气候变化领域集成服务门户(CCPortal): Quantifying atmosphere and ocean origins of North American precipitation variability

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DOI	10.1007/s00382-021-05685-0
	Quantifying atmosphere and ocean origins of North American precipitation variability
	Zhang H.; Seager R.; He J.; Diao H.; Pascale S.
发表日期	2021
ISSN	0930-7575
起始页码	1145
结束页码	1162
卷号	56 期号:2021-11-12
英文摘要	How atmospheric and oceanic processes control North American precipitation variability has been extensively investigated, and yet debates remain. Here we address this question in a 50 km-resolution flux-adjusted global climate model. The high spatial resolution and flux adjustment greatly improve the model’s ability to realistically simulate North American precipitation, the relevant tropical and midlatitude variability and their teleconnections. Comparing two millennium-long simulations with and without an interactive ocean, we find that the leading modes of North American precipitation variability on seasonal and longer timescales exhibit nearly identical spatial and spectral characteristics, explained fraction of total variance and associated atmospheric circulation. This finding suggests that these leading modes arise from internal atmospheric dynamics and atmosphere-land coupling. However, in the fully coupled simulation, North American precipitation variability still correlates significantly with tropical ocean variability, consistent with observations and prior literature. We find that tropical ocean variability does not create its own type of atmospheric variability but excites internal atmospheric modes of variability in midlatitudes. This oceanic impact on North American precipitation is secondary to atmospheric impacts based on correlation. However, relative to the simulation without an interactive ocean, the fully coupled simulation amplifies precipitation variance over southwest North America (SWNA) during late spring to summer by up to 90%. The amplification is caused by a stronger variability in atmospheric moisture content that is attributed to tropical Pacific sea surface temperature variability. Enhanced atmospheric moisture variations over the tropical Pacific are transported by seasonal mean southwesterly winds into SWNA, resulting in larger precipitation variance. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/183257
作者单位	Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States; School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, United States; Yau Mathematical Sciences Center, Tsinghua University, Beijing, China; Department of Earth System Science, Stanford University, Stanford, CA, United States
推荐引用方式 GB/T 7714	Zhang H.,Seager R.,He J.,et al. Quantifying atmosphere and ocean origins of North American precipitation variability[J],2021,56(2021-11-12).
APA	Zhang H.,Seager R.,He J.,Diao H.,&Pascale S..(2021).Quantifying atmosphere and ocean origins of North American precipitation variability.Climate Dynamics,56(2021-11-12).
MLA	Zhang H.,et al."Quantifying atmosphere and ocean origins of North American precipitation variability".Climate Dynamics 56.2021-11-12(2021).