Magnetic activity dependence of the electric drift below L=3

Author
Keywords
Abstract
More than two years of magnetic and electric field measurements by the Van Allen Probes are analyzed with the objective of determining the average effects of magnetic activity on the electric drift below L=3. The study finds that an increase in magnetospheric convection leads to a decrease in the magnitude of the azimuthal component of the electric drift, especially in the night-side. The amplitude of the slowdown is a function of L, local time MLT, and Kp, in a pattern consistent with the storm-time dynamics of the ionosphere and thermosphere. To a lesser extent, magnetic activity also alters the average radial component of the electric drift below L=3. A global picture for the average variations of the electric drift with Kp is provided as a function of L and MLT. It is the first time that the signature of the ionospheric disturbance dynamo is observed in near-equatorial electric drift measurements.
Year of Publication
2018
Journal
Geophysical Research Letters
Date Published
04/2018
URL
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2018GL077873
DOI
10.1029/2018GL077873