Rising seas could affect three times more people by 2050 than previously thought, according to new research, and could drown some of the world’s great coastal cities.
The study by the New Jersey based Climate Central, using improved elevation data, reveals that hundreds of millions more people than previously estimated live on land that is vulnerable to the impacts of sea level rise and coastal flooding, without new or augmented coastal defenses.
By 2050, rising seas could push annual floods above land that is now home to approximately 300 million people (vs. 79 million in assessments using prevailing elevation data).
By midcentury, high tide lines could permanently climb above land that is currently occupied by an estimated 150 million inhabitants (vs. 38 million).
By 2100, land that is now home to 360 million could fall below the annual flood risk line (vs. 100 million in assessments using prevailing elevation data).
Land home to 200 million (vs. 52 million) could fall beneath the permanent high tide line.
The annual flood risk line is the height of the average annual flood (higher than the high tide line).
Six Asian nations (China, Bangladesh, India, Vietnam, Indonesia, and Thailand) are home to the majority of people on land at risk.
Approximately 237 million people in these countries now occupy areas that, without sufficient levees or other defenses, could be threatened by coastal flooding one or more times per year by 2050, nearly quadrupling estimates based on older elevation data.
