Acoustic Resonance between Ground and Thermosphere

Data Science Journal

H. Shinagawa⁴  Y. Tabata⁵  N. Oshiman⁶  M. Nose²  M. Utsugi²  Y. Tanaka¹  Y. Odagi²  M. Matsumura²  D. Han³  T Iyenori² 

[1] Faculty of Engineering, Setsunan University;Graduate School of Science, Kyoto University;Polar Research Institute of China;National Institute of Information and Communications Technology;Research Institute for Sustainable Humanosphere, Kyoto University;Disaster Prevention Research Institute, Kyoto University

关键词: infrasound;    acoustic resonance;   

DOI  :  10.2481/dsj.8.S68

学科分类：计算机科学（综合）

来源: Ubiquity Press Ltd.

【 摘 要 】

References(15)Ultra-low frequency acoustic waves called "acoustic gravity waves" or "infrasounds" are theoretically expected to resonate between the ground and the thermosphere. This resonance is a very important phenomenon causing the coupling of the solid Earth, neutral atmosphere, and ionospheric plasma. This acoustic resonance, however, has not been confirmed by direct observations. In this study, atmospheric perturbations on the ground and ionospheric disturbances were observed and compared with each other to confirm the existence of resonance. Atmospheric perturbations were observed with a barometer, and ionospheric disturbances were observed using the HF Doppler method. An end point of resonance is in the ionosphere, where conductivity is high and the dynamo effect occurs. Thus, geomagnetic observation is also useful, so the geomagnetic data were compared with other data. Power spectral density was calculated and averaged for each month. Peaks appeared at the theoretically expected resonance frequencies in the pressure and HF Doppler data. The frequencies of the peaks varied with the seasons. This is probably because the vertical temperature profile of the atmosphere varies with the seasons, as does the reflection height of infrasounds. These results indicate that acoustic resonance occurs frequently.

【 授权许可】

Unknown