RETRIEVALS OF HORIZONTAL WINDS FROM SINGLE-DOPPLER CLEAR-AIR DATA BY METHODS OF CROSS-CORRELATION AND VARIATIONAL ANALYSIS

Four methods for retrieval of the horizontal wind field are described and compared using single-Doppler observations of a sea-breeze front m easured during the Convective and Precipitation/Electrification Experi ment. The first method examined is the TREC (tracking radar echoes by correlation) technique similar to the one proposed by Tuttle and Foote . Two other methods, similar to TREC, in which wind vectors are estima ted by minimizing the difference between successive patterns of reflec tivity, are then examined. These methods conceptually link the TREC me thod and the velocity volume processing (VVP) approach to the variatio nal wind retrieval method described here. The variational formulation uses the conservation of reflectivity and the radial momentum equation as physical constraints and in this way it incorporates the concepts on which TREC and VVP are based. The performance of the methods is com pared using the dual-Doppler wind analysis as ground truth. Results sh ow that the variational method can retrieve the wind field with higher resolution than the TREC method.