Analysis of lightning-induced electromagnetic fields near rugged terrain in cylindrical coordinates

In this paper, the lightning-generated electromagnetic fields over lossy ground produced by lightning strikes either to flat ground or to rugged terrain are calculated using the 2-D finite-difference time-domain (FDTD) method. In order to find the changing trend of vertical electric fields induced by lightning strike with different height and gradient of rugged terrain, we set the height to 40m, 60m, 80m, 100m and 120m and the width of top to 20m, 40m, 60m, 80m and 100m, respectively. We find the vertical electric field Ez at the top of rugged terrain enhanced and the vertical electric field near the upland reduced. Further more, with increasing height of upland, the vertical electric field rises on the top and falls near the rugged terrain. With increasing gradient of slope, the vertical electric decreases around the upland.