台风“艾利”降水的非对称结构分析

ANALYSIS OF ASYMMETRICAL STRUCTURE OF PRECIPITATION IN TYPHOON AERES

利用NASA提供的热带测雨卫星TRMM(Tropical Rainfall Measuring Mission)的高分辨率资料分析了2004年台风"艾利"降水的结构特征,发现在不同发展阶段其特征存在着很大的不同。为了分析产生降水非对称的原因,又利用NCEP(the National Centers for Environmental Prediction)再分析资料计算了垂直积分的水汽通量矢量。结果表明,本次过程由于伴随着双台风特有的环流形势,其北侧的偏东气流和南侧的西南气流对水汽输送的作用,在台风"艾利"发展的不同时期存在很大的不同,形成了这次台风过程特有的水汽来源特点。台风对流强降水区、水汽通量最大区和强上升运动区三者的分布在台风不同发展阶段存在着较大的差异,正是水汽通量和垂直运动的非均匀分布才造成这次台风降水的非对称分布。

In this paper, high-resolution data of TRMM are used, which are provided by NASA, and the structural characteristics of precipitation of typhoon AERE（2004） is analyzed, which shows that its characteristics are very different at various phases. In order to analyze the asymmetrical causation of precipitation distribution, NCEP reanalysis data are used to calculate water vapor flux vector of the vertical integration. Results show that, in this process, there is a specific circulating current accompanying with twin typhoons, the easterly air current north of them and southwesterly air current south of them are transporting water vapor, its transport effects are very different at vary evolution stages of AERE, to contribute to the peculiarity of water source for this process of typhoon. The distribution of a strong convective precipitation area of the typhoon, maximum value area of the water vapor flux and strong ascending motion area differs at different development stages and it is the non-uniform distribution of water vapor flux and vertical motion that brings about unsymmetrical distribution of typhoon precipitation.