Acoustic Resonance of the Atmospheric at 3.7 Hz.
Acoustic Resonance of the Atmospheric at 3.7 Hz.
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3.7 Hz 大气声共振。
DOI：
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
M. Tahira
中科院分区：
文献类型：
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作者：
M. Tahira
本文采用一个基于1986年COSPAR国际参考大气的具有实际温度结构的层模型，讨论了具有水平波阵面的平面声重力波的垂直传播。正常模式的声共振发生在地面和上层中间层之间，频率为3.64-3.69 mHz。由于具有这些频率的声波在声学截止通常为4.1mHz左右的上层中间层中是瞬逝的，因此从下面传播的波能量的一部分被向下反射以干扰向上传播的波，从而引起模型共振。计算出的共振频率与1982年El Chichon和1991年皮纳图博火山爆发的瑞利波中的两个主频率中的较低频率（3.7 MHz）相一致。它也同意较低的频谱成分的电离层次声波所观察到的高频多普勒雷达技术与强对流风暴在热带以下。
Abstract Vertical propagation of plane acoustic-gravity waves with horizontal wave fronts is discussed using a layer model with realistic temperature structure based on the Cospar International Reference Atmosphere, 1986. Acoustic resonance of a normal mode occurs between the ground and upper mesosphere, at a frequency of 3.64–3.69 mHz. Since acoustic waves with these frequencies are evanescent in the upper mesosphere where the acoustic cutoff is normally around 4.1 mHz, part of the wave energy propagated from below is reflected downward to interfere with the upward-propagating waves, thus causing model resonance. The computed resonant frequency coincides with the lower (3.7 mHz) of the two dominant frequencies found in the Rayleigh wave from the eruptions of El Chichon in 1982 and Mount Pinatubo in 1991. It also agrees with the lower spectral component of the ionospheric infrasonic waves observed by the high-frequency Doppler radar technique in association with severe convective storms below in the tropo...