An Analysis of Accreted Drop Sizes and Mass on Rimed Snow Crystals

Abstract

A classification of the degree of riming of snow crystals is established, based on a visual rating and expressed on a scale ranging from 0 (unrimed) to 5 (graupel). For 84 individual snow crystals collected from six cases over three winters, the size distribution of the accreted cloud droplets is studied. Relationships between the degree of riming and quantitative parameters, namely, the total number and mass of accreted cloud droplets and especially the rimed mass fraction of a snow crystal, are presented. These new relationships may be a powerful tool to estimate the aforementioned parameters by rating only the degree of riming of a snow crystal.