气候变化领域集成服务门户(CCPortal): Spatial-seasonal patterns reveal large-scale atmospheric controls on Asian Monsoon precipitation water isotope ratios

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DOI	10.1016/j.epsl.2018.09.028
	Spatial-seasonal patterns reveal large-scale atmospheric controls on Asian Monsoon precipitation water isotope ratios
	Cai, Zhongyin; Tian, Lide; Bowen, Gabriel J.
通讯作者	Cai, ZY ; Tian, LD (通讯作者)
发表日期	2018
ISSN	0012-821X
EISSN	1385-013X
起始页码	158
结束页码	169
卷号	503
英文摘要	Correlated seasonal variation in precipitation amount and its oxygen isotope ratios (delta O-18) has long been observed and frequently invoked in the interpretation of paleo-delta O-18 records from the Asian Monsoon (AM) region. However, the underlying cause of the observed seasonal delta O-18 variation is still under debate. Precipitation delta O-18 values show a single, consistent seasonal pattern across the region, with high values in pre-monsoon (late-spring to early-summer) and low values in the monsoon mature (mid- to late summer) periods. We tested three hypotheses that may give rise to the measured precipitation 3180 pattern, involving variation in: 1) local precipitation, 2) moisture sources, and 3) convection in moisture source regions. We show that seasonal precipitation amounts across the AM region exhibit two pattern types: pre-monsoon peak or monsoon mature peak, and thus do not provide a consistent explanation for the isotopic pattern. We test the hypotheses that changing moisture sources or moisture source isotope ratios drive the seasonal isotopic pattern using a combination of Lagrangian moisture source attribution and output from an isotope-enabled General Circulation Model (LMDZ4), but find little seasonal variation in moisture sources; that which does exist is not consistent with the observed isotopic change. Instead, we show that the precipitation delta O-18 transition from pre-monsoon to monsoon mature stage is correlated with intensification of convective activity in moisture source regions, which is the result of monsoon establishment and northward migration of the Intertropical Convergence Zone (ITCZ). We propose that light water vapor, transferred to the lower-troposphere through downdrafts and evaporation of rain in the vicinity of intense convection, is advected to the AM region and labels precipitation during the monsoon mature period. These results demonstrate that precipitation delta O-18 in the AM region more strongly reflect large-scale atmospheric dynamics than local precipitation amount or moisture source, guiding the interpretation of paleo-isotope data from this region. (C) 2018 Elsevier B.V. All rights reserved.
关键词	SUMMER MONSOON MOISTURE SOURCES OXYGEN ISOTOPES STABLE-ISOTOPES ICE CORES DELTA-D REGION CHINA CONVECTION RESOLUTION
英文关键词	oxygen isotope; precipitation; seasonal variation; moisture source; convection; Asian monsoon
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000449246100016
来源期刊	EARTH AND PLANETARY SCIENCE LETTERS
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/259304
推荐引用方式 GB/T 7714	Cai, Zhongyin,Tian, Lide,Bowen, Gabriel J.. Spatial-seasonal patterns reveal large-scale atmospheric controls on Asian Monsoon precipitation water isotope ratios[J]. 中国科学院青藏高原研究所,2018,503.
APA	Cai, Zhongyin,Tian, Lide,&Bowen, Gabriel J..(2018).Spatial-seasonal patterns reveal large-scale atmospheric controls on Asian Monsoon precipitation water isotope ratios.EARTH AND PLANETARY SCIENCE LETTERS,503.
MLA	Cai, Zhongyin,et al."Spatial-seasonal patterns reveal large-scale atmospheric controls on Asian Monsoon precipitation water isotope ratios".EARTH AND PLANETARY SCIENCE LETTERS 503(2018).