China’s coastal regions,characterized by dense populations and industrial agglomeration,face escalating threats from typhoon disasters.Understanding the evolution of socio-economic exposure to future typhoon landfall...China’s coastal regions,characterized by dense populations and industrial agglomeration,face escalating threats from typhoon disasters.Understanding the evolution of socio-economic exposure to future typhoon landfalls under global change is critical for effective disaster risk management.This study utilizes future typhoon track data simulated by the regional climate model version 4(RegCM4),combined with projected population and Gross Domestic Product(GDP)data for China’s coastal regions under three Shared Socioeconomic Pathways(SSPs:SSP1,sustainability;SSP2,middle of the road;SSP5,fossil-fueled development).We analyze typhoon impact zones for future periods(2030s,2050s,and 2090s)under Representative Concentration Pathways(RCPs:RCP2.6,RCP4.5,and RCP8.5,representing low,medium,and high greenhouse gas emission scenarios,respectively).Exposure levels for 2030,2050,and 2100 are calculated based on the annual average frequency of typhoon impacts during these periods,aiming to quantify the distribution characteristics of typhoon-affected population and GDP in China’s coastal regions.Key findings reveal two high-frequency typhoon im-pact zones:the Taiwan Strait region and the northern Qiongzhou Strait region.Furthermore,under RCP2.6,typhoon impacts may ex-tend to Liaoning,while RCP4.5 and RCP8.5 scenarios indicate potential impacts reaching further north to Heilongjiang.Under RCP4.5,Northeast China will experience the largest typhoon-affected area(43.800×10^(4) km^(2))by the 2030s.High population and GDP exposure concentrates in the Yangtze River Delta,the Pearl River Delta,and the Taiwan Strait coastal areas.Notably,Liaoning’s cumulative ex-posed population may exceed 0.100×10^(8) by 2030 and 2050 under RCP4.5 and RCP8.5 due to typhoon track migration.Given China’s location within the Western Pacific typhoon high-incidence region,the northward expansion of impacts will substantially escalate socio-economic exposure in mid-latitude regions previously at lower risk.These findings underscore the imperative for enhanced disaster pre-vention,mitigation strategies and targeted countermeasure research.展开更多
This study introduces a new ocean surface friction velocity scheme and a modified Thompson cloud microphysics parameterization scheme into the CMA-TYM model.The impact of these two parameterization schemes on the pred...This study introduces a new ocean surface friction velocity scheme and a modified Thompson cloud microphysics parameterization scheme into the CMA-TYM model.The impact of these two parameterization schemes on the prediction of the movement track and intensity of Typhoon Kompasu in 2021 is examined.Additionally,the possible reasons for their effects on tropical cyclone(TC)intensity prediction are analyzed.Statistical results show that both parameterization schemes improve the predictions of Typhoon Kompasu’s track and intensity.The influence on track prediction becomes evident after 60 h of model integration,while the significant positive impact on intensity prediction is observed after 66 h.Further analysis reveals that these two schemes affect the timing and magnitude of extreme TC intensity values by influencing the evolution of the TC’s warm-core structure.展开更多
This study presents a comprehensive analysis of 132 tornadic events in northeastern China from 2004 to 2023,utilizing radar and ERA5 reanalysis data to investigate the climatology,environmental drivers,and synoptic li...This study presents a comprehensive analysis of 132 tornadic events in northeastern China from 2004 to 2023,utilizing radar and ERA5 reanalysis data to investigate the climatology,environmental drivers,and synoptic linkages with Northeast China cold vortices(NCCVs)of tornadic storms under different convective modes.Results reveal that discrete storms account for 70%of events,with clustered cells(CC)being the most frequent mode,while significant tornadoes(EF2+)are primarily associated with isolated cells(IC)and broken lines(BL).The storm mode distribution in northeastern China resembles that of the central United States but with a higher proportion of CC and lower IC.In contrast,southern China exhibits a higher frequency of quasi-linear(QL)modes(>50%),similar to European