热带气旋变性过程客观判别方法在“海马”变性过程中的应用

介绍了一种判别热带气旋变性过程的客观方法.此客观方法使用三个判别参数: 对流层低层热力非对称参数B、高低层的热成风、对变性过程进行诊断判别.此方法使用格点的数值预报产品,计算简单、使用方便,便于业务化.同时针对2004年影响我国的0421号热带风暴"海马",使用NCEP再分析资料对其变性过程进行了分析验证,结果表明:此客观方法所定义的三个判别参数B、、在"海马"的变性过程中有很好的指示作用.

APPLICATION OF AN OBJECTIVE DISCRIMINATING METHOD IN THE EVOLUTION OF TROPICAL CYCLONE "HAIMA" DURING EXTRATROPICAL TRANSITION

An objective discriminating method for the process of tropical cyclone extratropical transition (ET) was introduced. With this method, the grid output data of NWP were used to calculate three parameters: storm-relative thickness symmetry (B), low-level (-V_T^L) and upper-level thermal wind (-V_T^U). This objective method was easy to calculate and convenient for operational use. In this paper, using NCEP reanalysis data we verified this method to identify the evolution of extratropical transition for "Haima", a tropical storm that occurred in eastern China in 2004. The result showed that the three parameters were the indicators in the process of extratropical transition (ET).