Journal cover Journal topic
Ocean Science An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 2.864
IF2.864
IF 5-year value: 3.337
IF 5-year
3.337
CiteScore value: 4.5
CiteScore
4.5
SNIP value: 1.259
SNIP1.259
IPP value: 3.07
IPP3.07
SJR value: 1.326
SJR1.326
Scimago H <br class='widget-line-break'>index value: 52
Scimago H
index
52
h5-index value: 30
h5-index30
Preprints
https://doi.org/10.5194/osd-11-1871-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/osd-11-1871-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.

  22 Jul 2014

22 Jul 2014

Review status
This preprint was under review for the journal OS but the revision was not accepted.

Flow separation of intermediate water in the lees of sills off Taiwan from seismic observations

Q. S. Tang1, L. T. Sun1, J. B. Li2, and C. S. Liu3 Q. S. Tang et al.
  • 1Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
  • 2Key Laboratory of Submarine Geoscience, Second Institute of Oceanography, State Oceanic Administration, Hangzhou, China
  • 3Institute of Oceanography, National Taiwan University, Taipei, Taiwan

Abstract. Flow separation can occur when a stratified flow passes over an obstacle. Previous studies concerning flow separation are mostly observed in the shallow water regions, e.g., fjord, driven by tidal flows. In this study, a novel view of flow separations of the intermediate water over the Hengchun Ridge and Ryukyu Arc off Taiwan is firstly reported using seismic oceanography by reprocessing the seismic data from two cruises 97306 and EW9509 in 2001 and 1995, respectively. Both seismic images show that water masses are separated by internal interfaces detached from sill crests. Over the Hengchun Ridge, it was previously considered that the intermediate water flowed out of the South China Sea into the Hengchun Trough. Flow separation occurred at the lee-side of the ridge forming a continuous interface > 15 km between the intermediate and deep water at 900 m depth. This interface suggests that (1) mean flow of the intermediate water always flowed eastward and (2) no lee wave was generated or radiated even during a spring ebb tide. Near the East Taiwan Channel, the only major passage of the Kuroshio into the Okinawa Trough, flow separation occurred when the Kuroshio intermediate water flowed over the Ryukyu Arc at 500 m depth. The separation interface is nearly horizontal and extends > 25 km from the sill break to the trough. Parameter estimations and morphologic comparisons show that both separation cases are neither boundary-layer separation nor post-wave separation. Model data from OFES (Ocean General Circulation Model For the Earth Simulator) reveal dense pools existing downstream of the sill crests. We propose that a density-forced flow separation mechanism could be responsible for the observed flow separations and absence of lee waves in this study.

Q. S. Tang et al.

Interactive discussion

Status: closed
Status: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement

Interactive discussion

Status: closed
Status: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement

Q. S. Tang et al.

Q. S. Tang et al.

Viewed

Total article views: 1,256 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
733 448 75 1,256 64 88
  • HTML: 733
  • PDF: 448
  • XML: 75
  • Total: 1,256
  • BibTeX: 64
  • EndNote: 88
Views and downloads (calculated since 22 Jul 2014)
Cumulative views and downloads (calculated since 22 Jul 2014)

Cited

Saved

Discussed

No discussed metrics found.
Latest update: 03 Dec 2020
Publications Copernicus
Download
Citation