低层流场非线性相互作用的中尺度特征

THE MESO-SCALE CHARACTERISTICS ABOUT NONLINEAR INTERACTION OF THE ENVIRONMENT WIND FIELD IN THE LOWER TROPOSPHERE

本文着重讨论环境流场自身非线性动力结构产生涡散场之间的相互作用,它使涡散场能量趋于集中,其水平分布也呈现中尺度特征。通过实例分析指出,在对流层低层两个非线性量-ξD和的时、空变化特征与暴雨有一定的关系,说明它们对环境流场初始扰动的形成有不可忽视的作用。为此作者建议可作为暴雨诊断量作用。

With emphasis on their son-linear dvnami-cal structures Of the environmeat wind field, this studv discusses the intor-action between vorticity and divergence field. To concentrate the energies of vorticity and divergence field are the main trend and their horizontal patterns appear in meso-scale char a-cteristics aswell.Based on the analysis of practice cases, time-space changing features of bo-th non-1inear quantifties-D and2 are related to heavy rain. Results indicate that they have significant effects on the formation of lower level initial disturbances. Therefore the author suggests that those two quantities may be used as the daignostic heavy rain processes.