标题： 大气细尺度层状结构对碎片陨石次声信号的影响 显示英文标题

标题： Effect of a Fine-Scale Layered Structure of the Atmosphere on Infrasound Signals from Fragmenting Meteoroids

摘要： 我们研究了大气中细尺度（FS）层状结构对由陨石碎裂产生的次声波信号传播的影响。 使用伪微分抛物方程（PPE）方法，我们模拟了35-100公里高度处点源的宽带声学信号。 平流层（37-45公里）和低热层（100-120公里）中FS波动的存在会改变射线轨迹，导致地面站出现多次到达和延长的信号持续时间。 特别是，在80-100公里高度碎裂的陨石可以在150公里以上范围产生两个明显的热层到达，而下降至50公里或更低的陨石则通过反引导传播和衍射在声学阴影区产生弱且持续时间长的到达。 与观测到的次声数据比较证实，FS层状不均匀性可以解释多到达的“N波”，拓宽了对陨石信号的解释可能性。 这些结果也适用于其他进入大气的物体，如样本返回舱，强调了FS结构对冲击波传播的影响。 我们的发现推进了对分层大气中波场演化的理解，并对全球范围内的次声监测具有广泛的相关性（例如，再入舱、火箭发射和大规模爆炸）。 显示英文摘要

摘要： We investigate the influence of a fine-scale (FS) layered structure in the atmosphere on the propagation of infrasound signals generated by fragmenting meteoroids. Using a pseudo-differential parabolic equation (PPE) approach, we model broadband acoustic signals from point sources at altitudes of 35-100 km. The presence of FS fluctuations in the stratosphere (37-45 km) and the lower thermosphere (100-120 km) modifies ray trajectories, causing multiple arrivals and prolonged signal durations at ground stations. In particular, meteoroids fragmenting at 80-100 km can produce two distinct thermospheric arrivals beyond 150km range, while meteoroids descending to 50 km or below yield weak, long-lived arrivals within the acoustic shadow zone via antiguiding propagation and diffraction. Comparison with observed infrasound data confirms that FS-layered inhomogeneities can account for multi-arrival "N-waves," broadening potential interpretations of meteoroid signals. The results also apply to other atmospheric-entry objects, such as sample return capsules, emphasizing how FS structure impacts shock wave propagation. Our findings advance understanding of wavefield evolution in a layered atmosphere and have broad relevance for global infrasound monitoring of diverse phenomena (e.g., re-entry capsules, rocket launches, and large-scale explosions).