气候变化领域集成服务门户(CCPortal): Seasonal wet-dry variability of the Asian monsoon since the middle Pleistocene

CCPortal

DOI	10.1016/j.quascirev.2020.106568
	Seasonal wet-dry variability of the Asian monsoon since the middle Pleistocene
	Wang, Xin; Dettman, David L.; Wang, Mi; Zhang, Jinhui; Saito, Yoshiki; Quade, Jay; Feng, Song; Liu, Jianbao; Chen, Fahu
通讯作者	Wang, X (通讯作者)
发表日期	2020
ISSN	0277-3791
卷号	247
英文摘要	Wet summers and dry winters are an essential feature of monsoon climates, but quantification of change in wet-dry seasonality through time is very challenging because most geological materials fail to record sub-annual environmental signals, instead integrating years, decades, or centuries. Here we quantify Asian wet-dry seasonality since the middle Pleistocene for monsoon climates using high-resolution stable oxygen isotope analysis of land snail shells from the Chinese Loess Plateau. This approach allows us to collect data on single seasons and years in geologic history. Modern shells show that: 1) the delta O-18(shell) values are higher in boreal winter (dry) seasons and lower in boreal summer (wet) seasons; 2) winter - summer differences in delta O-18(shell) (up to 19.2 parts per thousand) are much larger than that expected from seasonal temperature variation; and 3) the delta O-18(shell) range (the difference between the most positive and the most negative values) within a shell records the degree of evaporation of snail body water in the dry season, combined with a rainfall delta O-18/temperature indicator in the wet season. This range can be used as a wetdry seasonality proxy index, although clearly more work is required to calibrate this index. delta O-18(shell) ranges in glacial loess strata (mean = 13.6 parts per thousand) are systematically larger than those from interglacial paleosol layers (mean = 8.6 parts per thousand), suggesting that a significant difference in winter aridity was present, with drier winters in glacial periods and wetter winters in interglacial periods since the middle Pleistocene. This pattern may have been modified by the intrusion of the westerlies into the region in glacial dry seasons. Summer minimum delta O-18(shell) values are similar throughout the record, which contrasts significantly with glacial/interglacial speleothem records, especially if these represent typical monsoon stable isotope patterns in rains. However, if some moisture from the westerlies contribute more negative delta O-18 values in glacial intervals, these minimum delta(18)O( )values may not contradict the patterns seen in the speleothem record. Future work should focus on the seasonal timing of the isotope cycles in land snail shells. (C) 2020 The Author(s). Published by Elsevier Ltd.
关键词	STABLE-ISOTOPE COMPOSITION LAND SNAIL SHELLS LAST GLACIAL MAXIMUM OXYGEN-ISOTOPE SUMMER MONSOON INTERANNUAL VARIABILITY NORTHWESTWARD MIGRATION CLUMPED ISOTOPES TIBETAN PLATEAU NORTH-ATLANTIC
英文关键词	Seasonality; Asian monsoon; Oxygen isotopes; Land Snails; Pleistocene
语种	英语
WOS研究方向	Physical Geography ; Geology
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary
WOS记录号	WOS:000581521700014
来源期刊	QUATERNARY SCIENCE REVIEWS
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/260054
推荐引用方式 GB/T 7714	Wang, Xin,Dettman, David L.,Wang, Mi,et al. Seasonal wet-dry variability of the Asian monsoon since the middle Pleistocene[J]. 中国科学院青藏高原研究所,2020,247.
APA	Wang, Xin.,Dettman, David L..,Wang, Mi.,Zhang, Jinhui.,Saito, Yoshiki.,...&Chen, Fahu.(2020).Seasonal wet-dry variability of the Asian monsoon since the middle Pleistocene.QUATERNARY SCIENCE REVIEWS,247.
MLA	Wang, Xin,et al."Seasonal wet-dry variability of the Asian monsoon since the middle Pleistocene".QUATERNARY SCIENCE REVIEWS 247(2020).