Doppler radar data assimilation over terrain using Ensemble Kalman Filter

The Ensemble Kalman Filter (EnKF) method is utilized to conduct convective scale data assimilation using Doppler radar observed radial winds and reflectivity. The OSSE-type numerical tests are performed over an idealized north-south elongated mountain similar to the terrain on the western side of Taiwan island. Our experimental designs particularly focus on studying the issues of quantitative precipitation forecast (QPF), and the impact of the blockage of the radar beams by the terrain on the model assimilation/forecasts products. Some preliminary results will be presented.