Ionospheric Virtual Height (h′F2) Response and its Vertical Ion Drifts Characteristics at an Equatorial Station

Abstract

The Ionospheric virtual heights (h’F2) obtained from the DPS-4.2 Version of the GIRO’s site, as a computing parameter for vertical E × B ion drifts in this present study using the international quiet days (IQDs) is engaged. Vertical ion drifts () computed from virtual heights was studied over Ilorin (lat. 8.31°N, long. 4.34°E, dip lat. 2.95o) during a solar minimum (SM), a station situated at the equatorial dip. The hourly averages of vertical ion drifts, were computed from 10-international quiet days (IQDs) hourly h’F2 averages for the four seasonal months adopted. Seasonally, was having same behavourial patterns of pre-noon and post-noon peaks, but in h’F2, it had noontime, post-sunset and pre-sunrise peaks occurred in all seasons. The pre-noon peaks magnitudes are 6.8, 14.4 and 15.0 m/s in June Solsticial, Equinoctial and December Solsticial respectively; and its post-noon peaks magnitudes are 0.8, 7.4 and 7.9 m/s in December and June Solsticials, and Equinoctial seasons respectively. The h’F2 noontime peaks magnitudes are (321–410) km, post-sunset peaks magnitudes are (253–329) km and pre-sunrise peaks magnitudes are (228–318) km in all seasons. Also, depicted pre-reversal enhancement (PRE) night peaks in all seasons. The PRE peaks magnitudes are [(-4.0)–(-13.4)] m/s at 2000 LT, [(-4.9)–(-9.3)] m/s between 2200 LT and 2300 LT in all seasons. Similar phenomenal observations occurred in the h’F2 and annual patterns plots. In general, the h’F2 and magnitudes were greatest in Solsticial seasons and least in Equinoctial season. The h’F2 and stable and continual descent indicates generally that the electrons briskly drifting away from the equator triggered by solar ionization in the equatorial region. As well, seasonal peaks occurred in general are assumed to be controlled by the enhanced vertical E × B ion drifts upsurge, which adapts with former aftermaths at some stations in the West African sector during closely related solar activity