高原山区地形对雷暴云地面电场影响规律的数值模拟

为了在高原山区有效利用雷暴临近阶段的地面电场数据实现雷电的精准预警，搭建了典型雷暴云和基本山体模型，并结合高程数据模拟了真实高原山区地形，然后通过有限元方法研究了高原山区地形对雷暴云产生的地面电场分布特点和演变趋势的影响规律。结果表明：基本山体表面的雷暴云电场会发生畸变，畸变程度与山体形态和观测位置有一定关系；真实地形表面的雷暴云电场分布因为地貌的高低不平出现起伏波动，但整体趋势与平坦地面情况下基本一致；雷暴云临近观测点时近地电场的演变过程呈现先大幅上升再小幅下降的规律，但观测点地形特征会影响电场变化幅度。

Numerical Simulation on Effect of Mountainous Terrain on Ground Electric Field of Thunderstorm Cloud in the Plateau Region

In order to effectively utilize the ground electric field data of approaching thunderstorms to realize accurate lightning warning in the plateau mountainous area, a typical thunderstorm cloud model and a basic mountain model were built, and the elevation data was combined to simulate real plateau mountainous terrain. Then, the finite element method (FEM) was used to study the influence of the plateau mountainous terrain on the distribution characteristics and evolution trend of the ground electric field by thunderstorm cloud. The results show that the electric field of thunderstorm cloud on surface of the basic mountain is distorted, and the degree of distortion is related to the mountain shape and the observation location. The electric field distribution of thunderstorm cloud on real terrain fluctuates due to the uneven surface but the overall trend is basically consistent with that on the flat ground. The evolution of the near-earth electric field presents the law of a large increase and then a small decrease when thunderstorm cloud approaches the observation point. However, the terrain surrounding the observation point can affect the amplitude of electric field change.