Scopus记录号: 2-s2.0-85044924122
论文题名: Relationship between the onset date of the Meiyu and the South Asian anticyclone in April and the related mechanisms
作者: Li H. ; He S. ; Fan K. ; Wang H.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2019
卷: 52, 期: 2019-01-02 起始页码: 209
结束页码: 226
语种: 英语
英文关键词: Meiyu onset date
; Pacific-Japan like pattern
; Philippines Sea
; South Asian anticyclone
英文摘要: The onset date of the Meiyu has attracted extensive attention because it marks the beginning of the rainfall season in the Yangtze-Huai River basin (YHRB). In this study, the relationship between the onset dates of the Meiyu and its precursors is investigated; and the South Asian anticyclone (SAA) in April, which is generated by atmospheric apparent sources over South Asia, is introduced. The results show that years with stronger SAA in April are concurrent with earlier onsets of the Meiyu and increased precipitation in June over the YHRB and vice versa. The mechanisms involved in this relationship are further investigated. The SAA emerges in early April, and moves eastward to the western North Pacific (WNP) in the late pentad of April due to the abrupt zonal energy transport, leading to anomalous divergence in the upper troposphere over the WNP. The divergence anomaly enhances ascending motion in situ due to Ekman pumping, leading to an anomalous cyclone at lower levels over this region. Due to the southward-moving ascending motion and the presence of the lower tropospheric cyclone in the fourth pentad of May, the precipitation moves southward to the Philippine Sea (PHS). The associated stronger convection over the PHS further triggers a meridional overturning pattern, which develops into the Pacific-Japan like pattern (PJ-like pattern). The PJ-like pattern persists from the end of May to the beginning of June, which promotes the earlier onset of the Meiyu. In addition, due to the increased heating associated with the abundant precipitation over the PHS around the fourth pentad of May, the Western Pacific subtropical high (WPSH) shifts northward earlier. Ultimately, the earlier establishment of the PJ-like pattern and the earlier northward shift of the WPSH cause stronger-than-normal southwesterly flows and additional water vapor transport to the YHRB, leading to the advanced onset of the Meiyu and additional precipitation in June. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature. 资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/122441
Appears in Collections: 气候变化事实与影响
There are no files associated with this item.
作者单位: Nansen-Zhu International Research Centre, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China; Climate Change Research Center, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China; Geophysical Institute, University of Bergen, Bjerknes Centre for Climate Research, Bergen, 5007, Norway; Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Key Laboratory of Meteorological Disaster, Ministry of Education, Nanjing University of Information Science and Technology, Nanjing, China
Recommended Citation:
Li H.,He S.,Fan K.,et al. Relationship between the onset date of the Meiyu and the South Asian anticyclone in April and the related mechanisms[J]. Climate Dynamics,2019-01-01,52(2019-01-02)