Andreas Burzel

Spatial Modeling of Tangible and Intangible Losses in Integrated Coastal Flood Risk Analysis

This paper describes an integrated spatial modeling concept for flood losses which has been developed within the joint research project “XtremRisK”. For the final step of an integrated coastal flood risk analysis based on the “risk source-pathway-receptor” approach, the “Cellbased Risk Assessment” (CRA) concept is implemented for the spatial modeling of both tangible and intangible flood losses and their aggregation into the so-called “integrated risk”. Finally, all results are utilized for the hazard and risk mapping, which serve as a basis for the decision making on risk management strategies. The different steps of the CRA concept and its applicability for different types of spatial input data are shown in the paper. Furthermore, advantages and limitations of this spatial modeling concept for integrated flood risk analysis are discussed. The practical implementation of the approach is described for the study area Hamburg-Wilhelmsburg (Germany) and the related categories of flood losses. The results show that the newly developed CRA concept is a suitable spatial modeling framework with respect to the comprehensive requirements in this integrated coastal flood risk analysis.

XtremRisK — integrated flood risk analysis for extreme storm surges at open coasts and in estuaries: methodology, key results and lessons learned

A brief overview of the joint research project XtremRisK is given. The project has been focusing on developing/improving/expanding the knowledge, methods and models with respect to (i) physically possible extreme storm surge for current conditions and scenarios for climate change, (ii) failure mechanisms of flood defenses, (iii) assessment of intangible losses (social and ecological) and their integration with direct/indirect economic losses, (iv) reliability analysis of flood defense systems and (v) source- pathway-receptor (SPR)-based integrated flood risk analysis involving both tangible and intangible losses and its implementation for two selected pilot sites (representative for an open coast and an urban estuarine area in Germany). The key results are briefly summarized and the lessons learned for future flood risk studies are finally drawn.

Methods for the Evaluation of Intangible Flood Losses and Their Integration in Flood Risk Analysis

Coastal flooding is one of the devastating natural disasters occurred in the recent past and it is expected to further increase due to the effects of sea level rise and storm surges associated with climate change. Losses from these floods are generally categorized as tangible and intangible depending on whether or not the losses can be easily assessed in monetary values. Compared to tangible losses, relatively few research studies exist where intangible losses are assessed and incorporated into flood risk analysis due to the lack of appropriate evaluation and integration methodologies. In this research study, all the intangible losses are assessed in nonmonetary measures using different approaches which were either adopted from literature or newly developed. Furthermore, an attempt was taken to assess the intangible losses in monetary values. The integration of tangible economic losses with the intangible losses measured in nonmonetary values was carried out within the framework of a multi-criteria analysis (MCA). Moreover, the intangible losses in monetary measures are integrated adopting the concept of cost-benefit analysis. The paper presents the results of the evaluation of intangible losses and their integration with tangible economic losses for the exemplary study carried out in the two XtremRisK pilot sites, Hamburg-Wilhelmsburg, and Sylt Island in Germany.

Extreme Storm Surges and Coastal Flooding: Intangible Flood Losses in Integrated Risk Analysis

German coasts are often affected by extreme storm surges which have already led to major damages along the coastline in the past. The joint research project “XtremRisK” was initiated with the main objective of enhancing the knowledge with respect to the uncertainties of extreme storm surge predictions as well as quantifying exemplarily the flood risk under current conditions and future climate scenarios for two pilot sites in Germany: Sylt Island representative for an open coast and Hamburg for an estuarine urban area. Flood risk is generally determined by the product of the flooding probability and the possible losses associated with the flood event. Flood losses are categorized as tangible and intangible depending on whether or not the losses can be assessed in monetary values. Up to date, intangible loses are not or only partially incorporated in flood risk analysis due to the lack of appropriate evaluation and integration methodologies. This study focuses on developing methodologies for the evaluation of intangible losses due to flooding and for their integration with tangible losses in flood risk analysis