A Study of the Infrasonic Wave in the Atmosphere

[摘要] This paper presents a study of infrasonic waves generated by the explosions of the volcano Sakura-jima, and detected by the microphone array in Kariya, at a distance of about 710km. The geometric ray analyses using the rawinsonde and rocketsonde data show that these infrasonic waves are channeled mainly in the tropospheric duct, formed by the strong westerly wind in the upper troposphere. The propagation in the stratospheric duct which is also significant in winter season, is less frequent owing to the occasional destruction of the winter westerlies by the stratospheric Aleutian anticyclone over Japan.The infrasonic signals may provide a tool to monitor the upper stratospheric flow, if combined with the temperature data from satellite observations.

[学科分类] 大气科学