摘要
0205号台风“威马逊”于7月初沿海北上影响浙江舟山。影响浙江舟山时台风中心气压仍有940hPa,在历史同期是少见的。本文初步分析认为,台风在北上过程中强度保持不变的原因是由于台风本身结构规则、尺度大,强而大的台风环流提供了广泛的辐合流入。台风外围深厚的暖湿水汽输送带为台风强度的维持提供了水汽和能量。台风强度维持与低层辐合高层辐散有关,高层辐散同时加剧了低层辐合。涡度场的对称分布,使水汽和能量向台风中心旋转,旋转风动能得以维持。弱的垂直切变和暖洋面的存在也是台风强度维持的原因之一。
Typhoon 'Ramasun' effected Zhoushan in the early July, 2002When it went northward, it remained strong intensity. By analyzing typhoon structure itself and other surrounding situation, we found that typhoon regularly structure, large scale and strong typhoon circulation provided extensive convergence, necessary water vapor and energy by the warm and damp vapor transfer zone surrounding typhoon. Upper air divergence enhanced lower air convergence, symmetrical vorticity distribution made vapor and energy revolving to typhoon center. Weak vertical shear and warm sea surface are other reasons to remain the intensity of typhoon.
出处
《海洋预报》
北大核心
2003年第3期1-6,共6页
Marine Forecasts
关键词
台风
强度
结构
辐合辐散
暖洋面
“威马逊”
typhoon intensity
structure
convergence and divergence
warm sea surface