The Full Wiki

Patagonian Desert: Wikis

Advertisements
  
  

Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.

Encyclopedia

From Wikipedia, the free encyclopedia

Patagonian by NASA World Wind
Astronaut photography of the Patagonian Desert (most of the view) contrasted with the Limay River, seen flowing eastward from the Andes.

The Patagonian Desert, also known as the Patagonia Desert or the Patagonian Steppe, is the largest desert in America and is the 7th largest desert in the world by area, occupying 260,000 square miles (673,000 km²). It is located primarily in Argentina with small parts in Chile and is bounded by the Andes, to its west, and the Atlantic Ocean to its east, in the region of Patagonia, southern Argentina.

Contents

Geography and climate

The Patagonian Desert is the largest continental landmass of the 40° parallel and is a large cold winter desert, where the temperature rarely exceeds 12°C and averages just 3°C. The region experiences about seven months of winter and five months of summer. Frost is not uncommon in the desert but, due to the very dry condition year round, snow is. The Andes, to the desert's west, are the primary reason for the Patagonian's desert status as they inhibit the westerly flow of moisture from the southern Pacific from reaching inland. This creates a rain shadow that accounts for the formation of the desert and is why, despite approximately half of the desert being only about 200 miles from the ocean, such a large desert is found in the region.[1] The cold Falkland Current off the Atlantic coast of South America also contributes to the area's aridity.

Small area of runoff at the Andes' end of the barren Patagonian Desert.

Before the Andes were formed, the region was likely covered by temperate forests. However, after the formation of the Andes, ash from nearby volcanoes covered the forests and mineral-saturated waters seeped into the logs, thus fossilizing the trees and creating one of the world's best preserved petrified forests in the desert's center.[2] The Patagonian is mainly composed of gravel plains and plateaus with sandstone canyons and clay shapes dotting the landscape, sculpted by the desert wind.[3] The region encompassing the desert, however, has many diverse features. Ephemeral rivers, lakes, and drainage deposits from the Andes' spring melt form annually, hosting a variety of waterfowl and aquatic grasses. A variety of glacial, fluvial, and volcanic deposits are also found in the region and have significantly affected the desert's climate over time, especially contributing to the gravel sediments covering parts of the Patagonian.

The desert is quite windy as well, a result of the rain shadow effect and descending cool mountain air. This wind helps make the Patagonian one of the largest, if not the largest, sources of dust over the South Atlantic Ocean.[4]

Fauna and Flora

Despite the harsh desert environment, a number of animals venture into and live in the Patagonian. Some only live on the more habitable and geographically-varied outskirts of the desert, where food is more abundant and the environment less hostile, but all are found within the region encompassing the Patagonian. The burrowing owl, lesser rhea, guanaco, tuco-tuco, mara, pygmy armadillo, Patagonian weasel, puma, Patagonian gray fox, desert iguana, Jumping Cow Spider, and various species of eagle and hawk are a few of the variety of animals living in the region.

The flora of the region is quite common for its climate and includes several species of desert shrubs like Acantholippia and Benthamiella and tuft grasses like Stipa and Poa. Aquatic grasses and larger flora exist on the outskirts of the desert and around the ephemeral lakes that form from the Andes' runoff.[5]

Human Influence

The desert has hosted various indigenous peoples in its past, as evidenced by cave paintings in the area. The area is sparsely populated today and those that do live here survive mainly by the raising of livestock such as sheep and goats. Resource mining, especially of oil, gas, and coal in parts of the region, is another way humans interact with and influence the desert environment. Poaching and hunting of some of the animals, like the various species of foxes, has further pressured the already fragile ecosystem.

See also

References


Patagonia

Cuernos del Paine from Lake Pehoé.jpg
Regions
Eastern Patagonia
Western Patagonia
Tierra del Fuego
Ecoregions
Valdivian forests
Magellanic forests
Patagonian steppe
National Parks
Nahuel Huapi
Torres del Paine
Cape Horn
Political divisions
Palena Province
Aisén Region
Magallanes Region
Neuquén Province
Río Negro Province
Chubut Province
Santa Cruz Province
Tierra del Fuego Province
  1. ^ McDonald, James E. Climatology of Arid Lands, Arid Lands Information Center, University of Arizona.
  2. ^ PBS. Central Steppes
  3. ^ BBC. Paian
  4. ^ Gasso, S.; Gaiero, D. M.; Villoslada, B.; Liske, E. Observations and Measurements of Dust Transport from the Patagonia Desert into the South Atlantic Ocean in 2004 and 2005. The Smithsonian/NASA Astrophysics Data System, Harvard University.
  5. ^ World Wildlife Fund. Patagonian Steppe
  • Gasso S. and Stein A.F., Does dust from Patagonia reach the sub-Antarctic Atlantic ocean? Geophys. Res. Letters, 34 (1): Art. No. L01801 JAN 3 2007.
  • Joseph R. McConnell, Alberto J. Aristarain, J. Ryan Banta, P. Ross Edwards, and Jefferson C. Simo, 20th-Century doubling in dust archived in an Antarctic Peninsula ice core parallels climate change and desertification in South America, Published online before print March 26, 2007, 10.1073/pnas.0607657104

Advertisements

Advertisements






Got something to say? Make a comment.
Your name
Your email address
Message