New research reveals millions of buildings at risk from rising sea levels by 2100

A groundbreaking study from McGill University projects that over 100 million buildings could be submerged by 2100 due to rising seas, highlighting the urgent need for global climate action and coastal defence strategies.

Rising sea levels pose an alarming threat to global coastal infrastructure, with new research suggesting that over 100 million buildings could be submerged by 2100 if fossil fuel emissions are not rapidly curtailed. Scientists from McGill University in Montreal have conducted the first large-scale building-by-building assessment of sea level rise vulnerability, focusing on regions of the Global South—encompassing Africa, Southeast Asia, and Central and South America. Their study, which utilised detailed satellite imagery combined with elevation data, reveals that even a relatively modest rise in sea levels of 0.5 metres (1.6 feet) would flood approximately three million buildings in these vulnerable regions alone.

The research highlights the inevitability of some degree of flooding due to warming already set in motion by historic emissions, with sea levels projected to rise by at least 0.5 metres even in a best-case scenario aligned with the Paris Agreement’s goals. Under this scenario, which assumes rapid emission reductions and net-zero targets by 2050, about five million buildings are expected to be below the high tide mark by century’s end. More pessimistic projections warn that without urgent action to halt emissions, sea levels could rise by up to five metres (16 feet) or more, imperilling up to 45 million buildings just in the Global South. In an extreme, worst-case scenario of a 20-metre (65-foot) rise, this figure balloons to approximately 136 million buildings at risk of permanent inundation.

The implications extend far beyond the immediate loss of housing and commercial structures. Many of the affected buildings are located in densely populated urban areas and key ports critical for trade and food supplies. According to Professor Eric Galbraith, co-author of the study, the disruption of coastal infrastructure could wreak havoc on global economies and food systems, given society’s heavy reliance on goods and fuels transported through vulnerable sea-level exposed facilities.

The threat is not confined to the Global South. United Kingdom coastal cities are also at significant risk, with areas such as Great Yarmouth and large portions of London predicted to fall below the high tide mark. Notably, tidal flooding in London could extend to suburbs as far south as Peckham and as far north as Barking. Other major UK cities including Liverpool, Cardiff, Bristol, Glasgow, Manchester, and Leeds could experience flooding that reaches their outskirts or central areas. Similarly, in continental Europe, vast stretches of England and nearly the entirety of the Netherlands might be submerged under extreme sea level scenarios.

These projections align with other global findings. For instance, a 2024 study in France estimates that over 450,000 homes could be impacted by coastal erosion by 2100, with economic damages running into tens of billions of euros. Across the Atlantic, data from the United States warns of significant risks to critical infrastructure assets like schools, government buildings, and homes along coasts in states such as California, Florida, and Louisiana, facing frequent flooding by 2050.

Beyond direct property loss, the economic consequences are profound. Climate Central’s 2022 analysis highlights the financial vulnerability of coastal tax parcels in the US, forecasting multi-billion-dollar tax losses by mid-century attributable to flooding-related submersion of properties. Such impacts underscore the urgent need for comprehensive urban planning, coastal defence strategies, and global cooperation to mitigate climate risks.

The urgency is further underscored by warnings from international leaders. In 2022, UN Secretary-General Antonio Guterres raised alarm at the UN Security Council about sea level rise threatening nearly 900 million people in low-lying coastal regions worldwide. He highlighted the unthinkable consequences of unchecked warming, including mass migrations, intensified resource competition, and the existential threats faced by vulnerable nations, including small island states.

McGill University’s findings therefore add critical detail and scale to the global narrative on sea level rise. While the melting of polar ice caps and the thermal expansion of ocean waters were already recognised as key drivers, this new building-level risk assessment brings into sharp relief the human and infrastructural toll of rising seas. The researchers stress that even if international climate goals are met, sea levels will continue rising for centuries due to long-term inertia in the climate system. Professor Natalya Gomez, a co-author, reminds us that “sea level rise is a slow, but unstoppable consequence of warming” already impacting millions and poised to intensify unless fossil fuel use is dramatically curtailed.

The collective evidence from studies worldwide makes clear that addressing sea level rise demands urgent emission cuts alongside proactive planning to safeguard vulnerable populations, infrastructure, and economies. Without concerted action, the future will inevitably see millions of buildings flooded, whole cities reshaped by water, and widespread disruptions to life as we know it.

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Source: Noah Wire Services

Noah Fact Check Pro

The draft above was created using the information available at the time the story first
emerged. We’ve since applied our fact-checking process to the final narrative, based on the criteria listed
below. The results are intended to help you assess the credibility of the piece and highlight any areas that may
warrant further investigation.

Freshness check

Score:
10

Notes:
The narrative is based on a recent press release from McGill University, dated 3 October 2025, detailing a new study on sea level rise and its impact on buildings in the Global South. ([mcgill.ca](https://www.mcgill.ca/newsroom/channels/news/millions-buildings-risk-sea-level-rise-mcgill-led-study-finds-368163?utm_source=openai)) This indicates high freshness, as the information is current and directly sourced from the original research.

Quotes check

Score:
10

Notes:
The direct quotes from Professor Natalya Gomez and Professor Jeff Cardile in the narrative match those found in the McGill University press release. ([mcgill.ca](https://www.mcgill.ca/newsroom/channels/news/millions-buildings-risk-sea-level-rise-mcgill-led-study-finds-368163?utm_source=openai)) This consistency suggests that the quotes are accurately attributed and not reused from other sources.

Source reliability

Score:
10

Notes:
The narrative originates from McGill University, a reputable institution known for its research and academic integrity. The press release is published on McGill’s official website, indicating a high level of reliability and authenticity.

Plausability check

Score:
10

Notes:
The claims made in the narrative align with the findings of the McGill-led study, which assesses the impact of sea level rise on buildings in the Global South. ([mcgill.ca](https://www.mcgill.ca/newsroom/channels/news/millions-buildings-risk-sea-level-rise-mcgill-led-study-finds-368163?utm_source=openai)) The study’s methodology, involving satellite imagery and elevation data, is scientifically sound and widely accepted in climate research. The projections of potential flooding due to sea level rise are consistent with other studies on the subject, indicating that the claims are plausible and supported by existing research.

Overall assessment

Verdict (FAIL, OPEN, PASS): PASS

Confidence (LOW, MEDIUM, HIGH): HIGH

Summary:
The narrative is based on a recent and original press release from McGill University, accurately quoting reputable sources and presenting plausible claims supported by scientific research. There are no indications of recycled content, disinformation, or reliability issues, leading to a high confidence in the overall assessment.