提高月预报业务水平的动力相似集合方法  

The dynamical-analogue ensemble method for improving operational monthly forecasting

作　　者：任宏利[1] 张培群[1] 李维京[1] 陈丽娟[1] 

机构地区：[1]中国气象局国家气候中心,气候研究开放实验室,北京100081

出　　处：《气象学报》2014年第4期723-730,共8页Acta Meteorologica Sinica

基　　金：公益类行业(气象)科研专项(GYHY201406022);国家重点基础研究发展计划973项目(2010CB950404;2013CB430203);国家自然科学基金项目(41375062)

摘　　要：针对基于大气环流模式的月预报问题,提出了一种能有效减小预报误差并提高预报技巧的动力相似集合预报新方法。该方法着眼于动力模式与统计经验的内在结合,在模式积分过程中通过提取大气环流历史相似性信息,对模式误差进行参数化处理,形成多个时变的相似强迫量来扰动生成预报的集合成员。将这一集合新方法应用到中国国家气候中心业务大气环流模式(BCC AGCM1.0),一组10 a准业务环境下回报试验结果显示,相比于业务集合预报,动力相似集合预报方法能有效改进模式对于大气环流的纬向平均、超长波和长波预报,从而有效提高了月平均环流预报技巧(几乎达到业务可用标准)和逐日环流预报技巧,并显著降低了预报误差,合理增加集合离散度,使二者配置关系得以改善,有望在业务预报中应用。Focusing on the monthly forecasting problem based on the Atmospheric General Circulation Model （AGCM）, a method of the dynamical-analogue ensemble forecasting （DAEF） is proposed to effectively reduce prediction errors and increase prediction skills. This method aims to the intrinsic combination of the dynamical model and statistical-empirical methods, which can establish perturbation members for ensemble forecasting by extracting the historical analogue information of the atmospher- ic general circulation, parameterizing empirically model errors and generating the multi-time-independent analogue forcing. Ap- plying this new ensemble method to the operational AGCM in Beijing Climate Center （BCC AGCM1）, a 10-yr monthly forecas- ting experiment under a quasi-operational condition shows encouraging results. Compared with the operational ensemble fore- casts by the BCC AGCM1, the DAEF method is capable to improve effectively prediction skills of the monthly-mean and daily atmospheric circulation forecasts in which the former almost reaches the standard, available in the BCC operation, through ef- fectively improving predictions of the zonal mean, ultra-long waves and long waves of the circulation. The results also show that prediction errors for the DAEF are significantly reduced and its spread of the ensemble members is reasonably increased, indicating an improvement in the relationship between the prediction errors and the spread. This study suggests a big potential application of the DAEF method in the BCC monthly forecasting operation.

关 键 词：月预报 集合方法 动力相似 误差参数化 

分 类 号：P435[天文地球—大气科学及气象学]