On the response of the equatorial and low latitude ionospheric regions in the Indian sector to the large magnetic disturbance of 29 October 2003

摘要

The present paper investigates the response of the equatorial and lowlatitude ionosphere over the Indian longitudes to the events on 29 October2003 using ionosonde data at Trivandrum (8.5° N (0.5° N geomagnetic),77° E) and SHAR (13.7° N (5.7° N geomagnetic), 80.2° E),ground-based magnetometer data from Trivandrum and Total Electron Content(TEC) derived from GPS data at the locations of Ahmedabad (23° N (15° Ngeomagnetic), 72° E), Jodhpur (26.3° N (18.3° N geomagnetic),73° E) and Delhi (28° N (20° N geomagnetic), 77° E). Followingthe storm sudden commencement, the TEC at all the three stations showed anoverall enhancement in association with episodes of inter-planetary electricfield penetration. Interestingly, real ionospheric height profiles derivedusing the ionosonde data at both Trivandrum and SHAR showed significantshort-term excursions and recoveries. In the post noon sector, thesefeatures are more pronounced over SHAR, an off equatorial station, thanthose over Trivandrum indicating the increased effects of neutral winds.