A critical analysis of monthly medians and variability of ionospheric parameters

Abstract

We made a critical study of ionospheric variability using hourly values data of different characteristics from nine ionospheric stations in the northern hemisphere for one year of high solar activity, considering: a) “typical” diurnal variation and median trend; b) ionospheric quietness; c) variability versus solar and geomagnetic activity (different indices), and d) spatial correlation. We conclude that: the variability is temporally irregular; the monthly median diurnal variation is not always statistically representative of the “typical” diurnal variation for the given month; the variability is irregularly correlated to solar activity and weakly to the Ap geomagnetic index activity; spatial correlation are quite good at distances of about 500 Km in Europe.