Scopus记录号: 2-s2.0-85062686286
论文题名: Subseasonal zonal variability of the western Pacific subtropical high in summer: climate impacts and underlying mechanisms
作者: Guan W.N. ; Hu H.B. ; Ren X.J. ; Yang X.-Q.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2019
语种: 英语
英文关键词: Local air–sea interaction
; Rossby wave train
; Subseasonal variability
; Summer Yangtze rainfall
; The western Pacific subtropical high
英文摘要: The zonal oscillation of the western Pacific subtropical high (WPSH) significantly influences the weather and climate over East Asia. This study investigates characteristics and mechanisms of the zonal variability of the WPSH on subseasonal time scales during summer by using a subseasonal WPSH (Sub-WPSH) index. Accompanied with the Sub-WPSH index, strong anticyclonic (cyclonic) anomalies are found over East Asia and coastal region south of 30°N on both 850 hPa and 500 hPa. During the positive period of the Sub-WPSH index, the WPSH extends more westward with enhanced precipitation over the Yangtze–Huaihe river basin and suppressed precipitation over the south of the Yangtze River in China. These precipitation anomalies can last for at least 1 week. While the subseasonal zonal variability of the WPSH is found to be closely associated with atmospheric teleconnections and local air- sea interaction, the mechanisms of the variability are different before and after mid-July (early and late summer). In both early and late summer, the East Asia/Pacific (EAP) wave train pattern affects the zonal shift of the WPSH by inducing a low-level anomalous anticyclonic/cyclonic circulation over the subtropical western Pacific, and this mechanism is stronger in late summer. In constrast, the influence of the Silk-Road pattern wave train is more important in the early summer. Meanwhile, in late summer, a stronger SST forcing on the atmosphere and a faster cycle of subseasonal variations of the WPSH are observed before the westward stretch of the WPSH, which could be related to the colder local SST anomalies. The westward stretch of the WPSH is accompanied by stronger anticyclonic anomalies in late summer. © 2019, The Author(s). 资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/122510
Appears in Collections: 气候变化事实与影响
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作者单位: CMA-NJU Joint Laboratory for Climate Prediction Studies, Instituted for Climate and Global Change Research, School of Atmospheric Science, Nanjing University, Nanjing, 210093, China; Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing University of Information Science and Technology, Nanjing, 210044, China
Recommended Citation:
Guan W.N.,Hu H.B.,Ren X.J.,et al. Subseasonal zonal variability of the western Pacific subtropical high in summer: climate impacts and underlying mechanisms[J]. Climate Dynamics,2019-01-01