一次降水天气过程的GPS掩星资料在GSI同化系统中的应用

为了探索全球定位卫星观测系统无线电掩星技术(Global Positioning System/Radio Occulta-tion,简称GPSRO)在业务数值预报模式中的应用效果,以美国NCEP(National Centers for Environ-mental Prediction)业务同化系统为平台,对有/无COSMIC(Constellation Observing System for Meteor-ology,Ionosphere and Climate)GPS无线电掩星观测资料进行了一次降水过程的详细的同化对比试验。试验中GPSRO观测算子主要采用了相对简单但计算省时的局地(Local)同化技术。该个例试验表明:COSMICGPS掩星观测对分析影响较大的地区是常规观测资料较稀缺地区(如洋面),因此在这些地区GPSRO资料可以被看作是对常规观测很好的补充。同时还注意到COSMIC GPS RO资料在对流层下层对湿度场分析和预报的影响显著,在对流层中上层对风场分析也产生正面影响。这证实GPS RO资料在业务数值天气预报中应用的有效性,为我国数值预报未来开展业务GPS掩星观测资料同化提供了有益的科学参考依据。

Application and Experiment of GPS Radio Occultation Data in the NCEP GSI System in a Pricipitation Process

In order to study the application of GPS/RO(Global Positioning System /Radio Occultation) technique on the operational numerical weather forecast model,the assimilation with and without COSMIC(Constellation Observing System for Meteorology,Ionosphere and Climate)GPS/RO data by using NCEP (National Center for Environmental Prediction,US) GSI(Grid point Statistical Interpolation) operational system were experimented and compared. In the experiments,the local refractivity operator was applied,which was relativ...