Glacier Hazards: Online-database on historical glacier disasters

Background of the database: The database on historical glacier catastrophes has been compiled on the basis of a variety of sources. The main source were the regular reports on the fluctuations of Swiss glaciers, formerly known as 'Les Variations périodiques des Glaciers Suisses'. Summaries are published annually in 'Die Alpen' (Journal of the Swiss Alpine Club) as well.

Other sources frequently used were ancient records and chronicles, newspaper articles and reports from scientific studies. Since the mid-1980es, short reports from various parts of the world on glacier hazards were compiled by the World Glacier Monitoring Service (WGMS in the volumes 'Fluctuations of Glaciers', ICSI/IAHS/UNEP/UNESCO 1988, 1993, 1998). Scientifically (and glaciologically) correct interpretation of historical sources such as records by local, non-scientifically trained people can be a major challenge and requires sufficient experience in glaciology and history.

In fact, this is a problem that has occasionally emerged when historical sources have been analyzed in natural sciences. When transforming the information thus collected into a digital database an appropriate structure must be found. It should satisfy the requirements of easy extraction of information and of continuous updating.

In the present case, instructions by the Swiss Agency for the Environment, Forests and Landscape (Buwal, Heiniman et al., 1998) on building up a database on historical hazards ('Ereigniskataster' = event register) were taken into account. The name of the glacier represents the key attribute. According to the processes involved, a classification into different events is then made.

Further attributes are event coordinates and date, impact/damage, mitigation measures, sources and a set of numerical parameters such as water volume and peak discharge of lake outbursts or break-off volume of ice avalanches. The variety of sources and of the degree of information on different events implies a relatively high variation in the database with respect to the quantity in each category.