Inter-hemispheric comparison of ground magnetic response to interplanetary shocks: Shock impact angle versus timing and intensities of ground magnetic response
Abstract
Interplanetary (IP) shocks drive magnetosphere-ionosphere (MI) current systems that cause ground magnetic perturbations. Recent modeling and observational work have shown that IP shock impact angle is a significant factor for controlling shock-related geomagnetic activity and magnetic perturbations. Models demonstrate that highly inclined shocks drive asymmetric MI responses due to asymmetric magnetospheric compressions, while nearly head-on shocks drive nearly symmetric MI responses. In order to investigate the effects of inclined shocks on potential north-south hemisphere asymmetries in the high-latitude ground magnetic response, we use data from a recently completed chain of magnetometers on the East Antarctic Plateau, combined with magnetically conjugate stations on the west coast of Greenland. We calculate geomagnetic field perturbations (dB/dt) for each hemisphere separately. Then, we compare the time differences between the maximum dB/dt and the ratio of northern to southern hemisphere dB/dt intensities following the impact of IP shocks. We show these results according to shock impact angles obtained from a recently published database with over 500 events and discuss how shock impact angle affects north-south hemisphere asymmetries in the ground magnetic response at high latitudes.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMSM41A..04X
- Keywords:
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- 2431 Ionosphere/magnetosphere interactions;
- IONOSPHERE;
- 2475 Polar cap ionosphere;
- IONOSPHERE;
- 2704 Auroral phenomena;
- MAGNETOSPHERIC PHYSICS;
- 2776 Polar cap phenomena;
- MAGNETOSPHERIC PHYSICS