******************************************************************** *** Atmospheric CO2-curve values (ppmv) derived from flask air *** *** samples collected at the Kermadec Islands, Pacific *** *** *** *** Source: R. F. Keeling, S. C. Piper, A. F. Bollenbacher *** *** and S. J. Walker *** *** Carbon Dioxide Research Group *** *** Scripps Institution of Oceanography (SIO) *** *** University of California *** *** La Jolla, California USA 92093-0444 *** *** *** *** May 2008 *** ******************************************************************** Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Ann. Ave. 1983 340.90 340.99 340.86 340.70 340.73 340.98 341.28 341.49 341.62 341.80 342.14 342.55 341.34 1984 342.83 342.80 342.55 342.30 342.27 342.47 342.74 342.93 343.06 343.25 343.61 344.04 342.90 1985 344.33 344.30 344.07 343.80 343.74 343.91 344.16 344.34 344.45 344.63 344.99 345.42 344.35 1986 345.73 345.72 345.49 345.24 345.19 345.38 345.63 345.80 345.91 346.09 346.44 346.88 345.79 1987 347.19 347.21 347.03 346.85 346.88 347.16 347.51 347.79 348.00 348.27 348.70 349.18 347.65 1988 349.52 349.54 349.32 349.08 349.05 349.25 349.52 349.72 349.85 350.04 350.40 350.80 349.67 1989 351.06 350.99 350.72 350.41 350.32 350.46 350.68 350.83 350.92 351.09 351.44 351.86 350.90 1990 352.16 352.15 351.93 351.69 351.66 351.86 352.13 352.32 352.44 352.61 352.95 353.36 352.27 1991 353.64 353.60 353.36 353.08 353.02 353.18 353.42 353.57 353.65 353.79 354.11 354.49 353.58 1992 354.75 354.71 354.46 354.21 354.17 354.36 354.60 354.76 354.82 354.94 355.23 355.57 354.72 1993 355.78 355.68 355.40 355.09 355.02 355.20 355.47 355.67 355.81 356.01 356.38 356.80 355.69 1994 357.08 357.05 356.81 356.55 356.51 356.71 357.00 357.23 357.40 357.63 358.04 358.52 357.21 1995 358.86 358.90 358.72 358.51 358.51 358.73 359.00 359.18 359.28 359.44 359.76 360.14 359.09 1996 360.39 360.33 360.06 359.78 359.72 359.90 360.15 360.32 360.42 360.58 360.93 361.35 360.33 1997 361.63 361.62 361.40 361.16 361.15 361.39 361.70 361.95 362.14 362.41 362.86 363.39 361.90 1998 363.79 363.89 363.78 363.65 363.72 364.02 364.36 364.63 364.81 365.05 365.45 365.92 364.42 1999 366.23 366.24 366.02 365.77 365.74 365.93 366.19 366.37 366.47 366.62 366.93 367.30 366.32 2000 367.53 367.43 367.11 366.78 366.68 366.82 367.05 367.22 367.33 367.50 367.85 368.27 367.30 2001 368.55 368.53 368.31 368.07 368.07 368.31 368.64 368.90 369.09 369.36 369.80 370.32 368.83 2002 370.72 370.81 370.68 370.55 370.62 370.93 371.30 371.60 371.82 372.09 372.54 373.03 371.39 2003 373.39 373.43 373.24 373.03 373.01 373.22 373.49 373.68 373.79 373.98 374.34 374.77 373.61 2004 375.07 375.07 374.85 374.62 374.61 374.83 375.13 375.36 375.52 375.75 376.16 376.64 375.30 2005 376.99 377.04 376.88 376.70 376.75 377.04 377.39 377.68 377.90 378.17 378.61 379.11 377.52 2006 379.47 379.51 379.32 379.10 379.07 379.27 379.53 379.71 379.82 379.99 380.33 380.74 379.66 Values above are taken from a curve consisting of 4 harmonics plus a stiff spline and a linear gain factor, fit to monthly concentration values adjusted to represent 2400 hours on the 15th day of each month. Data used to derive this curve are shown in the accompanying graph. Units are parts per million by volume (ppmv) expressed in the 2003A SIO manometric mole fraction scale. The "annual average" is the arithmetic mean of the twelve monthly values.