Japan Geoscience Union Meeting 2025

Presentation information

[E] Oral

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

[P-EM10] Space Weather and Space Climate

Tue. May 27, 2025 1:45 PM - 3:15 PM 302 (International Conference Hall, Makuhari Messe)

convener:Ryuho Kataoka(National Institute of Polar Research), Antti Pulkkinen(NASA Goddard Space Flight Center), Mary Aronne(NASA GSFC/CUA), Yumi Bamba(National Institute of Information and Communications Technology), Chairperson:Mary Aronne(NASA GSFC/CUA), Antti Pulkkinen(NASA Goddard Space Flight Center)

2:00 PM - 2:15 PM

[PEM10-14] Radiative Magnetohydrodynamic Modeling of the Solar Wind and Interplanetary Magnetic Field Incorporating Small-Scale Interchange Reconnection

★Invited Papers

*Haruhisa Iijima1, Takuma Matsumoto1, Hideyuki Hotta1, Daikou Shiota2, Shinsuke Imada3 (1.Nagoya University, 2.National Institute of Information and Communications Technology, 3.The University of Tokyo)

Keywords:Solar Corona, Solar Wind, Interplanetary Magnetic Field

The prediction of the ambient solar wind and interplanetary magnetic field (IMF) has long been a critical task in space weather research. Corotating interaction regions (CIRs) formed by solar wind interactions are one of the primary sources of geomagnetic disturbances. In addition to triggering geomagnetic effects, the IMF guides high-energy charged particles accelerated in space toward Earth.

Recent observations from missions such as the Solar Orbiter and the Parker Solar Probe have significantly clarified the physical connection between the Sun and the interplanetary space environment. In particular, small-scale transients and interchange magnetic reconnection observed on the solar surface have emerged as key factors in the solar wind formation process. However, the long-range coupling between the solar surface and the interplanetary space has posed challenges for constructing a realistic model of the magnetically open solar atmosphere.

We have recently conducted large-scale radiative magnetohydrodynamic (MHD) simulations to elucidate the origin of the solar wind and the IMF. Our simulations extend from the upper convection zone to the magnetically open corona, including the solar wind acceleration region. This self-consistent model captures the spontaneous formation of thermal convection, dynamo action, and MHD wave excitation, successfully reproducing realistic supergranular-scale interchange reconnection. With minimal empirical assumptions, our model heats the corona to million-degree temperatures and accelerates a supersonic solar wind. In this talk, we will present our latest progress in ab initio modeling of the interplanetary space environment and discuss its potential applications in numerical space weather prediction.