A HISTORICAL TIME SERIES OF LANDSLIDE EVENTS IN GERMANY AND ITS APPLICATION IN IMPACT AND VULNERABILITY ASSESSMENT

Landslide impacts on infrastructure and society in the Federal Republic of Germany are associated with direct damage costs of about US$300 million on annual average. Despite the large overall losses due to widespread landslide activity, there is a lack of historical time series and impact assessments, not just for Germany’s low mountain areas, but those of entire Central Europe as well. This paper is a collection of different case studies from Germany that seek a better understanding of landslide impacts and their temporal occurrence. The case studies are based on a catalogue of historical landslide events (n > 1,700) extracted from Germany’s national landslide database. Landslide activity at country level shows a strong increase over time and is accompanied by significant annual variation. Starting from the 1820–1869 period (“pre-newspaper era”), the analyses reveal an almost fiftyfold increase in the number of landslide events per year, with an average of 44.6 events in the 2000–2014 period (“internet era”). There is first evidence that the impacts of landslides at local and regional level vary as a function of public hazard awareness. The case studies illustrate that the awareness of landslide hazards undergoes a rapid temporal change as being subject to societal factors and variable hazard exposure. Consequently, the willingness to invest in landslide mitigation is rapidly decreasing over time, especially in low-hazard periods following several years with significant damages. The paper presents new historical datasets that provide a foundation for assessing landslide hazards and risk in Germany.