Ionospheric disturbances over South America related to Tonga Volcanic Eruption

Abstract On January 15, 2022, we observed various unusual atmospheric wave events over South America: Atmospheric pressure waves (Lamb mode) around 12:30 to 17:30 UT, tsunamis along the Chilean coast at around 17:00 to 19:00 UT, and ionospheric disturbances between 11:30 and 20:00 UT. We understand that these events were generated by the Tonga volcanic eruption that occurred at (20.55°S, 175.39°W) in South Pacific Ocean at 04:15 UT. Several traveling ionospheric disturbances (TIDs), the horizontal wavelengths of 330 to 1174 km and the phase speed of 275 to 544 m/s were observed before and after the Lamb wave passed over the continent and the arrival of the tsunami on the Chile coast. The observed TID characteristics suggest us that these waves might be generated above the mesosphere far from the observation site. This is the first time to report the signature of ionospheric disturbances over the South American continent generated by the huge volcanic eruption.