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Abstract Exposure to sea-level rise (SLR) and flooding will make some areas uninhabitable, and the increased demand for housing in safer areas may cause displacement through economic pressures. Anticipating such direct and indirect impacts of SLR is important for equitable adaptation policies. Here we build upon recent advances in flood exposure modeling and social vulnerability assessment to demonstrate a framework for estimating the direct and indirect impacts of SLR on mobility. Using two spatially distributed indicators of vulnerability and exposure, four specific modes of climate mobility are characterized: (1) minimally exposed to SLR (Stable), (2) directly exposed to SLR with capacity to relocate (Migrating), (3) indirectly exposed to SLR through economic pressures (Displaced), and (4) directly exposed to SLR without capacity to relocate (Trapped). We explore these dynamics within Miami-Dade County, USA, a metropolitan region with substantial social inequality and SLR exposure. Social vulnerability is estimated by cluster analysis using 13 social indicators at the census tract scale. Exposure is estimated under increasing SLR using a 1.5 m resolution compound flood hazard model accounting for inundation from high tides and rising groundwater and flooding from extreme precipitation and storm surge. Social vulnerability and exposure are intersected at the scale of residential buildings where exposed population is estimated by dasymetric methods. Under 1 m SLR, 56% of residents in areas of low flood hazard may experience displacement, whereas 26% of the population risks being trapped (19%) in or migrating (7%) from areas of high flood hazard, and concerns of depopulation and fiscal stress increase within at least 9 municipalities where 50% or more of their total population is exposed to flooding. As SLR increases from 1 to 2 m, the dominant flood driver shifts from precipitation to inundation, with population exposed to inundation rising from 2.8% to 54.7%. Understanding shifting geographies of flood risks and the potential for different modes of climate mobility can enable adaptation planning across household-to-regional scales.
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Harnessing Community Science to Address Flood Risks and Build Climate Resilience With Nature‐Based Solutions (NbS)—A Case Study From the Quad Cities Region
Abstract Urban regions situated along major river systems are increasingly facing flood risks, driven by the combined effects of rapid urbanization and intensifying climate change. The Quad Cities region, comprising Davenport and Bettendorf in Iowa, and Rock Island, Moline, and East Moline in Illinois, is vulnerable to flood hazards caused by extreme precipitation, fluvial surges, and extensive impervious surfaces. Historical records indicate 10%–20% increase in annual precipitation, with a rise in high‐intensity rainfall. Projections under the SSP5‐8.5 scenario, using statistically downscaled MIROC6 data, predict a continued increase in short‐duration high‐magnitude rainfall events. To quantify flood inundation scenarios, this study developed a coupled hydrologic‐hydraulic (HH) model over a 35.5‐mile Mississippi River corridor. Simulations indicate that, without intervention, flood depths could rise by 20%–45% and the inundation extent of flooding could expand significantly in low‐lying areas of Rock Island and East Moline. To mitigate these risks, the study tested eight nature‐based solutions (NbS), including bioswales, rain gardens, riparian buffers, infiltration trenches, and detention basins. HH modeling showed that the combined implementation of NbS can reduce peak discharge by up to 69.4% and increase water infiltration by over 25%, resulting in an estimated 37% reduction in flooded areas by the end of the century. Through over 30 stakeholder interviews, three public forums, and participatory mapping workshops, residents identified priority flood zones and proposed NbS strategies. This integrated approach helped develop a streamlined framework that combines high‐resolution flood modeling with community‐led planning, creating robust and socially equitable adaptation pathways for riverine urban systems.
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- PAR ID:
- 10673327
- Publisher / Repository:
- AGU
- Date Published:
- Journal Name:
- Community Science
- Volume:
- 5
- Issue:
- 1
- ISSN:
- 2692-9430
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1029/2025CSJ000151
