北京“721”特大暴雨云微物理特征分析

利用非静力中尺度模式WRFV3.2,结合LAPS数据融合系统同化多源观测资料,较好地模拟出了北京"721"特大暴雨的降水演变过程。在此基础上,分析了暖区及冷锋降水阶段的云微物理特征差异。研究表明:暖区降水阶段水物质中雪和雨水的含量明显高于冷锋阶段;水汽大量凝结为云水,进而被雪收集,是雪含量较高的主要原因;霰融化为雨水和雨水蒸发为水汽的正负反馈双重作用下,导致暖区阶段雨水含量明显高于冷锋阶段。

Analysis of cloud microphysical characteristics on Beijing

The mesoscale model WRFV3.2 is uesed to simulate the Beijing "721" exteme rainfall,with the assimilation of multi-source data by using LAPS. The numerical simulation can accurately reproduce its precipitation distribution.On this basis, we analyze the cloud microphysical characteristics between warm sector and cold front stage. Studies have shown that: the content of snow and rain in warm stage was significantly higher than the cold front stage;a lot of vapor condensed into cloud water, and converted to snow; melting of graupel and evaporation of vapor paly the dual role of positive and negative feedback in the warm sector stage that is significantly higher than the cold front stage.