HR: 08:20h
AN: SA11B-02    [Abstracts]
TI: Low Latitude Ionospheric Electric Fields During Large Magnetic Storms
AU: * Fejer, B G
EM: bfejer@cc.usu.edu
AF: Center for Atmospheric and Space Sciences, Utah State University, 4405 Old Main Hill, Logan, UT 84322-4405 United States
AU: Kikuchi, T
EM: kikuchi@stelab.nagoya-u.ac.jp
AF: STELAB, Nagoya University, 3-13 Honohara, Toyokawa, 442-8507 Japan
AB: Low latitude ionospheric electric fields and currents undergo large and complex changes during periods of strong geomagnetic activity with a broad range of time scales. These electrodynamic disturbances can strongly affect the distribution of ionization over a large area of the Earth and, therefore, have been the subject of extensive recent studies. We use incoherent scatter radar vertical drift measurements from the Jicamarca Radio Observatory, and magnetic field observations to study the characteristics of equatorial ionospheric zonal electric fields during major geomagnetic storms. We focus on prompt penetration electric fields which produce large sudden and generally short lived global electrodynamic perturbations. We examine the storm-time dependence of these electric fields during different storm phases and their complex relationship to solar wind and magnetospheric parameters such as the interplanetary electric field and the cross polar cap potential. In particular, we examine the characteristics of equatorial electric and currents during periods of large southward IMF.
DE: 2441 Ionospheric storms (7949)
DE: 2712 Electric fields (2411)
DE: 2788 Magnetic storms and substorms (7954)
DE: 7949 Ionospheric storms (2441)
SC: SPA-Aeronomy [SA]
MN: Fall Meeting 2005