An innovation method for estimating radar radial‐velocity observation error and background wind error covariances

Abstract

Abstract By using the non‐isotropic form of error covariance function derived for radial‐velocity fields on conical surfaces of low‐elevation radar scans, the conventional innovation method is reformulated to estimate Doppler radar radial‐velocity observation error covariance and background vector wind error covariance from time series of radar radial‐velocity innovation (observation minus independent background) fields. The method is applied to radar radial‐velocity innovation data obtained at the lowest elevation of radar scans for a real case. The results show that radar radial‐velocity observation errors are correlated between neighbouring range gates and between neighbouring beams. The radial‐velocity observation error correlation functions are estimated, along with the observation error variance and background vector wind error covariance functions, by the reformulated method. Published in 2007 by John Wiley & Sons, Ltd.