date: 23 Dec 1996 16:20:33 -0700 from: Tom Wigley subject: Re: MAG Output to: Mike Hulme RE>>MAG Output 12/23/96 Dear Mike, The CO2HIST.IN file I sent, which says "as used by IPCC1995" is the correct one to use. The Etheridge file is an updated (and better data set)---but this is not the one you should use. Happy Christmas and best wishes, Tom -------------------------------------- Date: 12/20/96 5:41 PM To: Tom Wigley From: Mike Hulme Received: by qgate.ucar.edu with SMTP;20 Dec 1996 17:39:50 -0700 Received: from cpca2.uea.ac.uk by mailgate1.uea.ac.uk with SMTP (PP); Sat, 21 Dec 1996 00:28:56 +0000 Received: from atbara.cru.uea.ac.uk by cpca2.uea.ac.uk; (5.65/1.1.8.2/29Jun95-0305PM) id AA09425; Sat, 21 Dec 1996 00:28:43 GMT Message-Id: <1.5.4.16.19961221003157.0e2714c2@pop.uea.ac.uk> X-Sender: f037@pop.uea.ac.uk X-Mailer: Windows Eudora Light Version 1.5.4 (16) Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Sat, 21 Dec 1996 00:31:57 +0000 To: Tom Wigley From: Mike Hulme Subject: Re: MAG Output Tom, Sorry about the output size. Mike is using a compressed format o/p to save paper - it is obviously too compressed! Looking through your data files there is a difference between the CO2HIST.IN files pre-1964. Your concs. are lower than ours (sometimes by 2-3ppmv) over most of the pre-1964 period. Your file states 'as used by IPCC1995' whereas ours says 'as given in Etheridge et al. and merged with IPCC1995 data, March 1996.' Also, MAG.F was altered 26 February 1996 to read CO2 history from the file CO2HIST.IN rather than from a DATA statement. These differences would explain the different CO2 forcing in your and our runs, a difference which diminshes to near zero during the 21st century (consistent with the fact noted above that i/p CO2 concentrations after 1964 are identical). Should we be using your CO2HIST.IN file or the one we have? The other difference I can find is, as you say, due to Mike having ITAUMETH set at 2 rather than 3. This alters the CH4 and TROPO3 forcing after 1990. I now have the MAG code from Mike and the other matters now seem clearer to me. If you can confirm this is the likely difference then please email me your CO2HIST.IN file and we can test it (the one in the email has lots of carriagecontrols in it) or else you can try get our results using our CO2HIST.IN file below. We will change ITAUMETH to 3. I hope this resolves the issue. Merry Christmas to you and Astrid and the children. We say Helen Dorday the other day and she sent her greetings to you and Astrid. MIke 1764 277.487 1765 277.607 1766 277.732 1767 277.862 1768 277.997 1769 278.137 1770 278.282 1771 278.432 1772 278.586 1773 278.744 1774 278.905 1775 279.070 1776 279.237 1777 279.405 1778 279.575 1779 279.745 1780 279.915 1781 280.087 1782 280.261 1783 280.439 1784 280.621 1785 280.809 1786 281.001 1787 281.195 1788 281.392 1789 281.590 1790 281.788 1791 281.985 1792 282.179 1793 282.371 1794 282.559 1795 282.743 1796 282.921 1797 283.093 1798 283.257 1799 283.411 1800 283.556 1801 283.691 1802 283.817 1803 283.933 1804 284.041 1805 284.141 1806 284.233 1807 284.317 1808 284.392 1809 284.459 1810 284.518 1811 284.573 1812 284.625 1813 284.675 1814 284.725 1815 284.775 1816 284.825 1817 284.875 1818 284.925 1819 284.973 1820 285.017 1821 285.055 1822 285.080 1823 285.089 1824 285.076 1825 285.040 1826 284.981 1827 284.898 1828 284.795 1829 284.675 1830 284.541 1831 284.393 1832 284.231 1833 284.059 1834 283.885 1835 283.730 1836 283.600 1837 283.495 1838 283.420 1839 283.385 1840 283.395 1841 283.445 1842 283.535 1843 283.660 1844 283.810 