Electron-microscope Study of Center Nuclei of Snow Crystals: III

[摘要]  Experimental work was carried out in an igloo, half way up Mt. Tokachi, 1030 m above sea level, in the central part of Hokkaido. One solid nucleus (center nucleus) was observed at the center of snow crystals in 190 cases among 202 samples tested. Combining with the former result obtained by M. Kumai, it was confirmed that almost all snow crystals have detectable nuclei at the center. Electron-microdiffraction patterns were taken with respect to same of the samples. From these patterns and the shape of the nuclei, the material of the nuclei was estimated. Roughly speaking, soil particles occupy 60 % of observed nuclei, sea salt particles 20 %, combustion product or carbon particles 10 %, and 10 % cannot be estimated.

[学科分类] 大气科学