Study on the premature separation of western boundary current and formation of eastward jet

• Project/Area Number: 21540447
• 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: Hokkaido University
• Principal Investigator: KUBOKAWA Atsushi 北海道大学, 大学院・地球環境科学研究院, 教授 (00178039)
• Co-Investigator(Kenkyū-buntansha): MIZUTA Genta 北海道大学, 大学院・地球環境科学研究院, 助教 (30301948)
• Project Period (FY): 2009 – 2012
• Project Status: Completed (Fiscal Year 2012)
• Budget Amount: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000); Fiscal Year 2012: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2011: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2010: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2009: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
• Keywords: 海洋循環 / 西岸境界流 / 離岸 / 東向ジェット

Research Abstract

Numerical experiments using a 2-layer quasi-geostrophic mode and a primitive equation model were carried out to study the dynamics of oceanic western boundary current separation and formation of the eastward extension jet. There are two types of stable solutions; one of them is the solution in which the eastward jet is formed along the subtropical/subpolar gyre boundary and the other is the prematurely separated jet solution in which the western boundary current separation occurs far upstream of the gyre boundary. It was found that the latitude of the prematurely separated jet was almost independent of model parameters including nonlinearity. Dependence of the jet latitude on the meridional distribution of the wind forcing was investigated and the mechanism determining the jet latitude was discussed.

Research Products

• [Journal Article] Role of the Rossby waves in the Broadening of an Eastward Jet (2012)
  • Author(s): Mizuta, G
  • Journal Title: Journal of Physical Oceanography Volume: Vol. 42 Pages: 476-494
  • NAID: 120004608961
  • Peer Reviewed
• [Journal Article] Role of the Rossby waves in the Broadening of an Eastward Jet (2012)
  • Author(s): Mizuta, G.
  • Journal Title: Journal of Physical Oceanography Volume: 42 Issue: 3 Pages: 476-494
  • DOI: 10.1175/jpo-d-11-070.1
  • NAID: 120004608961
  • Peer Reviewed
• [Journal Article] 沿岸・陸棚スケールと大洋スケールの海洋前線の違い
  • Author(s): 久保川厚
  • Journal Title: 沿岸海洋研究 Volume: 50巻 Pages: 87-94
  • NAID: 130007797380
  • Peer Reviewed
• [Presentation] 表層に振動を与えた場合の波による深層平均流形成 (2013)
  • Author(s): 水田元太、増田章
  • Organizer: 2013年度日本海洋学会春季大会
  • Place of Presentation: 東京海洋大学品川キャンパス(東京都)
  • Year and Date: 2013-03-24
• [Presentation] 西岸境界流の東向き続流ジェットの緯度について(続) (2013)
  • Author(s): 陶泰典・久保川厚
  • Organizer: 2013 年度日本海洋学会春季大会
  • Place of Presentation: 東京海洋大学品川キャンパス(東京都)
  • Year and Date: 2013-03-22
• [Presentation] 沿岸・陸棚スケールと大洋スケールの海洋前線の違い (2012)
  • Author(s): 久保川厚
  • Organizer: 2012年度日本海洋学会春季大会沿岸海洋シンポジウム
  • Place of Presentation: 筑波大学(つくば市)
  • Year and Date: 2012-03-26
• [Presentation] 沿岸・陸棚スケールと大洋スケールの海洋前線の違い (2012)
  • Author(s): 久保川厚
  • Organizer: 日本海洋学会春季大会シンポジウム
  • Place of Presentation: 筑波大学(つくば市)
  • Year and Date: 2012-03-26
• [Presentation] Latitude of eastward jet prematurely separated from the western boundary in a two-layer QG model (2012)
  • Author(s): Sue, Y. and Kubokawa, A
  • Organizer: 2012AGU Ocean Science Meeting, Salt Palace Convention Center
  • Place of Presentation: Utah, USA
  • Year and Date: 2012-02-20
• [Presentation] Latitude of eastward jet prematurely separated from the western boundary in a two-layer QG model (2012)
  • Author(s): Sue, Y., Kubokawa, A.
  • Organizer: 2012 AGU Ocean Science Meeting
  • Place of Presentation: Salt Palace Convention Centet (USA)
  • Year and Date: 2012-02-20
• [Presentation] 西岸境界流の東向き続流ジェットの緯度について (2011)
  • Author(s): 陶泰典・久保川厚
  • Organizer: 2011年度日本海洋学会秋季大会
  • Place of Presentation: 九州大学筑紫キャンパス(春日市)
  • Year and Date: 2011-09-29
• [Presentation] 西岸境界流の東向き続流ジェットの緯度について (2011)
  • Author(s): 陶泰典・久保川厚
  • Organizer: 日本海洋学会秋季大会
  • Place of Presentation: 九州大学(春日市)
  • Year and Date: 2011-09-29
• [Presentation] IDO-CF法の準地衡流モデルへの適用-高精度モデルにおける西岸境界流の離岸 (2011)
  • Author(s): 陶泰典・久保川厚
  • Organizer: 2011年度日本海洋学会春季大会
• [Presentation] 再循環を伴う東向きジェットの西岸域からの侵入 (2010)
  • Author(s): 久保川厚
  • Organizer: 2010年度日本海洋学会秋季大会
  • Place of Presentation: 東京農業大学オホーツクキャンパス(網走市)
  • Year and Date: 2010-09-08
• [Presentation] 再循環を伴う東向きジェットの西岸域からの侵入 (2010)
  • Author(s): 久保川厚
  • Organizer: 2010年度日本海洋学会秋季大会
  • Place of Presentation: 東京農業大学(北海道、網走市)
  • Year and Date: 2010-09-08
• [Presentation] Radiation processes of the Rossby waves from a recirculation gyre and their effects on mean flows (2010)
  • Author(s): Mizuta, G
  • Organizer: European Geosciences Union, General Assembly 2010
  • Place of Presentation: Austria Center Vienna, Austria
  • Year and Date: 2010-05-04
• [Presentation] Radiation processes of the Rossby waves from a recirculation gyre and their effects on mean flows (2010)
  • Author(s): 水田元太
  • Organizer: European Geosciences Union General Assembly 2010
  • Place of Presentation: Austria Center Vienna
  • Year and Date: 2010-05-04
• [Presentation] 2.5層通気水温躍層の周期的風応力強制への応答
  • Author(s): 久保川厚
  • Organizer: 2012年度日本海洋学会秋季大会
  • Place of Presentation: 静岡市 東海大学
• [Presentation] 西岸境界流の東向き続流ジェットの緯度について
  • Author(s): 陶泰典、久保川厚
  • Organizer: 2013年度日本海洋学会春季大会
  • Place of Presentation: 東京都 東京海洋大学
• [Presentation] 表層に振動を与えた場合の波による深層平均流形成
  • Author(s): 水田元太、増田章
  • Organizer: 2013年度日本海洋学会春季大会
  • Place of Presentation: 東京都 東京海洋大学