An Improved Approach to Calculating Terminal Velocities of Plate-like Crystals and Graupel

Abstract

Measurements of 461 planar crows and 312 graupel reported by Kajikawa have been used to develop equations for calculating the terminal velocity and mass of lump and conical graupel and of planar crystals of a variety of shapes and degrees of riming, the resultant equations being applicable to numerical modeling studies. Because all of the parameters required for the derivation of particle drag coefficients were known, the equations are more accurate than those previously used. The implications of the changed values for terminal velocity for these particle types are discussed with respect to the growth of particles through accretion.