近海北上热带气旋特征及对华东沿海地区影响分析  

ANALYSES OF FEATURES OF COASTAL NORTHBOUND TROPICAL CYCLONES AND THE IMPACT ON COASTAL EAST CHINA

作　　者：曹晓岗[1] 王慧[1] 傅洁[1] 张吉[1] 施春红[1] 

机构地区：[1]上海中心气象台,上海200030

出　　处：《热带气象学报》2014年第5期861-870,共10页Journal of Tropical Meteorology

基　　金：中国气象局预报员专项"台风移向与环境场平均风关系的统计分析"(CMAYBY2012-019);"近海北上热带气旋对华东沿海地区影响分析"(CMAYBY2013-022)共同资助

摘　　要：使用常规观测、FY2C卫星云图、CIMSS气象卫星云图分析、2000—2012年台风路径、NCEP再分析等资料,统计了2000年以来近海北上的热带气旋(下面统称为NTC)对华东沿海地区的风雨影响,分析了NTC的路径、强度、结构等特征,以及与华东沿海地区的风雨的关系。结果表明NTC对华东沿海地区是否有较严重风雨影响,取决于其北上路径与沿海地区距离的远近、NTC的强度和范围大小。当NTC中心距离陆地<300 km,在124.5°E以西北上对华东沿海地区有较严重风雨影响,如果NTC强度在台风等级以上时会对上海产生较严重风雨影响。在125°E以东北上的NTC,强度在台风等级以下时对华东沿海地区影响较小。NTC在东海近海北上时,强台风、超强台风的强度是逐渐减弱的;较弱的台风或强热带风暴及热带风暴强度将维持或略有加强。NTC在东海近海北上时,当离沿海地区距离<300 km时,结构易变得非对称。强度强和范围大的NTC结构也易变得非对称。NTC结构变得非对称后其强度将进一步减弱。随着NTC北上海温逐渐降低,在NTC西部靠近陆地其水汽条件比东部差,NTC结构会变得不对称,NTC北上到较高纬度风的垂直切变一般会变大,NTC脱离赤道辐合带后其水汽输送条件变差等等都会使较强的NTC北上后减弱。另外,NTC与所处的高低空环境相互作用也会影响其强度变化。Using various data,including routine observations,FY2C satellite images,CIMSS meteorological satellite cloud images,CMA-STI Best Track Dataset for typhoon,and NCEP reanalysis data,analyses are performed on the features （path,intensity and structure） of the coastal northbound tropical cyclones （NTC for short） since 2000,the wind and rain impacts caused by a NTC on East China,and the relationship between the features and impacts.The results are shown as follows.（1） The impacts depend on NTC＇s size and strength,and the distance between the NTC and the area expected to be affected.Heavy rain and strong wind can be brought in when a NTC moves north in areas west of 124.5 °E and is within a 300 km radius from the coast of East China.Serious damage might be caused if the NTC is above the intensity of typhoon.However,the effects would be limited if a NTC is below the intensity of typhoon and follows a northward path east of 125 ° E.（2） An NTC that equals to or exceeds typhoon in intensity usually weakens on its way to the north in the East China Sea.On the contrary,a less strong NTC maintains or slightly increases during the same process.（3）An NTC becomes asymmetrically structured easily when it is within a radius of 300 km from the coast,especially when it is strong in intensity or extensive in horizontal scale.afterwards,the NTC further weakens.（4） Variable factors account for strong NTC＇s weakening：cooled underlying sea surface decreases part ofNTC＇s energy,there is less water vapor in the western NTC than the eastern contributing to asymmetric structure,there is large vertical wind shear in high latitudes,and less water vapor is supplied because of distant sources.In addition,the interaction of NTC with environmental circulation will also change its intensity.

关 键 词：天气学 热带气旋统计 路径 强度 结构特征 风雨影响 

分 类 号：P444[天文地球—大气科学及气象学]