Where is the driest desert?

Atacama desert
   The 600-mile-long Atacama Desert in the northern tip of Chile, running from Arica (elevation 95 feet) on the Pacific Ocean to Antofagasta (elevation 3,380 feet) at the base of the Andes Mountains, is a virtually rainless plateau. With prevailing easterly winds, all moisture that accumulates is dropped on the eastern side of the Andes, in the Amazon rain forest. The desert on the west side of the Andes averages .004 inch of annual rainfall; Arica averages .03 inch. In spite of the lack of rain, plants, ani­mals, and even a few people are able to survive here because of the fog and dew that blow in from the Pacific Ocean, a series of salt lakes in the mountains, and underground water.
   Wadi Halfa in the Sudan and Death Valley in California each have .1 inch of annual rainfall.