The years of ENSO and IOD based on the Ummenhofer et al. (2009) classification
| . | Negative IOD . | Neutral IOD . | Positive IOD . |
|---|---|---|---|
| El Niño | 1930 | 1877, 1888, 1899, 1905, 1911, 1914, 1918, 1925, 1940, 1941, 1965, 1972, 1986, 1987 | 1896, 1902, 1957,1963, 1982, 1991, 1997, 2009 |
| Neutral ENSO | 1915, 1958, 1968, 1974, 1980, 1985, 1989, 1992 | 1880, 1881, 1882, 1883, 1884, 1895, 1898, 1900, 1901, 1904, 1907, 1908, 1912, 1920, 1921, 1927, 1929, 1931, 1932, 1934, 1936, 1937, 1939, 1943, 1947, 1948, 1951, 1952, 1953, 1953, 1959, 1960, 1962, 1966, 1967, 1969, 1971, 1976, 1977, 1979, 1983, 1990, 1993, 1995, 2001, 2002, 2003, 2005, 2006 | 1885, 1887, 1891, 1894, 1913, 1919, 1923, 1926, 1935, 1944, 1945, 1946, 1961, 1994, 2004, 2008 |
| La Niña | 1906, 1909, 1916, 1917, 1933, 1942, 1975 | 1878, 1879, 1886, 1889, 1890, 1892, 1893, 1897, 1903, 1910, 1922, 1924, 1928, 1938, 1949, 1950, 1954, 1955, 1956, 1964, 1970, 1973, 1978, 1981, 1984, 1988, 1996, 1998, 2000 | 1999, 2007 |
| . | Negative IOD . | Neutral IOD . | Positive IOD . |
|---|---|---|---|
| El Niño | 1930 | 1877, 1888, 1899, 1905, 1911, 1914, 1918, 1925, 1940, 1941, 1965, 1972, 1986, 1987 | 1896, 1902, 1957,1963, 1982, 1991, 1997, 2009 |
| Neutral ENSO | 1915, 1958, 1968, 1974, 1980, 1985, 1989, 1992 | 1880, 1881, 1882, 1883, 1884, 1895, 1898, 1900, 1901, 1904, 1907, 1908, 1912, 1920, 1921, 1927, 1929, 1931, 1932, 1934, 1936, 1937, 1939, 1943, 1947, 1948, 1951, 1952, 1953, 1953, 1959, 1960, 1962, 1966, 1967, 1969, 1971, 1976, 1977, 1979, 1983, 1990, 1993, 1995, 2001, 2002, 2003, 2005, 2006 | 1885, 1887, 1891, 1894, 1913, 1919, 1923, 1926, 1935, 1944, 1945, 1946, 1961, 1994, 2004, 2008 |
| La Niña | 1906, 1909, 1916, 1917, 1933, 1942, 1975 | 1878, 1879, 1886, 1889, 1890, 1892, 1893, 1897, 1903, 1910, 1922, 1924, 1928, 1938, 1949, 1950, 1954, 1955, 1956, 1964, 1970, 1973, 1978, 1981, 1984, 1988, 1996, 1998, 2000 | 1999, 2007 |