Mechanisms governing the winter Kuroshio path destabilization Phenomenon in the East China Sea and its interannual amplitude modulation

• Project/Area Number: 20540428
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: Kagoshima University
• Principal Investigator: NAKAMURA Hirohiko Kagoshima University, 水産学部, 准教授 (50284914)
• Co-Investigator(Kenkyū-buntansha): NISHINA Ayako 鹿児島大学, 水産学部, 助教 (80311885) ; YAMASHIERO Toru 鹿児島大学, 理工学研究科, 教授 (20158174)
• Project Period (FY): 2008 – 2010
• Project Status: Completed (Fiscal Year 2010)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2010: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2009: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2008: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
• Keywords: 黒潮流路 / 沖縄トラフ / 不安定現象 / 冬季季節風 / 人工衛星海面高度計 / 海洋大循環モデル / 黒潮小蛇行 / 黒潮 / 季節変動 / 力学系 / 季節風 / 湧昇流 / 海洋観測

Research Abstract

The present study investigated the mechanism responsible for the winter Kuroshio path destabilization phenomenon in the northern Okinawa Trough. Theoretical consideration and a numerical model revealed the following mechanism : The winter northerly wind over the Okinawa Trough blows against the Kuroshio, generating upwelling within the inshore side of the Kuroshio. This winter upwelling makes the mean Kuroshio path separate from the continental slope in the northern Okinawa Trough so that baroclinic instability destabilizes the Kuroshio path. Furthermore, a new time series of satellite-derived geostrophic velocity distribution was developed in a section across the Kuroshio in the period 1992-2010. This dataset indicated that the interannual amplitude modulation of the seasonality is mainly caused by interannual variation in the winter northerly wind over the northern Okinawa Trough.

Research Products

• [Journal Article] 混合期における鹿児島湾への外洋水の流入特性について (2011)
  • Author(s): 高田雅司・山城徹・坂本一義・中村啓彦・内山正樹・福田隆二・仁科文子
  • Journal Title: 土木学会論文集B3(海洋開発) Volume: 67(印刷中で不明)
  • NAID: 130004558491
  • Peer Reviewed
• [Journal Article] Seasonality of the Kuroshio path destabilization phenomenon in the Okinawa Trough : A numerical study of its mechanism (2010)
  • Author(s): Nakamura, H., M.Nonaka, H.Sasaki
  • Journal Title: J.Phys.Oceanogra. 40
  • Peer Reviewed
• [Journal Article] Seasonality of the Kuroshio path destabilization phenomenon in the Okinawa Trough : A numerical study of its mechanism (2010)
  • Author(s): Nakamura, H., M.Nonaka, H.Sasaki
  • Journal Title: Journal of Physical Oceanography 40 Pages: 530-550
  • Peer Reviewed
• [Journal Article] Manifestation of the Pacific Decadal Oscillation in the Kuroshio (2009)
  • Author(s): Andres, M., J.-H. Park, M.Wimbush, X.-H. Zhu, H.Nakamura, K.Kim, K.-I.Chang
  • Journal Title: Geophys.Res.Lett.
  • Peer Reviewed
• [Presentation] 東シナ海における中国沿岸起源の流れ藻の輸送過程 (2011)
  • Author(s): 児玉琢也・中村啓彦・仁科文子
  • Organizer: 2011年度日本海洋学会春季大会
  • Place of Presentation: 東京大学大気海洋研究所(千葉県柏市)
  • Year and Date: 2011-03-23
• [Presentation] 沖縄トラフ中深層の水塊分布 (2011)
  • Author(s): 西元源・仁科文子・中村啓彦
  • Organizer: 2011年度日本海洋学会春季大会
  • Place of Presentation: 東京大学大気海洋研究所(千葉県柏市)
  • Year and Date: 2011-03-23
• [Presentation] 北部沖縄トラフの黒潮流路変動-係留観測データと衛星海面高度計データの比較- (2010)
  • Author(s): 中村啓彦, 仁科文子, 山城徹, 田畑光太郎
  • Organizer: 日本海洋学会秋季大会
  • Place of Presentation: 東京都(東京農業大学生物産業学部)
  • Year and Date: 2010-09-08
• [Presentation] 北部沖縄トラフの黒潮流路変動-係留観測データと衛星海面高度計データの比較- (2010)
  • Author(s): 中村啓彦・仁科文子・山城徹・田畑光太郎
  • Organizer: 2010年度日本海洋学会秋季大会
  • Place of Presentation: 東京農業大学生物産業学部(北海道網走市)の
  • Year and Date: 2010-09-08
• [Presentation] Formation mechanism of the Kuroshio small meander off the southeastern coast of Kyushu : Stochastic resonance on the seasonal cycle (2010)
  • Author(s): 中村啓彦, 仁科文子, 山城徹
  • Organizer: the 2010 Ocean Sciences Meeting
  • Place of Presentation: American Geophysical Union, USA (Oregon Convention Center)
  • Year and Date: 2010-02-23
• [Presentation] Formation mechanism of the Kuroshio small meander off the southeastern coast of Kyushu : Stochastic resonance on the seasonal cycle (2010)
  • Author(s): 中村啓彦, 仁科文子, 山城徹
  • Organizer: the 2010 Ocean Sciences Meeting, American Geophysical Union
  • Place of Presentation: Portland, Oregon, at the Oregon Convention Center
  • Year and Date: 2010-02-23
• [Presentation] 黒潮小蛇行の発生頻度の季節的偏り (2009)
  • Author(s): 中村啓彦, 仁科文子, 山城徹, 古川洋一郎
  • Organizer: 日本海洋学会秋季大会
  • Place of Presentation: 京都府(京都大学)
  • Year and Date: 2009-09-27
• [Presentation] 北部沖縄トラフにおける表層流速分布の季節変動特性 (2009)
  • Author(s): 田畑光太郎, 中村啓彦, 仁科文子
  • Organizer: 日本海洋学会秋季大会
  • Place of Presentation: 京都府(京都大学)
  • Year and Date: 2009-09-27
• [Presentation] 黒潮小蛇行の発生頻度の季節的偏り (2009)
  • Author(s): 中村啓彦, 仁科文子, 山城徹, 古川洋一郎
  • Organizer: 日本海洋学会秋季大会
  • Place of Presentation: 京都大学
  • Year and Date: 2009-09-27
• [Presentation] 北部沖縄トラフにおける表層流速分布の季節変動特性 (2009)
  • Author(s): 田畑光太郎, 中村啓彦, 仁科文子
  • Organizer: 日本海洋学会秋季大会
  • Place of Presentation: 京都大学
  • Year and Date: 2009-09-27
• [Presentation] Seasonality of the Kuroshio path destabilization in the Okinawa Trough (2008)
  • Author(s): 中村啓彦, 野中正見, 佐々木英治
  • Organizer: OFES International Workshop
  • Place of Presentation: 神奈川県(海洋開発研究機構/横浜研究所)
  • Year and Date: 2008-08-25
• [Presentation] Seasonality of the Kuroshio path destabilization in the Okinawa Trough (2008)
  • Author(s): 中村啓彦, 野中正見 佐々木英治
  • Organizer: OFES International Workshop
  • Place of Presentation: 海洋開発研究機構横浜研究所
  • Year and Date: 2008-08-25
• [Remarks] ホームページ等
  • URL: http://www.fish.kagoshima-u.ac.jp/fish/academic/nh/homepage/kenkyu%20katudou.html