DOI: 10.1175/JCLI-D-17-0155.1
Scopus记录号: 2-s2.0-85040598284
论文题名: Why are temperature and upward wave activity flux positively skewed in the polar stratosphere?
作者: Watt-Meyer O. ; Kushner P.J.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2018
卷: 31, 期: 1 起始页码: 115
结束页码: 130
语种: 英语
英文关键词: Spectral analysis/models/distribution
; Stationary waves
; Stratosphere-troposphere coupling
; Stratospheric circulation
Scopus关键词: Atmospheric chemistry
; Higher order statistics
; Spectrum analysis
; Temperature distribution
; Troposphere
; Distribution of temperature
; Flux distributions
; Linear interference
; Nonlinear dependence
; Spectral analysis/models/distribution
; Stationary waves
; Stratosphere-troposphere coupling
; Stratospheric circulations
; Fluxes
; atmospheric circulation
; climatology
; ozone
; spectral analysis
; standing wave
; stratosphere-troposphere interaction
; temperature anomaly
; winter
英文摘要: The distribution of temperatures in the wintertime polar stratosphere is significantly positively skewed, which has important implications for the characteristics of ozone chemistry and stratosphere-troposphere coupling. The typical argument for why the temperature distribution is skewed is that radiative balance sets a firm lower limit, while planetary wave driving can force much larger positive anomalies in temperature. However, the distribution of the upward Eliassen-Palm (EP) flux is also positively skewed, and this suggests that dynamics may play an important role in setting the skewness of the temperature distribution. This study explains the skewness of the upward EP flux distribution by appealing to the ideas of linear interference. In this framework, fluxes are decomposed into a linear term (LIN) that measures the coherence of the wave anomaly and the climatological wave and an additional nonlinear term (NONLIN) that depends only on the wave anomaly. It is shown that when filtered by wavenumber, there is a clear nonlinear dependence between LIN and NONLIN: the terms cancel when LIN is negative, but they reinforce each other when LIN is positive. This leads to the positive skewness of the upward wave activity flux. A toy model of wave interference is constructed, and it is shown that the westward vertical tilt of the climatological wave is the key ingredient to a positively skewed upward EP flux distribution. The causes of the skews of the LIN and NONLIN distributions themselves are shown to be related to relationships between wave phase and amplitude, and wave phase and vertical tilt, respectively. © 2018 American Meteorological Society.
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/111702
Appears in Collections: 气候减缓与适应
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作者单位: Department of Atmospheric Sciences, University of Washington, Seattle, WA, United States; Department of Physics, University of Toronto, Toronto, ON, Canada
Recommended Citation:
Watt-Meyer O.,Kushner P.J.. Why are temperature and upward wave activity flux positively skewed in the polar stratosphere?[J]. Journal of Climate,2018-01-01,31(1)