DOI: 10.1175/JCLI-D-12-00202.1
Scopus记录号: 2-s2.0-84875042483
论文题名: Statistical characterization of Arctic polar-night jet oscillation events
作者: Hitchcock P. ; Shepherd T.G. ; Manney G.L.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2013
卷: 26, 期: 6 起始页码: 2096
结束页码: 2116
语种: 英语
Scopus关键词: Microwave limb sounder
; Middle atmosphere model
; Research and application
; Retrospective analysis
; Statistical characterization
; Stratospheric polar vortex
; Stratospheric sudden warmings
; Temperature observations
; Data processing
; Troposphere
; Vortex flow
; Upper atmosphere
; forecasting method
; polar vortex
; statistical analysis
; stratosphere
; temperature anomaly
; weather forecasting
英文摘要: A novel diagnostic tool is presented, based on polar-cap temperature anomalies, for visualizing daily variability of the Arctic stratospheric polar vortex over multiple decades. This visualization illustrates the ubiquity of extended-time-scale recoveries from stratospheric sudden warmings, termed here polar-night jet oscillation (PJO) events. These are characterized by an anomalously warm polar lower stratosphere that persists for several months. Following the initial warming, a cold anomaly forms in the middle stratosphere, as does an anomalously high stratopause, both of which descend while the lower-stratospheric anomaly persists. These events are characterized in four datasets: Microwave Limb Sounder (MLS) temperature observations; the 40-yr ECMWF Re-Analysis (ERA-40) and Modern Era Retrospective Analysis for Research and Applications (MERRA) reanalyses; and an ensemble of three 150-yr simulations from the Canadian Middle Atmosphere Model. The statistics of PJO events in the model are found to agree very closely with those of the observations and reanalyses. The time scale for the recovery of the polar vortex following sudden warmings correlates strongly with the depth to which the warming initially descends. PJO events occur following roughly half of all major sudden warmings and are associated with an extended period of suppressed wave-activity fluxes entering the polar vortex. They follow vortex splits more frequently than they do vortex displacements. They are also related to weak vortex events as identified by the northern annular mode; in particular, those weak vortex events followed by a PJO event show a stronger tropospheric response. The long time scales, predominantly radiative dynamics, and tropospheric influence of PJO events suggest that they represent an important source of conditional skill in seasonal forecasting. © 2013 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/51949
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Physics, University of Toronto, Toronto, ON, Canada; Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States; New Mexico Institute of Mining and Technology, Socorro ,NM, United States
Recommended Citation:
Hitchcock P.,Shepherd T.G.,Manney G.L.. Statistical characterization of Arctic polar-night jet oscillation events[J]. Journal of Climate,2013-01-01,26(6)