Distribution Characteristic of Severe Convective Thunderstorm Cloud over Qinghai-Xizang Plateau
ZHANG Hongfa1,GUO Sangang1,ZHANG Yijun1,CHENG Guodong1SHI Yunqiang2,PUBU Zhouma3,HOU Zhengjun2(1. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences,Lanzhou 730000, China; 2. Rikaze Region Meteorology Bureau, Rikaze 857500, China; 3. Lhasa Meteorology Bureau, Xizang Autonomous Region, Lhasa 850000, China)
Using the thunderstorm data over QinghaiXizang Plateau in summer ( May to September) from 1950 to 2000, especially the surface and upper weather data, radar echo data in field experiment observation over QinghaiXizang Plateau in recent 50 years, the change characteristics of convective thunderstorm distribution along QinghaiXizang Railway, diurnal variation and life cycle of severe thunderstorm over QinghaiXizang Plateau were analyzed. The results show that the severe thunderstorm weather in summer along QinghaiXizang Railway increased from north to south, the annual mean thunderstorm numbers reach 90, and thunderstorm in May～ September accounts for 97% in whole year. The occurring time of thunderstorm over QinghaiXizang Plateau is mainly at 15:00～22:00 (BLT) and decaying from north to south. The maintain of life cycle of severe convective thunderstorm activity over QinghaiXizang Plateau with ≤1 h makes up over 70% , that of 1～2 h 20%, and 2 h less than 10%.