地面观测资料在西南地区数值预报中的敏感性试验  

Sensitive Experiments of Surface Observation Data in Numerical Weather Precipitation over Southwestern China

作　　者：张利红[1] 杜钦 陈静[1] 肖玉华[3] 

机构地区：[1]成都高原气象研究所,成都610072 [2]重庆市气象科学研究所 [3]四川省气象台

出　　处：《气象》2009年第6期26-35,共10页Meteorological Monthly

基　　金：中国气象局新技术推广项目CMATG2008M26;中国气象局成都高原所开放基金项目LPM200608;基本科研业务费专项BROP200707;科研院所社会公益研究专项2005DIB3J112共同资助

摘　　要：利用3.0版的GRAPES同化系统,针对西南地区2005年7月的夏季降水,开展地面观测资料的同化敏感性试验,对整月天气进行了每日一次的48小时预报,并对该月发生在川渝地区"7.8"大暴雨过程进行对比分析。试验结果表明,在地形复杂的西南地区,利用等压面的GRAPES 3DVAR同化系统同化地面观测资料对降水预报的影响随进入同化系统的地面观测资料疏密程度和同化内容的不同而不同;当模式采用较高分辨率时,同化的地面观测资料越多,对降水预报的改善作用越明显;同化地面观测资料的风速信息可以降低降水预报的空报率,但对漏报率和TS评分改善作用不明显;在几种同化方案中,利用GRAPES 3DVAR同化系统同化地面观测资料的相对湿度和位势高度信息,对降水预报的改善效果最明显。Numerical experiments about the surface observation data assimilation in southwestern China were carried out by use of the GRAPES 3.0 assimilation and prediction system. 0 - 48 h precipitation forecasts of a whole month and a heavy rainfall process that occurred in southwestern China in July, 2005 were analyzed. The main conclusions were as follows： Firstly, the influence of surface observation data assimilation on precipitation forecast varies with the density of surface observation data used and the assimilating information selected in this region; Secondly, when numerical forecast model takes higher resolution, the results of rainfall prediction with all surface observation data, are superior to those with spare surface observation data from GTS; Thirdly, in complex terrain of southwestern China, assimilating wind information of surface observation data can have obvious influence on forecast results, decreases false precipitation ratio and makes little contribution to raising missing precipitation and TS in contrast with not assimilating; Lastly, the scheme of assimilating relative humidity and geopotential height is the best one among these assimilation schemes.

关 键 词：地面观测资料 资料同化 敏感性试验 

分 类 号：P456.7[天文地球—大气科学及气象学] V321.213[航空宇航科学与技术—人机与环境工程]