Global-SST ENSO index

JISAO data Global-SST ENSO index
This index is experimental. Until further notice, you should use the eastern equatorial Pacific SST index as an ENSO index.
This ENSO index is taken as the average SST equatorward of 20-degrees latitude (north and south) minus the average SST poleward of 20-degrees. Anomalies are with respect to the period 1950-79. The number of observations contributing is at least 1000 in each month and year beginning in 1860.
The time series has been smoothed with successive 11- and 9-point running means for this plot.
The time series (degrees C) is available in both ASCII and MATLAB formats:
ASCII: time series and number of observations files.
MATLAB: time series and number of observations files.
Digital values:
The anomalies are in hundredths of a degree Celcius, with missing values left blank.
       jan  feb  mar  apr  may  jun  jul  aug  sep  oct  nov  dec
 1854  -22           -161    8   24   30  -14   -5   -5   41   18
 1855  -21  -29    1   39  -25   28   -2    1   -6   18  -18   15
 1856  -16    2  -16  -25   -3   35   -9   13   27   40   -6   27
 1857   20   -8  -44  -12  -41   18  -24   -1    8   25  -18   -2
 1858  -18  -38    3  -38   -5   -4   -8   27   72   43   33   -7
 1859  -22   26    9    9   50   29   -4   32  -18    3  -46  -27
 1860  -40    1  -16   28   -9  -32  -19    0   -2   18  -17   -9
 1861  -12    0   20  -27  -26  -14   16   10   -9    7   14   13
 1862   14   -9    9   17   38   40   19   68   32   37    6   20
 1863  -17   13  -19  -27   -6   31  -23   -1   19   29   -4  -10
 1864  -32  -53  -24  -23  -29  -16   10    5   18  -36   26  -16
 1865  -18   26    9   31   27   42  -16   56   36  -13   31    7
 1866   12   10   27   41    2    4  -19   37   13  -10   29  -25
 1867  -10   28   15   14   35    9    7   51  -21   27    7   31
 1868   53   48   28    7   21   11  -11   17   44   30   35   -9
 1869  -31   -9    9   15    1   -8  -16   81   35   15    9   43
 1870    3   38   -8  -41  -25   15   15  -19   15   19  -41   15
 1871  -32    7   10  -18   -8    3   16    6   32   30    0   10
 1872  -35   37  -22  -27   -8    3  -21   11   16   10  -23   -5
 1873   -5   -5   14   12  -12  -11  -25   30   49   11   16   30
 1874  -38   -7   -2  -68   -1   13  -10   -8   45    5   -7   21
 1875   23   31   -3  -60  -48  -20   24  -49    0   43   36   62
 1876   35   12   62   33   17   20    0   16    1   -2   16   36
 1877   13   -5  -17   14   26   18   39   68   52   58   15   33
 1878   43   42   36   53   32   48   28   34   15   40   29   20
 1879  -13   35   -4    1  -22    6   -8    1   -4    6   27   39
 1880   36   31   12  -31  -12    3  -54  -18  -15  -19  -14   25
 1881    4   26   25   15   18   -2   12    9   21   27   30   21
 1882   17   -1    3   19  -19  -41  -29   23   35   16    1    9
 1883   15  -15    6  -18   15   -9   -4  -13   29   14  -21   -9
 1884  -30  -12  -25  -18  -12   18   17    8   29   23    6   14
 1885   39   17   -4   -4   15  -24  -21  -16   39   21   17   26
 1886   13   23   45   -1   -6  -10  -19   10   14   12   21   -5
 1887   -2   21   -7  -27  -23  -62  -57  -40   -3   -6   22   20
 1888   29   14   38   13   -8  -36  -23    1    6   26   22   16
 1889    8   19   39   40    0  -17   23   10   20   23    4   -5
 1890  -13  -23  -12  -24  -42  -53  -41  -49  -38  -22  -20   -9
 1891  -13   -5   -6   -6  -12   -5  -28   -3    4   17   32    8