patterns.Although no single parameter clearly differentiates between all tornado modes,distinct morphological characteristics emerge through specific parameter combinations:NL modes are characterized by high 0-1 km storm-relative helicity(SRH1)and humidity but low 0-6 km shear(SR6),whereas IC modes display contrasting features with low SRH1 and high CAPE.Notably,83%of tornadoes are associated with NCCVs,preferentially forming in southeastern/southwestern quadrants.Strong tornadoes favor southeastern quadrants,while NCCV intensity correlates with tornadic distance from vortex centers.Three characteristic synoptic configurations emerge:(T1)strong deep vortices with vertically aligned cold troughs,generating southeast-dominant tornado clusters characterized by a high proportion of BL and QL modes;(T2)weaker vortices featuring sub-synoptic troughs,with southern-distributed events dominated by a predominance of the CC mode;(T3)transverse-trough systems exhibiting CAPE-SRH decoupling and reduced tornadic activity.This study enhances our understanding of tornadoes in northeastern China,informing future research on formation mechanisms,prediction methods,and disaster prevention strategies.展开更多
This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shea...This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shear(VWS),using idealized numerical experiments.Results reveal that the SE develops greater radial extent when surface winds align with VWS compared to counter-aligned conditions.In alignment configurations,shear-enhanced surface winds on the right flank amplify surface enthalpy fluxes,thereby elevating boundary-layer entropy within the downshear outer-core region.Subsequently,more vigorous outer rainbands develop,inducing marked acceleration of tangential winds in the outer core preceding SE formation.The resultant radial expansion of supergradient winds near the boundary-layer top triggers widespread convective activity immediately beyond the inner core.Progressive axisymmetrization of this convective forcing ultimately generates an expansive SE structure.展开更多
基金Under the auspices of National Key Research and Development Program of China(No.2017YFA0604902,2024YFF1306802)Natural Science Foundation of Fujian Province(No.2022J01497)Open Project of the Strait Meteorology Laboratory(No.2025KF03)。
文摘China’s coastal regions,characterized by dense populations and industrial agglomeration,face escalating threats from typhoon disasters.Understanding the evolution of socio-economic exposure to future typhoon landfalls under global change is critical for effective disaster risk management.This study utilizes future typhoon track data simulated by the regional climate model version 4(RegCM4),combined with projected population and Gross Domestic Product(GDP)data for China’s coastal regions under three Shared Socioeconomic Pathways(SSPs:SSP1,sustainability;SSP2,middle of the road;SSP5,fossil-fueled development).We analyze typhoon impact zones for future periods(2030s,2050s,and 2090s)under Representative Concentration Pathways(RCPs:RCP2.6,RCP4.5,and RCP8.5,representing low,medium,and high greenhouse gas emission scenarios,respectively).Exposure levels for 2030,2050,and 2100 are calculated based on the annual average frequency of typhoon impacts during these periods,aiming to quantify the distribution characteristics of typhoon-affected population and GDP in China’s coastal regions.Key findings reveal two high-frequency typhoon im-pact zones:the Taiwan Strait region and the northern Qiongzhou Strait region.Furthermore,under RCP2.6,typhoon impacts may ex-tend to Liaoning,while RCP4.5 and RCP8.5 scenarios indicate potential impacts reaching further north to Heilongjiang.Under RCP4.5,Northeast China will experience the largest typhoon-affected area(43.800×10^(4) km^(2))by the 2030s.High population and GDP exposure concentrates in the Yangtze River Delta,the Pearl River Delta,and the Taiwan Strait coastal areas.Notably,Liaoning’s cumulative ex-posed population may exceed 0.100×10^(8) by 2030 and 2050 under RCP4.5 and RCP8.5 due to typhoon track migration.Given China’s location within the Western Pacific typhoon high-incidence region,the northward expansion of impacts will substantially escalate socio-economic exposure in mid-latitude regions previously at lower risk.These findings underscore the imperative for enhanced disaster pre-vention,mitigation strategies and targeted countermeasure research.
