Accurate land elevation data are crucial for coastal flood risk assessments. Previous data limitations led to high uncertainty in sea-level rise (SLR) projections. This study utilizes the first global elevation model derived from satellite LiDAR data, revealing that 62% (649,000 km²) of the globally vulnerable land area (less than 2 m above mean sea level) is located in the tropics. Even with a conservative 1-meter SLR by 2100 and stable lowland populations, the affected population (267 million in 2020) would increase to at least 410 million, with 72% residing in the tropics and 59% in tropical Asia.

A. Hooijer, R. Vernimmen