title: Variability of stalagmite-inferred Indian monsoon precipitation over the past 252,000 y.
abstract: A speleothem δ(18)O record from Xiaobailong cave in southwest China characterizes changes in summer monsoon precipitation in Northeastern India, the Himalayan foothills, Bangladesh, and northern Indochina over the last 252 kyr. This record is dominated by 23-kyr precessional cycles punctuated by prominent millennial-scale oscillations that are synchronous with Heinrich events in the North Atlantic. It also shows clear glacial-interglacial variations that are consistent with marine and other terrestrial proxies but are different from the cave records in East China. Corroborated by isotope-enabled global circulation modeling, we hypothesize that this disparity reflects differing changes in atmospheric circulation and moisture trajectories associated with climate forcing as well as with associated topographic changes during glacial periods, in particular redistribution of air mass above the growing ice sheets and the exposure of the "land bridge" in the Maritime continents in the western equatorial Pacific.
authors.affiliation: State Key Lab of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710075, China; Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an 710049, China; yanjun_cai@ieecas.cn ifung@berkeley.edu.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Cai
authors.affiliation: Center for Atmospheric Sciences, University of California, Berkeley, CA 94720; yanjun_cai@ieecas.cn ifung@berkeley.edu.
authors.forename: Inez Y
authors.initials: IY
authors.lastname: Fung
authors.affiliation: Department of Earth Sciences, University of Minnesota, Minneapolis, MN 55455;
authors.forename: R Lawrence
authors.initials: RL
authors.lastname: Edwards
authors.affiliation: State Key Lab of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710075, China; Joint Center for Global Change Studies, Beijing 100875, China;
authors.forename: Zhisheng
authors.initials: Z
authors.lastname: An
authors.affiliation: Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an 710049, China; Department of Earth Sciences, University of Minnesota, Minneapolis, MN 55455;
authors.forename: Hai
authors.initials: H
authors.lastname: Cheng
authors.affiliation: Department of Geological Sciences, Brown University, Providence, RI 02912;
authors.forename: Jung-Eun
authors.initials: JE
authors.lastname: Lee
authors.affiliation: State Key Lab of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710075, China;
authors.forename: Liangcheng
authors.initials: L
authors.lastname: Tan
authors.affiliation: High-Precision Mass Spectrometry and Environment Change Laboratory, Department of Geosciences, National Taiwan University, Taipei 106, Taiwan; and.
authors.forename: Chuan-Chou
authors.initials: CC
authors.lastname: Shen
authors.affiliation: Earth Observatory of Singapore, Nanyang Technological University, Singapore 639798.
authors.forename: Xianfeng
authors.initials: X
authors.lastname: Wang
authors.affiliation: Center for Atmospheric Sciences, University of California, Berkeley, CA 94720;
authors.forename: Jesse A
authors.initials: JA
authors.lastname: Day
authors.affiliation: State Key Lab of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710075, China;
authors.forename: Weijian
authors.initials: W
authors.lastname: Zhou
authors.affiliation: Department of Earth Sciences, University of Minnesota, Minneapolis, MN 55455;
authors.forename: Megan J
authors.initials: MJ
authors.lastname: Kelly
authors.affiliation: Center for Atmospheric Sciences, University of California, Berkeley, CA 94720;
authors.forename: John C H
authors.initials: JC
authors.lastname: Chiang
keywords: Indian summer monsoon; glacial–interglacial; precipitation; stalagmite; δ18O