Impact of South Pacific Subtropical Dipole Mode on the Equatorial Pacific

doi:10.1175/JCLI-D-17-0256.1

	Impact of South Pacific Subtropical Dipole Mode on the Equatorial Pacific
	Zheng, Jian 1,2; Wang, Faming 1,2,3; Alexander, Michael A.4; Wang, Mengyang 1,3
刊名	JOURNAL OF CLIMATE
	2018-03-01
卷号	31 期号:6 页码:2197-2216
ISSN号	0894-8755
DOI	10.1175/JCLI-D-17-0256.1
文献子类	Article
英文摘要	Previous studies have indicated that a sea surface temperature anomaly (SSTA) dipole in the subtropical South Pacific (SPSD), which peaks in austral summer (January-March), is dominated by thermodynamic processes. Observational analyses and numerical experiments were used to investigate the influence of SPSD mode on the equatorial Pacific. The model is an atmospheric general circulation model coupled to a reduced-gravity ocean model. An SPSD-like SSTA was imposed on 1 March, after which the model was free to evolve until the end of the year. The coupled model response showed that warm SSTAs extend toward the equator with northwesterly wind anomalies and then grow to El Nino-like anomalies by the end of the year. SPSD forcing weakens southeasterly trade winds and propagates warm SSTAs toward the equator through wind-evaporation-SST (WES) feedback. Meanwhile, relaxation of trade winds in the eastern equatorial Pacific depresses the thermocline and upwelling. Eastward anomalous currents near the equator cause warm horizontal advection in the central Pacific. Further experiments showed that thermodynamic coupling mainly acts on but is not essential for SSTA propagation, either from the subtropics to the equator or westward along the equator, while oceanic dynamic coupling alone also appears to be able to initiate anomalies on the equator and plays a critical role in SSTA growth in the tropical Pacific. This is consistent with observational analyses, which indicated that influence of WES feedback on SSTA propagation associated with the SPSD is limited. Finally, the warm pole close to the equator plays the dominant role in inducing the El Nino-like anomalies.
WOS关键词	EL-NINO ; SURFACE-TEMPERATURE ; ATMOSPHERE MODEL ; MERIDIONAL MODE ; OCEAN ; VARIABILITY ; TELECONNECTIONS ; OSCILLATION ; REANALYSIS ; MECHANISM
WOS研究方向	Meteorology & Atmospheric Sciences
语种	英语
出版者	AMER METEOROLOGICAL SOC
WOS记录号	WOS:000427447000007
资助机构	Chinese Academy of Sciences(XDA11010102) ; Natural Science Foundation of China(41606018 ; Funds for Creative Research Groups of China(41421005) ; NSFC-Shandong Joint Fund for Marine Science Research Centers(U1406402) ; 41776035)
内容类型	期刊论文
源URL	[http://ir.qibebt.ac.cn/handle/337004/10715]
专题	中国科学院青岛生物能源与过程研究所
通讯作者	Zheng, Jian
作者单位	1.Chinese Acad Sci, Inst Oceanol, Key Lab Ocean Circulat & Waves, Qingdao, Peoples R China 2.Qingdao Natl Lab Marine Sci & Technol, Lab Ocean & Climate Dynam, Qingdao, Peoples R China 3.Univ Chinese Acad Sci, Beijing, Peoples R China 4.NOAA, Earth Syst Res Lab, Boulder, CO USA
推荐引用方式 GB/T 7714	Zheng, Jian,Wang, Faming,Alexander, Michael A.,et al. Impact of South Pacific Subtropical Dipole Mode on the Equatorial Pacific[J]. JOURNAL OF CLIMATE,2018,31(6):2197-2216.
APA	Zheng, Jian,Wang, Faming,Alexander, Michael A.,&Wang, Mengyang.(2018).Impact of South Pacific Subtropical Dipole Mode on the Equatorial Pacific.JOURNAL OF CLIMATE,31(6),2197-2216.
MLA	Zheng, Jian,et al."Impact of South Pacific Subtropical Dipole Mode on the Equatorial Pacific".JOURNAL OF CLIMATE 31.6(2018):2197-2216.