Rising Seas, Rising Risks: Buildings in the Global South Face Centuries of Inundation

Brown Booby

18-09-2025

After checking and comparing the data, all the inspectors found clearly that Mr. Sparrow’s family was the only one violating the permitted threshold and must change their environmentally destructive behaviors. Although the whole Sparrows family ate and pooped very little, all the maths “suggest” that the amount of feces in the Sparrows family is very high.

In “GHG Emissions”; Wild Wise Weird [1]

© Olesya Stepanova

Sea level rise (SLR) is one of the most far-reaching consequences of climate change, threatening coastlines, infrastructure, and livelihoods worldwide. Nearly 30% of the global population lives within 50 km of the coast, and 20 of the world’s 26 largest megacities are coastal [2,3]. While people may relocate, buildings and infrastructure cannot. A new study by Willard-Stepan and colleagues [4] provides the first large-scale, building-by-building assessment of exposure to long-term sea level rise across the Global South.

Using high-resolution satellite data and digital elevation models, the researchers mapped 840 million buildings in Africa, Southeast Asia, and Latin and Central America. They found that 3 million buildings would be inundated under 0.5 m of local sea level rise (LSLR)—the lower bound of projections by 2100 even under low-emissions pathways. This number soars to 45 million at 5 m and 136 million at 20 m, levels that may be reached in the coming centuries depending on emissions and ice-sheet dynamics [4].

The risks are unevenly distributed. At early stages of sea level rise, Africa faces the highest exposure, but as seas climb beyond 2–4 m, Southeast Asia rapidly dominates losses. Vulnerability is particularly acute in estuaries and deltas such as the Nile, Amazon, and Mekong, where dense urban settlements meet low-lying terrain. Some countries could lose more than 80% of their building stock under high-end scenarios.

These findings underscore the stark differences between low- and high-emissions futures. Limiting warming under the Paris Agreement would still threaten millions of buildings by 2300, but unchecked emissions could lock in catastrophic losses. While flood defenses and land reclamation may help in some places, their costs and feasibility diminish as seas continue to rise [5,6].

Human emissions drive ice melt and rising seas, which in turn reshape human settlements. Every ton of carbon avoided is not only an investment in climate stability but also a safeguard for the homes, cultures, and economies of future generations [7]. This underscores the need to cultivate Nature Quotient (NQ) within society—the capacity to recognize and act on ecological interdependence. Strengthening NQ means acknowledging that protecting coastal communities is inseparable from reducing emissions and integrating ecosystem safeguards into planning and governance [8]. 

References

[1] Vuong QH. (2024). Wild Wise Weird. https://books.google.com/books?id=N10jEQAAQBAJ

[2] Cosby AG, et al. (2024). Accelerating growth of human coastal populations at the global and continent levels: 2000–2018. Scientific Reports,14, 22489. https://doi.org/10.1038/s41598-024-73287-x 

[3] World Ocean Forum. (2017). Megacities by the sea. https://medium.com/world-ocean-forum/megacities-by-the-sea-543c591de77c 

[4] Willard-Stepan M, et al. (2025). Assessing the exposure of buildings to long-term sea level rise across the Global South. npj Urban Sustainability, 5, 72. https://doi.org/10.1038/s42949-025-00259-z 

[5] Hinkel J, et al. (2014). Coastal flood damage and adaptation costs under 21st century sea-level rise. PNAS, 111, 3292-3297. https://doi.org/10.1073/pnas.1222469111 

[6] Siders AR, Hino M, Mach KJ. (2019). The case for strategic and managed climate retreat. Science, 365, 761-763 (2019). https://doi.org/10.1126/science.aax8346 

[7] Nguyen MH. (2024). How can satirical fables offer us a vision for sustainability? Visions for Sustainability, 23(11267), 323-328. https://doi.org/10.13135/2384-8677/11267 

[8] Vuong QH, Nguyen MH. (2025). On Nature Quotient. Pacific Conservation Biology, 31, PC25028. https://doi.org/10.1071/PC25028