“15·8”川东西南涡暴雨的Q矢量分析  

Q-Vector Analysis of the Southwest Vortex Rainstorm in “15. 8”in Southeast Sichuan

作　　者：张雪琦[1] 白爱娟[1] 

机构地区：[1]成都信息工程大学大气科学学院,成都610225

出　　处：《高原山地气象研究》2015年第3期32-38,共7页Plateau and Mountain Meteorology Research

摘　　要：利用NCEP 1°×1°再分析资料和常规地面观测资料,应用非地转湿Q矢量（Q＊）的理论,对2015年8月16-18日一次川东地区持续性暴雨进行了分析。500h Pa高空槽、700h Pa西南低涡（SWV）和850h Pa低空急流为造成此次持续性暴雨的主要系统。结果表明：（1）Q＊散度的辐合区与未来6小时雨带相对应,能较好地诊断未来6小时雨带的分布,西南涡中心位于辐合区西偏南侧,强降水中心位于辐合区中心南部;（2）西南涡中心和未来6小时雨带分别位于Q＊正涡度区东南侧和西侧,但Q＊涡度诊断能力不如Q＊散度;（3）在西南涡发展阶段,大尺度强迫占主导地位,在西南涡成熟阶段则是中小尺度强迫占主导地位;（4）Q＊散度垂直分布能较好地反映出西南涡的垂直结构,西南涡位于Q＊矢量散度辐合垂直带的西南侧。Based on the conventional surface observation data and the NCEP reanalysis data,a rainstorm process on August16 - 18,2015 in the east Sichuan Province was analyzed by using the ageostrophic wet Q vector（ Q＊）. 500 h Pa upper trough,700 h Pa Southwest Vortex（ SWV） and 850 h Pa low- level jet were the main systems causing this persistent rainstorm. The results show as follows：（ 1） The convergence area of Q＊divergence which can better diagnose the area of future rain- band,is coincided with the rain- band after 6 hours,SWV and the rainstorm center locate west by south and south of the convergence area.（ 2） SWV and the rain- band after 6 hours locate in the southeast and west of the positive vorticity area of Q＊,but the diagnosibility of Q＊vorticity is not as good as Q＊divergence.（ 3） The large- scale forcing is the predominant factor during the developing stage of the SWV,however,the meso- and micor- scale forcing is dominant during the intensifying stage of the SWV.（ 4） The vertical distribution of Q＊divergence can reflects SWV＇s vertical distribution that SWV locates in the south-west of it.

关 键 词：西南低涡 持续性暴雨 非地转湿Q矢量 

分 类 号：P458[天文地球—大气科学及气象学]