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Recent measurements at a cabled sea-floor node in 15 meters of water off the coast of New Jersey suggest that Langmuir supercells, Langmuir circulations that achieve vertical scales equal to the water depth under extended storms, are an important mechanism for major sediment resuspension events on the extensive shallow shelves off the eastern U.S. coast. Because sediment resuspension is a prelude to transport, supercell events are a necessary condition for major sediment transport. Such events may also contribute to shelf-sea exchange and to offshore gradation of benthic community structure in shallow seas., In wind- and wave-driven surface layers of lakes and oceans, Langmuir circulations (LC) are parallel counterrotating vortices oriented roughly downwind, with maximum downwind velocities at the surface convergences between vortex [...]

A theoretical response function of full-depth Langmuir supercells (LSC) and unstable convection turbulent flows is determined for vertical velocity variance from slant beam measurements of a standard ADCP (acoustic Doppler current profiler). Results indicate that the most accurate estimate of vertical velocity variance using the ADCP is the larger of the two pair estimates, and not the usual 4-beam estimate.