| Lightning is one of the most hazardous natural disasters and directly threatens the safety of life and property. Especially, due to widely using the micro-electronic device, the probability of being suffered lightning strokes is becoming bigger and bigger, and economical losses also become huger and huger in nowadays. In sequence, people require more and more highly inspecting, forecasting and avoiding lightning disaster. In recent 20 years, with the rapid development of lightning detection technology, the technique for inspecting cloud-to-ground(CG) lightning in quasi-real time (within several seconds) has been mature, and the technique for intracloud(IC) lightning is also improved each passing day. Nowadays, the national lightning detection networks have been set up in developed countries. The national important project-atmosphere automatic observation engineering is about to start in China. The first-term project of national lightning detection network, which consists of 90 lightning location stations in meteorological branch, will be finished at the end of 2003. Due to intense requirement for severe convective weather and lightning disaster service, the developing lightning detection operation and related research work is in dire need in the critical period. Therefore, it has a very realistic meaning to investigate the lightning characteristic and application to severe convective weather forecasting.In the paper, using the CG lightning data obtained from Shandong lightning detection network in 1998-2002,the CG lightning spatial and temporal characteristic is analyzed systematically. The result shows that negative CG flashes predominate in total CG lightning, and negative lightning is about 6 times as much as positive one. The CG flashes in summer are more than 80% of all CG flashes each year in Shandong Province, and the maximum number of flashes emerges in August. The monthly change about the percentage of positive CG lightning is opposite to that of total lightning. Monthly change of positive mean current is similar to that of percentage of positive CG lightning, whereas the monthly change of negative lightning is relatively small. The diurnal change of CG lightning is obvious, and it generally takes on bi-peak and bi-valley pattern. The two peak values occur at 15:00 and 03:00 respectively, whereas the two valley values occur at 09:00 and 22:00respectively.The mean current of positive CG lightning is slightly bigger than that of negative one. The spatial distribution of CG lightning is concerned with topography. Most of CG flashes concentrate on mountain region of Middle Shandong, Jining, weifang and Dongying which is close to the join of the Yellow River and Bohai bay. Based on the spatial distribution difference of 4 periods (morning, afternoon, the first half night and last half night, respectively), it can be found that the impact on CG lightning activity of surface heating, lower tropospheric jet before dawn and sea wind front.Combined with the real-time data obtained from radar and satellite, a variety of severeconvective weather events were studied in detail, especially the relation between CG lightning and radar and satellite data. The result follows: (1) CG lightning in common thunderstorm with weak convective intensity is active at the developing and mature stages, the negative flash rate begins to decline gradually afterwards. The CG flashes in all lifetime are almost of negative polarity and very rarely positive polarity. However, the CG flash rate in severe convective systems with organized structure is high and has peak value before mature stage. After the weather system getting into mature stage, its CG flash rate begin to decline and its percentage of positive CG lightning begin to go up rapidly meanwhile. Sometimes all the CG flashes produced at dissipating stage are of positive polarity. (2) Based on the analysis of lightning and satellite data, it was found that CG flashes generally occur in the cloud region with TBB<-60℃. Negative flashes mainly occur at the front part of...
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