← Back to Sessions

Satellite and Ground Based Measured Ionospheric Variations Over Seismic Active Areas

Session: Application of Remote Sensing and Space-Based Earth Observations Data in Earthquake Research I

Type: Oral

Date: 4/21/2021

Presentation Time: 05:45 PM Pacific

Description: 

In this study we investigate ionospheric disturbances over earthquake prone areas with two methods.

The satellite based approach - in our case magnetic field measurements from CSES-01 and Swarm mission - shed light on ionospheric F-region plasma variations at low-earth orbit (LEO) altitudes around 500 km. The complementary second technique is based on variations of the so-called Earth-ionosphere waveguide, the cavity between Earth's surface and the lower ionospheric D/E (day/night) upper boundary at approx. 70-90 km altitude. Electric field amplitude and phase perturbations of paths between several narrowband VLF/LF transmitter and a receiver network are continuously recorded.

In both cases the lithosphere-atmosphere-ionosphere coupling (LAIC) is a key area and of vital importance in order to establish the propagation characteristics from the seismic zone up to high altitudes. Possible mechanisms are discussed in the literature, e.g. [1], [2]. In this presentation we focus on acoustic waves and atmospheric gravity waves (AGW) as energy-momentum transport channel (and filter) to connect the different regions from bottom to top.

We examine events form the United States Geological Survey (USGS) earthquake catalog, assign a spatial box of a few degrees in latitude and longitude around the epicenter, investigate measurements from satellite- and/or VLF/LF paths which crosses the box, and report on differences in variations prior and after the events.

These findings could point to regular automated procedures in order to disentangle seismic from nonseismic ionospheric pattern and are equally important for upcoming satellite missions and extended ground based networks.

References: [1] Molchanov, O. A. and Hayakawa, M., “Seismo-electromagnetics and related phenomena. History and latest results.”, 189 p., Terrapub, 2008. ISBN 978-4-88704-143-1 [2] Ouzounov, D., Pulinets, S., Hattori, K. and Taylor P., “Pre-Earthquake Processes: A Multidisciplinary Approach to Earthquake Prediction Studies”, 384 p., Geophysical Monograph Series, 2018. ISBN: 978- 1-119-15693-2

Presenting Author: Christoph Schirninger

Student Presenter: No

Authors