Multiscale analysis of Asian Monsoon over the past 640 ka

作     者：Yalan ZENG Shitao CHEN Shaohua YANG Yijia LIANG Yongjin WANG 

作者机构：Key Laboratory of Virtual Geographic Environment Ministry of Education School of Geography ScienceNanjing Normal University State Key Laboratory of Cultivation Base of Geographical Environment Evolution (Jiangsu Province) Jiangsu Center for Collaborative Innovation in Geographical Environment Resource Development and Application 

出 版 物：《Science China Earth Sciences》 (中国科学（地球科学英文版）)

年 卷 期：2019年第62卷第5期

页      面：843-852页

核心收录：

学科分类：07[理学] 0708[理学-地球物理学] 0704[理学-天文学] 

基　　金：supported by National Natural Science Foundation of China(Grant No.41572340) Priority Academic Program Development of Jiangsu Higher Education Institutions(Grant No.164320H116) 

主　　题：Empirical mode decomposition (EMD) Asian Monsoon Oxygen isotope records Semiprecession 5 ka cycle 

摘      要：The empirical mode decomposition(EMD) method is used to re-analyse the high-resolution and precisely-dated stalagmite record from Chinese caves over the past 640 ka. Results show that(1) the variation in the Asian Monsoon can be completely decomposed into ten quasiperiod oscillations, among which the precession and semiprecession band oscillations are the most prominent periodicities, with contribution rates of 31.1% and 30.7%, respectively;(2) the cross-spectrum analysis of the semiprecession component and bi-hemisphere insolation(BHI) are strongly correlated, indicating an amplified response of precipitation and temperature variability to the interhemispheric insolation in the low-latitude regions, thus further affecting the intensity of the Asian Monsoon;(3) on millennial timescales, obvious oscillations at the 5 ka and 1–2 ka bands roughly correspond to the classical Bond and Dansgaard-Oeschger(DO) cycles. Additionally, a strong correlation is found between the detrended stalagmite δ18 O records and Ca/Sr sequence from the North Atlantic(especially at the 5 ka band). This result means that the 5 ka cycle is characteristic of the glacial-interglacial cycle since the middle and late Pleistocene and may imply that climate change on the millennial timescale is the result of an interaction between global ice volume and insolation.