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The annual variation of geomagnetic activity is studied through the geomagnetic indices aa, Dst and AE, according to different levels of intensity for each of the indices. For thresholds that correspond from moderate to fairly intense storms (i.e., peak aa>= 90), the distribution follows the well-known pattern of a seasonal variation, with maxima around the equinoxes and minima near the solstices...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.