4 488 Weighted smoothing spline fit Ice core and Mauna Loa CO2, extended past 1990.5 with OCMIP3 data, and past 2002 with HG's data 50% attenuation at 23.4968 ; REG = 100.000 Time Smoothed data Deriv 1765.0 277.9514 0.02688 1765.5 277.9652 0.02828 1766.0 277.9797 0.02969 1766.5 277.9949 0.03111 1767.0 278.0108 0.03253 1767.5 278.0275 0.03395 1768.0 278.0448 0.03539 1768.5 278.0628 0.03682 1769.0 278.0816 0.03827 1769.5 278.1011 0.03972 1770.0 278.1213 0.04118 1770.5 278.1423 0.04264 1771.0 278.1640 0.04411 1771.5 278.1864 0.04559 1772.0 278.2096 0.04707 1772.5 278.2335 0.04855 1773.0 278.2581 0.05005 1773.5 278.2835 0.05155 1774.0 278.3097 0.05305 1774.5 278.3366 0.05457 1775.0 278.3642 0.05608 1775.5 278.3927 0.05761 1776.0 278.4218 0.05914 1776.5 278.4518 0.06067 1777.0 278.4825 0.06222 1777.5 278.5140 0.06376 1778.0 278.5463 0.06532 1778.5 278.5793 0.06688 1779.0 278.6132 0.06845 1779.5 278.6478 0.07002 1780.0 278.6832 0.07160 1780.5 278.7194 0.07318 1781.0 278.7564 0.07477 1781.5 278.7942 0.07637 1782.0 278.8327 0.07797 1782.5 278.8721 0.07958 1783.0 278.9123 0.08120 1783.5 278.9533 0.08282 1784.0 278.9951 0.08445 1784.5 279.0378 0.08608 1785.0 279.0812 0.08772 1785.5 279.1255 0.08937 1786.0 279.1706 0.09102 1786.5 279.2165 0.09268 1787.0 279.2633 0.09434 1787.5 279.3109 0.09601 1788.0 279.3593 0.09769 1788.5 279.4085 0.09937 1789.0 279.4586 0.10106 1789.5 279.5096 0.10275 1790.0 279.5614 0.10445 1790.5 279.6140 0.10616 1791.0 279.6676 0.10787 1791.5 279.7219 0.10959 1792.0 279.7772 0.11131 1792.5 279.8332 0.11303 1793.0 279.8902 0.11475 1793.5 279.9480 0.11647 1794.0 280.0067 0.11820 1794.5 280.0662 0.11992 1795.0 280.1266 0.12164 1795.5 280.1878 0.12336 1796.0 280.2499 0.12508 1796.5 280.3129 0.12681 1797.0 280.3767 0.12853 1797.5 280.4414 0.13020 1798.0 280.5069 0.13176 1798.5 280.5732 0.13322 1799.0 280.6401 0.13458 1799.5 280.7077 0.13583 1800.0 280.7759 0.13697 1800.5 280.8447 0.13802 1801.0 280.9139 0.13895 1801.5 280.9836 0.13979 1802.0 281.0537 0.14051 1802.5 281.1241 0.14114 1803.0 281.1948 0.14166 1803.5 281.2657 0.14207 1804.0 281.3369 0.14238 1804.5 281.4081 0.14258 1805.0 281.4794 0.14268 1805.5 281.5508 0.14268 1806.0 281.6221 0.14257 1806.5 281.6933 0.14235 1807.0 281.7644 0.14204 1807.5 281.8354 0.14161 1808.0 281.9060 0.14108 1808.5 281.9764 0.14045 1809.0 282.0465 0.13971 1809.5 282.1161 0.13887 1810.0 282.1853 0.13793 1810.5 282.2540 0.13687 1811.0 282.3222 0.13572 1811.5 282.3897 0.13446 1812.0 282.4566 0.13309 1812.5 282.5228 0.13162 1813.0 282.5882 0.13005 1813.5 282.6528 0.12837 1814.0 282.7166 0.12659 1814.5 282.7794 0.12470 1815.0 282.8412 0.12271 1815.5 282.9021 0.12061 1816.0 282.9619 0.11841 1816.5 283.0205 0.11610 1817.0 283.0779 0.11380 1817.5 283.1343 0.11160 1818.0 283.1896 0.10952 1818.5 283.2438 0.10756 1819.0 283.2971 0.10570 1819.5 283.3495 0.10396 1820.0 283.4011 0.10233 1820.5 283.4519 0.10081 1821.0 283.5020 0.09940 1821.5 283.5513 0.09810 1822.0 