摘要
2010年9月7日苏皖北部出现了暴雨—大暴雨,局部特大暴雨,这次暴雨过程产生在热带风暴(1009号,玛瑙)在东海北上转向日本以后。利用卫星、雷达和NCEP逐日4次1°×1°资料对天气形势和中尺度对流发展的环境场特征等进行诊断分析表明:位于日本海的热带风暴北部的偏东气流与南下深厚的蒙古高压底部的偏东气流汇合,构成了一支强盛的低空偏东风气流,它向西流向太行山东麓,其分支沿太行山南下时,诱生了位于太行山脉南部切变线东部的涡旋系统。当低涡进入黄淮平原后,在越过渤海的边界层东风急流激发下迅速发展为α中尺度涡旋系统。南方的暖湿气流在涡旋系统边界层东风急流的动力强迫下抬升,不稳定能量释放,导致β中尺度系统发生发展。β中尺度系统的影响和γ中尺度系统的合并导致强降水过程的发生。
After the tropical storm （Agate, 1009） turned northward to Japan, a torrential rainstorm occurred in northern Jiangsu and Anhui on September 7, 2010. The environmental field characteristics of weather situation and mesoscale convection were analyzed with satellite image, radar data and the daily NCEP 1 ° × 1 ° reanalysis data. The results show that two easterly airflows, one from the north of tropical storm located in the Japan sea and the other from the bottom of deep Mongolia high, merged to form a powerful low-level easterly airflow, which flowed westwards to the east side of Taihang Mountain and en- gendered the eastern vortex system of shear line located in the south of the mountain. After entering into the Huanghuai plain, the low vortex was stimulated into meso-α scale vortex system rapidly due to the effect of easterly airflow over the boundary layer from the Bohai Sea. The southern warm-moist airflow was uplifted by the dynamic force from the easterly jet on the boundary layer of vortex system, and the insta- bilitive energy released, which all led to the initiation and development of meso-β scale vortex system. The meso-β scale vortex system and meso-β scale vortex system jointly brought heavy rainfall.
出处
《气象科学》
CSCD
北大核心
2013年第6期656-663,共8页
Journal of the Meteorological Sciences
基金
江苏省科技支撑计划项目(BE2011818)
淮河流域气象开放研究基金(HRB201006)
关键词
暴雨
低空急流
中尺度系统
水汽辐合
Torrential rainstorm
Low-level jet
Mesoscale system
Moisture convergence
