一种分离暴雨过程天气尺度和次天气尺度特征的方法

作者提出利用奇异谱主分量重建技术进行气象变量场尺度分离的新构想,并设计出尺度分离的具体实施方法.使用此方法对1998年7月下旬长江流域强暴雨过程的卫星观测亮温(TBB)场进行了试验性尺度分离.结果表明,该分离技术可以将这次暴雨过程天气尺度和次天气尺度系统的基本结构清晰地分离出来.在天气尺度场上,长江流域呈现出明显的切变线上连续性对流云系的特征.在次天气尺度场上,可以清楚地显现出偶极子系统的演变特征,其活动与暴雨过程有很好的对应.

A Method Based on Singular Spectrum for Separating Synoptic Scale and Subsynoptic Scale Features of Meteorological Field

A method based on principal component reconstruction of singular spectrum for separating synoptic scale and subsynoptic scale features of meteorological field and its calculating procedure are presented and are applied to experiments for separating scales on T BB fields during storm rainfall process over the middle and lower reaches of the Yangtze River in the last ten-day period of July in 1998. The results show that the features of synoptic scale and subsynoptic scale systems of the process are separated clearly. The continuity convective cloud systems along shear line over the Yangtze River are visible in the synoptic scale field. The evolution of dipole system whose motion are corresponding to the storm rain process are shown in the subsynoptic scale field.