Occurrence of Nighttime Irregularities and Their Scale Evolution in the Ionosphere Due To the Solar Eclipse Over East Asia on 21 June 2020

Abstract

The moon obscuration of a solar eclipse is a transient solar-terrestrial phenomenon that generates a rapid regional sunset in the Earth's atmosphere and ionosphere in the daytime, which causes plasma irregularities in both the ionospheric F-and E-region during the obscuration (

Numerical Solution of the Atmospheric Perturbations Triggered by Persistent Lithospheric Vibrations

“…The solution reveals that the persistent vibrations in a wide area on the ground (>10 5 km 2 , mainly corresponding to the area of Sichuan Province, China 4.86 × 10 5 km 2 (https://www.sc.gov.cn/, accessed on 8 March 2022) is capable of decaying rapidly in the z direction of the cylinder. The rapid decay of large disturbance agrees with the observational evidences of a large disturbances tend to evolve into finer-scale in the atmosphere [75,76].…”

“…The new idea of the simulation in this study is considering the persistent variation in a wide area. In other words, the numerical results reveal that persistent ground vibrations in a wide area are possible to evolves into small-scale perturbations in the atmosphere [76]. Figure 2c shows that vertical velocity gradually increases with height, and finally reach 100 m/s at 100 km altitude.…”

“…We calculated the numerical solution of the disturbance equations in the cylindrical symmetric coordinate to understand the possible effect of the persistent lithospheric vibrations on the upper atmosphere, which is a preliminary result for explaining the possible relation between the vibration signals on the ground and those in the atmosphere above. The solution reveals that the persistent vibrations in a wide area on the ground (>10 5 km 2 , mainly corresponding to the area of Sichuan Province, China 4.86 × 10 5 km 2 (https://www.sc.gov.cn/, accessed on 8 March, 2022) is capable of decay- Previous studies simulate the atmospheric acoustic or gravity waves triggered by a point source [75][76][77]. The new idea of the simulation in this study is considering the persistent variation in a wide area.…”

“…Matsumura et al [72] simulated the atmospheric perturbations observed at 300-km altitude just after the 2011 off the Pacific coast of Tohoku Earthquake, and the results showed remarkable agreement with the observed TEC oscillations qualitatively. Most of the previous studies simulate the atmospheric acoustic or gravity waves triggered by a point source [60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76][77], while the ground vibrations are typically observed in a wide area [52]. Therefore, the innovation of the simulation in this study considers the persistent variation in a wide area.…”

Nighttime ionospheric disturbances and irregularities due to solar eclipse at June solstice in 2020

“…Yang-Yi Sun* (1) , Cheih-Hung Chen (1) , and Jin Wang (1) (1) School of Geophysics and Geomatics, China University of Geosciences, Wuhan, e-mail: sunyy@cug.edu.cn A solar eclipse is a daytime phenomenon that significantly disturbs the ionosphere and triggers irregularities during the moon obscuration. However, the nighttime disturbances and irregularities that occurred after an eclipse remain unknown.…”