DOI: 10.1175/JCLI-D-17-0327.1
Scopus记录号: 2-s2.0-85053037705
论文题名: Southern hemisphere origins for interannual variations of snow cover over the western Tibetan Plateau in boreal summer
作者: Dou J. ; Wu Z.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2018
卷: 31, 期: 19 起始页码: 7701
结束页码: 7718
语种: 英语
英文关键词: Annular mode
; Antarctic oscillation
; Atmosphere-ocean interaction
; Interannual variability
; Rossby waves
; Snow cover
Scopus关键词: Atmospheric temperature
; Atmospheric thermodynamics
; Climate change
; Mechanical waves
; Ocean currents
; Ray tracing
; Storms
; Surface waters
; Tropics
; Annular mode
; Antarctic oscillation
; Atmosphere-ocean interactions
; Interannual variability
; Rossby wave
; Snow covers
; Snow
英文摘要: The climate response to the Tibetan Plateau (TP) snow cover (TPSC) has been receiving extensive concern. However, relatively few studies have been devoted to revealing the potential factors that can contribute to the TPSC interannual variability, especially during boreal summer. This study finds that the May Southern Hemisphere (SH) annular mode (SAM), the dominating mode of atmospheric circulation variability in the SH extratropics, exhibits a significant positive relationship with the interannual variations in western TPSC during boreal summer. Observational analysis and numerical experiments manifest that the signal of the May SAM can be "prolonged" by a meridional Indian Ocean tripole (IOT) sea surface temperature anomaly (SSTA) via atmosphere-ocean interaction. The IOT SSTA pattern persists into the following summer and excites anomalous local-scale zonal-vertical circulation. Subsequently, a tropical dipole rainfall (TDR) mode is induced with precipitation anomalies between the tropical western Indian Ocean and the eastern Indian Ocean-Maritime Continent. Rossby wave ray tracing diagnosis reveals that the wave energies, generated by the latent heat release of the TDR mode, can propagate northward into the western TP. As a response, abnormal cyclone (or anticyclone) and upward (or downward) movement are triggered over the western TP, providing favorable dynamical conditions for more (or less) TPSC. Moreover, the strong May SAM is usually followed by a cold air temperature anomaly over the western TP in summer, which is unfavorable for snow-cover melting, and vice versa. In brief, the IOT SSTA plays an "ocean bridge" role and the TDR mode plays an "atmosphere bridge" role in the process of the May SAM impacting the following summer TPSC variability. The results may provide new insight into the cross-equatorial propagation of the SAM influence. © 2018 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/110643
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: Earth System Modeling Center, Nanjing University of Information Science and Technology, Nanjing, China; Institute of Atmospheric Sciences, Fudan University, Shanghai, China
Recommended Citation:
Dou J.,Wu Z.. Southern hemisphere origins for interannual variations of snow cover over the western Tibetan Plateau in boreal summer[J]. Journal of Climate,2018-01-01,31(19)