Calculations of Ice Crystal Growth

Abstract

The growth rates, and the masses to which the crystals grow at different times, are calculated for various temperatures using the electrostatic analogy and assuming that the crystals follow the experimentally observed growth modes. The additional contribution to growth due to ventilation of the falling crystal is calculated. For small plate-like crystals and for all sizes of columns it is comparable with the growth by diffusion alone, while for larger plate-like crystals ventilation predominates. Peaks in the growth rate occur at temperatures of about ?5 and ?15C as a consequence of the high axial ratio of the crystals characteristic of these temperatures (needles and dendrites, respectively). At other temperatures, calculated growth rates do not differ widely from those obtained by assuming a spherical ice particle.