Abstract
Sea level rise, coastal erosion and climate change are major stressors for coastal communities, whose expansion may be also limited by land scarcity and environmental issues. Floating cities may represent an interesting solution, but require further conceptual development, both in terms of technological means and architectural vision. Furthermore, their feasibility and sustainability still need to be explored more in depth. In view of these gaps, here we propose an innovative floating city vision, based on a comprehensive approach, including qualitative and quantitative analyses and ranging between all the above-mentioned topics. The concept is built around three pillars: resilience, sustainability, and urban welfare, corresponding to the three elements of water, nature, and man, respectively. A preliminary quantitative analysis about space, food and energy requirements confirms the feasibility of the floating city and provides a benchmark for future investigation on similar concepts.
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Data availability
The energy consumption data reported in Supplementary Table 2 are obtained from the freely accessible online IEA data services (license: CC BY 4.0, website: https://www.iea.org/countries).
The population data reported in Supplementary Table 2 are obtained from the freely accessible online World Bank Open Data (license: CC BY 4.0, website: https://data.worldbank.org/indicator/).
The annual solar energy production data in the three sample sites (North Sea, Aegean Sea, Hong Kong) are generated using the freely accessible online PVGIS tool v5.3, provided by the European Commission (license: CC BY 4.0, website: https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html).
The wind Weibull parameter data in two out of the three sample sites (North Sea, Aegean Sea) are obtained from the New European Wind Atlas, a free, web-based application developed, owned and operated by the NEWA Consortium (license: CC BY 4.0, website: https://map.neweuropeanwindatlas.eu/).
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Acknowledgements
This work was partially funded by the Next Generation EU—Italian NRRP, Mission 4, Component 2, Investment 1.5, call for the creation and strengthening of ‘Innovation Ecosystems’, building ‘Territorial R&D Leaders’ (Directorial Decree n. 2021/3277)—project Tech4You—Technologies for Climate Change Adaptation and Quality of Life Improvement, n. ECS0000009. This work reflects only the authors’ views and opinions; neither the Ministry for University and Research nor the European Commission can be considered responsible for them. Second author’s work was funded by a scholarship entitled “Offshore plants for the conversion of sea wave energy into electricity” in the context of the Collaboration Agreement CARMA Società Agricola A.R.L. ARTISTSXCARMAXCLIMATECHANG, charity initiative proposed by the artist Norma Jeane, to whom the author is very grateful.
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F.A. led the paper conceptualization, methodology, funding acquisition and supervision. C.R. led the multi-disciplinary analyses of the floating city, including barrier characterization and energy consumption and production quantification. M.L.C led the architectural conceptualization, the masterplan and the graphical project, with contributions and coordination from C.R. C.R. led the resilience, urban welfare, sustainability, and cost assessment frameworks, with contributions from M.L.C. C.R. led the writing. M.L.C. and F.A. contributed to the review and editing.
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Ruzzo, C., Cacurri, M.L. & Arena, F. Rethinking and comprehensive planning of the floating city concept. Commun Earth Environ (2026). https://doi.org/10.1038/s43247-026-03218-3
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DOI: https://doi.org/10.1038/s43247-026-03218-3
