Climatology tuned reflectivity-rain rate relations

The climatologically-tuned relationships between reflectivity, Z, and rain rate, R, are examined. A method is presented which selects the Z-R relation that assures that the values of R are weighted according to their climatological frequency of occurrence. The method is an extension of the approach suggested by Calheiros and Zawadski (1987). Also, consideration is given to the method of optimizing Z-R relations by matching hourly gage and radar-deduced rain amounts proposed by Smith et al. (1975). These two methods are described and applied to data from Germany and from the GARP Atlantic Tropical Experiment. The differences in the Z-R relations obtained using the two approaches are discussed.