The Aral Sea in 1989 (left), and now (2014) Once the fourth-biggest lake in the world, the eastern basin of the Aral Sea in central Asia is now completely dry. It is the result of a Soviet-era project to divert rivers for agriculture and a lack of rainfall at its source. “This is the first time the eastern basin has completely dried in modern times,” Philip Micklin, an Aral Sea expert from Western...