摘要
在分析美国局地分析预报系统(LAPS)和GRAPES_Meso数值预报系统,实现GRAPES-LAPS接口的基础上,通过两种数据融合方案,即GRAPES/LAPS方案(简称LAPS方案)和GRAPES/3DVAR方案(3DVAR方案),对2008—2010年华南地区的28个个例的地面、探空常规和加密资料,以及多部多普勒天气雷达数据等融合、同化,开展两种方案的对比模拟试验。结果表明:LAPS方案获得的初始场,水汽条件有所改善,其辐合辐散相耦合触发中小尺度系统发展加强的中尺度环境场,有助于提高模式对强对流天气的预报能力。两种方案的24 h要素场均方根误差检验结果和降水TS评分大体相当,但28个个例中,LAPS方案报出了10个暴雨,而3DVAR方案只报出了5个,LAPS方案的中雨、大雨和暴雨的24 h降水预报TS评分要略好于3DVAR方案相应预报的TS评分,表明LAPS方案对强降水的预报较3DVAR方案有一定改进。
The local analysis and prediction system （LAPS） is widely applied, providing fast comprehensive anal- ysis products for forecasters and assimilating various observational information. GRAPES_Meso is a new generation of global/regional assimilation and prediction system, developed by Chinese Academy of Mete- orological Sciences, and has been used in operation and research. However, LAPS itself does not provide any interface system with GRAPES_Meso. Based on the investigation of LAPS and GRAPES_Meso, the output data of LAPS are used as the ini- tial condition of GRAPES_Meso model （GRAPES-LAPS）, and compared with the original initial scheme of GRAPES_Meso model （GRAPES-3DVAR）. Twenty-eight rainfall events in Southern China from 2008 to 2010 are simulated with the two initial schemes, which both assimilate data including 14 Doppler radar observations, 30 radiosonde observations and about 530 surface observations. The results show that the initial fields obtained by the GRAPES-LAPS scheme accurately represent the moisture fields and meso-scale environmental circulations. The simulated moisture and convergence at low level by the GRAPES-LAPS scheme are stronger than the results of the GRAPES-3DVAR scheme, and these initial fields are beneficial to improve the GRAPES_Meso model simulation. The mean square er- ror （MSE） and threshold scores （TS） of two schemes of the twenty-eight rainfall events are equivalent, but ten rainstorm events are accurately simulated by using GRAPES-LAPS scheme and only five rainstorm events are accurately simulated by GRAPES-3DVAR scheme. The TS scores of moderate rain, heavy rain and rainstorm by the GRAPES-LAPS scheme are a little better than those of the GRAPES-3DVAR scheme, indicating that the GRAPES-LAPS scheme is more suitable to forecast strong rainfall events than the GRAPES-3DVAR scheme.
出处
《应用气象学报》
CSCD
北大核心
2013年第2期162-170,共9页
Journal of Applied Meteorological Science
基金
中国气象科学研究院灾害天气国家重点实验室课题(2008LAWS-Z103)
