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 surface stress is investigated using a three-dimensional time-dependant ocean circulation model. The 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.
In the ocean environment, the physical processes governing the water column are influenced by atmospheric flow, currents, surface waves, tides and their mutual interactions. A better understanding of the physical process is essential for studying the chemical and biological processes in scientific and practical applications, such as beach erosion, upwelling, storm surges and transport of various materials. Compared to high cost of field measurements, the numerical model for solving time dependent flows is both effective and economical. Extensive and intensive studies of ocean modeling have been undertaken in last a couple of decades. Ocean models have become an important tool for understanding the seasonal ocean circulation and thermal structure, and for establishing a nowcast system for regional seas. The South China Sea (SCS) has complex bottom topography and open boundaries. Metzger and Hurlburt (1996) first applied a layered model to the SCS and compared upper layer currents and sea levels of the model with the observed data. Recently, Cai et al. (2002) developed a coupled singlelayer/two-layer model to study the upper circulation.
