Abstract
The paleoclimate application of speleothem δ13C is influenced by site-specific processes. Here we present four stalagmite δ13C records from two caves in southern China, covering early and late Marine Isotope Stage (MIS) 3 and the Holocene, to investigate the spatio-temporal pattern of calcite δ13C changes and the relationship with Asian monsoon (AM) variability. In each growth period, precessional- to millennial-scale changes are clear in the δ18O record. In contrast, millennial variability is absent in the δ13C record, which characterizes persistent centennial oscillations. However, centennial-scale δ18O variations agree well with those of δ13C, with a larger amplitude in δ13C changes (about twice that of δ18O). This suggests that soil humidity balance associated with regional hydrological circulations is important for these centennial δ13C changes, although evaporation-related kinetic fractionation can induce concurrent enrichments in δ18O and δ13C. In frequency, the detrended δ18O and δ13C records are coupled at a periodicity of about 300 yr during the last glacial period and 150 yr during the Holocene. Those centennial-scale δ13C variations are generally consistent with Greenland temperature variability, indicating a climate response over broad regions. Thus, strong co-variation of δ18O and δ13C records should have a climatic origin, even if it is amplified by kinetic effects.
Original language | English (US) |
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Pages (from-to) | 333-346 |
Number of pages | 14 |
Journal | Quaternary Research (United States) |
Volume | 85 |
Issue number | 3 |
DOIs | |
State | Published - May 1 2016 |
Bibliographical note
Funding Information:We are grateful to two anonymous reviewers for their critical and instructive comments. This work was jointly supported by grants of National Nature Science Foundation of China (No. 41172148 , 41130210 , 41172314 , 41230524 , 41172165 ), NBRP (No. 2013CB955902 ), A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) , Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application , and Key Laboratory of Virtual Geographic Environment (Nanjing Normal University) .
Publisher Copyright:
© 2016 University of Washington
Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
Keywords
- Centennial-scale AM variability
- Soil processes
- Speleothem δC
- Wulu and Dongge caves