黔西南近10 a初夏暴雨形成机理分析  

Weather mechanism analysis of early summer rainstorm over southwest of Guizhou Province

作　　者：王芬 吴古会 郑丹宣 王文勇 吴静 

机构地区：[1]贵州省黔西南自治州气象局,贵州兴义562400 [2]贵州省气象台,贵州贵阳550002

出　　处：《贵州气象》2017年第4期9-16,共8页Journal of Guizhou Meteorology

基　　金：贵州省气象科技开放基金(黔气科合KF[2016]10号);贵州省科技厅科技基金(黔科合基础[2016]1138);黔气科合ZD[2016]01号;中国气象局预报业务关键技术专项(YBGJXM(2017)1A-05);中国气象局预报员专项(CMAYBY2017-065);黔西南州科技局项目(2016-1-15)共同资助

摘　　要：该文利用黔西南州2006—2015年8县站初夏(5、6月)逐小时降水量、Micaps资料,对近10a黔西南初夏暴雨主要环流背景、物理量及云图特征进行了分析,得出如下结论:(1)黔西南初夏暴雨发生时200 h Pa基本都为南亚高压控制;500h Pa主要有高空槽、副高边缘、两高切变、西北气流等;700 h Pa上主要有切变线及低涡,其中切变线有35次,低涡7次,有14次低空急流得到建立;850 h Pa上主要有切变线及低涡,其中切变线21次,低涡19次,有11次低空急流得到建立,急流轴的位置与700 h Pa较为一致;地面上的系统多为辐合线、静止锋或冷锋,其中地面辐合线最多23次,静止锋15次;建立4种概念模型:南支槽型、高原槽型、副高边缘型及高空槽+副高边缘型。(2)暴雨发生前大气中的水汽条件、动力条件、热力条件都是最好的,暴雨发生时大气中的水汽含量变少,低层辐合变弱,上升速度变弱,大气不稳定度被破坏,空气中的能量、热量下降。(3)暴雨云团的源地主要位于贵州西部—云南东部一线,发生次数最多的为云南罗平—富源一带及毕节,次之为六盘水;暴雨云团的路径主要有东南路径、偏东路径、东北路径、西南路径等,其中东南路径最多;暴雨云团生命史在3~20 h之间,平均11.4 h;暴雨云团的初生生成时间在11—23时,主要生成时段集中在午后—傍晚;其中典型MCC占所有暴雨过程的52%,其源地主要为毕节西部,有19个MCC的形成是由多个暴雨云团合并加强最终形成的;MCC云团的最早初生时间为13时,主要初生时段集中在14—17时。Basing on the hourly precipitation data and MICAPS data during 2006-2015 ,the characteristics of the main circulation background, physical quantities and cloud were conducted ,the results are as follows：（ 1 ）91% early summer storm＇ s pressure at 200 hPa level were controlled by south high in south - west of Guizhou province ; upper trough .the subtropical high edge .main projects shear and northwest airflow were the main influence storm system at 500 hPa level;shear line and the low vortex were the main influence system at 700 hPa, the shear line 35 times ,low vortex 7 times, 14 times low level jets were set up;shear line and the low vortex were the main influence at 850 hPa,the shear line 21 times ,low vortex 19 times,11 times low level jets were set up,the position of the jet axis at 850 hPa was consistent with at 700 hPa;the system on the ground were convergence line, stationary front or front ,the ground convergence line was the most ,there are 23 times, stationary front 15 times. Four conceptual models were established： Southern branch trough type, the plateau trough type, subtropical high edge and high upper trough type, subtropical high edge type. （2）Before occurring heavy rain, the moisture condition, dynamic conditions and the thermal conditions in atmosphere were the best, with the heavy rainfall ending, atmospheric water vapor content become less, the low - level convergence and rising speed weak, atmospheric stability was destroyed, the heat energy in the air decrease . （ 3 ） Storm clouds life was between 3 - 20 hours, average was 11.4 hours ; orphaned convective clouds generated in 11：00 to 23： 00, occurring at 15：00 was the most,mainly produce time concentrated in the afternoon to the evening, accounted for 71.4% of the total; the typical MCC accounts for 52% ,the most main resource was Bijie, accounted for 50% of all MCC, 19 MCC were composed of multiple convective clouds ; the earliest time of MCC cloud generating was 13：00 ,main primary session focused on the 14：00 to

关 键 词：初夏暴雨 机理分析 物理量 暴雨云团 

分 类 号：P426.62[天文地球—大气科学及气象学]