South America Physical Geography Summary

South America is a continent of extremes, extending from the Gulf of Darien to the Archipelago of Tierra del Fuego.
It is the fourth largest continent.
Three physical regions: Mountains and Highlands, River Basins, and Coastal Plains.
Mountains and Coastal Plains run north-south, while Highlands and River Basins run east-west.
Diverse biomes due to extreme geographic variation: very dry deserts, tropical rainforests, river basins, and vast grasslands.

Primary mountain system: Andes, the world's largest.
The Andes is approximately 8,850 kilometers long.
Located along the western coast of South America, from the southern tip to the northernmost coast.
Many peaks exceed 4,500 meters in height.
Highest peak: Mount Aconcagua, 22,831 feet tall, located in the Southern Andes.

Plateau: An area of relatively level high ground.
Two famous plateaus: Altiplano (Peru and Bolivia) and Patagonia (Argentina and Chile).
Altiplano elevation: $3,700$ meters ( $12,300$ feet).
Patagonia elevation: $1,200$ meters ( $3,930$ feet).
Alpine biome plants: small, stiff, and strong.
Largest herb in the world: Puya Raimondii (Queen of the Andes), lifespan of 100 years, size of 9 meters.

Three important river basins: Amazon, Orinoco, and Paraguay/Paraná.
Amazon River basin size: $7$ million square kilometers ( $2.7$ million square miles), the largest watershed in the world.
The Amazon covers most of northern South America, fed by tributaries from the Andes glaciers.
The Amazon River is the life force of the Amazon rainforest, making up about half of the planet's rainforests.
Rainforest biome: swamp grasses, sedges, and bunchgrass, ideal for diverse animal species like bird species, piranhas, electric eels, and the Orinoco crocodile.
Rainforests contain more than 2 million insect species and hundreds of spider and butterfly species.
Orinoco River: flows over $2,736$ kilometers, covering an area of about $948,000$ square kilometers, encompassing approximately $80$ % of Venezuela and $25$ % of Colombia.
Primary biome of the Orinoco River basin: Llanos (savanna or grassland).
The Llanos biome features various grasses and provides habitat for bird species, piranhas, and eels.
Paraguay/Paraná River basin covers almost $2.8$ million square kilometers ( $1,081,000$ square miles).
Paraná River includes Iguazu Falls, extending for $2.7$ kilometers ( $1.7$ miles).
The Paraná River empties into the Rio de la Plata estuary, between Argentina and Uruguay.
The Amazon, Orinoco, and Paraguay/Paraná regions are important due to fertile land, benefiting farmers economically.

A coastal plain is an area of low, flat land next to a seacoast.
South American coastal plains are found on the northeastern coast of Brazil (Atlantic Ocean) and the western, Pacific coast of Peru and Chile.
The coastal plains of northeastern Brazil and the western coastal plains are extremely dry.
Thermal inversion: cold air at sea level and stable, warmer air higher up, produces a thick layer of clouds at low altitudes, preventing precipitation.
The Atacama Desert is located in the western coastal plain.
The Atacama Desert is the driest region globally, with very few plants, larger animal species, and an average rainfall of 1 millimeter (0.04 inches) a year.
Atacama Desert biome features an average rainfall of $1$ mm per year and is home to species like the grey fox, Huemul, Viscacha, penguins, cormorants, and pelicans and serves as a rich source of copper, and it's a chief source of revenue for the Chilean economy.