台风“尤特”的等熵位涡分析  

Isentropic Potential Vorticity Analysis of Typhoon ' Utor'

作　　者：黎惠金 黄明策[2] 覃昌柳 

机构地区：[1]广西来宾市气象局,来宾546100 [2]广西区气象台,南宁530022

出　　处：《高原气象》2016年第3期777-787,共11页Plateau Meteorology

基　　金：中国气象局2014年预报员专项(CMAYBY2014-052)

摘　　要：利用等熵位涡理论对2013年严重影响华南的"尤特"台风过程进行了诊断分析,结果表明,"尤特"活动期间,其环流中心上空高层有随台风移动的高位涡大值中心下传,且高层位涡下传的强弱与下传区相对台风的位置与台风强度和移向变化关系密切,表现为台风一般沿着台风上空等熵位涡分布的长轴方向移动,高层位涡增加后,台风中心气压下降,强度加强。高层高位涡的下传,导致动力对流层顶下降,在高位涡异常区前方低层激发气旋性环流,形成低涡或气旋,从而影响台风移动,而低涡或气旋生成后对对流层高层位涡扰动又有正反馈作用,促使台风加强。由于高层高位涡下传对台风强度产生的正影响,及周边高位涡空气的输送、后期冷空气的南移和孟加拉湾、台湾以东洋面热带气旋的发展带来的东、西、北三支高位涡空气的注入,台风"尤特"生成后强度快速增强。The Isentropic Potential Vorticity（IPV） theory is used to Typhoon ＇Utor＇ which seriously impacted the southern China in 2013.The result showed that：during the activity of ＇Utor＇,the upper-level high Potential Vorticity（PV） over the top of the circulation center transported downward with typhoon movement,and the intensity and position of upper-level high PV transmission downward were close related to typhoon intensity and moving direction changed,the performance are typhoon movement generally along the long axis direction of the IPV distribution,PV increased in upper-level,the central pressure decreased,the intensify strengthen.The upper-level high PV transported downward,the dynamic tropopause descended and led to a cyclone circulation in front of the PV anomaly area,resulted in generating vortex or cyclone,and impactied typhoon movement.The cyclone circulation had a positive feedback on the upper-level PV,that was advantaged to typhoon.Because of the positive influence of the upper-level high PV transmission downward to typhoon intensity,and the high PV air around was transported,and the cold air moved southward in later period,the tropical cyclones generated at Bay of Bengal and the northwest Pacific,at the east of Taiwan,totally,three high PV streams transported into＇Utor＇ from east,west and north.As a result,＇Utor＇ strengthened quickly in the early stage,developed again when it moved into South China Sea,maintained for a long time after landing.

关 键 词：台风 等熵位涡 高位涡下传 机制 强度 移向 

分 类 号：P458.124[天文地球—大气科学及气象学]