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Hazard assessment investigations due to recent changes in Triftgletscher, Bernese Alps, Switzerland
Hazard assessment investigations due to recent changes in Triftgletscher, Bernese Alps, Switzerland
The details and the consequences of the recent retreat of Triftgletscher (Gadmertal, Bernese Alps, Switzerland) have been investigated. Geodetic volume changes indicate a strong decrease since 1929 while the position of the terminus remained practically unchanged until 1990. The role played by calving in the tongue retreat running from 2000 to 2006 is confirmed by means of a mass balance model including a calving criterion. Results show that without calving, it would have taken two years longer for the lake to form than has been observed. The consequences of the ensuing tongue destabilization are surveyed, first with an ice avalanche model and second with a hydraulic study of the potential impulse wave triggered by the impact of the falling ice mass in the lake. Results point out that ice avalanches with volumes greater that 1 × 106 m3 will flow into the lake and that in the worst scenario, a discharge of 400 m3 s−1 is expected to reach the endangered area in Gadmertal 11 min after the break-off. In order to detect surface motion precursors to such ice avalanches, a photographic monitoring system was installed. The results indicate seasonal variations with peak velocity in summer and no significant change during the other months. Spectacular velocity increases were not observed so far.
- Hokkaido Bunkyo University Japan
- WSL Institute for Snow and Avalanche Research Switzerland
- Hokkaido University Japan
- Chemnitzer Werkstoffmechanik GmbH (Germany) Germany
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Alean, J.: Untersuchungen u¨ber Entstehungsbedingungen und Reichweiten von Eislawinen, Mitteilung 74, Versuchsanstalt fu¨r Wasserbau, Hydrologie und Glaziologie der ETH Zu¨rich, 1984.
Bartelt, P., Salm, B., and Gruber, U.: Calculating the densesnow avalanche runout using a Voellmy-fluid model with active/passive longitudinal straining, J. Glaciol., 145, 242-254, 1999. [OpenAIRE]
Bauder, A., Funk, M., and Huss, M.: Ice volume changes of selected glaciers in the Swiss Alps since the end of the 19th century, Ann. Glaciol., 46, 145-149, 2007.
Boyce, E. S., Motyka, R. J., and Truffer, M.: Flotation and retreat of a lake-calving terminus, Mendenhall Glacier, southeast Alaska, USA, J. Glaciol., 53, 211-224, 2007.
Chao, Y.-J. and Sutton, M. A.: Accurate Measurement of Twoand Three-Dimensional Surface Deformation for Fracture Specimens by Computer Vision, in: Experimental techniques in fracture, edited by: Epstein, J. S., 59-93, VCH Publishers, Inc., New York, 1993.
Christen, M., Bartelt, P., and Gruber, U.: An Avalanche Dynamics Program for the Practice, in: Proc. INTERPAEVENT 2002 in the Pacific Rim - Matsumoto, Oct. 14-18, 2, 715-725, 2002.
Dost, M., Vogel, D., Winkler, T., Vogel, J., Erb, R., Kieselstein, E., and Michel, B.: How to Detect Edgar Allan Poe's “purloined letter”-or: Cross correlation algorithms in digitised video images for object identification, movement evaluation and deformation analysis, in: P Soc Photo-Opt Ins, SPIE, Bellington, WA, 5048, 2003. [OpenAIRE]
Fa¨h, R.: Erosion-based dambreak simulation, in: Proc. Second Int. Conference on Hydroinformatics, Zurich, 96, 681-688, 1996.
Farinotti, D., Huss, M., Bauder, A., and Funk, M.: An estimate of the glacier ice volume in the Swiss Alps, Global. Planet. Change, 68, 225-231, doi:10.1016/j.gloplacha.2009.05.004, 2009.
Grischott, R., Anselmetti, F., and Funk, M.: Seismic Survey Lake Trift, Tech. rep., Eawag Du¨bendorf and VAW Zu¨rich, (unpublished), 2010.
- Hokkaido Bunkyo University Japan
- WSL Institute for Snow and Avalanche Research Switzerland
- Hokkaido University Japan
- Chemnitzer Werkstoffmechanik GmbH (Germany) Germany
The details and the consequences of the recent retreat of Triftgletscher (Gadmertal, Bernese Alps, Switzerland) have been investigated. Geodetic volume changes indicate a strong decrease since 1929 while the position of the terminus remained practically unchanged until 1990. The role played by calving in the tongue retreat running from 2000 to 2006 is confirmed by means of a mass balance model including a calving criterion. Results show that without calving, it would have taken two years longer for the lake to form than has been observed. The consequences of the ensuing tongue destabilization are surveyed, first with an ice avalanche model and second with a hydraulic study of the potential impulse wave triggered by the impact of the falling ice mass in the lake. Results point out that ice avalanches with volumes greater that 1 × 106 m3 will flow into the lake and that in the worst scenario, a discharge of 400 m3 s−1 is expected to reach the endangered area in Gadmertal 11 min after the break-off. In order to detect surface motion precursors to such ice avalanches, a photographic monitoring system was installed. The results indicate seasonal variations with peak velocity in summer and no significant change during the other months. Spectacular velocity increases were not observed so far.