Investigating Multiple Ionospheric Disturbances Associated with the 2020 August 4 Beirut Explosion by Geodetic and Seismological Data

In this study, we investigated oscillatory disturbances in the atmosphere [from GNSS-derived ionospheric slant total electron content (STEC)] and in the solid Earth (from triaxial seismic data) following the 4 August 2020 Beirut port explosion in Lebanon. The ionospheric disturbances were investigated under meticulous observations of the space weather indices. The STEC sequences were analyzed by the Savitzky-Golay smoothing filter to check the ionospheric response to the blast. Our results showed that the induced wave structures have significant multiple ionospheric disturbances associated with the explosion epicenter. The research findings showed that the ionosphere responds to the severe blast with two time arrivals. The first time arrival was after the blast within a few minutes and had a low frequency. The second time arrival for the ionospheric disturbance was after > 2 h from the explosion time with high frequency compared with the first one. These ionospheric disturbances were associated with the time and space of the blast. The speed of induced waves in the northern direction of the explosion was slower than the waves in the western and the southern directions, respectively. Finally, the seismological data revealed that there were two major blasts in the Beirut port. The first blast triggered a severe blast after 5 s. Our results are a significant indication that the ionospheric disturbances are influenced by the acoustic gravity wave activity induced by the blast rather than by other random events.