Summary: | Thorium-230 ages and oxygen isotope ratios of stalagmites from Dongge Cave, China, characterize the Asian Monsoon and low-latitude precipitation over the past 160,000 years. Numerous abrupt changes in O-18/O-16 values result from changes in tropical and subtropical precipitation driven by insolation and millennial-scale circulation shifts. The Last Interglacial Monsoon lasted 9.7+/-1.1 thousand years, beginning with an abrupt (less than 200 years) drop in O-18/O-16 values 129.3+/-0.9 thousand years ago and ending with an abrupt (less than 300 years) rise in O-18/O-16 values 119.6+/-0.6 thousand years ago. The start coincides with insolation rise and measures of full interglacial conditions, indicating that insolation triggered the final rise to full interglacial conditions.
|