283.6001 0.09692 1822.5 283.6483 0.09584 1823.0 283.6959 0.09488 1823.5 283.7432 0.09404 1824.0 283.7900 0.09330 1824.5 283.8365 0.09267 1825.0 283.8827 0.09216 1825.5 283.9286 0.09176 1826.0 283.9745 0.09148 1826.5 284.0201 0.09133 1827.0 284.0658 0.09132 1827.5 284.1115 0.09143 1828.0 284.1573 0.09168 1828.5 284.2032 0.09206 1829.0 284.2494 0.09257 1829.5 284.2958 0.09321 1830.0 284.3426 0.09399 1830.5 284.3898 0.09489 1831.0 284.4375 0.09593 1831.5 284.4857 0.09710 1832.0 284.5346 0.09840 1832.5 284.5842 0.09984 1833.0 284.6345 0.10140 1833.5 284.6856 0.10310 1834.0 284.7376 0.10493 1834.5 284.7906 0.10689 1835.0 284.8445 0.10898 1835.5 284.8995 0.11120 1836.0 284.9557 0.11356 1836.5 285.0131 0.11604 1837.0 285.0718 0.11866 1837.5 285.1318 0.12141 1838.0 285.1932 0.12429 1838.5 285.2561 0.12731 1839.0 285.3206 0.13045 1839.5 285.3866 0.13373 1840.0 285.4543 0.13682 1840.5 285.5233 0.13941 1841.0 285.5936 0.14149 1841.5 285.6647 0.14307 1842.0 285.7366 0.14415 1842.5 285.8088 0.14472 1843.0 285.8812 0.14480 1843.5 285.9535 0.14436 1844.0 286.0255 0.14362 1844.5 286.0971 0.14278 1845.0 286.1683 0.14185 1845.5 286.2390 0.14080 1846.0 286.3091 0.13966 1846.5 286.3786 0.13842 1847.0 286.4475 0.13707 1847.5 286.5157 0.13563 1848.0 286.5831 0.13412 1848.5 286.6498 0.13259 1849.0 286.7157 0.13103 1849.5 286.7808 0.12946 1850.0 286.8451 0.12786 1850.5 286.9087 0.12623 1851.0 286.9714 0.12459 1851.5 287.0332 0.12292 1852.0 287.0943 0.12123 1852.5 287.1544 0.11952 1853.0 287.2138 0.11778 1853.5 287.2722 0.11602 1854.0 287.3298 0.11424 1854.5 287.3865 0.11243 1855.0 287.4423 0.11072 1855.5 287.4972 0.10921 1856.0 287.5515 0.10790 1856.5 287.6052 0.10680 1857.0 287.6583 0.10590 1857.5 287.7111 0.10520 1858.0 287.7635 0.10471 1858.5 287.8158 0.10442 1859.0 287.8680 0.10433 1859.5 287.9202 0.10444 1860.0 287.9725 0.10476 1860.5 288.0250 0.10529 1861.0 288.0778 0.10601 1861.5 288.1310 0.10694 1862.0 288.1848 0.10808 1862.5 288.2392 0.10941 1863.0 288.2942 0.11095 1863.5 288.3501 0.11269 1864.0 288.4070 0.11464 1864.5 288.4648 0.11679 1865.0 288.5238 0.11914 1865.5 288.5840 0.12170 1866.0 288.6455 0.12438 1866.5 288.7084 0.12710 1867.0 288.7726 0.12986 1867.5 288.8382 0.13266 1868.0 288.9053 0.13550 1868.5 288.9737 0.13838 1869.0 289.0437 0.14131 1869.5 289.1151 0.14427 1870.0 289.1880 0.14731 1870.5 289.2624 0.15043 1871.0 289.3384 0.15365 1871.5 289.4160 0.15696 1872.0 289.4954 0.16036 1872.5 289.5764 0.16386 1873.0 289.6592 0.16745 1873.5 289.7439 0.17113 1874.0 289.8304 0.17490 1874.5 289.9188 0.17876 1875.0 290.0092 0.18266 1875.5 290.1014 0.18654 1876.0 290.1957 0.19039 1876.5 290.2918 0.19422 1877.0 290.3899 0.19802 1877.5 290.4898 0.20180 1878.0 290.5917 0.20556 1878.5 290.6954 0.20929 1879.0 290.8010 0.21294 1879.5 290.9083 0.21646 1880.0 291.0174 0.21985 1880.5 291.1281 0.22310 1881.0 291.2405 0.22622 1881.5 291.3543 0.22921 1882.0 291.4697 0.23206 1882.5 291.5864 0.23478 1883.0 291.7044 0.23736 