Wave Induced Turbulence in the Upper Ocean
(W. Kendall Melville, Scripps Institute of Oceanography)
Submarine research.
Langmuir circulations. Wave breaking limits height of surface waves, dissipates surface wave energy and transfers momentum from waves to currents, and is a source of vorticity. It exhibits translational phenomenon, enhances heat and gas transfer through turbulence and bubbles, is a major source of sound in the ocean, and a source of active/passive microwave signatures. Breaking at larger scales may result from dispersive focusing, geometric focusing, wave-wave and wave-current interactions without wind forcing being directly involved. Work done against buoyancy in entraining air comprises about 50% of energy from the wave-field. Air entrainment and mixing: breaking waves entrain air as the surface water is rapidly mixed down to depths comparable to wave height- subsequently, slower processes mix the air-water mixture down to greater depths- the smallest bubbles are tracer for fluid originally on surface. Entrained air breaks up into bubbles which may enhance gas transfer. Individual bubbles and clouds may radiate sound as they relax to equilibrium configurations- invert for air-sea fluxes single bubble; ocean optics- scattering, reflectance, attenuate; strong attenuation of light and sound waves under a moving surface