利用WRF 3D-Var同化多普勒雷达反演风场试验研究  

The study of using WRF 3D-Var to assimilate the retrieval wind fields from Doppler radar data

作　　者：杨丽丽[1,2] 王莹[1] 杨毅[1] 

机构地区：[1]兰州大学大气科学学院/甘肃省干旱气候变化与减灾重点实验室,甘肃兰州730000 [2]甘肃省环境监测中心站,甘肃兰州730020

出　　处：《冰川冻土》2016年第1期107-114,共8页Journal of Glaciology and Geocryology

基　　金：国家重点基础研究发展计划(973计划)项目(2013CB430102);公益性行业(气象)科研专项(GYHY201306006);国家自然科学基金项目(41175092)资助

摘　　要：为了将C波段雷达风场资料更好地应用于数值预报模式中,利用两步变分法反演多普勒雷达风场资料,并处理成标准的常规探空资料,以WRF模式及其三维变分同化系统为平台,针对2013年6月19日发生在天水的一次强暴雨过程进行同化雷达反演风的试验研究.试验结果表明：同化雷达反演风场后,对降水预报的改进能维持12 h,尤其同化雷达反演风场后3～9 h效果非常显著;0～3 h作用不是很明显;9～12 h预报具有一定的正作用.另外,循环同化比同化一次效果好,但并不是同化次数越多越好.因此,同化C波段雷达反演风场后,对降水预报具有一定的正作用.In order to apply the wind data of C-Band Doppler radar to numerical weather prediction model better,a two-step variational method is utilized to retrieve the wind field of Doppler radar,and then the retrieval wind is processed into a normal form of radiosonde observation.The retrieval wind is assimilated by the WRF 3D-Var system and the forecast is implemented by WRF model.A heavy rainfall process occurred in Tianshui on 19 June2013 is chosen and four experiments were designed to evaluate the performance of the assimilation of radar retrieval wind.The results show that：assimilation of retrieval wind can extend the positive impact on rainfall forecast up to 12 h,especially the improvement is very significant in the 3-9 h after the assimilation and 9-12 h forecast has a positive effect to some extent.However,the 0-3 h accumulation precipitation forecast after the assimilation is not very well when compared with Experiment CTL.In addition,the cycle assimilation is better than only assimilate once but not the more the better.Therefore,assimilation the retrieval wind data from C-Band Doppler radar is very significant in rainfall forecast.

关 键 词：同化 雷达 反演风 WRF 3D-VAR 

分 类 号：P412.25[天文地球—大气科学及气象学]