Atmosphere-ionosphere coupling following the Tonga eruption: global multi-scale ionospheric effects

The submarine volcanic eruption at Tonga on 15 January 2022 was a devastated geohazardous rated as VEI (Volcanic Explosivity Index) 5-6, which was the most powerful since the 1883 Krakatoa VEI 6 eruption. The release of enormous amounts of energy into the atmosphere triggered significant geophysical disturbances. In this presentation, we provide various upper atmospheric observations to demonstrate local, regional, and global ionospheric disturbances, including TID global propagation with the most intense, persistent, and consistent wave mode at 300-350 m/s phase speed , EIA deformation and x-cross pattern of EIA crest evolution, equatorial irregularities and bubbles, substantial plasma density depletion. Timing of these and many other observed ionospheric responses was consistent with the Lamb wave arrival, despite of other waves including acoustic and gravity waves as well as tsunami waves were also present in specific regions.  The eruption-excited atmospheric waves produced not only TID global propagation but also modulated the wind dynamos in both E and F regions, driving electrodynamic changes closely associated with EIA and EPBs phenomena at equatorial and low latitudes. These results suggested a new vertical coupling channel through which the intense atmospheric surface disturbance processes can produce far-reaching and long-lasting geospace impacts.