On the Habit of Snow Crystals Artificially Produced at Low Pressures

[摘要] A series of artificial snow-making experiment was carried out in the air at low pressures, and the relation between crystal forms and ambient temperature and pressure as represented by the Ta-p diagram (Fig. 9) was established. It was found that solid hexagonal columns are formed at pressures lower than 70mmHg, which is to be attributed to the slow rate of growth, that is, very slight supersaturation of the ambient vapour. The mode of growth at low pressure may probably be considered to have the same characteristics as the growth under quasi-equilibrium condition.By the aid of the results obtained from the present and previous experiments, we obtain the following scheme as to the snow crystal habit:

[学科分类] 大气科学