Thermospheric disturbances caused by the propagation of acoustic-gravity waves from the lower atmosphere during a solar eclipse

The Influence of Tropospheric Processes on Disturbances in the D and E Ionospheric Layers

“…Theoretical studies using models describing the propagation of IGWs in the atmosphere in a wide frequency range make it possible to emphasize the main wave features. The propagation of these waves is accompanied by dissipative and waveguide processes that lead to the excitation of secondary IGWs [2,3,31,32,38]. Because of this feature, the characteristics of disturbances created by spatially extended and mobile sources in the atmosphere get complicated.…”

“…It should be noted that the region of a solar eclipse is a mobile and spatially distributed source of disturbances in the atmosphere. Under these conditions, waves are excited that propagate both in the direction of motion of the region of disturbances and in the opposite direction [32]. The resulting picture of the disturbances created by the eclipse region is a superposition of waves propagating in different directions.…”

“…For example, the features of the morphology of the equatorial ionosphere and the ionosphere disturbances during a solar eclipse are considered in [25,26]. As a result of observations and theoretical studies [27][28][29][30][31][32], it was found that propagation of AWs and IGWs upward from the region of meteorological disturbance has a significant effect on the ionosphere. This study's main goal was to experimentally confirm the previously proposed mechanism for transferring the energy of tropospheric disturbances that arise during the passages of the solar terminator and solar eclipse into the ionosphere due to the vertical propagation of acoustic and internal gravity waves.…”

Disturbances of the Thermosphere and the Ionosphere during a Meteorological Storm

“…In practice, it is not always possible to obtain data on pressure variations by direct measurements; therefore, the use of experimental data on the intensity of the lidar signal, as was done in work [63], reduced to the data on pressure variations in the surface layer is effective. Variations in lidar signal intensity reflect the frequency response of pressure variations at a fixed altitude.…”

“…At present, the development of computer technology and the improvement of methods for the numerical integration of hydrodynamic equations make it possible to build models for the generation and propagation of AWs and IGWs in the atmosphere, taking into account nonlinear and dissipative processes, as well as real stratification of the medium, for example [5,9,58,59]. In theoretical research [59][60][61][62][63], it was established that the heat release/absorption processes occurring due to phase transitions of water in the atmosphere during the formation and evolution of clouds and the development of other meteorological phenomena have a significant effect on the state of the thermosphere and ionosphere. However, a significant problem in numerical studies of wave processes in the atmosphere is determining realistic sources of disturbances, as far as the initial and boundary conditions.…”