Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Oral

M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS10] Paleoclimatology and paleoceanography

Thu. May 24, 2018 3:30 PM - 5:00 PM A07 (Tokyo Bay Makuhari Hall)

convener:Yusuke Okazaki(Department of Earth and Planetary Sciences, Graduate School of Science, Kyushu University), Atsuhiko Isobe(Research Institute for Applied Mechanics, Kyushu University), Akihisa Kitamura(静岡大学理学部地球科学教室, 共同), Masaki Sano(Faculty of Human Sciences, Waseda University), Hitoshi Hasegawa(Faculty of Science and Technology, Kochi University), Akira Oka(Atmosphere and Ocean Research Institute, The University of Tokyo), Michinobu Kuwae(Center for Marine Environmental Studies), Chairperson:Kuwae Michinobu(愛媛大学沿岸環境科学研究センター)

4:00 PM - 4:15 PM

[MIS10-31] Multi-decadal climate variabilities during mid-Holocene inferred from a stalagmite in Okinawa

*Ryu Uemura1, Kanako Omine1, Kosuke Masaka1, Ryuji Asami2, Mahjoor Ahmad Lone3, Yu-Chen Chou3, Chuan-Chou Shen3 (1.University of the Ryukyus, 2.Tohoku University, 3.National Taiwan University)

Keywords:Holocene, stalagmite, stable isotope, fluid inclusion

Holocene Asian summer monsoon was influenced by solar activity in Middle East and mainland China. However, this relationship is still unclear in the maritime margin of East Asian monsoon territory. In this study, to evaluate the multi-decadal variability of temperature and regional monsoon intensity in the western Pacific region, we measured carbonate oxygen isotope ratios and H/O isotopic compositions of fluid-inclusion water from Holocene stalagmite, HSN1, collected in Minami daito island, Okinawa, Japan. Although oxygen isotope ratio of carbonate has been used as a proxy for monsoon intensity in Asian region, it is difficult to separate two influencing factors; rain-water isotope ratio and calcite formation temperature. Isotopic analysis of fluid inclusion allows us to separate these factors and provides quantitative estimate for temperature. A robust age model was established with precise U-Th ages from 6 to 7.5 thousand years ago. This sample allow us to evaluate multi-decadal variability during mid-Holocene because of the high-growth rate of 180 μm/yr. In the presentation, we will compare our stalagmite proxy records with other marine, terrestrial, and also high-latitude paleoclimate records to clarify different forcings and teleconnections.