Investigation of darkening process of glaciers and ice sheets

2017 Fiscal Year Final Research Report

• Project/Area Number: 26247078
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: Chiba University
• Principal Investigator: Takeuchi Nozomu 千葉大学, 大学院理学研究院, 教授 (30353452)
• Co-Investigator(Kenkyū-buntansha): 大手 信人 京都大学, 情報学研究科, 助教授 (10233199) ; 中野 孝教 早稲田大学, 理工学術院, 客員教授 (20155782) ; 山口 悟 国立研究開発法人防災科学技術研究所, 観測予測研究領域 雪氷防災研究センター, 主任研究員 (70425510) ; 瀬川 高弘 山梨大学, 大学院総合研究部, 助教 (90425835)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 氷河 / 氷床 / クリオコナイト / 雪氷藻類 / 窒素循環 / シアノバクテリア / アルベド / 地球温暖化

Outline of Final Research Achievements

We investigated the darkening processes of glaciers and ice sheets caused by light absorbing impurities on various glaciers in the Arctic and Asian high mountains, including Alaska, Suntar-Khayata (eastern Siberia), Svalbard, Greenland, Tienshan, and Pamir. Comparison of the algal communities and their darkening effect revealed that there are two processes to darken the glacial ice surface associated with algae. One is the darkening by the bloom of green algae with dark-colored pigments. Another is darkening by the cyanobacteria forming dark-colored cryoconite granules. The darkening observed on the studied glaciers was due to either one. For future work on the bio-albedo studies, we need to determine the environmental factors controlling the algal growth, to create a numerical model to reconstruct the algal temporal change, and to evaluate their quantitative impact on the melting based on a physical model of snow and ice albedo.

Free Research Field

雪氷生物学