Observation of Near-Bottom Current on the Continental Shelf Off Sanriku
We measured current velocity sections including near-bottom current within 10-m range above the bottom about 100-m depth off Otsuchi Bay with using a subsurface towfish mounting an acoustic Doppler current profiler. Four-time navigating observations showed the transition of the current distribution through flood tide. The near-bottom current has smaller spatial scales than the upper currents and its temporal variation is not in phase with tidal current which has a baroclinic structure in the upper layers. We did not find organized near-bottom current widely perhaps due to absence of the bottom boundary layer.
KeywordsNear-bottom current Towed acoustic doppler current profiler Continental shelf Otsuchi bay
The authors would like to thank Captain M. Hirano and his crew of R/V Yayoi. The authors would also thank the Tohoku Ecosystem-Associated Marine Sciences for providing financial support to this project.
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