1883.5 291.8237 0.23981 1884.0 291.9442 0.24213 1884.5 292.0658 0.24431 1885.0 292.1885 0.24636 1885.5 292.3122 0.24827 1886.0 292.4368 0.25006 1886.5 292.5622 0.25170 1887.0 292.6884 0.25322 1887.5 292.8154 0.25460 1888.0 292.9430 0.25577 1888.5 293.0711 0.25667 1889.0 293.1996 0.25729 1889.5 293.3284 0.25764 1890.0 293.4572 0.25771 1890.5 293.5860 0.25750 1891.0 293.7147 0.25701 1891.5 293.8430 0.25625 1892.0 293.9709 0.25521 1892.5 294.0982 0.25389 1893.0 294.2247 0.25230 1893.5 294.3504 0.25043 1894.0 294.4751 0.24828 1894.5 294.5987 0.24587 1895.0 294.7210 0.24350 1895.5 294.8422 0.24152 1896.0 294.9626 0.23993 1896.5 295.0822 0.23874 1897.0 295.2014 0.23793 1897.5 295.3202 0.23751 1898.0 295.4390 0.23749 1898.5 295.5578 0.23785 1899.0 295.6769 0.23861 1899.5 295.7964 0.23974 1900.0 295.9167 0.24127 1900.5 296.0378 0.24320 1901.0 296.1599 0.24552 1901.5 296.2834 0.24822 1902.0 296.4082 0.25132 1902.5 296.5348 0.25481 1903.0 296.6631 0.25869 1903.5 296.7935 0.26297 1904.0 296.9261 0.26735 1904.5 297.0609 0.27158 1905.0 297.1977 0.27564 1905.5 297.3365 0.27955 1906.0 297.4772 0.28322 1906.5 297.6196 0.28661 1907.0 297.7637 0.28972 1907.5 297.9093 0.29254 1908.0 298.0562 0.29508 1908.5 298.2043 0.29734 1909.0 298.3535 0.29931 1909.5 298.5036 0.30099 1910.0 298.6545 0.30249 1910.5 298.8061 0.30390 1911.0 298.9584 0.30522 1911.5 299.1113 0.30645 1912.0 299.2648 0.30759 1912.5 299.4189 0.30864 1913.0 299.5734 0.30960 1913.5 299.7285 0.31047 1914.0 299.8839 0.31124 1914.5 300.0397 0.31193 1915.0 300.1958 0.31252 1915.5 300.3522 0.31301 1916.0 300.5088 0.31342 1916.5 300.6656 0.31377 1917.0 300.8225 0.31406 1917.5 300.9796 0.31428 1918.0 301.1368 0.31445 1918.5 301.2941 0.31456 1919.0 301.4514 0.31460 1919.5 301.6087 0.31459 1920.0 301.7659 0.31451 1920.5 301.9232 0.31438 1921.0 302.0803 0.31418 1921.5 302.2373 0.31393 1922.0 302.3942 0.31352 1922.5 302.5508 0.31288 1923.0 302.7071 0.31200 1923.5 302.8628 0.31088 1924.0 303.0179 0.30953 1924.5 303.1723 0.30794 1925.0 303.3258 0.30611 1925.5 303.4783 0.30404 1926.0 303.6298 0.30174 1926.5 303.7800 0.29920 1927.0 303.9290 0.29642 1927.5 304.0764 0.29340 1928.0 304.2224 0.29034 1928.5 304.3668 0.28744 1929.0 304.5098 0.28470 1929.5 304.6515 0.28212 1930.0 304.7920 0.27969 1930.5 304.9312 0.27743 1931.0 305.0694 0.27532 1931.5 305.2066 0.27337 1932.0 305.3428 0.27158 1932.5 305.4782 0.26995 1933.0 305.6128 0.26854 1933.5 305.7468 0.26744 1934.0 305.8803 0.26665 1934.5 306.0135 0.26615 1935.0 306.1465 0.26596 1935.5 306.2795 0.26606 1936.0 306.4126 0.26652 1936.5 306.5461 0.26737 1937.0 306.6801 0.26861 1937.5 306.8148 0.27025 1938.0 306.9503 0.27227 1938.5 307.0871 0.27469 1939.0 307.2251 0.27750 1939.5 307.3647 0.28070 1940.0 307.5059 0.28430 1940.5 307.6490 0.28828 1941.0 307.7943 0.29266 1941.5 307.9417 0.29743 1942.0 308.0917 0.30259 1942.5 308.2444 0.30815 1943.0 308.3999 0.31409 1943.5 308.5586 0.32043 1944.0 308.7204 0.32707 1944.5 308.8857 