一次远距离台风暴雨产生机理分析

利用micaps资料和ncep1°×1°网格资料,分析一次远距离台风水汽引发的暴雨的产生机理,主要分析暴雨产生的能量、台风带来充足水汽对发生机理的贡献,用Q矢量湿锋生函数和一些垂直剖面图分析暖锋锋生及暖锋的位置及它们与暴雨产生的关系。同时,分析一些物理量特征。研究表明,水汽潜热释放是重要的对流能量来源,假相当位温剖面图看影响泰州市为暖锋,水汽潜热释放促使暖锋锋生;持续锋生、锋生过程中的非地转运动强迫出次级环流出现上升运动、锋面加强,并且锋面持续存在导致降水持续较长时间,而形成暴雨;前期中层垂直速度明显,构成中层辐合上升,高层辐散,低层下沉,cape为0,低层对流条件弱,在这样的情况下产生深对流是中上层抽吸起到重要作用。该个例地面自动站涡度看有涡度辐合大值区域的产生对雷暴预报有几个小时的提前量。

Analysis on the Generation Mechanism of A Remote Typhoon Rainstorm

By using micaps data and NCEP 1°×1° grid point data,the generation mechanism of rainstorm which was induced by a remote typhoon water vapor was analyzed.The energy of rainstorm generation and the contribution of sufficient water vapor which was brought by the typhoon to the occurrence mechanism were mainly analyzed.Q vector wet frontogenesis function and some vertical profile charts were used to analyze the positions of warm front frontogenesis and warm front,the relationship with rainstorm generation.Meanwhile,some characteristics of physical quantities were analyzed.The research showed that the water vapor latent heat release was the important convective energy source.Seen from the pseudo-equivalent potential temperature profile chart,the warm front affected Taizhou City,and the water vapor latent heat release promoted the warm front frontogenesis.The ageostrophic motion in the durative frontogenesis and frontogenesis process compelled the secondary circulation to have the ascending motion and the frontal surface reinforcement.Moreover,the frontal surface persistently existed,which caused that the precipitation lasted the long time,and the rainstorm was formed.In the previous period,the vertical velocity in the middle layer was obvious.It constructed the convergence ascension in the middle layer,the divergence in the high layer and the subsidence in the low layer.cape was 0,and the convective condition in the low layer was weak.In the situation,the pumping effect in the middle and upper layers had the important role for the generation of deep convection.Seen from the vorticity in the ground automatic station,the generation of zone where the vorticity convergence was the big value had several hours preact for the thunderstorm forecast.