Variations in the East Asian summer monsoon for the last 400 ky based on foraminiferal Mg/Ca and oxygen isotope in the northern East China Sea

• Project/Area Number: 15K21656
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Environmental dynamic analysis; Geology
• Research Institution: National Museum of Nature and Science, Tokyo
• Principal Investigator: Kubota Yoshimi 独立行政法人国立科学博物館, 地学研究部, 研究員 (80710946)
• Research Collaborator: HOLBOURN Ann ; CLEMENS Steven ; KIMOTO Katsunori ; SAGAWA Takuya
• Project Period (FY): 2015-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2017: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2016: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2015: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: アジアモンスーン / 氷期間氷期サイクル / 浮遊性有孔虫 / Mg/Ca / 酸素同位体比 / 塩分復元 / 東アジア夏季モンスーン / 有孔虫 / 軌道要素 / 東シナ海 / IODP / モンスーン / 微量元素分析 / Mg/Ca古水温

Outline of Final Research Achievements

We reconstructed oxygen isotope (δ18O )of seawater by using Mg/Ca and δ18O of planktic foraminifera for the last 400 k in the northern East China Sea in order to understand orbital scale East Asian summer monsoon variability. As a results, unlike Yangtze River Valley speleothem δ18O, dominated almost exclusively by precession-band (23-ky) cyclicity, local seawater δ18O is dominated by eccentricity (100-ky) and obliquity (41-ky) cycles, with almost no precession-scale variance.. These results, consistent with records outside the Yangtze River Valley, suggest that East Asian monsoon rainfall is more sensitive to greenhouse gas and high latitude ice sheet forcing than to direct insolation forcing.

