Atacama Desert Atacama Desert The Atacama Desert () is a desert plateau in South America covering a 1000-km (600-mi) strip of land on the Pacific coast, west of the Andes mountains. The Atacama desert is one of the driest places in the world (the driest being the McMurdo Dry Valleys ) , as well as the only true desert to receive less precipitation than the polar deserts. According to estimates, the Atacama Desert occupies , or if the barren lower slopes of the Andes are included. Most of the desert is composed of stony terrain, salt lakes ("salares"), sand, and felsic lava
Flora of the Sonoran Desert absent on the California side of the Colorado River. Desert Holly ("Atriplex hymenelytra") can tolerate even the hottest and driest sites. The area where two vegetation types border, overlap, and transition is called an ecotone. The ecotone between the hotter, drier Colorado Desert and that of the relatively cooler and wetter Arizona Upland occurs from Parker, Arizona southeast to near Phoenix, then south to Organ Pipe Cactus National Monument. Density of vegetation gradually diminishes moving from the Arizona Upland into the Colorado Desert proper. can be found with stems climbing through shrubs and other vegetation, producing "spectacular" floral displays on