Terminal velocity adjustments for plate-like crystals and graupel

Velocity adjustments are evaluated for altitude changes using Reynolds number-Davies number correlations of the form Re = aX^b which have been obtained from empirical fall velocities of ice particles. In general, the altitude adjustment was found to vary with both pressure and temperature, except for a temperature-independent range near b ~ 0.7. A quantitative evaluation of b, using the drag on a sphere, shows that altitude adjustments for precipitation particles are less sensitive to changes in termperature than pressure, and that the net adjustment is reduced by compensation between the two effects. -from Authors