 1892   14   14    9  -21  -26  -31  -47  -39  -13   -1  -25   18
 1893    6  -27  -19  -34  -47  -62  -28   -4  -11  -10  -12  -10
 1894  -29  -13  -20  -28  -25  -21  -26  -32  -18    5   -1    2
 1895   31   31   33   17  -24  -38  -17    8   10   24   45   34
 1896   39   20   20   20  -18  -10  -14   -5   14   26   53   45
 1897   49   31   22   23   12  -11   15   28   42   44   38   22
 1898  -17  -26  -24  -39  -39  -72  -72  -67  -54  -14   16    9
 1899  -13   14  -19  -40  -36  -24  -46  -30  -29  -22   -5   21
 1900   14    6   13   -8   -8  -11    1  -14   -6   -6   15   35
 1901   32   17   18   27   -2  -19  -22    5   10   19   24   24
 1902   -6   11   -8   -3  -12   12   12   15    3    2   -8   19
 1903   16   -4  -16  -15   -1    1    4   19   15   16  -18   -9
 1904  -18  -35  -23  -51  -47  -43  -56  -38   -1  -23  -20   -4
 1905   -2    6   -9  -52  -28  -16  -60   -2   25   47   47   27
 1906   10   38   29    0   -1  -30  -23  -32  -15  -27  -13   25
 1907   24   38  -14  -17  -23   -6   15    4  -18    7    6   -5
 1908    3   -7  -13  -13  -51  -68  -51  -23    6  -30  -28  -16
 1909  -11    2   13  -16  -23    1   17    1    6  -25    4   18
 1910    1    1   -1  -35  -24  -24   12    1   -1  -15    5   -9
 1911    0  -11  -10  -21  -36  -35  -42  -69  -59   -9   -2   -5
 1912   19    9  -21   -5  -28   12    6   54   77   47   29   -1
 1913  -21  -11  -18  -29  -20   -1   12   11   -1  -18  -20    4
 1914   21    9  -12  -30  -34   -7  -21    5   10   30   46   60
 1915   35   30   25   24   -9  -16   14    0   12   30   39   35
 1916   21   11   27    3  -26  -17    6   -2  -15  -11    9  -11
 1917   15   42   18   15   14   -8    9   -6  -18  -11   -4   13
 1918   30  -13    2  -57  -64  -44   -4  -21   26   47   52   57
 1919   29   64   53   14   22  -29   22   -5   13    5   39   54
 1920   41   30    6  -52  -51  -29  -43  -18   -4  -13   18   24
 1921   14   -8  -20  -19  -54  -29  -40   -6  -17  -26    5   14
 1922   20   18   -3  -18  -32  -42  -12  -14   -2   14   17   23
 1923   13    2  -15  -27  -22   13   -7  -24    4   29   29   53
 1924   56   63   50   34   -5  -19    4   14   11    6   11    3
 1925  -20  -38  -27   -9   -6  -10   21    4   20   15   21   25
 1926   26   19   31    3   12   37   29   23   -2   -5    8   36
 1927   15   31    1  -12  -49  -28  -19  -14   21   18    7   37
 1928   38   21   14  -18   -1    0  -31  -29  -31   -9   13   26
 1929   31   40   25   10  -14  -17   -9  -13  -35    0    7   10
 1930    0   18   -5  -18  -37  -62  -52   -4   -8   15   28   20
 1931   29   53   56   34   23   -7   21   10   17   17   22   22
 1932   -4   28   13    2   -3  -15  -43  -51  -49  -13    0    7
 1933   66   77   63   27   -1  -36  -42  -34  -23   -3   41   44
 1934   74   61   32   20  -25  -33  -37   13    6   27   47   23
 1935   58   49   28   11    5  -11  -23  -16    2   17   39   63
 1936   78   85   76   40   28  -13  -14    4   -6   30   31   55
 1937   58   57   52   26    2  -19  -37  -42  -13   -2   18   50
 1938   52   62   23  -12  -22  -54  -35  -37  -13  -16   -8    1
 1939   19   -2   -1  -15  -15  -18  -26  -40  -46   -8   46   80
 1940   88  107  102   89   44    0  -11   25   40   50   77   79
 1941  100  111  104  100   40   30   39   89   65  103   91  144
 1942  125   93   43   41   12   -7  -31  -17  -10   -5    4   60
 1943   54   44   -7  -10  -24  -42  -16   -3    1   16   15    9
 1944   -7   -4   10    2  -20   -8   18    9   17    1   22   40