1845 283.975 1846 284.145 1847 284.320 1848 284.495 1849 284.659 1850 284.810 1851 284.945 1852 285.075 1853 285.210 1854 285.350 1855 285.500 1856 285.659 1857 285.825 1858 285.990 1859 286.150 1860 286.305 1861 286.445 1862 286.575 1863 286.700 1864 286.815 1865 286.930 1866 287.050 1867 287.170 1868 287.300 1869 287.445 1870 287.610 1871 287.795 1872 288.000 1873 288.235 1874 288.510 1875 288.825 1876 289.175 1877 289.575 1878 290.020 1879 290.490 1880 290.970 1881 291.450 1882 291.915 1883 292.355 1884 292.760 1885 293.120 1886 293.435 1887 293.705 1888 293.930 1889 294.115 1890 294.270 1891 294.395 1892 294.505 1893 294.610 1894 294.710 1895 294.825 1896 294.965 1897 295.140 1898 295.360 1899 295.625 1900 295.935 1901 296.280 1902 296.650 1903 297.040 1904 297.445 1905 297.855 1906 298.265 1907 298.675 1908 299.080 1909 299.480 1910 299.865 1911 300.235 1912 300.590 1913 300.925 1914 301.250 1915 301.570 1916 301.890 1917 302.215 1918 302.545 1919 302.880 1920 303.225 1921 303.580 1922 303.950 1923 304.340 1924 304.750 1925 305.180 1926 305.620 1927 306.070 1928 306.535 1929 307.005 1930 307.470 1931 307.930 1932 308.385 1933 308.825 1934 309.230 1935 309.590 1936 309.895 1937 310.130 1938 310.290 1939 310.365 1940 310.370 1941 310.325 1942 310.250 1943 310.175 1944 310.120 1945 310.100 1946 310.130 1947 310.220 1948 310.375 1949 310.600 1950 310.913 1951 311.315 1952 311.787 1953 312.313 1954 312.883 1955 313.495 1956 314.135 1957 314.795 1958 315.474 1959 316.172 1960 316.881 1961 317.600 1962 318.331 1963 319.083 1964 319.865 1965 320.692 1966 321.574 1967 322.517 1968 323.525 1969 324.594 1970 325.716 1971 326.883 1972 328.086 1973 329.311 1974 330.555 1975 331.834 1976 333.163 1977 334.544 1978 335.965 1979 337.415 1980 338.885 1981 340.371 1982 341.880 1983 343.420 1984 344.992 1985 346.601 1986 348.193 1987 349.768 1988 351.335 1989 352.865 1990 354.407 YEAR CONC END OF YEAR CONCS AS GIVEN IN ETHERIDGE ET AL AND MERGED WITH IPCC95 DATA SET, MARCH 1996 At 17:35 19/12/96 -0700, you wrote: >If you want me to check your MAG output, please think about whether I will be >able to read what you fax me. The MAG.OUT data you sent me were too small >(reduced size) for me to read. Also, as I've said before, please read the >code. There is one obvious error you have made --- in the value of ITAUMETH >in MAGUSER.CFG. If you read the bottom of this file, it tells you what to use >(viz. 3, not 2). I flagged problems in methane (as used in the IPCC >calculations) to you in a previous message. > >When I run MAG with your wrong ITAUMETH, I still don't get your numbers. As >far as I can see, we have different forcings too --- but I can't read your >output so I can't say this for sure. > >Since I get the correct IPCC numbers using your version of MAG.FOR, and since >(when corrected) we have the same .CFG files, the difference must be in the >other input details. Some of these files are attached; plus others to help >you see what the correct numbers should be. > >Cheers, >Tom > > ><<<<<< Attached TEXT file named "ABRKDN.DAT" follows >>>>>> >Emissions profile: IS95A Date: 9 Sep 1995 > > > ----------------------------------------------------------------------------- Dr Mike Hulme tel: +44 1603 593162 Climatic Research Unit fax: +44 1603 507784 School of Environmental Sciences email: m.hulme@uea.ac.uk University of East Anglia web site: http://www.cru.uea.ac.uk/~mikeh/ Norwich NR4 7TJ Mean temps. in C.England during 1996: about 0.2degC below the 1961-90 average. The maximum temperature in Norwich: Wednesday 18 December: 8.1degC.