气候变化领域集成服务门户(CCPortal): Westerlies effect in Holocene paleoclimate records from the central Qinghai-Tibet Plateau

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DOI	10.1016/j.palaeo.2022.111036
	Westerlies effect in Holocene paleoclimate records from the central Qinghai-Tibet Plateau
	Chen, Hao; Zhu, Liping; Hou, Juzhi; Steinman, Byron A.; He, Yue; Brown, Erik T.
通讯作者	Zhu, LP (通讯作者)
发表日期	2022
ISSN	0031-0182
EISSN	1872-616X
卷号	598
英文摘要	Our knowledge of the influence of the Westerlies on the hydroclimate of High Mountain Asia during the Holocene, especially during the mid-Holocene, remains poorly understood, limiting our understanding of the controlling mechanisms of past climate change in this region. Assessing the impact of the westerly winds has proven to be a challenge due to a lack of direct indicators. In this study, we summarize the influence of the Westerlies reflected in Holocene paleoclimate records from the central Qinghai-Tibet Plateau (CQTP). This is the transitional zone of atmospheric circulation where the climate is drier under the influence of westerly winds than under monsoonal influences. We identify two types of Westerlies effect, emerging at 13-11 ka (I) and 7-2 ka (II), and then assess potential circulation mechanisms by examining circulation indices and developing a Westerlies effect index (WEI) in combination with modern observations of precipitation stable isotopes. The WEI integrates signals of two independent environmental indicators, leaf wax delta D from Linggo Co and median grain size from Chibuzhang Co. We observe two types of Westerlies effects: Type I prevailed in the Late Glacial, and Type II occurred under the cool conditions of the mid- to late Holocene (7.0-4.5 ka and 3.5-2.0 ka on the CQTP). During the times of Type II Westerlies effects, circulation affecting regional atmospheric precipitation appears to have shifted from being dominated by the South Asian Summer Monsoon (SASM) to a monsoon-westerly transition state with relatively lower total effective moisture. However, compared with the driest periods (e.g. the Younger Dryas), the westerly jets still brought considerable precipitation, especially in non-monsoon seasons, and even helped to maintain moderate lake water levels. The asynchronous relationship between lake levels (water balance) and atmospheric circulation patterns since ~2.0 ka indicates that air mass source (marine and continental) and trajectory can influence rates of water recycling and/or re-evaporation. This study sheds light on the hydrological processes and environmental dynamics associated with the interplay between the westerly winds and the monsoons on the QTP and indicates that at times during the Holocene the Westerlies played a more prominently role in delivering moisture to the region (especially the transitional zone) than was previously thought.
关键词	STABLE-ISOTOPES ICE-CORE MOISTURE AVAILABILITY ASIAN MONSOON PRECIPITATION LAKE CLIMATE VARIABILITY DELTA-O-18 EVOLUTION
英文关键词	Westerlies effect; Paleoclimate; Holocene; Stable isotopes; Atmospheric circulation; Qinghai-Tibet Plateau
语种	英语
WOS研究方向	Physical Geography ; Geology ; Paleontology
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary ; Paleontology
WOS记录号	WOS:000802919100004
来源期刊	PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
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/260713
推荐引用方式 GB/T 7714	Chen, Hao,Zhu, Liping,Hou, Juzhi,et al. Westerlies effect in Holocene paleoclimate records from the central Qinghai-Tibet Plateau[J]. 中国科学院青藏高原研究所,2022,598.
APA	Chen, Hao,Zhu, Liping,Hou, Juzhi,Steinman, Byron A.,He, Yue,&Brown, Erik T..(2022).Westerlies effect in Holocene paleoclimate records from the central Qinghai-Tibet Plateau.PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY,598.
MLA	Chen, Hao,et al."Westerlies effect in Holocene paleoclimate records from the central Qinghai-Tibet Plateau".PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY 598(2022).