Low latitude ionosphere responses to solar wind forcing from GNSS data in March 2001

Abstract

We employ Global Navigation Satellite Systems (GNSS) data to investigate the low latitude ionosphere variations over the African sector (Magnetic Latitude: 0.17°) during active and quiet magnetospheric conditions during solar maximum in March 2001. The relative Total Electron Content (rTEC) index is employed to detect the variations over the threshold of |rTEC| ≥ ±30%. We observe increases in the solar wind speed, the interplanetary magnetic field (IMF), and the geomagnetic SYM-H index during the abrupt changes detected in the ionosphere. On 9March 2001, an anomalous rTEC started at 5 h UT due to a short period of southward IMF Bz orientation. At 8h UT, a minimum SYM-H of -139nT was recorded under solar wind speed of 712 km/s, causing an rTEC disturbance. Results show that solar wind forcing during the prompt electric field drives positive storm-enhanced density and observed during early morning hours.