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The characteristics of cloud-to-ground(CG) lightning flashes around Chengdu is analyzed by means of three-year observational data from the XDD03A lightning location system.It is found that the majority of CG lightning flashes are positive with a mean intensity of 6045 A,slightly higher than that of negative flashes.The intensity of CG flashes is mostly below 12000 A.The daily variation of CG lightning flashes assumes a form of unimodal undulance,with the peak over 60 times from 18:00 to 21:00 and at 01:00 and the valley below 10 times from 10:00 to 13:00.Lightning flashes occur more frequently at night than in the daytime.The tendency of the daily variation of the positive CG lightning flashes is similar to that of total CG lightning flashes and so is that of the negative CG lightning flashes except some slight fluctuations.The tendency of the monthly variation of the number of the positive CG lightning flashes is similar to that of negative CG lightning flashes.Lightning flashes occur more frequently in June,July and August,while less frequently in April,May,September and October.Good correlation between monthly rainfall and corresponding monthly total CG flashes is found.The lightning density around Chengdu is relatively great,much higher in June,July,and August than in April,May,September,and October.