Sea level rise is already affecting millions—and as oceans continue to rise due to climate change, the threat will expand dramatically. But not all regions are equally vulnerable. The greatest risk is to low-elevation coastal zones, many of which are densely populated, economically vital, and poorly equipped to adapt.
Elevation is one of the most important factors in assessing sea level rise vulnerability. Most risk assessments focus on land that lies at or below 10 meters (about 33 feet) above current sea level. But even 1–2 meters (3–6 feet) of sea level rise can lead to frequent flooding, saltwater intrusion, and eventual permanent inundation.
The Intergovernmental Panel on Climate Change (IPCC) warns that under high-emissions scenarios, global sea levels could rise 0.6 to 1.1 meters by 2100, and several meters more over the coming centuries.
Key Regions at Risk
Southeast Asia: Countries like Vietnam, Bangladesh, Thailand, and the Philippines are among the most exposed. The Mekong Delta in Vietnam, for instance, has vast farmland and cities sitting just 1–2 meters above sea level.
South Asia: Bangladesh is famously vulnerable. With over 19 million people living below the 1-meter elevation mark, even small rises could displace millions.
Small Island Nations: Low-lying countries such as the Maldives, Tuvalu, Kiribati, and the Marshall Islands sit just 1–3 meters above sea level, making them existentially threatened by any meaningful sea rise.
U.S. Gulf and East Coasts: States like Florida, Louisiana, and North Carolina face extreme risk. Miami, New Orleans, and Charleston already experience sunny-day flooding due to high tides, and large areas of Florida lie under 2 meters elevation.
Africa: Major cities like Alexandria (Egypt), Lagos (Nigeria), and parts of Mozambique are all within the low-elevation coastal zone, putting millions at risk.
Europe: The Netherlands, despite its advanced flood defenses, has roughly 26% of its land below sea level. Cities like Venice are also highly vulnerable.
What Elevations Are Most Critical?
- 0–1 meter: Immediate risk of submersion in many regions
- 1–2 meters: Major flood and saltwater intrusion risk
- Up to 10 meters: Still considered high-risk due to storm surges, extreme tides, and long-term sea level rise
A 2019 Nature Communications study found that up to 300 million people currently live on land that will be below annual flood levels by 2050.
Sea level rise isn’t just a future problem—it’s reshaping coastlines today. Populations under 10 meters elevation, especially in poor and densely populated regions, will bear the brunt. As ice melt accelerates, understanding elevation risk is key to planning for climate adaptation, migration, and infrastructure resilience.
Explore your area’s sea level risk with tools like Climate Central’s Coastal Risk Map.