FLUCTUATION OF δ^<18>O OF SURFACE SNOW WITH SURFACE HOAR AND DEPTH HOAR FORMATION UNDER RADIATIVE COOLING

• Main Authors: ハチクボ アキヒロ, モトヤマ ヒデアキ, スズキ ケイスケ, アキタヤ エイジ, Akihiro HACHIKUBO, Hideaki MOTOYAMA, Keisuke SUZUKI, Eizi AKITAYA
• Format: Report
• Language: English
• Published: Institute of Low Temperature Science, Hokkaido University 1997
• 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=3973; http://id.nii.ac.jp/1291/00003973/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=3973&item_no=1&attribute_id=18&file_no=1

δ^<18>O and major ions of the snow surface layer were measured during hoarfrost formation. In the nighttime, δ^<18>O decreased when surface hoar and depth hoar crystals formed above and beneath the snow surface, respectively, while δ^<18>O increased due to evaporation in the daytime. These results suggested that H_2^<16>O was enriched by condensation of the hoar crystals, whereas H_2^<18>O was concentrated on the snow surface by the evaporation of light H_2O to the atmosphere. Concentrations of major ions were observed to change as well according to condensation and evaporation of water vapor. δ^<18>O of hoar crystals condensed on March 5 to 6 was estimated to be approximately 5‰ lower than that of the original surface layer.