Continuous long-term analysis on earthquake-related total electron content (TEC) signals across the Mediterranean region.

This study examines the correlation between Total Electron Content (TEC) anomalies and seismic activity in the Mediterranean area over a continuous 19-year period (2002–2021). Key methodological inputs were classified and optimized through simulations, resulting in an improved interquartile range (IQR) method for anomaly detection. The optimized method was applied to identify TEC anomalies correlated with seismic events, with rigorous statistical validation highlighting the robustness of the approach. Results indicate that seismic events of magnitude >5.5 can influence the ionosphere up to 90 days prior to the event and within a 1250 km radius.