South America Physical Geography Summary

South America: Physical Geography

Introduction

  • 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.

Mountains

  • 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.

Highlands

  • Plateau: An area of relatively level high ground.
  • Two famous plateaus: Altiplano (Peru and Bolivia) and Patagonia (Argentina and Chile).
  • Altiplano elevation: 3,7003,700 meters (12,30012,300 feet).
  • Patagonia elevation: 1,2001,200 meters (3,9303,930 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.

River Basins

  • Three important river basins: Amazon, Orinoco, and Paraguay/Paraná.
  • Amazon River basin size: 77 million square kilometers (2.72.7 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 2,7362,736 kilometers, covering an area of about 948,000948,000 square kilometers, encompassing approximately 8080% of Venezuela and 2525% 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 2.82.8 million square kilometers (1,081,0001,081,000 square miles).
  • Paraná River includes Iguazu Falls, extending for 2.72.7 kilometers (1.71.7 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.

Coastal Plains

  • 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 11 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.