Completeness analyses of the Austrian torrential event catalog

Abstract

Natural hazard catalogs provide information on past documented events, often as the most reliable indication to ensure future hazard mitigation performance-influencing both social and economic welfare. For such reasons, knowledge about the completeness is important and allows to define the period for which the historical range of variability of the documented events can be stated. Based on an extensive collection of torrential events in Austria (more than 21,000), a robust completeness analyses is presented, based on historiographic as well as statistical approaches. The analyses are based on a 3 W-standard, "When did it happen?", "What happened?", and "Where did it happen?", for all documented events. Hence, a completeness of the whole torrential event catalog can be assumed, if the yearly number of events is independent of the reporting rate-the number of reported events per year. We further present completeness periods of (i) the documented torrential processes, "floods", "bedload processes", and "debris flows" as well as of (ii) the documented eventintensities, "low", "medium", "high", and "extreme". In a first order analysis, an increase in events for the resulting completion period could not be detected. However, a strong correlation to the total rainfall sum above the 99th percentile seems to be evident.

Reported Occurrence of Multiscale Flooding in an Alpine Conurbation over the Long Run (1850–2019)

“…This archive was systematically organized in data sheets during the 1980s, digitized during the 1990s, and made publicly available via Internet during the 2010s (over 30,000 site events reported to date are available at https: //rtm-onf.ign.fr accessed on 30 December 2021). The same history of torrent surveillance and management is shared by other Alpine countries, for instance, Austria, with the Forest technical Service of the Austrian Torrent and Avalanche Control, which initiated a systematic collection of torrential "flood reports" with the Austrian Forest Act in 1975 [48].…”

Fatalities associated with the severe weather conditions in the Czech Republic, 2000–2019

“…Newspaper reports have served as a vital source in the creation of databases of weatherrelated fatalities to the point that the approach has become quite common practice. They have been used, for example, for Switzerland (Hilker et al, 2009), Portugal (Zêzere et al, 2014), southern France (Vinet et al, 2016), Calabria in southern Italy (Aceto et al, 2017;Petrucci et al, 2018), andMallorca (Grimalt-Gelabert et al, 2020). The results of working with Czech newspaper data over a 20-year period may be influenced by the profound changes in society, both in the media market and in internal changes in the actual newspaper employed.…”

Potential of Documentary Evidence to Study Fatalities of Hydrological and Meteorological Events in the Czech Republic

“…This shows that, even between relatively close countries, but with different natural patterns prevailing, the differences in the numbers and structure of fatalities can be quite substantial. After further supplementation of the preliminary Czech fatality database, there will be ample opportunity for future comparison with the comprehensive Austrian torrential event catalogue (see [35]) to extend our knowledge of HME-related fatalities on a broader central European scale.…”

“…Lightning fatalities and injuries going back to 1852 in the United Kingdom were studied by Elsom [32] and for 1988-2012 by Elsom and Webb [33] (see also [34] for a broader, worldwide overview). Recently, Heiser et al [35] reported the Austrian torrential event catalogue. Since 2016, the European Severe Storms Laboratory publishes annual reports, including the number of fatalities associated with severe weather in particular European countries.…”