https://scholars.lib.ntu.edu.tw/handle/123456789/571906
標題: | Frequency shift of near-inertial waves in the South China sea | 作者: | Le Boyer A Alford M.H Pinkel R Hennon T.D YIING-JANG YANG Ko D Nash J. |
關鍵字: | Kinetics; Ocean currents; Tidal power; Doppler shifting; Frequency shift; Frequency spectra; Inertial frequency; Intrinsic frequency; Near-inertial waves; Relative vorticity; Semi-Lagrangian; Kinetic energy; inertia; kinetic energy; mesoscale motion; ocean wave; time dependent behavior; vorticity; wave field; wind forcing; Pacific Ocean; South China Sea | 公開日期: | 2020 | 卷: | 50 | 期: | 5 | 起(迄)頁: | 1121-1135 | 來源出版物: | Journal of Physical Oceanography | 摘要: | Despite sufficient wind forcing, internal waves in the South China Sea do not exhibit the strong near-inertial wave (NIW) peak that is typical in most of the world oceans. Using data from 10 contemporaneous moorings deployed in summer 2011, we show that strong isopycnal vertical tidal displacements transfer most of the near-inertial (NI) kinetic energy (KE) to frequencies higher than the inertial frequency in an Eulerian reference frame. Transforming to an isopycnal-following reference frame increases the KE at NI frequencies, suggesting the presence of NIWs. However, the projection onto a semi-Lagrangian coordinate system still underestimates the expected NI peak. To fully resolve NIWs requires the use of time-dependent vertical wavenumber–frequency spectra because the intrinsic frequency of the NIWs varies substantially, owing to Doppler shifting by lateral mesoscale flows. Here, we show NIW intrinsic frequency variations of ±0.2 cpd within few days, of similar magnitude as the observed variations of relative vorticity associated with the meandering Kuroshio. ? 2020 American Meteorological Society. |
URI: | https://www.scopus.com/inward/record.uri?eid=2-s2.0-85087607908&doi=10.1175%2fJPO-D-19-0103.1&partnerID=40&md5=dc89b82127c72941d2f5c55804456797 https://scholars.lib.ntu.edu.tw/handle/123456789/571906 |
ISSN: | 223670 | DOI: | 10.1175/JPO-D-19-0103.1 |
顯示於: | 海洋研究所 |
在 IR 系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。