Japan Geoscience Union Meeting 2016

Presentation information


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

[P-EM18] Dynamics in magnetosphere and ionosphere

Wed. May 25, 2016 1:45 PM - 3:15 PM 103 (1F)

Convener:*Tomoaki Hori(Institute for Space-Earth Environmental Research, Nagoya University), Yoshimasa Tanaka(National Institute of Polar Research), 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), Shin'ya Nakano(The Institute of Statistical Mathematics), Yoshizumi Miyoshi(Institute for Space-Earth Environmental Research, Nagoya University), Chair:Tetsuo MOTOBA(Nagoya University), Yuki Obana(Department of Engineering Science, Faculty of Engineering, Osaka Electro-Communication University)

2:15 PM - 2:30 PM

[PEM18-09] Local time and seasonal dependence of occurrence rate for the zero-order mode of tweek atmospherics

*Hiroyo Ohya1, Tohru Araki, Kazuo Shiokawa2, Yoshizumi Miyoshi2, Takashi Kikuchi2 (1.Graduate School of Engineering, Chiba University, 2.Institute for Space-Earth Environmental Research, Nagoya University)

Tweek atmospherics are VLF/ELF electromagnetic waves originated from lightning discharges and propagate in the Earth-ionosphere waveguide for long distances. So far, there are few studies for the zeroth-order mode of the tweeks. The preliminary reverse impulse (PRI) electric field of the geomagnetic sudden commencement (SC) is transmitted by the TM0 mode waves propagating at the speed of light in the Earth-ionosphere waveguide (Kikuchi et al., 1978; Kikuchi and Araki, 1979). In this study, we investigate the local time and seasonal dependence of the tweek zero-order mode to understand the characteristics of the zero-order mode. For statistical analysis, we developed the automatic detection procedure for the zero-order mode. In this session, we will discuss the results for the tweek zero-order mode in detail.