Estimates of Vertical Mixing by Internal Waves Reflected off a Sloping Bottom

1988 ◽  
pp. 405-423 ◽  
Author(s):  
Christopher Garrett ◽  
Denis Gilbert
Keyword(s):  
Internal Waves ◽  
Vertical Mixing ◽  
Sloping Bottom

scholarly journals Internal waves and vertical mixing in the Storfjorden Polynya, Svalbard

2011 ◽  
Vol 116 (C12) ◽  
Author(s):  
F. P. Jardon ◽  
P. Bouruet-Aubertot ◽  
Y. Cuypers ◽  
F. Vivier ◽  
A. Lourenço
Keyword(s):  
Internal Waves ◽  
Vertical Mixing

Second-mode nonlinear internal waves over a sloping bottom

2013 ◽  
Vol 59 (1) ◽  
pp. 62-67 ◽  
Author(s):  
A. S. Belogortsev ◽  
S. A. Rybak ◽  
A. N. Serebryanyi
Keyword(s):  
Internal Waves ◽  
Nonlinear Internal Waves ◽  
Second Mode ◽  
Sloping Bottom

Idealized Numerical Modelling of Internal Waves Through Density Staircases

2021 ◽  
Author(s):  
Mikhail Schee ◽  
Nicolas Grisouard
Keyword(s):  
Internal Waves ◽  
Laboratory Experiments ◽  
Equations Of Motion ◽  
Vertical Mixing ◽  
Boussinesq Equations ◽  
The Arctic ◽  
Inertial Wave ◽  
Ice Floes ◽  
Mixed Layers ◽  
Transmission And Reflection

<p>The Arctic Ocean contains a warm layer originating from the Atlantic Ocean below the pycnocline which has a thermohaline staircase structure that inhibits vertical mixing. If this heat were to rise to the surface, the rate of sea ice loss would increase dramatically. Wind stress and ice floes generate internal waves which can cause vertical mixing. As the ice cover in the Arctic continues to decline, it will be important to predict how these changing internal waves propagate through such stratification profiles. Here, we investigate how density staircases enhance or limit downward near-inertial wave propagation. We use direct numerical simulations to solve the Boussinesq equations of motion using spectral methods. We simulate the propagation of internal waves through a vertically stratified fluid which includes one or more steps (i.e., mixed layers). We find that we reproduce the results of laboratory experiments showing transmission and reflection of internal waves from one or two mixed layers. We then extend our parameter regime to simulate the propagation of internal waves through a more realistic stratification profile tending toward that of the Arctic pycnocline.</p>

scholarly journals Variability in the Internal Wave Field Induced by the Atlantic Deep Western Boundary Current at 16°N

2014 ◽  
Vol 44 (2) ◽  
pp. 492-516 ◽  
Author(s):  
Janna Köhler ◽  
Christian Mertens ◽  
Maren Walter ◽  
Uwe Stöber ◽  
Monika Rhein ◽  
...  
Keyword(s):  
Internal Wave ◽  
Wave Field ◽  
Continental Slope ◽  
Internal Waves ◽  
Vertical Mixing ◽  
Low Frequency ◽  
Western Boundary Current ◽  
Western Boundary ◽  
Boundary Current ◽  
Deep Western Boundary Current

Abstract Five years of continuous mooring data combined with conductivity–temperature–depth (CTD)/lowered acoustic Doppler current profiler (LADCP) measurements from five cruises are used to investigate the influence of the deep western boundary current (DWBC) on the internal wave field and associated vertical mixing at the continental slope at 16°N in the western Atlantic. The mooring data include 2-hourly rotor current-meter measurements and temperature/conductivity time series with a high temporal resolution of 5–20 min. Thus, the data resolve time scales ranging from the low-frequency variability of the large-scale DWBC that generates internal waves due to interactions with the topography to frequencies greater than that of internal waves that are associated with vertical mixing. Estimates of the vertical mixing induced by the breaking of the observed internal waves show elevated diapycnal diffusivities of up to 10−3 ± 0.4 × 10−3 m2 s−1 in the bottommost 1500 m during times of a strong DWBC (maximum velocities at the mooring site up to 50 cm s−1) whereas vertical mixing rates are about an order of magnitude lower (1.6 × 10−4 ± 0.6 × 10−4 m2 s−1) during weak flow. During periods of a strong DWBC, spectra of horizontal velocity and internal wave available potential energy change substantially at depths below 1200 m and show a strong increase in variance particularly in the near-inertial frequency band. Low-frequency, near-inertial waves generated by topography/DWBC interaction on the slope to the west of the moorings can potentially cause this observed wave intensification; ray paths estimated for these waves agree well with the observed spectral changes at different depths. Variability in the high-frequency range, considered as a proxy for turbulent mixing, is significantly correlated with the DWBC strength above the continental slope.

