Imagine stepping outside your home and finding it submerged in water; this could be the future for over 100 million buildings across the Global South. A stunning new study led by McGill University reveals that, without immediate action to curb fossil fuel emissions, rising sea levels could wreak havoc on coastal communities for centuries to come.

This groundbreaking research marks the first extensive assessment of the long-term effects of sea level rise on infrastructure in vulnerable regions like Africa, Southeast Asia, and Central and South America. The team utilized detailed satellite imagery and elevation data to meticulously map out how many buildings might be at risk under various sea level rise scenarios over the next several hundred years.

“Sea level rise is a slow, but unstoppable consequence of warming that is already impacting coastal populations and will continue for centuries,” warns Prof. Natalya Gomez, a lead author and Canada Research Chair at McGill. Her words carry weight, as she highlights that while many talk of sea levels rising by mere centimeters, the reality could be far graver: a rise of multiple meters if we don’t act swiftly against fossil fuel emissions.

Even a modest increase of just 0.5 meters — a level we could reach even with determined emission cuts — could inundate around three million buildings. But the stakes escalate dramatically: a rise of five meters or more, predicted if emissions remain unchecked, threatens over 100 million structures. This isn’t just about numbers; it’s about entire neighborhoods disappearing, critical infrastructure like ports and refineries being submerged, and cultural heritage sites being lost to the sea.

“We were taken aback by the sheer number of buildings at risk from what we consider 'moderate' long-term sea level rises,” shared Prof. Jeff Cardile, co-author of the study. The exposure varies greatly based on coastal topography, showcasing that some nations are far more vulnerable than others.

These findings are not merely academic; they provide essential insights for urban planners, policymakers, and communities as they strategize for the inevitable rise. Eric Galbraith, another professor on the team, emphasizes the universal impact of climate change: “Every one of us will be affected, whether we live by the coast or not.” The disruption of essential infrastructure, particularly in ports, could send shockwaves through our globally interconnected economy and food supply.

Fortunately, the researchers have made their study’s interactive map accessible through Google Earth Engine, allowing decision-makers to visualize which areas face the greatest threats and plan accordingly. This data is vital for developing climate adaptation strategies, from building protective structures to reassessing land use planning.

“There’s no escaping at least a moderate level of sea level rise,” cautions lead author Maya Willard-Stepan. “The sooner we start planning, the better we can ensure our communities continue to thrive.” This is a wake-up call for all of us; the time to act is now.

In summary, this transformative study by McGill University underscores the urgent need for climate action to protect vulnerable communities from the impending threat of sea level rise, as a staggering number of buildings are at risk of flooding.