[M-IS10] Paleoclimatology and paleoceanography

[MIS10-15] The study of reconstructing methods of temperature variation using tree-ring oxygen isotope

*Akane Tsushima¹, Masaki Sano², Zhen LI¹, Takeshi Nakatsuka¹, Koh Yasue³, Koji Fujita⁴ (1.Research Institute for Humanity and Nature, 2.Waseda University, 3. Shinshu Univ., 4.Graduate School of Environmental Studies, Nagoya University)

Keywords:Tree ring oxygen isotope, Temperature variation, Japan

The tree-ring δ¹⁸O is known to be an important proxy for reconstructing hydro-climate changes in monsoon Asia because the tree-ring δ¹⁸O is not controlled by ecological factors and is decided by 2 factors, one is δ¹⁸O in soil water and another is relative humidity. The δ¹⁸O in soil water reflect that in precipitation, but the precipitation δ¹⁸O is affected by some climate factors i.e., temperature, precipitation amount and atmospheric circulation pattern. Consequently, tree-ring δ¹⁸O changes influenced by not only soil water δ¹⁸O and relative humidity but also other climate factors. Therefore, we think that we can reconstruct not only precipitation variation but also temperature variation from tree-ring d¹⁸O. In this study, we discussed reconstruction method of temperature variation from tree-ring δ¹⁸O.