Topographically Scattered Infrasound Waves Observed on Microbarometer Arrays in the Lower Stratosphere
- Univ. of North Carolina, Chapel Hill, NC (United States); Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
- Univ. of North Carolina, Chapel Hill, NC (United States)
- Swedish Institute of Space Physics (IRF), Kiruna (Sweden)
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
When an acoustic wave strikes a topographic feature, some of its energy is scattered. Sensors on the ground cannot capture these scattered signals when they propagate at high angles. We report observations of upwardly-scattered acoustic waves prior to refraction back to the ground, intercepting them with a set of balloon-borne infrasound microbarometers in the lower stratosphere over northern Sweden. We show that these scattered waves generate a coda whose presence can be related to topography beneath balloons and low-altitude acoustic ducts. The inclination of the coda signals changes systematically with time, as expected from waves arriving from scatterers successively closer to receivers. The codas are present when a temperature inversion channels infrasound from a set of ground chemical explosions along the ground, but are absent following the inversion's dissipation. Since scattering partitions energy away from the main arrival, these observations imply a mechanism of amplitude loss that had previously been inaccessible to measurement. As such, these data and results allow for a better comprehension of interactions between atmospheric infrasound propagation and the solid earth
- Research Organization:
- Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
- Sponsoring Organization:
- USDOE National Nuclear Security Administration (NNSA)
- Grant/Contract Number:
- NA0003525
- OSTI ID:
- 1870466
- Report Number(s):
- SAND2022-3940J; 704735
- Journal Information:
- Earth and Space Science, Journal Name: Earth and Space Science Journal Issue: 4 Vol. 9; ISSN 2333-5084
- Publisher:
- Wiley, American Geophysical UnionCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Origin and mitigation of wind noise on balloon-borne infrasound microbarometers