Years used for ENSO composites
Warm Events: 1877 1880 1884 1891 1896 1899 1902 1904 1911 1913 1918 1923 1925 1930 1932 1939 1951 1953 1963 1965 1969 1972 1976 1982 1986
Cold Events:1886 1889 1892 1903 1906 1908 1916 1920 1924 1928 1931 1938 1942 1949 1954 1964 1970 1973 1975 1988
Year 0 of a warm event is defined as the year when the SOI changes sign from positive to negative and when central and eastern equatorial Pacific SST anomalies become strongly positive. Year 0 of a cold event has the opposite characteristics.
From
Kiladis, G. N., and H. F. Diaz, 1989: Global climatic anomalies associated with extremes in the Southern Oscillation. J. Climate, 2, 1069-1090.