

Topography and Infrasound

Topographic effects on infrasound propagation have been widely
discussed, based mainly on ground based observations and modeling (\cite{Chimonas1977,
McKenna2012, Lacanna2014}).
These deployments showed that considerable distortion of acoustic infrasound waves occur when
significant topographic variations (mountains, ridges)
interact with the propagating waves.
Distortions can affect estimation of source parameters with profound effect on
monitoring capabilities.
In volcanic regions waveform simulation is strongly depedant on
topographic effects \cite{Kim2014 ,Kim2015, Kim2015b, Kim2016}.
Yield estimates and source time function extraction
for volcanic eruptions and nuclear and chemical
explosions can be severely comprimised by topographic effects
\cite{VERGOZ2022, Kim2014 ,Kim2015b, Toney2023}.

In this paper, however, we have a unique source that provides
an impulsive broadband source propagating directly into
a floating array above the desert floor.
The clear reflected waves illustrate, with great clarity, the severe effect the topographic
variation has on the scattered waves once they interact with the surface.







Key references (shortlist)

Bird, E. J., et al., Topographically Scattered Infrasound Waves Observed on Microbarometer Arrays in the Lower Stratosphere — demonstrates observed scattered infrasound codas tied to surface topography and atmospheric ducts. 
Agupubs
+1

“Topographic effects on infrasound propagation” (JASA, 2012) — a focused study on how surface topography influences infrasound propagation and local arrivals. Good for a compact, tecnhical overview. 
AIP Publishing

Lacanna, G. et al., Influence of near-source volcano topography on the infrasound field (2013) — explores how volcano topography modifies infrasound from eruptions (modeling + observations). Useful if you’re interested in volcanic infrasound/topography coupling. 
ScienceDirect

Fee, D., et al. (work cited in later volcano studies) — used numerical Green’s functions and realistic topography in infrasound inversions (example application to Sakurajima). Good example of full-3D topography in inversion work. 
SpringerLink

Toney, L. & coauthors, Examining Infrasound Propagation at High Spatial Resolution / related ERDC/AVO reports (2023) — dense-array observations and discussion of how local topography and atmosphere produce secondary infrasound arrivals. 
laro.lanl.gov
+1

Albert, S. A., Tracking scattered signals in the acoustic coda using ICA (GJI, 2019) — methods to separate and identify coda components produced by scattering from complex topography. Useful for signal processing side of topographic scattering. 
OUP Academic

Hickey, M. P., Numerical Modeling of the Propagation of Infrasonic Acoustic Waves (2019 thesis/paper) — numerical simulations of infrasound interacting with mountain-induced turbulence and topography. Good for numerical approach details. 
Scholarly Commons
+1

LLNL / ElAc modeling overview — high-performance modeling that explicitly includes scattering from complex topography and turbulent atmosphere (code & application note). Useful as an applied/numerical modeling reference. 
str.llnl.gov

Chimonas, G., Atmospheric/mountain infrasound work (1977/older studies) — classic literature on infrasound generation/propagation near mountains and seasonal effects (helps with historical context). 
American Meteorological Society Journals

Broader reviews & related topics: (a) IMS global observations and acoustic-gravity wave catalogs (useful for large-scale context), (b) reviews on acoustic waves in turbulent atmosphere. These place topographic scattering into the wider infrasound literature. 
ScienceDirect
+1

How these documents are useful (quick guide)

Observations demonstrating topographically generated scattered arrivals / codas: Bird (2022), Toney (2023), volcano case studies. 
Agupubs
+1

Modeling/numerical approaches that include full 3-D topography and scattering: Fee et al. (volcanic inversion examples), ElAc/LLNL, Hickey (numerical thesis). 
SpringerLink
+2
str.llnl.gov
+2

Signal-processing strategies to identify and separate scattered coda signals: Albert (2019). 
OUP Academic

Reviews & classical theory on scattering in atmosphere/turbulence context: JASA 2012 review & older theory papers.



