The following SLP anomalies (in tenths mb, for example, -9 is -0.9mb)
are with respect to 1950-79.
Monthly SLP anomalies exhibit significant month to month variability,
but I have not filtered the following values.
Data
The data is the same in all three formats.
jan feb mar apr may jun jul aug sep oct nov dec
1855 -9 -9 -2 8 0 6 16
1856 -11 -1 8 11 15 5 7 18 14 -2 16 12
1857 24 14 11 17 10 -13 1 7 10 15 22 9
1858 9 8 -19 3 -2 5 10 -8 -3 13 17 28
1859 -28 -21 -9 -4 -25 -9 -6 -6 -4 -4 -10
1860 5 -20 -15 -44 -5 7
1861 16 4 -1 -1 8 8 4 1 5 14 6 13
1862 22 7 -4 0 1 -5 14 10 9 9 2 -18
1863 -4 -14 -14 -1 4 7 7 6 -8 -5 -9 -5
1864 1 -18 -14 -12 0 -20 -1 1 1 9 2 11
1865 -11 7 14 9 -3 -13 0 16 -5 -3 -4 -12
1866 -2 -4 -3 -4 -1 -2 -5 9 -5 1 15 2
1867 15 -1 10 10 4 -5 4 2 -5 -16 5 -10
1868 -6 -3 -18 9 -4 -10 -3 -13 -16 -12 -7 13
1869 -23 3 12 -1 4 2 16 -1 -3 0 0 -5
1870 -4 -8 1 9 5 -3 -1 3 -3 -5 -7 -7
1871 -16 3 -14 -3 -3 2 4 6 6 -6 -5 16
1872 22 9 8 13 9 2 14 2 33 14 31 22
1873 23 30 37 27 28 8 4 1 -6 -22 -4 0
1874 15 10 10 9 9 -10 -1 14 23 15 7 -2
1875 11 -3 4 13 6 12 -10 -1 -1 -11 -20 -15
1876 8 9 -14 -1 8 16 4 18 13 -11 -8 7
1877 -12 -18 -20 -25 -17 -20 2 -3 -11 -8 -6 -13
1878 -14 -19 -24 -8 -1 -6 11 22 11 2 15 11
1879 14 16 16 14 -1 13 20 22 22 16 2 -18
1880 2 17 15 12 9 9 13 23 18 16 19 3
1881 -10 -6 17 19 -6 -7 4 -6 -12 -20 -1 4
1882 -14 -6 5 -8 -6 -19 -31 -37 -27 -11 9 2
1883 23 -18 -34 8 13 3 -17 -9 -16 1 -11 -37
1884 -16 -4 13 -1 4 10 -3 -12 -10 7 -1 -26
1885 -24 0 16 10 14 -9 4 -12 5 -12 -2 6
1886 13 -7 12 2 3 2 -1 4 10 12 7 -3
1887 19 3 11 2 -7 5 12 3 10 12 -3 16
1888 -16 -1 -2 -18 -10 -14 -17 -8 -11 -10 -11 8
1889 -27 14 -28 6 0 13 1 3 6 0 2 12
1890 20 20 16 2 3 -4 -9 -12 0 -4 5 0
1891 23 -7 -5 12 12 4 2 6 1 8 4 4
1892 6 -8 3 12 21 16 13 2 -8 0 -18 3
1893 13 6 18 11 21 15 20 15 16 0 12 -4
1894 13 16 12 11 -3 4 15 -24 -2 6 -10 6
1895 2 18 5 18 16 -8 -13 -18 -11 -10 10 -13
1896 0 4 -12 -14 -14 -22 -17 -15 -17 -10 -7 -8
1897 -12 -9 -11 -8 -6 -1 5 4 -2 3 -11 2
1898 12 -3 -3 10 3 -7 11 9 3 -4 -16 -5
