MEASUREMENT OF FALLING MOTION OF SNOWFLAKES USING CCD CAMERA

• Main Authors: ムラモト ケンイチロウ, マツウラ コウキ, シイナ トオル, エンドウ タツオ, コニシ ヒロユキ, Ken'ichiro MURAMOTO, Kohki MATSUURA, Toru SHIINA, Tatsuo ENDOH, Hiroyuki KONISHI
• Format: Report
• Language: English
• Published: Department of Electrical and Computer Engineering, Faculty of Technology, Kanazawa University 1992
• Subjects: Polar meteorology and glaciology; Proceedings of the NIPR Symposium on Polar Meteorology and Glaciology
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=3739; http://id.nii.ac.jp/1291/00003739/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=3739&item_no=1&attribute_id=18&file_no=1

The horizontal and vertical falling motions of snowflakes were imaged by two CCD cameras. These images were analyzed by an image processor and a computer. The size and position of each snowflake were measured every 1/30 s from their two images. There were three patterns in falling motion of snowflakes : rotational motion, swing motion and straight motion. The angular velocity of smaller radii of rotational motion was faster than that of larger ones. On the other hand, the radius of rotational motion didn't depend on snowflake size.