Assessment of freshening of Antarctic Bottom Waters andchanges in fresh water cycle by stable oxygen isotope analysis

• Project/Area Number: 17510001
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Environmental dynamic analysis
• Research Institution: Hokkaido University
• Principal Investigator: AOKI Shigeru Hokkaido University, 低温科学研究所, 准教授 (80281583)
• Co-Investigator(Kenkyū-buntansha): TOYOTA Takenobu 北海道大学, 低温科学研究所, 助教 (80312411)
• Project Period (FY): 2005 – 2008
• Project Status: Completed (Fiscal Year 2008)
• Budget Amount: ¥4,110,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥510,000); Fiscal Year 2008: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2007: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2006: ¥600,000 (Direct Cost: ¥600,000); Fiscal Year 2005: ¥1,300,000 (Direct Cost: ¥1,300,000)
• Keywords: 南極底層水 / 陸棚水 / 酸素同位体比 / 海洋淡水化

Research Abstract

南極海沿岸の四割に及ぶ領域で南極底層水・沿岸陸棚水の特性変化の実態を把握し、あわせて酸素同位体比解析のための資料の収集とそれによる変動原因の考察を行った。南極底層水は全般的に低塩化しつつある。ロス海では特に顕著で、陸棚水の低塩化と関連している可能性があるが、酸素同位体比解析により氷床融解の影響が示唆された。酸素同位体比は底層水の生成源の推定にも有効であった。インド洋区における起源淡水として降雪と陸氷の分析を実施したところ、平均的には両者は十分区別可能で、本手法の有効性が示された。

Research Products

• [Journal Article] State of the Antarctic and Southern Ocean ClimateSystem (2009)
  • Author(s): Mayewski, P.A., M.P. Meredith, C.P.Summerhayes, J. Turner, A. Worby, P.J. Barrett, G. Casassa, N.A.N.Bertler, T. Bracegirdle, A. C.Naveira-Garabato, D. Bromwich, H.Campbell, G.H. Hamilton, W.B. Lyons, K.A. Maasch, S. Aoki, C. Xiao, and T.van Ommen
  • Journal Title: Rev. Geophys 47, RG1003,doi : 10.1029/2007RG000231
  • Peer Reviewed
• [Journal Article] The Antarctic Oscillation andSouthern Ocean sea surface heightbasin mode (2009)
  • Author(s): Iijima, Y., S. Aoki, and T. Kutsuwada
  • Journal Title: J. Oceanogr 65(1) Pages: 53-60
  • Peer Reviewed
• [Journal Article] Deep western boundary current andsouthern frontal systems of theAntarctic Circumpolar Currentsoutheast of the Kerguelen Plateau (2008)
  • Author(s): Aoki, S., N. Fujii, S. Ushio, Y.Yoshikawa, S. Watanabe, G. Mizuta, Y.Fukamachi., and M. Wakatsuchi
  • Journal Title: J. Geophys Res., 113, C08038, doi : 10.1029/2007JC004627
  • Peer Reviewed
• [Journal Article] 南極陸棚斜面横断東経115度ラインにおける酸素安定同位体比分布, (2008)
  • Author(s): 青木茂
  • Journal Title: 九州大学応用力学研究所所報 135 Pages: 89-93
  • NAID: 120001219856
• [Journal Article] 干渉SAR処理を用いた南極接地線(grounding line)の精密決定 (2008)
  • Author(s): 山之口勤・土井浩一郎・澁谷和雄・青木茂
  • Journal Title: 九州大学応用力学研究所所報 135 Pages: 95-99
  • NAID: 120001219857
• [Journal Article] Sea Ice Thickness andSnow Depth Data Collected by the Ship-based Video Observations during 29th to 48th Japanese Antarctic Research Expedition, JARE DATA REPORT (2008)
  • Author(s): Uto, S., H. Shimoda, S. Aoki, S. Ushio, F.Nishio, H. Wakabayashi, G. Hashida,K. Goto-Azuma, A. Furusaki, and K. Tateyama
  • Journal Title: Jpn. Antarct. Res. Exped., Tokyo 307 Pages: 16-16
• [Journal Article] Deep western boundary current and southern frontal systems of the Antarctic Circumpolar Current southeast of the Kerguelen Plateau (2008)
  • Author(s): Aoki, et.al.
