Ionospheric total electron content behavior at a pair of mid‐latitude conjugate stations

Abstract

A correlation study of the geomagnetic conjugate effects in the ionospheric total electron content was carried out between Shemya, Alaska, and Beveridge, Australia. The seasonal, diurnal, and magnetic activity dependence of the correlation was determined. It was found that for equinoxes during low magnetic activity the correlation is positive during local afternoon and negative during local night to local morning hours. For the early winter‐summer conjugate study, the correlation is generally positive during the local daytime and negative during local nighttime. For later winter‐summer the correlation is generally low, oscillating about zero throughout the day. For higher magnetic activity the correlation is generally positive throughout the day during equinoxes, dropping below zero for about 3 hours around local sunrise. A similar result holds for late winter‐summer. However, early winter‐summer only shows significant positive correlation during local afternoon hours. A study of equinoctial and winter‐summer geomagnetically conjugate storm effects shows that while equinoctial storm effects can occur simultaneously in both hemispheres, the seasonal differences between winter and summer storms tend to dominate during solstice storms. Local winter nighttime variations in total electron content appear to occur simultaneously in the summer hemisphere at the magnetically conjugate station for high levels of magnetic activity, but not for low levels of magnetic activity.