Studies On Temporal And Spatial Variations Of Thunderstorm Day In Jiangxi And Ligntning Disaster In China

Based on data of thunderstorm day, lightning detection system and lightingdisaster, this paper studied the temporal and spatial distribution of thunderstorm inJiangxi province and lightning disaster in China. Results show:(1) The consistent change is the main spatial distribution feature of thunderstormin Jiangxi. The spatial distribution is divided into 4 areas. Thunderstorm day ofJiangxi displays degressive tendency in the long term. For the 4 areas, Clear decenttendency of thunderstorm day is display except the areas IV. Mann-Kendall checkcurve shows that a sudden change of areasⅠhappened in 1980 and another suddenchange happened in areasⅡin 1978. A 6 years period exists from 1960s to themiddle of 1970s in all the 43 years. Each area has different periods from anther.(2) cloud-to-ground lightning in Jiangxi province takes on one wave crest indiurnal variation on a whole. Positive lightning takes 2.7％in 2004, and 4.4％in 2005.The intensity of lightning electric current of most positive lightning distributes withinthe range of 20～80KA(3) The trend of times of lighting disaster is undulating and increasing, summer isthe season when most lighting disaster happen, which takes up 66％of the total years.The equipments of electric power and communication systems destroyed in lightingdisaster take up the biggest proportion of the total.