Analysis of plasma bubble phenomena and their geomagnetic dependencies using GNSS-TEC with 3D tomography investigation

Abstract This study investigates the phenomenon of plasma bubbles in the ionosphere using GNSS Total Electron Content (TEC) data and 3D tomography to analyze the spatial and temporal distribution of electron density anomalies. This research covers five global regions: Japan, Australia, Europe, Brazil, and Tonga, using GNSS observation data with approximately 1,214 data in Japan, 264 in Australia, 263 in Europe, and 159 in Brazil. The data spans different collection periods, with observations made on March 1, 2013 (DOY 060) for Japan and Australia, June 22–23, 2015 (DOY 173–174) for Europe, January 3, 2014 (DOY 003) for Brazil, and January 15, 2022 (DOY 015) for Tonga. The study highlights a strong negative correlation between geomagnetic disturbances, indicated by the Dst Index, and the maximum height of TEC anomalies caused by plasma bubbles. A linear regression analysis yielded a high correlation coefficient of 0.9949, suggesting that stronger geomagnetic storms (more negative Dst Index) result in plasma bubbles forming at higher altitudes. Additionally, the Kp Index shows a moderate positive correlation with TEC anomaly height, indicating that higher geomagnetic activity (larger Kp Index) is also associated with higher plasma bubble altitudes. The analysis reveals that plasma bubbles typically form at altitudes between 200 km and 600 km, with the maximum height of anomalies reaching an average of around 500 km. This research enhances our understanding of ionospheric disturbances and their impact Fseveon satellite navigation and communication systems, providing valuable insights into space weather dynamics.