Morphological features of combination of bullet-type snow crystals observed at Syowa Station, Antarctica

• Main Author: Kunimoto Iwai
• Format: Report
• Language: English
• Published: Faculty of Education, Shinshu University 1986
• Subjects: Antarctic; Syowa Station; The Antarctic; Antarc*; Antarctica; Memoirs of National Institute of Polar Research; Polar Research
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=2074; http://id.nii.ac.jp/1291/00002074/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=2074&item_no=1&attribute_id=18&file_no=1

Morphological features of combination of bullet-type snow crystals replicated at Syowa Station, Antarctica are discussed from observations using a stereomicroscope. Some stereophotomicrographs of them are shown. The number of bullets forming the combination was counted. The bullets with five components were the most frequently observed. The maximum number of components was ten. The angles of their c-axes were measured, and found that about 70°, 55° and 88° or their supplementary angle were predominant. In addition, 64° and 78° were found. These angles may be explained by the CSL theory by T. KOBAYASHI et al. (J. Cryst. Growth, 32,233,1976). Apparent pyramidal faces of bullet crystals are not the crystallographic pyramidal faces; {1011}, but are mere skeleton structures. These findings will be important for discussing the optical phenomena in the Antarctic atmosphere.