The relations describing the reflection of three-dimensional acoustic ray paths impinging on a non-flat surface are derived and used to approximate the propagation of infrasonic signals over irregular terrain in the geometric limit. The influence of non-flat ground is strongest for those paths that reflect off the surface multiple times, such as those in the tropospheric waveguide; however, notable differences in source and receiver elevations for stratospheric and thermospheric paths can produce notable differences in travel times and arrival amplitudes. The interaction of ray paths with topographical features is investigated using a simple hill to demonstrate the impact of topography on propagation within an azimuthal plane, as well as cases in which the ground surface interaction deflects the path out of the azimuthal plane. Finally, broadband waveform predictions are compared with observations for an event in the western U.S., and a statistical analysis of scattering losses due to interaction with topography in the limit of geometric acoustics is used to improve the agreement between predicted and observed infrasonic signals.

中文翻译：

---

不规则地形对对流层次声传播的影响

得出描述撞击在非平坦表面上的三维声波路径反射的关系，并将其用于在几何极限内近似次声信号在不规则地形上的传播。对于那些多次反射离开地面的路径，例如对流层波导中的路径，非平坦地面的影响最大。但是，平流层和热层路径的源高度和接收高度的显着差异可能会导致传播时间和到达幅度产生显着差异。使用一个简单的小山来研究射线路径与地形特征的相互作用，以证明地形对方位平面内传播的影响，以及地表相互作用将路径偏转到方位平面之外的情况。最后，