4:45 PM - 5:00 PM
[MIS09-18] The synergistic phenomenon of pre-earthquake signals in the atmosphere and ionosphere.
Potential geospace impacts related to M6+ earthquakes in Kyushu, Japan.
Keywords:pre-earthquake, geospace, atmosphere, ionosphere, LAIC
We present a multi-parameter study of transient phenomena observed in the Earth's atmosphere-ionosphere environment. These phenomena are plausibly associated with the three most recent major earthquakes in Japan: M 7.0 on April 15, 2016, in Kumamoto; M 7.1 on August 8, 2024, in the Hyuganada Sea; and M 6.8 on January 13, 2025, located 12 km ESE of Miyazaki. All earthquakes occurred in close proximity along the coast of Kyushu Prefecture.
We collected outgoing long-wavelength radiation (OLR) from NPOESS. Atmospheric chemical potential (ACP) was sourced from NASA assimilation models, and variations in electron density in the ionosphere were obtained through GPS Total Electron Content (GPS/TEC) and F2 critical frequency from ionosondes. Furthermore, we examined how significant seismic activity responds to geomagnetic storms through a joint analysis of solar wind, the geomagnetic field, and earthquake catalogs. We focused on the periods of geomagnetic storms preceding the M7 Kumamoto, M7.1 Hyuganada Sea, and M6.8 Miyazaki events, which met the following criteria [Ouzounov and Khachikyan, 2024]: the high-latitude area of the longitudinal region where an earthquake occurred was located under the polar cusp at the time of the magnetic storm's onset.
We conducted an OLR analysis for all three earthquakes from 2004 to 2025, revealing an unusual pattern at a ±2 sigma confidence level co-located with the epicenter. The first sign of a transient atmospheric anomaly was detected 1 to 2 months before the main shocks. We observed a similar rapid radiation enhancement for all events, which may be connected to an anomalous latent heat flux in the region experiencing increased tectonic activity. We examined ACP variations (every 3 hours) using data from the GEOS assimilation model. The persistence of OLR and ACP anomalies suggests processes of rapid thermal field buildup on the ground, coinciding with other atmospheric changes such as temperature and humidity.
Our integrated data search reveals reoccurring abnormal patterns within the Dobrovolsky-Bowman estimating zone for earthquake preparation associated with the three major events. We also observed a synergistic “rhythm” like abnormal phenomena from satellite OLR data, ACP, and GPS/TEC beginning one to two months before the M7 Kumamoto, M7.1 Hyuganada Sea, and M6.8 Miyazaki events. By incorporating near-space and ground data grounded in the physical concept of Lithosphere-Atmosphere-Ionosphere Coupling (LAIC), we demonstrate the ability to identify, at a regional level, the reocurring patterns of pre-earthquake signals in the atmosphere-ionosphere environment linked to significant seismic events (M6+).
We collected outgoing long-wavelength radiation (OLR) from NPOESS. Atmospheric chemical potential (ACP) was sourced from NASA assimilation models, and variations in electron density in the ionosphere were obtained through GPS Total Electron Content (GPS/TEC) and F2 critical frequency from ionosondes. Furthermore, we examined how significant seismic activity responds to geomagnetic storms through a joint analysis of solar wind, the geomagnetic field, and earthquake catalogs. We focused on the periods of geomagnetic storms preceding the M7 Kumamoto, M7.1 Hyuganada Sea, and M6.8 Miyazaki events, which met the following criteria [Ouzounov and Khachikyan, 2024]: the high-latitude area of the longitudinal region where an earthquake occurred was located under the polar cusp at the time of the magnetic storm's onset.
We conducted an OLR analysis for all three earthquakes from 2004 to 2025, revealing an unusual pattern at a ±2 sigma confidence level co-located with the epicenter. The first sign of a transient atmospheric anomaly was detected 1 to 2 months before the main shocks. We observed a similar rapid radiation enhancement for all events, which may be connected to an anomalous latent heat flux in the region experiencing increased tectonic activity. We examined ACP variations (every 3 hours) using data from the GEOS assimilation model. The persistence of OLR and ACP anomalies suggests processes of rapid thermal field buildup on the ground, coinciding with other atmospheric changes such as temperature and humidity.
Our integrated data search reveals reoccurring abnormal patterns within the Dobrovolsky-Bowman estimating zone for earthquake preparation associated with the three major events. We also observed a synergistic “rhythm” like abnormal phenomena from satellite OLR data, ACP, and GPS/TEC beginning one to two months before the M7 Kumamoto, M7.1 Hyuganada Sea, and M6.8 Miyazaki events. By incorporating near-space and ground data grounded in the physical concept of Lithosphere-Atmosphere-Ionosphere Coupling (LAIC), we demonstrate the ability to identify, at a regional level, the reocurring patterns of pre-earthquake signals in the atmosphere-ionosphere environment linked to significant seismic events (M6+).