The Aral Sea used to be the fourth-largest inland sea on Earth, acting as an influencing factor in the air moisture and arid land use. Since the 1960s, the decade 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. Reliable, or even approximate data, have not been collected, stored or provided by any organisation or official agency. 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.