Large?Scale Disturbances in the Upper Thermosphere Induced by the 2022 Tonga Volcanic Eruption

The effects of volcanic eruptions on the ionosphere have been well studied, however, evidence for anticipated upper atmospheric neutral variations and their exact extents change are rarely available. Here, we report dramatic thermospheric disturbances following 15 January 2022 Tonga eruption. GRACE-FO Swarm-C observations from accelerometers exhibited three successive density waves at ?500 km altitudes propagating concentrically across globe 200–450 m/s phase speed two converged antipode epicenter. A large-scale long-lasting depletion within a radius approximately 10,000 around epicenter occurred, along with enhancement Such an is comparable in relative intensity respect to no-eruption condition, effect moderate geomagnetic storm. This study offers observational substantial global perturbations above origin near Earth's surface due