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DOI	10.1007/s00382-018-4582-8
	Causes and evolution of the southeastern tropical Atlantic warm event in early 2016
	Lübbecke J.F.; Brandt P.; Dengler M.; Kopte R.; Lüdke J.; Richter I.; Sena Martins M.; Tchipalanga P.C.M.
发表日期	2019
ISSN	0930-7575
起始页码	261
结束页码	274
卷号	53 期号:2020-01-02
英文摘要	A strong warm event occurred in the southeastern tropical Atlantic Ocean off Angola and Namibia in January and February 2016 with sea surface temperature anomalies reaching 3 °C. In contrast to classical Benguela Niño events, the analysis of various direct observations indicates that the warming was not predominantly forced by an equatorial Kelvin wave exciting a coastally trapped wave but instead resulted from a combination of local processes that are related to (1) a weakening of the alongshore, i.e. mainly southerly, winds and (2) enhanced freshwater input through local precipitation and river discharge. Consistent with the weakened winds, we find a reduction in latent heat loss from the ocean and a poleward surface current anomaly. The surface freshening, which is detected in satellite observations of sea surface salinity, caused a very shallow mixed layer and enhanced upper ocean stratification. This is supported by the analysis of the velocity structure of the Angola Current at 11°S, which shows that at the time of the event subsurface velocities were directed northward while surface velocities were directed southward. The shallow layer of warm and fresh surface water was thus advected poleward by the surface current. In addition, a reduction of the local upwelling and the formation of a barrier layer that inhibits the entrainment of cool subsurface waters into the surface mixed layer might have contributed to the warm surface anomaly. The sudden termination of the warm event was accompanied by a re-intensification of southerly winds in March. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Benguela Niño; Interannual variability; Sea surface temperature anomalies; Tropical Atlantic Ocean
语种	英语
scopus关键词	annual variation; Kelvin wave; mixed layer; sea surface salinity; sea surface temperature; stratification; temperature anomaly; upper ocean; warming; Angola; Atlantic Ocean; Atlantic Ocean (Tropical); Namibia
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/146208
作者单位	GEOMAR Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, Kiel, 24105, Germany; Christian-Albrechts-Universität zu Kiel, Kiel, Germany; Application Laboratory, JAMSTEC, Yokohama, Japan; University of Hamburg, Hamburg, Germany; Instituto Nacional de Investigacaõ Pesqueira (INIP), Moçâmedes, Angola
推荐引用方式 GB/T 7714	Lübbecke J.F.,Brandt P.,Dengler M.,et al. Causes and evolution of the southeastern tropical Atlantic warm event in early 2016[J],2019,53(2020-01-02).
APA	Lübbecke J.F..,Brandt P..,Dengler M..,Kopte R..,Lüdke J..,...&Tchipalanga P.C.M..(2019).Causes and evolution of the southeastern tropical Atlantic warm event in early 2016.Climate Dynamics,53(2020-01-02).
MLA	Lübbecke J.F.,et al."Causes and evolution of the southeastern tropical Atlantic warm event in early 2016".Climate Dynamics 53.2020-01-02(2019).