Kalahari Desert, Southern Africa
Derived from a Tswana word meaning “waterless place,” the Kalahari Desert is a large stretch of semiarid, sandy savannah that covers part of Botswana, Namibia, and South Africa. The Kalahari has vast areas covered by red sand without any permanent surface water. The Kalahari is regarded as a semidesert because some portions support more vegetation from erratic rainfall, while other areas are truly arid. In this Landsat 7 image from 2000, the Nossob River cuts through colorful streaks of sand deposits. The red dot near the river in the center of this image represents a farm made possible by a center-pivot irrigation system.