- 著者
- MATOBA Sumito(的場澄人) MOTOYAMA Hideaki(本山秀明) FUJITA Koji(藤田耕史) YAMASAKI Tetsuhide(山崎哲秀) MINOWA Masahiro(箕輪昌紘) ONUMA Yukihiko(大沼友貴彦) KOMURO Yuki(小室悠紀) AOKI Teruo(青木輝夫) YAMAGUCHI Satoru(山口悟) SUGIYAMA Shin(杉山慎) ENOMOTO Hiroyuki(榎本浩之)
- 出版者
- 公益社団法人 日本雪氷学会
- 雑誌
- Bulletin of Glaciological Research (ISSN:13453807)
- 巻号頁・発行日
- vol.33, pp.7-14, 2015 (Released:2015-12-08)
- 参考文献数
- 20
- 被引用文献数
- 10
During spring 2014, we drilled an ice core on the northwestern Greenland Ice Sheet, recovering a core of total length 225m. We also conducted stratigraphic observations, measurements of the density of the ice core, near-infrared photography of the ice core, preparation of liquid samples for chemical analysis, and measurements of borehole temperature. The pore close-off depth was 60m, and the temperature in the borehole was −25.6°C at a depth of 10m. In addition, we conducted snow-pit observations, ice-velocity and surface-elevation measurements using the global positioning system (GPS), meteorological observations, and installation of an automated weather station (AWS).
- 著者
- ONUMA Yukihiko(大沼友貴彦) TAKEUCHI Nozomu(竹内望) TAKEUCHI Yukari(竹内由香里)
- 出版者
- 公益社団法人 日本雪氷学会
- 雑誌
- Bulletin of Glaciological Research (ISSN:13453807)
- 巻号頁・発行日
- vol.34, pp.21-31, 2016 (Released:2016-09-08)
- 参考文献数
- 30
- 被引用文献数
- 11
Snow algae are cold-tolerant photosynthetic microbes growing on snow and ice. In order to investigate the factors affecting snow algal growth, the temporal changes in algal abundance on surface snow were studied over four winters in an experimental station in Niigata Prefecture, Japan, where seasonal snow is usually present from late December to early April. Snow algae appeared on the snow surface in February, and the initial algae were likely to be deposited on the snow by winds. The timing of the algal appearance varied among years, from early-February in 2011 to late-February in 2015, and is likely to be determined by a period of no snowfall and air temperatures above the melting point. Algal abundance generally increased until the disappearance of snow. The maximum algal concentration was found in 2011, which corresponds to the year when the period from algal appearance to the disappearance of snow was the longest (80days) among the four winters. The results suggest that snow algae keep growing unless snowfall occurs and air temperature drops to freezing point, and that the algal abundance is likely to be correlated with the duration of algal growth. The algal growth curve in 2011 could be reproduced by a Malthusian model with a growth rate of 0.22 d−1.