Day-to-day variability of maximum electron density and ionospheric electron content at equatorial stations

Abstract

Comparative study of day-to-day variability of maximum electron density (<i>N</i>_m) and ionospheric Faraday electron content (<i>N</i>_F) at equatorial latitudes is presented using hourly mean values of per cent standard deviations of both the parameters. A comparison of the variability of <i>N</i>_m and <i>N</i>_F at equatorial locations Kodaikanal/Ootacamund and the equatorial anomaly peak location Ahmedabad showed higher percentage of variability in both the parameters at the peak than at the equatorial location. The magnitude of variability in <i>N</i>_F at equatorial stations Ootacamund and Huancayo is found to be significantly less than that of <i>N</i>_m regardless of the longitude of the place. The differing patterns of variability observed in <i>N</i>_m and <i>N</i>_F are attributed to the varied effect of equatorial dynamics, e.g. the varying strength of equatorial electrojet current has significant effect on maximum ionization density, while it has very little effect on the electron content at the equator.