Japan Geoscience Union Meeting 2019

Presentation information

Print

[E] Oral

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

[P-EM09] Vertical coupling in the atmosphere and Ionosphere

Thu. May 30, 2019 9:00 AM - 10:30 AM A03 (TOKYO BAY MAKUHARI HALL)

convener:Huixin Liu(Earth and Planetary Science Division, Kyushu University SERC, Kyushu University), Loren Chang(Institute of Space Science, National Central University), Yuichi Otsuka(Institute for Space-Earth Environmental Research, Nagoya University), Chairperson:Huixin Liu(Kyushu University, Japan), Stan Solomon(National Center for Atmospheric Research, US)

9:55 AM - 10:10 AM

[PEM09-14] Spatial Fluctuation of TEC Index: A new index of ionospheric irregularities

*Guanyi Ma1, Takashi Maruyama2 (1.National Astronomical Observatories, Chinese Academy of Sciences, 2.National Institute of Information and Communications Technology )

Keywords:ionospheric irregularities, GNSS observation, SFTI

This study presents a new spatial fluctuation of total electron content (TEC) index (SFTI) to identify and analyze ionospheric irregularities. SFTI is defined as the dispersion of vertical TEC (VTEC) within a specific area at a given time. With the data from the Global Navigation Satellite System (GNSS) Earth Observation Network of Japan (GEONET), the size of the specific area for SFTI calculation can be chosen as 0.8°× 0.8° in longitude and latitude. An SFTI map generated by sliding window shows the spatial variation of the ionospheric irregularities in two dimensions. It can be used to obtain the size, shape, orientation and intensity distribution of the irregularity structures. With a series of SFTI maps, we analyzed three strong irregularity events on 12 February 2000, 20 March 2001 and 10 November 2004. The irregularities are found to consist of branching structures, which are anisotropic and elongate along longitudinal direction when first seen at low latitudes. The structures can drift and eventually move perpendicular to their orientations. It is concluded that SFTI will provide an unprecedented view of irregularity development and help to understand the process of irregularity generation.