This photo, taken from space, shows the Southeast Pacific Ocean on the left, with patches of stratocumulus clouds along the coast of South American. Moving to the right (east) one can see the low lying coastal Atacama Desert and the Andes Mountain Range.
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Image Courtesy of NASA

The Andes Mountains

The Andes Mountains form one of the longest mountain ranges on Earth, stretching over 7,000 km (4,400 miles) along the west coast of South America. The Andes are very narrow in most places and the average width of the Andes is 200 km (124 miles). The height of the Andes is about 4,000 meters (13,123 feet) high, and it includes peaks above 6,000 meters (19,685 feet). Aconcagua, the highest peak in the Andes, is 6,962 meters (22,841 feet). Many of the peaks in the Andes are active volcanoes. The mountain range is part of seven countries: Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, and Venezuela .

The Andes are a massive barrier between the eastern Pacific Ocean and the rest of the continent of South America. This barrier impacts the climate of South America. The northern part of the Andes is typically rainy and warm. The west side of the central Andes is extremely dry and includes the Atacama Desert in northern Chile; the eastern portion of the central Andes is much wetter. In the south, the western side of the Andes tends to be wet, while the eastern plains of Argentina are in a rain shadow and tend to be very dry. Many of the peaks in the Andes receive heavy snowfall and contain glaciers.

The forces of plate tectonics are responsible for the formation of the Andes. The Nazca plate and a part of the Antarctic plate have been subducting beneath the South American plate, which is a process that continues today and causes earthquakes and volcanic eruptions in the region.

The Inca Empire started in the mountains of Peru in the early 13th century and spread throughout the Andes in the 1400s. The Incas built roads and aqueducts throughout the mountain range. Inca engineers constructed impressive sites, including the capital city of Cuzco and Machu Picchu. In the 1530s a civil war and exposure to European diseases destroyed most of the Inca Empire.

Last modified November 17, 2008 by Julia Genyuk.

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