Research Products

• [Int'l Joint Research] Brown University(米国)
• [Int'l Joint Research] Korea Maritime and Ocean Univeristy(韓国)
• [Int'l Joint Research] Christian-Albrechts-Universitat(ドイツ)
• [Int'l Joint Research] Key Laborat. of Mar. Geol. and Envir.(中国)
• [Int'l Joint Research] Universiteit Utrecht(オランダ)
• [Int'l Joint Research] ブラウン大学(米国)
• [Int'l Joint Research] クリスチャン アブレヒト大学(ドイツ)
• [Int'l Joint Research] 韓国海洋大学(韓国)
• [Int'l Joint Research] ユトレヒト大学(オランダ)
• [Int'l Joint Research] ブラウン大学(米国)
• [Int'l Joint Research] クリスチャン・アルブレヒト大学キール(ドイツ)
• [Journal Article] High-resolution and -precision correlation of dark and light layers in the Quaternary hemipelagic sediments of the Japan Sea recovered during IODP Expedition 346 (2018)
  • Author(s): R. Tada, T. Irino, K. Ikehara, A. Karasuda, S. Sugisaki, C. Xuan, T. Sagawa, T. Itaki, Y. Kubota, et al.
  • Journal Title: Progress in Earth and Planetary Science Volume: 5 Issue: 1 Pages: 19-19
  • DOI: 10.1186/s40645-018-0167-8
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Differing oxygen isotopic signals of two Globigerinoides ruber (white) morphotypes in the East China Sea: Implications for paleoenvironmental reconstructions. (2017)
  • Author(s): Carter, A., Clemens, S., Kubota, Y., Holbourn, A. & Martin, A.
  • Journal Title: Marine Micropaleontology Volume: - Pages: 1-9
  • DOI: 10.1016/j.marmicro.2017.01.001
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Proceedings of the Integrated Ocean Drilling Program (2015)
  • Author(s): Tada, R., R.W. Murray, C.A. Alvarez Zarikian, W.T. Anderson Jr., M.-A. Bassetti, B.J. Brace, S.C. Clemens,M.H. da Costa Gurgel, G.R. Dickens, A.G. Dunlea, S.J. Gallagher, L. Giosan, A.C.G. Henderson, A.E. Holbourn, K. Ikehara, T. Irino, T. Itaki, A. Karasuda, C.W. Kinsley, Y. Kubota, G.S. Lee, K.E. Lee, J. Lofi, et al.
  • Journal Title: Proceedings of the Integrated Ocean Drilling Program Volume: 346
  • DOI: 10.2204/iodp.proc.346.101.2015
  • Open Access / Int'l Joint Research
• [Presentation] Variations in East Asian summer monsoon in the last 400 ky deduced from results of Mg/Ca-sea surface temperature and oxygen isotope of IODP Site U1429 (2017)
  • Author(s): Kubota, Y., E. Wakisaka, S.C. Clemens, A. Holbourn, K-E. Lee, M. Ziegler, M., K. Horikawa, K. Kimoto
  • Organizer: JpGU-AGU Joint Meeting
  • Int'l Joint Research
• [Presentation] Intermitted Occurrence of Millennial-scale Variability of East Asian Summer Monsoon before 1.45 Ma based on the High-resolution Br Record of the Japan Sea Sediments, Paleoclimate variability in the Indo-Pacific region (2017)
  • Author(s): Tada, R., A. Seki, M. Ikeda, T. Irino, K. Ikehara, A. Karasuda, S. Sugisaki, T. Sagawa, T. Itaki, Y. Kubota, M. Murayama, S. Lu, R. W. Murray, C. A Alvarez Zarikian and IODP Exp. 346 Scientists
  • Organizer: American Geophysical Union fall meeting 2017
  • Int'l Joint Research
• [Presentation] 東シナ海北部サイトU1429の浮遊性有孔虫Mg/Caおよび酸素同位体比に基づく東シナ海の過去40万年の環境変動と東アジア夏季モンスーン (2017)
  • Author(s): 久保田好美・脇坂恵津子，Steven Clemens, Ann Holbourn, Kyung Eun Lee, Martin Ziegler, 木元克典，堀川恵司
  • Organizer: 日本古生物学会 第166 回例会
• [Presentation] Variations in the East Asian Summer Monsoon during the Last 400 kyr Reconstructed Using Oxygen Isotope and Mg/Ca-Derived Sea Surface Temperatures at IODP Site U1429 (2016)
  • Author(s): Kubota Y, Wakisaka E, Clemens S, Holbourn A, Lee KE, Ziegler M, Kimoto K, Horikawa K.
  • Organizer: Goldschmidt2016
  • Place of Presentation: パシフィコ横浜（神奈川県・横浜市）
  • Year and Date: 2016-07-30
  • Int'l Joint Research
• [Presentation] A 400 ky record of Mg/Ca-based sea surface temperature at East China Sea Site U1429 (2016)
  • Author(s): Kubota Y., E. Wakisaka, S. C. Clemens, A. Holbourn, K. Horikawa, K. Kimoto
  • Organizer: Asian Monsoon IODP Expedition 346 2nd (Science) Postcruise Meeting
  • Place of Presentation: Melbourne（Australia)
  • Year and Date: 2016-01-21
  • Int'l Joint Research
• [Presentation] East China Sea δ18O Record Detects Millennial-Scale Changes in the East Asian Summer Monsoon (2015)
  • Author(s): Gleeman, E., S. Clemens, A. Lawman,Y. Kubota, A. Holbourn, A. Martin
  • Organizer: AGU fall meeting
  • Place of Presentation: San Francisco（USA)
  • Year and Date: 2015-12-12
  • Int'l Joint Research
• [Presentation] 東シナ海の高解像度水温復元に基づく海洋酸素同位体ステージ5での水温変動復元 (2015)
  • Author(s): 脇坂恵都子，久保田好美，堀川恵司，Ann Holbourn，Steve Clemens
  • Organizer: 地球環境史学会年会
  • Place of Presentation: 東京大学（東京都文京区）
  • Year and Date: 2015-11-21
• [Presentation] Variations in East Asian summer monsoon deduced from 400,000 year records of Mg/Ca sea surface temperature and Ba/Ca of IODP Expedition 346 Sites U1428 and U1429 (2015)
  • Author(s): Kubota, Y., E. Wakisaka, K. Horikawa, A. Holbourn, S. C. Clemens, K. Kimoto, R. Tada, R. W. Murray, C. A. Alvarez Zarikian, IODP Expedition 346 Scientists
  • Organizer: INQUA2015
  • Place of Presentation: 名古屋国際会議場（愛知県名古屋市熱田区）
  • Year and Date: 2015-07-27
  • Int'l Joint Research
• [Presentation] 統合国際深海掘削計画（IODP）346次航海で採取された縁海海底堆積物の高精度年代決定 (2015)
  • Author(s): 佐川 拓也, 多田 隆治, 池原 研, 入野 智久, 板木 拓也, 杉崎 彩子, 久保田 好美, 烏田 明典, Chuang Xuan, 長橋 良隆, 里口 保文, 中川 毅, Murray Richard W., Alvarez-Zarikian Carlos A., Expedition 346 Scientists
  • Organizer: 日本地球惑星連合大会2015
  • Place of Presentation: 幕張メッセ（千葉県千葉市美浜区）
  • Year and Date: 2015-05-25