Erosion reduces crop yields and causes problems for hundreds of millions of people.

Su Rongxi next to his house in Hebei province, China, after dust storms nearly buried it. "We have no money to move and, besides, who would have us?" says Su. "There's nothing to do but dig away the sand and wait to see what happens. Sometimes I dream of the sand falling around me faster than I can dig away. The sand chokes me. I worry that in real life, the sand will win."