The annual average rainfall in northern Chile is 1 millimeter or 0.04 inch. Northern Chile is home to the Atacama Desert, which is the most arid place in the world.
The northern part of Chile receives very little precipitation due to the Humboldt current and the Pacific anticyclone. The desert lacks moisture, so is unable to sustain plant life. The mountains over 20,000 feet above sea level do not form glaciers, while some river beds have been parched for thousands of years. Certain organisms, such as algae and cacti, are able to thrive in northern Chile from the moisture provided by a fog known as "Camanchaca."