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Journal of Oceanography

, Volume 55, Issue 2, pp 207–216 | Cite as

Direct Measurements of Deep Currents in the Northern Japan Sea

  • Masaki Takematsu
  • Zentaro Nagano
  • Alexander G. Ostrovski
  • Kuu Kim
  • Yuri Volkov
Article

Abstract

Long-term current measurements by means of subsurface moorings were made for the first time at seven sites in the Japan Basin, the northern part of the Japan Sea. The objective was to directly explore the velocity field in the highly homogeneous deep water mass (the Japan Sea Proper Water) that occupies depths below 500 m. On each mooring three current meters were equipped at an approximately equal distance below about 1000 m depth. Duration of the measurements was 1 to 3 years depending on specific site. This paper describes the basic data set from the moored measurements. It is found that the deep water of the Japan Basin is very energetic with eddies and vertically coherent currents of the order of 0.1 m/s. Surprisingly, the currents and eddies exhibit strong seasonal dependence even in the deepest layers of the Basin. The observed new current features are discussed in comparison with conventional deep circulation pictures derived from hydrographic data.

Japan Basin subsurface moorings strong deep circulation eddy-like currents seasonal changes Liman Current 

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Copyright information

© The Oceanographic Society of Japan 1999

Authors and Affiliations

  • Masaki Takematsu
    • 1
  • Zentaro Nagano
    • 1
  • Alexander G. Ostrovski
    • 1
  • Kuu Kim
    • 2
  • Yuri Volkov
    • 3
  1. 1.Research Institute for Applied MechanicsKyushu UniversityKasugaJapan
  2. 2.Department of Oceanography and Research Institute of OceanographySeoul National UniversitySeoulKorea
  3. 3.Far Eastern Regional Hydrometeorological Research InstituteVladivostokRussia

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