摘要
应用数值模式结果,选择台风登陆后两个不同时次螺旋雨带中两个强降水中心,对台风螺旋雨带的云结构和降水形成机制进行诊断分析。结果发现螺旋雨带云结构和降水形成机制有如下特点:在9～13 km高空范围内冰晶的非均质核化非常活跃,冰晶转化率高于台风眼壁暴雨数倍,但是冰晶通过贝吉龙过程生长为雪、雪通过凝华增长生长为霰的过程相对台风眼壁很弱,螺旋雨带雨水形成微物理机制以霰粒子融化成雨水(pgmlt)为主,冰相粒子转化率大值区位于垂直上升气流大值区,8 km高度霰收集雪(dgacs)干增长是最主要的冰相粒子生长过程,与北方层状云比较,螺旋雨带暴雨冷云中的凝华过程和撞冻过程非常活跃。螺旋雨带云水凝结过程呈双峰型,位于7～8 km高度冷云区的云水凝结峰值较大,暖云区0.5～1.5 km高度云水凝结峰值次之。
The data of numerical simulation are used to analyze the microphysical structures and the precipitation forming mechanisms for the spiral rain bands of typhoon. Two precipitation centers of different times are chosen as the cases being studied in the paper. The main microphysical characters of the spiral rain bands are as follows. The heterogeneous nucleation is very intense at altitudes 9--13 km, the ice crystal conversion ratio is several times higher than that in typhoon eyewall. However, the deposition processes of ice crystal and snow are very weak. The spiral rain bands are mainly produced by melting graupels （pgmlt）. The graupel grows mainly through accretion with snow microphysical processes （dgacs）. The peak value of the processes ＂dgacs＂ stays at altitude 8 km with big vertical vector. Compared with the stratiform clouds in the northern China, the deposition and accretion processes are very fierce in the typhoon spiral storms due to high moisture content. The profiles of the cloud water condensation processes in the spiral rain bands show a double peak type. The biggest peak stays at altitude 8 km in the cold cloud, and the secondary peak stays at altitudes O. 5--1.5 km in warm clouds.
出处
《气象》
CSCD
北大核心
2013年第2期194-202,共9页
Meteorological Monthly
基金
国家重点基础研究发展计划(2009CB421505)
公益性行业(气象)科研专项(201206051)共同资助
关键词
台风
螺旋雨带
降水机制
数值模拟
typhoon, spiral rain bands, precipitation forming mechanism, numerical simulation
