The drying up of the Aral Sea has made Central Asia 7% dustier in the last 30 years. Between 1984 and 2015, dust emissions from the growing desert almost doubled from 14 to 27 million tons.

When Alexander the Great conquered this territory in the fourth century B.C., these rivers already had a long history of providing lifeblood to Central Asia. For centuries the Aral Sea and its ...