Doppler Radar Wind Profiles

In this scientific report, an intercomparison of different implementations of the VAD and VVP retrieval techniques and an extensive verification of Doppler radar VVP wind profiles against radiosonde and Hirlam model profiles are presented. Nine months of wind profile data have been used for the intercomparison and verification. Modules to retrieve wind profiles from Doppler volume scan data using different implementations of the VAD and VVP techniques have been developed, but wind profiles from the Rainbow VVP module have been considered as well. It is concluded that the VVP retrieval technique provides wind profiles with a higher availability and a better quality than the VAD technique. In addition, it is found that the most simple implementation of the VVP technique, i.e., with the fewest wind field parameters, provides the best horizontal wind data. The verification results indicate that the accuracy of the VVP wind profiles generally satisfies the requirements for upper-air wind measurements as provided by WMO. Recommendations for improvement of the Rainbow VVP module which will be used operationally at KNMI are made.