South America is home to a number of extensive, extremely arid and visually stunning deserts. From the Atacama Desert in Chile, which is the driest desert in the world, to the iconic sand dunes of the miniature Medanos de Coro Desert in Venezuela, to the vast and cold Patagonian Desert in Argentina --- South America is home to some of the most inhospitable and beautiful environments on the planet.
The Atacama Desert, located in Northern Chile and extending from the Pacific Coast right up into the Andean Cordillera, is certainly the driest desert in the world, and it may also be the oldest. Up in the mountains, the desert sees as little as 0.004 inches of rain a year, and it has been estimated that some parts of the Atacama have not seen rain for more than 400 years. The Atacama is considered by many experts to be the oldest desert in the world, with estimates of its age ranging from 5 million to 20 million years. Despite its extreme aridity, the Atacama is not a particularly hot desert, ranging between 0 and 25 degrees Celsius. Due to its low rainfall, it is almost devoid of any vegetation and endemic animal species, the exception being some species of cyanobacteria found under rocks and in caves, which are moisturized by water vapor traveling inland from the sea.
The Patagonian Desert is located in southern Argentina and across the border into Chile. It is a cold desert, experiencing snow in the winter, and also very arid. Winter lasts for five months, between June and September, and temperatures can drop as low as three degrees Celsius below zero. The desert is home to a small human population and a fragile ecosystem of plants and animals. Indigenous red foxes and pumas have been hunted and poisoned nearly to extinction.
The Sechura Desert is largest desert located on the Pacific Coast of South America, extending 2,000 km and occupying in excess of 188,000 square kilometers. It is extremely dry and possesses an average annual temperature of 22 degrees Celsius. Most of the region is of recent origin, but it is interspersed with marine outcrops that extend as far back as the Cretaceous Period, some 140 million years ago. The desert is home to a number of endemic plant species, which make up the distinct lomas vegetation. The arid region is also an important migration corridor for birds, such as the Arctic sanderling and Baird's sandpiper. The desert is also home to a variety of desert lizards. Unlike other desert regions in South America, the Sechura has a relatively high human population, which poses an ongoing threat to the desert's fragile ecosystem.
Los Medanos de Coro desert in Venezuela's northwestern Falcon State is quite possibly the smallest desert in South America. Measuring 30 kilometers by 5 kilometers, the desert is constantly exposed to the trade winds that blow over the Paraguana Peninsula, which was once an island but which is now connected to the mainland by an isthmus. Coro translates as "wind" in the indigenous Arawak dialect.
