Integrating Biophysical and Economic Assessment: Review of Nature-Based Adaptation to Urban Flood Extremes

Abstract

Over the last decade, the potential of nature-based solutions (NBS) has been recognized to support climate change adaptation, by promoting sustainable urban planning. Nevertheless, a wider uptake of such solutions in urban areas faces different challenges and barriers. A comprehensive mapping of available NBS impact assessment methods could help to accelerate this process. There is, however, a lack of comprehensive systematization of economic analysis. This research aims to provide an overview of NBS impact evaluations by assessing how the scientific literature integrates such economic analysis into urban planning adaptation. A systematic review approach has been used to discuss the role of NBS in climate change adaptation. This review presents two main stages. Firstly, it identifies the biophysical–economic assessment of NBS adaptation measures to reduce urban flood extremes in coastal cities. Secondly, the NBS approaches were categorized based on the biophysical benefits (in terms of flood-risk reduction) related to each specific solution and the subsequent economic evaluation of such implementations. This research review revealed a low-level gap of integration between climate change issues and NBS analysis (i.e., it is commonly used as background condition). Most publications provide NBS biophysical impacts assessment, without combining these results with economic evaluation of the flood damages to finally achieve the avoided cost due to the implementation of such solutions. This work shows the growing interest on further research to develop spatially integrated environmental–economic assessment of NBS implementation, by highlighting the needs and opportunities of a trans-disciplinary approach to support policy-making in the framework of urban climate change adaptation.

Urban Vulnerability and Adaptation Strategies against Recurrent Climate Risks in Central Africa: Evidence from N’Djaména City (Chad)

“…On the other hand, floods and strong winds have a large number of negative impacts on urban social and community facilities, housing and the urban environment [14,[32][33][34]. In view of all the above, Bambara et al [35] and Wreford et al [36] consider it necessary for populations to adapt to climate change, as their survival depends on it.…”

“…These results support and confirm the realities observed in Chad's urban territory, since according to the information contained in the third national communication [38], the housing and urban planning sector is under the sway of two main climatic threats, flooding and extremely high temperatures and heat waves, exposing habitats and populations alike. What is more, floods and strong winds have major and numerous negative impacts on collective urban social facilities and the urban living environment [14,32].…”

“…For more than two decades, the international community as a whole has given high priority to environmental issues, with a particular focus on climate change [11], which today represents one of the major challenges for sustainable development [12,13]. As a result of the urbanization process, many urban areas have become vulnerable to climate risks [13,14]. As a result, decision Urban Sci.…”

Adapting Cities to Pluvial Flooding: The Case of Izmir (Türkiye)

“…The Urban Flood Mitigation model considers the potential of porous green areas to reduce the runoff process by absorbing water, slowing surface flows, and creating space for water collection (in floodplains or basins) [40][41][42]. The model calculates the runoff reduction (i.e., the amount of runoff retained per pixel compared to the storm volume) and, for each watershed, provides an estimate of potential economic damage caused by flooding by overlaying information about potential flood extent and built infrastructure [20,43]. In this study, we employed the model without economic evaluation because of limited data and insufficient knowledge to correctly estimate the economic impacts.…”