摘要
利用常规气象资料、1°×1°一日4个时次的美国环境预报中心的FNL再分析资料、0．25°×0．25°的TRMM卫星逐3 h降水再分析资料，从大尺度环流形势、水汽条件、动力条件以及对流不稳定层结等方面，诊断分析“7．18”山东暴雨过程。结果表明，此次暴雨过程具有时间短、强度大、范围广的特征，降水雨带自北向南运动。影响此次暴雨的主要天气系统是东北冷涡、西风槽、西南低涡、低空急流和副热带高压。暴雨过程中湿度条件非常充足，水汽的强烈辐合为此次暴雨提供了直接的水汽条件；对流层低层的强烈辐合、中高层辐散的环流配置形势有利于产生强烈的垂直上升运动，对暴雨的形成提供动力条件；暴雨开始前山东地区上空存在较强的对流不稳定层结，有利于强暴雨的产生。
Abstract
Conventional meteorological data, 1°×1°FNL reanalysis data in National Centers for Environmental Prediction every 4 h and 0.25°×0.25°TRMM satellite precipitation reanalysis data every 3 h were used.Conventional observation data were analyzed to diagnose the‘7.18’ Shandong province rainstorm process in terms of large-scale circulation situation, water vapor condition, dynamic conditions and insta-ble convection stratification.Results showed that the rain gush had the features of short time, strong intensity and wide range, with the rain band moving from north to south.The main influencing synoptic systems to the rainstorm were the Northeast Cold Vortex, westerly trough, southwest vortex, low-level jet stream and subtropical anticyclone, respectively.The humidity condition was abundant, and strong convergence of water vapour supplied the direct moisture condition during the heavy rainfall.The distribution of circulation situation exhibiting strong con-vergence in lower troposphere and divergence at middle and upper tropo-sphere was helpful to the generation of intense ascending motion, thus provided dynamic condition for the rainstorm.Before the rainstorm, the strong instability stratification over Shandong Province was helpful to the generation of the intense precipitation.
国家科技期刊平台
NSTL
维普
万方数据