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Documentation of historical glacier catastrophes in
Switzerland
The 1818 Giétroz glacier catastrophy is one of the most famous
and most disastrous historical cases in Switzerland. It is particularly
interesting due to the combination of different processes (ice avalanche
with subsequent damming and rupture of the ice dam).
During historical times, glacier catastrophes such as outbursts from
glacial lakes and ice avalanches have repeatedly caused major damages in
the Swiss Alps. Due to the high variety of the involved processes, risks
from such events in glacierized areas have to be estimated on the empirical
basis of historical information which is, therefore, a prerequisite for
any corresponding hazard assessment. All available data of historical glacier
catastrophes is compiled into a documentation since any similar form of
inventory was still lacking for Switzerland. Data was collected from chronicles,
the annals of the Swiss Alpine Club, historical expertises and some other
sources covering a period from the 16th to 20th century. The data is analyzed
in terms of maximum outburst or break-off volume, maximum flood discharge,
runout distance and area affected, damages and protective measures.
The historical sources are far from being homogeneous, thus hindering
the extraction of complete information on every event. All parameters are
examined in view of a refinement or adaptation of existing empirical models.
In addition, the database is linked to a GIS with the objective of analyzing
the spatial
variability of and the areas affected by the events. The data represent
a basis for remote sensing and GIS-based modeling of glacier hazard potentials
in the Swiss Alps.
The documented historical glacier catastrophes in Switzerland as integrated in the GIS-database
http://www.glacierhazards.ch