The weather research and forecasting model's community variational/ensemble data assimilation system: WRFDA

A community tool, the Weather Research and Forecasting (WRF) model's Community Variational/Ensemble Data Assimilation System (WRFDA), was developed for and widely used by the Weather Research and Forecasting model's international data assimilation research/operational community. A subset of essential features like conventional observations, three-dimensional variational data assimilation (3DVAR) algorithm, portable, supported, and with good documentation was agreed as the initial basic requirement. The WRFDA system can ingest a wide variety of observation types, in addition to the standard conventional observation types. The WRFDA system directly ingests radiances in the National Centers for Environmental Prediction (NCEP) Binary Universal Form for the Representation of Meteorological Data (BUFR) format. The WRFDA system includes a table of observation errors for each major observation type, as used in AFWA applications of WRFDA. Default synoptic-scale climatological forecast error statistics are also provided for initial setup, testing, and training runs. 58.