Precipitation Calibration by Using Kalman Filter to Determine the Coefficients of the Variational Equation
用卡尔曼滤波确定变分方法中的权重系数进行雨量校正

We use the consecutive radar data collected in Fuyang and hourly raingague measurements during HUBEX in 1999 to correct radar-obtained rainfall field by combining variational analysis with Kalman filter. In this method, we determine the coefficients of the variational equation and Euler equation by Kalman filter so we can correct the radar-obtained rainfall from 5:00 June 27 to 18:00 June 27, 1999. In this case, the time between consecutive volume scan is ten minutes. By comparing the rainfall field gained in this way with that through averaging method and old variantional analysis method, we found we can gain the more accurate rainfall field by the new method.