FN Archimer Export Format
PT J
TI Noise generation in the solid Earth, oceans and atmosphere, from nonlinear interacting surface gravity waves in finite depth
BT
AF ARDHUIN, Fabrice
HERBERS, T. H. C.
AS 1:1;2:2;
FF 1:PDG-ODE-LOS;2:;
C1 IFREMER, Lab Oceanog Spatiale, F-29280 Plouzane, France.
USN, Postgrad Sch, Dept Oceanog, Monterey, CA 93943 USA.
C2 IFREMER, FRANCE
USN, USA
SI BREST
SE PDG-ODE-LOS
IN WOS Ifremer jusqu'en 2018
copubli-int-hors-europe
IF 2.294
TC 75
UR https://archimer.ifremer.fr/doc/00125/23580/21479.pdf
LA English
DT Article
DE ;acoustics;geophysical and geological flows;surface gravity waves
AB Oceanic pressure measurements, even in very deep water, and atmospheric pressure or seismic records, from anywhere on Earth, contain noise with dominant periods between 3 and 10 s, which is believed to be excited by ocean surface gravity waves. Most of this noise is explained by a nonlinear wave-wave interaction mechanism, and takes the form of surface gravity waves, acoustic or seismic waves. Previous theoretical work on seismic noise focused on surface (Rayleigh) waves, and did not consider finite-depth effects on the generating wave kinematics. These finite-depth effects are introduced here, which requires the consideration of the direct wave-induced pressure at the ocean bottom, a contribution previously overlooked in the context of seismic noise. That contribution can lead to a considerable reduction of the seismic noise source, which is particularly relevant for noise periods larger than 10 s. The theory is applied to acoustic waves in the atmosphere, extending previous theories that were limited to vertical propagation only. Finally, the noise generation theory is also extended beyond the domain of Rayleigh waves, giving the first quantitative expression for sources of seismic body waves. In the limit of slow phase speeds in the ocean wave forcing, the known and well-verified gravity wave result is obtained, which was previously derived for an incompressible ocean. The noise source of acoustic, acoustic-gravity and seismic modes are given by a mode-specific amplification of the same wave-induced pressure field near zero wavenumber.
PY 2013
PD FEB
SO Journal Of Fluid Mechanics
SN 0022-1120
PU Cambridge Univ Press
VL 716
UT 000314422800028
BP 316
EP 348
DI 10.1017/jfm.2012.548
ID 23580
ER
EF