DOI: 10.1002/2016JD025893
论文题名: Potential vorticity regimes over East Asia during winter
作者: Huang W. ; Chen R. ; Wang B. ; Wright J.S. ; Yang Z. ; Ma W.
刊名: Journal of Geophysical Research: Atmospheres
ISSN: 2169897X
出版年: 2017
卷: 122, 期: 3 起始页码: 1524
结束页码: 1544
语种: 英语
英文关键词: blocking circulation
; East Asian winter monsoon
; potential vorticity regimes
; regime transitions
; severe cold spells
Scopus关键词: atmospheric circulation
; monsoon
; phase transition
; potential vorticity
; spatiotemporal analysis
; stratosphere-troposphere interaction
; surface temperature
; temperature anomaly
; warming
; winter
; Far East
英文摘要: Nine potential vorticity (PV) regimes over East Asia are identified by applying a Self-Organizing Map and Hierarchical Ascendant Classification regime analysis to the daily PV reanalysis fields on the 300 K isentropic surface for December–March 1948–2014. According to the surface temperature anomalies over East Asia, these nine regimes are further classified into three classes, i.e., cold class (three regimes), warm class (four regimes), and neutral class (two regimes). The PV-based East Asian winter monsoon index (EAWMI) is used to study the relationship between PV distributions and the temperature anomalies. The magnitude of cold (warm) anomalies over the land areas of East Asia increases (decreases) quasi-linearly with the EAWMI. Regression analysis reveals that cold temperature anomalies preferentially occur when the EAWMI exceeds a threshold at ∼0.2 PVU (where 1 PVU ≡ 10−6 m2 K kg−1 s−1). PV inversion uncovers the mechanisms behind the relationships between the PV regimes and surface temperature anomalies and reveals that cold (warm) PV regimes are associated with significant warming (cooling) in the upper troposphere and lower stratosphere. On average, cold regimes have longer durations than warm regimes. Interclass transition probabilities are much higher for paths from warm/neutral regimes to cold regimes than for paths from cold regimes to warm/neutral regimes. Besides, intraclass transitions are rare within the warm or neutral regimes. The PV regime analysis provides insight into the causes of severe cold spells over East Asia, with blocking circulation patterns identified as the primary factor in initiating and maintaining these cold spells. ©2017. American Geophysical Union. All Rights Reserved. 资助项目: 41505063
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/62698
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: Ministry of Education Key Laboratory for Earth System Modeling, and Department of Earth System Science (DESS), Tsinghua University, Beijing, China; State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences, Beijing, China
Recommended Citation:
Huang W.,Chen R.,Wang B.,et al. Potential vorticity regimes over East Asia during winter[J]. Journal of Geophysical Research: Atmospheres,2017-01-01,122(3)