1. A high-resolution stalagmite record of the Holocene East Asian monsoon from Mt Shennongjia, central China.
- Author
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Jinguo Dong, Yongjin Wang, Hai Cheng, Hardt, Ben, Edwards, R. Lawrence, Xinggong Kong, Jiangying Wu, Shitao Chen, Dianbing Liu, Xiuyang Jiang, and Kan Zhao
- Subjects
STALACTITES & stalagmites ,MONSOONS ,INTERTROPICAL convergence zone ,OXYGEN isotopes - Abstract
High-resolution oxygen isotope (δ
18 O) profiles of six stalagmites from Sanbao Cave in Hubei province, central China, established with 1413 oxygen isotope data and 65 230Th ages, provide a continuous history of East Asian Summer Monsoon (EASM) intensity for the period from 13-0.2 thousand years before present (ky BP, relative to AD 1950). The δ18 O record includes four distinct stages in the evolution of the EASM: (1) an abrupt transition (∼11.5 ky BP) into the Holocene; (2) a period of gradual increase in monsoon intensity (11.5-9.5 ky BP); (3) the maximum humid period (9.5-6.5 ky BP); and (4) a period of gradual decline in monsoon intensity (6.5-0.2 ky BP). Comparison of Sanbao with regional records of comparable resolution reveals that the timing of the beginning and end of the Holocene Optimum (as defined by the minimum in δ18 O) was similar in the Indian and East Asian monsoon systems. This supports the idea that shifts in the monsoon tied to shifts in the mean position of the Inter-Tropical Convergence Zone (ITCZ) may control monsoon intensity throughout the entire low-latitude region of Asia on orbital timescales. This observation also supports the idea that the fluctuations in δ18 O recorded across southern Asia reflect broad changes in the monsoon, as opposed to local meteoric precipitation. The EASM records from Sanbao largely follow orbital-scale insolation changes, yet exhibit similar variability to Greenland ice core δ18 O on millennial to centennial scales during the early to middle Holocene (γl = 0.94). [ABSTRACT FROM AUTHOR]- Published
- 2010
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