Temporal variation of standardized indices of the 107cm solar radiant flux in winter 1.5 Strong 0.5 0.5 Weak 1960 1965 1970 975 1980 1995 2000 There are 1l years respectively for strong and weakTemporal variation of standardized indices of the 10.7cm solar radiant flux in winter Strong Weak There are 11 years respectively for strong and weak