Investigating Night-time Ionospheric Currents by Swarm Magnetic Data

Abstract:

The night-side upper ionosphere is known to be populated by weak electric currents reaching their maximum intensity in the low latitude F-region, more precisely at the latitudes of the Appleton anomaly. Here, Swarm high-precision and high-resolution magnetic data are considered to investigate the features of these currents. Moreover, to gain knowledge on their origin, the correlations with the ionospheric irregularities will be investigated analyzing spread-F signatures appearing at ionospheric stations located under the crests of the equatorial ionization anomaly. Results will be then compared to those obtained by using CHAMP data for similar conditions of solar forcing, quantifying in this way the increase of information produced by Swarm constellation. Finally, implications of this study on high-resolution geomagnetic field modeling will be also discussed.