摘要
This study investigates the effect of the initial tropical cyclone(TC)vortex structure on the intensity change during the eyewall replacement cycle(ERC)of TCs based on two idealized simulations using the Weather Research and Forecasting(WRF)model.Results show that an initially smaller TC with weaker outer winds experienced a much more drastic intensity change during the ERC than an initially larger TC with stronger outer winds.It is found that an initially larger TC vortex with stronger outer winds favored the development of more active spiral rainbands outside the outer eyewall,which slowed down the contraction and intensification of the outer eyewall and thus prolonged the duration of the concentric eyewall and slow intensity evolution.In contrast,the initially smaller TC with weaker outer winds corresponded to higher inertial stability in the inner core and weaker inertial stability but stronger filamentation outside the outer eyewall.These led to stronger boundary layer inflow,stronger updraft and convection in the outer eyewall,and suppressed convective activity outside the outer eyewall.These resulted in the rapid weakening during the formation of the outer eyewall,followed by a rapid re-intensification of the TC during the ERC.Our study demonstrates that accurate initialization of the TC structure in numerical models is crucial for predicting changes in TC intensity during the ERC.Additionally,monitoring the activity of spiral rainbands outside the outer eyewall can help to improve short-term intensity forecasts for TCs experiencing ERCs.
作者
杨昕玮
王玉清
王慧
徐晶
占瑞芬
YANG Xin-wei;WANG Yu-qing;WANG Hui;XU Jing;ZHAN Rui-fen(State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,China Meteorological Administration,Beijing 100081 China;University of Chinese Academy of Sciences,Beijing 101408 China;Department of Atmospheric Sciences and International Pacific Research Center,School of Earth and Ocean Science and Technology,University of Hawaii at Manoa,Honolulu,HI 96822 USA;Qingdao Joint Institute of Marine Meteorology,Chinese Academy of Meteorological Sciences,China Meteorological Administration,Qingdao,Shandong 266034 China;Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences,Hehai University,Shanghai 200438 China)
基金
National Key R&D Program of China (2022YFC3004200)
National Natural Science Foundation of China (42305007,41730960,41875057)
National Science Foundation (AGS-1834300)。
