During geomagnetic storms and substorms, the magnetosphere and ionosphere are strongly coupled by precipitating magnetospheric electrons from the Earth's plasma sheet and driven by both magnetospheric and ionospheric processes. Magnetospheric wave activity initiates electron precipitation, and the ionosphere and upper atmosphere further facilitate this process by enhancing the value of precipitated energy fluxes via connection of two magnetically conjugate regions and multiple atmospheric reflections. This paper focuses on the resulting electron energy fluxes and affiliated height‐integrated Pedersen and Hall conductances in the auroral regions produced by multiple atmospheric reflections during the 17 March 2013 geomagnetic storm and their effects on the inner magnetospheric electric field and ring current. Our study is based on the magnetically and electrically self‐consistent Rice Convection Model‐Equilibrium of the inner magnetosphere with SuperThermal Electron Transport modified electron energy fluxes that take into account the electron energy interplay between the two magnetically conjugate ionospheres. SuperThermal Electron Transport‐modified energy flux in the Rice Convection Model‐Equilibrium leads to a significant difference in the global conductance pattern, ionospheric electric field formation, Birkeland current structure, ring current energization and its energy content, subauroral polarization drifts intensifications and their spatial locations, interchange instability redistribution, and overall energy interplay on the global scale.
Charged particles are observed to be injected into the inner magnetosphere from the plasma sheet and energized up to high energies over short distance and time, during both geomagnetic storms and substorms. Numerous studies suggest that it is the short‐duration and high‐speed plasma flows, which are closely associated with the global effects of magnetic reconnection and inductive effects, rather than the slow and steady convection that control the earthward transport of plasma and magnetic flux from the magnetotail, especially during geomagnetic activities. In order to include the effect of the inductive electric field produced by the temporal change of magnetic field on the dynamics of ring current, we implemented both theoretical and numerical modifications to an inner magnetosphere kinetic model—Hot Electron‐Ion Drift Integrator. New drift terms associated with the inductive electric field are incorporated into the calculation of bounce‐averaged coefficients for the distribution function, and their numerical implementations and the associated effects on total drift and energization rate are discussed. Numerical simulations show that the local particle drifts are significantly altered by the presence of inductive electric fields, in addition to the changing magnetic gradient‐curvature drift due to the distortion of magnetic field, and at certain locations, the inductive drift dominates both the potential and the magnetic gradient‐curvature drift. The presence of a self‐consistent inductive electric field alters the overall particle trajectories, energization, and pitch angle, resulting in significant changes in the topology and the strength of the ring current.
more » « less- NSF-PAR ID:
- 10375440
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Space Physics
- Volume:
- 126
- Issue:
- 3
- ISSN:
- 2169-9380
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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