TOKYO -- As sea levels continue to rise because of global warming, "zero-meter zones" -- a term for areas below sea level -- are growing. Many of the world's major cities are located on coastal flatlands, and a growing number of people are at risk of inundation from rising seas. Looking ahead over the next 100 years, procedures to protect cities and their residents will undoubtedly be tested.
Infographic: 'Zero-meter zones' expand globally as sea levels rise
Millions of city dwellers worldwide face mounting inundation threat