DOI: 10.1007/s00382-015-2618-x
Scopus记录号: 2-s2.0-84957428402
论文题名: Effects of tropical North Atlantic SST on tropical cyclone genesis in the western North Pacific
作者: Yu J. ; Li T. ; Tan Z. ; Zhu Z.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2016
卷: 46, 期: 2017-03-04 起始页码: 865
结束页码: 877
语种: 英语
英文关键词: Teleconnection
; Tropical cyclone genesis in the western North Pacific
; Tropical North Atlantic SST
英文摘要: The tropical cyclone genesis number (TCGN) in July–October (JASO) over the western North Pacific (WNP) exhibits a robust interannual variation. It shows a longitudinally tri-pole pattern with a high in the eastern WNP and South China Sea (SCS) and a low in the western WNP, which explain 42.2 and 23.4 % of total TCGN variance in the eastern WNP and SCS, respectively. The high–low–high pattern is similar to that derived from a TC genesis potential index (GPI). To understand the cause of the longitudinal distribution of the dominant interannual mode, we examine the contributions of environmental parameters associated with GPI. It is found that relative humidity and relative vorticity are important factors responsible for TC variability in the SCS, while vertical shear and relative vorticity are crucial in determining TC activity in eastern WNP. A simultaneous correlation analysis shows that the WNP TCGN in JASO is significantly negatively correlated (with a correlation coefficient of −0.5) with sea surface temperature anomalies (SSTA) in the tropical North Atlantic (TNA). The longitudinal distribution of TC genesis frequency regressed onto TNA SSTA resembles that regressed upon the WNP TCGN series. The spatial patterns of regressed environmental variables onto the SSTA over the TNA also resemble those onto TCGN in the WNP, that is, an increase of relative humidity in the SCS and a weakening of vertical shear in the eastern WNP are all associated with cold SSTA in the TNA. Further analyses show that the cold SSTA in the TNA induce a negative heating in situ. In response to this negative heating, a low (upper)-level anomalous aniti-cyclonic (cyclonic) flows appear over the subtropical North Atlantic and eastern North Pacific, and to east of the cold SSTA, anomalous low-level westerlies appear in the tropical Indian Ocean. Given pronounced mean westerlies in northern Indian Ocean in boreal summer, the anomalous westerly flows increase local surface wind speed and surface evaporation and cool the SST in situ. Cold SSTA in northern Indian Ocean further suppress local convection, inducing anomalous westerlies to its east, leading to enhanced cyclonic vorticity and low surface pressure over the WNP monsoon trough region. Idealized numerical experiments further confirm this Indian Ocean relaying effect, through which cold SSTA in the tropical Atlantic exert a remote impact to circulation in the WNP. © 2015, Springer-Verlag Berlin Heidelberg. 资助项目: IPRC, National Natural Science Foundation of China
; NSFC, National Natural Science Foundation of China
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/53827
Appears in Collections: 过去全球变化的重建
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作者单位: CDRC/ESMC, International Laboratory on Climate and Environment Change, Nanjing University of Information Science and Technology, Nanjing, China; IPRC and Department of Atmospheric Sciences, University of Hawaii, Honolulu, HI, United States; Key Laboratory of Mesoscale Severe Weather/Ministry of Education, Nanjing University, Nanjing, China
Recommended Citation:
Yu J.,Li T.,Tan Z.,et al. Effects of tropical North Atlantic SST on tropical cyclone genesis in the western North Pacific[J]. Climate Dynamics,2016-01-01,46(2017-03-04)