Wind Wave Effects on Hydrodynamic Modeling of Ocean Circulation in the South China Sea

Wind, wave and current interactions control the boundary fluxes, momentum and energy exchange between the atmosphere and the ocean, and within the water column. The wind wave effect on the circulation is investigated in a three- dimensional time-dependant ocean circulation model. This POM (Princeton Ocean Model) based model is implemented with realistic coastlines in South China Sea and emphasizes the simulation of physical parameters in the water column. Taking account of the wind waves, an increase in air-sea drag coefficient, reflecting an enhanced sea surface roughness due to increased wave heights, is shown to improve the simulated surface current and the sea surface elevation. It is also found that developing waves with smaller peak periods influenced the surface circulation more significantly. The inclu- sion of the wind wave parameterization also affects the current near the seabed in the shallow water. The model is validated against current, temperature and salinity data measured in the Asian Seas International Acoustics Experiment (ASIAEX). The simulation results in the period of April - May 2001 show that wave-induced surface stress increases the magnitude of currents both at the surface and near the seabed. On the other hand, wave-induced bottom stress retards the near bottom currents in shallow water. Therefore the net effect of wind waves on circulation depends on the significance of current and elevation changes due to wind waves through both the surface and the bottom.

[1]  O. Madsen,et al.  Combined wave and current interaction with a rough bottom , 1979 .

[2]  H. Charnock.  Wind stress on a water surface , 1955 .

[3]  A. M. Davies,et al.  Modelling of turbulent mixing at the shelf edge , 2000 .

[4]  N. Booij,et al.  A third-generation wave model for coastal regions-1 , 1999 .

[5]  R. Long,et al.  Array measurements of atmospheric pressure fluctuations above surface gravity waves , 1981, Journal of Fluid Mechanics.

[6]  M. Banner,et al.  Modeling Wave-Enhanced Turbulence in the Ocean Surface Layer , 1994 .

[7]  O. Madsen.  SPECTRAL WAVE-CURRENT BOTTOM BOUNDARY LAYER FLOWS , 1995 .

[8]  H. Graber,et al.  On the wave age dependence of wind stress over pure wind seas , 2003 .

[9]  P. Chu,et al.  Dynamical Mechanisms for the South China Sea Seasonal Circulation and Thermohaline Variabilities , 1999 .

[10]  F. Qiao,et al.  Wave‐induced mixing in the upper ocean: Distribution and application to a global ocean circulation model , 2004 .

[11]  C. Fairall,et al.  Wind Stress Vector over Ocean Waves , 2003 .

[12]  Kevin E. Trenberth,et al.  Recent Observed Interdecadal Climate Changes in the Northern Hemisphere , 1990 .

[13]  R. Signell,et al.  Effect of wave-enhanced bottom friction on storm-driven circulation in Massachusetts Bay , 1997 .

[14]  A. Blumberg,et al.  Wave Breaking and Ocean Surface Layer Thermal Response , 2004 .

[15]  O. Madsen,et al.  The continental-shelf bottom boundary layer , 1986 .

[16]  S. Glenn,et al.  Bottom Stress Estimates and their Prediction on the Northern California Continental Shelf during CODE-1: The Importance of Wave-Current Interaction , 1985 .

[17]  H. Sverdrup,et al.  The Pacific Ocean , 2017 .

[18]  Jilan Su,et al.  The numerical study of the South China Sea upper circulation characteristics and its dynamic mechanism, in winter , 2002 .

[19]  S. A. Sannasiraj,et al.  Hydrodynamic model with wave-current interaction in coastal regions , 2004 .

[20]  Fei Liu,et al.  Model Description and Validation , 2006 .

[21]  H. K. Johnson,et al.  Effects of Water Waves on Wind Shear Stress for Current Modeling , 1992 .

[22]  H. Hurlburt,et al.  Coupled dynamics of the South China Sea, the Sulu Sea, and the Pacific Ocean , 1996 .

[23]  C. Sherwood,et al.  Estimation of stress and bed roughness during storms on the Northern California Shelf , 1992 .

[24]  S. Massel,et al.  Wave-induced set-up and flow over shoals and coral reefs. Part 1. A simplified bottom geometry case , 2001 .

[25]  P. Janssen.  Quasi-linear Theory of Wind-Wave Generation Applied to Wave Forecasting , 1991 .

[26]  Ivar G. Jonsson,et al.  Bed friction and dissipation in a combined current and wave motion , 1985 .

[27]  I. Moon.  Impact of a coupled ocean wave–tide–circulation system on coastal modeling , 2005 .

[28]  S. Hasselmann,et al.  Computations and Parameterizations of the Nonlinear Energy Transfer in a Gravity-Wave Spectrum. Part I: A New Method for Efficient Computations of the Exact Nonlinear Transfer Integral , 1985 .

[29]  E. Chan,et al.  Modeling of the Turbulence in the Water Column under Breaking Wind Waves , 2003 .

[30]  Sol Hellerman,et al.  Normal Monthly Wind Stress Over the World Ocean with Error Estimates , 1983 .

[31]  Nicolas Reul,et al.  On the limiting aerodynamic roughness of the ocean in very strong winds , 2004 .

[32]  G. Mellor.  USERS GUIDE for A THREE-DIMENSIONAL, PRIMITIVE EQUATION, NUMERICAL OCEAN MODEL , 1998 .

[33]  J. Bye,et al.  Drag coefficient reduction at very high wind speeds , 2006 .

[34]  Lian Xie,et al.  A numerical study of wave‐current interaction through surface and bottom stresses: Wind‐driven circulation in the South Atlantic Bight under uniform winds , 2001 .

[35]  M. Powell,et al.  Reduced drag coefficient for high wind speeds in tropical cyclones , 2003, Nature.

[36]  M. Donelan,et al.  On the Dependence of Sea Surface Roughness on Wave Development , 1993 .

[37]  Y. S. Li,et al.  The dynamic coupling of a third-generation wave model and a 3D hydrodynamic model through boundary layers , 1997 .