1899 18 23 8 2 -4 -7 -4 -16 2 21 32 0
1900 -1 0 -27 -9 -4 25 7 -5 -33 -31 -8 -1
1901 0 7 14 9 5 20 24 18 -18 -39 -5 -4
1902 30 9 24 17 29 9 11 -8 -15 2 13 4
1903 -2 -4 12 18 12 2 -6 0 6 1 -3 10
1904 24 21 10 19 10 -3 -12 4 2 -8 -14 8
1905 -5 -25 -26 -18 -16 -18 -24 -6 -13 -15 -9 -16
1906 -7 -12 0 -5 -9 -9 -1 20 15 5 14 0
1907 -1 -8 0 -5 -2 -4 -6 -14 1 -7 -8 -4
1908 -3 7 -12 -1 4 -2 20 1 28 7 -1 -15
1909 -11 4 -21 -14 -2 17 8 5 -7 -6 5 2
1910 -8 16 13 -7 3 13 20 5 10 14 11 14
1911 -3 -6 6 -7 -1 -2 -15 -13 -13 -8 -3 -3
1912 -9 -13 -14 -5 -1 -9 -12 -9 -15 -9 2 -6
1913 -10 -7 -8 -7 5 1 6 -12 -4 -4 -6 -8
1914 10 22 14 -13 -11 -16 -4 -4 -10 13 10 15
1915 -31 0 -12 0 20 21 27 18 8 7 -27 -2
1916 -1 -14 -15 3 -3 -10 21 18 -5 -7 3 -4
1917 8 29 13 17 23 12 21 33 34 15 17 20
1918 21 22 6 17 11 -7 -13 -1 8 -4 3 -10
1919 -24 -3 -17 -3 -11 -10 -12 -5 -5 -13 -9 -12
1920 -9 -3 2 -6 -5 -16 -4 -2 0 -13 -5 -2
1921 10 11 10 -6 -5 22 -4 -8 7 13 11 2
1922 7 3 0 -6 -11 -4 -2 -2 3 7 11 9
1923 -1 6 2 -3 -5 -10 -9 -12 -20 -3 -14 0
1924 0 3 1 -18 10 6 13 16 12 0 9 -7
1925 2 3 0 1 -6 -10 -12 -17 -2 -14 -2 -8
1926 -11 -13 -8 -1 -1 -6 -3 -12 -3 -3 7 1
1927 -2 3 23 2 6 4 -3 -6 4 -3 -7 11
1928 0 13 11 11 6 -7 -2 18 12 2 9 12
1929 0 15 6 6 -6 10 11 3 4 13 8 0
1930 10 13 6 3 12 -4 -2 3 0 17 21 0
1931 15 -14 17 11 22 22 16 -10 -2 -7 -5 9
1932 -5 2 -10 -20 3 -2 -19 -5 -20 -13 -6 -5
1933 -19 -3 -14 5 10 -6 4 2 2 -4 2 5
1934 8 8 -7 1 -4 6 -1 -29 -9 7 15 -5
1935 4 -2 5 4 4 0 -2 9 -2 2 7 -2
1936 0 2 0 24 -2 -3 1 -21 -1 0 -16 -6
1937 7 0 -6 -1 9 0 -4 1 6 -4 -12 2
1938 3 -2 -4 1 5 11 17 6 11 21 -9 20
1939 19 7 7 8 1 -3 11 -15 -4 -17 -11 -1
1940 -6 -12 -10 2 -6 -11 -12 -16 -11 1 -5 -35
1941 -6 -3 -11 -2 -6 -7 -8 -14 -7 -22 -12 -4
1942 -6 -12 -3 2 -5 2 0 -2 5 1 -13 19
1943 19 4 3 10 2 -5 0 3 0 4 0 -15
1944 -9 8 8 1 5 0 -4 11 8 -9 -10 -4
1945 12 10 4 0 3 2 9 11 13 7 -2 10
1946 -6 -3 4 -2 -8 -6 -8 -2 -20 -10 0 -13
1947 1 -13 13 -4 -3 3 16 -2 14 -5 6 2
1948 3 -8 -10 -1 3 -5 -6 -14 -11 6 -7 -9
1949 -6 -7 -6 8 -6 -6 -3 -2 1 -1 -9 -8
