2:15 PM - 2:30 PM
[PEM15-13] Three-dimensional structure of ionospheric global current system driven by M-I coupling
Keywords:ionospheric simulation, potential solver, Magnetosphere-Ionosphere coupling
There exists global current system in the ionosphere due to Magnetosphere-Ionosphere coupling. However, we do not know the three-dimensional structure of it especially the path of current, which means where the current goes to and comes from.
There are few previous studies to investigate global three-dimensional current in ionosphere. Takeda [1982] calculated the current system produced by field-aligned current under the quiet condition with numerical simulation. It showed three-dimensional distribution, but did not show the path.
The purpose of this study is to reveal the three-dimensional global continuity of ionospheric current system triggered by Region-1 FAC.
We calculate the current system with electrodynamics component of GAIA [Jin et ai., 2011]. The result shows two-cell convection pattern in high latitude. Equatorial electrojet can also be seen, but streamlines of current are flowing two different altitudes. This indicate that EEJ is formed by Cowling effect in M-I coupled situation.
For more analysis, we separate electric field and current in two parts as explained in Yoshikawa et al. [2013]. One is a component in the case of no Hall conductivity (called primary component), the other is additional component of existence of Hall conductivity (called secondary component). Then we find primary current system is symmetry of dawn-dusk in dayside, but secondary one is not. Also, secondary current has FAC which is different from the current structure explained in Kikuchi et al. [1996].
There are few previous studies to investigate global three-dimensional current in ionosphere. Takeda [1982] calculated the current system produced by field-aligned current under the quiet condition with numerical simulation. It showed three-dimensional distribution, but did not show the path.
The purpose of this study is to reveal the three-dimensional global continuity of ionospheric current system triggered by Region-1 FAC.
We calculate the current system with electrodynamics component of GAIA [Jin et ai., 2011]. The result shows two-cell convection pattern in high latitude. Equatorial electrojet can also be seen, but streamlines of current are flowing two different altitudes. This indicate that EEJ is formed by Cowling effect in M-I coupled situation.
For more analysis, we separate electric field and current in two parts as explained in Yoshikawa et al. [2013]. One is a component in the case of no Hall conductivity (called primary component), the other is additional component of existence of Hall conductivity (called secondary component). Then we find primary current system is symmetry of dawn-dusk in dayside, but secondary one is not. Also, secondary current has FAC which is different from the current structure explained in Kikuchi et al. [1996].