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Changes in glacier dynamics under the influence of proglacial lake formation in Rhonegletscher, Switzerland
Title: | Changes in glacier dynamics under the influence of proglacial lake formation in Rhonegletscher, Switzerland |
Authors: | Tsutaki, Shun Browse this author | Nishimura, Daisuke Browse this author | Yoshizawa, Takeshi Browse this author | Sugiyama, Shin Browse this author →KAKEN DB |
Issue Date: | 2011 |
Publisher: | International Glaciological Society |
Journal Title: | Annals of Glaciology |
Volume: | 52 |
Issue: | 58 |
Start Page: | 31 |
End Page: | 36 |
Abstract: | To investigate the impact of proglacial lake formation on the dynamics and evolution of glaciers, we measured the ice motion of the terminal part of Rhonegletscher, Switzerland, where a lake formed in 2005. In 2009, the flow velocity near the terminus was >20 m a^[-1]. One of the survey stakes tripled its velocity between 2006 and 2007. Since the lake water pressure was consistently close to the ice overburden pressure, it is likely that the high subglacial water pressure enhanced the basal ice motion. The estimated flow velocity due to ice shearing was negligibly small; almost 100% of the horizontal velocity near the terminus was caused by basal sliding. The longitudinal strain rate was large, 0.064 a^[-1], indicating that much of the glacier thinning was due to ice dynamics. The region of ice flotation adjacent to the lake expanded between 2008 and 2009 as a result of glacier thinning. Accordingly, a huge uplift of the surface was observed in 2009. It is clear from the vertical ice motion as well as visual observations that the marginal part of the glacier began to float. The ice-thinning rate in the studied area from 2008 to 2009 was 3.4 m a^[-1], larger than previous estimates. |
Rights: | © 2011 International Glaciological Society |
Relation: | http://www.igsoc.org/ |
Type: | article |
URI: | http://hdl.handle.net/2115/48171 |
Appears in Collections: | 低温科学研究所 (Institute of Low Temperature Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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Submitter: 杉山 慎
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