基金supported by the National Key R&D Program of China[grant number 2023YFC3008004]。
文摘This study introduces a new ocean surface friction velocity scheme and a modified Thompson cloud microphysics parameterization scheme into the CMA-TYM model.The impact of these two parameterization schemes on the prediction of the movement track and intensity of Typhoon Kompasu in 2021 is examined.Additionally,the possible reasons for their effects on tropical cyclone(TC)intensity prediction are analyzed.Statistical results show that both parameterization schemes improve the predictions of Typhoon Kompasu’s track and intensity.The influence on track prediction becomes evident after 60 h of model integration,while the significant positive impact on intensity prediction is observed after 66 h.Further analysis reveals that these two schemes affect the timing and magnitude of extreme TC intensity values by influencing the evolution of the TC’s warm-core structure.
基金supported by the National Natural Science Foundation of China(Grant No.42305013)Joint Research Project for Meteorological Capacity Improvement(Grant Nos.23NLTSQ002 and 24NLTSQ001)+2 种基金China Meteorological Administration Tornado Key Laboratory(Grant No.TKL202307)the China Meteorological Administration Youth Innovation Team Fund(Grant No.CMA2024QN05)a research project of the Chinese Academy of Meteorological Science(Grant No.2023Z019)。
文摘This study presents a comprehensive analysis of 132 tornadic events in northeastern China from 2004 to 2023,utilizing radar and ERA5 reanalysis data to investigate the climatology,environmental drivers,and synoptic linkages with Northeast China cold vortices(NCCVs)of tornadic storms under different convective modes.Results reveal that discrete storms account for 70%of events,with clustered cells(CC)being the most frequent mode,while significant tornadoes(EF2+)are primarily associated with isolated cells(IC)and broken lines(BL).The storm mode distribution in northeastern China resembles that of the central United States but with a higher proportion of CC and lower IC.In contrast,southern China exhibits a higher frequency of quasi-linear(QL)modes(>50%),similar to European patterns.Although no single parameter clearly differentiates between all tornado modes,distinct morphological characteristics emerge through specific parameter combinations:NL modes are characterized by high 0-1 km storm-relative helicity(SRH1)and humidity but low 0-6 km shear(SR6),whereas IC modes display contrasting features with low SRH1 and high CAPE.Notably,83%of tornadoes are associated with NCCVs,preferentially forming in southeastern/southwestern quadrants.Strong tornadoes favor southeastern quadrants,while NCCV intensity correlates with tornadic distance from vortex centers.Three characteristic synoptic configurations emerge:(T1)strong deep vortices with vertically aligned cold troughs,generating southeast-dominant tornado clusters characterized by a high proportion of BL and QL modes;(T2)weaker vortices featuring sub-synoptic troughs,with southern-distributed events dominated by a predominance of the CC mode;(T3)transverse-trough systems exhibiting CAPE-SRH decoupling and reduced tornadic activity.This study enhances our understanding of tornadoes in northeastern China,informing future research on formation mechanisms,prediction methods,and disaster prevention strategies.
基金jointly supported by the National Natural Science Foundation of China[grant numbers U2342202,42175005,and 42175016]the Qing Lan Project[grant number R2023Q06]。
文摘This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shear(VWS),using idealized numerical experiments.Results reveal that the SE develops greater radial extent when surface winds align with VWS compared to counter-aligned conditions.In alignment configurations,shear-enhanced surface winds on the right flank amplify surface enthalpy fluxes,thereby elevating boundary-layer entropy within the downshear outer-core region.Subsequently,more vigorous outer rainbands develop,inducing marked acceleration of tangential winds in the outer core preceding SE formation.The resultant radial expansion of supergradient winds near the boundary-layer top triggers widespread convective activity immediately beyond the inner core.Progressive axisymmetrization of this convective forcing ultimately generates an expansive SE structure.
