Study On The Construction And Application Of WRF-EnSRF Satellite Data Assimilation System

The good initial condition has become more and more important in Numercial Weather Prediction. It's accuracy influence the NWP outcomes directly. Satellite data has the characteristics of being more consistent, covering a wider area and having high spatial and temporal resolution. How to make use of data assimilation to extract the effective observation information of satellite sounding data and to make up for conventional observation networks's lackness of spatial and temporal resolution, to improve the accuracy of numerical prediction, that is a meaningful topic.With the development of data assimilation, Ensemble Kalman Fitter gets more and more attition. It uses a Monte-Carlo ensemble of short-range forecasts to estimate the covaricances of the forecast error. It does not depend strongly on the validity of hypotheses about the linearity of the model dynamics and requires neither a tangent linear model nor its adjoint. In addition, it parallelizes well. Using Ensemble Kalman Fitter to assimilate satellite radiance data has been realized in Canada and USA. But there is still blank in our contry.So, the main aim of the paper is to construct the satellite data assimilation module in WRF-EnSRF assimilation system which established by Wang Shizhang.The following are the main conclusions and results:(1) In this paper, a practical WRF-EnSRF satellite data assimilation system is firstly established in China.(2) By this new assimilation system, the experiment of assimilating AMSU-A and AMSU-B is conducted with a heavy rainfall process accurred at south of China region during 19-20 June 2010. The result shows that the assimilation AMSU microwave radiance data have a certain impact on temperature, wind and humidity fields; for the precipitation forcast, assimilate experiment is superior to control experiment in the rainfall; for TS score, assimilation experiment is better than control experiment at torrential rain level.(3) This experiment shows that WRF-EnSRF satellite data assimilation system can be used to assimilate satellite data.