Study of mechanism for sea level variability along the Japanese coast on the timescales from 10 days to a decade using data assimilation

• Project/Area Number: 26400472
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: Japan, Meteorological Research Institute
• Principal Investigator: Usui Norihisa 気象庁気象研究所, 海洋・地球化学研究部, 主任研究官 (50370333)
• Co-Investigator(Renkei-kenkyūsha): HIROSE Nariaki 気象庁気象研究所, 海洋地球化学研究部, 研究官 (20748074)
• Research Collaborator: YASUDA Tamaki 気象庁, 地球環境海洋部・情報課, エルニーニョ情報管理官 ; FUKUDA Yoshikazu 気象庁, 地球環境海洋部, 海洋気象課調査官 ; MOTOYAMA Tatsuya 気象庁, 地球環境海洋部, 海洋気象情報室技術専門官
• Project Period (FY): 2014-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000); Fiscal Year 2016: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2015: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2014: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: 沿岸水位 / 沿岸捕捉波 / 異常潮位 / 黒潮続流 / 十年規模変動 / 貯熱量 / 対馬暖流 / データ同化 / 対馬海峡 / 海峡通過流量 / 中緯度偏西風 / 海洋再解析 / 黒潮 / 海洋モデル

Outline of Final Research Achievements

Four-dimensional variational ocean reanalysis for the western North Pacific (FORA-WNP30) was produced to study sea level variability along the Japanese coast on the timescales from 10 days to a decade. It is the first-ever dataset covering the western North Pacific over 3 decades at eddy-resolving resolution. FORA-WNP30 clarified a generation mechanism of an unusual tide that occurred in 2001. It was caused by a coastal-trapped waves (CTWs) induced as a result of a short-term fluctuation of the Kuroshio path. The CTWs play an important role not only in the unusual tide on 2011 but also in the long-term variability of the Japanese coastal sea level, which synchronizes with the decadal variability of the Kuroshio extension. It is also shown that the long-term coastal sea-level variability has a significant impact on long-term variability of ocean heat content in the Japan Sea by changing volume transport at the Tsushima Strait.

