The Windwave and Turbulence Observation Program (WAVTOP). The Measurement of Parameters Controlling Downward Mixing of Oil from the Sea Surface.
NAVAL UNDERWATER SYSTEMS CENTER NEWPORT RI
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The wave and turbulence observation program WAVTOP has developed instrumentation and techniques to gather field data of the wind-generated motions in the upper ocean. The sensor package BLT includes small fast-response impellers and a capacitance wave staff system to measure particle velocity components and free surface elevation to determine shear, kinetic and potential energy content, and Reynolds stresses in the upper 5-10m. The battery-powered recording system utilizes a microprocessor digitizer programmable for data sampling. Preliminary measurements were made with the BLT mounted on the AESOP Stable Spar Buoy and from a fixed boom on Gould Island. Results portray kinetic energy attenuating exponential with depth and correlating with the local wind speed. The vertically integrating energy appears to correlate with the cube of the wind speed with a 15-20 min time lag. Auto-spectra of the velocity data display narrow peaks demonstrating the monochromaticity of small wind waves. The spectra verify the attenuation of the wave energy with depth. Higher frequency wave number energy persists at deeper depths suggesting the presence of ambient turbulence. Reynolds stresses show fluctuations with time but display downward momentum flux and range from 1-2 dynecm2 for winds from 4-5 msec.
- Physical and Dynamic Oceanography