DOI: 10.1175/JCLI-D-11-00704.1
Scopus记录号: 2-s2.0-84874832075
论文题名: Origin of the intraseasonal variability over the north pacific in boreal summer
作者: Wang L. ; Li T. ; Zhou T. ; Rong X.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2013
卷: 26, 期: 4 起始页码: 1211
结束页码: 1229
语种: 英语
Scopus关键词: Intraseasonal oscillations
; Intraseasonal variability
; Maximum amplitude
; Observational analysis
; Synoptic-scale eddies
; Temporal evolution
; Two-way interaction
; Vorticity transports
; Climate change
; Digital storage
; Energy conversion
; Space applications
; Vorticity
; Tropical engineering
; barotropic motion
; climate forcing
; climate oscillation
; computer simulation
; eddy
; seasonal variation
; summer
; vorticity
; Pacific Ocean
; Pacific Ocean (North)
英文摘要: The spatial structure and temporal evolution of the intraseasonal oscillation (ISO) in boreal summer over the midlatitudeNorth PacificOcean are investigated, through the diagnosis ofNCEP reanalysis data. It is found that the midlatitude ISO has an equivalent-barotropic structure, with maximum amplitude at 250 hPa. Initiated near 120°W, the ISOperturbation propagates westward at a phase speed of about 2.4 m s-1 and reaches a maximum amplitude at 1508W. A diagnosis of barotropic energy conversion shows that the ISO gains energy from the summer mean flow in the ISO activity region. A center-followed column-averaged vorticity budget analysis shows that the nonlinear eddy meridional vorticity transport plays a major role in the growth of the ISO perturbation. There is a two-way interaction between ISO flows and synoptic eddies. While a cyclonic (anticyclonic) ISOflow causes synoptic-scale eddies to tilt toward the northwest-southeast (northeast-southwest) direction, the tilted synoptic eddies then exert a positive feedback to reinforce the ISO cyclonic (anticyclonic) flow through eddy vorticity transport. The reanalysis data and numerical simulations show that the midlatitude ISO is primarily driven by local processes and the tropical forcing accounts for about 20%of total intraseasonal variability in midlatitudes.However, 20%might be an underestimate given that the tropical intraseasonal forcing is not fully included in the current observational analysis and modeling experiment. © 2013 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/52017
Appears in Collections: 气候变化事实与影响
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作者单位: National Key Lab. of Numerical Modeling for Atmospheric Sciences Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, and National Satellite Meteorological Center, Beijing, China; International Pacific Research Center, Department of Meteorology, University of Hawaii at Manoa, Honolulu, HI, United States; Chinese Academy of Meteorological Sciences, Beijing, China
Recommended Citation:
Wang L.,Li T.,Zhou T.,et al. Origin of the intraseasonal variability over the north pacific in boreal summer[J]. Journal of Climate,2013-01-01,26(4)