Research Products

• [Journal Article] Four-dimensional variational ocean reanalysis: a 30-year high-resolution dataset in the western North Pacific (FORA-WNP30) (2017)
  • Author(s): Usui, N., T. Wakamatsu,Y. Tanaka, N. Hirose, T. Toyoda, S. Nishikawa, Y. Fujii, Y. Takatsuki, H. Igarashi, H. Nishikawa, Y. Ishikawa, T. Kuragano, M. Kamachi
  • Journal Title: Journal of Oceanography Volume: 73 Issue: 2 Pages: 205-233
  • DOI: 10.1007/s10872-016-0398-5
  • NAID: 40021131632
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Development of a Four-Dimensional Variational Assimilation System for Coastal Data Assimilation around Japan (2015)
  • Author(s): Usui, N., Y. Fujii, K. Sakamoto, M. Kamachi
  • Journal Title: Monthly Weather Review Volume: 143 Issue: 10 Pages: 3874-3892
  • DOI: 10.1175/mwr-d-14-00326.1
  • Peer Reviewed / Acknowledgement Compliant
• [Presentation] Development of a four-dimensional variational assimilation system with a high-resolution coastal ocean model (2017)
  • Author(s): Usui, N., N. Hirose, Y. Fujii, K. Sakamoto, and S. Urakawa
  • Organizer: RIKEN International Symposium on Data Assimilation 2017
  • Place of Presentation: RIKEN AICS
  • Year and Date: 2017-02-27
  • Int'l Joint Research / Invited
• [Presentation] Intercomparison of sea level variation across the Tsushima Strait among tide gauge data, a coastal altimetry product and an ocean reanalysis FORA-WNP30 (2017)
  • Author(s): Hirose, N., N. Usui, T. Wakamatsu, Y. Tanaka, T. Toyoda, Y. Fujii, Y. Takatsuki, T. Kuragano, and M. Kamachi
  • Organizer: RIKEN International Symposium on Data Assimilation 2017
  • Place of Presentation: RIKEN AICS
  • Year and Date: 2017-02-27
  • Int'l Joint Research
• [Presentation] Intercomparison of sea level variation across the Tsushima Strait among tide gauge data, a coastal altimetry product and an ocean reanalysis FORA-WNP30 (2017)
  • Author(s): Hirose, N., N. Usui, T. Wakamatsu, Y. Tanaka, T. Toyoda, Y. Fujii, Y. Takatsuki, T. Kuragano, and M. Kamachi
  • Organizer: 10th Coastal Altimetry Workshop
  • Place of Presentation: San't Apollonia Augitorium
  • Year and Date: 2017-02-22
  • Int'l Joint Research
• [Presentation] 海洋モデル・同化を用いた黒潮研究－川辺先生の描いた黒潮像にどこまで近づけたか?－ (2017)
  • Author(s): 碓氷典久
  • Organizer: この10年の海洋物理学を振り返る（杉ノ原伸夫・川辺正樹記念シンポジウム）
  • Place of Presentation: 東京大学大気海洋研究所
  • Year and Date: 2017-01-28
  • Invited
• [Presentation] Four-dimensional variational Ocean ReAnalysis for the Western North Pacific over 30 years (FORA-WNP30) (2016)
  • Author(s): Hirose, N., Y. Takatsuki, N. Usui, T. Wakamatsu, Y. Tanaka, T. Toyoda, S. Nishikawa, Y. Fujii, H. Igarashi, H. Nishikawa, Y. Ishikawa, T. Kuragano, and M. Kamachi
  • Organizer: 2016 AGU Fall Meeting
  • Place of Presentation: Moscone center
  • Year and Date: 2016-12-15
  • Int'l Joint Research
• [Presentation] 日本海表層貯熱量の十年規模変動 (2016)
  • Author(s): 碓氷典久, 広瀬成章, 豊田隆寛, 藤井陽介, 高槻靖, 倉賀野連
  • Organizer: 日本海及び日本周辺海域の海況モニタリングと波浪計測に関する研究集会
  • Place of Presentation: 九州大学応用力学研究所
  • Year and Date: 2016-12-15
• [Presentation] 海洋長期再解析における日本海の流量‐貯熱量の長期変動について (2016)
  • Author(s): 広瀬成章, 碓氷典久, 豊田隆寛, 藤井陽介, 高槻靖, 倉賀野連
  • Organizer: 日本海洋学会2016年度秋季大会
  • Place of Presentation: 鹿児島大学郡元キャンパス
  • Year and Date: 2016-09-12
• [Presentation] 1970年代の渦解像再解析は可能か?：1971年異常潮位再現実験から (2016)
  • Author(s): 碓氷典久, 高槻靖, 若松剛, 田中裕介, 広瀬成章, 豊田隆寛, 藤井陽介, 倉賀野連
  • Organizer: 日本海洋学会2016年度秋季大会
  • Place of Presentation: 鹿児島大学郡元キャンパス
  • Year and Date: 2016-09-12
• [Presentation] データ同化の基礎 (2016)
  • Author(s): 広瀬成章
  • Organizer: 第20回データ同化夏の学校
  • Place of Presentation: 海洋研究開発機構むつ研究所
  • Year and Date: 2016-08-22
• [Presentation] Assimilation experiment for the largest-ever abnormal sea-level at the south coast of Japan in September 1971 (2016)
