湿位涡子项在华南前汛期两类暴雨中的诊断分析  

Diagnostic analysis of MPV subitem on two types of rainstorm during pre-rainy season in South China

作　　者：吴启树 连东英[2] 刘爱鸣[2] 覃丽 沈新勇[4] 

机构地区：[1]福州市气象局,福州350014 [2]福建省气象台,福州350001 [3]广西壮族自治区气象台,南宁530022 [4]南京信息工程大学气象灾害教育部重点实验室,南京210044

出　　处：《气象科学》2014年第3期317-324,共8页Journal of the Meteorological Sciences

基　　金：国家重点基础研究发展计划(973计划)项目(2013CB430103;2011CB403405);国家自然科学基金资助项目(41375058;41075039;41175065);江苏高校优势学科建设工程资助项目(PAPD);中国气象局预报员专项(CMAYBY2011-022);福建省气象局开放式气象科学研究基金(2013k04)

摘　　要：本文从湿位涡的正压项(ζMPV1)和斜压项(ζMPV2)两子项出发,应用常规资料和NCEP再分析资料,通过动态合成分析法,分别分析ζMPV各子项在华南前汛期连续性锋面暴雨和暖区暴雨过程中的特征,并用双雨带过程进行了验证。结果表明:低层ζMPV2的子项(ζ22),对华南锋面降水诊断能力较强,特别是对强降水分布结构特征及中心位置具有明显的诊断能力,不足之处是其强弱并不能直接指示降水的强弱。锋面强降水中心附近的低层ζMPV1与降水量有一定的反相关性。低层强ζMPV1负值对暖区强降水具有潜势预报能力,但其负中心位置或分布结构不能表征降水中心位置及其分布。ζMPV2及其两子项对暖区暴雨无明显诊断能力。以上所得结论物理意义明确,有助于预报员在实际预报业务中更好地使用湿位涡。Based on the conventional observation data and NCEP reanalysis data, the characteristics of subitem of Moist Potential Vorticity （MPV） was analyzed in a frontal and warm-sector rainstorm event during the pre-rainy season in South China with dynamic composite analysis. The results showed that MPV22 at lower level had an obvious diagnostic ability in frontal rainfall, especially in the distribution characteristics and the location of the rainstorm center, except in the precipitation intensity. The inverse correlation of MPV1 with the amplification of precipitation near the rainstorm center was found out. MPV1 and great negative value at lower level could be considered as the potential forecast function in the warm- sector rainstorm, while whose distribution structure and location of negative center could not reflect center location and distribution of precipitation. MPV2 and its subitems did not have obvious diagnostic meaning of rainstorms in warm sector. The clear physical meaning was concluded in this research, which can help the weather forecaster use MPV better.

关 键 词：暴雨 湿位涡子项 动态合成 诊断分析 

分 类 号：P458.121.1[天文地球—大气科学及气象学]