Open AccessVelocity Structure of Internal Tide Beams Emanating from Kaena Ridge, Hawaii
Author(s) -
Andy Pickering,
Matthew H. Alford
Publication year - 2012
Publication title -
journal of physical oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.706
H-Index - 143
eISSN - 1520-0485
pISSN - 0022-3670
DOI - 10.1175/jpo-d-12-018.1
Subject(s) - geology , internal tide , ridge , crest , geodesy , internal wave , acoustic doppler current profiler , transect , oceanography , current (fluid) , seismology , paleontology , optics , physics
Observations are reported of the semidiurnal (M2) internal tide across Kaena Ridge, Hawaii. Horizontal velocity in the upper 1000–1500 m was measured during eleven ~240-km-long shipboard acoustic Doppler current profiler (ADCP) transects across the ridge, made over the course of several months. The M2 motions are isolated by means of harmonic analysis and compared to numerical simulations using the Princeton Ocean Model (POM). The depth coverage of the measurements is about 3 times greater than similar past studies, offering a substantially richer view of the internal tide beams. Sloping features are seen extending upward north and south from the ridge and then downward from the surface reflection about ±40 km from the ridge crest, closely matching theoretical M2 ray paths and the model predictions.