气候变化领域集成服务门户(CCPortal): Migration of the Northern Boundary of the East Asian Summer Monsoon Over the Last 21,000 years

CCPortal

DOI	10.1029/2021JD035078
	Migration of the Northern Boundary of the East Asian Summer Monsoon Over the Last 21,000 years
	Wu B.; Lang X.; Jiang D.
发表日期	2021
ISSN	2169-897X
卷号	126 期号:17
英文摘要	Investigating the past evolution of the northern boundary of the East Asian summer monsoon (EASM) is important in understanding the East Asian climate of the past, present, and future. In this study, using a set of transient simulations from TraCE-21ka, we investigate the migration of the EASM northern boundary over eastern China via three metrics and its responses to individual external forcings during the last 21,000 years. The northern boundary was located farther southeastward from 21 ka to 18 ka and more northwestward since 15 ka compared with the present boundary. For two key time slices, the boundary exhibited a southeastward migration ranging from 120 to 140 km in the last glacial maximum (LGM) and a 110–140 km northwestward shift in the mid-Holocene relative to the present boundary. Temporally, the evolution of the boundary was characterized first by a poleward migration and then an equatorward shift from the LGM to the present, which was mainly driven by orbital insolation. This long-term trend was punctuated by several millennial fluctuations in response to meltwater fluxes. The boundary migration during the LGM and the mid-Holocene generally lies within the range of the multimodel results from the Paleoclimate Modeling Intercomparison Project Phase 4 (PMIP4). In terms of dynamic mechanisms, an orbitally induced increase of summer insolation led to an enhanced land-sea thermal contrast between the East Asian continent and adjacent ocean and, in turn, intensified low-level southerly winds, which facilitated the northwestward migration of the EASM northern boundary and more precipitation over eastern China. The boundary responses to the changing meltwater fluxes were similar but weak. Additionally, the EASM northern limit was closely linked to the forest-steppe boundary. The reconstructed forest-steppe boundary estimated from pollen records and the simulated EASM northern edge display spatially consistent positions, orientations, and change trends. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	Eastern China; Northern boundary of the East Asian summer monsoon; TraCE-21ka
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/237021
作者单位	Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China; College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China; Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China
推荐引用方式 GB/T 7714	Wu B.,Lang X.,Jiang D.. Migration of the Northern Boundary of the East Asian Summer Monsoon Over the Last 21,000 years[J],2021,126(17).
APA	Wu B.,Lang X.,&Jiang D..(2021).Migration of the Northern Boundary of the East Asian Summer Monsoon Over the Last 21,000 years.Journal of Geophysical Research: Atmospheres,126(17).
MLA	Wu B.,et al."Migration of the Northern Boundary of the East Asian Summer Monsoon Over the Last 21,000 years".Journal of Geophysical Research: Atmospheres 126.17(2021).