  • Journal Title: Journal of Geophysical Research 113(C08038)
  • Peer Reviewed
• [Journal Article] 南極陸棚斜面横断東経115度ラインにおける酸素安定同位体比分布 (2008)
  • Author(s): 青木茂
  • Journal Title: 九州大学応用力学研究所所報 135 Pages: 89-93
  • NAID: 120001219856
• [Journal Article] Formation regions of Subantarctic Mode Water detected by OFES and Argoprofiling floats (2007)
  • Author(s): Aoki, S., M. Hariyama, H. Mitsudera, H. Sasaki, and Y. Sasai
  • Journal Title: Geophys. Res. Lett L10606, doi : 10.1029/2007GL029828 Pages: 34-34
  • Peer Reviewed
• [Journal Article] Aseries of cyclonic eddies in the Antarctic Divergence off Adelie Coast (2007)
  • Author(s): Aoki, S., D. Fukai, T. Hirawake, S. Ushio, S.R. Rintoul, H. Hasumoto, T.Ishimaru, H. Sasaki, T. Kagimoto, Y. Sasai, and H. Mitsudera
  • Journal Title: J. Geophys. Res. C05019, doi : 10.1029/2006JC003712 Pages: 112-112
  • Peer Reviewed
• [Journal Article] Observationsof small-scale disturbances of the SubantarcticFront in the Indian Ocean sector (2007)
  • Author(s): Aoki, S., and K. Akitomo
  • Journal Title: Deep-SeaResearchPartI 54, doi10.1016/j.dsr.2006.12.002 Pages: 320-339
  • Peer Reviewed
• [Journal Article] A series of cyclonic eddies in the Antarctic Divergence off Adelie Coast (2007)
  • Author(s): Aoki, S., et. al.
  • Journal Title: Journal of Geophysical Research 112
  • Peer Reviewed
• [Journal Article] Formation regions of Subantarctic Mode Water detected by OFES and Argo profiling floats (2007)
  • Author(s): Aoki, S., et. al.
  • Journal Title: Geophysical Research Letters 34
  • Peer Reviewed
• [Journal Article] Observations of small-scale disturbances of the Subantarctic Front in the Indian Ocean sector (2007)
  • Author(s): Aoki, S., et al.
  • Journal Title: Deep-Sea Research Part I 54 Pages: 320-339
• [Journal Article] Frontalpositions and mixed layer evolution inSeasonal Ice Zone along 140 deg E linein 2001/02 (2006)
  • Author(s): Aoki, S., S.R. Rintoul, H. Hasumoto, and H. Kinoshita
  • Journal Title: Polar Bioscience 20 Pages: 1-20
  • Peer Reviewed
• [Journal Article] Frontal positions and mixed layer evolution in Seasonal Ice Zone along 140 deg E line in 2001/02 (2006)
  • Author(s): Aoki, S., et al.
  • Journal Title: Polar Bioscience 20 Pages: 1-20
• [Journal Article] Inter-annual variability ofchlorophyll and sea-ice in the Antarctic Divergence region : an attempt to derive theirquantitative relationship. (2005)
  • Author(s): Hirawake, T., S. Kudoh, S. Aoki, T. Odate, and M. Fukuchi
  • Journal Title: International Journal of Remote Sensing Vol.26(10) Pages: 2035-2044
  • Peer Reviewed
• [Journal Article] Freshening of the Adelie Land Bottom Water near 140°E (2005)
  • Author(s): Aoki, S., S.R. Rintoul, S. Ushio, S. Watanabe, and N.L. Bindoff
  • Journal Title: Geophys. Res. Lett. Vol.32, L23601, doi10.1029/2005GL024246
  • Peer Reviewed
• [Journal Article] Interdecadal watermass changes in the Southern Ocean between 30E and 160E (2005)
  • Author(s): Aoki,S., N. L. Bindoff, and J. A. Church
  • Journal Title: Geophys. Res. Lett Vol. 32, L07607, doi10.1029/2004GL022220
  • Peer Reviewed
• [Journal Article] Freshening of the Adelie Land Bottom Water near 140°E (2005)
  • Author(s): Aoki, S. et al.
