Ukichiro Nakaya

Abstract

Professor Ukichiro Nakaya was one of the best known and internationally prominent scientists in the field of snow and ice research. He died at Tokyo, Japan on April 11th, 1962 after a long illness. Dr. Nakaya was born on July 4th, 1900 at Katayamazu (now Kagashi), Ishikawa-ken, which is on the Sea of Japan. He received his Master of Science degree in 1925 from the Department of Physics of the University of Tokyo and then did additional graduate work in physics at Kings College, London, under Dr. O. W. Richardson from 1928 to 1929. He was granted a Doctor of Science degree in 1931 by Kyoto University. In 1930 he was appointed Professor of Physics at Hokkaido University at Hokkaido, Sapporo, and remained associated with that university during the rest of his life. At the time Dr. Nakaya took over the new department of physics there was a minimum of equipment and few funds available for research. But he did have a microscope and an unlimited number of natural snow crystals during the long winters. From over 3,000 photomicrographs he established a general classification of natural snow crystals. His next step was to try to duplicate nature in the laboratory and from these studies he developed the convective snow-making apparatus and the "Nakaya diagram" of growing conditions for snow crystals. From the shape of a snow crystal, he found, one could determine the meteorological conditions in the atmosphere in which the crystal was formed. In 1940 he was awarded the Japan Academy Prize for his research on snow. His beautifully illustrated book, "Snow Crystals", was published by Harvard University in 1954 and now serves as the classic reference on snow crystal shapes and classification to both artist and scientist. In 1941, through his efforts, the Institute of Low Temperature Science was established at Hokkaido University for studies on snow and ice. At the end of World War II he was instrumental in establishing the Institute of Agricultural Physics for the development ofagriculture in cold regions. A natural teacher, he has lifted many a beginning researcher over seemingly insurmountable obstacles by his patience, understanding, and ability to make the most difficult problem appear simple. In 1952 he was invited to conduct research at the U.S. Army Snow, Ice and Permafrost Research Establishment (since redesignated the Cold Regions Research and Engineering Laboratory). During the two-year period that followed he began his classic study of single crystals of ice, and later frequently visited the United States to continue his studies. He enjoyed field work as well as laboratory research and these studies took him to the top of Mt. Mauna Loa, Hawaii, to the Greenland Ice Cap for four seasons, and to Ice Island T-3. His pre-eminence in the field of snow and ice research was recognized by his election as a Vice-president of the Commission on Snow and Ice of the International Union of Geodesy and Geophysics. ... In 1960 he received recognition of his many talents when he was selected as one of the ten most distinguished men in Japan. He will long be remembered in the professional world through his classic research papers and through his inspiration to his students and colleagues. His many friends will remember him as a wonderful, interesting, and much beloved person who often wrote in his books and paintings, "snow crystals are the hieroglyphs sent from the sky."