DOI: 10.1175/JCLI-D-12-00581.1
Scopus记录号: 2-s2.0-84880676926
论文题名: Influences of enso on stratospheric variability, and the descent of stratospheric perturbations into the lower troposphere
作者: Li Y. ; Lau N.-C.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2013
卷: 26, 期: 13 起始页码: 4725
结束页码: 4748
语种: 英语
Scopus关键词: Coupled climate model
; Eddy-mean flow interaction
; Near-surface winds
; North Atlantic oscillations
; Stratospheric polar vortex
; Stratospheric variability
; Stratospheric vortex
; Vertical resolution
; Atmospheric pressure
; Climate models
; Troposphere
; Upper atmosphere
; Vortex flow
; climate modeling
; climate variation
; El Nino-Southern Oscillation
; geopotential
; La Nina
; North Atlantic Oscillation
; planetary wave
; polar vortex
; stratosphere
; troposphere
; vortex flow
; wave propagation
英文摘要: The linkage between El Niño-Southern Oscillation (ENSO) and North Atlantic Oscillation (NAO) through the stratospheric pathway is examined using a global coupled climate model [GFDL Climate Model version 3 (CM3)], with increased vertical resolution and extent in the stratosphere as compared to an earlier model [GFDL Climate Model version 2 (CM2)]. It is demonstrated that the relationship between ENSO and NAO is stronger in CM3 than in CM2. It is found that ENSO plays an important role in modulating the frequency of occurrence of the stratospheric polar vortex anomalies through enhancement/attenuation of the amplitudes of zonal wavenumbers 1 and 2, especially in late winter. Ahigher frequency of weak (strong) stratospheric vortex events is simulated in CM3 during El Niño (La Niña) episodes. The weak vortex events during El Niño winters are preceded by enhancement of the zonal wave-1 pattern and weakening of zonal wave-2 pattern. These modified tropospheric planetary waves propagate upward and then weaken the stratospheric polar vortex through eddy-mean flow interaction. The zonal-mean geopotential response in the stratosphere propagates downward and weakens the polar vortex throughout the troposphere. The effects of planetary wave refraction in the upper troposphere on the zonally averaged circulation cells in the tropospheric meridional plane, and the linkage between the lower branches of these cells and the nearsurface wind patterns, play an important role in the flow pattern over the region corresponding to the southern lobe of the NAO. Specifically, a negative annular mode and NAO response is discernible in weak stratospheric vortex events during El Niño. Conversely, the positive annular mode and NAO is evident in strong vortex events during La Niña. © 2013 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/51767
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Atmospheric Science, Colorado State University, Fort Collins, CO, United States; NOAA, Geophysical Fluid Dynamics Laboratory, Princeton, NJ, United States
Recommended Citation:
Li Y.,Lau N.-C.. Influences of enso on stratospheric variability, and the descent of stratospheric perturbations into the lower troposphere[J]. Journal of Climate,2013-01-01,26(13)