长时间维持和迅速减弱的华南登陆热带气旋对比分析  

Comparison between long-time maintained tropical cyclone and rapidly weakened tropical cyclone landed in the South China

作　　者：黄滢[1,2] 彭俊龙 郭亮 

机构地区：[1]南京大学,大气科学,江苏南京210008 [2]广西省防城港市气象局,广西防城港538001

出　　处：《海洋预报》2013年第2期68-74,共7页Marine Forecasts

摘　　要：将登陆华南影响广西的热带气旋分为长时间维持(LTC)和维持时间短(STC)两类,并应用NCEP再分析资料,对这两类热带气旋的影响系统和物理量场进行对比分析,结果表明,两类热带气旋的影响系统和物理量场存在明显的差异。影响两类热带气旋的天气系统差异显著:影响LTC的200 hPa南亚高压强度一般在1252 hPa以上,而影响STC的南亚高压强度较弱;200 hPa高空槽距离LTC有一定的距离,高空槽前的辐散气流有利于热带气旋的维持,而STC距离高空槽很近,由于垂直切变增大,热带气旋将迅速减弱;副高和LTC的位置配置使得LTC东侧的急流将海上的水汽输送到热带气旋内部,有利于其维持,而当副高太强时,STC垂直环流会受到抑制,不利于其维持;LTC期间强的西南季风槽带来热带云团输送减缓了其环流的衰减,而影响STC西南季风较弱。物理量场方面,LTC高空辐散较STC明显偏强;登陆后LTC的两个水汽通道的水汽输送较STC均明显偏强;另外,Q矢量分析表明,Q矢量辐合辐散中心的强度变化在一定程度上反映出热带气旋衰减的过程。The tropical cyclones （TC） which landed in the South China were divided into two categories, long time maintained tropical cyclones （LTC） and that maintained short time （STC）. The NCEP reanalysis data were used to comparative analyze the synoptic situation and the physical field of the two types of TC. The results showed that the two types of TC had significant differences in synoptic situation and physical field. The strength of South Asia High that affected LTC was strong, generally larger than 1252hPa, while it was weak to STC. The trough had some distance away from the LTC centers. Because of the increase of vertical shear, the trough that was very close to the STC was unfavorable for maintenance. Due to the location of LTC and the subtropical high, the jet which formed in the east of LTC was in favor of the maintenance. When the subtropical high was too strong, the vertical circulation of STC would be suppressed and the maintenance of STC was not conducive. The strength of the southwest monsoon which affected LTC was stronger than that influenced STC. The upper-level divergence of LTC was significantly stronger than that of STC. The water vapor transports of two channels were sufficient during LTC. In addition, the Q-vector analysis showed that the centers of convergence and divergence certain extent reflect the process of tropical cyclone attenuation.

关 键 词：热带气旋 强度衰减 对比分析 合成分析 

分 类 号：P444[天文地球—大气科学及气象学]