Journal of Oceanography

, Volume 49, Issue 6, pp 667–682 | Cite as

TheKyucho in Sukumo Bay induced by Kuroshio warm filament intrusion

  • Hideki Akiyama
  • Sei-ichi Saitoh


Surface temperature data obtained in and out of the bay all year round from March 1990 through February 1991, except from July through October 1990 were analyzed to investigate seasonal variability of theKyucho in Sukumo Bay, southwest of Shikoku, Japan. TheKyucho periodically occurs in the bay during both the warming period of March through June and the cooding period of November through February. The onset period of theKyucho is 8–15 days during the warming period and 4–14 days during the cooling period, giving an average of about 10 and 8 days, respectively. The position of the Kuroshio axis offshore in the south of Cape Ashizuri-misaki is a significant factor with theKyucho in the bay. Thermal infrared images taken by the NOAA-11 in the sea off east of Kyushu were also analyzed during the two observation periods. It is clearly found that a warm filament derived from the Kuroshio (KWF) advects northeast to Cape Ashizurimisaki along the Kuroshio, then encounters the southwest coast of Shikoku, followed by inducing theKyucho in the bay by the warm water intrusion. The alongshelf dimension of the KWFs is approximately 50–100 km, and the cross-shelf distance from the western edge of the KWFs to that of the body of the east Kuroshio is about 30–50 km. The KWF sometimes closely approaches to the east coast of Kyushu. An onshore meander of the Kuroshio front around Cape Toimisaki might grow into a KWF in the sea off east of Kyushu.


Japan Surface Temperature Temperature Data East Coast Warm Water 
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Copyright information

© Journal of the Oceanographic Society of Japan 1993

Authors and Affiliations

  • Hideki Akiyama
    • 1
  • Sei-ichi Saitoh
    • 2
  1. 1.Department of Civil and Ocean EngineeringEhime UniversityMatsuyamaJapan
  2. 2.Meteorological Information CenterJapan Weather AssociationTokyoJapan

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