Abstract:
We have studied the relationship between the geomagnetic and solar activity with the method of wavelet analysis by using the 1957—2012 geomagnetic index Ap,Dst,AE and solar activity index (relative sunspot numbers R,solar radio flux F10.7) data.The results show that 11-years and 22-years cycle characteristics are in the geomagnetic index Ap,Dst,AE,and solar activity index.The peaks of Ap and AE lag behind that of solar activity index 1—2 year(s) and Dst shows an approximately inverse correlation with the solar activity index and tend to show a gradually postpone to the solar activity index in the 21st solar cycle,which indicates the postpone of geomagnetic activity under the influuence of solar activity from the 20th solar cycle.The peak of Dst has shown a tendency of decreasing,indicating its weaker reaction to solar activity.