 1945   32   40   12   -8   26   17   19   30    9   -1   22    6
 1946   25   31   16   23  -24   -9  -27   -3   -9  -15  -16   21
 1947   26   25   22  -20   -5   12    8   -5  -32  -23  -31    2
 1948    6   10    7   -9  -23  -12    6  -19  -15  -15  -34    2
 1949  -29  -20  -26  -37  -44  -25  -16  -19  -33  -39  -57  -38
 1950  -28  -29  -24  -29  -39  -52  -52  -44  -37  -37  -42  -40
 1951  -56  -57  -47  -30  -21  -25  -25  -23   -5    7    7   -8
 1952  -24  -14   -5   -1   -2  -36  -39  -52   -8  -21  -15    0
 1953    4   -3   -7   -7  -22   -2   -6    3   -7   -4  -14  -15
 1954  -14   -9  -13  -30  -19  -15   -9   -4  -16  -36  -33  -41
 1955  -26  -33  -35  -46  -48  -38  -48  -26  -28  -39  -43  -42
 1956  -30  -24  -13   -7  -40  -28  -32  -23  -21  -25  -26  -24
 1957  -44  -36  -15  -22    1    5   -9   -1   -4    3   13   19
 1958   27   41   37   34   14    8   11   -2   -7  -12  -30  -15
 1959   -5    3   -4    1   -5   13   -7  -19  -28  -18  -15   -5
 1960    4    4   21    6    3  -21  -13   -8  -18  -24  -11    5
 1961    8   11   -7   -7  -17  -30  -41  -33  -34  -31  -26  -19
 1962  -21  -43  -25  -20   -1   -4   -8  -10  -23  -14  -14  -23
 1963  -22  -23  -21  -13    5  -11    2   17   15   14   29   30
 1964   40   34   16   -2  -18  -13    8    7    0    2  -13  -28
 1965  -31   -8   -2   14   19    8   13   26   40   28   38   39
 1966   47   61   46   52   26   33   45   35   21   15   31   33
 1967    8  -11  -23   -2    6    0  -13  -44  -26  -28  -34  -20
 1968  -23  -23  -22  -31  -20    7   33   26   15   19   18   37
 1969   45   38   60   50   58   55   27   16   20   39   36   33
 1970   48   48   57   42   36   28   30    5    7   -1   -7   13
 1971   16    5   -3   -7   -9   -7  -20    3   14  -17  -10  -20
 1972   -5    7  -17   -8   10   22   15   39   43   76   69   46
 1973   52   51   38   27   29   20   27   25   17   10    8    5
 1974  -24  -21  -27  -21   -5    6   23   19    5   17   11    1
 1975  -12  -12   -7   -1  -10    6   11   -7   -5   -2  -10   -9
 1976  -11  -15  -20  -13  -10   -6    5   18   28   36   54   26
 1977   32   12    1    8   16   31   20   29   11   21   19   15
 1978   27   22   30   30   25   17   19   12    6    4   -2   -6
 1979   18   25   32   31   37   32   30   16   25   15   13   12
 1980   19   12    9   15   38   25   28   24   33   41   37   36
 1981   30   25   33   27   28   14   30   15   30   52   38   37
 1982   27   15   10    7   14   27   35   46   43   41   43   56
 1983   42   53   47   37   30   53   47   42   38   36   24   29
 1984   29   31   52   44   34   27   29   -2   27   29   22   12
 1985   18   24    9   -4   -5    4   17   34   22   19   26   27
 1986    4   24   12   28   21   30   49   34   41   38   45   26
 1987   36   34   48   41   56   64   56   74   68   85   82   69
 1988   50   57   59   42   38   26   28   32   49   28   29   10
 1989   -1  -11  -25  -27  -20   -8   10   -3    4   24   24   21
 1990    3    3   -5   -7    4    5    8    0    2   16   24   21
 1991   21   19   17    6   30   25   30   24   19   32   39   38
 1992   20   18    1   19   15   15   30   38   36   42   26   15
 1993    5    4   20   26   24   40   43   27   38   52   55   53
 1994   35   33   24    4    5    9  -23  -15   12   32   20   23
 1995   34   17    7    0    2    2  -14  -21    3   -2   14   29
March 2000
Todd Mitchell (mitchell@atmos.washington.edu)
JISAO data