一次冷锋云系的宏微观物理特征分析

摘要

The characteristics of a cold⁃front cloud during the forest fire on April 17,2011 in Funing county of He⁃bei province, were analyzed at macro and micro scale. Meteorological data of conventional observations, satellite cloud image,Doppler weather Radar data,aircraft observation,and the NCEP reanalysis data were used to analyze the precipitation enhancement potential of this cold⁃front cloud.Macroanalysis shows that the water vapor carried by the cold⁃front cloud is the only source of the artificial precipitation enhancement,which is small in moisture conver⁃gence thus not favorable for precipitation. Microanalysis shows that relatively thin supercooled water area exists in both horizontal and vertical direction of the cold⁃front stratiform cloud system,with certain proportion of small parti⁃cle concentration>20 cm-3 in size.After the feeding operation,the radar echo intensity is enhanced,parameters of the particle concentration,LWC and the mean diameter of particles detected by CAS change significantly. Results show that the cold⁃front cloud has certain precipitation enhancement potential.%利用常规气象资料、自动站资料、卫星云图、CINRAD⁃SA多普勒天气雷达资料以及 NCEP 再分析资料，结合飞行探测数据，对影响2011年4月17日河北抚宁县森林大火的一次冷锋云系进行分析。结果表明：1）宏观分析，过程降水的水汽仅来自冷锋自身所携带的微弱水汽，水汽辐合值较小，不利降水；2）微观分析，冷锋层状云系在水平和垂直方向上存在较薄的过冷水云区，小粒子数浓度大于20 cm－3的云区占一定比例。飞机催化作业后，雷达回波强度增强， CAS （云气溶胶粒子探头）探测的小粒子数浓度、云含水量及粒子平均直径均有明显变化，说明该次冷锋云系有一定的增雨潜力。