2022年那曲市汛期两次强对流天气的对比分析

Comparative Analysis of Two Severe Convective Weather Events in the Flood Season of Nagqu in 2022

选取那曲地区气象站点地面和探空观测资料,结合FY-4A卫星、新一代天气雷达等探测数据,采用天气学诊断分析方法,对2022年8月2日和9月1日发生在那曲市色尼区两次伴有雷暴的强对流天气过程进行了对比分析。结果表明:两次强对流天气均是副热带高压在高原地区活动且在高压边缘触发对流所致,地面辐合线是两次对流天气过程的触发机制。雷达回波的强弱变化与对流天气的发展演变对应较好,雷达回波强度图仍是预报高原对流天气的重要参考。对流层垂直切变和整层水汽条件是把握对流天气性质的主要依据,对流云团、云顶亮温、上冲云顶等云图特征对强对流天气发展、强度变化和未来走向的预报具有重要的参考意义。

By using the ground and sounding observation data of meteorological stations in Naqu area,combined with the detection data of FY-4A satellite and new generation weather radar,the two strong convective weather processes accompanied with thunderstorms occurred in Seni District,Nagqu City on August 2 and September 1,2022 were compared and analyzed with weather diagnosis and analysis methods.The results show that the two severe convective weather processes were caused by the activity of subtropical high in the plateau region,and the convection was triggered at the edge of the high-pressure system.The surface convergence line was the triggering mechanism for the two convective weather processes.The variation of radar echo intensity corresponded to the development and changes of convective weather.The intensity of radar echo was still an important reference indicator for forecasting plateau convective weather.The vertical wind shear and atmospheric water vapor conditions were the main basis for understanding the nature of convective weather.The cloud clusters,brightness temperature of cloud top,updraft cloud top,and other cloud features had important reference value for the development,intensity,and future prediction of severe convective weather.