A full-spectrum characterization of past interglacial climate is a necessary prerequisite for the detection and attribution of climate changes during the current interglacial. Here we present a speleothem record of Asian summer monsoon (ASM) during Marine Isotope Stage (MIS) 11 interglacial (MIS 11c), from Yongxing cave, China. The record's unprecedented chronologic constraints and decadal-scale temporal resolution allow a precise and direct comparison of ASM between the MIS 11c and the Holocene. Our data suggest that orbital-centennial patterns of ASM were remarkably similar during both interglacial, including their pacing and structure. Notably, a multi-millennial stronger monsoon late in MIS 11c, the “Late-MIS 11c shift,” is similar to the Late Holocene strengthening of the ASM, the “2-Kyr shift.” Thus, the multicentennial ASM weakening at the end of the Late-MIS 11c shift could imply that the current century-long ASM waning trend may persist into the future, if only natural forcings are considered.
Bibliographical noteFunding Information:
This work was supported by China's NSFC grants 41888101, 41731174, 41230524, 4157020432 and 41561144003 and U.S. NSF grant 1702816. H. C. designed the research and experiments; S. T. C. and X. G. K. collected the samples. X. N. Z., H. C., and Y. F. N. performed all stable isotope measurements and 230Th dating work. X. N. Z. counted the annual bands by using Confocal Laser Fluorescent Microscopy. X. N. Z., A. S., and H. C. did the data analyses. H. C., X. N. Z., and A. S. wrote the manuscript, which was edited by all of the coauthors. The authors declare no competing financial interests. We thank X. L. Q from State key laboratory for manufacturing system engineering, Xi'an Jiaotong University for technical support. Speleothem data in this research are available in Table?S2 and online reference (http://doi.org/10.5281/zenodo.3365932).
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