Expansion/Contraction of the Sahara from 1980 to 1997

Satellite data and ground rainfall measurements have been used to study variations in the size of the Sahara Desert from 1980 to 1997. Through a combination of the satellite and ground data, the 200 mm/yr precipitation boundary was mapped for the Saharan-Sahelian region by year. Although highly significant year-to-year variation in the size of the Sahara Desert has occurred, no systematically increasing or decreasing trend from 1980 to 1997 was evident. The area of the Sahara Desert varied from 9,980,000 sq km in 1984 to 8,600,000 sq km in 1994 and had an average area of 9,150,000 sq km from 1980 to 1997.