"2003.3"辽宁暴雪及其中尺度系统发展和演变

利用中尺度数值模式MM5V3．6和6h一次的全球再分析NCEP资料，对2003年3月1-2日发生在辽宁的暴雪过程进行了数值模拟试验，着重分析和讨论了这一过程中中尺度系统的发生、发展和结构演变特征。结果表明：MM5V3．6能够成功地模拟中尺度暴雪的各个要素，由于低空辐合，高空辐散，导致上升运动加强以及低层正涡度中心的产生和维持，由此产生的垂直方向上水汽凝结是此次暴雪的形成机制。

Snowstorm on March 1-2,2003 and the Development and Evolution of Its Mesoscale System in Liaoning Province

Using the mesoscale model MM5V3.6 and the NCEP daily reanalysis data every 6 hours,we numerically simulate the snowstorm on March 1-2,2003 in Liaoning Province. We emphatically analyze and discuss the genesis,development and evolution characters of the mesoscale system during this course. Through the simulation we find that the MM5V3.6 has the ability to successfully simulate each factor in this mesoscale snowstorm. The results show that the convergence of low level air flows and the divergence of upper air flows resut in the strengthening of ascending motion and the genesis and maintenance of the center of low level positive vorticity,therefore the water vapor condensation in the vertical direction is the gensis mechanism of the snowstorm.