Climate Variability in Shennongjia During the Last Interglacial Inferred from a High-resolution Stalagmite Record

Speleothem studies have the potential to considerably improve our knowledge of climate changes of the past 500 000 a.Above all,this is due to the independent and reliable calendar year chronology provided by uranium-series dating techniques and to the multitude of paleoclimate proxy records preserved in speleothems.Here we present an absolute-dated and high-resolution stable oxygen record from a stalagmite(No.YX21)in Yongxing Cave,Shennongjia natural reservation,central China,giving the details on climatic fluctuations during the Last Interglacial periods.Based on 4 230Th dates and 303 oxygen isotope data,an averaged 8 a East Asian Monsoon precipitation series was established through 127.32 to 124.95 thousand years before present(ka BP).This detailed record uncovered that the δ18O have the high-frequency variability characteristic,indicating the instability of the East Asian Monsoon during the Last Interglacial.During this interval,the YX21 record has 4 Asian Monsoon weak events,possibly related to the interglacial ice-rafting events in the North Atlantic.Power spectral analysis of the record shows statistically significant periodicities centered on 661 a,127 a,118 a,19~22 a.These periodicities are close to significant periods of the δ14C record,indicates that solar changes are also responsible for changes of Asian Monsoon intensity.