东北区域暴雪天气分析及数值模拟  

Synoptic Analysis and Numerical Simulation of Area Snowstorms in Northeast China

作　　者：白人海[1] 张志秀[1] 高煜中[1] 

机构地区：[1]黑龙江省气象台,哈尔滨150030

出　　处：《气象》2008年第4期22-29,共8页Meteorological Monthly

摘　　要：2007年2月14日和3月6日中国东北先后出现暴雪过程,降雪过程范围之广、强度之大都超出了有历史记录以来的极限,给国民经济和人民生活造成极大的损失。在收集大量降水、T213和地面高空气象报告等资料基础上,分析了东北东部这两场大暴雪过程的环流成因并利用GRAPES进行了数值模拟。这两次暴雪过程由于500hPa上空冷空气强度和入侵路径的差异,分别是由蒙古低槽东移和西南涡东北上(对应地面为蒙古气旋和江淮气旋)引起的,后者的天气形势与东北夏季暴雨的一种形势有很大的相似。GRAPES对这两次暴雪过程模拟的结果表明,不仅能够成功地预报天气尺度的主要环流形势演变和影响系统的移动路径,还能够预报出与主要降雪区域相对应的低空中尺度辐合系统,比仅用高空观测报告分析的结果有很大的改善;对降雪强度变化和落区移动状况也能够很好地作出预报,但是有时预报量有偏大的弱点。可以认为GRAPES提供的各种预报产品对日常业务实时应用是很有价值的。The area snowstorm is a major severe weather in northeast China because it possibly causes enormous losses. There are two area snowstorms in northeast China during February 14- 15 and March 4 - 6 of 2007. Their precipitation intensity and range are all greater than the historical records. By using basic data of precipitation, T213, surface and radiosonde observations, the synoptic situation of the two area snowstorms are analyzed. In addition, with the new generation numerical prediction model GRAPES （Global/Regional Assimilation and Prediction Enhanced System）, the two area snowstorms are numerically simulated, and the results are compared with the observational data. The results of analysis and simulation show that the snowstorm during February 14-15 is caused by eastbound trough over Mongolia （Menggu cyclone） and the snowstorm during March 4-6 is caused by northeastward vortex over Southwest China （Jianghuai cyclone） owing to the difference in the strength and moving route of cold air mass. In a sense the second is resemblance to a weather situation of storm rainfall in the summer. In these processes, the major synoptic system not only is simnlated by GRAPES model successfully, such as formation and movement of southwest vortex, but the mesoscale convergence zone or center is simulated more precisely than observational analysis. But the sim-lation values of the precipitation are greater than the observations. The numerical results show that GRAPES model has a good ability to simulate area snowstorms in Northeast China, and is of good reference to the operational forecasting.

关 键 词：区域暴雪 天气成因 数值模拟 GRAPES 

分 类 号：P426.634[天文地球—大气科学及气象学] P458.121.1