  • Journal Title: Geophysical Research Letters 32
• [Presentation] Sea ice production in the polynya andthe associated bottom water formationoff the Cape Darnley (2009)
  • Author(s): Ohshima, K.I., T. Tamura, Y. Fukamachi, S. Aoki
  • Organizer: East Antarctica, 9th International Conference on Southern Hemisphere Meteorology and Oceanography
  • Place of Presentation: Melborone Convention Center, Melborone
  • Year and Date: 2009-02-11
• [Presentation] Mooring measurement of the deep westernboundary current over the easternflank of the Kerguelen Plateau in theIndian sector of the Antarctic (2009)
  • Author(s): Fukamachi, Y., S. Aoki, J. Church, S. Rintoul, M. Rosenberg, and M. Wakatsuchi
  • Organizer: 9thInternational Conference on Southern Hemisphere Meteorology and Oceanography
  • Place of Presentation: Melborone Convention Center, Melborone
  • Year and Date: 2009-02-02
• [Presentation] 晩冬季のウェッデル海北西部海氷上の積雪の特性について (2008)
  • Author(s): 豊田威信, Christian Haas, Marcel Nicolaus, Zhijun Li, 青木茂
  • Organizer: 極域気水圏・生物合同シンポジウム
  • Place of Presentation: 東京, 国立極地研究所
  • Year and Date: 2008-11-20
• [Presentation] Development of gounding line database at Antarctica by In SAR technique (2008)
  • Author(s): Yamanokuchi, T., K. Doi, K. Shibuya, and S.Aoki
  • Organizer: Proceedings of International Geoscience and remote sensingsymposium(IGARSS08)
  • Place of Presentation: John B. Hynes Veterans Memorial Convention Center, Boston, Massachusetts
  • Year and Date: 2008-07-10
• [Presentation] Recentproperty changes of Antarctic Bottom Waters (2008)
  • Author(s): Aoki, S., M. Naganobu, and N. L. Bindoff
  • Organizer: SCAR/IASC Open Science conference
  • Place of Presentation: St. Petersberg, Arctic and Antarctic ResearchInstitute
  • Year and Date: 2008-07-09
• [Presentation] Downslope mixing of Antarctic Bottom Water from East Antarctic polynyas (2008)
  • Author(s): Williams, G. D., S. Aoki, S. J.Marsland, N.L. Bindoff, Y. Fukamachi, S.R. Rintoul, and B. Galton-Fenzi
  • Organizer: SCAR/IASC Open Science conference
  • Place of Presentation: St. Petersberg, Arctic and Antarctic Research Institute
  • Year and Date: 2008-07-09
• [Presentation] Recent property changes of Antarctic Bottom Waters (2008)
  • Author(s): Aoki, Naganobu, and Bindoff
  • Organizer: SCAR/IASC Open Science conference
  • Place of Presentation: ロシア・サンクトペテルブルグ・北極南極研究所
  • Year and Date: 2008-07-09
• [Presentation] ケルゲレン海台南東部における深層西岸境界流と南極周極流南部フロントの構造について (2007)
  • Author(s): 青木茂, 藤井信宏, 牛尾収輝, 吉川泰, 渡邉修一, 水田元太, 深町康, 若土正曉
  • Organizer: 第30回極域気水圏シンポジウム
