气候变化领域集成服务门户(CCPortal): The North Atlantic as a driver of summer atmospheric circulation

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DOI	10.1175/JCLI-D-19-0423.1
	The North Atlantic as a driver of summer atmospheric circulation
	Osborne J.M.; Collins M.; Screen J.A.; Thomson S.I.; Dunstone N.
发表日期	2020
ISSN	0894-8755
起始页码	7335
结束页码	7351
卷号	33 期号:17
英文摘要	Skill in seasonal forecasts in the Northern Hemisphere extratropics is mostly limited to winter. Drivers of summer circulation anomalies over the North Atlantic–European (NAE) sector are poorly understood. Here, we investigate the role of North Atlantic sea surface temperatures (SSTs) in driving summer atmospheric circulation changes. The summer North Atlantic Oscillation (SNAO), the leading mode of observed summer atmospheric circulation variability in the NAE sector, is correlated with a distinct SST tripole pattern in the North Atlantic. An atmospheric general circulation model is used to test whether there are robust atmospheric circulation responses over the NAE sector to concurrent SSTs related to the SNAO. The most robust responses project onto the summer east Atlantic (SEA) pattern, the second dominant mode of observed summer atmospheric circulation variability in the NAE sector, and are most evident at the surface in response to tropical SSTs and at altitude in response to extratropical SSTs. The tropical-to-extratropical teleconnection appears to be due to Rossby wave propagation from SST anomalies, and in turn precipitation anomalies, in the Caribbean region. We identify key biases in the model, which may be responsible for the overly dominant SEA pattern variability, compared to the SNAO, and may also explain why the responses resemble the SEA pattern, rather than the SNAO. Efforts to eradicate these biases, perhaps achieved by higher-resolution simulations or with improved model physics, would allow for an improved understanding of the true response to North Atlantic SST patterns. © 2020 American Meteorological Society.
英文关键词	Atmospheric pressure; Climatology; Mechanical waves; Surface waters; Tropics; Wave propagation; Atmospheric circulation; Atmospheric circulation changes; Atmospheric circulation variability; Atmospheric general circulation models; Circulation anomalies; North Atlantic oscillations; Precipitation anomalies; ROSSBY wave propagation; Oceanography; atmospheric general circulation model; North Atlantic Oscillation; Rossby wave; sea surface temperature; summer; teleconnection; temperature anomaly; Atlantic Ocean; Atlantic Ocean (North)
语种	英语
来源期刊	Journal of Climate
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/171153
作者单位	Met Office, Exeter, United Kingdom; College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, United Kingdom; Met Office Hadley Centre, Exeter, United Kingdom
推荐引用方式 GB/T 7714	Osborne J.M.,Collins M.,Screen J.A.,et al. The North Atlantic as a driver of summer atmospheric circulation[J],2020,33(17).
APA	Osborne J.M.,Collins M.,Screen J.A.,Thomson S.I.,&Dunstone N..(2020).The North Atlantic as a driver of summer atmospheric circulation.Journal of Climate,33(17).
MLA	Osborne J.M.,et al."The North Atlantic as a driver of summer atmospheric circulation".Journal of Climate 33.17(2020).