日本地球惑星科学連合2021年大会

講演情報

[E] 口頭発表

セッション記号 P (宇宙惑星科学) » P-EM 太陽地球系科学・宇宙電磁気学・宇宙環境

[P-EM08] 宇宙天気・宇宙気候

2021年6月4日(金) 15:30 〜 17:00 Ch.06 (Zoom会場06)

コンビーナ:片岡 龍峰(国立極地研究所)、A Antti Pulkkinen(NASA Goddard Space Flight Center)、草野 完也(名古屋大学宇宙地球環境研究所)、坂口 歌織(情報通信研究機構)、座長:Antti A Pulkkinen(NASA Goddard Space Flight Center)、片岡 龍峰(国立極地研究所)

16:45 〜 17:00

[PEM08-12] Correct reproduction of solar differential rotation in high-resolution simulation with Fugaku

★Invited Papers

*堀田 英之1、草野 完也2 (1.千葉大学大学院理学研究科、2.名古屋大学宇宙地球環境研究所)

キーワード:太陽、対流層、磁場

We carry out high-resolution simulations in supercomputer Fugaku to understand the generation mechanism of the solar differential rotation.
The sun is rotating differentially with the slow pole and the fast equator. While the observation for the solar differential rotation has a long history from the 1600s, we still do not understand the maintenance mechanism of the solar differential rotation. The anisotropic turbulence in the solar convection zone is thought to generate the differential rotation. Recent high-resolution simulations fall into the anti-solar differential rotation regime, i.e., the fast pole and the slow equator. The reason why we cannot reproduce the solar differential rotation is that the numerical simulation tends to show fast convection.
In order to deal with this problem, we carry unprecedentedly high-resolution simulations with supercomputer Fugaku. We optimize our R2D2 code especially for Fugaku to obtain the best performance in the supercomputer. Using the optimized code, we carry out the high-resolution simulation with more than 5 billion grid points and we for the first time reproduce the solar differential rotation without using any artificial technique. In the simulation, the magnetic field becomes unexpectedly strong and suppresses the convection. As a result, the convection generates the solar differential rotation correctly. The new simulation totally changes our view of the solar convection zone.