气候变化领域集成服务门户(CCPortal): Testing the trade wind charging mechanism and its influence on ENSO variability

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DOI	10.1175/JCLI-D-19-0727.1
	Testing the trade wind charging mechanism and its influence on ENSO variability
	Chakravorty S.; Perez R.C.; Anderson B.T.; Giese B.S.; Larson S.M.; Pivotti V.
发表日期	2020
ISSN	0894-8755
起始页码	7391
结束页码	7411
卷号	33 期号:17
英文摘要	During the positive phase of the North Pacific Oscillation, westerly wind anomalies over the subtropical North Pacific substantially increase subsurface heat content along the equator by ‘‘trade wind charging’’ (TWC). TWC provides a direct pathway between extratropical atmospheric circulation and El Niño–Southern Oscillation (ENSO) initiation. Previous model studies of this mechanism lacked the ocean–atmospheric coupling needed for ENSO growth, so it is crucial to examine whether TWC-induced heat content anomalies develop into ENSO events in a coupled model. Here, coupled model experiments, forced with TWC favorable (1TWC) or unfavorable (2TWC) wind stress, are used to examine the ENSO response to TWC. The forcing is imposed on the ocean component of the model through the first winter and then the model evolves in a fully coupled configuration through the following winter. The 1TWC (2TWC) forcing consistently charges (discharges) the equatorial Pacific in spring and generates positive (negative) subsurface temperature anomalies. These subsurface temperature anomalies advect eastward and upward along the equatorial thermocline and emerge as like-signed sea surface temperature (SST) anomalies in the eastern Pacific, creating favorable conditions upon which coupled air–sea feedback can act. During the fully coupled stage, warm SST anomalies in 1TWC forced simulations are amplified by coupled feedbacks and lead to El Niño events. However, while 2TWC forcing results in cool SST anomalies, pre-existing warm SST anomalies in the far eastern equatorial Pacific persist and induce local westerly wind anomalies that prevent consistent development of La Niña conditions. While the TWC mechanism provides adequate equatorial heat content to fuel ENSO development, other factors also play a role in determining whether an ENSO event develops. © 2020 American Meteorological Society.
英文关键词	Atmospheric pressure; Climatology; Commerce; Electric charge; Enthalpy; Surface waters; Atmospheric circulation; Atmospheric coupling; Eastern equatorial Pacific; Equatorial heat content; Favorable conditions; Sea surface temperature anomalies; Southern oscillation; Subsurface temperature; Oceanography; atmosphere-ocean coupling; atmospheric circulation; El Nino-Southern Oscillation; sea surface temperature; temperature anomaly; thermocline; trade wind; westerly; Pacific Ocean; Pacific Ocean (East); Pacific Ocean (Equatorial); Pacific 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/171149
作者单位	Cooperative Institute of Marine and Atmospheric Studies, University of Miami, Miami, FL, United States; NOAA Atlantic Oceanographic and Meteorological Laboratory, Miami, FL, United States; Department of Earth and Environment, Boston University, Boston, MA, United States; Department of Oceanography, Texas A&M University, College Station, TX, United States; Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC, United States
推荐引用方式 GB/T 7714	Chakravorty S.,Perez R.C.,Anderson B.T.,et al. Testing the trade wind charging mechanism and its influence on ENSO variability[J],2020,33(17).
APA	Chakravorty S.,Perez R.C.,Anderson B.T.,Giese B.S.,Larson S.M.,&Pivotti V..(2020).Testing the trade wind charging mechanism and its influence on ENSO variability.Journal of Climate,33(17).
MLA	Chakravorty S.,et al."Testing the trade wind charging mechanism and its influence on ENSO variability".Journal of Climate 33.17(2020).