On 15 January 2022, at 1227 hours (China Standard Time) , the Hunga Tonga volcano (20.5 ¡ã S, 175.4 ¡ã W) erupted in the Tonga Sea, triggering a local tsunami and a strong shock wave in the atmosphere. After the volcanic eruption, infrasound analysis was carried out based on infrasound observation array in capital circle, Yunnan and Sichuan. The preliminary analysis results show that all infrasound arrays in China have observed the infrasound caused by the volcanic eruption. The details are as follows:

1.Infrasound Direct Wave: the Infrasound Array in the capital circle (9,760 km) observed a direct infrasound wave caused by volcanic activity at 21:07 China Standard Time January 15, with a propagation time of about 8.7 hours, the group velocity is about 1127kph, infrasound time is about 21:35 in Lijiang, Yunnan Province (10,500 km from the volcano) , 21:28 in Xichang, Sichuan province (10,380 km from the volcano) The duration of each station was more than 2 hours and the peak amplitude was more than 20PA.

2. Infrasonic reverse wave: infrasonic wave from volcanic eruption propagates in the opposite direction along the great circle of the Earth. The infrasound array in the capital circle (30,240 km) received the infrasonic wave at 14:55 on January 16, and the propagation time is about 26.5 hours, the group velocity is about 1,130 km per hour, the time of receiving the infrasound is about 14:35 on January 16 in Lijiang, Yunnan Province, which is 29,500 km away from the volcano, and about 14:25 on January 16 in Xichang, Sichuan province, which is 29,620 km away from the volcano Each station lasted more than 1 hour and the peak amplitude was more than 5Pa.