Observations of near bed turbulent production and dissipation on the inner shelf at Pt. Sal
Abstract
Waves, temperature profiles and current profiles were measured for two months along the inner shelf of California to quantify internal wave activity and bottom boundary layer turbulence. Six moorings were deployed in two transects, north and south of Point Sal, CA, along the 20, 35 and 50 m isobaths. The moorings along each transect were separated by about 20 km in the alongshore. Internal wave activity was monitored using a vertical array of temperature sensors (SBE56) sampled continuously at 1 Hz with 3-m spacing at all six moorings. Bottom boundary layer processes were observed with two U.S. Naval Research Laboratory (NRL) integrated quadpods, deployed at the 35-m isobath (NRL35N and NRL35S). The analysis presented here focuses primarily on measurements at NRL35N, where current profiles were measured from 0 - 3 meters above the bed (mab) using Nortek AquadoppHR Profilers, in 20-minute bursts every half hour (2 Hz, 0.05 m bin size). The rate of production and dissipation of turbulent kinetic energy were estimated using velocities recorded by a vertical stack of four Nortek Vector acoustic Doppler velocimeters (ADVs), located from 0.7 - 3.0 mab. The effect of internal waves on the turbulent bottom boundary layer are explored. In addition, we examine the evolution of turbulent eddy viscosity during the intense internal wave events.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFMOS13B..05M
- Keywords:
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- 4217 Coastal processes;
- OCEANOGRAPHY: GENERAL