99.99 325.12 1972 -99.99 -99.99 325.05 325.17 325.31 325.82 326.13 326.85 326.54 326.79 326.94 326.82 (326.00) 326.00 1973 326.74 326.34 326.36 326.82 327.11 327.43 327.73 328.40 328.69 328.63 328.60 328.58 327.62 327.62 1974 328.30 328.08 328.09 327.90 328.01 327.88 328.46 328.68 328.94 329.04 329.12 328.99 328.46 328.49 1975 328.89 328.90 328.85 328.94 328.93 329.07 329.35 329.83 330.22 330.56 330.46 330.27 329.52 329.50 1976 330.30 330.01 329.91 329.63 329.93 329.98 330.46 331.01 331.39 331.71 331.74 331.43 330.62 330.60 1977 331.26 331.00 330.85 331.32 331.40 331.62 332.05 332.45 332.87 333.10 333.31 333.18 332.03 332.03 1978 332.83 332.71 332.83 332.98 -99.99 333.37 333.82 334.28 334.74 334.82 334.58 334.30 (333.70) 333.69 1979 334.01 334.03 333.82 334.17 334.34 334.54 335.15 335.71 335.88 336.00 336.37 336.04 335.01 335.03 1980 336.06 335.75 -99.99 336.10 336.21 336.90 337.45 337.54 337.87 337.90 337.97 338.04 (336.98) 336.98 1981 337.76 337.48 337.43 337.52 337.67 338.15 338.41 338.76 338.81 339.15 338.86 338.91 338.24 338.26 1982 -99.99 338.65 338.38 338.70 338.99 339.18 339.33 340.11 340.30 340.33 340.03 339.96 (339.39) 339.39 1983 339.86 339.84 339.85 340.31 340.63 341.00 341.41 341.88 342.33 342.29 342.54 342.35 341.19 341.17 1984 342.05 -99.99 341.71 341.84 341.87 342.01 342.80 343.20 343.46 343.50 343.32 343.15 (342.56) 342.58 1985 343.01 342.83 342.73 342.76 343.12 343.45 343.93 344.52 344.86 344.95 344.79 344.64 343.80 343.82 1986 344.63 344.57 344.50 344.62 344.69 345.02 345.54 345.93 346.18 346.16 346.17 346.04 345.34 345.32 1987 345.89 345.79 345.75 346.11 346.20 346.61 347.19 347.63 348.07 348.10 348.19 348.31 346.99 346.99 1988 348.29 348.06 347.87 348.20 348.33 348.58 349.07 349.58 349.75 349.89 349.85 349.83 348.94 348.95 1989 349.81 349.76 349.66 349.73 349.93 350.18 350.59 351.12 351.37 351.30 351.33 350.99 350.48 350.44 1990 350.76 350.40 350.64 350.90 351.36 351.59 352.05 352.55 352.75 352.57 352.83 352.63 351.75 351.77 1991 -99.99 352.34 352.28 352.44 352.54 352.96 353.39 353.67 354.09 353.89 353.95 353.77 (353.15) 353.12 1992 353.56 353.15 353.03 353.23 353.74 354.00 354.61 354.94 355.26 355.37 355.11 354.88 354.24 354.24 1993 354.72 354.49 354.22 354.42 354.50 354.84 355.20 355.70 356.04 356.05 356.02 355.69 355.16 355.16 1994 355.49 355.49 355.51 355.63 355.69 355.99 356.47 357.11 357.61 357.53 357.71 357.52 356.48 356.48 1995 357.45 357.36 357.36 357.63 357.81 357.95 358.34 358.75 359.15 359.29 359.43 359.47 358.33 358.35 1996 359.36 359.30 359.25 359.36 359.40 359.71 360.15 360.52 360.71 360.70 360.74 360.70 359.99 359.99 1997 360.56 360.46 360.32 360.48 360.58 360.90 361.24 361.52 361.95 362.01 362.11 362.15 361.19 361.20 1998 362.10 362.30 362.41 362.69 363.00 363.54 364.04 364.56 364.99 365.02 365.10 364.98 363.73 363.70 1999 364.96 364.75 364.81 364.99 365.05 -99.99 365.66 365.92 366.37 366.51 366.74 366.80 (365.66) 365.65 2000 366.46 366.49 366.76 366.45 366.58 366.78 367.10 367.53 367.65 367.75 367.88 367.83 367.10 367.05 2001 367.81 367.10 367.04 367.36 367.60 367.92 368.29 368.83 369.44 369.57 369.46 369.25 368.31 368.34 2002 369.31 369.50 369.61 369.68 369.99 370.38 370.87 371.46 371.69 371.83 371.81 371.61 370.64 370.66 2003 371.93 371.78 371.71 371.99 372.32 372.57 372.96 373.40 373.90 373.82 373.65 373.61 372.80 372.80 2004 373.59 373.41 373.85 373.88 374.06 374.46 374.85 375.35 375.52 375.60 375.51 375.25 374.61 374.61 Monthly values are expressed in parts per million (ppm) and reported in the 2003A SIO manometric mole fraction scale. The monthly values have been adjusted to the 15th of each month. Missing values are denoted by -99.99. The "annual" average is the arithmetic mean of the twelve monthly values. In years with one or two missing monthly values, annual values were calculated by substituting a fit value (4-harmonics with gain factor and spline) for that month and then averaging the twelve monthly values.