Risk-based damage potential and loss estimation of extreme flooding scenarios in the Austrian Federal Province of Tyrol

Abstract

Abstract. Within the last decades serious flooding events occurred in many parts of Europe and especially in 2005 the Austrian Federal Province of Tyrol was serious affected. These events in general and particularly the 2005 event have sensitised decision makers and the public. Beside discussions pertaining to protection goals and lessons learnt, the issue concerning potential consequences of extreme and severe flooding events has been raised. Additionally to the general interest of the public, decision makers of the insurance industry, public authorities, and responsible politicians are especially confronted with the question of possible consequences of extreme events. Answers thereof are necessary for the implementation of preventive appropriate risk management strategies. Thereby, property and liability losses reflect a large proportion of the direct tangible losses. These are of great interest for the insurance sector and can be understood as main indicators to interpret the severity of potential events. The natural scientific-technical risk analysis concept provides a predefined and structured framework to analyse the quantities of affected elements at risk, their corresponding damage potentials, and the potential losses. Generally, this risk concept framework follows the process steps hazard analysis, exposition analysis, and consequence analysis. Additionally to the conventional hazard analysis, the potential amount of endangered elements and their corresponding damage potentials were analysed and, thereupon, concrete losses were estimated. These took the specific vulnerability of the various individual elements at risk into consideration. The present flood risk analysis estimates firstly the general exposures of the risk indicators in the study area and secondly analyses the specific exposures and consequences of five extreme event scenarios. In order to precisely identify, localize, and characterize the relevant risk indicators of Correspondence to: M. Huttenlau (huttenlau@alps-gmbh.com) buildings, dwellings and inventory, vehicles, and individuals, a detailed geodatabase of the existing stock of elements and values was established on a single object level. Therefore, the localized and functional differentiated stock of elements was assessed monetarily on the basis of derived representative mean insurance values. Thus, well known difference factors between the analysis of the stock of elements and values on local and on regional scale could be reduced considerably. The spatial join of the results of the hazard analysis with the stock of elements and values enables the identification and quantification of the elements at risk and their corresponding damage potential. Thereupon, Extreme Scenario Losses (ESL) were analysed under consideration of different vulnerability approaches which describe the individual element's specific susceptibility. This results in scenario-specific ranges of ESL rather than in single values. The exposure analysis of the general endangerment in Tyrol identifies (i) 105 330 indiv...

Tree‐based flood damage modeling of companies: Damage processes and model performance

“…Flood risk analyses are carried out at different spatial scales including the supranational (global), macro (national), meso (regional), and microscales (local) [ de Moel et al ., ]. Many studies assessing flood risk on the micro to mesoscale model the damage in monetary terms on the basis of factors such as water depth, the contamination of the water or the land use of a certain area [ Apel et al ., ; Falter et al ., ; Gerl et al ., ; Huttenlau , ; Kim et al ., ; Koks et al ., ]. Some studies assessing flood risk, expressed as, e.g., the affected amount of the gross‐domestic product and population, on the meso to macroscale include factors such as demography indices or other socioeconomic indicators to model the impacts of flood events [ Koks et al ., ; Ward et al ., ; Winsemius et al ., ].…”

A spatiotemporal multi-hazard exposure assessment based on property data

“…These results suggest that the spatial occurrence of losses is not so much dependent on the occurrence of specifically large events with high hazard magnitudes but more a result of an increased number of elements at risk in endangered areas . Most of the recent works, however, rely on local object-based studies (Zischg et al, 2004;Fuchs et al, 2012) or aggregated land use data (Bouwer et al, 2010;de Moel et al, 2011;, leading to substantial uncertainties if up-scaled to a larger spatial entity (de Moel and Aerts, 2011;Jongman et al, 2012a). Because of the limited data availability, comprehensive object-based and therefore spatially explicit analyses have thus not been extended beyond the local or regional level (Kienberger et al, 2009;Huttenlau et al, 2010;Zischg et al, 2013), and studies focusing on the national level in mountain regions using such data remain fragmentary .…”

Estimation of insurance-related losses resulting from coastal flooding in France

“…Numerous studies have tried to adjust such models on the basis of damage curves describing the loss (cost or destruction rate) as a function of physical parameters such as water levels, velocity, discharge, etc. (Scawthorn et al, 2006;Messner et al, 2007;Prettenthaler et al, 2010;Huttenlau et al, 2010;Boettle et al, 2011). In the case of coastal flooding, losses could result from the contact of saltwater with buildings -generating salt and corrosion problems -or from the mechanical action of waves or currents in the most exposed areas (André et al, 2013).…”