1950 -6 12 19 2 -1 14 23 10 8 15 -6 14
1951 17 -3 -18 -10 -7 -16 -18 -6 -15 -14 -8 0
1952 -14 -11 7 0 3 8 7 -7 -3 -4 -12 -14
1953 10 -7 -9 -6 -14 -4 7 -26 -11 -1 0 -3
1954 -3 -3 -4 -10 -4 -6 -1 4 2 2 5 15
1955 9 1 -7 -12 -1 2 14 7 13 11 10 19
1956 8 6 8 1 3 2 0 3 -5 20 1 0
1957 12 -8 -4 1 -3 -3 1 -10 -6 6 -9 -4
1958 -14 -10 0 -4 -15 -10 -3 -1 -11 -16 -6 -5
1959 -21 -10 6 -1 -2 -6 -3 -6 -1 4 4 2
1960 2 -3 3 0 -3 -4 2 6 -4 -2 8 10
1961 3 11 -22 9 4 -1 3 2 3 -12 14 19
1962 23 0 3 5 7 -3 -8 13 1 7 0 -1
1963 14 19 2 -1 -2 -4 3 -10 -2 -7 1 -6
1964 1 3 7 15 -3 3 0 15 7 9 -8 -5
1965 -9 -6 -3 3 1 -1 -11 -10 -10 -2 -13 -6
1966 -14 -7 -18 -4 2 9 -3 3 -3 1 -1 -7
1967 19 17 8 9 -3 7 0 8 17 0 -7 -8
1968 -14 3 -2 0 4 11 8 -2 -3 -1 3 3
1969 -33 -17 8 4 -7 0 -6 -2 -20 -12 1 1
1970 -3 -18 -3 0 -1 5 0 -3 2 -4 15 13
1971 0 11 17 13 6 7 -3 11 14 16 4 -13
1972 2 1 -7 5 -6 -13 -21 -5 -8 0 3 -3
1973 3 -13 -3 -7 2 -1 3 5 16 4 16 24
1974 20 11 14 7 14 1 15 2 10 3 -14 -11
1975 -10 13 9 1 2 7 20 16 22 10 13 19
1976 12 14 2 6 13 -1 -8 -7 -12 -3 2 -17
1977 -13 5 -15 -13 -10 -13 -17 -12 -6 -6 -12 -14
1978 12 -31 6 -3 5 -8 -9 -7 -3 -10 2 -3
1979 -12 16 -5 -4 7 7 3 -4 -1 -2 -6 -4
1980 2 -2 -22 -13 -1 -6 -1 7 -2 -4 -4 -4
1981 -7 -12 -10 -2 6 4 1 3 4 -6 -2 9
1982 21 4 0 1 -1 -11 -15 -19 -13 -16 -27 -24
1983 -30 -35 -29 -8 14 2 2 10 17 4 6 9
1984 9 -2 -9 9 1 -5 3 -4 0 -3 6 -27
1985 5 6 -12 -2 -12 -12 2 7 -5 -10 -8 5
1986 0 -22 7 0 -2 -3 1 -21 -7 10 -18 -5
1987 -6 -20 -2 -9 -11 -20 -11 -8 -4 -5 0 -7
1988 11 -11 -6 5 11 11 15 19 19 7 16 12
1989 18 19 7 6 10 11 5 -6 6 3 -6 4
1990 3 -4 -11 2 11 -1 6 -2 0 4 -7 -3
1991 10 -1 -3 -11 -7 0 2 -2 -15 -18 0 -24
1992 -16 -10 -18 -7 2 -17 6 1 -7 -24 -6 -13
1993 -13 -20 7 -6 4 -8 -12 0 1 -11 0 -2
1994 0 -1 -4 -14 -6 -10 -16 -7 -14 -12 -3 -5
1995 -2 5 0 -15 -5 2 3 4 5 -8 0 -11
1996 11 -3 7 6 14 15 5 4 -6 -2 -6 -5
1997 18 9 -8 5 -19 -9 -2 -9 1 -3 3 -7
1998 -35 -6 -31 -14 6 8 17 14 15 7 3 9
1999 18 9 1 14 13 5 9 13 3 11 11 17
2000 15 25 13 10 10 1 -5 2 17 1 10 -12
2001 27