[U-11] Climate change during the Quaternary and Anthropocene

[U11-P09] Last glacial Aisan monsoon history recorded as 10Be in sediments obtained from Lake Biwa, Japan

*Yusuke Yokoyama^1,2,3,4, Satomi Takahashi¹, Takahiro AZE¹, Masako Yamane¹, Yosuke Miyairi¹, Hiroyuki Kitagawa⁵, Hiroyuki Matsuzaki⁶, Keiji Takemura⁷ (1.Atmosphere and Ocean Research Institute, University of Tokyo, 2.Department of Earth and Planetary Science, Graduate School of Science, University of Tokyo, 3.Graduate Program on Environmental Science, University of Tokyo, 4.Research School of Physics, The Australian National University, 5.Institute for Space-Earth Environmental Research, Nagoya University, 6.MALT, The University Museum, University of Tokyo, 7.The Institute for Geothermal Sciences, Graduate School of Science, Kyoto University)

Keywords:

Lake Biwa,Asian Monsoon,Cosmogenic Nuclides,Earth Surface Processes

The measurement of sedimentary 10Be from Lake Biwa is used to understand monsoon activity from the last glacial period to the Holocene. An increase of approximately 3 to 5 times the 10Be flux is found in the lake sediments prior to the last glacial maximum (LGM) was found compared to the value at the top of the core (ca. 3 × 10^9 atoms/cm2/kyr), . This value drops to approximately 1.5 times the present value, with significant peaks occurring during Heinrich events (HEs). Comparisons with Chinese speleothem records, an East Asian Summer Monsoon (EASM) proxy, suggest that variations in the 10Be flux in the Lake Biwa region of Japan are controlled by changes in precipitation. These results indicate that Japan experienced a relatively wetter climate during the last glacial period, particularly during MIS3.