Based on the Regional Spectral Model(RSM) re-analysis data from Japan Meteorological Agency(JMA) with a horizontal resolution of 20 km and a time interval of 6 h,this study works on the outer and inner core size of 21...Based on the Regional Spectral Model(RSM) re-analysis data from Japan Meteorological Agency(JMA) with a horizontal resolution of 20 km and a time interval of 6 h,this study works on the outer and inner core size of 2174 samples of tropical cyclones(TCs) occurring over the western North Pacific between 2001 and 2007.Some conclusions have been drawn on the basis of preliminary analysis of the TC inner core size and outer size and their relationship with TC intensity.First,the outer size increase(decrease) helps TCs intensify(weaken).Second,the enlargement(shrinking) of the inner core size helps TCs intensify(weaken) if TCs have a large inner core(with radius of maximum winds larger than 120 km).Contrarily,when TCs have small inner core(with radius of maximum winds smaller than 120 km),the enlargement(shrinking) of the inner core is good for weakening(intensifying) of TCs.展开更多
Intensity variation of tropical cyclones(TCs),especially that of coastal or landfalling TCs,is of great concern in current research.Most of the research papers,however,focus on intensification processes of TCs;only a ...Intensity variation of tropical cyclones(TCs),especially that of coastal or landfalling TCs,is of great concern in current research.Most of the research papers,however,focus on intensification processes of TCs;only a few discuss decay processes in the lifetime of a TC.In the daily weather operation related to TCs,it is challenging when a TC weakens and/or disappears suddenly,because it brings more difficulties than the forecast of intensifying TCs does.Overestimation of a decaying landfalling TC would lead to over-preparation of defensive measures and result in"crying wolf"mentality with adverse effects.This study summarized physical mechanisms that dominate the decaying process of TCs and listed several possible dynamical factors:reduced level of air temperature,too large or too small speed,contraction of TC size amplification of TC's core,and lightning number in a TC.展开更多
基金Natural Fundamental Research and Development Project Program(2013CB430305)Specialized Research Project for Public Welfare Sector(Meteorology)(GYHY201406010)
文摘Based on the Regional Spectral Model(RSM) re-analysis data from Japan Meteorological Agency(JMA) with a horizontal resolution of 20 km and a time interval of 6 h,this study works on the outer and inner core size of 2174 samples of tropical cyclones(TCs) occurring over the western North Pacific between 2001 and 2007.Some conclusions have been drawn on the basis of preliminary analysis of the TC inner core size and outer size and their relationship with TC intensity.First,the outer size increase(decrease) helps TCs intensify(weaken).Second,the enlargement(shrinking) of the inner core size helps TCs intensify(weaken) if TCs have a large inner core(with radius of maximum winds larger than 120 km).Contrarily,when TCs have small inner core(with radius of maximum winds smaller than 120 km),the enlargement(shrinking) of the inner core is good for weakening(intensifying) of TCs.
基金Natural Fundamental Research and Development Project"973"Program(2009CB421504)Natural Science Foundation of China(40730948,40921160381,40905029)special scientific fund for non-profit public industry(GYHY201006008)
文摘Intensity variation of tropical cyclones(TCs),especially that of coastal or landfalling TCs,is of great concern in current research.Most of the research papers,however,focus on intensification processes of TCs;only a few discuss decay processes in the lifetime of a TC.In the daily weather operation related to TCs,it is challenging when a TC weakens and/or disappears suddenly,because it brings more difficulties than the forecast of intensifying TCs does.Overestimation of a decaying landfalling TC would lead to over-preparation of defensive measures and result in"crying wolf"mentality with adverse effects.This study summarized physical mechanisms that dominate the decaying process of TCs and listed several possible dynamical factors:reduced level of air temperature,too large or too small speed,contraction of TC size amplification of TC's core,and lightning number in a TC.
