DOI: 10.1002/2014GL061476
论文题名: Influence of the basic state zonal flow on convectively coupled equatorial waves
作者: Dias J. ; Kiladis G.N.
刊名: Geophysical Research Letters
ISSN: 0094-9715
EISSN: 1944-9446
出版年: 2014
卷: 41, 期: 19 起始页码: 6904
结束页码: 6913
语种: 英语
英文关键词: basic state
; equatorial dynamics
; rainfall
; tropical waves
Scopus关键词: Rain
; Basic state
; Dispersion properties
; Doppler shifting
; Equatorial waves
; Equivalent depth
; Observational data
; Shallow water theory
; Speed of propagation
; Shear flow
; barotropic motion
; convective system
; Doppler effect
; flow pattern
; troposphere
; wave modeling
; zonal flow
英文摘要: Observational data are used to test the hypothesis that the basic state modulates the dispersion properties of convectively coupled equatorial waves (CCEWs). This hypothesis is based on shallow water theory, which predicts that the zonal speed of propagation of such tropospheric equatorial modes is altered by the equivalent depth and the basic zonal flow. Localized space-time spectra are calculated to investigate how CCEW spectral peaks vary across the tropics and how they are affected by the variations in zonal wind observed geographically and by season. Doppler shifting by the basic state barotropic zonal flow is readily identified. Once this Doppler shifting is taken into account, the equivalent depths of CCEWs inferred from global power spectra are surprisingly uniform, both geographically and temporally. However, there are also detectable modulations that appear consistent with changes in vertical shear of the zonal flow, along with other shifts that are not as easily explained. Key Points CCEW phase speeds tend to shift as one would expect based on Doppler effectsObserved CCEW amplitudes vary strongly by season and basinObserved CCEWs equivalent depths are similar across seasons and basins ©2014. American Geophysical Union. All Rights Reserved. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84911397380&doi=10.1002%2f2014GL061476&partnerID=40&md5=0deeaeb8e4f00751edb2a2583fae2183
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/6979
Appears in Collections: 气候减缓与适应
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作者单位: Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, United States
Recommended Citation:
Dias J.,Kiladis G.N.. Influence of the basic state zonal flow on convectively coupled equatorial waves[J]. Geophysical Research Letters,2014-01-01,41(19).