• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

Study of decadal to multi-decadal variability in ocean by using 4-dimensional variational data assimilation method

Research Project

Project/Area Number 25800269
Research Category

Grant-in-Aid for Young Scientists (B)

Allocation TypeMulti-year Fund
Research Field Meteorology/Physical oceanography/Hydrology
Research InstitutionJapan Agency for Marine-Earth Science and Technology

Principal Investigator

OSAFUNE Satoshi  国立研究開発法人海洋研究開発機構, 地球環境観測研究開発センター, 技術研究員 (50638723)

Research Collaborator MASUDA Shuhei  
SUGIURA Nozomi  
DOI Toshimasa  
Project Period (FY) 2013-04-01 – 2016-03-31
Project Status Completed (Fiscal Year 2015)
Budget Amount *help
¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000)
Fiscal Year 2015: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
Fiscal Year 2014: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Fiscal Year 2013: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
Keywords北太平洋 / 長期変動 / データ同化 / 太平洋十年規模振動 / 潮汐18.6年振動 / 気候変動 / 海面水温 / 長周期変動 / 20年変動 / 潮汐混合
Outline of Final Research Achievements

By using a state-of-the-art four-dimensional variational data assimilation system, and a long-term ocean state estimation data set produced by the system, I investigated long-term ocean variability in the mid-to-high-latitude North Pacific, its underlying mechanisms, and its influence on climate. I evaluated the applicability of the data set for climate research, and suggested that the subsurface signal of the Pacific Decadal Oscillation (PDO) is related to the variation in formation of mode waters. In addition, I conducted a comparative numerical experiment using the system, and showed that the 18.6-year modulation of the localized strong tidal mixing can significantly contribute to the sea surface temperature anomalies related to PDO. These results leads to better understanding of the importance of the mid-to-high-latitude ocean in climate system.

Report

(4 results)
  • 2015 Annual Research Report   Final Research Report ( PDF )
  • 2014 Research-status Report
  • 2013 Research-status Report
  • Research Products

    (8 results)

All 2016 2015 2014 Other

All Journal Article (2 results) (of which Peer Reviewed: 2 results,  Acknowledgement Compliant: 2 results) Presentation (5 results) (of which Int'l Joint Research: 1 results,  Invited: 1 results) Remarks (1 results)

  • [Journal Article] Evaluation of the applicability of the Estimated State of the Global Ocean for Climate Research (ESTOC) data set2015

    • Author(s)
      S. Osafune, S. Masuda, N. Sugiura, and T. Doi
    • Journal Title

      Geophysical Research Letters

      Volume: 42 Issue: 12 Pages: 1-9

    • DOI

      10.1002/2015gl064538

    • Related Report
      2015 Annual Research Report
    • Peer Reviewed / Acknowledgement Compliant
  • [Journal Article] Role of the oceanic bridge in linking the 18.6 year modulation of tidal mixing and long-term SST change in the North Pacific2014

    • Author(s)
      Osafune, S.; Masuda, S.; Sugiura, N.
    • Journal Title

      Geophysical Research Letters

      Volume: 41 Issue: 20 Pages: 7284-7290

    • DOI

      10.1002/2014gl061737

    • Related Report
      2014 Research-status Report
    • Peer Reviewed / Acknowledgement Compliant
  • [Presentation] Subsurface structure of the Pacific Decadal Oscillation and its relation to the mode waters2016

    • Author(s)
      Satoshi Osafune, Shuhei Masuda, Nozomi Sugiura, and Toshimasa Doi
    • Organizer
      Ocean Science Meeting 2016
    • Place of Presentation
      Ernest N. Morial Convention Center (New Orleans, USA)
    • Year and Date
      2016-02-23
    • Related Report
      2015 Annual Research Report
    • Int'l Joint Research
  • [Presentation] 四次元変分法海洋環境再現データESTOCを用いた海洋表中層研究2014

    • Author(s)
      長船哲史、増田周平、杉浦望実
    • Organizer
      東京大学大気海洋研究所国際沿岸海洋研究センター研究集会 「北太平洋を中心とする循環と水塊過程」
    • Place of Presentation
      城山・中央公民館、岩手県上閉伊郡大槌町
    • Year and Date
      2014-08-26
    • Related Report
      2014 Research-status Report
    • Invited
  • [Presentation] 四次元変分法海洋環境再現データセットESTOCを用いた海洋表中層研究2014

    • Author(s)
      長船哲史、増田周平、杉浦望実
    • Organizer
      第18回データ同化夏の学校
    • Place of Presentation
      JAMSTECむつ研究所、青森県むつ市
    • Year and Date
      2014-08-21
    • Related Report
      2014 Research-status Report
  • [Presentation] Assessing impact of the 18.6-year period nodal tidal cycle on PDO using a 4D-VAR data assimilation system

    • Author(s)
      Osafune, S. ; Masuda, S. ; Sugiura, N.
    • Organizer
      the IAHS - IAPSO - IASPEI Joint Assembly
    • Place of Presentation
      Swedish Exhibition & Congress Centre, Gothenburg, Sweden
    • Related Report
      2013 Research-status Report
  • [Presentation] 四次元変分法海洋データ同化システムを用いた潮汐18.6年振動による北太平洋海面水温変動への影響評価2

    • Author(s)
      長船哲史, 増田周平, 杉浦望実
    • Organizer
      日本海洋学会秋季大会
    • Place of Presentation
      北海道大学、北海道札幌市
    • Related Report
      2013 Research-status Report
  • [Remarks] 長期海洋環境再現データセットESTOCの再現性評価

    • URL

      http://ebcrpa.jamstec.go.jp/rcgc/j/rr/201506estoc.html

    • Related Report
      2015 Annual Research Report

URL: 

Published: 2014-07-25   Modified: 2019-07-29  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi