Feedbacks between City Development and Coastal Flood Risk Management: A Systems Thinking Approach
Authors: Eggert Anna Lea , Arnbjerg-Nielsen Karsten , Löwe Roland 
Published: February 2023

Human activities have a profound impact on climate and hydrological processes, contributing to changes in the frequency and severity of hydrological extremes and, consequently, growing socioeconomic vulnerability [1]. Rising sea levels, continuous urban development in low-lying coastal areas, and corresponding changes in flood risk have resulted in devastating flood impacts. Different Flood Risk Management (FRM) strategies have been adopted in various socioeconomic contexts and spatiotemporal scales, the most prevalent being structural protection. In recent years, numerous scholars have raised concerns about this approach, as studies have shown that increasing protection levels can increase socioeconomic vulnerabilities e.g., [2]. FRM strategies alter the dynamics of risk manifested in sociohydrological systems, which must be disentangled to avoid unintended consequences.In the &#8220;Cities and rising sea levels&#8221; project, scientists from different research disciplines, including hydrology, architecture, landscape architecture, and urban planning, collaborate to tackle these challenges. Combining multidisciplinary knowledge has been central to exploring the cross-sectoral processes involved in FRM. In the present study, we focused on (1) uncovering the cascading effects, including unintended consequences of FRM, as well as (2) highlighting the potentials for holistic assessments of FRM strategies.Our methods include the development of a Causal Loop Diagram (CLD) model describing critical sociohydrological processes of coastal cities operating at different spatial and temporal scales. We identified dynamic feedbacks between (1) flood risk, urban development and economic wealth, (2) flood risk, urban development and social equity, and (3) flood risk, trust in authorities, and institutional capacity, among others. . Based on the CLD, we analyzed key feedback mechanisms and their manifestation in theory and practice. Further, we explored the impacts of different FRM strategies on these feedback mechanisms to uncover differences in impacts on socioeconomic vulnerabilities and wider cross-sectoral impacts. The presentation will present and explore the conceptual model through semiquantitative analyses (Fuzzy Cognitive Maps (FCMs)) and spatiotemporal assessments using a specific case study. We aim at (1) getting case-specific insights into the dynamics produced by the local interplay of flooding events and socioeconomic processes influencing vulnerabilities, and (2) suggesting pathways for new integrated ways of FRM.References[1] IPCC, Climate Change 2022: Impacts, Adaptation, and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press. In Press., 2022.[2] R. W. Kates, C. E. Colten, S. Laska, and S. P. Leatherman, &#8220;Reconstruction of New Orleans after Hurricane Katrina: A research perspective,&#8221; Proc. Natl. Acad. Sci. U. S. A., vol. 103, no. 40, pp. 14653&#8211;14660, Oct. 2006, doi: 10.1073/PNAS.0605726103/ASSET/C486E9DB-5923-43C0-9881-2B57734F2A7C/ASSETS/GRAPHIC/ZPQ0410637570002.JPEG.