Global sea level could rise 50 feet by 2300

Global average sea-level could rise by nearly eight feet by 2100 and 50 feet by 2300 if greenhouse gas emissions remain high, posing a major risk to coastal populations and ecosystems around the world, according to a study. Since the start of the century, global average sea-level has risen by about 0.2 feet, said researchers at the Rutgers University in the US.

Under moderate emissions, central estimates of global average sea-level from different analyses range from 1.4 to 2.8 more feet by 2100, 2.8 to 5.4 more feet by 2150 and 6 to 14 feet by 2300. With 11 per cent of the world’s 7.6 billion people living in areas less than 33 feet above sea level, rising seas pose a major risk to coastal populations, economies, infrastructure and ecosystems around the world, the researchers said.

Sea-level rise varies over location and time, and scientists have developed a range of methods to reconstruct past changes and project future ones. However, despite the differing approaches, a clear story is emerging regarding the coming decades, researchers said. From 2000 to 2050, global average sealevel will most likely rise about 6 to 10 inches, but is extremely unlikely to rise by more than 18 inches, they said.

Beyond 2050, projections are more sensitive to changes in greenhouse gas emissions and to the approaches for projecting sea-level change.