台风Khanun迅速加强成因及其与Rananim登陆强度的比较分析

以严重影响我国的2005年15号登陆台风Khanun为研究对象,首先从大尺度环流特征和物理量场,对其登陆前强度迅速加强原因进行了诊断分析,结果表明,台风强度增强与低空持续加强的水汽输送、高空流出气流的强辐散、台风移向垂直切变小值区和暖洋面密切相关;然后就登陆时强度,将Khanun与2004年14号台风Rananim从水平流场、暖心结构、稳定度和涡度等方面进行对比,发现Khanun在上述几方面略弱于Rananim,这一结论为登陆台风强度判定提供了一些参考。

Analysis on Causes of Quick Strengthening of Typhoon Khanun and Comparison of Landfall Intensity with Rananim

The study was carried out on the landfall typhoon 0515 Khanun which affected East China seriously. Firstly, based on the characteristics of large-scale circulation and physics factors, the causes of the quick strengthening, which came ahead of its landfall, were analyzed. The results show that the enhancement of intensity was associated with lower layer moisture transportation, upper level strong divergence, and the typhoon moving to where vertical shear was low and sea surface temperature was high. Secondly, focusing on horizontal stream field, the structure of warm core, the stability and vorticity, and the landfall intensity were comparative analyzed between typhoon Khanun and Rananim. It is found that Khanun was weaker than Rananim in these aspects; this conclusion may serve as references on judging the landfall intensity of typhoon.