ORIGINAL ARTICLE Climate fluctuation on a kiloyear scale during the Late Last Glacial in Mu Us Desert, China: evidence from Rb and Sr contents and ratios Yuejun Si • Baosheng Li • David Dian Zhang • Xiaohao Wen • Fengnian Wang • Shuhuan Du • Dongfeng Niu • Yihua Guo Received: 8 May 2013 / Accepted: 14 May 2014 Ó Springer-Verlag Berlin Heidelberg 2014 Abstract The MGS2 segment of the Milanggouwan stratigraphical section in China’s Salawusu River Valley records 5.5 sedimentary cycles consisting of dune sands alternating with fluviolacustrine facies or/and palaeosols. The high Rb and Sr contents and low Rb/Sr ratios in the fluviolacustrine facies indicate the presence of a warm and humid climate, and vice versa for a dry and cold climate. Rb and Sr appeared to have 5.5 element cycles that are consistent with the sedimentation changes, and each cycle lasts about 2 ka on average. This study suggests that the observed cycles mainly resulted from variations in the strength of the East Asian winter and summer monsoons, and the MGS2 segment experienced six cold-dry winter monsoons and five warm-humid summer monsoons during the OIS2. In addition, the millennial-scale monsoonal cli- mate fluctuations revealed by the element cycles corre- sponded well with the Dansgaard–Oeschger cycles recorded in the Greenland ice cores and Heinrich events in the North Atlantic marine sediments. Therefore, the mon- soonal climate fluctuations revealed by the Rb and Sr in the MGS2 segment were likely triggered by global climate change. Keywords Mu Us Desert Á Milanggouwan section Á Rb and Sr Á Kiloyear-scale climate changes Á Late last glacial Introduction In the past two decades, analyses of polar ice cores (Dansgaard et al. 1993; Grootes et al. 1993; John et al. 1992), marine sediments (Bond and Lotti 1995; Bond et al. 1999), stalagmites (Genty et al. 2003) and many other geological records reveal that there exist kiloyear-scale climate fluctuations at high latitudes in the Northern Hemisphere during the Last Glacial. The climate instability at that time has also been recorded in a number of Chinese geological deposits (Wang et al. 2001; Yao 1999; Yan et al. 1996; An 2002; Lu et al. 2004). The Late Last Glacial, namely, the oxygen isotope stage 2 (OIS2) is the latest glacial period, and the climate then was quite different from today. At that time, solar radiation was minimal in the North Hemisphere (Berger 1988), high-latitude ice sheet was at maximum expanded (Peltier 1994; Yokoyama et al. 2000), and the sea level had greatly fallen (Fleming et al. 1998). During this period, as a result of the East Asian monsoon, the permafrost line in Eastern China in 20 ka BP moved southwards for five latitudes from current one, and Y. Si Á B. Li (&) Á X. Wen Á D. Niu School of Geographical Science, South China Normal University, Guangzhou 510631, China e-mail: libsh2013@163.com; libsh@scnu.edu.cn B. Li State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061, China D. D. Zhang Department of Geography, University of Hong Kong, Pokfulam Road, Hong Kong, China F. Wang Tourism Department, Huizhou University, Huizhou 516007, China S. Du Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510630, China Y. Guo Guangzhou Institute of Geography, Guangzhou 510070, China 123 Environ Earth Sci DOI 10.1007/s12665-014-3352-0