Internal wave effects on acoustic propagation
Citable URI
https://hdl.handle.net/1912/6550Abstract
Internal gravity wave induced acoustic fluctuations are reviewed. It is well known
that internal waves cause temporal and spatial variability above and beyond that caused by
mesoscale and larger ocean heterogeneity. Increasingly detailed work over many decades
has shown that deep-ocean internal waves, which have often been parameterized using the
Garrett-Munk spectrum as a guide, are responsible for rapid acoustic field variability at all
propagation ranges. Numerous experiments have shown that various sections of wavefronts
from impulsive sources have fluctuation qualities well-described by theory, simulation, or
both. In contrast, fluctuations in shallow water experiments, although known to be consistent
with those expected from internal waves via theoretical and simulation arguments, are
incompletely described by theories for a number of reasons. These reasons include
nonstationary, inhomogeneous or anisotropic wave environments, unknown geoacoustic
properties, and rapidly changing background currents, all of which prevent detailed
comparison of observation and prediction. At this time, many different shallow-water
internal wave scenarios give rise to similar field fluctuations, within reasonable confidence
intervals for the predictions. This may simplify order-of magnitude fluctuation prediction,
while simultaneously making inversion and highly-detailed prediction problematic.
Description
Underwater Acoustics Measurements (UAM) 1st International Conference “Underwater Acoustic Measurements: Technologies & Results,” 28 June- 1 July 2005, Heraklion, Crete, Greece,
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Suggested Citation
Proceedings of the 1st International Conference and Exhibition on "Underwater Acoustic Measurements: Technologies & Results" (2005)Related items
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