Table 4 Years of Aa Type 1 and 2 cycles and their corresponding ascending and descending phases
From: New perspectives on contributing factors to the monthly behavior of the aa geomagnetic index
Type 1 | Type 2 | ||
|---|---|---|---|
Descending phase | Ascending phase | Descending phase | Ascending phase |
1872–1879 | 1879–1882 | – | 1868–1872 |
1892–1901 | 1901–1910 | 1882–1890 | 1890–1892 |
1919–1924 | 1924–1930 | 1910–1913 | 1913–1919 |
1943–1945 | 1945–1951 | 1930–1934 | 1934–1943 |
1960–1965 | 1966–1974 | 1951–1954 | 1954–1960 |
1982–1987 | 1987–1991 | 1974–1980 | 1980–1982 |
2003–2009 | 2009–2012 | 1991–1997 | 1997–2003 |
2012–2015 | |||