PHYSICAL EFFECTS OF THE POWERFUL TONGA VOLCANO EXPLOSION IN THE EARTH – ATMOSPHERE – IONOSPHERE – MAGNETOSPHERE SYSTEM ON JANUARY 15, 2022
Authors:   V. N. Karazin Kharkiv National University, Chernogor L.F. 
Published: June 2023

The Tonga volcano explosion has already been considered in many papers, which investigate the effects of tsunamis, explosiveatmospheric waves, traveling ionospheric disturbances, the perturbations of the equatorial anomaly, rearrangement of the ionospheric currents and of the atmospheric wind pattern, disturbances in the geomagnetic field, etc. It is reliably established that the explosion of the Tonga volcano caused a number of processes on a global scale. However, the mo deling of these processes is absent in the literature. The volcano is able to launch a whole complex of physical processes in all geophysical fields of the Earth (lithosphere, tectonosphere, ocean) – atmosphere – ionosphere – magnetosphere (EAIM) system. Analysis of the entire set of processes in the system caused by a unique explosion and volcanic eruption is a pressing scientific issue. The scientific objective of this study is to perform a comprehensive analysis and modeling of the main physical processes within the EAIM system, which accompanied the powerful explosion of the Tonga volcano on January 15, 2022. The article attempts to model or estimate the magnitude of the main effects caused by the explosion and eruption of the Tonga volcano. A comprehensive analysis and modeling of the main physical processes in the EAIM system, which accompanied the powerful explosi on and eruption of the Tonga volcano on January 15, 2022, has been performed. The energetics of the volcano and the explosive atmospheric wave has been estimated. The thermal energy of the volcano attained ~ 3.9×1018 J, while the mean thermal power has been estimated to be 9.1×1013 W. The energy of the explosive atmospheric wave was about 16–17 Mt TNT. The volcanic flow with an initial pressure of tens of atmospheres was determined to reach a few kilometers height, while the volcanic plume attained the peak altitude of 50–58 k m and moved 15 Mm we stward. The main parameters of the plume have been estimated. The plume’s mean power was 7.5 TW, and its heat flux was 15 MW/m2. With such a flux, one should have expected the appearance of a fire tornado with an ~0.17 s–1 angular frequency or a 37 s tornado rotation period. An analytical relation has been derived for estimating the maximum altitude of the plume rise. The main contribution to the magnitude of this altitude makes the volumetric discharge rate. The volcano explosion was accompanied by the generation of seismic and explosive atmospheric waves, tsunamis, Lamb waves, atmospheric gravity waves, infrasound, and sound, which propagated on a global scale. It is important to note that the powerful explosiveatmospheric wave could launch a secondary seismic wave and a secondary tsunami, which was one of the manifestations of subsystem couplings in the EAIM system. The propagation of powerful waves was accompanied by non-linear distortions of the wave profiles and non-linear attenuation as a result of the self-action of the waves. The electric processes in the troposphere are associated with spraying the eruption products, the electrification of the constituent particles in the plume, a charge separation, perturbations in the global electric circuit, and with an increase in the atmospheric electric field, the electric conductivity, and the electric current. The electric effect in the ionosphere is due to an increase in the strength of the ionospheric electric field by one or two orders of magnitude, which resulted in the secondary processes in the magnetosphere and the inner radiation belt. The magnetic effect of the submarine volcano explosion and eruption was established to be significant (~100–1,000 nT) but local. The magnetic effect in the ionosphere was due to the perturbations of the ionospheric dynamo current system under the action of the ionospheric hole (B ~ 0.1–1 nT) and due to the generation of the external current in the field of atmospheric waves (B ~ 1–10 nT). Dusting the atmosphere with the eruption plume led to the scattering of solar radiation by aerosols, the disturbance of the radiation balance in the Earth’s surface–ocean–atmosphere system, the cooling of the atmosphere at the airearth boundary, and the trigger effect. The volcano explosion caused the generation of aperiodic (ionospheric hole) and quasisinusoidal (wave) perturbations. Wave perturbations exhibited two characteristic speeds, ~300 m/s, which is close to the speed of the Lamb wave, and 700–1,000 m/s, which are typical for atmospheric gravity waves at ionospheric heights. The magnetospheric effects, first of all, are caused by powerful electromagnetic waves in the ~ 10–100 kHz range from tens to hundreds of thousands of lightning discharges that occurred in the volcanic plume. The energy and power of these radio emissions have been estimated to be 40–400 GJ and 40–400 GW, respectively. These emissions acted to cause precipitation of relativistic electrons from the radiation belt into the ionosphere and to enhance the ionization in the ~70–120 km altitude range. It is important to note that the burs t of precipitation was triggered. The Alfvén waves that propagated from their source along magnetic field lines had a certain effect on the magnetosphere. The direct and reverse, positive and negative couplings between the components of the EAIM system have been determined and validated.