“苏拉”台前强螺旋云带辐合特征分析  

Convergence Characteristics of Severe Prefrontal Spiral Cloud Band of Typhoon Saola

作　　者：徐亚钦 夏园锋 翟国庆[2] 黄艳 XU Yaqin;XIA Yuanfeng;ZHAI Guoqing;HUANG Yan(Jinhua Meteorological Office of Zhejiang Province,Jinhua 321099;Department of Earth Sciences,Zhejiang University,Hangzhou 310027)

机构地区：[1]浙江省金华市气象局,金华321099 [2]浙江大学地球科学系,杭州310027

出　　处：《气象》2018年第10期1275-1285,共11页Meteorological Monthly

基　　金：国家自然科学基金项目(41575042);金华市科学技术局社会发展类一般项目(20153029)共同资助

摘　　要：为了研究爆发式发展的台风苏拉台前强螺旋云带,采用多种实况资料,运用风场分解、Shuman-Shapiro滤波、雷达回波相关性跟踪(TREC)反演风场等方法对其辐合特征进行分析。结果表明:从中尺度滤波场、变风场以及风场分解后的辐散风可见,螺旋云带形成于大范围辐合背景下。在低层,旋转风是水平动能输入的主要贡献者,它加强了低层动量堆积,辐散风则加强了风场水平辐合;在高层,辐散风是动能输出的主要贡献者,辐散风的增强,加强了高空辐散。旋转风和辐散风的不同配置形成了强上升运动,从而促进了强螺旋云带的发展。对地面风场进行中尺度滤波后,在选取的两个关键区内可见明显的中尺度辐合或涡旋,且辐合在更高层仍有一定的反映。中小尺度辐合与螺旋云带中对流云团的发展相互对应、相互反馈。This paper analyses the convergence Saola by using variety of observation data, wind characteristics of explosive spiral cloud band of Typhoon decomposing, Shuman-Shapiro filtering and TREC （Tra- cking Radar Echoes by Correlation） wind inversion methods. The results indicate that spiral cloud band formed in the background of large-scale convergence from the mesoscale filter wind, variation wind and di- vergent wind after decomposition. The low-level rotational wind was the major contributor to the horizon- tal kinetic energy input, which strengthened the low-layer momentum accumulation. Besides, the diver- gent wind strengthened the convergence. The upper divergent wind was the major contributor to kinetic energy output, which strengthened the upper divergence. The rotational and divergent wind strengthened the vertical motion, promoting the development of severe spiral cloud band. After surface mesoscale filte- ring, we could see obvious mesoscale convergence or vortex in the two areas, which were also reflected in higher levels. Thus, the mesoscale convergence zone and spiral cloud band affect each other.

关 键 词：螺旋云带 中尺度辐合 风场分解 中尺度滤波 

分 类 号：P458[天文地球—大气科学及气象学]