The evolution of mode-2 nonlinear internal waves over the northern Heng-Chun Ridge south of Taiwan
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Author
Reeder, D.B.
Ramp, S.R.
Yang, Y.J.
Buijsman, M.C.
Bahr, F.L.
Date
2015Metadata
Show full item recordAbstract
Two research cruises were conducted from the R/V OCEAN RESEARCHER 3 during 05–16 August 2011
to study the generation and propagation of high-frequency
nonlinear internal waves (NLIWs) over the northern Heng-
Chun Ridge south of Taiwan. The primary study site was on
top of a smaller ridge about 15 km wide by 400m high atop
the primary ridge, with a sill depth of approximately 600 m.
A single mooring was used in conjunction with shipboard
observations to sample the temperature, salinity and velocity
structure over the ridge. All the sensors observed a profusion
of mode-2 NLIWs. Some of the waves were solitary, while
others had as many as seven evenly spaced waves per packet.
The waves all exhibited classic mode-2 velocity structure
with a core near 150–200m and opposing velocities in the
layers above and below. At least two and possibly three most
common propagation directions emerged from the analysis,
suggesting multiple generation sites near the eastern side of
the ridge. The turbulent dissipation due to overturns in the
wave cores was very high at order 10¯⁴–10¯³Wkg¯¹. The
energy budget suggests that the waves cannot persist very far
from the ridge and likely do not contribute to the South China
Sea transbasin wave phenomenon.
Description
The article of record as published may be found at http://dx.doi.org/10.5194/npg-22-413-2015