Quaternary upper ocean thermal gradient variations in the South China Sea: Implications for east Asian monsoon climate

doi:10.1029/2004PA001115

	Quaternary upper ocean thermal gradient variations in the South China Sea: Implications for east Asian monsoon climate
	Tian, J ; Wang, PX ; Chen, RH ; Cheng, XR
刊名	PALEOCEANOGRAPHY
	2005-10-26
卷号	20 期号:4
ISSN号	0883-8305
DOI	10.1029/2004PA001115
文献子类	Article
英文摘要	The east Asian monsoon climate has an overwhelming influence on local climatic conditions of the South China Sea (SCS). Here we present results from a 3-year study of modern sediment traps from the central SCS in which the percentage of opal, the fluxes of Pulleniatina obliquiloculata and Globigerinoides ruber, the organic carbon flux, and primary productivity all show highest values during winter when the mixed layer depth is deepest. The delta(18)O difference (Delta delta(18)O((P-G))) between the subsurface dwelling P. obliquiloculata and the mixed layer dwelling G. ruber in core top samples from 12 piston cores and one Ocean Drilling Program (ODP) site in the SCS is large, similar to 0.6 parts per thousand in a cold eddy area with a shallow mixed layer off Vietnam, but is reduced in deep mixed layer settings lacking cold eddies. We also present 1.56 Myr-long isotope records of G. ruber and P. obliquiloculata from ODP site 1143 in the southern SCS that reveal upper ocean thermal gradient variations during the Quaternary. Lower Delta delta(18)O((P-G)) values indicate increased mixed layer depths over most glacial episodes, likely due to stronger winter monsoon winds. In contrast, higher Delta delta(18)O((P-G)) values during interglacial intervals suggest decreased mixed layer depths and thus weaker winter monsoon winds. Comparisons of Delta delta(18)O((P-G)) with the percentage of P. obliquiloculata at site 1143 and the percentage of herbs and opal flux at site 1144 demonstrate that glacial-interglacial variations were strongly influenced by stronger and weaker east Asian winter monsoons during glacials and interglacials, respectively. Therefore the upper ocean thermal gradient variations in the SCS have been consistently affected by the east Asian winter monsoon since at least the beginning of the Pleistocene.
WOS关键词	PLANKTONIC-FORAMINIFERA ; SULU-SEA ; EQUATORIAL PACIFIC ; ATLANTIC ; RECORD ; DEGLACIATION ; VARIABILITY ; PLEISTOCENE ; POLLEN ; SYSTEM
WOS研究方向	Geology ; Oceanography ; Paleontology
语种	英语
出版者	AMER GEOPHYSICAL UNION
WOS记录号	WOS:000233110700001
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/65787]
专题	中国科学院地质与地球物理研究所
通讯作者	Tian, J
作者单位	1.Tongji Univ, State Key Lab Marine Geol, Shanghai 200092, Peoples R China 2.Chinese Acad Sci, Inst Geol & Geophys, Beijing, Peoples R China 3.State Ocean Adm, Key Lab Submarine Geosci, Hangzhou 310012, Peoples R China
推荐引用方式 GB/T 7714	Tian, J,Wang, PX,Chen, RH,et al. Quaternary upper ocean thermal gradient variations in the South China Sea: Implications for east Asian monsoon climate[J]. PALEOCEANOGRAPHY,2005,20(4).
APA	Tian, J,Wang, PX,Chen, RH,&Cheng, XR.(2005).Quaternary upper ocean thermal gradient variations in the South China Sea: Implications for east Asian monsoon climate.PALEOCEANOGRAPHY,20(4).
MLA	Tian, J,et al."Quaternary upper ocean thermal gradient variations in the South China Sea: Implications for east Asian monsoon climate".PALEOCEANOGRAPHY 20.4(2005).