飞机报资料在0506华南致灾暴雨过程模拟中的应用

THE APPLICATION OF ASSIMILATED AIRCRAFT DATA IN SIMULATING THE HEAVY RAIN OVER SOUTH CHINA IN JUNE 2005

关键词:  华南致灾暴雨  飞机报资料  资料同化  模式模拟

Key words:  heavy rain over South of China  aircraft data  data assimilation  model simulation

摘要:

利用常规和非常规观测资料,对2005年6月18～24日华南地区的一次致灾暴雨过程进行了分析,并对18～19日的过程进行了模拟研究。由于常规观测资料的分析对于描述暴雨的系统结构等方面尚显不足,因此利用GRAPES模式对此次暴雨过程进行了模拟研究。采用不同资料,利用模式同化系统经过12小时的同化,将得出的不同的同化分析场作为模式的初始场,对此次过程进行24小时的数值模拟做对比模拟试验,来对比分析飞机报同化场对于模式预报的改进作用。试验证明,利用有飞机报加入的同化分析场做初始场的模拟结果不仅能够模拟出主要的降水区域,而且降水强度与实况更加吻合,比未加入飞机报的控制试验结果的准确率提高了。飞机报资料的使用对于提高此次暴雨过程模拟效果是可行的、必要的,而且也为该资料用于华南暴雨的预报奠定了基础。

Abstract:

Regular and irregular observational data are used to analyze and simulate a torrential rain over the south of China on 18~24 June 2005.Since the regular data cannot depict the rainfall system fully,GRAPES model is used to simulate this process.Different data are assimilated for 12 hours by its simulating system and different analysis data are obtained.In order to analyze how well the model forecast has been improved with the addition of assimilated aircraft data,these different analysis data are used as the first-guess data to conduct two control numerical simulation tests.From these tests,it's proved that the model that adds aircraft assimilation data can simulate the main region of precipitation,which is more consistent with the observed precipitation than the model that excludes the aircraft data,and that the accuracy rate is also improved.These numerical simulation tests not only show that it's necessary and capable to improve the modeling of this torrential rain process by using aircraft data,but also lays the foundation for forecasting heavy rains in the south of China based on the aircraft data.