Study On Thunderstorm Activity Regularities And Characteristics Of Lightning Disasters In Guangzhou City

As one of the common strong convective weather, thunderstorm has become alarge meteorological disaster after flood and geological disaster. It has importantsignificance for lightning protection and disaster reduction and lightning long time scaleprediction to study the relationship between thunderstorm activity rules and lightningdisasters.The strength of thunderstorm activities is a basic feature of the local climate. Thereare two basic research methods of thunderstorm presently, one is based on artificialobservation data，the other is based on lightning location monitoring network to beautomatic observation data. Taking Guangzhou for example, through the methods oflinear analysis, correlation analysis, M-K mutation analysis and wavelet analysis, thethunderstorm activity regularities and the relationship between thunderstorm activitiesand disasters caused by thunderstorms are mainly studied to expect providing the basisfor lightning climate prediction and putting forward suggestions for lightningprotection.The main research results of this paper are as follows:Firstly, based on daily thunderstorm data for the past fifty years from fiverepresentative observatories in Guangzhou area, the statistical characteristics ofthunderstorm climate are analyzed, mainly for annual, monthly and seasonal rules,including quantitative calculation for climate trend rate and climate tendency coefficient,mutation inspection, cycle, assurance rate for the first and last day of thunderstorm,thunderstorm duration, etc.Secondly, based on lightning location monitoring data, the distribution features oflightning density and intensity are analyzed, including temporal and spatial distributionsof lightning density and current strength.(The current strength is represented bylightning current amplitude).Thirdly, based on Guangzhou lightning disaster examples, the development trendand present features of lightning disasters are analyzed, including lightning accidents overall trend, distribution characteristics of different kinds disasters, personal casualtyaccidents, regional characteristics of accidents happened probability, economic loss,typical features and reasons, etc. for the past seven years.Finally, through a comparative analysis, the relationship between the regularity ofactivities in the thunderstorm and the characteristics of lightning disasters aresummarized and lightning defense suggestions are given. In time, there are goodcorresponding relation among lightning disasters, thunderstorm day and lightningfrequency. Thunderstorm occurs highly during May to September and daily13to19which are the most important periods to protect from lightning damage. In space, thereare not strictly corresponding relation among lightning disasters, lightning frequencyand lightning strength. It also shows that lightning disasters are not only influenced bythunderstorm activities, but also influenced by other factors. Focus on strengthening thesafety work of suburban lightning protection especially in rural area.. Strengthen andimprove weak electric equipments lightning protection in case of lightningelectromagnetic impulse damage.