A possible Younger Dryas-type event during Asian monsoonal Termination 3

• Published in: Science China. Earth sciences Vol. 49; no. 9; pp. 982 - 990
• Main Authors: Chen, Shitao, Wang, Yongjin, Kong, Xinggong, Liu, Dianbing, Cheng, Hai, Edwards, R. L.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01.09.2006; College of Geography Science, Nanjing Normal University, Jiangsu Key Laboratory of Environmental Change and Ecological Construction, Nanjing 210097, China%Department of Geology and Geophysics, University of Minnesota, Minneapolis MN55455, USA
• Subjects: Asian; Asian monsoons; Caves; Deglaciation; Elevation; event; Hubei; Interglacial periods; monsoon; Monsoons; Precipitation; Province; Shennongjia; stalagmite; Termination; Wind; YD-type; China, People's Rep., Jiangsu Prov., Nanjing; INW, China, People's Rep., Jiangsu Prov; China, People's Rep., Hubei Prov; China, People's Rep., Guizhou Prov; stalagmite; Shennongjia; Termination 3; YD-type event; Hubei Province; Asian monsoon
• ISSN: 1674-7313; 1006-9313; 1869-1897; 1862-2801
• DOI: 10.1007/s11430-006-0982-4

Seven U-Th dates, 560 δ18O data and microscopic sequences were measured for stalagmites from two high-altitude caves in Shennongjia area, Hubei Province. Variations of the decadal-resolution stalagmite δ18O record from Swan Cave (1600 m elevation) reflect large spatial changes in circulation strength and precipitation of Asian monsoon. The evidence comes from a great similarity among the stalagmite δ18O records from Nanjing, Jiangsu Province; Libo, Guizhou Province and here studied area during the last deglaciation, including a part interval of Younger-Dryas event and Bolling-Allerod. A 30-year-resolution stalagmite δ18O record from Yongxing Cave (1400 m elevation), 70 km away from Swan Cave, reveals a rapid transition of Asian monsoon climate during Termination 3 at about 245±5 kaBP. Based on 3 U-Th dates and about 5000 continuous annual bands, a millennial dry episode has been observed during Asian monsoonal Termination 3 from the Yongxing δ18O profile. With respect to its structure, duration and transition, the dry reversal, as indicated by our stalagmite δ18O record, generally agrees with the pattern of the YD event well-expressed in the Chinese stalagmite δ18O records. This YD-type event is characterized by a large decrease in δ18O value as much as 2.30‰, more than half of the δ18O excursion between glacial/interglacial periods, and lasts 1371±59 a determined by the annual counting chronology. After this event, the monsoon climate shifted abruptly into the interglacial period within 74±4 a. Our data corroborate the view that the repeated occurrence of YD-type event was not an "accident", possibly resulted from the coupling of ice-sheet and oceanic/atmospheric circulations.