Height Variation of Drift and Pattern Parameters of Ionospheric Irregularities at Ibadan, Nigeria

摘要

The drift velocity, ratio of random changes to drift, axial ratio (elongation) and pattern sizes (N-S extent) of ionospheric irregularities are observed to vary with virtual height at the equatorial station of Ibadan (7.4°N, 3.9°E, 6°S dip ). The axial ratio and pattern size are found to reach peak values at about 270 km indicating that the N-S extent and the elongation of ionospheric irregularities peak at about the same height at which the electron density peaks. Also of note is the initial decrease of the ratio of random changes to drift in the height range of the electrojet current. The electrojet current has good correlation with drift, suggesting an increase in drift without corresponding increase in random changes of irregularities in this height range.