0.33392 1945.0 309.0544 0.34098 1945.5 309.2267 0.34824 1946.0 309.4026 0.35572 1946.5 309.5824 0.36340 1947.0 309.7661 0.37129 1947.5 309.9538 0.37939 1948.0 310.1455 0.38771 1948.5 310.3415 0.39623 1949.0 310.5418 0.40495 1949.5 310.7465 0.41389 1950.0 310.9557 0.42307 1950.5 311.1696 0.43253 1951.0 311.3883 0.44228 1951.5 311.6119 0.45230 1952.0 311.8406 0.46260 1952.5 312.0746 0.47318 1953.0 312.3139 0.48403 1953.5 312.5587 0.49518 1954.0 312.8091 0.50661 1954.5 313.0653 0.51837 1955.0 313.3275 0.53044 1955.5 313.5958 0.54284 1956.0 313.8704 0.55555 1956.5 314.1514 0.56858 1957.0 314.4390 0.58193 1957.5 314.7334 0.59560 1958.0 315.0347 0.60959 1958.5 315.3430 0.62388 1959.0 315.6585 0.63804 1959.5 315.9810 0.65162 1960.0 316.3099 0.66381 1960.5 316.6444 0.67386 1961.0 316.9835 0.68234 1961.5 317.3266 0.68973 1962.0 317.6732 0.69690 1962.5 318.0236 0.70463 1963.0 318.3782 0.71432 1963.5 318.7385 0.72734 1964.0 319.1062 0.74415 1964.5 319.4833 0.76520 1965.0 319.8721 0.79053 1965.5 320.2745 0.81982 1966.0 320.6922 0.85082 1966.5 321.1253 0.88150 1967.0 321.5737 0.91230 1967.5 322.0377 0.94364 1968.0 322.5174 0.97540 1968.5 323.0131 1.00753 1969.0 323.5248 1.03910 1969.5 324.0520 1.06919 1970.0 324.5937 1.09719 1970.5 325.1487 1.12245 1971.0 325.7158 1.14566 1971.5 326.2941 1.16739 1972.0 326.8828 1.18696 1972.5 327.4806 1.20375 1973.0 328.0859 1.21674 1973.5 328.6966 1.22492 1974.0 329.3108 1.23247 1974.5 329.9296 1.24343 1975.0 330.5549 1.25849 1975.5 331.1889 1.27843 1976.0 331.8340 1.30228 1976.5 332.4917 1.32905 1977.0 333.1631 1.35614 1977.5 333.8474 1.38102 1978.0 334.5436 1.40309 1978.5 335.2500 1.42178 1979.0 335.9649 1.43752 1979.5 336.6871 1.45076 1980.0 337.4153 1.46149 1980.5 338.1481 1.46964 1981.0 338.8848 1.47710 1981.5 339.6254 1.48577 1982.0 340.3708 1.49623 1982.5 341.1221 1.50913 1983.0 341.8802 1.52378 1983.5 342.6460 1.53934 1984.0 343.4197 1.55558 1984.5 344.2017 1.57231 1985.0 344.9922 1.58983 1985.5 345.7917 1.60840 1986.0 346.6006 1.62762 1986.5 347.4193 1.64719 1987.0 348.2476 1.66505 1987.5 349.0837 1.67902 1988.0 349.9257 1.68760 1988.5 350.7702 1.68933 1989.0 351.6200 1.70000 1989.5 352.4700 1.70000 1990.0 353.3200 1.70000 1990.5 354.1700 1.70000 1991.0 354.9666 -999 1991.5 355.4840 -999 1992.0 355.9125 -999 1992.5 356.2656 -999 1993.0 356.4832 -999 1993.5 356.9545 -999 1994.0 357.6902 -999 1994.5 358.6209 -999 1995.0 359.6369 -999 1995.5 360.6260 -999 1996.0 361.5229 -999 1996.5 362.3600 -999 1997.0 362.8839 -999 1997.5 363.4538 -999 1998.0 364.7527 -999 1998.5 366.5040 -999 1999.0 367.6363 -999 1999.5 368.1512 -999 2000.0 368.5849 -999 2000.5 369.4103 -999 2001.0 370.3523 -999 2001.5 371.0773 -999 2002.0 371.9717 -999 2002.5 373.1636 -999 2003.0 374.4362 -999 2003.5 375.43 -999 2004.0 376.44 -999 2004.5 377.45 -999 2005.0 378.46 -999 2005.5 379.48 -999 2006.0 380.49 -999 2006.5 381.51 -999 2007.0 382.51 -999 2007.5 383.52 -999 2008.0 384.52 -999 2008.5 385.52 -999