Scientists are sounding the alarm that rising sea levels driven by climate change could displace tens of millions of people globally, sparking catastrophic inland migration and reshaping national demographics. According to recent projections published in Nature Climate Change, sea level rise could submerge key coastal cities by the end of the century—including parts of Mumbai, New York, Jakarta, Lagos, and Dhaka—threatening the homes of more than 410 million people by 2100 if greenhouse gas emissions remain unchecked. The majority of this displacement will occur within national borders, overwhelming urban infrastructure, housing, and job markets in inland areas already under strain.
The research highlights that vulnerable populations—especially in South Asia, sub-Saharan Africa, and small island states—face the highest risks due to rapid urbanization, poor adaptation planning, and existing socio-economic inequalities. For example, in India alone, over 36 million people could be forced to relocate from coastal regions, creating a migration crisis not unlike those caused by armed conflict or economic collapse. The scientists urge governments to integrate sea level projections into national planning strategies, calling for climate-adaptive infrastructure, managed retreat policies, and legal protections for internally displaced persons as critical components of climate resilience. More