不稳定能量参数在一次强对流天气数值模拟中的应用  

Application of Instability Energy Parameters to a Severe Convective Storm Forecast

作　　者：张玲[1] 张艳玲 陆汉城[3] 寿绍文[1] 

机构地区：[1]南京信息工程大学江苏省气象灾害重点实验室,江苏南京210044 [2]厦门市气象局 [3]解放军理工大学气象学院,江苏南京211101

出　　处：《南京气象学院学报》2008年第2期192-199,共8页Journal of Nanjing Institute of Meteorology

基　　金：国家自然科学基金资助项目(4077503340405009405702240205008);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资助项目(BK2005141);厦门市科技局科技开发项目(3502Z20064022)

摘　　要：采用常规观测资料和1°×1°NCEP/NCAP再分析资料,运用MM5V3.7高分辨率中尺度数值模式,对2004年7月12日17时30分前后发生在江苏南通的一次强中尺度对流系统(龙卷)进行模拟分析。结果表明:南通上空处在上干冷、下暖湿的大气不稳定层结中。干冷空气侵入与边界层暖湿气流强烈辐合,大量能量释放造成了本次龙卷的发生。运用数值模拟结果,计算了最佳对流有效位能IBCAPE、对流抑制能量ICIN、归一化对流有效位能INCAPE、能量—螺旋度指数IEHI和强对流天气威胁指数ISWEAT等不稳定能量参数。通过分析上述参数的空间分布和在南通上空的时间分布,发现它们对强对流天气的发生有一定反映。The atmospheric unstable energy accumulation and release play a key role in the formation of severe convective weather. A mesoscale severe convective storm with tornado and hails at 1730 BST July 12,2004 in Nantong,Jiangsu Province is analyzed in this paper by using the conventional observational data and the NCEP/NCAR 1 ° × 1 ° reanalysis data. The results show that beore 1730 BST July 12 the stratification was unstable with dry and cold air at the upper level and warm and moist air at the lower level over Nantong, and dry air intrusion and its strong convergence with the warm and moist air in the boundary layer induced the release of unstable energy and the formation of tornado. Based on the numerical simulation results, parameters IBCAPE, ICIN, INCAPE,IEHI and ISWEAT etc are calculated, and it is found that the parameters and indexes were good indicators for the severe weather including this tornado.

关 键 词：对流有效位能 强对流天气威胁指数 强对流天气 龙卷风 干侵入 

分 类 号：P458.2[天文地球—大气科学及气象学]