DOI: 10.1175/JCLI-D-11-00150.1
Scopus记录号: 2-s2.0-84856969727
论文题名: A strong atlantic meridional mode event in 2009: The role of mixed: Layer dynamics
作者: Foltz G.R. ; McPhaden M.J. ; Lumpkin R.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2012
卷: 25, 期: 1 起始页码: 363
结束页码: 380
语种: 英语
Scopus关键词: Atlantic Ocean
; Atmosphere-ocean interactions
; Climate variability
; Oceanic mixed layers
; Sea surface temperatures
; Atmospheric temperature
; Climatology
; Dynamics
; Heat flux
; Oceanography
; Strengthening (metal)
; Tropics
; Wind
; air-sea interaction
; climate feedback
; climate variation
; cooling
; downwelling
; flooding
; heat flux
; high pressure system
; intertropical convergence zone
; meridional circulation
; mixed layer
; sea surface temperature
; temperature anomaly
; temperature gradient
; trade wind
; upwelling
; Atlantic Ocean
; Atlantic Ocean (North)
; Atlantic Ocean (South)
; Brazil
; Ena
英文摘要: In the first half of 2009, anomalous cooling of sea surface temperatures (SSTs) in the equatorial North Atlantic (ENA; 28-128N) triggered a strong Atlantic meridional mode event. During its peak in April-May, SSTs in the ENA were 18C colder than normal and SSTs in the equatorial South Atlantic (58S-08) were 0.58C warmer than normal. Associated with the SST gradient were anomalous northerly winds, an anomalous southward shift of the intertropical convergence zone, and severe flooding in Northeast Brazil. This study uses in situ and satellite observations to examine the mechanisms responsible for the anomalous cooling in the ENAduring boreal winter and spring of 2009. It is found that the cooling was initiated by stronger than normal trade winds during January and February 2009 associated with an anomalous strengthening of the subtropical North Atlantic high pressure system. Between 68 and 128N, unusually strong trade winds cooled the ocean through wind-induced evaporation and deepened the mixed layer anomalously by 5-20 m. Closer to the equator, surface equatorial winds responded to the anomalous interhemispheric SST gradient, becoming northwesterly between the equator and 68N. The anomalous winds drove upwelling of 0.5-1 m day21 during March-April, a period when there is normally weak downwelling. The associated vertical turbulent heat flux at the base of the mixed layer led to unusually cool SSTs in the central basin, further strengthening the anomalous interhemispheric SST gradient. These results emphasize the importance of mixed layer dynamics in the evolution of the meridional mode event of 2009 and the potential for positive coupled feedbacks between wind-induced upwelling and SST in the ENA. © 2012 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/52592
Appears in Collections: 气候变化事实与影响
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作者单位: NOAA/Atlantic Oceanographic and Meteorological Laboratory, Miami, FL, United States; NOAA/Pacific Marine Environmental Laboratory, Seattle, WA, United States
Recommended Citation:
Foltz G.R.,McPhaden M.J.,Lumpkin R.. A strong atlantic meridional mode event in 2009: The role of mixed: Layer dynamics[J]. Journal of Climate,2012-01-01,25(1)