On the Role of Convection in Driving Intense Geomagnetic Disturbances on the Flanks of the Magnetosphere During Magnetic Storms
Abstract
Geomagnetically induced currents (GIC) correlate with high and sustained rates of change of magnetic field measurements on the ground (dB/dt), which can be caused by various types of geomagnetic disturbances (GMD). During the geomagnetic storms of 17 March 2015 and 8 September 2017 we observed extremely similar and very large dB/dt events on the flanks that correspond to local time regions not associated with commonly considered drivers of large GMD. Comparisons to global MHD simulations indicate that the driving physics may also not be captured such that the GMD are thus not reproduced by some current MHD models. From analysing their spatio-temporal profiles in conjunction with the behaviour of the interplanetary magnetic field through various ground and space observations, including a Swarm spacecraft conjunction with ground stations, we can piece together a picture of strong convection as a driver for very large dB/dt and hence GICs in the dawn and dusk local time sectors of the magnetosphere during strong geomagnetic storms.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMGP0140007D
- Keywords:
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- 2788 Magnetic storms and substorms;
- MAGNETOSPHERIC PHYSICS;
- 4313 Extreme events;
- NATURAL HAZARDS;
- 7904 Geomagnetically induced currents;
- SPACE WEATHER;
- 7934 Impacts on technological systems;
- SPACE WEATHER