JpGU-AGU Joint Meeting 2020

Presentation information

[E] Poster

P (Space and Planetary Sciences ) » P-EM Solar-Terrestrial Sciences, Space Electromagnetism & Space Environment

[P-EM13] Dynamics of Magnetosphere and Ionosphere

convener:Aoi Nakamizo(Applied Electromagnetic Research Institute, National Institute of Information and Communications Technology), Mitsunori Ozaki(Faculty of Electrical and Computer Engineering, Institute of Science and Engineering, Kanazawa University), Akiko Fujimoto(Kyushu Institute of Technology), Yuka Sato(Nippon Institute of Technology)

[PEM13-P22] Near-earth plasma environment and injection simulated by global magnetosphere model with precession of magnetic axis

*Aoi Nakamizo1, Yasubumi Kubota1, Tsutomu Nagatsuma1, Takashi Tanaka2 (1.Applied Electromagnetic Research Institute, National Institute of Information and Communications Technology, 2.Faculty of Science, Kyushu University)

Keywords:Ionospheric conductance effect, Plasma injection, Global magnetosphere simulation

The plasma distribution from the inner plasma sheet to the geosynchronous orbit is the important information not only as the plasma supply for the inner magnetosphere but also as the environment for artificial satellites. Besides, disturbances such as the plasma bubble intrusion and/or plasma injection associated with tail dynamics and substorms are superposed on the background population in that region.

Global MHD simulation is one of the powerful ways to complement observations and to know deductively what is going on in that region. However, there has been much room for improvement in our model toward the realistic simulation. In this paper, we report our recent model improvements and the performances. The improvement targeting on the magnetosphere-ionosphere coupling process is reported separately.

In order to accurately calculate the magnetic field configuration, we introduced the inclination of the magnetic axis (tilt). Besides, we introduce the precession between the magnetic axis and the rotation axis. Although the precession may appear to be less effective, it is considered to be effective because it alters the ionospheric conductance distribution, which largely modify the magnetospheric convection and dynamics (and therefore the plasma environment in the near-earth region) through the M-I coupling processes as shown by Nakamizo and Yoshikawa [2019]. Actually, background plasma distribution and intrusion from the plasma sheet are quite different between simulations with and without precession. We will show the results for equinoxes and solstices.

Nakamizo, A., & Yoshikawa, A. (2019). Deformation of ionospheric potential pattern by ionospheric Hall polarization. Journal of Geophysical Research: Space Physics, 124, 7553– 7580.