 |
| Titel |
Hazard assessment investigations due to recent changes in Triftgletscher, Bernese Alps, Switzerland |
| VerfasserIn |
P. Dalban Canassy, A. Bauder, M. Dost, R. Fäh, M. Funk, S. Margreth, B. Müller, S. Sugiyama |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1561-8633
|
| Digitales Dokument |
URL |
| Erschienen |
In: Natural Hazards and Earth System Science ; 11, no. 8 ; Nr. 11, no. 8 (2011-08-04), S.2149-2162 |
| Datensatznummer |
250009615
|
| Publikation (Nr.) |
 copernicus.org/nhess-11-2149-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
| 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. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|