Academic News
A multinational research team from Japan, China, and Taiwan—featuring Professor Jann-Yenq Liu of the Center for Astronautical Physics and Engineering at National Central University (NCU)—has successfully reconstructed the full three-dimensional evolution of ionospheric disturbances following the 2011 Great East Japan Earthquake. This breakthrough overcomes the long-standing limitations of two-dimensional analyses based on Global Navigation Satellite System (GNSS) Total Electron Content (TEC) data, providing the first comprehensive 3D visualization of multiple atmospheric wave structures triggered by earthquakes and tsunamis. The findings were published in the international journal Scientific Reports.
The study was led by Professor Katsumi Hattori of the Graduate School of Science at Chiba University, in collaboration with the China Earthquake Administration and National Central University. By transcending conventional observation techniques, the research allows co-seismic atmosphere disturbances to be visualized not merely as flat “TEC images,” but in a near-realistic three-dimensional form. This advancement significantly enhances the depth and accuracy of ionospheric research related to seismic events and represents an important milestone in space-based monitoring of earthquakes and tsunamis.
The international team utilized data from Japan’s dense GEONET GNSS observation network, combined with a newly developed three-dimensional reconstruction method known as ICLSF (Ionospheric Correction with Localized Smoothing Filter). Without relying on background models, the method successfully reconstructed high-resolution 3D electron density variations across altitudes ranging from 100 to 1,000 kilometers. The study found that approximately four minutes after the earthquake, circular ionospheric disturbances generated by acoustic wave pulses emerged and were detected six minutes earlier than with conventional two-dimensional approaches, demonstrating the capability of 3D reconstruction techniques to capture earthquake-induced atmospheric responses at an earlier stage.
National Central University has long been dedicated to research in space weather and ionospheric responses to earthquakes and tsunamis. This international collaboration not only underscores NCU’s growing academic influence in global space-based monitoring, but also opens new possibilities for advancing earthquake and tsunami early warning technologies worldwide.
Song, R., Hattori, K., Zhang, X. et al. A case study of the three-dimensional co-seismic ionospheric disturbance evolution. Sci Rep 15, 42209 (2025). https://doi.org/10.1038/s41598-025-26074-1
