应用湿Q矢量分解方法诊断分析“圣帕”(2007)台风暴雨  

DIAGNOSIS OF A RAINSTORM CAUSED BY TYPHOON "SEPAT" (2007) USING THE WET Q VECTOR PARTITIONING METHOD

作　　者：傅灵艳[1] 岳彩军[2] 黄亿[1] 寿绍文[3] 

机构地区：[1]中国民航华北空管局气象中心,北京100621 [2]中国气象局上海台风研究所,上海200030 [3]南京信息工程大学江苏省气象灾害重点实验室,大气科学学院,江苏南京210044

出　　处：《热带气象学报》2010年第5期598-605,共8页Journal of Tropical Meteorology

基　　金：国家自然科学基金项目(40875025、40405009、40205008);上海市自然科学基金项目(08ZR1422900)共同资助

摘　　要：利用WRF中尺度模式模拟了台风"圣帕"(2007)登陆后,减弱成热带低压造成湘赣地区大暴雨的过程,并借助非地转湿Q矢量(Q*)及其分解对这次暴雨过程做了详细的诊断分析。结果表明:800 hPa的Q*矢量散度场的辐合区范围及其辐合强度对降水落区位置及降水强度有非常好的指示作用。将"总"Q*矢量分解成平行和垂直于等位温线两部分后,揭示出了不同尺度的Q矢量散度辐合强迫的不同作用:在暴雨强盛时期,大气以中尺度运动为主,在暴雨发生前、后时期,大气以大尺度运动为主。此外,非地转湿Q矢量散度辐合强迫产生的次级环流也有助于本次暴雨发展与维持。Using the mesoscale model WRF,a heavy rainstorm in Hunan and Jiangxi provinces,caused by typhoon ＂Sepat＂（2007） as it weakened to a tropical cyclone,is simulated,and a detailed diagnostic analysis on the rainstorm is done with the method of wet ageostrophic Q vector（Q＊）.It shows that the divergence area and intensity of the Q＊ vector on 800 hPa are good indicators to the forecast of the falling area and intensity of precipitation.By dividing the total Q＊ vector into two parts,parallel and perpendicular to isotherms,different forcings are revealed of Q＊ vector divergence on different scales： During the intense stage of the heavy rain,the mesoscale motion dominates the atmosphere;during the developing and decaying stages,the large-scale motion plays a predominant role.Besides,the secondary circulation,driven by the divergence of ageostrophic wet Q vector,is helpful in the maintenance of the rainstorm.

关 键 词：天气学 台风暴雨 湿Q矢量分解 诊断分析 次级环流 

分 类 号：P458.121.1[天文地球—大气科学及气象学]