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Journal of Oceanography

, Volume 52, Issue 4, pp 491–507 | Cite as

Process of the Tsushima Current formation revealed by ADCP measurements in summer

  • Osamu Katoh
  • Kazuyuki Teshima
  • Osamu Abe
  • Hitoshi Fujita
  • Kuniaki Miyaji
  • Kenji Morinaga
  • Norihisa Nakagawa
Article

Abstract

In order to clarify detailed current structures over the continental shelf margin in the East China Sea, ADCP measurements were carried out in summers in 1991 and 1994 by the quadrireciprocal method (Katoh, 1988) for removing diurnal and semidiurnal tidal flows from observed flows, together with CTD measurements. We discussed the process of the Tsushima Current formation in the East China Sea. The Tsushima Current with a volume transport of 2 Sv (1 Sv=106 m3s−1) was found north of 31°N. A current with a volume transport of 0.4 Sv was clearly found along the 100 m isobath. Between the Kuroshio and the current along the 100 m isobath, southeastward component of velocity was dominant compared to northwestward one. Four eastward to southeastward currents were found over the sea bed shallower than 90 m depth. Total volume transport of these four currents was 1 Sv, and they seemed to be originated from the Taiwan Strait. Intrusion of offshore water into the inner shelf northwest of Amami Oshima was estimated to have a volume transport of 0.6 Sv. It is concluded that the Tsushima Current is the confluence of these currents over the continental shelf margin with the offshore water intruding northwest of Amami Oshima.

Keywords

Continental Shelf Current Formation Volume Transport Tidal Flow Current Structure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Journal of the Oceanographic Society of Japan 1996

Authors and Affiliations

  • Osamu Katoh
    • 1
  • Kazuyuki Teshima
    • 1
  • Osamu Abe
    • 1
  • Hitoshi Fujita
    • 1
  • Kuniaki Miyaji
    • 2
  • Kenji Morinaga
    • 1
  • Norihisa Nakagawa
    • 1
  1. 1.Seikai National Fisheries Research InstituteNagasakiJapan
  2. 2.National Research Institute of Fisheries ScienceYokohamaJapan

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