Spatial analysis of lightning distribution in Batu city, East Java in 2017 and its correlation with rainfall

Abstract

Based on topography, Batu city can be categorized as a lightning-prone area. Located at 700-1700 m above sea level with an average temperature of 19°C as well as its location on the slopes of mountains, make this area prone to lightning strikes. Lightning strikes, especially lightning type CG (cloud-to-ground) cause serious impact on objects on the surface of the earth. Therefore, spatial information about the distribution of lightning strike is required to reduce the losses caused by lightning strikes. This research discusses the distribution of lightning strikes in Batu city during 2017 and is able to be used to classify the area based on lightning vulnerability. The lightning data used was obtained from the lightning detector BOLTEK record at Karangkates Geophysical Station during 2017. The analysis of lightning strike distribution was correlated with rainfall data in the area and was also grouped into different season periods including rainy, dry, and transition. kriging interpolation method was used for the spatial analysis to determine a contour map of lightning strikes for each square kilometer. Overall, the analysis showed that the highest frequency of lightning strikes in Batu city in 2017 was during the wet season; furthermore, it was correlated to the rainfall in the area.