IWATA Shuji Tokyo Metropolitan University, Department of Geography, Professor, 大学院・理学研究科, 教授 (60117695)
FUJITA Koji Institute for Hydorospheric-Atomspheric Sciences, Research Associate, 大気水圏科学研究所, 助手 (80303593)
NAKAWO Masayoshi Institute for Hydorospheric-Atomspheric Sciences, Associate Professor, 大気水圏科学研究所, 助教授 (90142695)
CHIKITA Kazuhisa Hokkaido University, Graduate School of Science, Associate Professor, 大学院・理学研究科, 助教授 (70142685)
KOHSHIMA Shiro Tokyo Institute of Technology, Faculty of Bioscience and Biotechnology, Associate Professor, 生命理工学部, 助教授 (60183802)
Glacier inventory of east Nepal was compiled from maps, aerophotographs and field research. From analysis of the inventory data, it was clarified that glacier shrinkage was distinct in eastward region, where effect of summer monsoon is stronger. Large glaciers, which are covered with supra-glacial moraine, were observed on Khumbu Glacier in east Nepal and Lirung Glacier in central Nepal. Glacier thickness has been decreasing 1-2 m/year ; the rates have been increasing in recent several years during last 25 years. For small glaciers, which are free from supra-glacial moraine, Glacier AX010 in east Nepal and Rikha Samba Glacier in west Nepal have been monitored since 1970s. It was identified as shrinkage of these glaciers was accelerating and the shrinkage was stronger than other glaciers in the world. Possibility of disappearance of Glacier AX010 in 21c was predicted. To reconstruct the past environmental change, snow/ice cores and tree-ring samples were collected and have been under analyses.
In Bhutan Himalayas, the first cooperative study was realized on glacier shrinkage and glacier lakes variations with Royal Government of Bhutan. It was clarified that glacier shrinkage in Bhutan was distincter than that in Nepal, and danger of glacier lake outburst flood was increasing.
Observations to develop the model of glacier variation were also carried out for the future prediction. Glacier thickness which is important parameter of glacier dynamics was observed successfully with an ice radar in thick supra-glacial moraine zones on Khumbu Glacier and Lirung Glacier. Effect of the supra-glacial moraine on glacier melt was studied by heat balance measurements ; melting mechanism of large glaciers was well understood and the results have been utilized for the modeling. Moreover, automatic meteorological records were obtained in Khumbu, Hidden Valley and Shorong regions, Nepal and also in Bhutan for the basic analyses on the relation between climate and glacier variations.