“95.1”高原暴雪及其中尺度系统发展和演变的非静力模式模拟  

Nonhydrostatic Numerical Modeling for the “95.1” Snowstorm Event and Its Development of Mesoscale System

作　　者：隆霄[1] 程麟生[1] 

机构地区：[1]兰州大学资源环境学院大气科学系,甘肃兰州730000

出　　处：《兰州大学学报（自然科学版）》2001年第2期141-148,共8页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金! (4 97752 71)资助项目

摘　　要：为了对青藏高原暴雪进行深入的数值模拟研究 ,在对 1995年 1月 17～ 18日 (“95.1”)高原暴雪进行天气分析的基础上 ,利用非静力中尺度数值模式 MM5对该次暴雪过程进行了数值模拟 .数值模拟结果和客观分析结果的比较表明 ,非静力中尺度数值模式 MM5有能力再现地面以上大、中尺度环流系统和热力场 ;同时 MM5能够成功地模拟出复杂大地形条件下“95.1”高原暴雪中尺度低涡的发生、发展及结构演变 .模拟的运动场和云微物理量场的时空演变表明 ,垂直运动场与水汽场的耦合是水汽凝结和冻结成雪的运动学条件 ;气旋性涡柱和上升运动及深厚湿舌的耦合是暴雪形成的一种重要动力机制 ;模拟的流场演变表明流场更能表征高原上的中尺度系统 .In order to study the process of snowstorm over Tibetan Plateau in a deepgoing way by numerical simulation,the nonhydrostastic model simulation for “95.1” snowstorm was conducted on the basis of synoptic analysis for 17～18 January 1995(“95.1”) snowstorm. The comparisons between results of simulation and objective analysis have shown that MM5 has the ability to replicate large scale and mesoscale circulation systems and their thermodynamic field. The results of simulation indicate that MM5 can successfully simulate the genesis, development and evolution of structure snowstorm's mesoscale vortex's. The temporal and spatial evolution of simulated velocity and cloud microphysics fields show that the coupling of vertical velocity and vapor distribution is a criteria for vapor condensation and freezing that results in snow. The coupling of cyclonic vorticity and ascending motion as well as deep moist tongue is one of the dynamical mechanisms for the formation of the snowstorm. The evolution of simulated streamline field indicates that the streamline field has played an important role for the mesoscale system and its evolution over the plateau.The results of simulation also show that “95.1”snowstorm's precipitation distribution and intensity were reasonable.

关 键 词：高原暴雪 中尺度系统 非静力模式 青藏高原 数值模拟 成雪机制 降雪模拟 

分 类 号：P426.634[天文地球—大气科学及气象学] P435