Interhemispheric Observations of Geomagnetic Pulsations Associated with Foreshock Transient Events

We report on interhemispheric observations of geomagnetic pulsations and ionospheric convection in association with solar wind transient phenomena. The interaction between the solar wind and the magnetosphere induces a variety of geospace responses including electric currents and geomagnetic pulsations. Single-hemispheric observations, however, do not provide sufficient information on solar wind-magnetosphere-ionosphere coupling processes and energy transport to the geospace system. To address this issue, the present study focuses primarily on interhemispherically asymmetric features in the magnetosphere-ionosphere coupling processes associated with foreshock transient events by utilizing a ground instrument network at magnetically conjugate locations in both hemispheres. We investigate possible external drivers that affect asymmetries (e.g., IMF orientation, solar irradiance, geomagnetic activity, ionospheric conductivity, etc.). The spatiotemporal and spectral differences between the Interhemispheric responses are also reported.