| Henan province locates at the middle-lower reaches of Yellow River and the junction belt between Qinling Moutain and Huanghuai Plain. Henan province lies in the transition area between subtropical zone and warm temperate zone. The cisborder terrain include about four kinds of plain, hilly country, knap and basin. The distributing of sever convective weather of western hilly country and eastern plain have obvious seasonal and territorial characters because of terrain actor. Sever convective weather happen frequently in Henan province. Disastrous weather of thunder storm, gale, hail, short-time severe precipitation etc. of different grades will occur everywhere in the province every summer. The disastrous weather work lots of losing on the lives and property of the local people. In this thesis we first analyze the climate geography distribution characters of the strong convection in Henan province. Then we classify the severe convective weather background. By using mesoscale numerical model MM5 we simulated the valley and mountain wind in the clear air on Jun.19, 2006. And we simulated the large area severe convective weather process under different resolution terrain on Jul.19, 2002 in Henan province. The result shows that there were local circulation caused by the difference of terrain dynamical and thermal effect in both the south of Taihang Mountain and the east of Xionger Mountain. The alterative local circulation had obvious effect on the happening and developing of strong convection. The local circulation under the complex landform would affect the distribution of strong convective weather in Henan province.In this paper, aiming at the severe convective weather on Jul. 19,2002, we had analyzed the weather background, detailed physical actors and diagnostic analysis of physical quantity. The result shows that energy stockpiled in the instability stratification under low-level wet air and middle-level dry air released by the influence of upper cold vortex. The analyses of atmospheric remove entropy index shows that the atmospheric order degree above the province increased by the role of atmospheric negative entropy flow. This made for toning up the instability and developing of the strong convection. The analysis of the most favorableness moist entropy differential advection in the upper and low-level shows that upper-levelθ_s advection was less than low-levelθ_s advection. This made atmosphere level above the province become more and more unstable and air convection instability increased. The analysis of vertical shear of wind indicates that upper jet height descended rapidly and its kinetic energy translation strengthened perturbation in the low-level. This was in favor of exploding unstable weather. The analysis of differential potential temperature advection between 300hPa and 850hPa shows that the differential between upper-level cold advection of 300hPa and low-level warm advection of 850hPa on the day was bigger and the forces of cold and warm air were stronger. The station of the temperature field was in favor of increasing instability that caused severe convective process.The analysis of radar echoes of 714CD radar in Zhengzhou indicates that radar echoes developed and strengthened further because of orographic lifting effect after the severe convective echoes went over the Taihang Mountain. After there was a character of hook echo the radar echoes in the shape of belt moved to south rapidly. Where the radar echoes passed by, there were severe convective weather such as thunder storm, gale and local hail etc.
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