WRF模式对中国东南地区的多参数化短期集合预报试验

Experiment of WRF multi-physics short-range ensemble forecasts in southeastern China

本文采用物理过程扰动方法,针对中国东南地区建立了基于Weather Research and Forecas-ting(WRF)模式的短期集合预报系统.利用美国国家环境预报中心全球数据同化系统的高空资料和预报区域内1000多个站点(包括基准站、基本站和一般站)的地面观测资料对短期集合预报系统2010年5、6月份的预报结果进行了检验,分析了物理过程参数化方案和集合平均方法对气象要素预报效果的影响.结果表明:基于WRF模式的短期集合预报系统对我国东南地区高空及地面要素有一定的预报能力.从单个模式成员和集合平均的结果来看,在整个预报时段(60h)内都能较好地预报;不同高度上的气象要素和不同量级的降水对物理过程参数化方案的敏感性不同,预报效果也存在差异.集合平均方法对于大部分气象要素场的预报效果超过单个模式成员.

Using perturbed physics method,a short-range ensemble forecasting system based on Weather Research and Forecasting（WRF）model was built for southeastern China. The forecasted results of May and June 2010 were verified against the upper-level fields from National Centers for Environmental Prediction Global Data Assimilation System and surface observations from more than 1000 stations（including base stations, basic stations and general stations）in the forecast domain. An analysis of how physical parameterization schemes and ensemble mean approach affect the forecasting performance was done. The results showed that WRF model performed fairly well in forecasting the meteorological fields in southeastern China. For the whole forecast period（60 h）, the ensemble forecast system had certain skill in precipitation forecasting,judging from the performance of model members and ensemble mean. Meteorological elements at different pressure levels and precipitation at different thresholds were different in sensitivity to physical parameterization schemes and forecasting performance. For most meteorological fields, ensemble mean performed better than single model member.