SNOW CRYSTALS AND THE IDENTIFICATION OF THE NUCLEI IN THE NORTHERN UNITED STATES OF AMERICA

Abstract

Abstract Snow crystals are born at high altitudes and grow into various forms while falling through the atmosphere. In this research work, the relations observed among snow crystals were crystal form, nucleus, and temperature and humidity of the mother cloud based on radiosonde sounding data. Almost all crystal forms which are shown in “Snow crystals” by Nakaya (1954) were observed in a winter season at Houghton (Keweenaw Field Station), Michigan which is situated on a small peninsula along the southern shore of Lake Superior. The factors that influence snow-crystal form are mainly the air temperature and the humidity at which the crystal grows. Previously there have been no data for the formation of pyramid-shaped snow crystals in natural conditions. However, in the observations of Houghton, it was found that the pyramid shaped crystals were formed in the clouds at temperatures between −6C and −1OC. This coincides with the condition of growth of artificial snow crystals of the cup and scroll type. Needle...