Investigation into quiet and magnetic storms periods above Magadan during October - December 2003

89-96The present work investigated the ionospheric response of the latitude above Magadan to the geomagnetic storms during October - December 2003. The study was based on storm time disturbance index, Dst, and the corresponding foF2 data above the ionosphere of Magadan in the East Asian sector. The response was investigated at all classes of storm and the quiet period inclusive. The analysis of the foF2 data during October - December 2003 shows that Dst of low magnitude can cause intense ionospheric storm. Dst values > -30 nT, which has been generally accepted to be quiet period caused major ionospheric storms of the order of 65% depletion and 59% enhancement in October. Also, two weeks before the commencement of the very intense geomagnetic storm on 20 November 2003 (Dst < -422 nT), quiet period (Dst > -30 nT) caused major ionospheric storms of the order of 70% enhancement and 45% depletion. December that was predominantly quiet, the weak Dst produced intense ionospheric storms of the order of 76% enhancement and 70% depletion. It is worthy to note that the peak positive Dst on 20 December 2003 between 06:00 and 09:00 hrs UT caused an intense ionospheric depletion above the ionosphere of Magadan with a peak value of ~70%