Reconstruction of water masses in the Kuroshio region based on Radiolarian assemblages

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K17782
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Stratigraphy/Paleontology
• Research Institution: The University of Tokyo (2016-2018); National Institute of Advanced Industrial Science and Technology (2015)
• Principal Investigator: Matsuzaki Kenji M. 東京大学, 大気海洋研究所, 助教 (50728582)
• Research Collaborator: Itaki Takuya
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 北西太平洋 / 黒潮 / 古海洋学 / 水温

Outline of Final Research Achievements

Radiolarians are marine Protista bearing test of biogenic silica and inhabit the shallow and deep-water depth. In this research we have clarified radiolarian species patio-temporal distribution in area influenced by the Kuroshio Current participating to oceanographic survey in this area. Based on this study we could clarify species temperature dependent and these species were selected for define a method for estimate sea surface and intermediate water temperature of the past.
We also investigate changes in radiolarian assemblages in a IODP core collected during the expedition 346 in the east China Sea, which cover the last 400,000 years. Therefore based on radiolarians we documented changes in Kuroshio Current intensity of that area for the past 400,000 years based on the basic knowledges obtained from our modern research.

Free Research Field

微古生物学、古海洋学

Academic Significance and Societal Importance of the Research Achievements

球温暖化の影響で黒潮が蛇行する恐れもあります。その場合、国内の漁業と気候に影響し、現社会の生活習慣などに影響するので過去の気候を遡って違う黒潮の設定でどんな気候だったかを巡る事で地球温暖化防止に繋がる。
本研究では新しい指標の解明を現生放散虫から確立して、過去４０万年間の気候を保存する海洋コアの研究をして以上の問題に多少な答えを出す事を目標としていました。そこで、この課題の最終論文にも報告したように黒潮は海水温・気温だけではなく東シナ海では一時生産性にも大きい影響を与えている事考えらる事が分かりましたの今後の地球について少し新たな情報を公開できたと考えています。