Abstract:
230Th ages and oxygen isotope data of a stalagmite from Shanbao Cave in Hubei Province characterize the East Asian Monsoon precipitation from 140 to 124 kaBP. The record broadly follows 33°N summer insolation. Similar changing trend was observed in the two δ
18O curves derived from the Shanbao Cave and Dongge Cave, which proved the changes of the oxygen composition of the Asian Monsoon precipitation have the generally regional meanings. During the Last Interglacial period (129.5~124.3 kaBP), SB28 δ
18O record shows high frequency fluctuation. Power spectral analysis of the record shows statistically significant centennial periodicities centered on 525, 228 and 207 a. These periodicities are close to significant periods of the △
14C record, indicating that solar changes are also responsible for changes of Asian Monsoon intensity. During the transition from the Penultimate Glaciation to the Last Interglaciation, the North Hemisphere insolation possible triggers the inception of full interglacial conditions worldwide.