  • Place of Presentation: 東京, 国立極地研究所
  • Year and Date: 2007-11-21
• [Presentation] 冬季リュツォ・ホルム湾定着氷下の全溶存無機炭素濃度の鉛直分布 (2007)
  • Author(s): 橋田元, 青木茂, 中岡慎一郎, 吉川久幸
  • Organizer: 第30回極域気水圏シンポジウム
  • Place of Presentation: 東京, 国立極地研究所
  • Year and Date: 2007-11-21
• [Presentation] ケルゲレン海台南東部における深層西岸境界流と南極周極流南部フロントの構造について (2007)
  • Author(s): 青木茂, 藤井信宏, 牛尾収輝, 吉川泰, 渡邉修一, 水田元太, 深町康, 若土正曉
  • Organizer: 日本海洋学会秋季大会
  • Place of Presentation: 那覇市, 琉球大学
  • Year and Date: 2007-09-26
• [Presentation] ケルゲレン海台南東部における深層西岸境界流と南極周極流南部フロントの構造について (2007)
  • Author(s): 青木 茂, 他7名
  • Organizer: 2007年度日本海洋学会秋季大会
  • Place of Presentation: 沖縄・琉球大学
  • Year and Date: 2007-09-26
• [Presentation] Recent freshening of the Antarctic Bottom Water in the Australian-Antarctic basin (2007)
  • Author(s): Aoki, S.
  • Organizer: ヨーロッパ地球物理学連合
  • Place of Presentation: ウィーン・オーストリアセンター
  • Year and Date: 2007-04-17
• [Presentation] Recent fresheningof the Antarctic Bottom Water in theAustralian-Antarctic basin Recent fresheningof the Antarctic Bottom Water in theAustralian-Antarctic basin (2007)
  • Author(s): Aoki, S.(Invited)
  • Organizer: EGUGeneral Assembly 2007
  • Place of Presentation: Austria Center Vienna, Vienna.
  • Year and Date: 2007-04-16
• [Presentation] Large scale circulationfrom 30-80deg E along the Antarcticcoastline (2007)
  • Author(s): Klocker, A., Meijers, A., Bindoff, N., Williams, G., Marsland, M., Aoki, S., Iijima, Y
  • Organizer: EGU General Assembly 2007
  • Place of Presentation: Austria Center Vienna, Vienna
  • Year and Date: 2007-04-16
• [Presentation] 東経140度付近におけるアデリーランド底層水の低塩化傾向 (2006)
  • Author(s): 青木茂, Steve Rintoul, 牛尾収輝, 渡辺修一, Nathan Bindoff
  • Organizer: 極域気水圏・生物合同シンポジウム
  • Place of Presentation: 東京, 国立極地研究所
  • Year and Date: 2006-11-20
• [Presentation] 南大洋亜南極フロントにおける小規模擾乱の観測 (2006)
  • Author(s): 青木茂, 秋友和典
  • Organizer: 日本海洋学会秋季大会
  • Place of Presentation: 名古屋, 名古屋大学
  • Year and Date: 2006-09-26
• [Presentation] Interdecadal water-mass changesin the Indian sector of the Southern Ocean and their impacts on sea levelrise (2005)
  • Author(s): Aoki, S., N.L. Bindoff, and J.A. Church(Invited)
  • Organizer: IAMAS 2005
  • Place of Presentation: Beijing International Convention Center, Beijing, China
  • Year and Date: 2005-08-05
• [Remarks] 2008. 5. 31. 親子講座「南極のふしぎ体験」(主催 : 札幌商工会議所)
  • URL: http://www.b-info.jp/scci-soumu/index.cfm?id=24203
• [Remarks] 2009. 3. 8. 第3回気象サイエンスカフェ南極の今~氷が語る環境の変化~紀伊国屋書店(主催 : 札幌管区気象台)
  • URL: http://www.sapporo-jma.go.jp/topix/cafe-h21/cafe-h21.html