江淮地区一次雷雨闪电过程分析和数值试验

Analysis and Numerical Simulation of Thunderstorm and Lightning Process in Yangtze-Huaihe Region

摘要: 本文基于常规气象观测资料，卫星数据资料，闪电定位资料，结合中尺度数值 WRF模式模拟研究了2014年4月16日至17日江淮流域一次雷雨闪电天气过程。分析结果表明，本次过程中触发雷雨闪电的机制是江淮切变线和低层不稳定层结，促进了雷电活动的发生发展。雷暴云团在发展前酝酿阶段闪电频次达到峰值，发展至成熟阶段时闪电次数反而减少。雷暴云团上风方以含负电荷的云水粒子为主，下风方积聚大量带正电荷的冰相粒子。WRF模式能够较好地模拟出降水的强度和落区，地形的影响使降水回波在背风面呈现强弱相间的波状分布，具有典型的地形降水分布特征。

Abstract: Based on the conventional meteorological observations data, satellite data and lightning positioning data, a thunderstorm and lightning weather process are simulated by numerical model (WRF) in Yangtze-Huaihe region during 2014 April 16 to 17. The results show that the generation mechanisms of this thunderstorm and lightning are triggered by flow over topography and under the influence of high-level warm advection and wind shear in horizontal and vertical direction. Thunderstorm clouds in the embryonic stage of development and the frequency of lightning attain its maximum, when developed to a mature stage, however, the number of lightning is reduced. Thun-derstorm clouds mainly contained the negatively charged water particles in the upwind side. However, the ice phase particles exist in the lee wind side. This helps to accumulate a large number of positively charged along the track of thunderstorm. WRF model can simulate the rainfall intensity and its zone, the complex terrain plays a significant role in this precipitation process, and it makes the precipitation to be a wavy distribution at the leeward side, which has a typical distribution of terrain precipitation.