Analysis of vertical atmospheric disturbances induced by volcanic eruptions using GNSS CORS and TROPOMI data

Volcanic eruptions can trigger significant changes in both the troposphere and ionosphere. This study analyzes the impact of eruptions from three active volcanoes in Indonesia: Mount Ibu (15 January 2025), Mount Marapi (3 April 2025), and Mount Lewotobi Laki-laki (20 March 2025). We combined global navigation satellite system (GNSS) data and Sentinel-5P TROPOMI satellite imagery to analyze fluctuations in total electron content (TEC), Precipitable water vapor (PWV), zenith hydrostatic delay (ZHD), and sulfur dioxide (SO 2 ) gas distribution to evaluate atmospheric changes caused by eruptions. Results show that only the eruption of Mount Lewotobi Laki-laki, with an 8 km high ash column, triggered significant ionospheric disturbances indicated by TEC fluctuations resembling traveling ionospheric disturbances (TIDs) with anomaly magnitudes of reaching up to ∼8 TECU, with typical fluctuations of 3–5 TECU. In contrast, the eruptions of Mount Ibu and Marapi were weaker and had no measurable ionospheric impact. ZHD remained stable during all events, showing the insensitivity of dry air components to eruptions. PWV exhibited inconsistent local fluctuations. Meanwhile, SO 2 levels increased sharply during eruptions, especially at Mount Lewotobi Laki-laki reaching a maximum value of 255.593 × 10 −4 mol/m 2 making it the most sensitive indicator of volcanic activity. These findings highlight the importance of multi-source GNSS and satellite approaches for atmospheric monitoring due to volcanic activity and their role in supporting more responsive and comprehensive disaster mitigation systems.