Japan Geoscience Union Meeting 2023

Presentation information

[E] Online Poster

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

[P-EM09] Space Weather and Space Climate

Fri. May 26, 2023 10:45 AM - 12:15 PM Online Poster Zoom Room (2) (Online Poster)

convener:Ryuho Kataoka(National Institute of Polar Research), Antti A Pulkkinen(NASA Goddard Space Flight Center), Mary Aronne, Satoko Nakamura(Institute for Space-Earth Environmental Research, Nagoya University)

On-site poster schedule(2023/5/25 17:15-18:45)

10:45 AM - 12:15 PM

[PEM09-P20] Detection of Sporadic-E episode using L-band InSAR and multi-GNSS TEC

Tatsuya Fujimoto1, *Masato Furuya1, Kosuke Heki1 (1.Department of Earth and Planetary Sciences Hokkaido University)

Keywords:Sporadic-E, GNSS-TEC, InSAR

The sporadic E (Es) occurs sporadically in the E region of the ionosphere with anomalously high electron density patches. This phenomenon is known to affect the propagation of radio waves, especially in the VHF band. However, the conventional pointwise ionosonde measurements were sparsely distributed, and the detailed spatial structure of the Es remained uncertain. The dense GNSS observation network allowed to reveal the details of Es events with the use of GNSS TEC (e.g., Maeda and Heki, 2014), but even the Japanese GEONET has an average spatial separation of ~20km. Maeda et al (2016) first succeeded in observing an Es event using ALOS interferometric synthetic aperture radar (InSAR), and Furuya et al (2017) further applied the range split-spectrum method (SSM) to two Es episodes. In this study, we detected another Es episode using ALOS-2 data as well as GNSS TEC from both GEONET and the SoftBank Corp. network. We confine our investigation to daytime Es and thus examine only the ALOS-2 from descending orbits. We confirmed that L-band InSAR could provide higher spatial resolution than the multi GNSS(Global Navigation Satellite System)-TEC(Total Electron Content) method. Unlike the two cases in Furuya et al (2017), the dispersive and non-dispersive phases could be rather well-separated in the present Es episode on June 26, 2020, near Shikoku. The secondary anomaly marginally detected in GNSS-TEC could be confirmed in the InSAR data as well.

Acknowledgment: The SoftBank's GNSS observation data used in this study was provided by SoftBank Corp. and ALES Corp. through the framework of the "Consortium to utilize the SoftBank original reference sites for Earth and Space Science".