Large scale circulation induced by small scale surface gravity waves

2007 ◽  
pp. 411-415
Author(s):  
Francesco Califano ◽  
Andre Mangeney
Keyword(s):  
Gravity Waves ◽  
Large Scale ◽  
Surface Gravity ◽  
Small Scale ◽  
Large Scale Circulation ◽  
Surface Gravity Waves ◽  
Scale Surface

scholarly journals Thickness-Weighted Mean Theory for the Effect of Surface Gravity Waves on Mean Flows in the Upper Ocean

2012 ◽  
Vol 42 (5) ◽  
pp. 725-747 ◽  
Author(s):  
Hidenori Aiki ◽  
Richard J. Greatbatch
Keyword(s):  
Gravity Waves ◽  
Large Scale ◽  
Turbulent Viscosity ◽  
Residual Effect ◽  
Surface Gravity ◽  
Upper Ocean ◽  
Weighted Mean ◽  
Surface Gravity Waves ◽  
Viscosity Term ◽  
Effect Of Surface

Abstract The residual effect of surface gravity waves on mean flows in the upper ocean is investigated using thickness-weighted mean (TWM) theory applied in a vertically Lagrangian and horizontally Eulerian coordinate system. Depth-dependent equations for the conservation of volume, momentum, and energy are derived. These equations allow for (i) finite amplitude fluid motions, (ii) the horizontal divergence of currents, and (iii) a concise treatment of both kinematic and viscous boundary conditions at the sea surface. Under the assumptions of steady and monochromatic waves and a uniform turbulent viscosity, the TWM momentum equations are used to illustrate the pressure- and viscosity-induced momentum fluxes through the surface, which are implicit in previous studies of the wave-induced modification of the classical Ekman spiral problem. The TWM approach clarifies, in particular, the surface momentum flux associated with the so-called virtual wave stress of Longuet-Higgins. Overall, the TWM framework can be regarded as an alternative to the three-dimensional Lagrangian mean framework of Pierson. Moreover, the TWM framework can be used to include the residual effect of surface waves in large-scale circulation models. In specific models that carry the TWM velocity appropriate for advecting tracers as their velocity variable, the turbulent viscosity term should be modified so that the viscosity acts only on the Eulerian mean velocity.

scholarly journals Scattering of surface gravity waves by bottom topography with a current

2007 ◽  
Vol 576 ◽  
pp. 235-264 ◽  
Author(s):  
FABRICE ARDHUIN ◽  
RUDY MAGNE
Keyword(s):  
Gravity Waves ◽  
Bottom Topography ◽  
Wave Spectrum ◽  
Action Spectrum ◽  
Wave Action ◽  
Surface Gravity ◽  
Small Scale ◽  
Surface Gravity Waves ◽  
Reflected Wave ◽  
A Current

A theory is presented that describes the scattering of random surface gravity waves by small-amplitude topography, with horizontal scales of the order of the wavelength, in the presence of an irrotational and almost uniform current. A perturbation expansion of the wave action to order η2 yields an evolution equation for the wave action spectrum, where η = max(h)/H is the small-scale bottom amplitude normalized by the mean water depth. Spectral wave evolution is proportional to the bottom elevation variance at the resonant wavenumbers, representing a Bragg scattering approximation. With a current, scattering results from a direct effect of the bottom topography, and an indirect effect of the bottom through the modulations of the surface current and mean surface elevation. For Froude numbers of the order of 0.6 or less, the bottom topography effects dominate. For all Froude numbers, the reflection coefficients for the wave amplitudes that are inferred from the wave action source term are asymptotically identical, as η goes to zero, to previous theoretical results for monochromatic waves propagating in one dimension over sinusoidal bars. In particular, the frequency of the most reflected wave components is shifted by the current, and wave action conservation results in amplified reflected wave energies for following currents. Application of the theory to waves over current-generated sandwaves suggests that forward scattering can be significant, resulting in a broadening of the directional wave spectrum, while back-scattering should be generally weaker.

scholarly journals Modeling and control of surface gravity waves in a model of a copper converter

2008 ◽  
Vol 32 (9) ◽  
pp. 1696-1710 ◽  
Author(s):  
Eduardo Godoy ◽  
Axel Osses ◽  
Jaime H. Ortega ◽  
Alvaro Valencia
Keyword(s):  
Gravity Waves ◽  
Surface Gravity ◽  
Modeling And Control ◽  
Copper Converter ◽  
Surface Gravity Waves ◽  
And Control

Irrotational, progressive surface gravity waves near the limiting height

1973 ◽  
Vol 29 (3) ◽  
pp. 94-105 ◽  
Author(s):  
Ken Sasaki ◽  
Takashi Murakami
Keyword(s):  
Gravity Waves ◽  
Surface Gravity ◽  
Surface Gravity Waves
Sign in / Sign up

Export Citation Format

Share Document