摘要
利用常规气象观测资料、NCEP1°×1°FNL资料和多普勒雷达、卫星TBB等资料,对2016年6月1—2日和18—19日江西省北部两次对流性暴雨过程进行对比分析。结果表明,高空冷涡、西太平洋副热带高压、中低层急流、高空槽等共同作用导致两次暴雨发生。中层有冷空气影响,低层深厚西南急流维持时,更利于降水的对流性特征维持。两次暴雨过程强降水由低质心较强回波的"列车效应"造成。强降水回波带有多单体风暴和强降水超级单体风暴特征时,强降水效率更高。两次过程水汽收支中水汽通量散度项由正转负,水汽垂直输送项由负转正,中低层水汽辐合将低层大量水汽向上输送至中高层,利于强降水的形成。差动涡度平流中心与上升运动中心吻合,其导致垂直动力强迫,促进扰动不稳定和垂直运动的发展。强上升运动区南北两侧垂直经向环流和反环流的形成,为强暴雨的发生维持提供了持续的强水汽水平输送和辐合抬升条件。
The two convective rainstorm processes in northern Jiangxi during 1-2 and 18-19 June 2016 are compared and analyzed based on the conventional meteorological observation data,NCEP 1°×1°reanalysis data,Nanchang Doppler radar data and satellite TBB data.Results show that：both of the two rainstorms are caused by the interaction of upper cold vortex,subtropical high,low level jet and upper trough.Cold air in the middle level and deep southwest jet in low level are favorable to the maintaining of convective precipitation.The heavy rain during the two rainstorm processes is caused by the train effect of the strong echo in the low center of mass.Multicell and supercell storms in heavy rain echoes are favorable to the high-efficient precipitation.The divergence term of water vapor flux divergence in water vapor budget in the night of June 1st and 18 th transforms from positive to negative.The term of water vapor vertical transportation turns positive from negative,and a large amount of water vapor is transported from low layer to middle and high layer by the low level convergence.The water vapor gradually condenses when it touch cold air,which is conducive to the formation of heavy rain.The differential vorticity advection center is in agreement with the ascending motion center,which forces vertical dynamic and promotes the disturbance instability and vertical movement.The formation of a vertical meridional circulation and a vertical counter circulation at both northand south sides of the strong upward airflow provide sustained strong water vapor transport and water vapor convergence lifting conditions to torrential rain occurrence and maintenance.
出处
《气象与减灾研究》
2016年第4期269-276,共8页
Meteorology and Disaster Reduction Research
基金
2015年江西省气象局重点科研项目"强对流天气的格点化预报方法研究"
2016年省局预报员专项"2015年汛期赣北两次强对流过程对比分析研究"
江西省气象局强对流创新团队(编号:JXQDL20140010)
关键词
暴雨
列车效应
水汽收支
涡度平流
torrential rain
echo train effect
water vapor budge
differential vorticity advection
作者简介
周雨,硕士,工程师,主要从事天气预报业务与研究,E-mail：715089388@qq.com
