卫星资料在强对流性天气诊断分析中的应用

针对由切变线云系发展合并形成的对流复合体进行分析,探讨卫星资料在强对流性天气诊断分析中的应用,揭示切变线影响下的强对流天气特征。结果表明,此次强对流性天气过程是高空西北气流控制下低层切变线影响造成的;上冷下暖的层结导致对流旺盛,致使雷电产生,低空急流发展加强,保证了山东水汽供应,导致暴雨产生。低层深厚的南方暖湿气流向北推进,其北部边缘为湿舌和高能舌区,大气层结不稳定;动力场上,山东北部为暖切变线,风向辐合和风速辐合,造成强烈的垂直运动。此次切变线暴雨受2个对流云团影响,一个是8日01：00低空急流生成的对流云团,04：00移至鲁中南部发展成对流辐合体MCC;第2个是在鲁西北低层暖切变线对应的对流云团,与鲁中南部的MCC合并成一个强大MCC影响整个山东;这次强对流性天气主要是由第2个切变线对流云团生成合并,延长并加强了第1个MCC持续的生命史,致使强对流性天气的生成。

Application of Satellite Data in Diagnosis and Analysis of Severe Convective Weather

Convection compound formed and developed by shear line cloud system were analyzed,the application of satellite data in the analysis of severe convective weather diagnosis were discussed to reveal the characteristics of severe convective weather under the influence of shear line.The results showed that this severe convective weather process was generated by the influence of shear line of lower layers under the control of northwest airstream in the high;the stratification of up cold and low warm resulted in strong convection,and generated thunder and the stronger of low-level jet stream,ensured the supply of rainstorm.The stratification of up cold and low warm led to strong convection,resulting in thunder and lightning,strengthened the development of low-level jet,and ensured supply of water vapor of Shandong,finally causing the heavy rain.Low-level heavy south warm and wet airflow went northward,the northern edge of which was wet tongue and high-energy tongue areas with unstable atmospheric stratification;in view of power field,warm shear line located in northern of Shandong,wind direction converged as well as wind speed,resulting in strong vertical movement.Strong warm and wet airflow caused development of inverted trough on the ground.This shear line storm was impacted by two convective clouds.One is low-level jet-generated convective clouds,formed by convective clouds generated in southwest of Shandong at 01:00 am on 8th corresponding with top of low-level southwest warm and wet airflow,which moved to south of central Shandong and formed convective convergence MCC.The other one is the convective clouds corresponding with low-level warm shear line in northwest of Shandong,which combined with the MCC in south of middle Shandong and formed one powerful MCC which impacted the whole area of Shandong Province.The strong convective weather was mainly caused by the generation,combination and extension of the second shear line convective clouds and its strengthening to the continuance of the first MCC,and finally resulted in the generation of strong convective weather.