一次典型暖区暴雨的中尺度系统分析

摘要

[Objective ] One meso-scale system of rainstorm in the warm zone in Nansha area during June 8 and 9 in 2009 was studied. [ Meth od] By dint of routine meteorological observation dala,NCEP reanalysis data,FY-2C TBB,and wind line data etc. ,the circulation situation, physics field,and the activity of convection system of meso-scale of one rainstorm in the warm zone of Nansha during June 8 -9 in 2009 were expounded so as to explore the causes of such rainstorm. [ Result] The rainstorm had distinct convection nature,with large precipitation intensi ty,uneven distribution,and short timeliness. Most precipitation centered in 5 hours. And the rainstorm in the warm zone was directly Feinted to the activity of meso-conveclive system and was resulted from middle β scale convection system ( Mβ css). The flux field of the high layer of convection layer had fine absorption effect. Coordinating with the southwest and south field at middle and low 500 and 850 hPa in the middle and lower layer to converge around the Zhujiang Della,it provided unstable condition and humidity tor the rainstorm in Nansha area. The advan tageous combination of flux in convective layer, vortex and vertical speed field and the sufficient water supply provided dynamic and water vapor guarantee for the generation of rainstorm in the Nanshan area. The vertical speed of < -0.3 m/s reflected the beginning of precipitation and the smaller the vertical speed was, the stronger the precipitation intensity became. [ Conclusion] It provided reference for the report of rainstorm of such kind in the future.%[目的]研究2009年6月8～9日南沙区一次典型暖区暴雨的中尺度系统.[方法]利用常规气象观测资料、NCEP再分析资料、FY-2C卫星红外亮温(TBB)、风廓线仪资料等,对2009年6月8～9日南沙区一次典型暖区暴雨的环流形势、物理量场、中尺度对流系统的活动进行分析,探讨此次暴雨的成因.[结果]此次暴雨过程具有明显的对流性质,降水强度大、分布不均、时效性短,大部分降水集中出现在5h内,且此次暖区暴雨过程与中尺度对流系统的活动直接相关,是由中β尺度对流系统(Mβcss)直接影响造成的.对流层高层辐散场起到了良好的抽吸作用,配合中低层500与850 hPa一致的西南与偏南流场在珠江三角洲附近辐合,为南沙区的暴雨提供了不稳定条件和湿度条件；对流层散度、涡度及垂直速度场的有利配合以及较充足的水汽输送为南沙区暴雨的发生提供了动力及水汽保证；＜-3.0 m/s的垂直速度反映了降水的开始,且垂直速度越小降水强度越强.[结论]该研究为今后此类暴雨预报工作提供一些参考.