DOI: 10.1002/jgrd.50385
论文题名: Linear interference and the Northern Annular Mode response to tropical SST forcing: Sensitivity to model configuration
作者: Fletcher C.G. ; Kushner P.J.
刊名: Journal of Geophysical Research Atmospheres
ISSN: 21698996
出版年: 2013
卷: 118, 期: 10 起始页码: 4267
结束页码: 4279
语种: 英语
英文关键词: el nino
; northern annular mode
; planetary wave
; teleconnections
; tropical sea surface temperature
; winter
Scopus关键词: Atmospheric pressure
; Atmospheric temperature
; Climate change
; EL Nino
; Northern annular mode
; Planetary Waves
; Sea surface temperature (SST)
; Teleconnections
; winter
; Tropics
; amplitude
; El Nino-Southern Oscillation
; general circulation model
; nonlinearity
; planetary wave
; sea surface temperature
; standing wave
; stratosphere
; wave field
; winter
英文摘要: Interannual variability in tropical sea surface temperatures (SSTs) associated with the El Niño-Southern Oscillation is linked to teleconnections with the Northern Annular Mode (NAM). Previous work highlighted that the sign and amplitude of the NAM response to tropical SSTs are controlled by the total wave activity entering the subpolar stratosphere, which depends on the linear interference of planetary wave anomalies with the climatological stationary wave field. This study uses multiple configurations of atmospheric general circulation models to assess the robustness of these linkages to details of the tropical SST forcing and model configuration. Across 23 cases with idealized SST forcing, the amplitudes of the tropical and extratropical wave responses are found to scale approximately linearly with forcing strength. But wave amplitude alone is not sufficient to predict the NAM response. Instead, the spatial structure of the wave response (and hence the linear interference) provides the best explanation of the NAM response in all cases. Linear interference explains most of the total wave activity response even in cases with stronger nonlinear contributions, due to consistent cancellation between quasi-stationary wave nonlinearity and nonlinearity arising from transient waves. Within this limited set of experiments, there is no evidence for a consistent sensitivity of the NAM response to horizontal resolution or to vertical resolution in the stratosphere. These findings reveal that linear interference provides a robust and reproducible mechanism linking midlatitude wave responses to zonal mean circulation (NAM) responses across a wide variety of forcing cases. Key Points Linear interference explains NAM response to tropical forcingLinear interference can dominate due to cancellation of nonlinear termsNo evidence for sensitivity of NAM response to model configuration ©2013. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/63758
Appears in Collections: 影响、适应和脆弱性 气候减缓与适应
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作者单位: Department of Geography and Environmental Management, University of Waterloo, 200 University Ave. W., Waterloo, ON N2L 3G1, Canada; Department of Physics, University of Toronto, Toronto ON, Canada
Recommended Citation:
Fletcher C.G.,Kushner P.J.. Linear interference and the Northern Annular Mode response to tropical SST forcing: Sensitivity to model configuration[J]. Journal of Geophysical Research Atmospheres,2013-01-01,118(10)