Kalahari Desert, Namibia

abandoned aerial photography aerial africa arid august barren black desert desertification deserts drought dry dune dunes earth observation encroaching enhanced thematic mapper plus environment environmental etm etm+ farm farms from space geography geology infrared kalahari desert landsat 7 namibia namibian optical river rivers road sand dune sand sands sandy satellite image satellite photography satellite view satellite seven topographical topography use usgs visible white