为了满足准确分析闪电通道三维发展特征和闪电先导相互作用的需求, 建立了一种利用双站摄像资料重建闪电三维通道的方法, 从两幅在不同位置拍摄到的闪电二维图像上分别获取通道的坐标序列, 利用空间立体几何原理, 寻找两组序列中互相匹配的坐标, 再由匹配的坐标序列重建出最终的闪电三维通道.通过对一次实际观测个例的重建与分析, 验证了重建算法在实际观测中的可靠性, 并对闪电通道的三维长度和二维长度进行了对比, 发现两者差异可达2倍以上, 充分说明了闪电三维特征分析的重要性.
A single two-dimensional (2D) image of lightning channel cannot reflect the real spatial distribution of three-dimensional (3D) lightning channel and is insufficient to meet the needs of accurate analysis on the 3D lightning channel development characteristics and on the interaction between different leaders. A reconstruction method of 3D lightning channel from two-station video observation is established. The 2D coordinate sequence of lightning channel is obtained from each 2D lightning image captured at different positions. The theory of solid geometry is used to match the coordinates from different sequences. Then the 3D lightning channel is reconstructed by the matched coordinates. This method is verified feasibly and reliably by reconstruction and comparative analysis of a real observation case. Finally the 2D lengths and 3D lengths of lightning channels are also compared, and the 3D channel length can be over two times of the 2D channel length, which fully illustrates the importance of the analysis on the 3D lightning channel characteristics.
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