  • Author(s): Usui, N., N. Hirose, T. Toyoda, Y. Fujii, K. Sakamoto, Y. Takatsuki, G. Yamanaka, and T. Kuragano
  • Organizer: Asia Oceania Geosciences Society 13th Annual Meeting (AOGS2016)
  • Place of Presentation: China National Convention Centre
  • Year and Date: 2016-08-04
  • Int'l Joint Research
• [Presentation] 日本海の貯熱量と海峡通過流量の関係について (2016)
  • Author(s): 広瀬成章, 碓氷典久, 豊田隆寛, 藤井陽介, 高槻靖, 倉賀野連
  • Organizer: 研究集会「宗谷暖流を始めとした対馬暖流系の変動メカニズム」
  • Place of Presentation: 北海道大学低温科学研究所
  • Year and Date: 2016-07-01
• [Presentation] Relationship between upper ocean heat content in the Japan Sea and volume transport through the Tsushima Strait (2016)
  • Author(s): Hirose, N., N. Usui, Y. Tanaka, Y. Ishikawa, T. Toyoda, Y. Fujii, S. Nishikawa, H. Igarashi, H. Nishikawa, Y. Takatsuki, T. Kuragano, and M. Kamachi
  • Organizer: JpGU meeting 2016
  • Place of Presentation: 幕張メッセ
  • Year and Date: 2016-05-24
  • Int'l Joint Research
• [Presentation] Mechanism of interannual to decadal sea level variability along the Japanese coast (2016)
  • Author(s): Usui, N., K. Ogawa, T. Yasuda, N. Hirose, and T. Kuragano
  • Organizer: Ocean Sciences Meeting 2016
  • Place of Presentation: Ernest N. Morial Convention Center、米国ニューオリンズ
  • Year and Date: 2016-02-26
  • Int'l Joint Research
• [Presentation] 気象研における高解像度海洋データ同化システム開発の現状と今後に向けて (2016)
  • Author(s): 碓氷典久, 藤井陽介, 広瀬成章, 坂本圭, 高槻靖
  • Organizer: 第6回データ同化ワークショップ
  • Place of Presentation: 海洋研究開発機構横浜研究所、神奈川県横浜市
  • Year and Date: 2016-02-01
• [Presentation] FORAから見えてきた海の30年の歴史 (2016)
  • Author(s): 碓氷典久
  • Organizer: 最先端計算科学が描き出す海の30年 長期再解析FORAシンポジウム
  • Place of Presentation: 一橋大学 一橋講堂、東京都千代田区
  • Year and Date: 2016-01-20
• [Presentation] 北西太平洋海洋長期再解析（FORA-WNP30）IV：黒潮・黒潮続流の再現性 (2015)
  • Author(s): 碓氷典久, 若松剛, 田中裕介, 広瀬成章, 豊田隆寛, 藤井陽介, 西川史朗, 五十嵐弘道, 西川悠, 石川洋一, 高槻靖, 倉賀野連, 蒲地政文
  • Organizer: 日本海洋学会秋季大会
  • Place of Presentation: 愛媛大学城北キャンパス、愛媛県松山市
  • Year and Date: 2015-09-27
• [Presentation] Development of a four-dimensional variational assimilation system in the western North Pacific (2015)
  • Author(s): Usui, N., Y. Fujii, T. Kuragano, M. Kamachi
  • Organizer: 1st GODAE OceanView Data Assimilation Task Team (DA-TT) Workshop
  • Place of Presentation: Met Office、英国エクセター
  • Year and Date: 2015-05-20
  • Int'l Joint Research
• [Presentation] Mechanism for an unusual tide around the Seto Inland Sea in 2011 revealed by a coastal-assimilative model (2015)
  • Author(s): Usui, N., K. Ogawa, K. Sakamoto, Y. Fujii, T. Kuragano
  • Organizer: 18th Pacific-Asia Marginal Seas Meeting
  • Place of Presentation: 那覇市ぶんかテンブス館、沖縄県那覇市
  • Year and Date: 2015-04-21
  • Int'l Joint Research
• [Presentation] Development of a coastal monitoring and forecasting system at MRI/JMA (2015)
  • Author(s): Usui, N.
  • Organizer: OOPC2015 workshop “Future Prospects of Coastal Ocean Observations and Modeling in Japan”
  • Place of Presentation: 東北大学青葉山キャンパス、宮城県仙台市
  • Year and Date: 2015-04-17
  • Int'l Joint Research
• [Presentation] Sea level variability along the Japanese coast in response to changes in the Kuroshio-Kuroshio Extension system (2014)
  • Author(s): Norihisa Usui, Koji Ogawa, Tamaki Yasuda, Tsurane Kuragano
  • Organizer: 2014 AGU Fall meeting
  • Place of Presentation: Moscone Center
  • Year and Date: 2014-12-17
• [Presentation] 日本沿岸水位と黒潮・黒潮続流変動との関係 (2014)
  • Author(s): 碓氷典久、小川浩司、安田珠幾、倉賀野連
  • Organizer: 2014年度日本海洋学会秋季大会
  • Place of Presentation: 長崎大学文教キャンパス
  • Year and Date: 2014-09-15
• [Presentation] Covariations in sea-level along the Japanese coast and the Kuroshio-Kuroshio Extension system (2014)
  • Author(s): Norihisa Usui, Koji Ogawa, Kei Sakamoto, Tsurane Kuragano, Masafumi Kamachi
  • Organizer: AOGS 11th Annual Meeting
  • Place of Presentation: ロイトン札幌
  • Year and Date: 2014-07-31