Abstract:In order to understand the characteristics of particle size distribution during rain and snow processes, ground-based measurements of particle spectrum using a Parsivel disdrometer were compared among samples obtained in 8 rain processes and 10 snow processes in Hohhot from 2017 to 2019. The results show that both the size distributions of raindrop and snowflake are in good agreement with the Gamma distribution. The spectrum width, peak concentration and corresponding diameter of snow spectrum are larger than those of raindrop spectrum, and the snow cases always have larger particle concentration and scale parameters compared to the rain cases when the precipitation intensities are similar. The parameters μ and Λ of Gamma function correspond to the shape and slope of the spectrum, and they satisfy binomial function relationship during both rainfall and snowfall processes, but the fitting effect is poor during snowfall because of the too large-scale range of snowflake. The particle velocity is smaller for snowflake than for raindrop. The falling velocity of raindrops is mostly concentrated at 2-5 m·s-1, while the falling velocity of snowflake is mostly concentrated at 0.5-2 m·s-1, and closer to the speed curve of unfrozen snowflake in comparison.