After the retreat of Rhonegletshcer behind behind a bedrock ridge, a
proglacial lake has been forming since 2005. The formation of the lake
possibly accelerates the glacier retreat because ice dissipates more
by calving into the lake and enhanced basal ice flow. To investigate
the impact of the lake formation on glacier evolution, we have been
working on the glacier since 2007 with collaboration of ETH,
Zurich. In 2008 summer field season, we drilled 24 boreholes in the
terminal part of the glacier. These boreholes are used for measuring
subglacial water pressure, borehole inclination and vertical
strain. An accurate bedrock map was constructed from the depth of the
boreholes and subglacial sediments were collected using specially
designed devices. On the glacier surface, ice flow and ice melt rates
are measured with high temporal and spatial resolutions. The goal of
the project is to use all these data to predict the future of
Rhonegletscher with the aid of numerical glacier model.
A part of the field activity was carried out with participants of Swiss glacier field course
offered by Graduate School of Environmental Science, Hokkaido
University. Graduate students from many different scientific fields
experienced field work on a glacier. This course is also a program of
International Antarctic
Institute.
