[S-GL17] Geochronology and Isotope Geology

[SGL17-P02] Proxy evaluation of tree-ring oxygen isotopic ratios in Myanmar for paleoclimate reconstruction

*Yumiko Watanabe¹, Zhen Li², Takeshi Nakatsuka² (1.Department of Earth and Planetary Scineces, Kyoto University, 2.Graduate School of Enviromental Studies, nviromental Studies, Nagoya University)

Keywords:tree ring, isotope, proxy

In Myanmar, monsoon precipitation has a significant impact on human life (e.g., water security and agricultural production), and thus it is critical to understand and predict precipitation variability. Meteorological observation has a short history in Myanmar and the observation data is limited. Accordingly, it is needed a reliable proxy to understand past rainfall variability in Myanmar.

Tree rings are useful to reconstruct terrestrial paleoclimate because of their precise dating and high time resolution. In this study, we measured tree-ring width and cellulose oxygen isotopic ratio of teak samples collected from Myanmar and compared them with meteorological data to comprehensively evaluate their reliability as paleoclimate proxies. The results suggest that the tree-ring width of teak could be valuable as a precipitation indicator during the rainy season, and the oxygen isotopic ratio may have information on the origin of precipitation.