The Aral Sea was once the fourth-largest inland sea on Earth, humidifying the surrounding air and irrigating the arid land. Since the 1960s, when the overuse of the Aral Sea water began, it has shrunk to about 10% of its former area and divided into parts, with only the southern part of the narrow western lobe of the South Aral Sea remaining permanently in Uzbekistan. Much of the water was and continues to be used for the irrigation of cotton fields, a crop requiring a large amount of water to grow.