Lightning Detection System in Korea Meteorological Administration

1. Lightning Network Instrument Lightning occurrence tendency Display Lightning Detection System in Korea Meteorological Administration Seung-Sook Shin, Jeong-Hee Kim, Ki-Ho Chang, Jong-Ho Lee, Duck-Mo Woo Observational Technology and Management Division, Korea Meteorological Administration E-mail : jeonghee@kma.go.kr • Since KMA introduced Lightning Location and Protection (LLP) in 1987, KMA is observing Lightning event occurred in Korea and using in forecaster. • Instrument observing lightning is changed into IMPACT ESP(IMProved Accuracy from Combined Technology Enhanced Sensitivity and Performance) in the early 2000, and used for observing lightning from 2002. • Recently, KMA installed LDAR II(Lightning Detection And Ranging System: Total lightning detection systems) sensor, is observing in-cloud discharge, and is doing the quality control of the data. • Network of lightning detection is composed of 7 IMPACT ESP sensors and 17 LDAR II sensors. (See Fig. 1) Fig. 5 Overlaid display of lightning, radar, and satellite image Fig. 6 The distribution of daily accumulated lightning Fig. 7 The distribution of lightning accumulated for 30 minutes to analyze the track Fig. 9 Mobile warning system for lighting Fig. 8 The display of lighting location Fig. 1 KMA network (● IMPACT, ◇ LDAR II ) • IMPACT ESP sensor • IMPACT ESP sensor detects cloud-to-ground discharge (C-G Lightning). • Detection efficiency and location accuracy is very high because of combining strongpoint of TOA (Time-Of-Arrival) technology and accuracy of MDF (Magnetic Direction Finding) technology. • Three IMPACT sensors are needed for exact location of the lightning. Fig. 11 Monthly number of lightning events for 2002~2007 Fig. 10 Annual number of lightning events for 2002~2007 Fig. 2 IMPACT ESP sensor Fig. 3 The range of lightning detection • LDAR II sensor Fig. 12 The number distribution of lighting in 2007 Fig. 13 The number distribution of lighting days in 2007 • LDAR II sensor uses TOA method. • Using VHF (Very High Frequency) • It can detect every discharge like in-cloud, cloud-to-atmosphere, and so on. • It needs minimum five sensors for three dimension observations and four sensors for two dimension observations. Fig. 4 LDAR II sensor Fig. 14 Monthly mean intensity in 2007 Fig. 15 Monthly polarity frequency of lightning in 2007 • The system collects the real-time data from lightning sensors and displays collected data every 10 minutes. Thereafter, user select data as lightning, satellite, and radar image and can display overlaid data at the monitor. • KMA can track severe weather from displaying accumulated lightning data and analysis the tendency of lightning occurrence through daily accumulated data. • KMA offer every people the real-time position information of lightning on the internet and intranet so that many people simultaneously can analysis the lighting data. • People can magnify the area of lighting occurrence and get the location information like latitude, longitude, and place name by online. • KMA supply the real-time lighting dangerous zone by using mobile warning system for lighting to minimize the damage concerned with natural disaster. Fig. 16 The number of lightning events in (a) spring, (b) summer, (c) fall, and (d) winter 2007