scholarly journals Evidence of Vertical Mixing Caused by High Frequency Internal Waves along the Eastern Coast of Korea

2008 ◽  
Vol 11 (1) ◽  
pp. 41-49
Author(s):  
In-Seong Han ◽  
Ju Lee ◽  
Lee-Hyun Jang ◽  
Young-Sang Suh ◽  
Ki-Tack Seong
Keyword(s):  
Internal Waves ◽  
High Frequency ◽  
Vertical Mixing ◽  
Eastern Coast

scholarly journals Vertical Boundary Mixing Events during Stratification Govern Heat and Nutrient Dynamics in Windy Tropical Lakes with High Water-Level Fluctuations: A Long-Term (2001-2018) Study

2021 ◽  
Author(s):  
Martín Merino Ibarra ◽  
Jorge A. Ramírez-Zierold ◽  
Patricia M. Valdespino-Castillo ◽  
Fermin S. Castillo-Sandoval ◽  
Andrea P. Guzmán-Arias ◽  
...  
Keyword(s):  
Water Level ◽  
Internal Waves ◽  
Nutrient Dynamics ◽  
Inorganic Nitrogen ◽  
Vertical Mixing ◽  
Nutrient Flux ◽  
Water Level Fluctuations ◽  
Diffusivity Coefficient ◽  
Boundary Mixing ◽  
Stratified Lakes

Physical processes play important roles in controlling eutrophication and oligotrophication. In stratified lakes, internal waves can cause vertical transport of heat and nutrients without breaking the stratification, through boundary mixing events. Such is the case in tropical Valle de Bravo (VB) lake, where strong diurnal winds drive internal waves, boundary mixing and hypolimnetic warming during stratification periods. We monitored VB during 18 years (2001-2018) when important water-level fluctuations (WLF) occurred, affecting mixing and nutrient flux. Mean hypolimnetic temperature increase (0.06–1.04°C month-1) occurred in all the stratifications monitored. We analyzed temperature distributions and modeled the hypolimnion heat budget to assess vertical mixing between layers (26,618–140,526 m-3h-1), vertical diffusivity coefficient KZ (6.2x10-7–3.3x10-6 m2s-1) and vertical nutrient entrainment to epilimnion on monthly scale. Stability also varied as a function of WLF. Nutrient flux to the epilimnion ranged 0.36–5.99 mg m-2d-1 for soluble reactive phosphorus (SRP) and 5.8–97.1 mg m-2d-1 for dissolved inorganic nitrogen (DIN). During low water-level years, vertical nutrient fluxes increase and can account for up to >40% of the total external nutrients load to the lake. Vertical mixing changes related to WLF affect nutrient recycling, their flux to sediments, ecosystemic metabolic balance and planktonic composition of VB.

The fate and impact of internal waves induced by strong shear current over a marginal ridge

2020 ◽  
Author(s):  
Peiwen Zhang ◽  
Wenjia Min
Keyword(s):  
Internal Wave ◽  
Internal Waves ◽  
Vertical Mixing ◽  
Internal Tide ◽  
Stratified Flow ◽  
Internal Tides ◽  
Energy Field ◽  
Nonlinear Internal Waves ◽  
Highly Nonlinear ◽  
Shear Current

<p>Internal waves with strong vertical mixing could be induced by stratified flow over seafloor obstacles. Noted that the stratified flow not only trigger internal tides, but also highly nonlinear internal waves like internal lee waves and internal solitary waves over steep topography features, and the highly nonlinear internal waves are suggested to play an important role in turbulence and mixing. As a typical seafloor obstacle, ridge could significantly modified the propagation of internal tide, internal lee wave and internal solitary wave. We focused on I-Lan ridge with asymmetrical topography feature in Kuroshio region. To the north of the I-Lan ridge, the depth of Philippine basin reached 4000m compared with the depth of 1500m in the south of the ridge, leading to different characteristics of internal wave energy field and ecological characteristics between two sides. Based on numerical simulations, we revealed the generation and propagation of internal waves over marginal ridge, causing by the shear current induced by Kuroshio. We also discussed the turbulence kinetic energy contributed by linear internal waves and nonlinear internal waves, providing the strength of vertical turbulent mixing around the I-Lan ridge. Then we demonstrated the characteristics of complex internal wave field in the strong background shear current over I-Lan ridge.</p>

Sign in / Sign up

Export Citation Format

Share Document