一次区域暴雪过程中的等熵位涡分析  

Isentropic Potential Vorticity Analysis of a Regional Heavy Snowfall

作　　者：席世平[1] 寿绍文[1] 范学峰 

机构地区：[1]南京信息工程大学,江苏南京210044 [2]河南省气象台,河南郑州450003

出　　处：《河南气象》2006年第4期17-19,共3页Meteorology Journal of Henan

基　　金：国家自然科学基金项目(40405009;40575022;40205008);江苏省气象局科技开发项目(200406);江苏省气象灾害重点实验室项目(KLME050201);国家重点基础研究发展规划项目(2004CB418301);江苏省自然科学基金项目(BK2005141)

摘　　要：利用等熵位涡理论对2006年1月18～19日河南省大范围暴雪过程进行了天气动力诊断分析，结果发现：低纬低层偏南气流沿熵面向北输送的高位涡与强降雪落区和时间有很好的对应关系，并具有预报指示意义；高纬高层的高位涡穿越等压线形成强下沉气流向南输送，低纬中低层西南暖湿气流引起的高等熵位涡沿等熵面爬升。两者在我省长时间交汇，是强降雪带持续的重要原因。A synoptic dynamic diagnosis of the heavy snowfall process in Henan province from 18 to 19 January 2006 is carried out with the theory of isentropic potential vorticity （IPV）. The results indicate that high IPV transported northwards by lower latitudes, lower layers and Southward flow is closely associated with heavy snowfall area and time, which can be a significant predictor. High IPV from higher latitudes and higher layers traversing the isobars becomes a strong sinking flow and transports southward; high IPV from lower latitudes, middle -lower layers, and southwestward warmmoist flow uplifts along the isentropic surface. They meet in Henan province for a long time, which counted for the persistency of the heavy snowfall band.

关 键 词：暴雪 等熵位涡 水汽辐合 

分 类 号：P458.3[天文地球—大气科学及气象学]