【摘要】 2012年7月21-22日,北京地区出现了有气象记录以来一次罕见的特大暴雨天气过程,对当地人民的生命财产造成了严重损失。该文采用新一代中尺度数值预报模式WRFV3.7,对这次极端降水天气过程进行了数值模拟研究,通过模式输出结果对其发生、发展机制进行了对比研究。研究结果表明WRF模式能够较好地模拟出这次暴雨的落区、暴雨演变过程和24h累积降水;本次暴雨过程的大尺度环流背景是典型的华北暴雨环流形势,暴雨过程主要由低空中尺度系统造成,暴雨的落区和强度是由中尺度系统随时间的移动而决定。更多还原

【Abstract】 On 21 July 2012,Beijing suffered a severe rainstorm I,which caused serious damage to the local people’s lives and properties.The high resolution model WRF(Weather Research and Forecast) developed by NCAR is widely used to simulate the extreme precipitation process.In addition to that,the outputs of WRF can well represent the physical mechanism of the severe rainstorm.Therefore,WRF is employed in this paper to simulate the 7·21 severe rainfall in Beijing,and the main results as follows:1) WRF model can well locate the heavy rain fall area,and simulate the cumulative rainfall of 24-hour rainstorm evolution;2) The general circulation of atmosphere of the rainstorm process is a typical circulation situation in north China,and the rainstorm process is mainly caused by low-level mesoscale systems,while rain fall area and intensity is determined by the mesoscale system along with the movement of time.更多还原