Ionospheric Conductivity and Sq Variations

A Photochemical Equilibrium Model for Ionospheric Conductivity

Diurnal changes of earthquake activity and geomagnetic Sq-variations

Statistic analyses demonstrate that the probability of earthquake occurrence in many earthquake regions strongly depends on the time of day, that is on Local Time (e.g. Conrad, 1909, 1932; Shimshoni, 1971; Duma, 1997; Duma and Vilardo, 1998). This also applies to strong earthquake activity. Moreover, recent observations reveal an involvement of the regular diurnal variations of the Earth’s magn...

The effect of nonlinear ionospheric conductivity enhancement on magnetospheric substorms

We introduce the effect of enhanced ionospheric conductivity into a low-order, physics-based nonlinear model of the nightside magnetosphere called WINDMI. The model uses solar wind and interplanetary magnetic field (IMF) parameters from the ACE satellite located at the L1 point to predict substorm growth, onset, expansion and recovery measured by the AL index roughly 50–60 min in advance. The d...

Modification of the lower ionospheric conductivity by thunderstorm electrostatic fields

This paper reports a modeling study of the modifications of the nighttime lower ionospheric conductivity by electrostatic fields produced by underlying thunderstorms. The model used combines Ohm’s law with a simplified lower ionospheric ion chemistry model to self-consistently calculate the steady state nighttime conductivity above a thunderstorm. The results indicate that although the electron...

Relationship between electric field and currents in the ionosphere and the geomagnetic Sq field

[1] Relationships of the geomagnetic Sq field to the electric field, conductivity, and currents in the ionosphere were studied from the correlation of the Sq amplitude in the Y-component with that of the ionospheric electric field and Hall currents. The electric field was obtained from the observation by the MU radar from 1989 to 2001, and the currents were estimated from the obtained field and...