Elusive, but ecologically vital, Namibia's Ugab River only flows above ground
for a few days each year. The subterranean waters underlying this ephemeral
river, however, are shallow enough in places to fill hollows and sustain a
wildlife population that includes the rare desert elephant.
This image was acquired by Landsat 7’s
Enhanced Thematic Mapper plus (ETM+) sensor.
Image provided by the
USGS EROS Data Center Satellite Systems
Branch as part of the Earth as Art II image series