新一代天气雷达谱宽资料分析晴空回波特征的探讨

Characteristics of the Spectral Width of CINRAD Clear-Air Echo before Severe Weather

根据广州强对流天气发生前新一代天气雷达(CINRAD/SA)观测的晴空回波谱宽资料,经过数据质量控制和预处理,估算了不同高度的湍流耗散率,发现这次强对流天气过程发生前,低层的湍流耗散率明显增强,揭示了这次强对流天气过程的前兆特征。

A series of severe convective storms affected Guangdong Province and produced disastrous heavy rain in Guangzhou especially on August 11,2004. This paper introduces the elementary formation mechanisms for clear air-echo before severe convection and trys to extract the dissipation rate of turbulent energy 8 from the spectral data of CINRAD/SA in Guangzhou. The results show that the turbulence energy dissipation rate in the low atmosphere layer obviously increased before the severe convective storms occurred, which reveals the precursory character of this weather phenomena.