DISPLAYS OF BIRD MOVEMENTS ON THE WSR-88D - PATTERNS AND QUANTIFICATION

The WSR-88D can readily detect birds in the atmosphere in both clear a ir and precipitation mode, and echo reflectivities of 30-35 dBZ may be realized during heavy migration events or when birds are departing a roosting site. This paper describes the appearance of birds on base re flectivity, base velocity, and velocity azimuth display wind profile p roducts, and presents a calibration curve that relates decibel values of reflectivity to bird migration traffic rates. The recognition of bi rd displays in WSR-88D products is essential for the accurate interpre tation of data gathered by the radar and its use in the development of forecasts. The findings also document the importance of the WSR-88D a s a remote sensing tool for biological studies of birds and insects in the atmosphere and the application of such information in the avoidan ce of bird-aircraft collisions.